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Suspect myopathy? Take this approach to the work-up
› Categorize patients with muscle complaints into suspected myositic, intrinsic, or toxic myopathy to help guide subsequent work-up. C
› Look for diffusely painful, swollen, or boggy-feeling muscles—as well as weakness and pain with exertion—in patients you suspect may have viral myopathy. C
› Consider electromyography and muscle biopsy for patients you suspect may have dermatomyositis. C
Strength of recommendation (SOR)
A Good-quality patient-oriented evidence
B Inconsistent or limited-quality patient-oriented evidence
C Consensus, usual practice, opinion, disease-oriented evidence, case series
CASE › Marie C, a 75-year-old Asian woman, reports weakness in her legs and arms with unsteadiness when walking. She has a vague but persistent ache in her large muscles. Her symptoms have developed slowly over the past 3 months. She denies recent signs or symptoms of infection or other illness. Her medical history includes hypertension, hyperlipidemia, osteopenia, and obesity. Ms. C takes lisinopril 10 mg/d and atorvastatin, which was recently increased from 10 to 20 mg/d.
What would your next steps be in caring for this patient?
Patients who experience muscle-related symptoms such as pain, fatigue, or weakness often seek help from their family physician (FP). The list of possible causes of these complaints can be lengthy and vary greatly, from nonmyopathic conditions such as fibromyalgia to worrisome forms of myopathy such as inclusion body myositis or polymyositis. This article will help you to quickly identify which patients with muscle-related complaints should be evaluated for myopathy and what your work-up should include.
Myopathy or not?
Distinguishing between myopathy and nonmyopathic muscle pain or weakness is the first step in evaluating patients with muscle-related complaints. Many conditions share muscle-related symptoms, but actual muscle damage is not always present (eg, fibromyalgia, chronic pain, and chronic fatigue syndromes).1 While there is some overlap in presentation between patients with myopathy and nonmyopathic conditions, there are important differences in symptoms, physical exam findings, and lab test results (TABLE 11-4). Notably, in myopathic disease, patients’ symptoms are usually progressive, vital signs are abnormal, and weakness is common, whereas patients with nonmyopathic disease typically have remitting and relapsing symptoms, normal vital signs, and no weakness.
Myopathy itself is divided into 3 categories—myositic, intrinsic, and toxic—which reflect the condition, or medication, that brought on the muscle damage (TABLE 22,4-15). Placing patients into one of these categories based on their risk factors, history, and physical exam findings can help to focus the diagnostic work-up on areas most likely to provide useful information.
Myositic myopathy can be caused by infection or autoimmunity
Myositic myopathies result in inflammatory destruction of muscle tissue. Patients with myositic myopathy often exhibit fever, malaise, weight loss, and general fatigue. Though weakness and pain are common, both can be variable or even absent in myositic myopathy.2,5 Myositic myopathy can be caused by infectious agents or can develop from an autoimmune disease.
Infectious myositic myopathy is one of the more common types of myopathy that FPs will encounter.2 Viruses such as influenza, parainfluenza, coxsackievirus, human immunodeficiency virus, cytomegalovirus, echovirus, adenovirus, Epstein-Barr, and hepatitis C are common causes.2,4,16 Bacterial and fungal myositides are relatively rare. Both most often occur as the result of penetrating trauma or immunocompromise, and are generally not subtle.2 Parasitic myopathy can occur from the invasion of skeletal muscle by trichinella after ingesting undercooked, infected meat.2 Although previously a more common problem, currently only 10 to 20 cases of trichinellosis are reported in the United States each year.17 Due to their rarity, bacterial, fungal, and parasitic myositides are not reviewed here.
Patients with a viral myositis often report prodromal symptoms such as fever, upper respiratory illness, or gastrointestinal distress one to 2 weeks before the onset of muscle complaints. Muscle pain is usually multifocal, involving larger, bilateral muscle groups, and may be associated with swelling.
Patients with viral myositis may exhibit diffusely painful, swollen, or boggy-feeling muscles as well as weakness and pain with exertion. Other signs of viral infection such as rash, fever, upper respiratory symptoms, or meningeal signs may be present. Severe signs include arrhythmia or respiratory failure due to cardiac muscle or diaphragm involvement, or signs of renal failure due to precipitation of myoglobin in the renal system (ie, rhabdomyolysis).2 If the infection affects the heart, patients may develop palpitations, pleuritic chest pain, or shortness of breath.2
Diagnosis of viral myositis relies heavily on clinical suspicion in patients with a fitting history and physical exam findings. Helpful lab tests include a complete blood count (CBC), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), creatine kinase (CK), and liver function tests (LFTs), all of which can be abnormal in viral myositis. Viral polymerase chain reaction, culture, or antigen testing may be helpful in severe or confusing cases, but in most cases such testing is unnecessary. Muscle biopsy is not recommended except in persistent cases, where definitive identification of the causative agent might alter treatment or when nonviral infection is suspected.2
Autoimmune myositic myopathy. Unlike infectious myopathies, autoimmune myopathies are usually chronic, subtle, and relatively rare. The 3 most common autoimmune myopathies—polymyositis, dermatomyositis, and inclusion body myositis—have a combined prevalence of approximately 10:100,000.6 Although these types of myopathies are uncommon, FPs will likely be the first to evaluate a patient with one of them.
Patients with an autoimmune myopathy typically complain of weakness and mild to moderate muscle pain, although pain may be absent. Compared to infectious myopathies, autoimmune myopathies usually exhibit a more indolent course. Patients with advanced disease may report fever, weight loss, shortness of breath from cardiomyopathy, heartburn from a weakened lower esophageal sphincter, and/or a rash.5
Physical examination may reveal symmetric, proximal muscle weakness. Atrophy is typically not seen until late in the disease. Skin exam usually is normal in patients with inclusion body myositis and polymyositis. The typical rash of dermatomyositis is a heliotrope (blue-purple) discoloration on the upper eyelids and a raised, violaceous, scaly eruption on the knuckles (Gottron’s papules).
Laboratory tests that can be helpful include CK, lactate dehydrogenase (LDH), aldolase, and LFTs (reflecting muscle injury, not liver involvement). For polymyositis and dermatomyositis, CK is the most sensitive lab test and often exhibits the highest elevation above normal.6 Conversely, CK is often normal or only mildly elevated in inclusion body myositis. Up to 80% of patients with autoimmune myopathy will have antinuclear antibodies.3,5 ESR and CRP levels are also often elevated.
Both electromyography (EMG) and muscle biopsy may be required to diagnose autoimmune myopathy, but these are typically done under the direction of a rheumatologist after an FP’s initial work-up is inconclusive.
Intrinsic myopathy: Suspect electrolyte problems, other causes
Intrinsic myopathy occurs in patients with electrolyte disorders, diseases of the endocrine system, or underlying metabolic dysfunction.
Electrolyte disorders. Muscle-related symptoms are unlikely to be the chief complaint of patients with severe electrolyte imbalance. However, a patient with mild to moderate electrolyte problems may develop muscle fatigue, weakness, or pain. TABLE 3 reviews other signs and symptoms of electrolyte abnormalities that may be helpful in establishing a diagnosis in a patient with muscle complaints.
Ordering a complete metabolic panel (CMP), CK, and urinalysis (UA) can help rule out electrolyte disorders. If electrolyte disorders are detected, an electrocardiogram is useful to evaluate for cardiac dysfunction. Once an electrolyte disorder is identified, investigate its underlying cause. Correcting the electrolyte disorder should help improve symptoms of myopathy.
Endocrine myopathy can be associated with hypothyroidism, hyperthyroidism, parathyroid disease, vitamin D deficiency, or Cushing syndrome.8-10,18,19 Although less common than some other causes, identifying endocrine myopathy is crucial because correcting the underlying disease will often improve multiple aspects of the patient’s health.
The presentation of endocrine myopathy may be subtle. Patients with hypothyroidism may experience muscle pain or weakness, fatigue, cold sensitivity, constipation, and dry skin.20 Muscle-related symptoms may be the only sign of endocrine myopathy in a patient who would otherwise be considered to have subclinical hypothyroidism.8,18 Hyperthyroidism can present with weight loss, heat intolerance, frequent bowel movements, tachycardia, and muscle weakness.21
Patients with parathyroid disease— especially patients with chronic renal failure—may report proximal muscle weakness, often in the lower extremities.19 Complaints of muscle weakness or pain can occur with severe vitamin D deficiency.10 Patients with Cushing syndrome often experience proximal weakness and weight gain.9
Patients with a personal or family history of endocrine disorders, previous thyroid surgery, or those taking medications that can impair thyroid function, such as lithium, amiodarone, or interferon, are at risk for endocrine myopathy.18-20 Suspect hyperparathyroidism in patients with chronic kidney disease who complain of weakness.
Vitamin D deficiency is relatively common, with at minimum 20% of elderly adults estimated to be deficient.10 Patients at risk for Cushing disease are most likely receiving pharmacologic doses of glucocorticoids, which can increase their risk of myopathy, or to have ectopic adrenocorticotropic hormone secretion.
Metabolic myopathy results from a lack of sufficient energy production in the muscle. The 3 main groups of metabolic myopathy are impaired muscle glycogenoses, disorders of fatty acid oxidation, and mitochondrial myopathies.7
Because metabolic myopathy can occur at any age, a thorough history and physical is crucial for diagnosis. Proximal weakness in metabolic myopathy is often associated with exercise intolerance, stressful illness, or fasting. Patients often present with dynamic abnormalities such as fatigue, muscle cramping, and even rhabdomyolysis during exertion.7
When evaluating patients you suspect may have metabolic myopathy, a physical exam may reveal muscle contractures, muscle swelling, or proximal muscle weakness. Patients with certain types of fatty acid oxidation disorders or mitochondrial disorders may also exhibit cardiomyopathy, neuropathy, retinopathy, ataxia, hearing loss, or other systemic manifestations.7
Basic labs for investigating suspected metabolic myopathy include serum electrolytes, glucose, LFTs, CK (which may or may not be elevated), lactate, ammonia, and UA for myoglobinuria. More advanced labs, such as serum total carnitine and acylcarnitine as well as urinary levels of dicarboxylic acids and acylglycines, may be needed if a metabolic disorder is strongly suspected.7 Muscle biopsy, EMG, and genetic testing can also prove helpful in diagnosis. Definitive diagnosis and treatment of metabolic myopathy usually requires a multidisciplinary team of providers, including subspecialty referral.
Toxic myopathy
Toxic myopathy refers to muscle damage caused by an exogenous chemical agent, most often a drug. The mechanism of toxicity is not always clear and may result from the activation of inflammatory responses similar to autoimmune myopathy.22 Toxic myopathies may result from several commonly used medications; cholesterol-lowering medications are a common culprit.13-15,23-25 Drug-induced myopathies vary in frequency and severity. For instance, in patients taking statins, the rate of myalgias is 6%, while the incidence of rhabdomyolysis is estimated to be 4 per 100,000, and is found most often in patients taking concomitant fibrates.23
Drug-induced toxic myopathy differs from previously discussed myopathies in that symptoms are usually more insidious, findings on exam are more often mixed muscular and neurologic, and lab abnormalities are usually more subtle.11,12 Symptoms of myopathy typically occur weeks or months after initiating a drug and usually improve or resolve within weeks after discontinuing the offending agent. Knowing the patient’s medication list and which medications cause certain patterns of myopathy symptoms can help guide the differential diagnosis (TABLE 411-15,22-25).
Risk factors for most medication-related myopathies are polypharmacy, renal or liver disease, and age over 50 years13-15,23-25 The physical exam for patients with drug- or toxin-related myopathy will most often reveal relatively minor abnormalities such as muscle tenderness and mild weakness, except for the most severe or advanced cases. Most patients will not have physical signs that suggest an underlying illness. CK levels and LFTs should be obtained. Basic chemistry and UA may also be helpful in patients with risk factors for renal disease.
CASE › Ms. C has been taking a statin for more than 10 years, and the dose was recently increased. You are aware that statin-related muscle injury can develop even after years of use, and suspect the statin may be causing her myopathy. You order a CK test, which is mildly elevated. You recommend discontinuing the statin. After 8 weeks off her statin, Ms. C’s Symptoms do not improve. Given her lack of systemic complaints, myositic myopathy from an infectious or rheumatologic cause seems unlikely. You begin to consider an intrinsic cause of myopathy, and order the following tests: a CMP, UA, thyroid-stimulating hormone, repeat CK, and vitamin D level. This testing reveals a vitamin D deficiency at 17 ng/ml (normal range: 30-74 ng/ml). You recommend vitamin D, 50,000 IU per week for 8 weeks. At follow-up, Ms. C's vitamin D level is 40. She says she feels better and her muscle complaints have resolved.
CORRESPONDENCE
Brent W. Smith, MD, Travis Air Force Base Family Medicine Residency, 101 Bodin Circle, Travis Air Force Base, CA 94535; smithb@smithnet.us
1. Huynh CN, Yanni LM, Morgan LA. Fibromyalgia: diagnosis and management for the primary healthcare provider. J Womens Health. 2008;8:1379-1387.
2. Crum-Cianflone NF. Bacterial, fungal, parasitic, and viral myositis. Clin Microbiol Rev. 2008;21:473-494.
3. Reichlin M, Arnett FC Jr. Multiplicity of antibodies in myositis sera. Arthritis Rheum. 1984;27:1150-1156.
4. Yoshino M, Suzuki S, Adachi K, et al. High incidence of acute myositis with type A influenza virus infection in the elderly. Intern Med. 2000;39:431-432.
5. Dalakas MC, Hohlfeld R. Polymyositis and dermatomyositis. Lancet. 2003;362:971-982.
6. Wilson FC, Ytterberg SR, St Sauver JL, et al. Epidemiology of sporadic inclusion body myositis and polymyositis in Olmsted County, Minnesota. J Rheumatol. 2008;35:445-447.
7. Smith EC, El-Gharbawy A, Koeberl DD. Metabolic myopathies: clinical features and diagnostic approach. Rheum Dis Clin N Am. 2011:37:201-217.
8. Reuters V, Teixeira Pde F, Vigário PS, et al. Functional capacity and muscular abnormalities in subclinical hypothyroidism. Am J Med Sci. 2009;338:259-263.
9. Nieman LK, Biller BM, Findling JW, et al. The diagnosis of Cushing’s syndrome: an Endocrine Society clinical practice guideline. J Clin Endocrinol Metab. 2008;93:1526-1540.
10. Holick MF, Binkley NC, Bischoff-Ferrari HA, et al; Endocrine Society. Evaluation, treatment, and prevention of vitamin D deficiency: an Endocrine Society clinical practice guideline. J Clin Endocrinol Metab. 2011;96:1911-1930.
11. Antons KA, Williams CD, Baker SK, et al. Clinical perspectives of statin-induced rhabdomyolysis. Am J Med. 2006;119:400-409.
12. Phillips PS, Haas RH, Bannykh S, et al; Scripps Mercy Clinical Research Center. Statin-associated myopathy with normal creatine kinase levels. Ann Intern Med. 2002;137:581-585.
13. Pereira RM, Freire de Carvalho J. Glucocorticoid-induced myopathy. Joint Bone Spine. 2011;78:41-44.
14. Posada C, García-Cruz A, García-Doval I, et al. Chloroquine-induced myopathy. Lupus. 2011;20:773-774.
15. Uri DS, Biavis M. Colchicine neuromyopathy. J Clin Rheumatol. 1996;2:163-166.
16. Mannix R, Tan ML, Wright R, et al. Acute pediatric rhabdomyolysis: causes and rates of renal failure. Pediatrics. 2006;118:2119-2125.
17. Pozio E. World distribution of Trichinella spp. infections in animals and humans. Vet Parasitol. 2007;149:3-21.
18. Rodolico C, Toscano A, Benvenga S, et al. Myopathy as the persistently isolated symptomatology of primary autoimmune hypothyroidism. Thyroid.1998;8:1033-1038.
19. AACE/AAES Task Force on Primary Hyperparathyroidism. The American Association of Clinical Endocrinologists and The American Association of Endocrine Surgeons position statement on the diagnosis and management of primary hyperparathyroidism. Endocr Pract. 2005;11:49-54.
20. Garber JR, Cobin RH, Gharib H, et al; American Association of Clinical Endocrinologists and American Thyroid Association Taskforce on Hypothyroidism in Adults. Clinical practice guidelines for hypothyroidism in adults: cosponsored by the American Association of Clinical Endocrinologists and the American Thyroid Association. Endocrine Pract. 2012;18:988-1028.
21. Bahn Chair RS, Burch HB, Cooper DS, et al; American Thyroid Association; American Association of Clinical Endocrinologists. Hyperthyroidism and other causes of thyrotoxicosis: management guidelines of the American Thyroid Association and American Association of Clinical Endocrinologists. Thyroid. 2011;21:593-646.
22. Mammen AL, Amato AA. Statin myopathy: a review of recent progress. Curr Opin Rheumatol. 2010;22:644-650.
23. Buettner C, Davis RB, Leveille SG, et al. Prevalence of musculoskeletal pain and statin use. J Gen Intern Med. 2008;23: 1182-1186.
24. Marot A, Morelle J, Chouinard VA, et al. Concomitant use of simvastatin and amiodarone resulting in severe rhabdomyolysis: a case report and review of the literature. Acta Clin Belg. 2011;66:134-136.
25. Peters BS, Winer J, Landon DN, et al. Mitochondrial myopathy associated with chronic zidovudine therapy in AIDS. Q J Med. 1993;86:5-15.
› Categorize patients with muscle complaints into suspected myositic, intrinsic, or toxic myopathy to help guide subsequent work-up. C
› Look for diffusely painful, swollen, or boggy-feeling muscles—as well as weakness and pain with exertion—in patients you suspect may have viral myopathy. C
› Consider electromyography and muscle biopsy for patients you suspect may have dermatomyositis. C
Strength of recommendation (SOR)
A Good-quality patient-oriented evidence
B Inconsistent or limited-quality patient-oriented evidence
C Consensus, usual practice, opinion, disease-oriented evidence, case series
CASE › Marie C, a 75-year-old Asian woman, reports weakness in her legs and arms with unsteadiness when walking. She has a vague but persistent ache in her large muscles. Her symptoms have developed slowly over the past 3 months. She denies recent signs or symptoms of infection or other illness. Her medical history includes hypertension, hyperlipidemia, osteopenia, and obesity. Ms. C takes lisinopril 10 mg/d and atorvastatin, which was recently increased from 10 to 20 mg/d.
What would your next steps be in caring for this patient?
Patients who experience muscle-related symptoms such as pain, fatigue, or weakness often seek help from their family physician (FP). The list of possible causes of these complaints can be lengthy and vary greatly, from nonmyopathic conditions such as fibromyalgia to worrisome forms of myopathy such as inclusion body myositis or polymyositis. This article will help you to quickly identify which patients with muscle-related complaints should be evaluated for myopathy and what your work-up should include.
Myopathy or not?
Distinguishing between myopathy and nonmyopathic muscle pain or weakness is the first step in evaluating patients with muscle-related complaints. Many conditions share muscle-related symptoms, but actual muscle damage is not always present (eg, fibromyalgia, chronic pain, and chronic fatigue syndromes).1 While there is some overlap in presentation between patients with myopathy and nonmyopathic conditions, there are important differences in symptoms, physical exam findings, and lab test results (TABLE 11-4). Notably, in myopathic disease, patients’ symptoms are usually progressive, vital signs are abnormal, and weakness is common, whereas patients with nonmyopathic disease typically have remitting and relapsing symptoms, normal vital signs, and no weakness.
Myopathy itself is divided into 3 categories—myositic, intrinsic, and toxic—which reflect the condition, or medication, that brought on the muscle damage (TABLE 22,4-15). Placing patients into one of these categories based on their risk factors, history, and physical exam findings can help to focus the diagnostic work-up on areas most likely to provide useful information.
Myositic myopathy can be caused by infection or autoimmunity
Myositic myopathies result in inflammatory destruction of muscle tissue. Patients with myositic myopathy often exhibit fever, malaise, weight loss, and general fatigue. Though weakness and pain are common, both can be variable or even absent in myositic myopathy.2,5 Myositic myopathy can be caused by infectious agents or can develop from an autoimmune disease.
Infectious myositic myopathy is one of the more common types of myopathy that FPs will encounter.2 Viruses such as influenza, parainfluenza, coxsackievirus, human immunodeficiency virus, cytomegalovirus, echovirus, adenovirus, Epstein-Barr, and hepatitis C are common causes.2,4,16 Bacterial and fungal myositides are relatively rare. Both most often occur as the result of penetrating trauma or immunocompromise, and are generally not subtle.2 Parasitic myopathy can occur from the invasion of skeletal muscle by trichinella after ingesting undercooked, infected meat.2 Although previously a more common problem, currently only 10 to 20 cases of trichinellosis are reported in the United States each year.17 Due to their rarity, bacterial, fungal, and parasitic myositides are not reviewed here.
Patients with a viral myositis often report prodromal symptoms such as fever, upper respiratory illness, or gastrointestinal distress one to 2 weeks before the onset of muscle complaints. Muscle pain is usually multifocal, involving larger, bilateral muscle groups, and may be associated with swelling.
Patients with viral myositis may exhibit diffusely painful, swollen, or boggy-feeling muscles as well as weakness and pain with exertion. Other signs of viral infection such as rash, fever, upper respiratory symptoms, or meningeal signs may be present. Severe signs include arrhythmia or respiratory failure due to cardiac muscle or diaphragm involvement, or signs of renal failure due to precipitation of myoglobin in the renal system (ie, rhabdomyolysis).2 If the infection affects the heart, patients may develop palpitations, pleuritic chest pain, or shortness of breath.2
Diagnosis of viral myositis relies heavily on clinical suspicion in patients with a fitting history and physical exam findings. Helpful lab tests include a complete blood count (CBC), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), creatine kinase (CK), and liver function tests (LFTs), all of which can be abnormal in viral myositis. Viral polymerase chain reaction, culture, or antigen testing may be helpful in severe or confusing cases, but in most cases such testing is unnecessary. Muscle biopsy is not recommended except in persistent cases, where definitive identification of the causative agent might alter treatment or when nonviral infection is suspected.2
Autoimmune myositic myopathy. Unlike infectious myopathies, autoimmune myopathies are usually chronic, subtle, and relatively rare. The 3 most common autoimmune myopathies—polymyositis, dermatomyositis, and inclusion body myositis—have a combined prevalence of approximately 10:100,000.6 Although these types of myopathies are uncommon, FPs will likely be the first to evaluate a patient with one of them.
Patients with an autoimmune myopathy typically complain of weakness and mild to moderate muscle pain, although pain may be absent. Compared to infectious myopathies, autoimmune myopathies usually exhibit a more indolent course. Patients with advanced disease may report fever, weight loss, shortness of breath from cardiomyopathy, heartburn from a weakened lower esophageal sphincter, and/or a rash.5
Physical examination may reveal symmetric, proximal muscle weakness. Atrophy is typically not seen until late in the disease. Skin exam usually is normal in patients with inclusion body myositis and polymyositis. The typical rash of dermatomyositis is a heliotrope (blue-purple) discoloration on the upper eyelids and a raised, violaceous, scaly eruption on the knuckles (Gottron’s papules).
Laboratory tests that can be helpful include CK, lactate dehydrogenase (LDH), aldolase, and LFTs (reflecting muscle injury, not liver involvement). For polymyositis and dermatomyositis, CK is the most sensitive lab test and often exhibits the highest elevation above normal.6 Conversely, CK is often normal or only mildly elevated in inclusion body myositis. Up to 80% of patients with autoimmune myopathy will have antinuclear antibodies.3,5 ESR and CRP levels are also often elevated.
Both electromyography (EMG) and muscle biopsy may be required to diagnose autoimmune myopathy, but these are typically done under the direction of a rheumatologist after an FP’s initial work-up is inconclusive.
Intrinsic myopathy: Suspect electrolyte problems, other causes
Intrinsic myopathy occurs in patients with electrolyte disorders, diseases of the endocrine system, or underlying metabolic dysfunction.
Electrolyte disorders. Muscle-related symptoms are unlikely to be the chief complaint of patients with severe electrolyte imbalance. However, a patient with mild to moderate electrolyte problems may develop muscle fatigue, weakness, or pain. TABLE 3 reviews other signs and symptoms of electrolyte abnormalities that may be helpful in establishing a diagnosis in a patient with muscle complaints.
Ordering a complete metabolic panel (CMP), CK, and urinalysis (UA) can help rule out electrolyte disorders. If electrolyte disorders are detected, an electrocardiogram is useful to evaluate for cardiac dysfunction. Once an electrolyte disorder is identified, investigate its underlying cause. Correcting the electrolyte disorder should help improve symptoms of myopathy.
Endocrine myopathy can be associated with hypothyroidism, hyperthyroidism, parathyroid disease, vitamin D deficiency, or Cushing syndrome.8-10,18,19 Although less common than some other causes, identifying endocrine myopathy is crucial because correcting the underlying disease will often improve multiple aspects of the patient’s health.
The presentation of endocrine myopathy may be subtle. Patients with hypothyroidism may experience muscle pain or weakness, fatigue, cold sensitivity, constipation, and dry skin.20 Muscle-related symptoms may be the only sign of endocrine myopathy in a patient who would otherwise be considered to have subclinical hypothyroidism.8,18 Hyperthyroidism can present with weight loss, heat intolerance, frequent bowel movements, tachycardia, and muscle weakness.21
Patients with parathyroid disease— especially patients with chronic renal failure—may report proximal muscle weakness, often in the lower extremities.19 Complaints of muscle weakness or pain can occur with severe vitamin D deficiency.10 Patients with Cushing syndrome often experience proximal weakness and weight gain.9
Patients with a personal or family history of endocrine disorders, previous thyroid surgery, or those taking medications that can impair thyroid function, such as lithium, amiodarone, or interferon, are at risk for endocrine myopathy.18-20 Suspect hyperparathyroidism in patients with chronic kidney disease who complain of weakness.
Vitamin D deficiency is relatively common, with at minimum 20% of elderly adults estimated to be deficient.10 Patients at risk for Cushing disease are most likely receiving pharmacologic doses of glucocorticoids, which can increase their risk of myopathy, or to have ectopic adrenocorticotropic hormone secretion.
Metabolic myopathy results from a lack of sufficient energy production in the muscle. The 3 main groups of metabolic myopathy are impaired muscle glycogenoses, disorders of fatty acid oxidation, and mitochondrial myopathies.7
Because metabolic myopathy can occur at any age, a thorough history and physical is crucial for diagnosis. Proximal weakness in metabolic myopathy is often associated with exercise intolerance, stressful illness, or fasting. Patients often present with dynamic abnormalities such as fatigue, muscle cramping, and even rhabdomyolysis during exertion.7
When evaluating patients you suspect may have metabolic myopathy, a physical exam may reveal muscle contractures, muscle swelling, or proximal muscle weakness. Patients with certain types of fatty acid oxidation disorders or mitochondrial disorders may also exhibit cardiomyopathy, neuropathy, retinopathy, ataxia, hearing loss, or other systemic manifestations.7
Basic labs for investigating suspected metabolic myopathy include serum electrolytes, glucose, LFTs, CK (which may or may not be elevated), lactate, ammonia, and UA for myoglobinuria. More advanced labs, such as serum total carnitine and acylcarnitine as well as urinary levels of dicarboxylic acids and acylglycines, may be needed if a metabolic disorder is strongly suspected.7 Muscle biopsy, EMG, and genetic testing can also prove helpful in diagnosis. Definitive diagnosis and treatment of metabolic myopathy usually requires a multidisciplinary team of providers, including subspecialty referral.
Toxic myopathy
Toxic myopathy refers to muscle damage caused by an exogenous chemical agent, most often a drug. The mechanism of toxicity is not always clear and may result from the activation of inflammatory responses similar to autoimmune myopathy.22 Toxic myopathies may result from several commonly used medications; cholesterol-lowering medications are a common culprit.13-15,23-25 Drug-induced myopathies vary in frequency and severity. For instance, in patients taking statins, the rate of myalgias is 6%, while the incidence of rhabdomyolysis is estimated to be 4 per 100,000, and is found most often in patients taking concomitant fibrates.23
Drug-induced toxic myopathy differs from previously discussed myopathies in that symptoms are usually more insidious, findings on exam are more often mixed muscular and neurologic, and lab abnormalities are usually more subtle.11,12 Symptoms of myopathy typically occur weeks or months after initiating a drug and usually improve or resolve within weeks after discontinuing the offending agent. Knowing the patient’s medication list and which medications cause certain patterns of myopathy symptoms can help guide the differential diagnosis (TABLE 411-15,22-25).
Risk factors for most medication-related myopathies are polypharmacy, renal or liver disease, and age over 50 years13-15,23-25 The physical exam for patients with drug- or toxin-related myopathy will most often reveal relatively minor abnormalities such as muscle tenderness and mild weakness, except for the most severe or advanced cases. Most patients will not have physical signs that suggest an underlying illness. CK levels and LFTs should be obtained. Basic chemistry and UA may also be helpful in patients with risk factors for renal disease.
CASE › Ms. C has been taking a statin for more than 10 years, and the dose was recently increased. You are aware that statin-related muscle injury can develop even after years of use, and suspect the statin may be causing her myopathy. You order a CK test, which is mildly elevated. You recommend discontinuing the statin. After 8 weeks off her statin, Ms. C’s Symptoms do not improve. Given her lack of systemic complaints, myositic myopathy from an infectious or rheumatologic cause seems unlikely. You begin to consider an intrinsic cause of myopathy, and order the following tests: a CMP, UA, thyroid-stimulating hormone, repeat CK, and vitamin D level. This testing reveals a vitamin D deficiency at 17 ng/ml (normal range: 30-74 ng/ml). You recommend vitamin D, 50,000 IU per week for 8 weeks. At follow-up, Ms. C's vitamin D level is 40. She says she feels better and her muscle complaints have resolved.
CORRESPONDENCE
Brent W. Smith, MD, Travis Air Force Base Family Medicine Residency, 101 Bodin Circle, Travis Air Force Base, CA 94535; smithb@smithnet.us
› Categorize patients with muscle complaints into suspected myositic, intrinsic, or toxic myopathy to help guide subsequent work-up. C
› Look for diffusely painful, swollen, or boggy-feeling muscles—as well as weakness and pain with exertion—in patients you suspect may have viral myopathy. C
› Consider electromyography and muscle biopsy for patients you suspect may have dermatomyositis. C
Strength of recommendation (SOR)
A Good-quality patient-oriented evidence
B Inconsistent or limited-quality patient-oriented evidence
C Consensus, usual practice, opinion, disease-oriented evidence, case series
CASE › Marie C, a 75-year-old Asian woman, reports weakness in her legs and arms with unsteadiness when walking. She has a vague but persistent ache in her large muscles. Her symptoms have developed slowly over the past 3 months. She denies recent signs or symptoms of infection or other illness. Her medical history includes hypertension, hyperlipidemia, osteopenia, and obesity. Ms. C takes lisinopril 10 mg/d and atorvastatin, which was recently increased from 10 to 20 mg/d.
What would your next steps be in caring for this patient?
Patients who experience muscle-related symptoms such as pain, fatigue, or weakness often seek help from their family physician (FP). The list of possible causes of these complaints can be lengthy and vary greatly, from nonmyopathic conditions such as fibromyalgia to worrisome forms of myopathy such as inclusion body myositis or polymyositis. This article will help you to quickly identify which patients with muscle-related complaints should be evaluated for myopathy and what your work-up should include.
Myopathy or not?
Distinguishing between myopathy and nonmyopathic muscle pain or weakness is the first step in evaluating patients with muscle-related complaints. Many conditions share muscle-related symptoms, but actual muscle damage is not always present (eg, fibromyalgia, chronic pain, and chronic fatigue syndromes).1 While there is some overlap in presentation between patients with myopathy and nonmyopathic conditions, there are important differences in symptoms, physical exam findings, and lab test results (TABLE 11-4). Notably, in myopathic disease, patients’ symptoms are usually progressive, vital signs are abnormal, and weakness is common, whereas patients with nonmyopathic disease typically have remitting and relapsing symptoms, normal vital signs, and no weakness.
Myopathy itself is divided into 3 categories—myositic, intrinsic, and toxic—which reflect the condition, or medication, that brought on the muscle damage (TABLE 22,4-15). Placing patients into one of these categories based on their risk factors, history, and physical exam findings can help to focus the diagnostic work-up on areas most likely to provide useful information.
Myositic myopathy can be caused by infection or autoimmunity
Myositic myopathies result in inflammatory destruction of muscle tissue. Patients with myositic myopathy often exhibit fever, malaise, weight loss, and general fatigue. Though weakness and pain are common, both can be variable or even absent in myositic myopathy.2,5 Myositic myopathy can be caused by infectious agents or can develop from an autoimmune disease.
Infectious myositic myopathy is one of the more common types of myopathy that FPs will encounter.2 Viruses such as influenza, parainfluenza, coxsackievirus, human immunodeficiency virus, cytomegalovirus, echovirus, adenovirus, Epstein-Barr, and hepatitis C are common causes.2,4,16 Bacterial and fungal myositides are relatively rare. Both most often occur as the result of penetrating trauma or immunocompromise, and are generally not subtle.2 Parasitic myopathy can occur from the invasion of skeletal muscle by trichinella after ingesting undercooked, infected meat.2 Although previously a more common problem, currently only 10 to 20 cases of trichinellosis are reported in the United States each year.17 Due to their rarity, bacterial, fungal, and parasitic myositides are not reviewed here.
Patients with a viral myositis often report prodromal symptoms such as fever, upper respiratory illness, or gastrointestinal distress one to 2 weeks before the onset of muscle complaints. Muscle pain is usually multifocal, involving larger, bilateral muscle groups, and may be associated with swelling.
Patients with viral myositis may exhibit diffusely painful, swollen, or boggy-feeling muscles as well as weakness and pain with exertion. Other signs of viral infection such as rash, fever, upper respiratory symptoms, or meningeal signs may be present. Severe signs include arrhythmia or respiratory failure due to cardiac muscle or diaphragm involvement, or signs of renal failure due to precipitation of myoglobin in the renal system (ie, rhabdomyolysis).2 If the infection affects the heart, patients may develop palpitations, pleuritic chest pain, or shortness of breath.2
Diagnosis of viral myositis relies heavily on clinical suspicion in patients with a fitting history and physical exam findings. Helpful lab tests include a complete blood count (CBC), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), creatine kinase (CK), and liver function tests (LFTs), all of which can be abnormal in viral myositis. Viral polymerase chain reaction, culture, or antigen testing may be helpful in severe or confusing cases, but in most cases such testing is unnecessary. Muscle biopsy is not recommended except in persistent cases, where definitive identification of the causative agent might alter treatment or when nonviral infection is suspected.2
Autoimmune myositic myopathy. Unlike infectious myopathies, autoimmune myopathies are usually chronic, subtle, and relatively rare. The 3 most common autoimmune myopathies—polymyositis, dermatomyositis, and inclusion body myositis—have a combined prevalence of approximately 10:100,000.6 Although these types of myopathies are uncommon, FPs will likely be the first to evaluate a patient with one of them.
Patients with an autoimmune myopathy typically complain of weakness and mild to moderate muscle pain, although pain may be absent. Compared to infectious myopathies, autoimmune myopathies usually exhibit a more indolent course. Patients with advanced disease may report fever, weight loss, shortness of breath from cardiomyopathy, heartburn from a weakened lower esophageal sphincter, and/or a rash.5
Physical examination may reveal symmetric, proximal muscle weakness. Atrophy is typically not seen until late in the disease. Skin exam usually is normal in patients with inclusion body myositis and polymyositis. The typical rash of dermatomyositis is a heliotrope (blue-purple) discoloration on the upper eyelids and a raised, violaceous, scaly eruption on the knuckles (Gottron’s papules).
Laboratory tests that can be helpful include CK, lactate dehydrogenase (LDH), aldolase, and LFTs (reflecting muscle injury, not liver involvement). For polymyositis and dermatomyositis, CK is the most sensitive lab test and often exhibits the highest elevation above normal.6 Conversely, CK is often normal or only mildly elevated in inclusion body myositis. Up to 80% of patients with autoimmune myopathy will have antinuclear antibodies.3,5 ESR and CRP levels are also often elevated.
Both electromyography (EMG) and muscle biopsy may be required to diagnose autoimmune myopathy, but these are typically done under the direction of a rheumatologist after an FP’s initial work-up is inconclusive.
Intrinsic myopathy: Suspect electrolyte problems, other causes
Intrinsic myopathy occurs in patients with electrolyte disorders, diseases of the endocrine system, or underlying metabolic dysfunction.
Electrolyte disorders. Muscle-related symptoms are unlikely to be the chief complaint of patients with severe electrolyte imbalance. However, a patient with mild to moderate electrolyte problems may develop muscle fatigue, weakness, or pain. TABLE 3 reviews other signs and symptoms of electrolyte abnormalities that may be helpful in establishing a diagnosis in a patient with muscle complaints.
Ordering a complete metabolic panel (CMP), CK, and urinalysis (UA) can help rule out electrolyte disorders. If electrolyte disorders are detected, an electrocardiogram is useful to evaluate for cardiac dysfunction. Once an electrolyte disorder is identified, investigate its underlying cause. Correcting the electrolyte disorder should help improve symptoms of myopathy.
Endocrine myopathy can be associated with hypothyroidism, hyperthyroidism, parathyroid disease, vitamin D deficiency, or Cushing syndrome.8-10,18,19 Although less common than some other causes, identifying endocrine myopathy is crucial because correcting the underlying disease will often improve multiple aspects of the patient’s health.
The presentation of endocrine myopathy may be subtle. Patients with hypothyroidism may experience muscle pain or weakness, fatigue, cold sensitivity, constipation, and dry skin.20 Muscle-related symptoms may be the only sign of endocrine myopathy in a patient who would otherwise be considered to have subclinical hypothyroidism.8,18 Hyperthyroidism can present with weight loss, heat intolerance, frequent bowel movements, tachycardia, and muscle weakness.21
Patients with parathyroid disease— especially patients with chronic renal failure—may report proximal muscle weakness, often in the lower extremities.19 Complaints of muscle weakness or pain can occur with severe vitamin D deficiency.10 Patients with Cushing syndrome often experience proximal weakness and weight gain.9
Patients with a personal or family history of endocrine disorders, previous thyroid surgery, or those taking medications that can impair thyroid function, such as lithium, amiodarone, or interferon, are at risk for endocrine myopathy.18-20 Suspect hyperparathyroidism in patients with chronic kidney disease who complain of weakness.
Vitamin D deficiency is relatively common, with at minimum 20% of elderly adults estimated to be deficient.10 Patients at risk for Cushing disease are most likely receiving pharmacologic doses of glucocorticoids, which can increase their risk of myopathy, or to have ectopic adrenocorticotropic hormone secretion.
Metabolic myopathy results from a lack of sufficient energy production in the muscle. The 3 main groups of metabolic myopathy are impaired muscle glycogenoses, disorders of fatty acid oxidation, and mitochondrial myopathies.7
Because metabolic myopathy can occur at any age, a thorough history and physical is crucial for diagnosis. Proximal weakness in metabolic myopathy is often associated with exercise intolerance, stressful illness, or fasting. Patients often present with dynamic abnormalities such as fatigue, muscle cramping, and even rhabdomyolysis during exertion.7
When evaluating patients you suspect may have metabolic myopathy, a physical exam may reveal muscle contractures, muscle swelling, or proximal muscle weakness. Patients with certain types of fatty acid oxidation disorders or mitochondrial disorders may also exhibit cardiomyopathy, neuropathy, retinopathy, ataxia, hearing loss, or other systemic manifestations.7
Basic labs for investigating suspected metabolic myopathy include serum electrolytes, glucose, LFTs, CK (which may or may not be elevated), lactate, ammonia, and UA for myoglobinuria. More advanced labs, such as serum total carnitine and acylcarnitine as well as urinary levels of dicarboxylic acids and acylglycines, may be needed if a metabolic disorder is strongly suspected.7 Muscle biopsy, EMG, and genetic testing can also prove helpful in diagnosis. Definitive diagnosis and treatment of metabolic myopathy usually requires a multidisciplinary team of providers, including subspecialty referral.
Toxic myopathy
Toxic myopathy refers to muscle damage caused by an exogenous chemical agent, most often a drug. The mechanism of toxicity is not always clear and may result from the activation of inflammatory responses similar to autoimmune myopathy.22 Toxic myopathies may result from several commonly used medications; cholesterol-lowering medications are a common culprit.13-15,23-25 Drug-induced myopathies vary in frequency and severity. For instance, in patients taking statins, the rate of myalgias is 6%, while the incidence of rhabdomyolysis is estimated to be 4 per 100,000, and is found most often in patients taking concomitant fibrates.23
Drug-induced toxic myopathy differs from previously discussed myopathies in that symptoms are usually more insidious, findings on exam are more often mixed muscular and neurologic, and lab abnormalities are usually more subtle.11,12 Symptoms of myopathy typically occur weeks or months after initiating a drug and usually improve or resolve within weeks after discontinuing the offending agent. Knowing the patient’s medication list and which medications cause certain patterns of myopathy symptoms can help guide the differential diagnosis (TABLE 411-15,22-25).
Risk factors for most medication-related myopathies are polypharmacy, renal or liver disease, and age over 50 years13-15,23-25 The physical exam for patients with drug- or toxin-related myopathy will most often reveal relatively minor abnormalities such as muscle tenderness and mild weakness, except for the most severe or advanced cases. Most patients will not have physical signs that suggest an underlying illness. CK levels and LFTs should be obtained. Basic chemistry and UA may also be helpful in patients with risk factors for renal disease.
CASE › Ms. C has been taking a statin for more than 10 years, and the dose was recently increased. You are aware that statin-related muscle injury can develop even after years of use, and suspect the statin may be causing her myopathy. You order a CK test, which is mildly elevated. You recommend discontinuing the statin. After 8 weeks off her statin, Ms. C’s Symptoms do not improve. Given her lack of systemic complaints, myositic myopathy from an infectious or rheumatologic cause seems unlikely. You begin to consider an intrinsic cause of myopathy, and order the following tests: a CMP, UA, thyroid-stimulating hormone, repeat CK, and vitamin D level. This testing reveals a vitamin D deficiency at 17 ng/ml (normal range: 30-74 ng/ml). You recommend vitamin D, 50,000 IU per week for 8 weeks. At follow-up, Ms. C's vitamin D level is 40. She says she feels better and her muscle complaints have resolved.
CORRESPONDENCE
Brent W. Smith, MD, Travis Air Force Base Family Medicine Residency, 101 Bodin Circle, Travis Air Force Base, CA 94535; smithb@smithnet.us
1. Huynh CN, Yanni LM, Morgan LA. Fibromyalgia: diagnosis and management for the primary healthcare provider. J Womens Health. 2008;8:1379-1387.
2. Crum-Cianflone NF. Bacterial, fungal, parasitic, and viral myositis. Clin Microbiol Rev. 2008;21:473-494.
3. Reichlin M, Arnett FC Jr. Multiplicity of antibodies in myositis sera. Arthritis Rheum. 1984;27:1150-1156.
4. Yoshino M, Suzuki S, Adachi K, et al. High incidence of acute myositis with type A influenza virus infection in the elderly. Intern Med. 2000;39:431-432.
5. Dalakas MC, Hohlfeld R. Polymyositis and dermatomyositis. Lancet. 2003;362:971-982.
6. Wilson FC, Ytterberg SR, St Sauver JL, et al. Epidemiology of sporadic inclusion body myositis and polymyositis in Olmsted County, Minnesota. J Rheumatol. 2008;35:445-447.
7. Smith EC, El-Gharbawy A, Koeberl DD. Metabolic myopathies: clinical features and diagnostic approach. Rheum Dis Clin N Am. 2011:37:201-217.
8. Reuters V, Teixeira Pde F, Vigário PS, et al. Functional capacity and muscular abnormalities in subclinical hypothyroidism. Am J Med Sci. 2009;338:259-263.
9. Nieman LK, Biller BM, Findling JW, et al. The diagnosis of Cushing’s syndrome: an Endocrine Society clinical practice guideline. J Clin Endocrinol Metab. 2008;93:1526-1540.
10. Holick MF, Binkley NC, Bischoff-Ferrari HA, et al; Endocrine Society. Evaluation, treatment, and prevention of vitamin D deficiency: an Endocrine Society clinical practice guideline. J Clin Endocrinol Metab. 2011;96:1911-1930.
11. Antons KA, Williams CD, Baker SK, et al. Clinical perspectives of statin-induced rhabdomyolysis. Am J Med. 2006;119:400-409.
12. Phillips PS, Haas RH, Bannykh S, et al; Scripps Mercy Clinical Research Center. Statin-associated myopathy with normal creatine kinase levels. Ann Intern Med. 2002;137:581-585.
13. Pereira RM, Freire de Carvalho J. Glucocorticoid-induced myopathy. Joint Bone Spine. 2011;78:41-44.
14. Posada C, García-Cruz A, García-Doval I, et al. Chloroquine-induced myopathy. Lupus. 2011;20:773-774.
15. Uri DS, Biavis M. Colchicine neuromyopathy. J Clin Rheumatol. 1996;2:163-166.
16. Mannix R, Tan ML, Wright R, et al. Acute pediatric rhabdomyolysis: causes and rates of renal failure. Pediatrics. 2006;118:2119-2125.
17. Pozio E. World distribution of Trichinella spp. infections in animals and humans. Vet Parasitol. 2007;149:3-21.
18. Rodolico C, Toscano A, Benvenga S, et al. Myopathy as the persistently isolated symptomatology of primary autoimmune hypothyroidism. Thyroid.1998;8:1033-1038.
19. AACE/AAES Task Force on Primary Hyperparathyroidism. The American Association of Clinical Endocrinologists and The American Association of Endocrine Surgeons position statement on the diagnosis and management of primary hyperparathyroidism. Endocr Pract. 2005;11:49-54.
20. Garber JR, Cobin RH, Gharib H, et al; American Association of Clinical Endocrinologists and American Thyroid Association Taskforce on Hypothyroidism in Adults. Clinical practice guidelines for hypothyroidism in adults: cosponsored by the American Association of Clinical Endocrinologists and the American Thyroid Association. Endocrine Pract. 2012;18:988-1028.
21. Bahn Chair RS, Burch HB, Cooper DS, et al; American Thyroid Association; American Association of Clinical Endocrinologists. Hyperthyroidism and other causes of thyrotoxicosis: management guidelines of the American Thyroid Association and American Association of Clinical Endocrinologists. Thyroid. 2011;21:593-646.
22. Mammen AL, Amato AA. Statin myopathy: a review of recent progress. Curr Opin Rheumatol. 2010;22:644-650.
23. Buettner C, Davis RB, Leveille SG, et al. Prevalence of musculoskeletal pain and statin use. J Gen Intern Med. 2008;23: 1182-1186.
24. Marot A, Morelle J, Chouinard VA, et al. Concomitant use of simvastatin and amiodarone resulting in severe rhabdomyolysis: a case report and review of the literature. Acta Clin Belg. 2011;66:134-136.
25. Peters BS, Winer J, Landon DN, et al. Mitochondrial myopathy associated with chronic zidovudine therapy in AIDS. Q J Med. 1993;86:5-15.
1. Huynh CN, Yanni LM, Morgan LA. Fibromyalgia: diagnosis and management for the primary healthcare provider. J Womens Health. 2008;8:1379-1387.
2. Crum-Cianflone NF. Bacterial, fungal, parasitic, and viral myositis. Clin Microbiol Rev. 2008;21:473-494.
3. Reichlin M, Arnett FC Jr. Multiplicity of antibodies in myositis sera. Arthritis Rheum. 1984;27:1150-1156.
4. Yoshino M, Suzuki S, Adachi K, et al. High incidence of acute myositis with type A influenza virus infection in the elderly. Intern Med. 2000;39:431-432.
5. Dalakas MC, Hohlfeld R. Polymyositis and dermatomyositis. Lancet. 2003;362:971-982.
6. Wilson FC, Ytterberg SR, St Sauver JL, et al. Epidemiology of sporadic inclusion body myositis and polymyositis in Olmsted County, Minnesota. J Rheumatol. 2008;35:445-447.
7. Smith EC, El-Gharbawy A, Koeberl DD. Metabolic myopathies: clinical features and diagnostic approach. Rheum Dis Clin N Am. 2011:37:201-217.
8. Reuters V, Teixeira Pde F, Vigário PS, et al. Functional capacity and muscular abnormalities in subclinical hypothyroidism. Am J Med Sci. 2009;338:259-263.
9. Nieman LK, Biller BM, Findling JW, et al. The diagnosis of Cushing’s syndrome: an Endocrine Society clinical practice guideline. J Clin Endocrinol Metab. 2008;93:1526-1540.
10. Holick MF, Binkley NC, Bischoff-Ferrari HA, et al; Endocrine Society. Evaluation, treatment, and prevention of vitamin D deficiency: an Endocrine Society clinical practice guideline. J Clin Endocrinol Metab. 2011;96:1911-1930.
11. Antons KA, Williams CD, Baker SK, et al. Clinical perspectives of statin-induced rhabdomyolysis. Am J Med. 2006;119:400-409.
12. Phillips PS, Haas RH, Bannykh S, et al; Scripps Mercy Clinical Research Center. Statin-associated myopathy with normal creatine kinase levels. Ann Intern Med. 2002;137:581-585.
13. Pereira RM, Freire de Carvalho J. Glucocorticoid-induced myopathy. Joint Bone Spine. 2011;78:41-44.
14. Posada C, García-Cruz A, García-Doval I, et al. Chloroquine-induced myopathy. Lupus. 2011;20:773-774.
15. Uri DS, Biavis M. Colchicine neuromyopathy. J Clin Rheumatol. 1996;2:163-166.
16. Mannix R, Tan ML, Wright R, et al. Acute pediatric rhabdomyolysis: causes and rates of renal failure. Pediatrics. 2006;118:2119-2125.
17. Pozio E. World distribution of Trichinella spp. infections in animals and humans. Vet Parasitol. 2007;149:3-21.
18. Rodolico C, Toscano A, Benvenga S, et al. Myopathy as the persistently isolated symptomatology of primary autoimmune hypothyroidism. Thyroid.1998;8:1033-1038.
19. AACE/AAES Task Force on Primary Hyperparathyroidism. The American Association of Clinical Endocrinologists and The American Association of Endocrine Surgeons position statement on the diagnosis and management of primary hyperparathyroidism. Endocr Pract. 2005;11:49-54.
20. Garber JR, Cobin RH, Gharib H, et al; American Association of Clinical Endocrinologists and American Thyroid Association Taskforce on Hypothyroidism in Adults. Clinical practice guidelines for hypothyroidism in adults: cosponsored by the American Association of Clinical Endocrinologists and the American Thyroid Association. Endocrine Pract. 2012;18:988-1028.
21. Bahn Chair RS, Burch HB, Cooper DS, et al; American Thyroid Association; American Association of Clinical Endocrinologists. Hyperthyroidism and other causes of thyrotoxicosis: management guidelines of the American Thyroid Association and American Association of Clinical Endocrinologists. Thyroid. 2011;21:593-646.
22. Mammen AL, Amato AA. Statin myopathy: a review of recent progress. Curr Opin Rheumatol. 2010;22:644-650.
23. Buettner C, Davis RB, Leveille SG, et al. Prevalence of musculoskeletal pain and statin use. J Gen Intern Med. 2008;23: 1182-1186.
24. Marot A, Morelle J, Chouinard VA, et al. Concomitant use of simvastatin and amiodarone resulting in severe rhabdomyolysis: a case report and review of the literature. Acta Clin Belg. 2011;66:134-136.
25. Peters BS, Winer J, Landon DN, et al. Mitochondrial myopathy associated with chronic zidovudine therapy in AIDS. Q J Med. 1993;86:5-15.
Premature infant has CP: $14.5M verdict
Premature infant has CP: $14.5M verdict
After learning that, 14 years earlier, a 36-year-old woman had undergone an emergency cesarean delivery at 32 weeks’ gestation, her health-care providers planned a cesarean delivery for the new pregnancy. The woman was admitted to the hospital in preterm labor. Three days later, she was discharged, but readmitted twice more over a 2-week period. At each admission, preterm labor was halted using medication and bed rest.
The patient’s water broke and she was admitted to the hospital at 25 weeks’ gestation, about a week after the previous admission. Shortly after admission, the patient asked about a cesarean delivery, but no action was taken. When her ObGyn arrived at the hospital 5 hours later, the patient asked for a cesarean delivery; the ObGyn said he wanted to wait to see how her labor was progressing. After 3 hours, the fetus showed signs of distress, and an emergency cesarean delivery was undertaken. The infant experienced a massive brain hemorrhage, resulting in cerebral palsy (CP). The child has cognitive delays, visual impairment, and additional problems; he will require lifelong care.
PARENTS’ CLAIM The ObGyn and hospital were negligent in discharging the woman from admission for preterm labor. Cesarean delivery should have been performed much earlier due to nonreassuring fetal heart tones. Severe variable decelerations caused cerebral blood flow fluctuations that led to the hemorrhage.
DEFENDANTS’ DEFENSE The child’s prematurity and a severe placental infection led to the injuries. Nothing would have changed the outcome.
VERDICT A $14.5 million Ohio verdict was returned, including $1.5 million for the mother.
_______________
Costs returned afterverdict for the defense
A 65-year-old woman underwent a hysterectomy for treatment of uterine cancer performed by a gynecologic oncologist. Postoperatively, the patient developed an infection. A small-bowel injury was surgically repaired. The patient was hospitalized for 4 months for treatment of sepsis.
PARENTS’ CLAIM The physician was negligent for injuring the patient’s bowel and then failing to identify and repair the injury during surgery.
PHYSICIAN’S DEFENSE There was no negligence. The patient had significant adhesions from prior surgeries. The physician noted minor serosal tears of the bowel, several of which were repaired during surgery. He checked the length of the bowel for tears/perforations several times during the procedure, but found none. The patient had areas of weakness in her bowel, one of which broke down after surgery. The perforation was repaired in a timely manner.
VERDICT A Michigan defense verdict was returned. The physician was awarded $14,535 in costs.
_______________
Colon injury after cystectomy
A 21-year-old woman underwent laparoscopic ovarian cystectomy, performed by her gynecologist, and was discharged the next day. Eight days later, the patient went to the emergency department (ED) with pelvic pain. Testing revealed a perforated colon with peritonitis. She underwent repair by laparotomy, including bowel resection and colostomy, which was reversed several months later. She has not regained regular bowel function, cannot digest food that has not been finely sliced, and constantly uses laxatives.
PARENTS’ CLAIM The colon injury occurred during cystectomy because the gynecologist was negligent in failing to maintain proper anatomical landmarks. The injury should have been recognized at the time of surgery by injecting saline solution into the colon. She had not been informed of the risk of colon injury.
DEFENDANTS’ DEFENSE Colon injury is a known complication of cystectomy. The injury could have occurred after surgery due to a minor nick of the colon that was undetectable during surgery. Proper informed consent was acquired.
VERDICT A $340,000 New York settlement was reached.
_______________
Mother hemorrhages, dies after delivery: $1M settlement
A 19-year-old woman presented at full term to a community hospital. After several hours of labor, an emergency cesarean delivery was performed due to arrested descent.
Fifteen minutes after delivery, the mother exhibited moderate bleeding with decreasing blood pressure and tachycardia. The post-anesthesia care unit nurse assessed the patient’s uterus as “boggy,” and alerted the ObGyn, who immediately reacted by expressing clots from the uterus. He noted that the fundus was firm. He ordered intravenous (IV) oxytocin, but the patient continued to hemorrhage. Fifteen minutes later, the patient’s vital signs worsened. The ObGyn ordered blood products, uterotonics, and an additional IV line for fluid resuscitation. He began to massage the fundus and expressed clots.
When the patient did not stabilize, she was returned to the OR. After attempting to stop the bleeding with O’Leary stitches, the ObGyn performed a hysterectomy. Six hours after surgery, and after transfusion of a total of 12 units of blood, the woman coded multiple times. She died 14 hours after delivery. Cause of death was disseminated intravascular coagulopathy caused by an atonic uterus.
ESTATE’S CLAIM The ObGyn failed to recognize the extent of the postpartum hemorrhage and should have acted more aggressively with resuscitation. He should have returned her to the OR earlier. The ObGyn was negligent in waiting 45 minutes for cross-matched blood rather than using universal donor O-negative blood that was readily available.
PHYSICIAN’S DEFENSE The ObGyn denied negligence and maintained that he had acted properly. He returned the patient to the OR within 90 minutes of first learning of the hemorrhage.
VERDICT A $1 million Virginia settlement was reached.
_______________
Infant born with broken arms, collarbone, facial bones
A 23-year-old woman had gestational diabetes. She is 5’9” tall and weighed 300 lb while pregnant. She went to the hospital in labor.
During delivery, shoulder dystocia was encountered. The ObGyn performed a variety of techniques, including the McRobert’s maneuver. Forceps were eventually used for delivery.
Both of the newborn’s arms were broken, and she had a broken collarbone and facial fractures. The mother also suffered significant vaginal lacerations and required an episiotomy. She continues to complain of bladder and bowel problems.
PARENTS’ CLAIM A vaginal delivery should not have been attempted due to the mother’s gestational diabetes and the risk of having a macrosomic baby. A cesarean delivery should have been performed. The ObGyn did not use the proper techniques when delivering the child after shoulder dystocia was encountered.
PHYSICIAN’S DEFENSE The ObGyn denied negligence. He claimed that the baby recovered well from her injuries. The mother underwent surgery and now has excellent bladder and bowel control.
VERDICT A confidential Louisiana settlement was reached with the hospital before trial. A defense verdict was returned for the ObGyn.
_______________
Protein found in urine at 39 weeks’ gestation: mother and child die
At 39 weeks' gestation, a woman saw her ObGyn for a prenatal visit. During the examination, the ObGyn found high levels of protein in the woman’s urine, an accumulation of fluid in her ankles, and the highest blood pressure (BP) reading of the woman’s pregnancy. However, because the BP reading was lower than that required to diagnose preeclampsia, the ObGyn sent the patient home and scheduled the next prenatal visit for the following week. The woman and her unborn child died 5 days later.
ESTATE’S CLAIM The ObGyn was negligent in failing to order a urine study and more closely monitor the mother’s symptoms when signs of preeclampsia were evident at 39 weeks’ gestation. Delivery of the child would have resolved the problem and saved both lives.
PHYSICIAN’S DEFENSE The case was settled during the trial.
VERDICT A $3 million Illinois settlement was reached.
_______________
Baby dies from group B strep
A 16-year-old woman planned delivery at a local hospital. Her ObGyn’s practice regularly sends the hospital its patients’ prenatal records, starting at 25 weeks’ gestation. At 33 weeks, the ObGyn took a vaginal culture to test for group B Streptococcus (GBS) bacteria. The laboratory reported positive GBS results to a computer in the ObGyn’s office, but the results were not entered into the patient’s chart.
The mother went to the ED in labor a week later; she was evaluated and discharged. Several days later, she returned to the ED, but was again discharged. She returned the next day, now in gestational week 36. An on-call ObGyn admitted her. A labor and delivery nurse claimed that the ObGyn’s office reported that the mother was GBS negative, so the nurse placed a negative sign in the prenatal record in the chart. When the patient’s ObGyn arrived at the hospital, he noticed the negative sign in the chart.
At birth, the baby’s Apgar scores were 7 at 1 minute and 7 at 5 minutes. She appeared limp and was grunting. A pediatrician diagnosed transient respiratory problems related to prematurity. The baby continued to deteriorate; antibiotics were ordered 7 hours after birth. After the child was transported to another facility, she died. The cause of death was GBS sepsis and pneumonia.
PARENTS’ CLAIM The ObGyn was negligent in failing to properly and timely note the positive GBS test result in the mother’s chart. The ObGyn’s office staff was negligent in miscommunicating the GBS status to the nurse.
DEFENDANTS’ DEFENSE The ObGyn usually noted laboratory results at the next prenatal visit, but the mother gave birth before that occurred. The on-call ObGyn failed to give antibiotics when the mother presented in preterm labor with unknown GBS status. The hospital did not have a protocol that required the on-call ObGyn to prescribe prophylactic antibiotics in this context. The nurse was negligent for failing to verify the oral telephone report of GBS-negative status with a written or faxed laboratory report.
The ObGyn surmised that the infection had occurred in utero, not during birth; antibiotics would not have changed the outcome.
VERDICT The parents settled with the hospital for a confidential amount. An Arizona defense verdict was returned for the ObGyn.
_______________
Child has quadraparetic CP after oxytocin-augmented delivery
A pregnant woman was hospitalized for 23-hour observation with blood work and obstetric ultrasonography. The admitting nurse noted that the patient was having mild contractions and that fetal heart tones were 130 bpm with moderate variability. The mother’s cervix was dilated to 2.5 cm, 70% effaced, at –1 station, with intact and bulging membranes and normal maternal vital signs. The ObGyn ordered intravenous ampicillin and sent the mother to labor and delivery. He prescribed oxytocin (6 mU/min), but, after its initiation, oxytocin was discontinued for almost 2 hours. When the mother had five contractions in 10 minutes, oxytocin was restarted at 8 mU/min. The oxytocin dosage was later increased to 10 mU/min, and then to 12 mU/min.
When shoulder dystocia was encountered, various maneuvers were performed. The baby was delivered using vacuum extraction. The newborn was immediately sent to the neonatal intensive care unit (NICU) with a suspected humerus fracture and poor respiration. Mechanical ventilation and treatment for hypoperfusion were initiated. She had persistently low Apgar scores, intracranial hemorrhaging, seizures, severe metabolic acidosis, and hypoxic ischemic encephalopathy. She has quadraparetic cerebral palsy with related disabilities.
PARENTS’ CLAIM The ObGyn and hospital were negligent in the treatment of the mother during labor and delivery, causing the child to be born with serious injuries.
DEFENDANTS’ DEFENSE The case was settled during the trial.
VERDICT A $4,250,000 Texas settlement was reached, including $75,000 for the parents, and the remainder placed into a trust for the child.
These cases were selected by the editors of OBG Management from Medical Malpractice Verdicts, Settlements & Experts, with permission of the editor, Lewis Laska (www.verdictslaska.com). The information available to the editors about the cases presented here is sometimes incomplete. Moreover, the cases may or may not have merit. Nevertheless, these cases represent the types of clinical situations that typically result in litigation and are meant to illustrate nationwide variation in jury verdicts and awards.
Premature infant has CP: $14.5M verdict
After learning that, 14 years earlier, a 36-year-old woman had undergone an emergency cesarean delivery at 32 weeks’ gestation, her health-care providers planned a cesarean delivery for the new pregnancy. The woman was admitted to the hospital in preterm labor. Three days later, she was discharged, but readmitted twice more over a 2-week period. At each admission, preterm labor was halted using medication and bed rest.
The patient’s water broke and she was admitted to the hospital at 25 weeks’ gestation, about a week after the previous admission. Shortly after admission, the patient asked about a cesarean delivery, but no action was taken. When her ObGyn arrived at the hospital 5 hours later, the patient asked for a cesarean delivery; the ObGyn said he wanted to wait to see how her labor was progressing. After 3 hours, the fetus showed signs of distress, and an emergency cesarean delivery was undertaken. The infant experienced a massive brain hemorrhage, resulting in cerebral palsy (CP). The child has cognitive delays, visual impairment, and additional problems; he will require lifelong care.
PARENTS’ CLAIM The ObGyn and hospital were negligent in discharging the woman from admission for preterm labor. Cesarean delivery should have been performed much earlier due to nonreassuring fetal heart tones. Severe variable decelerations caused cerebral blood flow fluctuations that led to the hemorrhage.
DEFENDANTS’ DEFENSE The child’s prematurity and a severe placental infection led to the injuries. Nothing would have changed the outcome.
VERDICT A $14.5 million Ohio verdict was returned, including $1.5 million for the mother.
_______________
Costs returned afterverdict for the defense
A 65-year-old woman underwent a hysterectomy for treatment of uterine cancer performed by a gynecologic oncologist. Postoperatively, the patient developed an infection. A small-bowel injury was surgically repaired. The patient was hospitalized for 4 months for treatment of sepsis.
PARENTS’ CLAIM The physician was negligent for injuring the patient’s bowel and then failing to identify and repair the injury during surgery.
PHYSICIAN’S DEFENSE There was no negligence. The patient had significant adhesions from prior surgeries. The physician noted minor serosal tears of the bowel, several of which were repaired during surgery. He checked the length of the bowel for tears/perforations several times during the procedure, but found none. The patient had areas of weakness in her bowel, one of which broke down after surgery. The perforation was repaired in a timely manner.
VERDICT A Michigan defense verdict was returned. The physician was awarded $14,535 in costs.
_______________
Colon injury after cystectomy
A 21-year-old woman underwent laparoscopic ovarian cystectomy, performed by her gynecologist, and was discharged the next day. Eight days later, the patient went to the emergency department (ED) with pelvic pain. Testing revealed a perforated colon with peritonitis. She underwent repair by laparotomy, including bowel resection and colostomy, which was reversed several months later. She has not regained regular bowel function, cannot digest food that has not been finely sliced, and constantly uses laxatives.
PARENTS’ CLAIM The colon injury occurred during cystectomy because the gynecologist was negligent in failing to maintain proper anatomical landmarks. The injury should have been recognized at the time of surgery by injecting saline solution into the colon. She had not been informed of the risk of colon injury.
DEFENDANTS’ DEFENSE Colon injury is a known complication of cystectomy. The injury could have occurred after surgery due to a minor nick of the colon that was undetectable during surgery. Proper informed consent was acquired.
VERDICT A $340,000 New York settlement was reached.
_______________
Mother hemorrhages, dies after delivery: $1M settlement
A 19-year-old woman presented at full term to a community hospital. After several hours of labor, an emergency cesarean delivery was performed due to arrested descent.
Fifteen minutes after delivery, the mother exhibited moderate bleeding with decreasing blood pressure and tachycardia. The post-anesthesia care unit nurse assessed the patient’s uterus as “boggy,” and alerted the ObGyn, who immediately reacted by expressing clots from the uterus. He noted that the fundus was firm. He ordered intravenous (IV) oxytocin, but the patient continued to hemorrhage. Fifteen minutes later, the patient’s vital signs worsened. The ObGyn ordered blood products, uterotonics, and an additional IV line for fluid resuscitation. He began to massage the fundus and expressed clots.
When the patient did not stabilize, she was returned to the OR. After attempting to stop the bleeding with O’Leary stitches, the ObGyn performed a hysterectomy. Six hours after surgery, and after transfusion of a total of 12 units of blood, the woman coded multiple times. She died 14 hours after delivery. Cause of death was disseminated intravascular coagulopathy caused by an atonic uterus.
ESTATE’S CLAIM The ObGyn failed to recognize the extent of the postpartum hemorrhage and should have acted more aggressively with resuscitation. He should have returned her to the OR earlier. The ObGyn was negligent in waiting 45 minutes for cross-matched blood rather than using universal donor O-negative blood that was readily available.
PHYSICIAN’S DEFENSE The ObGyn denied negligence and maintained that he had acted properly. He returned the patient to the OR within 90 minutes of first learning of the hemorrhage.
VERDICT A $1 million Virginia settlement was reached.
_______________
Infant born with broken arms, collarbone, facial bones
A 23-year-old woman had gestational diabetes. She is 5’9” tall and weighed 300 lb while pregnant. She went to the hospital in labor.
During delivery, shoulder dystocia was encountered. The ObGyn performed a variety of techniques, including the McRobert’s maneuver. Forceps were eventually used for delivery.
Both of the newborn’s arms were broken, and she had a broken collarbone and facial fractures. The mother also suffered significant vaginal lacerations and required an episiotomy. She continues to complain of bladder and bowel problems.
PARENTS’ CLAIM A vaginal delivery should not have been attempted due to the mother’s gestational diabetes and the risk of having a macrosomic baby. A cesarean delivery should have been performed. The ObGyn did not use the proper techniques when delivering the child after shoulder dystocia was encountered.
PHYSICIAN’S DEFENSE The ObGyn denied negligence. He claimed that the baby recovered well from her injuries. The mother underwent surgery and now has excellent bladder and bowel control.
VERDICT A confidential Louisiana settlement was reached with the hospital before trial. A defense verdict was returned for the ObGyn.
_______________
Protein found in urine at 39 weeks’ gestation: mother and child die
At 39 weeks' gestation, a woman saw her ObGyn for a prenatal visit. During the examination, the ObGyn found high levels of protein in the woman’s urine, an accumulation of fluid in her ankles, and the highest blood pressure (BP) reading of the woman’s pregnancy. However, because the BP reading was lower than that required to diagnose preeclampsia, the ObGyn sent the patient home and scheduled the next prenatal visit for the following week. The woman and her unborn child died 5 days later.
ESTATE’S CLAIM The ObGyn was negligent in failing to order a urine study and more closely monitor the mother’s symptoms when signs of preeclampsia were evident at 39 weeks’ gestation. Delivery of the child would have resolved the problem and saved both lives.
PHYSICIAN’S DEFENSE The case was settled during the trial.
VERDICT A $3 million Illinois settlement was reached.
_______________
Baby dies from group B strep
A 16-year-old woman planned delivery at a local hospital. Her ObGyn’s practice regularly sends the hospital its patients’ prenatal records, starting at 25 weeks’ gestation. At 33 weeks, the ObGyn took a vaginal culture to test for group B Streptococcus (GBS) bacteria. The laboratory reported positive GBS results to a computer in the ObGyn’s office, but the results were not entered into the patient’s chart.
The mother went to the ED in labor a week later; she was evaluated and discharged. Several days later, she returned to the ED, but was again discharged. She returned the next day, now in gestational week 36. An on-call ObGyn admitted her. A labor and delivery nurse claimed that the ObGyn’s office reported that the mother was GBS negative, so the nurse placed a negative sign in the prenatal record in the chart. When the patient’s ObGyn arrived at the hospital, he noticed the negative sign in the chart.
At birth, the baby’s Apgar scores were 7 at 1 minute and 7 at 5 minutes. She appeared limp and was grunting. A pediatrician diagnosed transient respiratory problems related to prematurity. The baby continued to deteriorate; antibiotics were ordered 7 hours after birth. After the child was transported to another facility, she died. The cause of death was GBS sepsis and pneumonia.
PARENTS’ CLAIM The ObGyn was negligent in failing to properly and timely note the positive GBS test result in the mother’s chart. The ObGyn’s office staff was negligent in miscommunicating the GBS status to the nurse.
DEFENDANTS’ DEFENSE The ObGyn usually noted laboratory results at the next prenatal visit, but the mother gave birth before that occurred. The on-call ObGyn failed to give antibiotics when the mother presented in preterm labor with unknown GBS status. The hospital did not have a protocol that required the on-call ObGyn to prescribe prophylactic antibiotics in this context. The nurse was negligent for failing to verify the oral telephone report of GBS-negative status with a written or faxed laboratory report.
The ObGyn surmised that the infection had occurred in utero, not during birth; antibiotics would not have changed the outcome.
VERDICT The parents settled with the hospital for a confidential amount. An Arizona defense verdict was returned for the ObGyn.
_______________
Child has quadraparetic CP after oxytocin-augmented delivery
A pregnant woman was hospitalized for 23-hour observation with blood work and obstetric ultrasonography. The admitting nurse noted that the patient was having mild contractions and that fetal heart tones were 130 bpm with moderate variability. The mother’s cervix was dilated to 2.5 cm, 70% effaced, at –1 station, with intact and bulging membranes and normal maternal vital signs. The ObGyn ordered intravenous ampicillin and sent the mother to labor and delivery. He prescribed oxytocin (6 mU/min), but, after its initiation, oxytocin was discontinued for almost 2 hours. When the mother had five contractions in 10 minutes, oxytocin was restarted at 8 mU/min. The oxytocin dosage was later increased to 10 mU/min, and then to 12 mU/min.
When shoulder dystocia was encountered, various maneuvers were performed. The baby was delivered using vacuum extraction. The newborn was immediately sent to the neonatal intensive care unit (NICU) with a suspected humerus fracture and poor respiration. Mechanical ventilation and treatment for hypoperfusion were initiated. She had persistently low Apgar scores, intracranial hemorrhaging, seizures, severe metabolic acidosis, and hypoxic ischemic encephalopathy. She has quadraparetic cerebral palsy with related disabilities.
PARENTS’ CLAIM The ObGyn and hospital were negligent in the treatment of the mother during labor and delivery, causing the child to be born with serious injuries.
DEFENDANTS’ DEFENSE The case was settled during the trial.
VERDICT A $4,250,000 Texas settlement was reached, including $75,000 for the parents, and the remainder placed into a trust for the child.
These cases were selected by the editors of OBG Management from Medical Malpractice Verdicts, Settlements & Experts, with permission of the editor, Lewis Laska (www.verdictslaska.com). The information available to the editors about the cases presented here is sometimes incomplete. Moreover, the cases may or may not have merit. Nevertheless, these cases represent the types of clinical situations that typically result in litigation and are meant to illustrate nationwide variation in jury verdicts and awards.
Premature infant has CP: $14.5M verdict
After learning that, 14 years earlier, a 36-year-old woman had undergone an emergency cesarean delivery at 32 weeks’ gestation, her health-care providers planned a cesarean delivery for the new pregnancy. The woman was admitted to the hospital in preterm labor. Three days later, she was discharged, but readmitted twice more over a 2-week period. At each admission, preterm labor was halted using medication and bed rest.
The patient’s water broke and she was admitted to the hospital at 25 weeks’ gestation, about a week after the previous admission. Shortly after admission, the patient asked about a cesarean delivery, but no action was taken. When her ObGyn arrived at the hospital 5 hours later, the patient asked for a cesarean delivery; the ObGyn said he wanted to wait to see how her labor was progressing. After 3 hours, the fetus showed signs of distress, and an emergency cesarean delivery was undertaken. The infant experienced a massive brain hemorrhage, resulting in cerebral palsy (CP). The child has cognitive delays, visual impairment, and additional problems; he will require lifelong care.
PARENTS’ CLAIM The ObGyn and hospital were negligent in discharging the woman from admission for preterm labor. Cesarean delivery should have been performed much earlier due to nonreassuring fetal heart tones. Severe variable decelerations caused cerebral blood flow fluctuations that led to the hemorrhage.
DEFENDANTS’ DEFENSE The child’s prematurity and a severe placental infection led to the injuries. Nothing would have changed the outcome.
VERDICT A $14.5 million Ohio verdict was returned, including $1.5 million for the mother.
_______________
Costs returned afterverdict for the defense
A 65-year-old woman underwent a hysterectomy for treatment of uterine cancer performed by a gynecologic oncologist. Postoperatively, the patient developed an infection. A small-bowel injury was surgically repaired. The patient was hospitalized for 4 months for treatment of sepsis.
PARENTS’ CLAIM The physician was negligent for injuring the patient’s bowel and then failing to identify and repair the injury during surgery.
PHYSICIAN’S DEFENSE There was no negligence. The patient had significant adhesions from prior surgeries. The physician noted minor serosal tears of the bowel, several of which were repaired during surgery. He checked the length of the bowel for tears/perforations several times during the procedure, but found none. The patient had areas of weakness in her bowel, one of which broke down after surgery. The perforation was repaired in a timely manner.
VERDICT A Michigan defense verdict was returned. The physician was awarded $14,535 in costs.
_______________
Colon injury after cystectomy
A 21-year-old woman underwent laparoscopic ovarian cystectomy, performed by her gynecologist, and was discharged the next day. Eight days later, the patient went to the emergency department (ED) with pelvic pain. Testing revealed a perforated colon with peritonitis. She underwent repair by laparotomy, including bowel resection and colostomy, which was reversed several months later. She has not regained regular bowel function, cannot digest food that has not been finely sliced, and constantly uses laxatives.
PARENTS’ CLAIM The colon injury occurred during cystectomy because the gynecologist was negligent in failing to maintain proper anatomical landmarks. The injury should have been recognized at the time of surgery by injecting saline solution into the colon. She had not been informed of the risk of colon injury.
DEFENDANTS’ DEFENSE Colon injury is a known complication of cystectomy. The injury could have occurred after surgery due to a minor nick of the colon that was undetectable during surgery. Proper informed consent was acquired.
VERDICT A $340,000 New York settlement was reached.
_______________
Mother hemorrhages, dies after delivery: $1M settlement
A 19-year-old woman presented at full term to a community hospital. After several hours of labor, an emergency cesarean delivery was performed due to arrested descent.
Fifteen minutes after delivery, the mother exhibited moderate bleeding with decreasing blood pressure and tachycardia. The post-anesthesia care unit nurse assessed the patient’s uterus as “boggy,” and alerted the ObGyn, who immediately reacted by expressing clots from the uterus. He noted that the fundus was firm. He ordered intravenous (IV) oxytocin, but the patient continued to hemorrhage. Fifteen minutes later, the patient’s vital signs worsened. The ObGyn ordered blood products, uterotonics, and an additional IV line for fluid resuscitation. He began to massage the fundus and expressed clots.
When the patient did not stabilize, she was returned to the OR. After attempting to stop the bleeding with O’Leary stitches, the ObGyn performed a hysterectomy. Six hours after surgery, and after transfusion of a total of 12 units of blood, the woman coded multiple times. She died 14 hours after delivery. Cause of death was disseminated intravascular coagulopathy caused by an atonic uterus.
ESTATE’S CLAIM The ObGyn failed to recognize the extent of the postpartum hemorrhage and should have acted more aggressively with resuscitation. He should have returned her to the OR earlier. The ObGyn was negligent in waiting 45 minutes for cross-matched blood rather than using universal donor O-negative blood that was readily available.
PHYSICIAN’S DEFENSE The ObGyn denied negligence and maintained that he had acted properly. He returned the patient to the OR within 90 minutes of first learning of the hemorrhage.
VERDICT A $1 million Virginia settlement was reached.
_______________
Infant born with broken arms, collarbone, facial bones
A 23-year-old woman had gestational diabetes. She is 5’9” tall and weighed 300 lb while pregnant. She went to the hospital in labor.
During delivery, shoulder dystocia was encountered. The ObGyn performed a variety of techniques, including the McRobert’s maneuver. Forceps were eventually used for delivery.
Both of the newborn’s arms were broken, and she had a broken collarbone and facial fractures. The mother also suffered significant vaginal lacerations and required an episiotomy. She continues to complain of bladder and bowel problems.
PARENTS’ CLAIM A vaginal delivery should not have been attempted due to the mother’s gestational diabetes and the risk of having a macrosomic baby. A cesarean delivery should have been performed. The ObGyn did not use the proper techniques when delivering the child after shoulder dystocia was encountered.
PHYSICIAN’S DEFENSE The ObGyn denied negligence. He claimed that the baby recovered well from her injuries. The mother underwent surgery and now has excellent bladder and bowel control.
VERDICT A confidential Louisiana settlement was reached with the hospital before trial. A defense verdict was returned for the ObGyn.
_______________
Protein found in urine at 39 weeks’ gestation: mother and child die
At 39 weeks' gestation, a woman saw her ObGyn for a prenatal visit. During the examination, the ObGyn found high levels of protein in the woman’s urine, an accumulation of fluid in her ankles, and the highest blood pressure (BP) reading of the woman’s pregnancy. However, because the BP reading was lower than that required to diagnose preeclampsia, the ObGyn sent the patient home and scheduled the next prenatal visit for the following week. The woman and her unborn child died 5 days later.
ESTATE’S CLAIM The ObGyn was negligent in failing to order a urine study and more closely monitor the mother’s symptoms when signs of preeclampsia were evident at 39 weeks’ gestation. Delivery of the child would have resolved the problem and saved both lives.
PHYSICIAN’S DEFENSE The case was settled during the trial.
VERDICT A $3 million Illinois settlement was reached.
_______________
Baby dies from group B strep
A 16-year-old woman planned delivery at a local hospital. Her ObGyn’s practice regularly sends the hospital its patients’ prenatal records, starting at 25 weeks’ gestation. At 33 weeks, the ObGyn took a vaginal culture to test for group B Streptococcus (GBS) bacteria. The laboratory reported positive GBS results to a computer in the ObGyn’s office, but the results were not entered into the patient’s chart.
The mother went to the ED in labor a week later; she was evaluated and discharged. Several days later, she returned to the ED, but was again discharged. She returned the next day, now in gestational week 36. An on-call ObGyn admitted her. A labor and delivery nurse claimed that the ObGyn’s office reported that the mother was GBS negative, so the nurse placed a negative sign in the prenatal record in the chart. When the patient’s ObGyn arrived at the hospital, he noticed the negative sign in the chart.
At birth, the baby’s Apgar scores were 7 at 1 minute and 7 at 5 minutes. She appeared limp and was grunting. A pediatrician diagnosed transient respiratory problems related to prematurity. The baby continued to deteriorate; antibiotics were ordered 7 hours after birth. After the child was transported to another facility, she died. The cause of death was GBS sepsis and pneumonia.
PARENTS’ CLAIM The ObGyn was negligent in failing to properly and timely note the positive GBS test result in the mother’s chart. The ObGyn’s office staff was negligent in miscommunicating the GBS status to the nurse.
DEFENDANTS’ DEFENSE The ObGyn usually noted laboratory results at the next prenatal visit, but the mother gave birth before that occurred. The on-call ObGyn failed to give antibiotics when the mother presented in preterm labor with unknown GBS status. The hospital did not have a protocol that required the on-call ObGyn to prescribe prophylactic antibiotics in this context. The nurse was negligent for failing to verify the oral telephone report of GBS-negative status with a written or faxed laboratory report.
The ObGyn surmised that the infection had occurred in utero, not during birth; antibiotics would not have changed the outcome.
VERDICT The parents settled with the hospital for a confidential amount. An Arizona defense verdict was returned for the ObGyn.
_______________
Child has quadraparetic CP after oxytocin-augmented delivery
A pregnant woman was hospitalized for 23-hour observation with blood work and obstetric ultrasonography. The admitting nurse noted that the patient was having mild contractions and that fetal heart tones were 130 bpm with moderate variability. The mother’s cervix was dilated to 2.5 cm, 70% effaced, at –1 station, with intact and bulging membranes and normal maternal vital signs. The ObGyn ordered intravenous ampicillin and sent the mother to labor and delivery. He prescribed oxytocin (6 mU/min), but, after its initiation, oxytocin was discontinued for almost 2 hours. When the mother had five contractions in 10 minutes, oxytocin was restarted at 8 mU/min. The oxytocin dosage was later increased to 10 mU/min, and then to 12 mU/min.
When shoulder dystocia was encountered, various maneuvers were performed. The baby was delivered using vacuum extraction. The newborn was immediately sent to the neonatal intensive care unit (NICU) with a suspected humerus fracture and poor respiration. Mechanical ventilation and treatment for hypoperfusion were initiated. She had persistently low Apgar scores, intracranial hemorrhaging, seizures, severe metabolic acidosis, and hypoxic ischemic encephalopathy. She has quadraparetic cerebral palsy with related disabilities.
PARENTS’ CLAIM The ObGyn and hospital were negligent in the treatment of the mother during labor and delivery, causing the child to be born with serious injuries.
DEFENDANTS’ DEFENSE The case was settled during the trial.
VERDICT A $4,250,000 Texas settlement was reached, including $75,000 for the parents, and the remainder placed into a trust for the child.
These cases were selected by the editors of OBG Management from Medical Malpractice Verdicts, Settlements & Experts, with permission of the editor, Lewis Laska (www.verdictslaska.com). The information available to the editors about the cases presented here is sometimes incomplete. Moreover, the cases may or may not have merit. Nevertheless, these cases represent the types of clinical situations that typically result in litigation and are meant to illustrate nationwide variation in jury verdicts and awards.
EMA grants product orphan status for AML
The European Medicines Agency (EMA) has granted orphan status to Atir, a product consisting of T-cell-depleted donor immune cells, for the treatment of acute myeloid leukemia (AML).
The EMA and the US Food and Drug Administration previously granted Atir orphan status for the prevention of acute graft-vs-host-disease (GVHD) following hematopoietic stem cell transplant (HSCT).
The EMA’s orphan designation provides incentives to support drug development. This includes fee reductions and a 10-year period of market exclusivity in the European Union after product approval.
About Atir
Atir consists of donor immune cells from which the alloreactive T-cells that would otherwise attack the patient’s body have been selectively eliminated.
The product is produced using a molecule known as TH9402 to selectively remove those T cells from the donor graft, while preserving other immune cells. To activate patient-reactive T cells, the graft is mixed (ex vivo) with patient cells.
Then, TH9402 is added. As this phototoxic compound selectively accumulates in activated T cells, the cells can be eliminated by exposing the cell mixture to light of a specific wavelength. The resulting Atir product can be frozen and stored and is infused into the patient in a scheduled procedure.
Trial data
Researchers said Atir proved safe and effective in a phase 1/2 study in which high-risk leukemia patients with very poor prognosis were treated with escalating doses of Atir after a haploidentical HSCT.
The overall survival of 19 patients who received an optimal dose of Atir was 78% at 1 year and 67% at 5 years, rates that compare favorably to outcomes of HSCTs from fully matched donors. The data also suggest that immune cells responsible for the graft-vs-leukemia effect are retained in Atir.
Five-year follow-up data show that none of the 19 patients developed acute grade 3/4 GVHD, compared to an incidence of 30% in matched unrelated HSCTs. In the 9 patients who received an optimal dose of Atir, there was no transplant-related mortality.
Researchers are currently testing Atir in a phase 2 study of patients with AML, acute lymphoblastic leukemia, and myelodysplastic syndrome, to corroborate and extend the safety and efficacy results from the phase 1/2 study. Data from this trial are expected in the second half of 2014.
Atir is under development by Kiadis Pharma. For more information, visit the company’s website.
The European Medicines Agency (EMA) has granted orphan status to Atir, a product consisting of T-cell-depleted donor immune cells, for the treatment of acute myeloid leukemia (AML).
The EMA and the US Food and Drug Administration previously granted Atir orphan status for the prevention of acute graft-vs-host-disease (GVHD) following hematopoietic stem cell transplant (HSCT).
The EMA’s orphan designation provides incentives to support drug development. This includes fee reductions and a 10-year period of market exclusivity in the European Union after product approval.
About Atir
Atir consists of donor immune cells from which the alloreactive T-cells that would otherwise attack the patient’s body have been selectively eliminated.
The product is produced using a molecule known as TH9402 to selectively remove those T cells from the donor graft, while preserving other immune cells. To activate patient-reactive T cells, the graft is mixed (ex vivo) with patient cells.
Then, TH9402 is added. As this phototoxic compound selectively accumulates in activated T cells, the cells can be eliminated by exposing the cell mixture to light of a specific wavelength. The resulting Atir product can be frozen and stored and is infused into the patient in a scheduled procedure.
Trial data
Researchers said Atir proved safe and effective in a phase 1/2 study in which high-risk leukemia patients with very poor prognosis were treated with escalating doses of Atir after a haploidentical HSCT.
The overall survival of 19 patients who received an optimal dose of Atir was 78% at 1 year and 67% at 5 years, rates that compare favorably to outcomes of HSCTs from fully matched donors. The data also suggest that immune cells responsible for the graft-vs-leukemia effect are retained in Atir.
Five-year follow-up data show that none of the 19 patients developed acute grade 3/4 GVHD, compared to an incidence of 30% in matched unrelated HSCTs. In the 9 patients who received an optimal dose of Atir, there was no transplant-related mortality.
Researchers are currently testing Atir in a phase 2 study of patients with AML, acute lymphoblastic leukemia, and myelodysplastic syndrome, to corroborate and extend the safety and efficacy results from the phase 1/2 study. Data from this trial are expected in the second half of 2014.
Atir is under development by Kiadis Pharma. For more information, visit the company’s website.
The European Medicines Agency (EMA) has granted orphan status to Atir, a product consisting of T-cell-depleted donor immune cells, for the treatment of acute myeloid leukemia (AML).
The EMA and the US Food and Drug Administration previously granted Atir orphan status for the prevention of acute graft-vs-host-disease (GVHD) following hematopoietic stem cell transplant (HSCT).
The EMA’s orphan designation provides incentives to support drug development. This includes fee reductions and a 10-year period of market exclusivity in the European Union after product approval.
About Atir
Atir consists of donor immune cells from which the alloreactive T-cells that would otherwise attack the patient’s body have been selectively eliminated.
The product is produced using a molecule known as TH9402 to selectively remove those T cells from the donor graft, while preserving other immune cells. To activate patient-reactive T cells, the graft is mixed (ex vivo) with patient cells.
Then, TH9402 is added. As this phototoxic compound selectively accumulates in activated T cells, the cells can be eliminated by exposing the cell mixture to light of a specific wavelength. The resulting Atir product can be frozen and stored and is infused into the patient in a scheduled procedure.
Trial data
Researchers said Atir proved safe and effective in a phase 1/2 study in which high-risk leukemia patients with very poor prognosis were treated with escalating doses of Atir after a haploidentical HSCT.
The overall survival of 19 patients who received an optimal dose of Atir was 78% at 1 year and 67% at 5 years, rates that compare favorably to outcomes of HSCTs from fully matched donors. The data also suggest that immune cells responsible for the graft-vs-leukemia effect are retained in Atir.
Five-year follow-up data show that none of the 19 patients developed acute grade 3/4 GVHD, compared to an incidence of 30% in matched unrelated HSCTs. In the 9 patients who received an optimal dose of Atir, there was no transplant-related mortality.
Researchers are currently testing Atir in a phase 2 study of patients with AML, acute lymphoblastic leukemia, and myelodysplastic syndrome, to corroborate and extend the safety and efficacy results from the phase 1/2 study. Data from this trial are expected in the second half of 2014.
Atir is under development by Kiadis Pharma. For more information, visit the company’s website.
Topical steroid might improve mucosal integrity in eosinophilic esophagitis
Topical steroid therapy improved some indicators of mucosal integrity in patients with eosinophilic esophagitis, but proton pump inhibitor therapy did not, according to two studies reported in the November issue of Clinical Gastroenterology and Hepatology.
The first study found that topical fluticasone therapy at a dose of 880 mcg twice daily for 2 months helped correct esophageal spongiosis, or dilated intercellular space, in patients with eosinophilic esophagitis (EoE). Spongiosis scores for treated patients were significantly lower than for untreated patients (0.4 vs. 1.3; P = .016), said Dr. David Katzka at the Mayo Clinic in Rochester, Minn. and his associates (Clin. Gastroenterol. Hepatol. 2014 [doi:10.1016/j.cgh.2014.02.039]).
In the study, histologic analyses also showed that improved spongiosis scores in treated patients correlated with increased density of two tight junction proteins, filaggrin (P = .001) and zonula occludens-3 (P = .016), said the investigators. These proteins might help regulate antigenic penetration of the esophageal mucosa and also could permit migration of white blood cells, they said. “Loss of tight junction regulators and dilation of intercellular spaces appear to be involved in the pathophysiology of EoE and could be targets for treatment,” the researchers concluded. But they also noted that their study did not examine the same patients before and after steroid therapy and did not look at desmosomes, intercellular junctions that past research has suggested might be affected in EoE.
For the second study, Dr. Bram van Rhijn and his associates at the Academic Medical Center in the Netherlands compared endoscopies of 16 patients with dysphagia and suspected (unconfirmed) EoE with 11 controls, both at baseline and after 8 weeks of high-dose esomeprazole treatment. Esophageal mucosal integrity was “severely impaired” in patients with confirmed EoE and in those with proton pump inhibitor–responsive eosinophilia (PPRE), the researchers said (Clin. Gasteroenterol. Hepatol. 2014 [doi:10.1016/j.cgh.2014.02.037]).
In both forms of disease, molecules as large as 40,000 daltons were able to pass through the compromised esophageal mucosa, Dr. Bram van Rhijn and his associates reported. “This size is similar to the size of most plant and animal food allergens to which EoE patients are sensitized,” they added. Esophageal permeability might increase the rate of immune exposure to allergens, thereby mediating EoE and PPRE, they said.
On mucosal functional tests, both EoE and PPRE were associated with reduced transepithelial electrical resistance and lower electrical tissue impedance, most notably in patients with EoE (P less than .001 for both, compared with controls), the investigators reported. Proton pump inhibitor treatment partially reversed these changes in patients with PPRE but showed no effect for patients with EoE, they said. This finding suggests that acid reflux might play a role in PPRE, but not in EOE, they concluded.
Dr. Katzka and his associates disclosed no funding sources and reported having no conflicts of interest. Dr. Rhijn and his associates were supported by the Netherlands Organization for Scientific Research. Two of Dr. Rhijn’s coauthors reported financial relationships with AstraZeneca, Endostim, Medical Measurement Systems, Shire, and GlaxoSmithKline.
In the past year, the topic of mucosal integrity in eosinophilic esophagitis has garnered growing attention. Epithelial permeability defects have been described in the pathogenesis of GI disorders, including inflammatory bowel disease and celiac sprue, as well as allergic disorders such as atopic dermatitis. In EoE, both experimental as well as clinical studies have shown an eosinophil-predominant inflammatory response to specific antigens, particularly common food allergens. Increased permeability may predispose genetically susceptible individuals to swallowed allergen penetration through the esophageal epithelium. Beneath the epithelial barrier, antigens have access to antigen presenting cells, including dendritic cells, leading to both allergic sensitization and perpetuation of the TH-2 chronic inflammatory response.
|
| Dr. Ikuo Hirano |
The article by Dr. Katzka and his colleagues supports the concept of epithelial barrier defects in EoE through the demonstration of reduced immunohistochemical expression of filaggrin, zonula occludens-3, and claudin-1, important tight junction proteins. Expression was increased in EoE patients treated with topical steroids. Similarly, the study by Dr. van Rhijn and his associates identified impaired mucosal integrity in EoE by a variety of techniques that included electron microscopic demonstration of dilated intercellular spaces, electrical tissue impedance as an in vivo biomarker, and in vitro transepithelial molecular flux in an Ussing chamber. Furthermore, they found that proton pump inhibitor therapy partially restored mucosal permeability defects to a greater degree in patients with PPI-responsive esophageal eosinophilia, compared with patients with EoE. These two studies substantiate studies from the Cincinnati group that previously identified reduced mRNA expression of filaggrin in esophageal mucosal biopsies as well as reduced expression of the intercellular adhesion molecule, desmoglein 1.
In spite of these novel data, the exact role of altered esophageal epithelial permeability in the pathogenesis of EoE is yet unclear. The reversibility of the defect with medical therapy argues against defective cell junction proteins as an intrinsic abnormality. Furthermore, the location of antigen presentation in EoE may occur through other routes such as the small intestine, nasal epithelium, or skin. In the meantime, these studies provide an important advance in our understanding of EoE and open the door to novel therapeutic approaches.
Dr. Ikuo Hirano, AGAF, is professor of medicine at Northwestern University, Chicago. He reported no conflicts of interest.
In the past year, the topic of mucosal integrity in eosinophilic esophagitis has garnered growing attention. Epithelial permeability defects have been described in the pathogenesis of GI disorders, including inflammatory bowel disease and celiac sprue, as well as allergic disorders such as atopic dermatitis. In EoE, both experimental as well as clinical studies have shown an eosinophil-predominant inflammatory response to specific antigens, particularly common food allergens. Increased permeability may predispose genetically susceptible individuals to swallowed allergen penetration through the esophageal epithelium. Beneath the epithelial barrier, antigens have access to antigen presenting cells, including dendritic cells, leading to both allergic sensitization and perpetuation of the TH-2 chronic inflammatory response.
|
| Dr. Ikuo Hirano |
The article by Dr. Katzka and his colleagues supports the concept of epithelial barrier defects in EoE through the demonstration of reduced immunohistochemical expression of filaggrin, zonula occludens-3, and claudin-1, important tight junction proteins. Expression was increased in EoE patients treated with topical steroids. Similarly, the study by Dr. van Rhijn and his associates identified impaired mucosal integrity in EoE by a variety of techniques that included electron microscopic demonstration of dilated intercellular spaces, electrical tissue impedance as an in vivo biomarker, and in vitro transepithelial molecular flux in an Ussing chamber. Furthermore, they found that proton pump inhibitor therapy partially restored mucosal permeability defects to a greater degree in patients with PPI-responsive esophageal eosinophilia, compared with patients with EoE. These two studies substantiate studies from the Cincinnati group that previously identified reduced mRNA expression of filaggrin in esophageal mucosal biopsies as well as reduced expression of the intercellular adhesion molecule, desmoglein 1.
In spite of these novel data, the exact role of altered esophageal epithelial permeability in the pathogenesis of EoE is yet unclear. The reversibility of the defect with medical therapy argues against defective cell junction proteins as an intrinsic abnormality. Furthermore, the location of antigen presentation in EoE may occur through other routes such as the small intestine, nasal epithelium, or skin. In the meantime, these studies provide an important advance in our understanding of EoE and open the door to novel therapeutic approaches.
Dr. Ikuo Hirano, AGAF, is professor of medicine at Northwestern University, Chicago. He reported no conflicts of interest.
In the past year, the topic of mucosal integrity in eosinophilic esophagitis has garnered growing attention. Epithelial permeability defects have been described in the pathogenesis of GI disorders, including inflammatory bowel disease and celiac sprue, as well as allergic disorders such as atopic dermatitis. In EoE, both experimental as well as clinical studies have shown an eosinophil-predominant inflammatory response to specific antigens, particularly common food allergens. Increased permeability may predispose genetically susceptible individuals to swallowed allergen penetration through the esophageal epithelium. Beneath the epithelial barrier, antigens have access to antigen presenting cells, including dendritic cells, leading to both allergic sensitization and perpetuation of the TH-2 chronic inflammatory response.
|
| Dr. Ikuo Hirano |
The article by Dr. Katzka and his colleagues supports the concept of epithelial barrier defects in EoE through the demonstration of reduced immunohistochemical expression of filaggrin, zonula occludens-3, and claudin-1, important tight junction proteins. Expression was increased in EoE patients treated with topical steroids. Similarly, the study by Dr. van Rhijn and his associates identified impaired mucosal integrity in EoE by a variety of techniques that included electron microscopic demonstration of dilated intercellular spaces, electrical tissue impedance as an in vivo biomarker, and in vitro transepithelial molecular flux in an Ussing chamber. Furthermore, they found that proton pump inhibitor therapy partially restored mucosal permeability defects to a greater degree in patients with PPI-responsive esophageal eosinophilia, compared with patients with EoE. These two studies substantiate studies from the Cincinnati group that previously identified reduced mRNA expression of filaggrin in esophageal mucosal biopsies as well as reduced expression of the intercellular adhesion molecule, desmoglein 1.
In spite of these novel data, the exact role of altered esophageal epithelial permeability in the pathogenesis of EoE is yet unclear. The reversibility of the defect with medical therapy argues against defective cell junction proteins as an intrinsic abnormality. Furthermore, the location of antigen presentation in EoE may occur through other routes such as the small intestine, nasal epithelium, or skin. In the meantime, these studies provide an important advance in our understanding of EoE and open the door to novel therapeutic approaches.
Dr. Ikuo Hirano, AGAF, is professor of medicine at Northwestern University, Chicago. He reported no conflicts of interest.
Topical steroid therapy improved some indicators of mucosal integrity in patients with eosinophilic esophagitis, but proton pump inhibitor therapy did not, according to two studies reported in the November issue of Clinical Gastroenterology and Hepatology.
The first study found that topical fluticasone therapy at a dose of 880 mcg twice daily for 2 months helped correct esophageal spongiosis, or dilated intercellular space, in patients with eosinophilic esophagitis (EoE). Spongiosis scores for treated patients were significantly lower than for untreated patients (0.4 vs. 1.3; P = .016), said Dr. David Katzka at the Mayo Clinic in Rochester, Minn. and his associates (Clin. Gastroenterol. Hepatol. 2014 [doi:10.1016/j.cgh.2014.02.039]).
In the study, histologic analyses also showed that improved spongiosis scores in treated patients correlated with increased density of two tight junction proteins, filaggrin (P = .001) and zonula occludens-3 (P = .016), said the investigators. These proteins might help regulate antigenic penetration of the esophageal mucosa and also could permit migration of white blood cells, they said. “Loss of tight junction regulators and dilation of intercellular spaces appear to be involved in the pathophysiology of EoE and could be targets for treatment,” the researchers concluded. But they also noted that their study did not examine the same patients before and after steroid therapy and did not look at desmosomes, intercellular junctions that past research has suggested might be affected in EoE.
For the second study, Dr. Bram van Rhijn and his associates at the Academic Medical Center in the Netherlands compared endoscopies of 16 patients with dysphagia and suspected (unconfirmed) EoE with 11 controls, both at baseline and after 8 weeks of high-dose esomeprazole treatment. Esophageal mucosal integrity was “severely impaired” in patients with confirmed EoE and in those with proton pump inhibitor–responsive eosinophilia (PPRE), the researchers said (Clin. Gasteroenterol. Hepatol. 2014 [doi:10.1016/j.cgh.2014.02.037]).
In both forms of disease, molecules as large as 40,000 daltons were able to pass through the compromised esophageal mucosa, Dr. Bram van Rhijn and his associates reported. “This size is similar to the size of most plant and animal food allergens to which EoE patients are sensitized,” they added. Esophageal permeability might increase the rate of immune exposure to allergens, thereby mediating EoE and PPRE, they said.
On mucosal functional tests, both EoE and PPRE were associated with reduced transepithelial electrical resistance and lower electrical tissue impedance, most notably in patients with EoE (P less than .001 for both, compared with controls), the investigators reported. Proton pump inhibitor treatment partially reversed these changes in patients with PPRE but showed no effect for patients with EoE, they said. This finding suggests that acid reflux might play a role in PPRE, but not in EOE, they concluded.
Dr. Katzka and his associates disclosed no funding sources and reported having no conflicts of interest. Dr. Rhijn and his associates were supported by the Netherlands Organization for Scientific Research. Two of Dr. Rhijn’s coauthors reported financial relationships with AstraZeneca, Endostim, Medical Measurement Systems, Shire, and GlaxoSmithKline.
Topical steroid therapy improved some indicators of mucosal integrity in patients with eosinophilic esophagitis, but proton pump inhibitor therapy did not, according to two studies reported in the November issue of Clinical Gastroenterology and Hepatology.
The first study found that topical fluticasone therapy at a dose of 880 mcg twice daily for 2 months helped correct esophageal spongiosis, or dilated intercellular space, in patients with eosinophilic esophagitis (EoE). Spongiosis scores for treated patients were significantly lower than for untreated patients (0.4 vs. 1.3; P = .016), said Dr. David Katzka at the Mayo Clinic in Rochester, Minn. and his associates (Clin. Gastroenterol. Hepatol. 2014 [doi:10.1016/j.cgh.2014.02.039]).
In the study, histologic analyses also showed that improved spongiosis scores in treated patients correlated with increased density of two tight junction proteins, filaggrin (P = .001) and zonula occludens-3 (P = .016), said the investigators. These proteins might help regulate antigenic penetration of the esophageal mucosa and also could permit migration of white blood cells, they said. “Loss of tight junction regulators and dilation of intercellular spaces appear to be involved in the pathophysiology of EoE and could be targets for treatment,” the researchers concluded. But they also noted that their study did not examine the same patients before and after steroid therapy and did not look at desmosomes, intercellular junctions that past research has suggested might be affected in EoE.
For the second study, Dr. Bram van Rhijn and his associates at the Academic Medical Center in the Netherlands compared endoscopies of 16 patients with dysphagia and suspected (unconfirmed) EoE with 11 controls, both at baseline and after 8 weeks of high-dose esomeprazole treatment. Esophageal mucosal integrity was “severely impaired” in patients with confirmed EoE and in those with proton pump inhibitor–responsive eosinophilia (PPRE), the researchers said (Clin. Gasteroenterol. Hepatol. 2014 [doi:10.1016/j.cgh.2014.02.037]).
In both forms of disease, molecules as large as 40,000 daltons were able to pass through the compromised esophageal mucosa, Dr. Bram van Rhijn and his associates reported. “This size is similar to the size of most plant and animal food allergens to which EoE patients are sensitized,” they added. Esophageal permeability might increase the rate of immune exposure to allergens, thereby mediating EoE and PPRE, they said.
On mucosal functional tests, both EoE and PPRE were associated with reduced transepithelial electrical resistance and lower electrical tissue impedance, most notably in patients with EoE (P less than .001 for both, compared with controls), the investigators reported. Proton pump inhibitor treatment partially reversed these changes in patients with PPRE but showed no effect for patients with EoE, they said. This finding suggests that acid reflux might play a role in PPRE, but not in EOE, they concluded.
Dr. Katzka and his associates disclosed no funding sources and reported having no conflicts of interest. Dr. Rhijn and his associates were supported by the Netherlands Organization for Scientific Research. Two of Dr. Rhijn’s coauthors reported financial relationships with AstraZeneca, Endostim, Medical Measurement Systems, Shire, and GlaxoSmithKline.
FROM CLINICAL GASTROENTEROLOGY AND HEPATOLOGY
Key clinical point: Topical steroids seemed to improve mucosal integrity in patients with eosinophilic esophagitis, but proton pump inhibitor therapy did not.
Major finding: Mean spongiosis score was significantly lower among treated vs. untreated patients (0.4 vs. 1.3; P = .016).
Data source: Immunohistochemistry, histology, endoscopy, and mucosal functional analyses of 57 subjects in two separate studies.
Disclosures: Dr. Katzka and associates disclosed no funding sources and reported having no conflicts of interest. Dr. Rhijn and associates were supported by the Netherlands Organization for Scientific Research. Two of Dr. Rhijn’s coauthors reported financial relationships with AstraZeneca, Endostim, Medical Measurement Systems, Shire, and GlaxoSmithKline.
Stage III Non–Small Cell Lung Cancer
Series Editor: Arthur T. Skarin, MD, FACP, FCCP
Each year approximately 228,000 Americans will be diagnosed with lung cancer, and 159,000 will die of this disease. An estimated 85% of lung cancer cases are non–small cell lung cancer (NSCLC), more than 50% of NSCLC is comprised of adenocarcinoma, the median age at diagnosis is 71 years, and 25% of patients with this diagnosis present with stage III disease. In 2010 the seventh edition of the American Joint Committee on Cancer (AJCC) TNM staging system for lung cancer was released, and several changes were made which affect the patient population designated as having stage III disease.
To read the full article in PDF:
Series Editor: Arthur T. Skarin, MD, FACP, FCCP
Each year approximately 228,000 Americans will be diagnosed with lung cancer, and 159,000 will die of this disease. An estimated 85% of lung cancer cases are non–small cell lung cancer (NSCLC), more than 50% of NSCLC is comprised of adenocarcinoma, the median age at diagnosis is 71 years, and 25% of patients with this diagnosis present with stage III disease. In 2010 the seventh edition of the American Joint Committee on Cancer (AJCC) TNM staging system for lung cancer was released, and several changes were made which affect the patient population designated as having stage III disease.
To read the full article in PDF:
Series Editor: Arthur T. Skarin, MD, FACP, FCCP
Each year approximately 228,000 Americans will be diagnosed with lung cancer, and 159,000 will die of this disease. An estimated 85% of lung cancer cases are non–small cell lung cancer (NSCLC), more than 50% of NSCLC is comprised of adenocarcinoma, the median age at diagnosis is 71 years, and 25% of patients with this diagnosis present with stage III disease. In 2010 the seventh edition of the American Joint Committee on Cancer (AJCC) TNM staging system for lung cancer was released, and several changes were made which affect the patient population designated as having stage III disease.
To read the full article in PDF:
CAPO Aspiration Pneumonia
Pneumonia is a common clinical syndrome with well‐described epidemiology and microbiology. Aspiration pneumonia comprises 5% to 15% of patients with pneumonia acquired outside of the hospital,[1] but is less well characterized despite being a major syndrome of pneumonia in the elderly.[2, 3] Difficulties in studying aspiration pneumonia include the lack of a sensitive and specific marker for aspiration as well as the potential overlap between aspiration pneumonia and other forms of pneumonia.[4, 5, 6] Additionally, clinicians have difficulty distinguishing between aspiration pneumonia, which develops after the aspiration of oropharyngeal contents, and aspiration pneumonitis, wherein inhalation of gastric contents causes inflammation without the subsequent development of bacterial infection.[7, 8] Central to the study of aspiration pneumonia is whether it should exist as its own entity, or if aspiration is really a designation used for pneumonia in an older patient with greater comorbidities. The ability to clearly understand how a clinician diagnoses aspiration pneumonia, and whether that method has face validity with expert definitions may allow for improved future research, improved generalizability of current or past research, and possibly better clinical care.
Several validated mortality prediction models exist for community‐acquired pneumonia (CAP) using a variety of clinical predictors, but their performance in patients with aspiration pneumonia is less well characterized. Most studies validating pneumonia severity scoring systems excluded aspiration pneumonia from their study population.[9, 10, 11] Severity scoring systems for CAP may not accurately predict disease severity in patients with aspiration pneumonia. The CURB‐65[9] (confusion, uremia, respiratory rate, blood pressure, age 65 years) and the eCURB[12] scoring systems are poor predictors of mortality in patients with aspiration pneumonia, perhaps because they do not account for patient comorbidities.[13] The pneumonia severity index (PSI)[10] might predict mortality better than CURB‐65 in the aspiration population due to the inclusion of comorbidities.
Previous studies have demonstrated that patients with aspiration pneumonia are older and have greater disease severity and more comorbidities.[13, 14, 15] These single‐center studies also demonstrated greater mortality, more frequent admission to an intensive care unit (ICU), and longer hospital lengths of stay in patients with aspiration pneumonia. These studies identified aspiration pneumonia by the presence of a risk factor for aspiration[15] or by physician billing codes.[13] In practice, however, the bedside clinician diagnoses a patient as having aspiration pneumonia, but the logic is likely vague and inconsistent. Despite the potential for variability with individual judgment, an aggregate estimation from independent judgments may perform better than individual judgments.[16] Because there is no gold standard for defining aspiration pneumonia, all previous research has been limited to definitions created by investigators. This multicenter study seeks to determine what clinical characteristics lead physicians to diagnose a patient as having aspiration pneumonia, and whether or not the clinician‐derived diagnosis is distinct and clinically useful.
Our objectives were to: (1) identify covariates associated with bedside clinicians diagnosing a pneumonia patient as having aspiration pneumonia; (2) compare aspiration pneumonia and nonaspiration pneumonia in regard to disease severity, patient demographics, comorbidities, and clinical outcomes; and (3) measure the performance of the PSI in aspiration pneumonia versus nonaspiration pneumonia.
PATIENTS AND METHODS
Study Design and Setting
We performed a secondary analysis of the Community‐Acquired Pneumonia Organization (CAPO) database, which contains retrospectively collected data from 71 hospitals in 16 countries between June 2001 and December 2012. In each participating center, primary investigators selected nonconsecutive, adult hospitalized patients diagnosed with CAP. To decrease systematic selection biases, the selection of patients with CAP for enrollment in the trial was based on the date of hospital admission. Each investigator completed a case report form that was transferred via the internet to the CAPO study center at the University of Louisville (Louisville, KY). A sample of the data collection form is available at the study website (
Inclusion and Exclusion Criteria
Patients 18 years of age and satisfying criteria for CAP were included in this study. A diagnosis of CAP required a new pulmonary infiltrate at time of hospitalization, and at least 1 of the following: new or increased cough; leukocytosis; leukopenia, or left shift pattern on white blood cell count; and temperature >37.8C or <35.6 C. We excluded patients with pneumonia attributed to mycobacterial or fungal infection, and patients infected with human immunodeficiency virus, as we believed these types of pneumonia differ fundamentally from typical CAP.
Patient Variables
Patient variables included presence of aspiration pneumonia, laboratory data, comorbidities, and measures of disease severity, including the PSI. The clinician made a clinical diagnosis of the presence or absence of aspiration for each patient by marking a box on the case report form. Outcomes included in‐hospital mortality, hospital length of stay up to 14 days, and time to clinical stability up to 8 days. All variables were obtained directly from the case report form. In accordance with previously published definitions, we defined clinical stability as the day the following criteria were all met: improved clinical signs (improved cough and shortness of breath), lack of fever for >8 hours, improving leukocytosis (decreased at least 10% from the previous day), and tolerating oral intake.[17, 18]
Statistical Analysis
Baseline characteristics of patients with aspiration and nonaspiration CAP were compared using 2 or Fisher exact tests for categorical variables and the Mann‐Whitney U test for continuous variables.
To determine which patient variables were important in the physician diagnosis of aspiration pneumonia, we performed logistic regression with initial covariates comprising the demographic, comorbidity, and disease severity measurements listed in Table 1. We included interactions between cerebrovascular disease and age, nursing home status, and confusion to improve model fit. We centered all variables (including binary indicators) according to the method outlined by Kraemer and Blasey to improve interpretation of the main effects.[19]
| Aspiration Pneumonia, N=451 | Nonaspiration Pneumonia, N=4,734 | P Value | |
|---|---|---|---|
|
|||
| Demographics | |||
| Age, y | 79 (6587) | 69 (5380) | <0.001 |
| % Male | 59% | 60% | 0.58 |
| Nursing home residence | 25% | 5% | <0.001 |
| Recent (30 days) antibiotic use | 21% | 16% | 0.017 |
| Comorbidities | |||
| Cerebrovascular disease | 35% | 14% | <0.001 |
| Chronic obstructive pulmonary disease | 25% | 27% | 0.62 |
| Congestive heart failure | 23% | 19% | 0.027 |
| Diabetes | 18% | 18% | 0.85 |
| Cancer | 12% | 10% | 0.12 |
| Renal disease | 10% | 11% | 0.53 |
| Liver disease | 6% | 5% | 0.29 |
| Disease severity | |||
| Pneumonia severity index | 123 (99153) | 92 (68117) | <0.001 |
| Confusion | 49% | 12% | <0.001 |
| PaO2 <60 mm Hg | 43% | 33% | <0.001 |
| BUN >30 g/dL | 42% | 23% | <0.001 |
| Multilobar pneumonia | 34% | 28% | 0.003 |
| Pleural effusion | 25% | 21% | 0.07 |
| Respiratory rate >30 breaths/minute | 21% | 20% | 0.95 |
| pH <7.35 | 13% | 5% | <0.001 |
| Hematocrit <30% | 11% | 6% | 0.001 |
| Temperature >37.8C or <35.6C | 9% | 7% | 0.30 |
| Systolic blood pressure <90 mm Hg | 8% | 9% | 0.003 |
| Sodium <130 mEq/L | 8% | 6% | 0.08 |
| Heart rate >125 beats/minute | 8% | 5% | 0.71 |
| Glucose >250 mg/dL | 6% | 7% | 0.06 |
| Cavitary lesion | 0% | 0% | 0.67 |
| Clinical outcomes | |||
| In‐hospital mortality | 23% | 9% | <0.001 |
| Intensive care unit admission | 19% | 13% | 0.002 |
| Hospital length of stay, d | 9 (515) | 7 (412) | <0.001 |
| Time to clinical stability, d | 8 (48) | 4 (38) | <0.001 |
To determine if aspiration pneumonia had worse clinical outcomes compared to nonaspiration pneumonia, multiple methods were used. To compare the differences between the 2 groups with respect to time to clinical stability and length of hospital stay, we constructed Kaplan‐Meier survival curves and Cox proportional hazards regression models. The log‐rank test was used to determine statistical differences between the Kaplan‐Meier survival curves. To compare the impact of aspiration on mortality in patients with CAP, we conducted a propensity scorematched analysis. We chose propensity score matching over traditional logistic regression to balance variables among groups and to avoid the potential for overfit and multicollinearity. We considered a variable balanced after matching if its standardized difference was <10. All variables in the propensity scorematched analysis were balanced.
Although our dataset contained minimal missing data, we imputed any missing values to maintain the full study population in the creation of the propensity score. Missing data were imputed using the aregImpute function of the hmisc package of R (The R Foundation for Statistical Computing, Vienna, Austria).[20, 21] We built the propensity score model using a variable selection algorithm described by Bursac et al.[22] Our model included variables for region (United States/Canada, Europe, Asia/Africa or Latin America) and the variables listed in Table 1, with the exception of the PSI and the 4 clinical outcomes. Given that previous analyses accounting for clustering by physician did not substantially affect our results,[23] our model did not include physician‐level variables and did not account for the clustering effects of physicians. Using the propensity scores generated from this model, we matched a case of aspiration CAP with a case of nonaspiration CAP.[24] We then constructed a general linear model using the matched dataset to obtain the magnitude of effect of aspiration on mortality.
We used receiver operating characteristic curves to define the diagnostic accuracy of the pneumonia severity index for the prediction of mortality among patients with aspiration pneumonia and those with nonaspiration pneumonia. SAS version 9.3 (SAS Institute, Cary, NC) and R version 2.15.3 (The R Foundation for Statistical Computing) were used for all analyses. P values of 0.05 were considered statistically significant in all analyses.
RESULTS
Our initial query, after exclusion criteria, yielded a study population of 5185 patients (Figure 1). We compared 451 patients diagnosed with aspiration pneumonia to 4734 with CAP (Figure 1). Patient characteristics are summarized in Table 1. Patients with aspiration pneumonia were older, more likely to live in a nursing home, had greater disease severity, and were more likely to be admitted to an ICU. Patients with aspiration pneumonia had longer adjusted hospital lengths of stay and took more days to achieve clinical stability than patients with nonaspiration pneumonia (Figure 2). After adjusting for all variables in Table 1, the Cox proportional hazards models demonstrated that aspiration pneumonia was associated with ongoing hospitalization (hazard ratio [HR] for discharge: 0.77, 95% confidence interval [CI]: 0.65‐0.91, P=0.002) and clinical instability (HR for attaining clinical stability: 0.72, 95% CI: 0.61‐0.84, P<0.001). Patients with aspiration pneumonia presented with greater disease severity than those with nonaspiration pneumonia. Although there was no difference between groups in regard to temperature, respiratory rate, hyponatremia, or presence of pleural effusions or cavitary lesions, all other measured indices of disease severity were worse in patients with aspiration pneumonia. Patients with aspiration pneumonia were more likely to have cerebrovascular disease than those with nonaspiration pneumonia. Aspiration pneumonia patients also had increased prevalence of congestive heart failure. There was no appreciable difference between groups among other measured comorbidities.
The patient characteristics most associated with a physician diagnosis of aspiration pneumonia, identified using logistic regression, were confusion, residence in nursing home, and presence of cerebrovascular disease (odds ratio [OR]: of 4.4, 2.9, and 2.3, respectively), whereas renal disease was associated with decreased physician diagnosis of aspiration pneumonia over nonaspiration pneumonia (OR: 0.58) (Table 2).
| Covariate | Odds Ratio | 95% Confidence Intervals | P Value |
|---|---|---|---|
|
|||
| Demographics | |||
| Age, y | 1.00 | 0.991.01 | 0.948 |
| Male | 1.20 | 0.941.54 | 0.148 |
| Nursing home residence | 2.93 | 2.134.00 | <0.001 |
| Comorbidities | |||
| Cerebrovascular disease | 2.26 | 1.533.32 | <0.001 |
| Renal disease | 0.58 | 0.390.85 | 0.006 |
| Disease severity | |||
| Confusion | 4.41 | 3.405.72 | <0.001 |
| Hematocrit <30% | 1.59 | 1.062.33 | 0.020 |
| pH <7.35 | 1.67 | 1.102.47 | 0.013 |
| Temperature >37.8C or <35.6C | 1.60 | 1.072.35 | 0.019 |
| Multilobar pneumonia | 1.29 | 1.001.65 | 0.047 |
| Interaction terms | |||
| Age * cerebrovascular disease | 0.98 | 0.960.99 | 0.011 |
| Nursing home * cerebrovascular disease | 0.51 | 0.270.96 | 0.037 |
| Confusion * cerebrovascular disease | 0.70 | 0.421.17 | 0.175 |
Observed in‐patient mortality of aspiration pneumonia was 23%. This mortality was considerably higher than a mean PSI score of 123 would predict (class IV risk group, with expected 30‐day mortality of 8%9%[25]). The PSI score's ability to predict inpatient mortality in patients with aspiration pneumonia was moderate, with an area under the curve (AUC) of 0.71. This was similar to its performance in patients with nonaspiration pneumonia (AUC of 0.75) (Figure 3). These values are lower than the AUC of 0.81 for the PSI in predicting mortality derived from a meta‐analysis of 31 other studies.[26]
Our regression model after propensity score matching demonstrated that aspiration pneumonia independently confers a 2.3‐fold increased odds for inpatient mortality (95% CI: 1.56‐3.45, P<0.001).
DISCUSSION
Pneumonia patients with confusion, nursing home residence, or cerebrovascular disease are more likely to be diagnosed with aspiration pneumonia by clinicians. Although this is unsurprising, it is notable that these patients are more than twice as likely to die in the inpatient setting, even after accounting for age, comorbidities, and disease severity. These findings are similar to three previously published studies comparing aspiration and nonaspiration pneumonia at single institutions, albeit using different aspiration pneumonia definitions.[13, 14, 15] This study is the first large, multicenter, multinational study to demonstrate these findings.
Central to the interpretation of our results is the method of diagnosing aspiration versus nonaspiration. A bottom‐up method that relies on a clinician to check a box for aspiration may appear poorly reproducible. Because there is no diagnostic gold standard, clinicians may use different criteria to diagnose aspiration, creating potential for idiosyncratic noise. The strength of the wisdom of the crowd method used in this study is that an aggregate estimation from independent judgments may reduce the noise from individual judgments.[16] Although clinicians may vary in why they diagnose a particular patient as having aspiration pneumonia, it appears that the overwhelming reason for diagnosing a patient as having aspiration pneumonia is the presence of confusion, followed by previous nursing home residence or cerebrovascular disease. This finding has some face validity when compared with studies using an investigator definition, as altered mental status, chronic debility, and cerebrovascular disease are either prominent features of the definition of aspiration pneumonia[8] or frequently observed in patients with aspiration pneumonia.[13, 15] The distribution of cerebrovascular disease among our study's aspiration and nonaspiration pneumonia patients was similar to studies that used formal criteria in their definitions.[13, 15] Although nursing home residence was more likely in aspiration pneumonia patients, the majority of aspiration pneumonia patients were residing in the community, suggesting that aspiration is not simply a surrogate for healthcare‐associated pneumonia. Although patients with aspiration pneumonia are typically older than their nonaspiration counterparts, it appears that age is not a key determinant in the diagnosis of aspiration. With aspiration pneumonia, confusion, nursing home residence, and the presence of cerebrovascular disease are the greatest contributors in the clinical diagnosis, more than age.
Our data demonstrate that aspiration pneumonia confers increased odds for mortality, even after adjustment for age, disease severity, and comorbidities. These data suggest that aspiration pneumonia is a distinct entity from nonaspiration pneumonia, and that this disease is worse than nonaspiration CAP. If aspiration pneumonia is distinct from nonaspiration pneumonia, some unrecognized host factor other than age, disease severity, or the captured comorbidities decreases survival in aspiration pneumonia patients. However, it is also possible that aspiration pneumonia is merely a clinical designation for one end of the pneumonia spectrum, and we and others have failed to completely account for all measures of disease severity or all measures of comorbidities. Examples of unmeasured comorbidities would include presence of oropharyngeal dysphagia, which is not assessed in the database but could have a significant effect on clinical diagnosis. Unmeasured covariates can include measures beyond that of disease severity or comorbidity, such as the presence of a do not resuscitate (DNR) order, which could have a significant confounding effect on the observed association. A previous, single‐center study demonstrated that increased 30‐day mortality in aspiration pneumonia was mostly attributable to greater disease severity and comorbidities, although aspiration pneumonia independently conferred greater risk for adverse long‐term outcomes.[15] We propose that aspiration pneumonia represents a clinically distinct entity from nonaspiration pneumonia. Patients with chronic aspiration are often chronically malnourished and may have different oral flora than patients without chronic aspiration.[27, 28] Chronic aspiration has been associated with granulomatous reaction, organizing pneumonia, diffuse alveolar damage, and chronic bronchiolitis.[29] Chronic aspiration may elicit changes in the host physiology, and may render the host more susceptible to the development of secondary bacterial infection with morbid consequences.
The ability of the PSI to predict inpatient mortality was moderate (AUC only 0.7), with no significant additional discrimination between the aspiration and nonaspiration pneumonia groups. Although the PSI had moderate ability to predict inpatient mortality, the observed mortality was considerably higher than predicted. It is possible that the PSI incompletely captures clinically relevant comorbidities (eg, malnutrition). Further study to improve mortality prediction of aspiration pneumonia patients could employ sensitivity analysis to determine optimal thresholds and weighting of the PSI components.
Patients with aspiration pneumonia had longer hospital lengths of stay and took longer to achieve clinical stability than their nonaspiration counterparts. Time to clinical stability has been associated with increased posthospitalization mortality and is associated with time to switch from intravenous to oral antibiotics.[17] Although some component of hospital length‐of‐stay is subject to local practice patterns, time to clinical stability has explicit criteria for clinical improvement and failure, and therefore is less likely to be affected by local practice patterns.
We noted a relatively high (16%21%) incidence of prior antibiotic use among patients in this database. Analysis of antibiotic prescription patterns was limited, given the several different countries from which the database draws its cases. Although we used accepted criteria to define CAP cases, it is possible that this population may have a higher rate of resistant or uncommon pathogens than other studies of CAP that have populations with lower incidence of prior antibiotic use. Although not assessed, we suspect a significant component of the prior antibiotic use represented outpatient pneumonia treatment during the few days prior to visiting the hospital.
This study has several limitations, of which the most important may be that we used clinical determination for defining presence of aspiration pneumonia. This method is susceptible to the subjective perceptions of the treating clinician. We did not account for the effect of individual physicians in our model, although we did adjust for regional differences. The retrospective identification of patients allows for the possibility of selection bias, and therefore we have not attempted to make inferences regarding the relative incidence of pneumonia, nor did we adjust for temporal trends in diagnosis. The ratio of aspiration pneumonia patients to nonaspiration pneumonia patients may not necessarily reflect that observed in reality. Microbiologic and antibiotic data were unavailable for analysis. This study cannot inform on nonhospitalized patients with aspiration pneumonia, as only hospitalized patients were enrolled. The database identified cases of pneumonia, so it is possible for a patient to enter into the database more than once. Detection of mortality was limited to the inpatient setting rather than a set interval of 30 days. Inpatient mortality depends on length‐of‐stay patterns that may bias the mortality endpoint.[30] Also not assessed was the presence of a DNR order. It is possible that an older patient with greater comorbidities and disease severity may have care intentionally limited or withdrawn early by the family or clinicians.
Strengths of the study include its size and its multicenter, multinational population. The CAPO database is a large and well‐described population of patients with CAP.[17, 31] These attributes, as well as the clinician‐determined diagnosis, increase the generalizability of the study compared to a single‐center, single‐country study that employs investigator‐defined criteria.
CONCLUSION
Pneumonia patients with confusion, who are nursing home residence, and have cerebrovascular disease are more likely to be diagnosed with aspiration pneumonia by clinicians. Our clinician‐diagnosed cohort appears similar to those derived using an investigator definition. Patients with aspiration pneumonia are older, and have greater disease severity and more comorbidities than patients with nonaspiration pneumonia. They have greater mortality than their PSI score class would predict. Even after accounting for age, disease severity, and comorbidities, the presence of aspiration pneumonia independently conferred a greater than 2‐fold increase in inpatient mortality. These findings together suggest that aspiration pneumonia should be considered a distinct entity from typical pneumonia, and that additional research should be done in this field.
ACKNOWLEDGMENTS
Disclosures: M.J.L. contributed to the study design, data analysis, statistical analysis, and writing of the manuscript. P.P. contributed to the study design and revision of the manuscript for important intellectual content. T.W. and E.W. contributed to the study design, statistical analysis, and revision of the manuscript for important intellectual content. J.A.R. and N.C.D. contributed to the study design and revision of the manuscript for important intellectual content. All authors read and approved the final manuscript. M.L. takes responsibility for the integrity of the work as a whole, from inception to published article. This investigation was partly supported with funding from the National Center for Research Resources and the National Center for Advancing Translational Sciences, National Institutes of Health (grant 8UL1TR000105 [formerly UL1RR025764]). The authors report no conflicts of interest.
- , , , et al. Severe community‐acquired pneumonia. Epidemiology and prognostic factors. Am Rev Respir Dis. 1991;144(2):312–318.
- , , . Risk factors for pneumonia in the elderly. Am J Med. 1994;96(4):313–320.
- , . Aspiration pneumonia and dysphagia in the elderly. Chest. 2003;124(1):328–336.
- , , . Pneumonia versus aspiration pneumonitis in nursing home residents: diagnosis and management. J Am Geriatr Soc. 2003;51(1):17–23.
- . Aspiration pneumonia: mixing apples with oranges and tangerines. Crit Care Med. 2004;32(5):1236; author reply 1236–1237.
- , , , , . Epidemiology and impact of aspiration pneumonia in patients undergoing surgery in Maryland, 1999–2000. Crit Care Med. 2003;31(7):1930–1937.
- . Aspiration syndromes: aspiration pneumonia and pneumonitis. Hosp Pract (Minneap). 2010;38(1):35–42.
- . Aspiration pneumonitis and aspiration pneumonia. N Engl J Med. 2001;344(9):665–671.
- , , , et al. Defining community acquired pneumonia severity on presentation to hospital: an international derivation and validation study. Thorax. 2003;58(5):377–382.
- , , , et al. Comparison of a disease‐specific and a generic severity of illness measure for patients with community‐acquired pneumonia. J Gen Intern Med. 1995;10(7):359–368.
- , , , et al. Development and validation of a clinical prediction rule for severe community‐acquired pneumonia. Am J Respir Crit Care Med. 2006;174(11):1249–1256.
- , , , et al. CURB‐65 pneumonia severity assessment adapted for electronic decision support. Chest. 2011;140(1):156–163.
- , , , . Mortality, morbidity, and disease severity of patients with aspiration pneumonia. J Hosp Med. 2013;8(2):83–90.
- , , , , . Pneumonia Severity Index (PSI), CURB‐65, and mortality in hospitalized elderly patients with aspiration pneumonia [in German]. Z Gerontol Geriatr. 2011;44(4):229–234.
- , , , , . Risk factors for aspiration in community‐acquired pneumonia: analysis of a hospitalized UK cohort. Am J Med. 2013;126(11):995–1001.
- , , , . The wisdom of the crowd in combinatorial problems. Cogn Sci. 2012;36(3):452–470.
- , , , et al. Association between time to clinical stability and outcomes after discharge in hospitalized patients with community‐acquired pneumonia. Chest. 2011;140(2):482–488.
- . Clinical stability and switch therapy in hospitalised patients with community‐acquired pneumonia: are we there yet? Eur Respir J. 2013;41(1):5–6.
- , . Centring in regression analyses: a strategy to prevent errors in statistical inference. Int J Methods Psychiatr Res. 2004;13(3):141–151.
- . Hmisc: Harrell miscellaneous. Available at: http://CRAN.R‐project.org/package=Hmisc. Published Sept 12, 2014. Last accessed Oct 27, 2014.
- , . Multiple imputation for the fatal accident reporting system. J R Stat Soc Ser C Appl Stat. 1991;40(1):13–29.
- , , , . Purposeful selection of variables in logistic regression. Source Code Biol Med. 2008;3:17.
- , , , , ; CAPO authors. Mortality differences among hospitalized patients with community‐acquired pneumonia in three world regions: results from the Community‐Acquired Pneumonia Organization (CAPO) International Cohort Study. Respir Med. 2013;107(7):1101–1111.
- . Reducing bias in a propensity score matched‐pair sample using greedy matching techniques. In: Proceedings of the 26th Annual SAS Users Group International Conference. Cary, NC: SAS Institute Inc.; 2001:214–226. Available at: http://www2.sas.com/proceedings/sugi26/p214–26.pdf. Last accessed Oct 27, 2014.
- , , , et al. A prediction rule to identify low‐risk patients with community‐acquired pneumonia. N Engl J Med. 1997;336(4):243–250.
- , , , et al. Severity assessment tools for predicting mortality in hospitalised patients with community‐acquired pneumonia. Systematic review and meta‐analysis. Thorax. 2010;65(10):878–883.
- , , , , , . Prevalence and prognostic implications of dysphagia in elderly patients with pneumonia. Age Ageing. 2010;39(1):39–45.
- , . The association between oral microorgansims and aspiration pneumonia in the institutionalized elderly: review and recommendations. Dysphagia. 2010;25(4):307–322.
- , . Histopathology of aspiration pneumonia not associated with food or other particulate matter: a clinicopathologic study of 10 cases diagnosed on biopsy. Am J Surg Pathol. 2011;35(3):426–431.
- , , , , , . Interpreting hospital mortality data. The role of clinical risk adjustment. JAMA. 1988;260(24):3611–3616.
- , , , . Hospitalization for community‐acquired pneumonia: the pneumonia severity index vs clinical judgment. Chest. 2003;124(1):121–124.
Pneumonia is a common clinical syndrome with well‐described epidemiology and microbiology. Aspiration pneumonia comprises 5% to 15% of patients with pneumonia acquired outside of the hospital,[1] but is less well characterized despite being a major syndrome of pneumonia in the elderly.[2, 3] Difficulties in studying aspiration pneumonia include the lack of a sensitive and specific marker for aspiration as well as the potential overlap between aspiration pneumonia and other forms of pneumonia.[4, 5, 6] Additionally, clinicians have difficulty distinguishing between aspiration pneumonia, which develops after the aspiration of oropharyngeal contents, and aspiration pneumonitis, wherein inhalation of gastric contents causes inflammation without the subsequent development of bacterial infection.[7, 8] Central to the study of aspiration pneumonia is whether it should exist as its own entity, or if aspiration is really a designation used for pneumonia in an older patient with greater comorbidities. The ability to clearly understand how a clinician diagnoses aspiration pneumonia, and whether that method has face validity with expert definitions may allow for improved future research, improved generalizability of current or past research, and possibly better clinical care.
Several validated mortality prediction models exist for community‐acquired pneumonia (CAP) using a variety of clinical predictors, but their performance in patients with aspiration pneumonia is less well characterized. Most studies validating pneumonia severity scoring systems excluded aspiration pneumonia from their study population.[9, 10, 11] Severity scoring systems for CAP may not accurately predict disease severity in patients with aspiration pneumonia. The CURB‐65[9] (confusion, uremia, respiratory rate, blood pressure, age 65 years) and the eCURB[12] scoring systems are poor predictors of mortality in patients with aspiration pneumonia, perhaps because they do not account for patient comorbidities.[13] The pneumonia severity index (PSI)[10] might predict mortality better than CURB‐65 in the aspiration population due to the inclusion of comorbidities.
Previous studies have demonstrated that patients with aspiration pneumonia are older and have greater disease severity and more comorbidities.[13, 14, 15] These single‐center studies also demonstrated greater mortality, more frequent admission to an intensive care unit (ICU), and longer hospital lengths of stay in patients with aspiration pneumonia. These studies identified aspiration pneumonia by the presence of a risk factor for aspiration[15] or by physician billing codes.[13] In practice, however, the bedside clinician diagnoses a patient as having aspiration pneumonia, but the logic is likely vague and inconsistent. Despite the potential for variability with individual judgment, an aggregate estimation from independent judgments may perform better than individual judgments.[16] Because there is no gold standard for defining aspiration pneumonia, all previous research has been limited to definitions created by investigators. This multicenter study seeks to determine what clinical characteristics lead physicians to diagnose a patient as having aspiration pneumonia, and whether or not the clinician‐derived diagnosis is distinct and clinically useful.
Our objectives were to: (1) identify covariates associated with bedside clinicians diagnosing a pneumonia patient as having aspiration pneumonia; (2) compare aspiration pneumonia and nonaspiration pneumonia in regard to disease severity, patient demographics, comorbidities, and clinical outcomes; and (3) measure the performance of the PSI in aspiration pneumonia versus nonaspiration pneumonia.
PATIENTS AND METHODS
Study Design and Setting
We performed a secondary analysis of the Community‐Acquired Pneumonia Organization (CAPO) database, which contains retrospectively collected data from 71 hospitals in 16 countries between June 2001 and December 2012. In each participating center, primary investigators selected nonconsecutive, adult hospitalized patients diagnosed with CAP. To decrease systematic selection biases, the selection of patients with CAP for enrollment in the trial was based on the date of hospital admission. Each investigator completed a case report form that was transferred via the internet to the CAPO study center at the University of Louisville (Louisville, KY). A sample of the data collection form is available at the study website (
Inclusion and Exclusion Criteria
Patients 18 years of age and satisfying criteria for CAP were included in this study. A diagnosis of CAP required a new pulmonary infiltrate at time of hospitalization, and at least 1 of the following: new or increased cough; leukocytosis; leukopenia, or left shift pattern on white blood cell count; and temperature >37.8C or <35.6 C. We excluded patients with pneumonia attributed to mycobacterial or fungal infection, and patients infected with human immunodeficiency virus, as we believed these types of pneumonia differ fundamentally from typical CAP.
Patient Variables
Patient variables included presence of aspiration pneumonia, laboratory data, comorbidities, and measures of disease severity, including the PSI. The clinician made a clinical diagnosis of the presence or absence of aspiration for each patient by marking a box on the case report form. Outcomes included in‐hospital mortality, hospital length of stay up to 14 days, and time to clinical stability up to 8 days. All variables were obtained directly from the case report form. In accordance with previously published definitions, we defined clinical stability as the day the following criteria were all met: improved clinical signs (improved cough and shortness of breath), lack of fever for >8 hours, improving leukocytosis (decreased at least 10% from the previous day), and tolerating oral intake.[17, 18]
Statistical Analysis
Baseline characteristics of patients with aspiration and nonaspiration CAP were compared using 2 or Fisher exact tests for categorical variables and the Mann‐Whitney U test for continuous variables.
To determine which patient variables were important in the physician diagnosis of aspiration pneumonia, we performed logistic regression with initial covariates comprising the demographic, comorbidity, and disease severity measurements listed in Table 1. We included interactions between cerebrovascular disease and age, nursing home status, and confusion to improve model fit. We centered all variables (including binary indicators) according to the method outlined by Kraemer and Blasey to improve interpretation of the main effects.[19]
| Aspiration Pneumonia, N=451 | Nonaspiration Pneumonia, N=4,734 | P Value | |
|---|---|---|---|
|
|||
| Demographics | |||
| Age, y | 79 (6587) | 69 (5380) | <0.001 |
| % Male | 59% | 60% | 0.58 |
| Nursing home residence | 25% | 5% | <0.001 |
| Recent (30 days) antibiotic use | 21% | 16% | 0.017 |
| Comorbidities | |||
| Cerebrovascular disease | 35% | 14% | <0.001 |
| Chronic obstructive pulmonary disease | 25% | 27% | 0.62 |
| Congestive heart failure | 23% | 19% | 0.027 |
| Diabetes | 18% | 18% | 0.85 |
| Cancer | 12% | 10% | 0.12 |
| Renal disease | 10% | 11% | 0.53 |
| Liver disease | 6% | 5% | 0.29 |
| Disease severity | |||
| Pneumonia severity index | 123 (99153) | 92 (68117) | <0.001 |
| Confusion | 49% | 12% | <0.001 |
| PaO2 <60 mm Hg | 43% | 33% | <0.001 |
| BUN >30 g/dL | 42% | 23% | <0.001 |
| Multilobar pneumonia | 34% | 28% | 0.003 |
| Pleural effusion | 25% | 21% | 0.07 |
| Respiratory rate >30 breaths/minute | 21% | 20% | 0.95 |
| pH <7.35 | 13% | 5% | <0.001 |
| Hematocrit <30% | 11% | 6% | 0.001 |
| Temperature >37.8C or <35.6C | 9% | 7% | 0.30 |
| Systolic blood pressure <90 mm Hg | 8% | 9% | 0.003 |
| Sodium <130 mEq/L | 8% | 6% | 0.08 |
| Heart rate >125 beats/minute | 8% | 5% | 0.71 |
| Glucose >250 mg/dL | 6% | 7% | 0.06 |
| Cavitary lesion | 0% | 0% | 0.67 |
| Clinical outcomes | |||
| In‐hospital mortality | 23% | 9% | <0.001 |
| Intensive care unit admission | 19% | 13% | 0.002 |
| Hospital length of stay, d | 9 (515) | 7 (412) | <0.001 |
| Time to clinical stability, d | 8 (48) | 4 (38) | <0.001 |
To determine if aspiration pneumonia had worse clinical outcomes compared to nonaspiration pneumonia, multiple methods were used. To compare the differences between the 2 groups with respect to time to clinical stability and length of hospital stay, we constructed Kaplan‐Meier survival curves and Cox proportional hazards regression models. The log‐rank test was used to determine statistical differences between the Kaplan‐Meier survival curves. To compare the impact of aspiration on mortality in patients with CAP, we conducted a propensity scorematched analysis. We chose propensity score matching over traditional logistic regression to balance variables among groups and to avoid the potential for overfit and multicollinearity. We considered a variable balanced after matching if its standardized difference was <10. All variables in the propensity scorematched analysis were balanced.
Although our dataset contained minimal missing data, we imputed any missing values to maintain the full study population in the creation of the propensity score. Missing data were imputed using the aregImpute function of the hmisc package of R (The R Foundation for Statistical Computing, Vienna, Austria).[20, 21] We built the propensity score model using a variable selection algorithm described by Bursac et al.[22] Our model included variables for region (United States/Canada, Europe, Asia/Africa or Latin America) and the variables listed in Table 1, with the exception of the PSI and the 4 clinical outcomes. Given that previous analyses accounting for clustering by physician did not substantially affect our results,[23] our model did not include physician‐level variables and did not account for the clustering effects of physicians. Using the propensity scores generated from this model, we matched a case of aspiration CAP with a case of nonaspiration CAP.[24] We then constructed a general linear model using the matched dataset to obtain the magnitude of effect of aspiration on mortality.
We used receiver operating characteristic curves to define the diagnostic accuracy of the pneumonia severity index for the prediction of mortality among patients with aspiration pneumonia and those with nonaspiration pneumonia. SAS version 9.3 (SAS Institute, Cary, NC) and R version 2.15.3 (The R Foundation for Statistical Computing) were used for all analyses. P values of 0.05 were considered statistically significant in all analyses.
RESULTS
Our initial query, after exclusion criteria, yielded a study population of 5185 patients (Figure 1). We compared 451 patients diagnosed with aspiration pneumonia to 4734 with CAP (Figure 1). Patient characteristics are summarized in Table 1. Patients with aspiration pneumonia were older, more likely to live in a nursing home, had greater disease severity, and were more likely to be admitted to an ICU. Patients with aspiration pneumonia had longer adjusted hospital lengths of stay and took more days to achieve clinical stability than patients with nonaspiration pneumonia (Figure 2). After adjusting for all variables in Table 1, the Cox proportional hazards models demonstrated that aspiration pneumonia was associated with ongoing hospitalization (hazard ratio [HR] for discharge: 0.77, 95% confidence interval [CI]: 0.65‐0.91, P=0.002) and clinical instability (HR for attaining clinical stability: 0.72, 95% CI: 0.61‐0.84, P<0.001). Patients with aspiration pneumonia presented with greater disease severity than those with nonaspiration pneumonia. Although there was no difference between groups in regard to temperature, respiratory rate, hyponatremia, or presence of pleural effusions or cavitary lesions, all other measured indices of disease severity were worse in patients with aspiration pneumonia. Patients with aspiration pneumonia were more likely to have cerebrovascular disease than those with nonaspiration pneumonia. Aspiration pneumonia patients also had increased prevalence of congestive heart failure. There was no appreciable difference between groups among other measured comorbidities.
The patient characteristics most associated with a physician diagnosis of aspiration pneumonia, identified using logistic regression, were confusion, residence in nursing home, and presence of cerebrovascular disease (odds ratio [OR]: of 4.4, 2.9, and 2.3, respectively), whereas renal disease was associated with decreased physician diagnosis of aspiration pneumonia over nonaspiration pneumonia (OR: 0.58) (Table 2).
| Covariate | Odds Ratio | 95% Confidence Intervals | P Value |
|---|---|---|---|
|
|||
| Demographics | |||
| Age, y | 1.00 | 0.991.01 | 0.948 |
| Male | 1.20 | 0.941.54 | 0.148 |
| Nursing home residence | 2.93 | 2.134.00 | <0.001 |
| Comorbidities | |||
| Cerebrovascular disease | 2.26 | 1.533.32 | <0.001 |
| Renal disease | 0.58 | 0.390.85 | 0.006 |
| Disease severity | |||
| Confusion | 4.41 | 3.405.72 | <0.001 |
| Hematocrit <30% | 1.59 | 1.062.33 | 0.020 |
| pH <7.35 | 1.67 | 1.102.47 | 0.013 |
| Temperature >37.8C or <35.6C | 1.60 | 1.072.35 | 0.019 |
| Multilobar pneumonia | 1.29 | 1.001.65 | 0.047 |
| Interaction terms | |||
| Age * cerebrovascular disease | 0.98 | 0.960.99 | 0.011 |
| Nursing home * cerebrovascular disease | 0.51 | 0.270.96 | 0.037 |
| Confusion * cerebrovascular disease | 0.70 | 0.421.17 | 0.175 |
Observed in‐patient mortality of aspiration pneumonia was 23%. This mortality was considerably higher than a mean PSI score of 123 would predict (class IV risk group, with expected 30‐day mortality of 8%9%[25]). The PSI score's ability to predict inpatient mortality in patients with aspiration pneumonia was moderate, with an area under the curve (AUC) of 0.71. This was similar to its performance in patients with nonaspiration pneumonia (AUC of 0.75) (Figure 3). These values are lower than the AUC of 0.81 for the PSI in predicting mortality derived from a meta‐analysis of 31 other studies.[26]
Our regression model after propensity score matching demonstrated that aspiration pneumonia independently confers a 2.3‐fold increased odds for inpatient mortality (95% CI: 1.56‐3.45, P<0.001).
DISCUSSION
Pneumonia patients with confusion, nursing home residence, or cerebrovascular disease are more likely to be diagnosed with aspiration pneumonia by clinicians. Although this is unsurprising, it is notable that these patients are more than twice as likely to die in the inpatient setting, even after accounting for age, comorbidities, and disease severity. These findings are similar to three previously published studies comparing aspiration and nonaspiration pneumonia at single institutions, albeit using different aspiration pneumonia definitions.[13, 14, 15] This study is the first large, multicenter, multinational study to demonstrate these findings.
Central to the interpretation of our results is the method of diagnosing aspiration versus nonaspiration. A bottom‐up method that relies on a clinician to check a box for aspiration may appear poorly reproducible. Because there is no diagnostic gold standard, clinicians may use different criteria to diagnose aspiration, creating potential for idiosyncratic noise. The strength of the wisdom of the crowd method used in this study is that an aggregate estimation from independent judgments may reduce the noise from individual judgments.[16] Although clinicians may vary in why they diagnose a particular patient as having aspiration pneumonia, it appears that the overwhelming reason for diagnosing a patient as having aspiration pneumonia is the presence of confusion, followed by previous nursing home residence or cerebrovascular disease. This finding has some face validity when compared with studies using an investigator definition, as altered mental status, chronic debility, and cerebrovascular disease are either prominent features of the definition of aspiration pneumonia[8] or frequently observed in patients with aspiration pneumonia.[13, 15] The distribution of cerebrovascular disease among our study's aspiration and nonaspiration pneumonia patients was similar to studies that used formal criteria in their definitions.[13, 15] Although nursing home residence was more likely in aspiration pneumonia patients, the majority of aspiration pneumonia patients were residing in the community, suggesting that aspiration is not simply a surrogate for healthcare‐associated pneumonia. Although patients with aspiration pneumonia are typically older than their nonaspiration counterparts, it appears that age is not a key determinant in the diagnosis of aspiration. With aspiration pneumonia, confusion, nursing home residence, and the presence of cerebrovascular disease are the greatest contributors in the clinical diagnosis, more than age.
Our data demonstrate that aspiration pneumonia confers increased odds for mortality, even after adjustment for age, disease severity, and comorbidities. These data suggest that aspiration pneumonia is a distinct entity from nonaspiration pneumonia, and that this disease is worse than nonaspiration CAP. If aspiration pneumonia is distinct from nonaspiration pneumonia, some unrecognized host factor other than age, disease severity, or the captured comorbidities decreases survival in aspiration pneumonia patients. However, it is also possible that aspiration pneumonia is merely a clinical designation for one end of the pneumonia spectrum, and we and others have failed to completely account for all measures of disease severity or all measures of comorbidities. Examples of unmeasured comorbidities would include presence of oropharyngeal dysphagia, which is not assessed in the database but could have a significant effect on clinical diagnosis. Unmeasured covariates can include measures beyond that of disease severity or comorbidity, such as the presence of a do not resuscitate (DNR) order, which could have a significant confounding effect on the observed association. A previous, single‐center study demonstrated that increased 30‐day mortality in aspiration pneumonia was mostly attributable to greater disease severity and comorbidities, although aspiration pneumonia independently conferred greater risk for adverse long‐term outcomes.[15] We propose that aspiration pneumonia represents a clinically distinct entity from nonaspiration pneumonia. Patients with chronic aspiration are often chronically malnourished and may have different oral flora than patients without chronic aspiration.[27, 28] Chronic aspiration has been associated with granulomatous reaction, organizing pneumonia, diffuse alveolar damage, and chronic bronchiolitis.[29] Chronic aspiration may elicit changes in the host physiology, and may render the host more susceptible to the development of secondary bacterial infection with morbid consequences.
The ability of the PSI to predict inpatient mortality was moderate (AUC only 0.7), with no significant additional discrimination between the aspiration and nonaspiration pneumonia groups. Although the PSI had moderate ability to predict inpatient mortality, the observed mortality was considerably higher than predicted. It is possible that the PSI incompletely captures clinically relevant comorbidities (eg, malnutrition). Further study to improve mortality prediction of aspiration pneumonia patients could employ sensitivity analysis to determine optimal thresholds and weighting of the PSI components.
Patients with aspiration pneumonia had longer hospital lengths of stay and took longer to achieve clinical stability than their nonaspiration counterparts. Time to clinical stability has been associated with increased posthospitalization mortality and is associated with time to switch from intravenous to oral antibiotics.[17] Although some component of hospital length‐of‐stay is subject to local practice patterns, time to clinical stability has explicit criteria for clinical improvement and failure, and therefore is less likely to be affected by local practice patterns.
We noted a relatively high (16%21%) incidence of prior antibiotic use among patients in this database. Analysis of antibiotic prescription patterns was limited, given the several different countries from which the database draws its cases. Although we used accepted criteria to define CAP cases, it is possible that this population may have a higher rate of resistant or uncommon pathogens than other studies of CAP that have populations with lower incidence of prior antibiotic use. Although not assessed, we suspect a significant component of the prior antibiotic use represented outpatient pneumonia treatment during the few days prior to visiting the hospital.
This study has several limitations, of which the most important may be that we used clinical determination for defining presence of aspiration pneumonia. This method is susceptible to the subjective perceptions of the treating clinician. We did not account for the effect of individual physicians in our model, although we did adjust for regional differences. The retrospective identification of patients allows for the possibility of selection bias, and therefore we have not attempted to make inferences regarding the relative incidence of pneumonia, nor did we adjust for temporal trends in diagnosis. The ratio of aspiration pneumonia patients to nonaspiration pneumonia patients may not necessarily reflect that observed in reality. Microbiologic and antibiotic data were unavailable for analysis. This study cannot inform on nonhospitalized patients with aspiration pneumonia, as only hospitalized patients were enrolled. The database identified cases of pneumonia, so it is possible for a patient to enter into the database more than once. Detection of mortality was limited to the inpatient setting rather than a set interval of 30 days. Inpatient mortality depends on length‐of‐stay patterns that may bias the mortality endpoint.[30] Also not assessed was the presence of a DNR order. It is possible that an older patient with greater comorbidities and disease severity may have care intentionally limited or withdrawn early by the family or clinicians.
Strengths of the study include its size and its multicenter, multinational population. The CAPO database is a large and well‐described population of patients with CAP.[17, 31] These attributes, as well as the clinician‐determined diagnosis, increase the generalizability of the study compared to a single‐center, single‐country study that employs investigator‐defined criteria.
CONCLUSION
Pneumonia patients with confusion, who are nursing home residence, and have cerebrovascular disease are more likely to be diagnosed with aspiration pneumonia by clinicians. Our clinician‐diagnosed cohort appears similar to those derived using an investigator definition. Patients with aspiration pneumonia are older, and have greater disease severity and more comorbidities than patients with nonaspiration pneumonia. They have greater mortality than their PSI score class would predict. Even after accounting for age, disease severity, and comorbidities, the presence of aspiration pneumonia independently conferred a greater than 2‐fold increase in inpatient mortality. These findings together suggest that aspiration pneumonia should be considered a distinct entity from typical pneumonia, and that additional research should be done in this field.
ACKNOWLEDGMENTS
Disclosures: M.J.L. contributed to the study design, data analysis, statistical analysis, and writing of the manuscript. P.P. contributed to the study design and revision of the manuscript for important intellectual content. T.W. and E.W. contributed to the study design, statistical analysis, and revision of the manuscript for important intellectual content. J.A.R. and N.C.D. contributed to the study design and revision of the manuscript for important intellectual content. All authors read and approved the final manuscript. M.L. takes responsibility for the integrity of the work as a whole, from inception to published article. This investigation was partly supported with funding from the National Center for Research Resources and the National Center for Advancing Translational Sciences, National Institutes of Health (grant 8UL1TR000105 [formerly UL1RR025764]). The authors report no conflicts of interest.
Pneumonia is a common clinical syndrome with well‐described epidemiology and microbiology. Aspiration pneumonia comprises 5% to 15% of patients with pneumonia acquired outside of the hospital,[1] but is less well characterized despite being a major syndrome of pneumonia in the elderly.[2, 3] Difficulties in studying aspiration pneumonia include the lack of a sensitive and specific marker for aspiration as well as the potential overlap between aspiration pneumonia and other forms of pneumonia.[4, 5, 6] Additionally, clinicians have difficulty distinguishing between aspiration pneumonia, which develops after the aspiration of oropharyngeal contents, and aspiration pneumonitis, wherein inhalation of gastric contents causes inflammation without the subsequent development of bacterial infection.[7, 8] Central to the study of aspiration pneumonia is whether it should exist as its own entity, or if aspiration is really a designation used for pneumonia in an older patient with greater comorbidities. The ability to clearly understand how a clinician diagnoses aspiration pneumonia, and whether that method has face validity with expert definitions may allow for improved future research, improved generalizability of current or past research, and possibly better clinical care.
Several validated mortality prediction models exist for community‐acquired pneumonia (CAP) using a variety of clinical predictors, but their performance in patients with aspiration pneumonia is less well characterized. Most studies validating pneumonia severity scoring systems excluded aspiration pneumonia from their study population.[9, 10, 11] Severity scoring systems for CAP may not accurately predict disease severity in patients with aspiration pneumonia. The CURB‐65[9] (confusion, uremia, respiratory rate, blood pressure, age 65 years) and the eCURB[12] scoring systems are poor predictors of mortality in patients with aspiration pneumonia, perhaps because they do not account for patient comorbidities.[13] The pneumonia severity index (PSI)[10] might predict mortality better than CURB‐65 in the aspiration population due to the inclusion of comorbidities.
Previous studies have demonstrated that patients with aspiration pneumonia are older and have greater disease severity and more comorbidities.[13, 14, 15] These single‐center studies also demonstrated greater mortality, more frequent admission to an intensive care unit (ICU), and longer hospital lengths of stay in patients with aspiration pneumonia. These studies identified aspiration pneumonia by the presence of a risk factor for aspiration[15] or by physician billing codes.[13] In practice, however, the bedside clinician diagnoses a patient as having aspiration pneumonia, but the logic is likely vague and inconsistent. Despite the potential for variability with individual judgment, an aggregate estimation from independent judgments may perform better than individual judgments.[16] Because there is no gold standard for defining aspiration pneumonia, all previous research has been limited to definitions created by investigators. This multicenter study seeks to determine what clinical characteristics lead physicians to diagnose a patient as having aspiration pneumonia, and whether or not the clinician‐derived diagnosis is distinct and clinically useful.
Our objectives were to: (1) identify covariates associated with bedside clinicians diagnosing a pneumonia patient as having aspiration pneumonia; (2) compare aspiration pneumonia and nonaspiration pneumonia in regard to disease severity, patient demographics, comorbidities, and clinical outcomes; and (3) measure the performance of the PSI in aspiration pneumonia versus nonaspiration pneumonia.
PATIENTS AND METHODS
Study Design and Setting
We performed a secondary analysis of the Community‐Acquired Pneumonia Organization (CAPO) database, which contains retrospectively collected data from 71 hospitals in 16 countries between June 2001 and December 2012. In each participating center, primary investigators selected nonconsecutive, adult hospitalized patients diagnosed with CAP. To decrease systematic selection biases, the selection of patients with CAP for enrollment in the trial was based on the date of hospital admission. Each investigator completed a case report form that was transferred via the internet to the CAPO study center at the University of Louisville (Louisville, KY). A sample of the data collection form is available at the study website (
Inclusion and Exclusion Criteria
Patients 18 years of age and satisfying criteria for CAP were included in this study. A diagnosis of CAP required a new pulmonary infiltrate at time of hospitalization, and at least 1 of the following: new or increased cough; leukocytosis; leukopenia, or left shift pattern on white blood cell count; and temperature >37.8C or <35.6 C. We excluded patients with pneumonia attributed to mycobacterial or fungal infection, and patients infected with human immunodeficiency virus, as we believed these types of pneumonia differ fundamentally from typical CAP.
Patient Variables
Patient variables included presence of aspiration pneumonia, laboratory data, comorbidities, and measures of disease severity, including the PSI. The clinician made a clinical diagnosis of the presence or absence of aspiration for each patient by marking a box on the case report form. Outcomes included in‐hospital mortality, hospital length of stay up to 14 days, and time to clinical stability up to 8 days. All variables were obtained directly from the case report form. In accordance with previously published definitions, we defined clinical stability as the day the following criteria were all met: improved clinical signs (improved cough and shortness of breath), lack of fever for >8 hours, improving leukocytosis (decreased at least 10% from the previous day), and tolerating oral intake.[17, 18]
Statistical Analysis
Baseline characteristics of patients with aspiration and nonaspiration CAP were compared using 2 or Fisher exact tests for categorical variables and the Mann‐Whitney U test for continuous variables.
To determine which patient variables were important in the physician diagnosis of aspiration pneumonia, we performed logistic regression with initial covariates comprising the demographic, comorbidity, and disease severity measurements listed in Table 1. We included interactions between cerebrovascular disease and age, nursing home status, and confusion to improve model fit. We centered all variables (including binary indicators) according to the method outlined by Kraemer and Blasey to improve interpretation of the main effects.[19]
| Aspiration Pneumonia, N=451 | Nonaspiration Pneumonia, N=4,734 | P Value | |
|---|---|---|---|
|
|||
| Demographics | |||
| Age, y | 79 (6587) | 69 (5380) | <0.001 |
| % Male | 59% | 60% | 0.58 |
| Nursing home residence | 25% | 5% | <0.001 |
| Recent (30 days) antibiotic use | 21% | 16% | 0.017 |
| Comorbidities | |||
| Cerebrovascular disease | 35% | 14% | <0.001 |
| Chronic obstructive pulmonary disease | 25% | 27% | 0.62 |
| Congestive heart failure | 23% | 19% | 0.027 |
| Diabetes | 18% | 18% | 0.85 |
| Cancer | 12% | 10% | 0.12 |
| Renal disease | 10% | 11% | 0.53 |
| Liver disease | 6% | 5% | 0.29 |
| Disease severity | |||
| Pneumonia severity index | 123 (99153) | 92 (68117) | <0.001 |
| Confusion | 49% | 12% | <0.001 |
| PaO2 <60 mm Hg | 43% | 33% | <0.001 |
| BUN >30 g/dL | 42% | 23% | <0.001 |
| Multilobar pneumonia | 34% | 28% | 0.003 |
| Pleural effusion | 25% | 21% | 0.07 |
| Respiratory rate >30 breaths/minute | 21% | 20% | 0.95 |
| pH <7.35 | 13% | 5% | <0.001 |
| Hematocrit <30% | 11% | 6% | 0.001 |
| Temperature >37.8C or <35.6C | 9% | 7% | 0.30 |
| Systolic blood pressure <90 mm Hg | 8% | 9% | 0.003 |
| Sodium <130 mEq/L | 8% | 6% | 0.08 |
| Heart rate >125 beats/minute | 8% | 5% | 0.71 |
| Glucose >250 mg/dL | 6% | 7% | 0.06 |
| Cavitary lesion | 0% | 0% | 0.67 |
| Clinical outcomes | |||
| In‐hospital mortality | 23% | 9% | <0.001 |
| Intensive care unit admission | 19% | 13% | 0.002 |
| Hospital length of stay, d | 9 (515) | 7 (412) | <0.001 |
| Time to clinical stability, d | 8 (48) | 4 (38) | <0.001 |
To determine if aspiration pneumonia had worse clinical outcomes compared to nonaspiration pneumonia, multiple methods were used. To compare the differences between the 2 groups with respect to time to clinical stability and length of hospital stay, we constructed Kaplan‐Meier survival curves and Cox proportional hazards regression models. The log‐rank test was used to determine statistical differences between the Kaplan‐Meier survival curves. To compare the impact of aspiration on mortality in patients with CAP, we conducted a propensity scorematched analysis. We chose propensity score matching over traditional logistic regression to balance variables among groups and to avoid the potential for overfit and multicollinearity. We considered a variable balanced after matching if its standardized difference was <10. All variables in the propensity scorematched analysis were balanced.
Although our dataset contained minimal missing data, we imputed any missing values to maintain the full study population in the creation of the propensity score. Missing data were imputed using the aregImpute function of the hmisc package of R (The R Foundation for Statistical Computing, Vienna, Austria).[20, 21] We built the propensity score model using a variable selection algorithm described by Bursac et al.[22] Our model included variables for region (United States/Canada, Europe, Asia/Africa or Latin America) and the variables listed in Table 1, with the exception of the PSI and the 4 clinical outcomes. Given that previous analyses accounting for clustering by physician did not substantially affect our results,[23] our model did not include physician‐level variables and did not account for the clustering effects of physicians. Using the propensity scores generated from this model, we matched a case of aspiration CAP with a case of nonaspiration CAP.[24] We then constructed a general linear model using the matched dataset to obtain the magnitude of effect of aspiration on mortality.
We used receiver operating characteristic curves to define the diagnostic accuracy of the pneumonia severity index for the prediction of mortality among patients with aspiration pneumonia and those with nonaspiration pneumonia. SAS version 9.3 (SAS Institute, Cary, NC) and R version 2.15.3 (The R Foundation for Statistical Computing) were used for all analyses. P values of 0.05 were considered statistically significant in all analyses.
RESULTS
Our initial query, after exclusion criteria, yielded a study population of 5185 patients (Figure 1). We compared 451 patients diagnosed with aspiration pneumonia to 4734 with CAP (Figure 1). Patient characteristics are summarized in Table 1. Patients with aspiration pneumonia were older, more likely to live in a nursing home, had greater disease severity, and were more likely to be admitted to an ICU. Patients with aspiration pneumonia had longer adjusted hospital lengths of stay and took more days to achieve clinical stability than patients with nonaspiration pneumonia (Figure 2). After adjusting for all variables in Table 1, the Cox proportional hazards models demonstrated that aspiration pneumonia was associated with ongoing hospitalization (hazard ratio [HR] for discharge: 0.77, 95% confidence interval [CI]: 0.65‐0.91, P=0.002) and clinical instability (HR for attaining clinical stability: 0.72, 95% CI: 0.61‐0.84, P<0.001). Patients with aspiration pneumonia presented with greater disease severity than those with nonaspiration pneumonia. Although there was no difference between groups in regard to temperature, respiratory rate, hyponatremia, or presence of pleural effusions or cavitary lesions, all other measured indices of disease severity were worse in patients with aspiration pneumonia. Patients with aspiration pneumonia were more likely to have cerebrovascular disease than those with nonaspiration pneumonia. Aspiration pneumonia patients also had increased prevalence of congestive heart failure. There was no appreciable difference between groups among other measured comorbidities.
The patient characteristics most associated with a physician diagnosis of aspiration pneumonia, identified using logistic regression, were confusion, residence in nursing home, and presence of cerebrovascular disease (odds ratio [OR]: of 4.4, 2.9, and 2.3, respectively), whereas renal disease was associated with decreased physician diagnosis of aspiration pneumonia over nonaspiration pneumonia (OR: 0.58) (Table 2).
| Covariate | Odds Ratio | 95% Confidence Intervals | P Value |
|---|---|---|---|
|
|||
| Demographics | |||
| Age, y | 1.00 | 0.991.01 | 0.948 |
| Male | 1.20 | 0.941.54 | 0.148 |
| Nursing home residence | 2.93 | 2.134.00 | <0.001 |
| Comorbidities | |||
| Cerebrovascular disease | 2.26 | 1.533.32 | <0.001 |
| Renal disease | 0.58 | 0.390.85 | 0.006 |
| Disease severity | |||
| Confusion | 4.41 | 3.405.72 | <0.001 |
| Hematocrit <30% | 1.59 | 1.062.33 | 0.020 |
| pH <7.35 | 1.67 | 1.102.47 | 0.013 |
| Temperature >37.8C or <35.6C | 1.60 | 1.072.35 | 0.019 |
| Multilobar pneumonia | 1.29 | 1.001.65 | 0.047 |
| Interaction terms | |||
| Age * cerebrovascular disease | 0.98 | 0.960.99 | 0.011 |
| Nursing home * cerebrovascular disease | 0.51 | 0.270.96 | 0.037 |
| Confusion * cerebrovascular disease | 0.70 | 0.421.17 | 0.175 |
Observed in‐patient mortality of aspiration pneumonia was 23%. This mortality was considerably higher than a mean PSI score of 123 would predict (class IV risk group, with expected 30‐day mortality of 8%9%[25]). The PSI score's ability to predict inpatient mortality in patients with aspiration pneumonia was moderate, with an area under the curve (AUC) of 0.71. This was similar to its performance in patients with nonaspiration pneumonia (AUC of 0.75) (Figure 3). These values are lower than the AUC of 0.81 for the PSI in predicting mortality derived from a meta‐analysis of 31 other studies.[26]
Our regression model after propensity score matching demonstrated that aspiration pneumonia independently confers a 2.3‐fold increased odds for inpatient mortality (95% CI: 1.56‐3.45, P<0.001).
DISCUSSION
Pneumonia patients with confusion, nursing home residence, or cerebrovascular disease are more likely to be diagnosed with aspiration pneumonia by clinicians. Although this is unsurprising, it is notable that these patients are more than twice as likely to die in the inpatient setting, even after accounting for age, comorbidities, and disease severity. These findings are similar to three previously published studies comparing aspiration and nonaspiration pneumonia at single institutions, albeit using different aspiration pneumonia definitions.[13, 14, 15] This study is the first large, multicenter, multinational study to demonstrate these findings.
Central to the interpretation of our results is the method of diagnosing aspiration versus nonaspiration. A bottom‐up method that relies on a clinician to check a box for aspiration may appear poorly reproducible. Because there is no diagnostic gold standard, clinicians may use different criteria to diagnose aspiration, creating potential for idiosyncratic noise. The strength of the wisdom of the crowd method used in this study is that an aggregate estimation from independent judgments may reduce the noise from individual judgments.[16] Although clinicians may vary in why they diagnose a particular patient as having aspiration pneumonia, it appears that the overwhelming reason for diagnosing a patient as having aspiration pneumonia is the presence of confusion, followed by previous nursing home residence or cerebrovascular disease. This finding has some face validity when compared with studies using an investigator definition, as altered mental status, chronic debility, and cerebrovascular disease are either prominent features of the definition of aspiration pneumonia[8] or frequently observed in patients with aspiration pneumonia.[13, 15] The distribution of cerebrovascular disease among our study's aspiration and nonaspiration pneumonia patients was similar to studies that used formal criteria in their definitions.[13, 15] Although nursing home residence was more likely in aspiration pneumonia patients, the majority of aspiration pneumonia patients were residing in the community, suggesting that aspiration is not simply a surrogate for healthcare‐associated pneumonia. Although patients with aspiration pneumonia are typically older than their nonaspiration counterparts, it appears that age is not a key determinant in the diagnosis of aspiration. With aspiration pneumonia, confusion, nursing home residence, and the presence of cerebrovascular disease are the greatest contributors in the clinical diagnosis, more than age.
Our data demonstrate that aspiration pneumonia confers increased odds for mortality, even after adjustment for age, disease severity, and comorbidities. These data suggest that aspiration pneumonia is a distinct entity from nonaspiration pneumonia, and that this disease is worse than nonaspiration CAP. If aspiration pneumonia is distinct from nonaspiration pneumonia, some unrecognized host factor other than age, disease severity, or the captured comorbidities decreases survival in aspiration pneumonia patients. However, it is also possible that aspiration pneumonia is merely a clinical designation for one end of the pneumonia spectrum, and we and others have failed to completely account for all measures of disease severity or all measures of comorbidities. Examples of unmeasured comorbidities would include presence of oropharyngeal dysphagia, which is not assessed in the database but could have a significant effect on clinical diagnosis. Unmeasured covariates can include measures beyond that of disease severity or comorbidity, such as the presence of a do not resuscitate (DNR) order, which could have a significant confounding effect on the observed association. A previous, single‐center study demonstrated that increased 30‐day mortality in aspiration pneumonia was mostly attributable to greater disease severity and comorbidities, although aspiration pneumonia independently conferred greater risk for adverse long‐term outcomes.[15] We propose that aspiration pneumonia represents a clinically distinct entity from nonaspiration pneumonia. Patients with chronic aspiration are often chronically malnourished and may have different oral flora than patients without chronic aspiration.[27, 28] Chronic aspiration has been associated with granulomatous reaction, organizing pneumonia, diffuse alveolar damage, and chronic bronchiolitis.[29] Chronic aspiration may elicit changes in the host physiology, and may render the host more susceptible to the development of secondary bacterial infection with morbid consequences.
The ability of the PSI to predict inpatient mortality was moderate (AUC only 0.7), with no significant additional discrimination between the aspiration and nonaspiration pneumonia groups. Although the PSI had moderate ability to predict inpatient mortality, the observed mortality was considerably higher than predicted. It is possible that the PSI incompletely captures clinically relevant comorbidities (eg, malnutrition). Further study to improve mortality prediction of aspiration pneumonia patients could employ sensitivity analysis to determine optimal thresholds and weighting of the PSI components.
Patients with aspiration pneumonia had longer hospital lengths of stay and took longer to achieve clinical stability than their nonaspiration counterparts. Time to clinical stability has been associated with increased posthospitalization mortality and is associated with time to switch from intravenous to oral antibiotics.[17] Although some component of hospital length‐of‐stay is subject to local practice patterns, time to clinical stability has explicit criteria for clinical improvement and failure, and therefore is less likely to be affected by local practice patterns.
We noted a relatively high (16%21%) incidence of prior antibiotic use among patients in this database. Analysis of antibiotic prescription patterns was limited, given the several different countries from which the database draws its cases. Although we used accepted criteria to define CAP cases, it is possible that this population may have a higher rate of resistant or uncommon pathogens than other studies of CAP that have populations with lower incidence of prior antibiotic use. Although not assessed, we suspect a significant component of the prior antibiotic use represented outpatient pneumonia treatment during the few days prior to visiting the hospital.
This study has several limitations, of which the most important may be that we used clinical determination for defining presence of aspiration pneumonia. This method is susceptible to the subjective perceptions of the treating clinician. We did not account for the effect of individual physicians in our model, although we did adjust for regional differences. The retrospective identification of patients allows for the possibility of selection bias, and therefore we have not attempted to make inferences regarding the relative incidence of pneumonia, nor did we adjust for temporal trends in diagnosis. The ratio of aspiration pneumonia patients to nonaspiration pneumonia patients may not necessarily reflect that observed in reality. Microbiologic and antibiotic data were unavailable for analysis. This study cannot inform on nonhospitalized patients with aspiration pneumonia, as only hospitalized patients were enrolled. The database identified cases of pneumonia, so it is possible for a patient to enter into the database more than once. Detection of mortality was limited to the inpatient setting rather than a set interval of 30 days. Inpatient mortality depends on length‐of‐stay patterns that may bias the mortality endpoint.[30] Also not assessed was the presence of a DNR order. It is possible that an older patient with greater comorbidities and disease severity may have care intentionally limited or withdrawn early by the family or clinicians.
Strengths of the study include its size and its multicenter, multinational population. The CAPO database is a large and well‐described population of patients with CAP.[17, 31] These attributes, as well as the clinician‐determined diagnosis, increase the generalizability of the study compared to a single‐center, single‐country study that employs investigator‐defined criteria.
CONCLUSION
Pneumonia patients with confusion, who are nursing home residence, and have cerebrovascular disease are more likely to be diagnosed with aspiration pneumonia by clinicians. Our clinician‐diagnosed cohort appears similar to those derived using an investigator definition. Patients with aspiration pneumonia are older, and have greater disease severity and more comorbidities than patients with nonaspiration pneumonia. They have greater mortality than their PSI score class would predict. Even after accounting for age, disease severity, and comorbidities, the presence of aspiration pneumonia independently conferred a greater than 2‐fold increase in inpatient mortality. These findings together suggest that aspiration pneumonia should be considered a distinct entity from typical pneumonia, and that additional research should be done in this field.
ACKNOWLEDGMENTS
Disclosures: M.J.L. contributed to the study design, data analysis, statistical analysis, and writing of the manuscript. P.P. contributed to the study design and revision of the manuscript for important intellectual content. T.W. and E.W. contributed to the study design, statistical analysis, and revision of the manuscript for important intellectual content. J.A.R. and N.C.D. contributed to the study design and revision of the manuscript for important intellectual content. All authors read and approved the final manuscript. M.L. takes responsibility for the integrity of the work as a whole, from inception to published article. This investigation was partly supported with funding from the National Center for Research Resources and the National Center for Advancing Translational Sciences, National Institutes of Health (grant 8UL1TR000105 [formerly UL1RR025764]). The authors report no conflicts of interest.
- , , , et al. Severe community‐acquired pneumonia. Epidemiology and prognostic factors. Am Rev Respir Dis. 1991;144(2):312–318.
- , , . Risk factors for pneumonia in the elderly. Am J Med. 1994;96(4):313–320.
- , . Aspiration pneumonia and dysphagia in the elderly. Chest. 2003;124(1):328–336.
- , , . Pneumonia versus aspiration pneumonitis in nursing home residents: diagnosis and management. J Am Geriatr Soc. 2003;51(1):17–23.
- . Aspiration pneumonia: mixing apples with oranges and tangerines. Crit Care Med. 2004;32(5):1236; author reply 1236–1237.
- , , , , . Epidemiology and impact of aspiration pneumonia in patients undergoing surgery in Maryland, 1999–2000. Crit Care Med. 2003;31(7):1930–1937.
- . Aspiration syndromes: aspiration pneumonia and pneumonitis. Hosp Pract (Minneap). 2010;38(1):35–42.
- . Aspiration pneumonitis and aspiration pneumonia. N Engl J Med. 2001;344(9):665–671.
- , , , et al. Defining community acquired pneumonia severity on presentation to hospital: an international derivation and validation study. Thorax. 2003;58(5):377–382.
- , , , et al. Comparison of a disease‐specific and a generic severity of illness measure for patients with community‐acquired pneumonia. J Gen Intern Med. 1995;10(7):359–368.
- , , , et al. Development and validation of a clinical prediction rule for severe community‐acquired pneumonia. Am J Respir Crit Care Med. 2006;174(11):1249–1256.
- , , , et al. CURB‐65 pneumonia severity assessment adapted for electronic decision support. Chest. 2011;140(1):156–163.
- , , , . Mortality, morbidity, and disease severity of patients with aspiration pneumonia. J Hosp Med. 2013;8(2):83–90.
- , , , , . Pneumonia Severity Index (PSI), CURB‐65, and mortality in hospitalized elderly patients with aspiration pneumonia [in German]. Z Gerontol Geriatr. 2011;44(4):229–234.
- , , , , . Risk factors for aspiration in community‐acquired pneumonia: analysis of a hospitalized UK cohort. Am J Med. 2013;126(11):995–1001.
- , , , . The wisdom of the crowd in combinatorial problems. Cogn Sci. 2012;36(3):452–470.
- , , , et al. Association between time to clinical stability and outcomes after discharge in hospitalized patients with community‐acquired pneumonia. Chest. 2011;140(2):482–488.
- . Clinical stability and switch therapy in hospitalised patients with community‐acquired pneumonia: are we there yet? Eur Respir J. 2013;41(1):5–6.
- , . Centring in regression analyses: a strategy to prevent errors in statistical inference. Int J Methods Psychiatr Res. 2004;13(3):141–151.
- . Hmisc: Harrell miscellaneous. Available at: http://CRAN.R‐project.org/package=Hmisc. Published Sept 12, 2014. Last accessed Oct 27, 2014.
- , . Multiple imputation for the fatal accident reporting system. J R Stat Soc Ser C Appl Stat. 1991;40(1):13–29.
- , , , . Purposeful selection of variables in logistic regression. Source Code Biol Med. 2008;3:17.
- , , , , ; CAPO authors. Mortality differences among hospitalized patients with community‐acquired pneumonia in three world regions: results from the Community‐Acquired Pneumonia Organization (CAPO) International Cohort Study. Respir Med. 2013;107(7):1101–1111.
- . Reducing bias in a propensity score matched‐pair sample using greedy matching techniques. In: Proceedings of the 26th Annual SAS Users Group International Conference. Cary, NC: SAS Institute Inc.; 2001:214–226. Available at: http://www2.sas.com/proceedings/sugi26/p214–26.pdf. Last accessed Oct 27, 2014.
- , , , et al. A prediction rule to identify low‐risk patients with community‐acquired pneumonia. N Engl J Med. 1997;336(4):243–250.
- , , , et al. Severity assessment tools for predicting mortality in hospitalised patients with community‐acquired pneumonia. Systematic review and meta‐analysis. Thorax. 2010;65(10):878–883.
- , , , , , . Prevalence and prognostic implications of dysphagia in elderly patients with pneumonia. Age Ageing. 2010;39(1):39–45.
- , . The association between oral microorgansims and aspiration pneumonia in the institutionalized elderly: review and recommendations. Dysphagia. 2010;25(4):307–322.
- , . Histopathology of aspiration pneumonia not associated with food or other particulate matter: a clinicopathologic study of 10 cases diagnosed on biopsy. Am J Surg Pathol. 2011;35(3):426–431.
- , , , , , . Interpreting hospital mortality data. The role of clinical risk adjustment. JAMA. 1988;260(24):3611–3616.
- , , , . Hospitalization for community‐acquired pneumonia: the pneumonia severity index vs clinical judgment. Chest. 2003;124(1):121–124.
- , , , et al. Severe community‐acquired pneumonia. Epidemiology and prognostic factors. Am Rev Respir Dis. 1991;144(2):312–318.
- , , . Risk factors for pneumonia in the elderly. Am J Med. 1994;96(4):313–320.
- , . Aspiration pneumonia and dysphagia in the elderly. Chest. 2003;124(1):328–336.
- , , . Pneumonia versus aspiration pneumonitis in nursing home residents: diagnosis and management. J Am Geriatr Soc. 2003;51(1):17–23.
- . Aspiration pneumonia: mixing apples with oranges and tangerines. Crit Care Med. 2004;32(5):1236; author reply 1236–1237.
- , , , , . Epidemiology and impact of aspiration pneumonia in patients undergoing surgery in Maryland, 1999–2000. Crit Care Med. 2003;31(7):1930–1937.
- . Aspiration syndromes: aspiration pneumonia and pneumonitis. Hosp Pract (Minneap). 2010;38(1):35–42.
- . Aspiration pneumonitis and aspiration pneumonia. N Engl J Med. 2001;344(9):665–671.
- , , , et al. Defining community acquired pneumonia severity on presentation to hospital: an international derivation and validation study. Thorax. 2003;58(5):377–382.
- , , , et al. Comparison of a disease‐specific and a generic severity of illness measure for patients with community‐acquired pneumonia. J Gen Intern Med. 1995;10(7):359–368.
- , , , et al. Development and validation of a clinical prediction rule for severe community‐acquired pneumonia. Am J Respir Crit Care Med. 2006;174(11):1249–1256.
- , , , et al. CURB‐65 pneumonia severity assessment adapted for electronic decision support. Chest. 2011;140(1):156–163.
- , , , . Mortality, morbidity, and disease severity of patients with aspiration pneumonia. J Hosp Med. 2013;8(2):83–90.
- , , , , . Pneumonia Severity Index (PSI), CURB‐65, and mortality in hospitalized elderly patients with aspiration pneumonia [in German]. Z Gerontol Geriatr. 2011;44(4):229–234.
- , , , , . Risk factors for aspiration in community‐acquired pneumonia: analysis of a hospitalized UK cohort. Am J Med. 2013;126(11):995–1001.
- , , , . The wisdom of the crowd in combinatorial problems. Cogn Sci. 2012;36(3):452–470.
- , , , et al. Association between time to clinical stability and outcomes after discharge in hospitalized patients with community‐acquired pneumonia. Chest. 2011;140(2):482–488.
- . Clinical stability and switch therapy in hospitalised patients with community‐acquired pneumonia: are we there yet? Eur Respir J. 2013;41(1):5–6.
- , . Centring in regression analyses: a strategy to prevent errors in statistical inference. Int J Methods Psychiatr Res. 2004;13(3):141–151.
- . Hmisc: Harrell miscellaneous. Available at: http://CRAN.R‐project.org/package=Hmisc. Published Sept 12, 2014. Last accessed Oct 27, 2014.
- , . Multiple imputation for the fatal accident reporting system. J R Stat Soc Ser C Appl Stat. 1991;40(1):13–29.
- , , , . Purposeful selection of variables in logistic regression. Source Code Biol Med. 2008;3:17.
- , , , , ; CAPO authors. Mortality differences among hospitalized patients with community‐acquired pneumonia in three world regions: results from the Community‐Acquired Pneumonia Organization (CAPO) International Cohort Study. Respir Med. 2013;107(7):1101–1111.
- . Reducing bias in a propensity score matched‐pair sample using greedy matching techniques. In: Proceedings of the 26th Annual SAS Users Group International Conference. Cary, NC: SAS Institute Inc.; 2001:214–226. Available at: http://www2.sas.com/proceedings/sugi26/p214–26.pdf. Last accessed Oct 27, 2014.
- , , , et al. A prediction rule to identify low‐risk patients with community‐acquired pneumonia. N Engl J Med. 1997;336(4):243–250.
- , , , et al. Severity assessment tools for predicting mortality in hospitalised patients with community‐acquired pneumonia. Systematic review and meta‐analysis. Thorax. 2010;65(10):878–883.
- , , , , , . Prevalence and prognostic implications of dysphagia in elderly patients with pneumonia. Age Ageing. 2010;39(1):39–45.
- , . The association between oral microorgansims and aspiration pneumonia in the institutionalized elderly: review and recommendations. Dysphagia. 2010;25(4):307–322.
- , . Histopathology of aspiration pneumonia not associated with food or other particulate matter: a clinicopathologic study of 10 cases diagnosed on biopsy. Am J Surg Pathol. 2011;35(3):426–431.
- , , , , , . Interpreting hospital mortality data. The role of clinical risk adjustment. JAMA. 1988;260(24):3611–3616.
- , , , . Hospitalization for community‐acquired pneumonia: the pneumonia severity index vs clinical judgment. Chest. 2003;124(1):121–124.
© 2014 Society of Hospital Medicine
Caring for women with HIV: Unique needs and challenges
More than 30 years into the human immunodeficiency virus (HIV) epidemic, our understanding of the needs of women living with this virus continues to evolve. In the early years of the epidemic, managing HIV was all about preventing death and treating opportunistic infections. But now it is also about enabling patients to live long, healthy, and productive lives and preventing new HIV infections. In women, these goals can only be achieved by paying careful attention to sex-specific issues.
As a result of longer survival, HIV-infected persons are increasingly developing common health problems that also affect the general population and that require screening, management, and monitoring by primary care providers. Because people infected with HIV are typically seen by both an HIV specialist and a primary care provider, HIV specialists need to be familiar with primary care issues and primary care providers need to be familiar with HIV care recommendations in order to provide optimal care.
AFRICAN AMERICAN WOMEN BEAR A DISPROPORTIONATE BURDEN
In the United States, HIV was first reported in women in 1983 among those who had been steady sexual partners of males with acquired immune deficiency syndrome.1 Although men with HIV still outnumber women, the number of women with HIV has increased rapidly. At the end of 2010 an estimated one in four people with HIV in the United States was female.2
African American women bear a disproportionate burden of the disease (Table 1).3 In 2010, women accounted for an estimated 9,500 (20%) of the approximately 45,000 new infections occurring in the United States. Of these newly infected women, 64% were black, 18% were white, and 15% were Hispanic. Yet blacks make up only about 12% of the US population, whites make up 68%, and Hispanics 14%.
Regardless of race or ethnicity, unprotected heterosexual contact is the most common mode of transmission of HIV in women.2
Although the overall rates of HIV infection in the United States are relatively low, certain areas of the country have rates similar to those in sub-Saharan Africa, where most HIV-infected people reside.4 The HIV Prevention Trials Network found that the incidence of HIV infection in US women living in these “hot spots,” with high rates of poverty and HIV, was 0.32% per year. Compare this with the 2009 estimate of HIV incidence in the general population of US black women of similar age (0.05% per year) and the adult incidence rates in Congo (0.28% per year) and Kenya (0.53% per year).5 To better understand the epidemiology of HIV infection in women and concentrate our prevention efforts, we need to focus on these hot spots.
Misinformation abounds in these hot spots, as does disease. In a survey of residents of the South Side Chicago Housing Authority facilities,6 many were aware that effective antiretroviral therapy existed, but one-fourth thought that there was an effective HIV vaccine, and 13% thought there was a cure.
In the early years, an HIV diagnosis was essentially a death sentence. Samji et al7 estimated that life expectancy of patients who were prescribed antiretroviral therapy in the United States and Canada increased from 36.1 years in 2000–2002 to 51.4 years in 2006–2007, with the greatest increases in those who started with a baseline CD4 count above 350 cells/mm3. Now, a 20-year-old HIV-positive person with a CD4 count greater than 350 cells/mm3 can expect to live into his or her early 70s.
But not all patients achieve these benefits. In 2009, despite major advances in diagnosis and treatment, HIV was the fourth leading cause of death among African American women ages 25 to 44, causing about 800 deaths, or 9% of all deaths in this group.8
TEST ALL, UNLESS THEY OPT OUT
Testing is vital in efforts to prevent and treat HIV infection. In 2006, the US Centers for Disease Control and Prevention (CDC) recommended that everyone between the ages of 13 and 64 be screened for HIV regardless of risk.9
The CDC recommends an opt-out strategy.9 Rather than ask a patient whether he or she wants to be tested for HIV, the provider says something like, “I advise all of my patients to have an HIV test; as long as you have no objection, we will send you to the lab to have it done.” This approach reduces barriers to HIV testing by eliminating pretest counseling and by making HIV testing routine and the standard of care. Separate consent is not required—clinicians just need to document whether the patient has accepted or declined the test.
Testing should be offered at least once and can be done in any health care setting, including primary care offices and clinics, emergency rooms, health departments, and urgent care centers.9 Patients at higher risk (injection drug users and their sex partners; people who exchange sex for money or drugs; sex partners of HIV-infected people; men who have sex with men; and heterosexuals who themselves or whose sex partners have had more than one sex partner since their most recent HIV test) should receive repeat screening annually.
HIV testing should also be offered to all pregnant women at entry into care and again in the third trimester. This strategy is cost-effective even in areas of low prevalence.9 Since 2006, other professional organizations have made HIV testing recommendations as well (Table 2).9–12
A cost-effectiveness analysis suggested that routine opt-out testing is economically justified if the prevalence of HIV is greater than 0.2%.13
HIV-POSITIVE WOMEN NEED ROUTINE GYNECOLOGIC CARE
It is important for women with HIV to receive routine gynecologic care. Women with HIV have gynecologic problems similar to those of all women; however, they may be more vulnerable to certain conditions such as human papillomavirus (HPV) infection, which may be related to HIV disease or associated immunosuppression. In addition, pregnancy and family planning pose special challenges in this group.14
Cervical cancer screening
Effective screening and timely treatment of precancerous cervical lesions are key in preventing cervical cancer in women with or without HIV.
Persistent infection with HPV is necessary for the development of precancerous lesions as well as invasive cervical cancer. Most new cases of HPV infection in the general population resolve spontaneously within 2 years. However, in HIV-infected women, HPV infection is more likely to persist and progress to precancerous lesions of the cervix. This association is strongest in women with more compromised immune function as reflected by low CD4 cell counts and high viral loads.14 Women with HIV have higher rates of infection with high-risk HPV strains and of cervical intraepithelial neoplasia compared with their HIV-negative counterparts.14 The incidence of cervical cancer is five to six times higher in HIV-infected women in the United States than in the general population.15
According to guidelines from the Infectious Diseases Society of America,16 the American College of Obstetricians and Gynecologists,10 the CDC,17 and the American Cancer Society,18 all HIV-infected women should undergo cervical Papanicolaou (Pap) screening upon initiation into care, and this test should be repeated at 6 months and then annually if the results are normal. Patients with abnormalities on the Pap test should undergo colposcopy and, possibly, also biopsy. These abnormalities include atypical squamous cells of unknown significance and higher-grade lesions.16
Nearly one-fourth of HIV-positive women do not receive annual Pap smears despite engagement in care.19 This is unacceptable, because half of the cases of cervical cancer diagnosed in the United States are in women who never received appropriate screening, and an additional 10% are in women who have not been screened in the previous 5 years.19
In HIV-infected women who have had a total hysterectomy, whether to continue Pap testing depends on their history before the surgery. Continued vaginal Pap smear screening is recommended after hysterectomy (including removal of the cervix) in HIV-infected women who have a history of cervical intraepithelial neoplasia grades 2 or 3 or invasive cancer.10,17,20
TREATING HIV IN WOMEN: SPECIAL CONSIDERATIONS
Because it is not yet possible to eradicate the HIV virus, the goals of antiretroviral therapy are to reduce HIV-associated morbidity and mortality, to restore and preserve immune function, to suppress viral load, and to prevent sexual and, in women, perinatal transmission of the virus.21
Antiretroviral therapy is recommended for all HIV-infected patients regardless of the CD4 count, although the strength of recommendation is weaker with higher CD4 counts (Table 3).21 The recommendations for starting antiretroviral therapy and the goals of treatment are the same for men and women. Table 4 summarizes the recommendations for adolescents and adults who are new to treatment.21 For women, additional factors that should be taken into account when considering a regimen include pregnancy potential and whether the drugs chosen for the regimen are considered safe in pregnancy.
Since the early years of the HIV epidemic, researchers have debated whether women attain the same benefits from antiretroviral therapy as men. US Food and Drug Administration investigators performed a meta-analysis of the efficacy outcomes in women in studies of antiretroviral drugs published between 2000 and 2008. They included randomized clinical trials reporting at least 48-week efficacy outcomes, with viral suppression defined as HIV RNA less than 50 copies/mL. The combined database included 40 trials of 16 drugs from 7 drug classes with a total of 20,328 HIV-positive participants. Overall, there were no clinically or statistically significant differences between the sexes in 48-week efficacy outcomes or in rates of trial discontinuation due to adverse events, loss to follow-up, or death.22
Antiretroviral therapy may, however, cause different adverse effects in women than in men. For example:
Nevirapine, a nonnucleoside reverse transcriptase inhibitor, has been associated with the development of a rash and potentially life-threatening hepatotoxicity, more commonly in women than in men and at lower CD4 counts in women. This resulted in recommendations21 to avoid starting a nevirapine-containing regimen in women with CD4 counts greater than 250 cells/mm3 and in men with CD4 counts greater than 400 cells/mm3.
Ritonavir has been observed to cause a higher incidence of nausea and vomiting in women and a higher incidence of diarrhea in men. These are thought to be due to differences between men and women in weight and pharmacokinetics.23
PRECONCEPTION COUNSELING FOR HIV-POSITIVE WOMEN
Preconception counseling is an essential component of both primary and preventive care and should be considered the standard of care for all women of reproductive age who have HIV.24 Health care providers who fully understand the impact of HIV infection and associated comorbidities upon a woman’s reproductive health, fertility desires, and family planning needs are better prepared to assist in their patients’ reproductive health decisions.
The first few weeks of pregnancy are the most critical period in fetal development. During this time, a woman should be healthy and avoid any activities or substances that could cause adverse maternal or fetal outcomes. However, most patients present for prenatal care after this critical time period—thus the need for preconception counseling. Both the Infectious Diseases Society of America and the HIV Medicine Association recommend that all HIV-infected women of childbearing age be asked about their pregnancy plans and desires at the start of care and routinely thereafter.16
The goals of preconception care in women with HIV are to prevent unintended pregnancy, optimize maternal health before pregnancy, optimize pregnancy outcomes for mother and fetus, prevent perinatal HIV transmission, and prevent HIV transmission to an HIV-negative partner when trying to conceive.24
Goal 1: Prevent unintended pregnancy
Nearly half of all pregnancies in the United States are unintended.25 Moreover, the Women’s Interagency HIV Study26 showed that women with HIV are underusing effective contraception. In the Medical Monitoring Project, 85% of the women who had been pregnant since being diagnosed with HIV said that at least one pregnancy was unplanned.27
The consequences of unintended and unplanned pregnancies are serious and add significant burden to women, men, and families. Women who do not wish to become pregnant should be advised to use an effective method of contraception.
Contraception
Contraception use varies worldwide. Factors affecting its use include the methods available, patient choice, current health conditions, religious beliefs, perception of method effectiveness, and side effects.24
The Women’s Interagency HIV Study evaluated trends in contraception use from 1998 to 2010. Condoms were the most common form of contraception, and their use changed little over time. Fewer than 15% of women with HIV used no contraception. The use of long-acting reversible contraception, including injectable progestins, implants, and intrauterine devices, which minimize the need for user adherence, increased among HIV-negative women but not among HIV-positive women.28
The World Health Organization states that all available methods are safe for women with HIV except for spermicides with or without a diaphragm, as there is evidence linking the use of spermicides to an increased risk of HIV transmission (Table 5).29
Some antiretroviral drugs may reduce the effectiveness of some contraceptives (Table 6); however, recommendations are based on pharmacokinetic studies, not on outcome studies. Condoms should be recommended not only to protect against pregnancy, but also to protect against sexually transmitted infections.
Goal 2: Optimize maternal health before pregnancy
Maternal health should be optimized before conceiving to reduce the risk of pregnancy-related morbidities and poor birth outcomes. This includes screening for other infections and ensuring that other comorbidities, such as hypertension, diabetes, substance abuse, and mental illness, are well managed with medications that are safe to use in pregnancy (Table 7).
Goal 3: Prevent perinatal HIV transmission
Educating the patient about perinatal transmission is a fundamental component of preconception counseling. Topics that need to be addressed are transmission risk and methods to reduce the risk, including not breastfeeding after delivery.
Goal 4: Prevent HIV transmission to an uninfected partner when trying to conceive
HIV-discordant couples who desire pregnancy should receive appropriate counseling about methods to minimize risk of transmission to the uninfected partner while trying to conceive. There are a number of effective methods and techniques, which are beyond the scope of this review. Key components of all methods are to screen for and treat sexually transmitted infections in both partners and to use effective antiretroviral therapy and attain maximal viral suppression in the HIV-positive partner.
Antiretroviral therapy for the HIV-infected partner significantly reduced the risk of HIV transmission by 96% in the HIV Prevention Trials Network 052 trial.30 Of note: this reduction was the result of both risk-reduction counseling and antiretroviral therapy. This was the first randomized clinical trial to demonstrate that antiretroviral therapy in those with some preserved immune function (CD4 counts 350–500 cells/mm3) in conjunction with risk-reduction counseling can reduce HIV transmission to an uninfected partner.
Vaginal insemination without intercourse is another option for female-positive couples. The man ejaculates into a condom without spermicide, and the contents are introduced with a non-needle syringe or turkey baster. This can be done at home and confers no risk to the uninfected male partner.31 Chances of pregnancy can be maximized by insemination during the most fertile days of the menstrual cycle.
Preexposure prophylaxis combined with timed intercourse. In a study in Switzerland, the infected male partner was given antiretroviral therapy to suppress his viral load to less than 50 copies/mL for at least 6 months, and luteinizing hormone was measured every day in the urine of the noninfected female partner. When the urinary luteinizing hormone level reached a peak, the woman received a dose of tenofovir in the morning, the couple had unprotected intercourse, and the woman took a second dose the next morning. In 53 cases, none of the female partners seroconverted for HIV.32
Health care providers need to document and update the relationship status, partner HIV status, and fertility desires of their HIV patients, both men and women, on a regular basis. Patient education should include awareness of referrals and options to help safely conceive when desired and achieve effective contraception when not.33
WHEN HIV-POSITIVE WOMEN BECOME PREGNANT
Screening for HIV during pregnancy
The CDC recommends prenatal screening for HIV in the first trimester or at entry into prenatal care. A repeat HIV test should be offered in the third trimester for women at risk of acquiring HIV, for women who have signs or symptoms of early HIV infection, in health care settings where prenatal testing yields at least 1 case of HIV infection per 1,000 women screened, and in areas of high HIV incidence. If women present to labor and delivery with unknown HIV status, rapid HIV testing should be done.9
If a woman acquires HIV during pregnancy, the infection may not be detected and may be transmitted to the infant at birth. From 2002 to 2006 in New York State, 3,396 HIV-exposed babies were born. Of these, 9 (22%) of 41 infants born to mothers who acquired HIV during pregnancy became infected, compared with 1.8% of those born to mothers who acquired HIV before pregnancy. Maternal acquisition of HIV during pregnancy was documented in only 1.3% of perinatal HIV exposures, but it was associated with 9 (13.8%) of the 65 perinatal transmission cases.34
Providers should be aware of the signs and symptoms of acute HIV infection and should have a low threshold for repeating HIV testing at any time during pregnancy. It has been estimated that 40% to 90% of patients with acute HIV infection experience fever, lymphadenopathy, pharyngitis, skin rash, myalgia, arthralgia, or other symptoms.35 Providers often do not recognize acute HIV infection, however, because the symptoms are similar to those of other common illnesses. Also, some individuals with the condition have no symptoms.
Antiretroviral therapy during pregnancy
In a landmark study, AIDS Clinical Trial Group 076 demonstrated that zidovudine monotherapy given during pregnancy, labor, and delivery and to the newborn reduced the risk of HIV transmission to the infant by 67%, from 25% to 8%.36 Other studies demonstrated that combination therapy further decreased the risk of HIV transmission to 1% to 2%.37
The US Department of Health and Human Services recommends that all HIV-positive women who are pregnant receive effective combination antiretroviral therapy regardless of CD4 count to minimize the risk of mother-to-child transmission.37
The goals of HIV treatment during pregnancy are to maintain the woman’s health, restore her immune system, suppress viral replication, and decrease the risk of perinatal transmission. The preferred antiretroviral therapy for pregnant women differs from that for nonpregnant women and is based on evolving experience and information about safety, efficacy, and tolerability in pregnancy (Table 8). A woman who presents for prenatal care on a suppressive regimen should continue that regimen as long as she can tolerate it because there is a risk of losing virologic control when switching regimens, and this may increase the risk of perinatal transmission.37
Physiologic changes that occur during pregnancy may alter drug disposition, which could potentially lead to decreased drug exposure. Some of the changes include an increase in total body water, decreased protein binding, induction of hepatic metabolic pathways, and increased clearance of drugs eliminated by the kidneys.38 These changes may be associated with incomplete virologic suppression, virologic failure, or development of drug resistance, so altered doses of some antiretroviral drugs or careful monitoring of viral load should be considered, particularly in the second and third trimester.
Delivery
Women who have a viral load greater than 1,000 copies/mL near the end of pregnancy should undergo a cesarean delivery at 38 weeks and, before surgery, should receive intravenous zidovudine to reduce the risk of perinatal transmission. For women with viral loads below the threshold of 1,000 copies/mL, there is no proven added benefit to cesarean delivery, and in this situation it should be performed only for standard obstetric indications. Antiretroviral regimens should be continued during labor.37
HIV IN OLDER ADULTS
By 2015, approximately 50% of people with HIV will be over age 50.39 Unfortunately, older people and their providers often underestimate their risk of acquiring HIV. Many older people are newly single and may engage in sexual activity with new partners. Also, older people may be reluctant to use condoms as the need for contraception is past.40,41
Baseline HIV RNA levels tend to be higher and CD4 cell counts lower in patients diagnosed with HIV at older ages. These observations support previous ones that older HIV-infected patients may have advanced HIV disease at the time of diagnosis, perhaps in part due to delayed testing.42 Other possible factors are limited income, comorbid illness, polypharmacy, and insufficient data on drug interactions in the elderly.41,42
A prompt diagnosis is important for older patients because HIV may accelerate aging, and aging may speed up HIV progression. Studies have shown that aging is associated with more rapid progression to AIDS, particularly among people who are older than 40 at seroconversion.43 Other studies have reported that older patients have better virologic responses to antiretroviral therapy but have a blunted immune response, more AIDS-defining events, and a higher mortality rate than younger patients.42
- Centers for Disease Control and Prevention (CDC). Immunodeficiency among female sexual partners of males with acquired immune deficiency syndrome (AIDS) - New York. MMWR Morb Mortal Wkly Rep 1983; 31:697–698.
- Centers for Disease Control and Prevention (CDC). Estimated HIV incidence in the United States, 2007–2010. HIV Surveillance Supplemental Report 2012; 17( No. 4). www.cdc.gov/hiv/topics/surveillance/resources/reports/#supplemental. Accessed October 3, 2014.
- Centers for Disease Control and Prevention. HIV in the United States: at a glance. www.cdc.gov/hiv/statistics/basics/ataglance.html. Accessed October 3, 2014.
- El-Sadr WM, Mayer KH, Hodder SL. AIDS in America—forgotten but not gone. N Engl J Med 2010; 362:967–970.
- Eshleman SH, Hughes JP, Laeyendecker O, et al. Use of a multifaceted approach to analyze HIV incidence in a cohort study of women in the United States: HIV Prevention Trials Network 064 Study. J Infect Dis 2013; 207:223–231.
- Djokic D, Englund J, Daum R, et al. HIV knowledge and attitudes toward HIV testing of South Side Chicago Housing Authority residents. AIDS Patient Care STDS 2009; 23:23–28.
- Samji H, Cescon A, Hogg RS, et al; North American AIDS Cohort Collaboration on Research and Design (NA-ACCORD) of IeDEA. Closing the gap: increases in life expectancy among treated HIV-positive individuals in the United States and Canada. PLoS One 2013; 8:e81355.
- Centers for Disease Control and Prevention (CDC). HIV/AIDS. HIV mortality (through 2010). www.cdc.gov/hiv/library/slideSets/index.html. Accessed October 3, 2014.
- Branson BM, Handsfield HH, Lampe MA, et al; Centers for Disease Control and Prevention (CDC). Revised recommendations for HIV testing of adults, adolescents, and pregnant women in health-care settings. MMWR Recomm Rep 2006; 55:1–17.
- The American College of Obstetricians and Gynecologists (ACOG). Routine Human Immunodeficiency Virus Screening Committee Opinion Number 596, May 2014. (Replaces Committee Opinion Number 411, August 2008.) www.acog.org/Resources_And_Publications/Committee_Opinions/Committee_on_Gynecologic_Practice/Routine_Human_Immunodeficiency_Virus_Screening. Accessed October 3, 2014.
- US Preventive Services Task Force. Screening for HIV. http://www.uspreventiveservicestaskforce.org/Page/Topic/recommendation-summary/human-immunodeficiency-virus-hiv-infection-screening. Accessed October 3, 2014.
- Institute of Medicine. HIV screening and access to care health care system capacity for increased HIV testing and provision of care. www.iom.edu/Reports/2011/HIV-Screening-and-Access-to-Care-Health-Care-System-Capacity-for-Increased-HIV-Testing-and-Provision-of-Care.aspx. Accessed October 3, 2014.
- Walensky RP, Freedberg KA, Weinstein MC, Paltiel AD. Cost-effectiveness of HIV testing and treatment in the United States. Clin Infect Dis 2007; 45(suppl 4):S248–S254.
- ACOG Committee on Practice Bulletins—Gynecology. ACOG Practice Bulletin No. 117: Gynecologic care for women with human immunodeficiency virus. Obstet Gynecol 2010; 116:1492–1509.
- Centers for Disease Control and Prevention (CDC). Invasive cancer incidence—United States, 2009. MMWR Morb Mortal Wkly Rep 2013; 62:113–118.
- Aberg JA, Gallant JE, Ghanem KG, Emmanuel P, Zingman BS, Horberg MA. Primary care guidelines for the management of persons infected with HIV: 2013 update by the HIV Medicine Association of the Infectious Diseases Society of America. Clin Infect Dis 2014; 58:e1–e34.
- Panel on Opportunistic Infections in HIV-Infected Adults and Adolescents. Guidelines for the prevention and treatment of opportunistic infections in HIV-infected adults and adolescents: recommendations from the Centers for Disease Control and Prevention, the National Institutes of Health, and the HIV Medicine Association of the Infectious Diseases Society of America. http://aidsinfo.nih.gov/contentfiles/lvguidelines/adult_oi.pdf. Accessed October 3, 2014.
- Saslow D, Solomon D, Lawson HW, et al; ACS-ASCCP-ASCP Cervical Cancer Guideline Committee. American Cancer Society, American Society for Colposcopy and Cervical Pathology, and American Society for Clinical Pathology screening guidelines for the prevention and early detection of cervical cancer. CA Cancer J Clin 2012; 62:147–172.
- Oster AM, Sullivan PS, Blair JM. Prevalence of cervical cancer screening of HIV-infected women in the United States. J Acquir Immune Defic Syndr 2009; 51:430–436.
- Paramsothy P, Duerr A, Heilig CM, et al; HIV Epidemiology Research (HER) Study Group. Abnormal vaginal cytology in HIV-infected and at-risk women after hysterectomy. J Acquir Immune Defic Syndr 2004; 35:484–491.
- Panel on Antiretroviral Guidelines for Adults and Adolescents. Guidelines for the use of antiretroviral agents in HIV-1-infected adults and adolescents. Department of Health and Human Services. http://aidsinfo.nih.gov/ContentFiles/AdultandAdolescentGL.pdf. Accessed October 3, 2014.
- Soon GG, Min M, Struble KA, et al. Meta-analysis of gender differences in efficacy outcomes for HIV-positive subjects in randomized controlled clinical trials of antiretroviral therapy (2000–2008). AIDS Patient Care STDS 2012; 26:444–453.
- Clark RA, Squires KE. Gender-specific considerations in the antiretroviral management of HIV-infected women. Expert Rev Anti Infect Ther 2005; 3:213–227.
- Johnson K, Posner SF, Biermann J, et al; CDC/ATSDR Preconception Care Work Group; Select Panel on Preconception Care. Recommendations to improve preconception health and health care—United States. A report of the CDC/ATSDR Preconception Care Work Group and the Select Panel on Preconception Care. MMWR Recomm Rep 2006; 55:1–23.
- Finer LB, Zolna MR. Unintended pregnancy in the United States: incidence and disparities, 2006. Contraception 2011; 84:478–485.
- Massad LS, Evans CT, Wilson TE, et al. Contraceptive use among US women with HIV. J Womens Health (Larchmt) 2007; 16:657–666.
- Sutton MY, Patel R, Frazier EL. Unplanned pregnancies among HIV-infected women in care-United States. J Acquir Immune Defic Syndr 2014; 65:350–358.
- Sun M, Peipert JF, Zhao Q, et al. Trends in contraceptive use among women with human immunodeficiency virus. Obstet Gynecol 2012; 120:783–790.
- World Health Organization (WHO). Medical eligibility criteria for contraceptive use. 4th ed. http://whqlibdoc.who.int/publications/2010/9789241563888_eng.pdf. Accessed October 3, 2014.
- Cohen MS, Chen YQ, McCauley M, et al; HPTN 052 Study Team. Prevention of HIV-1 infection with early antiretroviral therapy. N Engl J Med 2011; 365:493–505.
- Mmeje O, Cohen CR, Cohan D. Evaluating safer conception options for HIV-serodiscordant couples (HIV-infected female/HIV-uninfected male): a closer look at vaginal insemination. Infect Dis Obstet Gynecol 2012; 2012:587–651.
- Vernazza PL, Graf I, Sonnenberg-Schwan U, Geit M, Meurer A. Preexposure prophylaxis and timed intercourse for HIV-discordant couples willing to conceive a child. AIDS 2011; 25:2005–2008.
- Lampe MA, Smith DK, Anderson GJ, Edwards AE, Nesheim SR. Achieving safe conception in HIV-discordant couples: the potential role of oral preexposure prophylaxis (PrEP) in the United States. Am J Obstet Gynecol 2011; 204:488.e1–e8.
- Birkhead GS, Pulver WP, Warren BL, Hackel S, Rodríguez D, Smith L. Acquiring human immunodeficiency virus during pregnancy and mother-to-child transmission in New York: 2002–2006. Obstet Gynecol 2010; 115:1247–1255.
- Yerly S, Hirschel B. Diagnosing acute HIV infection. Expert Rev Anti Infect Ther 2012; 10:31–41.
- Connor EM, Sperling RS, Gelber R, et al. Reduction of maternal-infant transmission of human immunodeficiency virus type 1 with zidovudine treatment. Pediatric AIDS Clinical Trials Group Protocol 076 Study Group. N Engl J Med 1994; 331:1173–1180.
- Panel on Treatment of HIV-Infected Pregnant Women and Prevention of Perinatal Transmission. Recommendations for use of antiretroviral drugs in pregnant HIV-1-infected women for maternal health and interventions to reduce perinatal HIV transmission in the United States. http://aidsinfo.nih.gov/contentfiles/lvguidelines/PerinatalGL.pdf. Accessed October 3, 2014.
- Mirochnick M, Capparelli E. Pharmacokinetics of antiretrovirals in pregnant women. Clin Pharmacokinet 2004; 43:1071–1087.
- Smith GSenate Committee on Aging. HIV over fifty: exploring the new threat. Washington, DC; 2005. http://www.aging.senate.gov/imo/media/doc/5122005.pdf. Accessed October 3, 2014.
- Illa L, Brickman A, Saint-Jean G, et al. Sexual risk behaviors in late middle age and older HIV seropositive adults. AIDS Behav 2008; 12:935–942.
- Luther VP, Wilkin AM. HIV infection in older adults. Clin Geriatr Med 2007; 23:567–583.
- Collaboration of Observational HIV Epidemiological Research Europe (COHERE) Study Group; Sabin CA, Smith CJ, d’Arminio Monforte A, et al. Response to combination antiretroviral therapy: variation by age. AIDS 2008; 22:1463–1473.
- Pezzotti P, Phillips AN, Dorrucci M, et al. Category of exposure to HIV and age in the progression to AIDS: longitudinal study of 1,199 people with known dates of seroconversion. HIV Italian Seroconversion Study Group. BMJ 1996; 313:583–586.
More than 30 years into the human immunodeficiency virus (HIV) epidemic, our understanding of the needs of women living with this virus continues to evolve. In the early years of the epidemic, managing HIV was all about preventing death and treating opportunistic infections. But now it is also about enabling patients to live long, healthy, and productive lives and preventing new HIV infections. In women, these goals can only be achieved by paying careful attention to sex-specific issues.
As a result of longer survival, HIV-infected persons are increasingly developing common health problems that also affect the general population and that require screening, management, and monitoring by primary care providers. Because people infected with HIV are typically seen by both an HIV specialist and a primary care provider, HIV specialists need to be familiar with primary care issues and primary care providers need to be familiar with HIV care recommendations in order to provide optimal care.
AFRICAN AMERICAN WOMEN BEAR A DISPROPORTIONATE BURDEN
In the United States, HIV was first reported in women in 1983 among those who had been steady sexual partners of males with acquired immune deficiency syndrome.1 Although men with HIV still outnumber women, the number of women with HIV has increased rapidly. At the end of 2010 an estimated one in four people with HIV in the United States was female.2
African American women bear a disproportionate burden of the disease (Table 1).3 In 2010, women accounted for an estimated 9,500 (20%) of the approximately 45,000 new infections occurring in the United States. Of these newly infected women, 64% were black, 18% were white, and 15% were Hispanic. Yet blacks make up only about 12% of the US population, whites make up 68%, and Hispanics 14%.
Regardless of race or ethnicity, unprotected heterosexual contact is the most common mode of transmission of HIV in women.2
Although the overall rates of HIV infection in the United States are relatively low, certain areas of the country have rates similar to those in sub-Saharan Africa, where most HIV-infected people reside.4 The HIV Prevention Trials Network found that the incidence of HIV infection in US women living in these “hot spots,” with high rates of poverty and HIV, was 0.32% per year. Compare this with the 2009 estimate of HIV incidence in the general population of US black women of similar age (0.05% per year) and the adult incidence rates in Congo (0.28% per year) and Kenya (0.53% per year).5 To better understand the epidemiology of HIV infection in women and concentrate our prevention efforts, we need to focus on these hot spots.
Misinformation abounds in these hot spots, as does disease. In a survey of residents of the South Side Chicago Housing Authority facilities,6 many were aware that effective antiretroviral therapy existed, but one-fourth thought that there was an effective HIV vaccine, and 13% thought there was a cure.
In the early years, an HIV diagnosis was essentially a death sentence. Samji et al7 estimated that life expectancy of patients who were prescribed antiretroviral therapy in the United States and Canada increased from 36.1 years in 2000–2002 to 51.4 years in 2006–2007, with the greatest increases in those who started with a baseline CD4 count above 350 cells/mm3. Now, a 20-year-old HIV-positive person with a CD4 count greater than 350 cells/mm3 can expect to live into his or her early 70s.
But not all patients achieve these benefits. In 2009, despite major advances in diagnosis and treatment, HIV was the fourth leading cause of death among African American women ages 25 to 44, causing about 800 deaths, or 9% of all deaths in this group.8
TEST ALL, UNLESS THEY OPT OUT
Testing is vital in efforts to prevent and treat HIV infection. In 2006, the US Centers for Disease Control and Prevention (CDC) recommended that everyone between the ages of 13 and 64 be screened for HIV regardless of risk.9
The CDC recommends an opt-out strategy.9 Rather than ask a patient whether he or she wants to be tested for HIV, the provider says something like, “I advise all of my patients to have an HIV test; as long as you have no objection, we will send you to the lab to have it done.” This approach reduces barriers to HIV testing by eliminating pretest counseling and by making HIV testing routine and the standard of care. Separate consent is not required—clinicians just need to document whether the patient has accepted or declined the test.
Testing should be offered at least once and can be done in any health care setting, including primary care offices and clinics, emergency rooms, health departments, and urgent care centers.9 Patients at higher risk (injection drug users and their sex partners; people who exchange sex for money or drugs; sex partners of HIV-infected people; men who have sex with men; and heterosexuals who themselves or whose sex partners have had more than one sex partner since their most recent HIV test) should receive repeat screening annually.
HIV testing should also be offered to all pregnant women at entry into care and again in the third trimester. This strategy is cost-effective even in areas of low prevalence.9 Since 2006, other professional organizations have made HIV testing recommendations as well (Table 2).9–12
A cost-effectiveness analysis suggested that routine opt-out testing is economically justified if the prevalence of HIV is greater than 0.2%.13
HIV-POSITIVE WOMEN NEED ROUTINE GYNECOLOGIC CARE
It is important for women with HIV to receive routine gynecologic care. Women with HIV have gynecologic problems similar to those of all women; however, they may be more vulnerable to certain conditions such as human papillomavirus (HPV) infection, which may be related to HIV disease or associated immunosuppression. In addition, pregnancy and family planning pose special challenges in this group.14
Cervical cancer screening
Effective screening and timely treatment of precancerous cervical lesions are key in preventing cervical cancer in women with or without HIV.
Persistent infection with HPV is necessary for the development of precancerous lesions as well as invasive cervical cancer. Most new cases of HPV infection in the general population resolve spontaneously within 2 years. However, in HIV-infected women, HPV infection is more likely to persist and progress to precancerous lesions of the cervix. This association is strongest in women with more compromised immune function as reflected by low CD4 cell counts and high viral loads.14 Women with HIV have higher rates of infection with high-risk HPV strains and of cervical intraepithelial neoplasia compared with their HIV-negative counterparts.14 The incidence of cervical cancer is five to six times higher in HIV-infected women in the United States than in the general population.15
According to guidelines from the Infectious Diseases Society of America,16 the American College of Obstetricians and Gynecologists,10 the CDC,17 and the American Cancer Society,18 all HIV-infected women should undergo cervical Papanicolaou (Pap) screening upon initiation into care, and this test should be repeated at 6 months and then annually if the results are normal. Patients with abnormalities on the Pap test should undergo colposcopy and, possibly, also biopsy. These abnormalities include atypical squamous cells of unknown significance and higher-grade lesions.16
Nearly one-fourth of HIV-positive women do not receive annual Pap smears despite engagement in care.19 This is unacceptable, because half of the cases of cervical cancer diagnosed in the United States are in women who never received appropriate screening, and an additional 10% are in women who have not been screened in the previous 5 years.19
In HIV-infected women who have had a total hysterectomy, whether to continue Pap testing depends on their history before the surgery. Continued vaginal Pap smear screening is recommended after hysterectomy (including removal of the cervix) in HIV-infected women who have a history of cervical intraepithelial neoplasia grades 2 or 3 or invasive cancer.10,17,20
TREATING HIV IN WOMEN: SPECIAL CONSIDERATIONS
Because it is not yet possible to eradicate the HIV virus, the goals of antiretroviral therapy are to reduce HIV-associated morbidity and mortality, to restore and preserve immune function, to suppress viral load, and to prevent sexual and, in women, perinatal transmission of the virus.21
Antiretroviral therapy is recommended for all HIV-infected patients regardless of the CD4 count, although the strength of recommendation is weaker with higher CD4 counts (Table 3).21 The recommendations for starting antiretroviral therapy and the goals of treatment are the same for men and women. Table 4 summarizes the recommendations for adolescents and adults who are new to treatment.21 For women, additional factors that should be taken into account when considering a regimen include pregnancy potential and whether the drugs chosen for the regimen are considered safe in pregnancy.
Since the early years of the HIV epidemic, researchers have debated whether women attain the same benefits from antiretroviral therapy as men. US Food and Drug Administration investigators performed a meta-analysis of the efficacy outcomes in women in studies of antiretroviral drugs published between 2000 and 2008. They included randomized clinical trials reporting at least 48-week efficacy outcomes, with viral suppression defined as HIV RNA less than 50 copies/mL. The combined database included 40 trials of 16 drugs from 7 drug classes with a total of 20,328 HIV-positive participants. Overall, there were no clinically or statistically significant differences between the sexes in 48-week efficacy outcomes or in rates of trial discontinuation due to adverse events, loss to follow-up, or death.22
Antiretroviral therapy may, however, cause different adverse effects in women than in men. For example:
Nevirapine, a nonnucleoside reverse transcriptase inhibitor, has been associated with the development of a rash and potentially life-threatening hepatotoxicity, more commonly in women than in men and at lower CD4 counts in women. This resulted in recommendations21 to avoid starting a nevirapine-containing regimen in women with CD4 counts greater than 250 cells/mm3 and in men with CD4 counts greater than 400 cells/mm3.
Ritonavir has been observed to cause a higher incidence of nausea and vomiting in women and a higher incidence of diarrhea in men. These are thought to be due to differences between men and women in weight and pharmacokinetics.23
PRECONCEPTION COUNSELING FOR HIV-POSITIVE WOMEN
Preconception counseling is an essential component of both primary and preventive care and should be considered the standard of care for all women of reproductive age who have HIV.24 Health care providers who fully understand the impact of HIV infection and associated comorbidities upon a woman’s reproductive health, fertility desires, and family planning needs are better prepared to assist in their patients’ reproductive health decisions.
The first few weeks of pregnancy are the most critical period in fetal development. During this time, a woman should be healthy and avoid any activities or substances that could cause adverse maternal or fetal outcomes. However, most patients present for prenatal care after this critical time period—thus the need for preconception counseling. Both the Infectious Diseases Society of America and the HIV Medicine Association recommend that all HIV-infected women of childbearing age be asked about their pregnancy plans and desires at the start of care and routinely thereafter.16
The goals of preconception care in women with HIV are to prevent unintended pregnancy, optimize maternal health before pregnancy, optimize pregnancy outcomes for mother and fetus, prevent perinatal HIV transmission, and prevent HIV transmission to an HIV-negative partner when trying to conceive.24
Goal 1: Prevent unintended pregnancy
Nearly half of all pregnancies in the United States are unintended.25 Moreover, the Women’s Interagency HIV Study26 showed that women with HIV are underusing effective contraception. In the Medical Monitoring Project, 85% of the women who had been pregnant since being diagnosed with HIV said that at least one pregnancy was unplanned.27
The consequences of unintended and unplanned pregnancies are serious and add significant burden to women, men, and families. Women who do not wish to become pregnant should be advised to use an effective method of contraception.
Contraception
Contraception use varies worldwide. Factors affecting its use include the methods available, patient choice, current health conditions, religious beliefs, perception of method effectiveness, and side effects.24
The Women’s Interagency HIV Study evaluated trends in contraception use from 1998 to 2010. Condoms were the most common form of contraception, and their use changed little over time. Fewer than 15% of women with HIV used no contraception. The use of long-acting reversible contraception, including injectable progestins, implants, and intrauterine devices, which minimize the need for user adherence, increased among HIV-negative women but not among HIV-positive women.28
The World Health Organization states that all available methods are safe for women with HIV except for spermicides with or without a diaphragm, as there is evidence linking the use of spermicides to an increased risk of HIV transmission (Table 5).29
Some antiretroviral drugs may reduce the effectiveness of some contraceptives (Table 6); however, recommendations are based on pharmacokinetic studies, not on outcome studies. Condoms should be recommended not only to protect against pregnancy, but also to protect against sexually transmitted infections.
Goal 2: Optimize maternal health before pregnancy
Maternal health should be optimized before conceiving to reduce the risk of pregnancy-related morbidities and poor birth outcomes. This includes screening for other infections and ensuring that other comorbidities, such as hypertension, diabetes, substance abuse, and mental illness, are well managed with medications that are safe to use in pregnancy (Table 7).
Goal 3: Prevent perinatal HIV transmission
Educating the patient about perinatal transmission is a fundamental component of preconception counseling. Topics that need to be addressed are transmission risk and methods to reduce the risk, including not breastfeeding after delivery.
Goal 4: Prevent HIV transmission to an uninfected partner when trying to conceive
HIV-discordant couples who desire pregnancy should receive appropriate counseling about methods to minimize risk of transmission to the uninfected partner while trying to conceive. There are a number of effective methods and techniques, which are beyond the scope of this review. Key components of all methods are to screen for and treat sexually transmitted infections in both partners and to use effective antiretroviral therapy and attain maximal viral suppression in the HIV-positive partner.
Antiretroviral therapy for the HIV-infected partner significantly reduced the risk of HIV transmission by 96% in the HIV Prevention Trials Network 052 trial.30 Of note: this reduction was the result of both risk-reduction counseling and antiretroviral therapy. This was the first randomized clinical trial to demonstrate that antiretroviral therapy in those with some preserved immune function (CD4 counts 350–500 cells/mm3) in conjunction with risk-reduction counseling can reduce HIV transmission to an uninfected partner.
Vaginal insemination without intercourse is another option for female-positive couples. The man ejaculates into a condom without spermicide, and the contents are introduced with a non-needle syringe or turkey baster. This can be done at home and confers no risk to the uninfected male partner.31 Chances of pregnancy can be maximized by insemination during the most fertile days of the menstrual cycle.
Preexposure prophylaxis combined with timed intercourse. In a study in Switzerland, the infected male partner was given antiretroviral therapy to suppress his viral load to less than 50 copies/mL for at least 6 months, and luteinizing hormone was measured every day in the urine of the noninfected female partner. When the urinary luteinizing hormone level reached a peak, the woman received a dose of tenofovir in the morning, the couple had unprotected intercourse, and the woman took a second dose the next morning. In 53 cases, none of the female partners seroconverted for HIV.32
Health care providers need to document and update the relationship status, partner HIV status, and fertility desires of their HIV patients, both men and women, on a regular basis. Patient education should include awareness of referrals and options to help safely conceive when desired and achieve effective contraception when not.33
WHEN HIV-POSITIVE WOMEN BECOME PREGNANT
Screening for HIV during pregnancy
The CDC recommends prenatal screening for HIV in the first trimester or at entry into prenatal care. A repeat HIV test should be offered in the third trimester for women at risk of acquiring HIV, for women who have signs or symptoms of early HIV infection, in health care settings where prenatal testing yields at least 1 case of HIV infection per 1,000 women screened, and in areas of high HIV incidence. If women present to labor and delivery with unknown HIV status, rapid HIV testing should be done.9
If a woman acquires HIV during pregnancy, the infection may not be detected and may be transmitted to the infant at birth. From 2002 to 2006 in New York State, 3,396 HIV-exposed babies were born. Of these, 9 (22%) of 41 infants born to mothers who acquired HIV during pregnancy became infected, compared with 1.8% of those born to mothers who acquired HIV before pregnancy. Maternal acquisition of HIV during pregnancy was documented in only 1.3% of perinatal HIV exposures, but it was associated with 9 (13.8%) of the 65 perinatal transmission cases.34
Providers should be aware of the signs and symptoms of acute HIV infection and should have a low threshold for repeating HIV testing at any time during pregnancy. It has been estimated that 40% to 90% of patients with acute HIV infection experience fever, lymphadenopathy, pharyngitis, skin rash, myalgia, arthralgia, or other symptoms.35 Providers often do not recognize acute HIV infection, however, because the symptoms are similar to those of other common illnesses. Also, some individuals with the condition have no symptoms.
Antiretroviral therapy during pregnancy
In a landmark study, AIDS Clinical Trial Group 076 demonstrated that zidovudine monotherapy given during pregnancy, labor, and delivery and to the newborn reduced the risk of HIV transmission to the infant by 67%, from 25% to 8%.36 Other studies demonstrated that combination therapy further decreased the risk of HIV transmission to 1% to 2%.37
The US Department of Health and Human Services recommends that all HIV-positive women who are pregnant receive effective combination antiretroviral therapy regardless of CD4 count to minimize the risk of mother-to-child transmission.37
The goals of HIV treatment during pregnancy are to maintain the woman’s health, restore her immune system, suppress viral replication, and decrease the risk of perinatal transmission. The preferred antiretroviral therapy for pregnant women differs from that for nonpregnant women and is based on evolving experience and information about safety, efficacy, and tolerability in pregnancy (Table 8). A woman who presents for prenatal care on a suppressive regimen should continue that regimen as long as she can tolerate it because there is a risk of losing virologic control when switching regimens, and this may increase the risk of perinatal transmission.37
Physiologic changes that occur during pregnancy may alter drug disposition, which could potentially lead to decreased drug exposure. Some of the changes include an increase in total body water, decreased protein binding, induction of hepatic metabolic pathways, and increased clearance of drugs eliminated by the kidneys.38 These changes may be associated with incomplete virologic suppression, virologic failure, or development of drug resistance, so altered doses of some antiretroviral drugs or careful monitoring of viral load should be considered, particularly in the second and third trimester.
Delivery
Women who have a viral load greater than 1,000 copies/mL near the end of pregnancy should undergo a cesarean delivery at 38 weeks and, before surgery, should receive intravenous zidovudine to reduce the risk of perinatal transmission. For women with viral loads below the threshold of 1,000 copies/mL, there is no proven added benefit to cesarean delivery, and in this situation it should be performed only for standard obstetric indications. Antiretroviral regimens should be continued during labor.37
HIV IN OLDER ADULTS
By 2015, approximately 50% of people with HIV will be over age 50.39 Unfortunately, older people and their providers often underestimate their risk of acquiring HIV. Many older people are newly single and may engage in sexual activity with new partners. Also, older people may be reluctant to use condoms as the need for contraception is past.40,41
Baseline HIV RNA levels tend to be higher and CD4 cell counts lower in patients diagnosed with HIV at older ages. These observations support previous ones that older HIV-infected patients may have advanced HIV disease at the time of diagnosis, perhaps in part due to delayed testing.42 Other possible factors are limited income, comorbid illness, polypharmacy, and insufficient data on drug interactions in the elderly.41,42
A prompt diagnosis is important for older patients because HIV may accelerate aging, and aging may speed up HIV progression. Studies have shown that aging is associated with more rapid progression to AIDS, particularly among people who are older than 40 at seroconversion.43 Other studies have reported that older patients have better virologic responses to antiretroviral therapy but have a blunted immune response, more AIDS-defining events, and a higher mortality rate than younger patients.42
More than 30 years into the human immunodeficiency virus (HIV) epidemic, our understanding of the needs of women living with this virus continues to evolve. In the early years of the epidemic, managing HIV was all about preventing death and treating opportunistic infections. But now it is also about enabling patients to live long, healthy, and productive lives and preventing new HIV infections. In women, these goals can only be achieved by paying careful attention to sex-specific issues.
As a result of longer survival, HIV-infected persons are increasingly developing common health problems that also affect the general population and that require screening, management, and monitoring by primary care providers. Because people infected with HIV are typically seen by both an HIV specialist and a primary care provider, HIV specialists need to be familiar with primary care issues and primary care providers need to be familiar with HIV care recommendations in order to provide optimal care.
AFRICAN AMERICAN WOMEN BEAR A DISPROPORTIONATE BURDEN
In the United States, HIV was first reported in women in 1983 among those who had been steady sexual partners of males with acquired immune deficiency syndrome.1 Although men with HIV still outnumber women, the number of women with HIV has increased rapidly. At the end of 2010 an estimated one in four people with HIV in the United States was female.2
African American women bear a disproportionate burden of the disease (Table 1).3 In 2010, women accounted for an estimated 9,500 (20%) of the approximately 45,000 new infections occurring in the United States. Of these newly infected women, 64% were black, 18% were white, and 15% were Hispanic. Yet blacks make up only about 12% of the US population, whites make up 68%, and Hispanics 14%.
Regardless of race or ethnicity, unprotected heterosexual contact is the most common mode of transmission of HIV in women.2
Although the overall rates of HIV infection in the United States are relatively low, certain areas of the country have rates similar to those in sub-Saharan Africa, where most HIV-infected people reside.4 The HIV Prevention Trials Network found that the incidence of HIV infection in US women living in these “hot spots,” with high rates of poverty and HIV, was 0.32% per year. Compare this with the 2009 estimate of HIV incidence in the general population of US black women of similar age (0.05% per year) and the adult incidence rates in Congo (0.28% per year) and Kenya (0.53% per year).5 To better understand the epidemiology of HIV infection in women and concentrate our prevention efforts, we need to focus on these hot spots.
Misinformation abounds in these hot spots, as does disease. In a survey of residents of the South Side Chicago Housing Authority facilities,6 many were aware that effective antiretroviral therapy existed, but one-fourth thought that there was an effective HIV vaccine, and 13% thought there was a cure.
In the early years, an HIV diagnosis was essentially a death sentence. Samji et al7 estimated that life expectancy of patients who were prescribed antiretroviral therapy in the United States and Canada increased from 36.1 years in 2000–2002 to 51.4 years in 2006–2007, with the greatest increases in those who started with a baseline CD4 count above 350 cells/mm3. Now, a 20-year-old HIV-positive person with a CD4 count greater than 350 cells/mm3 can expect to live into his or her early 70s.
But not all patients achieve these benefits. In 2009, despite major advances in diagnosis and treatment, HIV was the fourth leading cause of death among African American women ages 25 to 44, causing about 800 deaths, or 9% of all deaths in this group.8
TEST ALL, UNLESS THEY OPT OUT
Testing is vital in efforts to prevent and treat HIV infection. In 2006, the US Centers for Disease Control and Prevention (CDC) recommended that everyone between the ages of 13 and 64 be screened for HIV regardless of risk.9
The CDC recommends an opt-out strategy.9 Rather than ask a patient whether he or she wants to be tested for HIV, the provider says something like, “I advise all of my patients to have an HIV test; as long as you have no objection, we will send you to the lab to have it done.” This approach reduces barriers to HIV testing by eliminating pretest counseling and by making HIV testing routine and the standard of care. Separate consent is not required—clinicians just need to document whether the patient has accepted or declined the test.
Testing should be offered at least once and can be done in any health care setting, including primary care offices and clinics, emergency rooms, health departments, and urgent care centers.9 Patients at higher risk (injection drug users and their sex partners; people who exchange sex for money or drugs; sex partners of HIV-infected people; men who have sex with men; and heterosexuals who themselves or whose sex partners have had more than one sex partner since their most recent HIV test) should receive repeat screening annually.
HIV testing should also be offered to all pregnant women at entry into care and again in the third trimester. This strategy is cost-effective even in areas of low prevalence.9 Since 2006, other professional organizations have made HIV testing recommendations as well (Table 2).9–12
A cost-effectiveness analysis suggested that routine opt-out testing is economically justified if the prevalence of HIV is greater than 0.2%.13
HIV-POSITIVE WOMEN NEED ROUTINE GYNECOLOGIC CARE
It is important for women with HIV to receive routine gynecologic care. Women with HIV have gynecologic problems similar to those of all women; however, they may be more vulnerable to certain conditions such as human papillomavirus (HPV) infection, which may be related to HIV disease or associated immunosuppression. In addition, pregnancy and family planning pose special challenges in this group.14
Cervical cancer screening
Effective screening and timely treatment of precancerous cervical lesions are key in preventing cervical cancer in women with or without HIV.
Persistent infection with HPV is necessary for the development of precancerous lesions as well as invasive cervical cancer. Most new cases of HPV infection in the general population resolve spontaneously within 2 years. However, in HIV-infected women, HPV infection is more likely to persist and progress to precancerous lesions of the cervix. This association is strongest in women with more compromised immune function as reflected by low CD4 cell counts and high viral loads.14 Women with HIV have higher rates of infection with high-risk HPV strains and of cervical intraepithelial neoplasia compared with their HIV-negative counterparts.14 The incidence of cervical cancer is five to six times higher in HIV-infected women in the United States than in the general population.15
According to guidelines from the Infectious Diseases Society of America,16 the American College of Obstetricians and Gynecologists,10 the CDC,17 and the American Cancer Society,18 all HIV-infected women should undergo cervical Papanicolaou (Pap) screening upon initiation into care, and this test should be repeated at 6 months and then annually if the results are normal. Patients with abnormalities on the Pap test should undergo colposcopy and, possibly, also biopsy. These abnormalities include atypical squamous cells of unknown significance and higher-grade lesions.16
Nearly one-fourth of HIV-positive women do not receive annual Pap smears despite engagement in care.19 This is unacceptable, because half of the cases of cervical cancer diagnosed in the United States are in women who never received appropriate screening, and an additional 10% are in women who have not been screened in the previous 5 years.19
In HIV-infected women who have had a total hysterectomy, whether to continue Pap testing depends on their history before the surgery. Continued vaginal Pap smear screening is recommended after hysterectomy (including removal of the cervix) in HIV-infected women who have a history of cervical intraepithelial neoplasia grades 2 or 3 or invasive cancer.10,17,20
TREATING HIV IN WOMEN: SPECIAL CONSIDERATIONS
Because it is not yet possible to eradicate the HIV virus, the goals of antiretroviral therapy are to reduce HIV-associated morbidity and mortality, to restore and preserve immune function, to suppress viral load, and to prevent sexual and, in women, perinatal transmission of the virus.21
Antiretroviral therapy is recommended for all HIV-infected patients regardless of the CD4 count, although the strength of recommendation is weaker with higher CD4 counts (Table 3).21 The recommendations for starting antiretroviral therapy and the goals of treatment are the same for men and women. Table 4 summarizes the recommendations for adolescents and adults who are new to treatment.21 For women, additional factors that should be taken into account when considering a regimen include pregnancy potential and whether the drugs chosen for the regimen are considered safe in pregnancy.
Since the early years of the HIV epidemic, researchers have debated whether women attain the same benefits from antiretroviral therapy as men. US Food and Drug Administration investigators performed a meta-analysis of the efficacy outcomes in women in studies of antiretroviral drugs published between 2000 and 2008. They included randomized clinical trials reporting at least 48-week efficacy outcomes, with viral suppression defined as HIV RNA less than 50 copies/mL. The combined database included 40 trials of 16 drugs from 7 drug classes with a total of 20,328 HIV-positive participants. Overall, there were no clinically or statistically significant differences between the sexes in 48-week efficacy outcomes or in rates of trial discontinuation due to adverse events, loss to follow-up, or death.22
Antiretroviral therapy may, however, cause different adverse effects in women than in men. For example:
Nevirapine, a nonnucleoside reverse transcriptase inhibitor, has been associated with the development of a rash and potentially life-threatening hepatotoxicity, more commonly in women than in men and at lower CD4 counts in women. This resulted in recommendations21 to avoid starting a nevirapine-containing regimen in women with CD4 counts greater than 250 cells/mm3 and in men with CD4 counts greater than 400 cells/mm3.
Ritonavir has been observed to cause a higher incidence of nausea and vomiting in women and a higher incidence of diarrhea in men. These are thought to be due to differences between men and women in weight and pharmacokinetics.23
PRECONCEPTION COUNSELING FOR HIV-POSITIVE WOMEN
Preconception counseling is an essential component of both primary and preventive care and should be considered the standard of care for all women of reproductive age who have HIV.24 Health care providers who fully understand the impact of HIV infection and associated comorbidities upon a woman’s reproductive health, fertility desires, and family planning needs are better prepared to assist in their patients’ reproductive health decisions.
The first few weeks of pregnancy are the most critical period in fetal development. During this time, a woman should be healthy and avoid any activities or substances that could cause adverse maternal or fetal outcomes. However, most patients present for prenatal care after this critical time period—thus the need for preconception counseling. Both the Infectious Diseases Society of America and the HIV Medicine Association recommend that all HIV-infected women of childbearing age be asked about their pregnancy plans and desires at the start of care and routinely thereafter.16
The goals of preconception care in women with HIV are to prevent unintended pregnancy, optimize maternal health before pregnancy, optimize pregnancy outcomes for mother and fetus, prevent perinatal HIV transmission, and prevent HIV transmission to an HIV-negative partner when trying to conceive.24
Goal 1: Prevent unintended pregnancy
Nearly half of all pregnancies in the United States are unintended.25 Moreover, the Women’s Interagency HIV Study26 showed that women with HIV are underusing effective contraception. In the Medical Monitoring Project, 85% of the women who had been pregnant since being diagnosed with HIV said that at least one pregnancy was unplanned.27
The consequences of unintended and unplanned pregnancies are serious and add significant burden to women, men, and families. Women who do not wish to become pregnant should be advised to use an effective method of contraception.
Contraception
Contraception use varies worldwide. Factors affecting its use include the methods available, patient choice, current health conditions, religious beliefs, perception of method effectiveness, and side effects.24
The Women’s Interagency HIV Study evaluated trends in contraception use from 1998 to 2010. Condoms were the most common form of contraception, and their use changed little over time. Fewer than 15% of women with HIV used no contraception. The use of long-acting reversible contraception, including injectable progestins, implants, and intrauterine devices, which minimize the need for user adherence, increased among HIV-negative women but not among HIV-positive women.28
The World Health Organization states that all available methods are safe for women with HIV except for spermicides with or without a diaphragm, as there is evidence linking the use of spermicides to an increased risk of HIV transmission (Table 5).29
Some antiretroviral drugs may reduce the effectiveness of some contraceptives (Table 6); however, recommendations are based on pharmacokinetic studies, not on outcome studies. Condoms should be recommended not only to protect against pregnancy, but also to protect against sexually transmitted infections.
Goal 2: Optimize maternal health before pregnancy
Maternal health should be optimized before conceiving to reduce the risk of pregnancy-related morbidities and poor birth outcomes. This includes screening for other infections and ensuring that other comorbidities, such as hypertension, diabetes, substance abuse, and mental illness, are well managed with medications that are safe to use in pregnancy (Table 7).
Goal 3: Prevent perinatal HIV transmission
Educating the patient about perinatal transmission is a fundamental component of preconception counseling. Topics that need to be addressed are transmission risk and methods to reduce the risk, including not breastfeeding after delivery.
Goal 4: Prevent HIV transmission to an uninfected partner when trying to conceive
HIV-discordant couples who desire pregnancy should receive appropriate counseling about methods to minimize risk of transmission to the uninfected partner while trying to conceive. There are a number of effective methods and techniques, which are beyond the scope of this review. Key components of all methods are to screen for and treat sexually transmitted infections in both partners and to use effective antiretroviral therapy and attain maximal viral suppression in the HIV-positive partner.
Antiretroviral therapy for the HIV-infected partner significantly reduced the risk of HIV transmission by 96% in the HIV Prevention Trials Network 052 trial.30 Of note: this reduction was the result of both risk-reduction counseling and antiretroviral therapy. This was the first randomized clinical trial to demonstrate that antiretroviral therapy in those with some preserved immune function (CD4 counts 350–500 cells/mm3) in conjunction with risk-reduction counseling can reduce HIV transmission to an uninfected partner.
Vaginal insemination without intercourse is another option for female-positive couples. The man ejaculates into a condom without spermicide, and the contents are introduced with a non-needle syringe or turkey baster. This can be done at home and confers no risk to the uninfected male partner.31 Chances of pregnancy can be maximized by insemination during the most fertile days of the menstrual cycle.
Preexposure prophylaxis combined with timed intercourse. In a study in Switzerland, the infected male partner was given antiretroviral therapy to suppress his viral load to less than 50 copies/mL for at least 6 months, and luteinizing hormone was measured every day in the urine of the noninfected female partner. When the urinary luteinizing hormone level reached a peak, the woman received a dose of tenofovir in the morning, the couple had unprotected intercourse, and the woman took a second dose the next morning. In 53 cases, none of the female partners seroconverted for HIV.32
Health care providers need to document and update the relationship status, partner HIV status, and fertility desires of their HIV patients, both men and women, on a regular basis. Patient education should include awareness of referrals and options to help safely conceive when desired and achieve effective contraception when not.33
WHEN HIV-POSITIVE WOMEN BECOME PREGNANT
Screening for HIV during pregnancy
The CDC recommends prenatal screening for HIV in the first trimester or at entry into prenatal care. A repeat HIV test should be offered in the third trimester for women at risk of acquiring HIV, for women who have signs or symptoms of early HIV infection, in health care settings where prenatal testing yields at least 1 case of HIV infection per 1,000 women screened, and in areas of high HIV incidence. If women present to labor and delivery with unknown HIV status, rapid HIV testing should be done.9
If a woman acquires HIV during pregnancy, the infection may not be detected and may be transmitted to the infant at birth. From 2002 to 2006 in New York State, 3,396 HIV-exposed babies were born. Of these, 9 (22%) of 41 infants born to mothers who acquired HIV during pregnancy became infected, compared with 1.8% of those born to mothers who acquired HIV before pregnancy. Maternal acquisition of HIV during pregnancy was documented in only 1.3% of perinatal HIV exposures, but it was associated with 9 (13.8%) of the 65 perinatal transmission cases.34
Providers should be aware of the signs and symptoms of acute HIV infection and should have a low threshold for repeating HIV testing at any time during pregnancy. It has been estimated that 40% to 90% of patients with acute HIV infection experience fever, lymphadenopathy, pharyngitis, skin rash, myalgia, arthralgia, or other symptoms.35 Providers often do not recognize acute HIV infection, however, because the symptoms are similar to those of other common illnesses. Also, some individuals with the condition have no symptoms.
Antiretroviral therapy during pregnancy
In a landmark study, AIDS Clinical Trial Group 076 demonstrated that zidovudine monotherapy given during pregnancy, labor, and delivery and to the newborn reduced the risk of HIV transmission to the infant by 67%, from 25% to 8%.36 Other studies demonstrated that combination therapy further decreased the risk of HIV transmission to 1% to 2%.37
The US Department of Health and Human Services recommends that all HIV-positive women who are pregnant receive effective combination antiretroviral therapy regardless of CD4 count to minimize the risk of mother-to-child transmission.37
The goals of HIV treatment during pregnancy are to maintain the woman’s health, restore her immune system, suppress viral replication, and decrease the risk of perinatal transmission. The preferred antiretroviral therapy for pregnant women differs from that for nonpregnant women and is based on evolving experience and information about safety, efficacy, and tolerability in pregnancy (Table 8). A woman who presents for prenatal care on a suppressive regimen should continue that regimen as long as she can tolerate it because there is a risk of losing virologic control when switching regimens, and this may increase the risk of perinatal transmission.37
Physiologic changes that occur during pregnancy may alter drug disposition, which could potentially lead to decreased drug exposure. Some of the changes include an increase in total body water, decreased protein binding, induction of hepatic metabolic pathways, and increased clearance of drugs eliminated by the kidneys.38 These changes may be associated with incomplete virologic suppression, virologic failure, or development of drug resistance, so altered doses of some antiretroviral drugs or careful monitoring of viral load should be considered, particularly in the second and third trimester.
Delivery
Women who have a viral load greater than 1,000 copies/mL near the end of pregnancy should undergo a cesarean delivery at 38 weeks and, before surgery, should receive intravenous zidovudine to reduce the risk of perinatal transmission. For women with viral loads below the threshold of 1,000 copies/mL, there is no proven added benefit to cesarean delivery, and in this situation it should be performed only for standard obstetric indications. Antiretroviral regimens should be continued during labor.37
HIV IN OLDER ADULTS
By 2015, approximately 50% of people with HIV will be over age 50.39 Unfortunately, older people and their providers often underestimate their risk of acquiring HIV. Many older people are newly single and may engage in sexual activity with new partners. Also, older people may be reluctant to use condoms as the need for contraception is past.40,41
Baseline HIV RNA levels tend to be higher and CD4 cell counts lower in patients diagnosed with HIV at older ages. These observations support previous ones that older HIV-infected patients may have advanced HIV disease at the time of diagnosis, perhaps in part due to delayed testing.42 Other possible factors are limited income, comorbid illness, polypharmacy, and insufficient data on drug interactions in the elderly.41,42
A prompt diagnosis is important for older patients because HIV may accelerate aging, and aging may speed up HIV progression. Studies have shown that aging is associated with more rapid progression to AIDS, particularly among people who are older than 40 at seroconversion.43 Other studies have reported that older patients have better virologic responses to antiretroviral therapy but have a blunted immune response, more AIDS-defining events, and a higher mortality rate than younger patients.42
- Centers for Disease Control and Prevention (CDC). Immunodeficiency among female sexual partners of males with acquired immune deficiency syndrome (AIDS) - New York. MMWR Morb Mortal Wkly Rep 1983; 31:697–698.
- Centers for Disease Control and Prevention (CDC). Estimated HIV incidence in the United States, 2007–2010. HIV Surveillance Supplemental Report 2012; 17( No. 4). www.cdc.gov/hiv/topics/surveillance/resources/reports/#supplemental. Accessed October 3, 2014.
- Centers for Disease Control and Prevention. HIV in the United States: at a glance. www.cdc.gov/hiv/statistics/basics/ataglance.html. Accessed October 3, 2014.
- El-Sadr WM, Mayer KH, Hodder SL. AIDS in America—forgotten but not gone. N Engl J Med 2010; 362:967–970.
- Eshleman SH, Hughes JP, Laeyendecker O, et al. Use of a multifaceted approach to analyze HIV incidence in a cohort study of women in the United States: HIV Prevention Trials Network 064 Study. J Infect Dis 2013; 207:223–231.
- Djokic D, Englund J, Daum R, et al. HIV knowledge and attitudes toward HIV testing of South Side Chicago Housing Authority residents. AIDS Patient Care STDS 2009; 23:23–28.
- Samji H, Cescon A, Hogg RS, et al; North American AIDS Cohort Collaboration on Research and Design (NA-ACCORD) of IeDEA. Closing the gap: increases in life expectancy among treated HIV-positive individuals in the United States and Canada. PLoS One 2013; 8:e81355.
- Centers for Disease Control and Prevention (CDC). HIV/AIDS. HIV mortality (through 2010). www.cdc.gov/hiv/library/slideSets/index.html. Accessed October 3, 2014.
- Branson BM, Handsfield HH, Lampe MA, et al; Centers for Disease Control and Prevention (CDC). Revised recommendations for HIV testing of adults, adolescents, and pregnant women in health-care settings. MMWR Recomm Rep 2006; 55:1–17.
- The American College of Obstetricians and Gynecologists (ACOG). Routine Human Immunodeficiency Virus Screening Committee Opinion Number 596, May 2014. (Replaces Committee Opinion Number 411, August 2008.) www.acog.org/Resources_And_Publications/Committee_Opinions/Committee_on_Gynecologic_Practice/Routine_Human_Immunodeficiency_Virus_Screening. Accessed October 3, 2014.
- US Preventive Services Task Force. Screening for HIV. http://www.uspreventiveservicestaskforce.org/Page/Topic/recommendation-summary/human-immunodeficiency-virus-hiv-infection-screening. Accessed October 3, 2014.
- Institute of Medicine. HIV screening and access to care health care system capacity for increased HIV testing and provision of care. www.iom.edu/Reports/2011/HIV-Screening-and-Access-to-Care-Health-Care-System-Capacity-for-Increased-HIV-Testing-and-Provision-of-Care.aspx. Accessed October 3, 2014.
- Walensky RP, Freedberg KA, Weinstein MC, Paltiel AD. Cost-effectiveness of HIV testing and treatment in the United States. Clin Infect Dis 2007; 45(suppl 4):S248–S254.
- ACOG Committee on Practice Bulletins—Gynecology. ACOG Practice Bulletin No. 117: Gynecologic care for women with human immunodeficiency virus. Obstet Gynecol 2010; 116:1492–1509.
- Centers for Disease Control and Prevention (CDC). Invasive cancer incidence—United States, 2009. MMWR Morb Mortal Wkly Rep 2013; 62:113–118.
- Aberg JA, Gallant JE, Ghanem KG, Emmanuel P, Zingman BS, Horberg MA. Primary care guidelines for the management of persons infected with HIV: 2013 update by the HIV Medicine Association of the Infectious Diseases Society of America. Clin Infect Dis 2014; 58:e1–e34.
- Panel on Opportunistic Infections in HIV-Infected Adults and Adolescents. Guidelines for the prevention and treatment of opportunistic infections in HIV-infected adults and adolescents: recommendations from the Centers for Disease Control and Prevention, the National Institutes of Health, and the HIV Medicine Association of the Infectious Diseases Society of America. http://aidsinfo.nih.gov/contentfiles/lvguidelines/adult_oi.pdf. Accessed October 3, 2014.
- Saslow D, Solomon D, Lawson HW, et al; ACS-ASCCP-ASCP Cervical Cancer Guideline Committee. American Cancer Society, American Society for Colposcopy and Cervical Pathology, and American Society for Clinical Pathology screening guidelines for the prevention and early detection of cervical cancer. CA Cancer J Clin 2012; 62:147–172.
- Oster AM, Sullivan PS, Blair JM. Prevalence of cervical cancer screening of HIV-infected women in the United States. J Acquir Immune Defic Syndr 2009; 51:430–436.
- Paramsothy P, Duerr A, Heilig CM, et al; HIV Epidemiology Research (HER) Study Group. Abnormal vaginal cytology in HIV-infected and at-risk women after hysterectomy. J Acquir Immune Defic Syndr 2004; 35:484–491.
- Panel on Antiretroviral Guidelines for Adults and Adolescents. Guidelines for the use of antiretroviral agents in HIV-1-infected adults and adolescents. Department of Health and Human Services. http://aidsinfo.nih.gov/ContentFiles/AdultandAdolescentGL.pdf. Accessed October 3, 2014.
- Soon GG, Min M, Struble KA, et al. Meta-analysis of gender differences in efficacy outcomes for HIV-positive subjects in randomized controlled clinical trials of antiretroviral therapy (2000–2008). AIDS Patient Care STDS 2012; 26:444–453.
- Clark RA, Squires KE. Gender-specific considerations in the antiretroviral management of HIV-infected women. Expert Rev Anti Infect Ther 2005; 3:213–227.
- Johnson K, Posner SF, Biermann J, et al; CDC/ATSDR Preconception Care Work Group; Select Panel on Preconception Care. Recommendations to improve preconception health and health care—United States. A report of the CDC/ATSDR Preconception Care Work Group and the Select Panel on Preconception Care. MMWR Recomm Rep 2006; 55:1–23.
- Finer LB, Zolna MR. Unintended pregnancy in the United States: incidence and disparities, 2006. Contraception 2011; 84:478–485.
- Massad LS, Evans CT, Wilson TE, et al. Contraceptive use among US women with HIV. J Womens Health (Larchmt) 2007; 16:657–666.
- Sutton MY, Patel R, Frazier EL. Unplanned pregnancies among HIV-infected women in care-United States. J Acquir Immune Defic Syndr 2014; 65:350–358.
- Sun M, Peipert JF, Zhao Q, et al. Trends in contraceptive use among women with human immunodeficiency virus. Obstet Gynecol 2012; 120:783–790.
- World Health Organization (WHO). Medical eligibility criteria for contraceptive use. 4th ed. http://whqlibdoc.who.int/publications/2010/9789241563888_eng.pdf. Accessed October 3, 2014.
- Cohen MS, Chen YQ, McCauley M, et al; HPTN 052 Study Team. Prevention of HIV-1 infection with early antiretroviral therapy. N Engl J Med 2011; 365:493–505.
- Mmeje O, Cohen CR, Cohan D. Evaluating safer conception options for HIV-serodiscordant couples (HIV-infected female/HIV-uninfected male): a closer look at vaginal insemination. Infect Dis Obstet Gynecol 2012; 2012:587–651.
- Vernazza PL, Graf I, Sonnenberg-Schwan U, Geit M, Meurer A. Preexposure prophylaxis and timed intercourse for HIV-discordant couples willing to conceive a child. AIDS 2011; 25:2005–2008.
- Lampe MA, Smith DK, Anderson GJ, Edwards AE, Nesheim SR. Achieving safe conception in HIV-discordant couples: the potential role of oral preexposure prophylaxis (PrEP) in the United States. Am J Obstet Gynecol 2011; 204:488.e1–e8.
- Birkhead GS, Pulver WP, Warren BL, Hackel S, Rodríguez D, Smith L. Acquiring human immunodeficiency virus during pregnancy and mother-to-child transmission in New York: 2002–2006. Obstet Gynecol 2010; 115:1247–1255.
- Yerly S, Hirschel B. Diagnosing acute HIV infection. Expert Rev Anti Infect Ther 2012; 10:31–41.
- Connor EM, Sperling RS, Gelber R, et al. Reduction of maternal-infant transmission of human immunodeficiency virus type 1 with zidovudine treatment. Pediatric AIDS Clinical Trials Group Protocol 076 Study Group. N Engl J Med 1994; 331:1173–1180.
- Panel on Treatment of HIV-Infected Pregnant Women and Prevention of Perinatal Transmission. Recommendations for use of antiretroviral drugs in pregnant HIV-1-infected women for maternal health and interventions to reduce perinatal HIV transmission in the United States. http://aidsinfo.nih.gov/contentfiles/lvguidelines/PerinatalGL.pdf. Accessed October 3, 2014.
- Mirochnick M, Capparelli E. Pharmacokinetics of antiretrovirals in pregnant women. Clin Pharmacokinet 2004; 43:1071–1087.
- Smith GSenate Committee on Aging. HIV over fifty: exploring the new threat. Washington, DC; 2005. http://www.aging.senate.gov/imo/media/doc/5122005.pdf. Accessed October 3, 2014.
- Illa L, Brickman A, Saint-Jean G, et al. Sexual risk behaviors in late middle age and older HIV seropositive adults. AIDS Behav 2008; 12:935–942.
- Luther VP, Wilkin AM. HIV infection in older adults. Clin Geriatr Med 2007; 23:567–583.
- Collaboration of Observational HIV Epidemiological Research Europe (COHERE) Study Group; Sabin CA, Smith CJ, d’Arminio Monforte A, et al. Response to combination antiretroviral therapy: variation by age. AIDS 2008; 22:1463–1473.
- Pezzotti P, Phillips AN, Dorrucci M, et al. Category of exposure to HIV and age in the progression to AIDS: longitudinal study of 1,199 people with known dates of seroconversion. HIV Italian Seroconversion Study Group. BMJ 1996; 313:583–586.
- Centers for Disease Control and Prevention (CDC). Immunodeficiency among female sexual partners of males with acquired immune deficiency syndrome (AIDS) - New York. MMWR Morb Mortal Wkly Rep 1983; 31:697–698.
- Centers for Disease Control and Prevention (CDC). Estimated HIV incidence in the United States, 2007–2010. HIV Surveillance Supplemental Report 2012; 17( No. 4). www.cdc.gov/hiv/topics/surveillance/resources/reports/#supplemental. Accessed October 3, 2014.
- Centers for Disease Control and Prevention. HIV in the United States: at a glance. www.cdc.gov/hiv/statistics/basics/ataglance.html. Accessed October 3, 2014.
- El-Sadr WM, Mayer KH, Hodder SL. AIDS in America—forgotten but not gone. N Engl J Med 2010; 362:967–970.
- Eshleman SH, Hughes JP, Laeyendecker O, et al. Use of a multifaceted approach to analyze HIV incidence in a cohort study of women in the United States: HIV Prevention Trials Network 064 Study. J Infect Dis 2013; 207:223–231.
- Djokic D, Englund J, Daum R, et al. HIV knowledge and attitudes toward HIV testing of South Side Chicago Housing Authority residents. AIDS Patient Care STDS 2009; 23:23–28.
- Samji H, Cescon A, Hogg RS, et al; North American AIDS Cohort Collaboration on Research and Design (NA-ACCORD) of IeDEA. Closing the gap: increases in life expectancy among treated HIV-positive individuals in the United States and Canada. PLoS One 2013; 8:e81355.
- Centers for Disease Control and Prevention (CDC). HIV/AIDS. HIV mortality (through 2010). www.cdc.gov/hiv/library/slideSets/index.html. Accessed October 3, 2014.
- Branson BM, Handsfield HH, Lampe MA, et al; Centers for Disease Control and Prevention (CDC). Revised recommendations for HIV testing of adults, adolescents, and pregnant women in health-care settings. MMWR Recomm Rep 2006; 55:1–17.
- The American College of Obstetricians and Gynecologists (ACOG). Routine Human Immunodeficiency Virus Screening Committee Opinion Number 596, May 2014. (Replaces Committee Opinion Number 411, August 2008.) www.acog.org/Resources_And_Publications/Committee_Opinions/Committee_on_Gynecologic_Practice/Routine_Human_Immunodeficiency_Virus_Screening. Accessed October 3, 2014.
- US Preventive Services Task Force. Screening for HIV. http://www.uspreventiveservicestaskforce.org/Page/Topic/recommendation-summary/human-immunodeficiency-virus-hiv-infection-screening. Accessed October 3, 2014.
- Institute of Medicine. HIV screening and access to care health care system capacity for increased HIV testing and provision of care. www.iom.edu/Reports/2011/HIV-Screening-and-Access-to-Care-Health-Care-System-Capacity-for-Increased-HIV-Testing-and-Provision-of-Care.aspx. Accessed October 3, 2014.
- Walensky RP, Freedberg KA, Weinstein MC, Paltiel AD. Cost-effectiveness of HIV testing and treatment in the United States. Clin Infect Dis 2007; 45(suppl 4):S248–S254.
- ACOG Committee on Practice Bulletins—Gynecology. ACOG Practice Bulletin No. 117: Gynecologic care for women with human immunodeficiency virus. Obstet Gynecol 2010; 116:1492–1509.
- Centers for Disease Control and Prevention (CDC). Invasive cancer incidence—United States, 2009. MMWR Morb Mortal Wkly Rep 2013; 62:113–118.
- Aberg JA, Gallant JE, Ghanem KG, Emmanuel P, Zingman BS, Horberg MA. Primary care guidelines for the management of persons infected with HIV: 2013 update by the HIV Medicine Association of the Infectious Diseases Society of America. Clin Infect Dis 2014; 58:e1–e34.
- Panel on Opportunistic Infections in HIV-Infected Adults and Adolescents. Guidelines for the prevention and treatment of opportunistic infections in HIV-infected adults and adolescents: recommendations from the Centers for Disease Control and Prevention, the National Institutes of Health, and the HIV Medicine Association of the Infectious Diseases Society of America. http://aidsinfo.nih.gov/contentfiles/lvguidelines/adult_oi.pdf. Accessed October 3, 2014.
- Saslow D, Solomon D, Lawson HW, et al; ACS-ASCCP-ASCP Cervical Cancer Guideline Committee. American Cancer Society, American Society for Colposcopy and Cervical Pathology, and American Society for Clinical Pathology screening guidelines for the prevention and early detection of cervical cancer. CA Cancer J Clin 2012; 62:147–172.
- Oster AM, Sullivan PS, Blair JM. Prevalence of cervical cancer screening of HIV-infected women in the United States. J Acquir Immune Defic Syndr 2009; 51:430–436.
- Paramsothy P, Duerr A, Heilig CM, et al; HIV Epidemiology Research (HER) Study Group. Abnormal vaginal cytology in HIV-infected and at-risk women after hysterectomy. J Acquir Immune Defic Syndr 2004; 35:484–491.
- Panel on Antiretroviral Guidelines for Adults and Adolescents. Guidelines for the use of antiretroviral agents in HIV-1-infected adults and adolescents. Department of Health and Human Services. http://aidsinfo.nih.gov/ContentFiles/AdultandAdolescentGL.pdf. Accessed October 3, 2014.
- Soon GG, Min M, Struble KA, et al. Meta-analysis of gender differences in efficacy outcomes for HIV-positive subjects in randomized controlled clinical trials of antiretroviral therapy (2000–2008). AIDS Patient Care STDS 2012; 26:444–453.
- Clark RA, Squires KE. Gender-specific considerations in the antiretroviral management of HIV-infected women. Expert Rev Anti Infect Ther 2005; 3:213–227.
- Johnson K, Posner SF, Biermann J, et al; CDC/ATSDR Preconception Care Work Group; Select Panel on Preconception Care. Recommendations to improve preconception health and health care—United States. A report of the CDC/ATSDR Preconception Care Work Group and the Select Panel on Preconception Care. MMWR Recomm Rep 2006; 55:1–23.
- Finer LB, Zolna MR. Unintended pregnancy in the United States: incidence and disparities, 2006. Contraception 2011; 84:478–485.
- Massad LS, Evans CT, Wilson TE, et al. Contraceptive use among US women with HIV. J Womens Health (Larchmt) 2007; 16:657–666.
- Sutton MY, Patel R, Frazier EL. Unplanned pregnancies among HIV-infected women in care-United States. J Acquir Immune Defic Syndr 2014; 65:350–358.
- Sun M, Peipert JF, Zhao Q, et al. Trends in contraceptive use among women with human immunodeficiency virus. Obstet Gynecol 2012; 120:783–790.
- World Health Organization (WHO). Medical eligibility criteria for contraceptive use. 4th ed. http://whqlibdoc.who.int/publications/2010/9789241563888_eng.pdf. Accessed October 3, 2014.
- Cohen MS, Chen YQ, McCauley M, et al; HPTN 052 Study Team. Prevention of HIV-1 infection with early antiretroviral therapy. N Engl J Med 2011; 365:493–505.
- Mmeje O, Cohen CR, Cohan D. Evaluating safer conception options for HIV-serodiscordant couples (HIV-infected female/HIV-uninfected male): a closer look at vaginal insemination. Infect Dis Obstet Gynecol 2012; 2012:587–651.
- Vernazza PL, Graf I, Sonnenberg-Schwan U, Geit M, Meurer A. Preexposure prophylaxis and timed intercourse for HIV-discordant couples willing to conceive a child. AIDS 2011; 25:2005–2008.
- Lampe MA, Smith DK, Anderson GJ, Edwards AE, Nesheim SR. Achieving safe conception in HIV-discordant couples: the potential role of oral preexposure prophylaxis (PrEP) in the United States. Am J Obstet Gynecol 2011; 204:488.e1–e8.
- Birkhead GS, Pulver WP, Warren BL, Hackel S, Rodríguez D, Smith L. Acquiring human immunodeficiency virus during pregnancy and mother-to-child transmission in New York: 2002–2006. Obstet Gynecol 2010; 115:1247–1255.
- Yerly S, Hirschel B. Diagnosing acute HIV infection. Expert Rev Anti Infect Ther 2012; 10:31–41.
- Connor EM, Sperling RS, Gelber R, et al. Reduction of maternal-infant transmission of human immunodeficiency virus type 1 with zidovudine treatment. Pediatric AIDS Clinical Trials Group Protocol 076 Study Group. N Engl J Med 1994; 331:1173–1180.
- Panel on Treatment of HIV-Infected Pregnant Women and Prevention of Perinatal Transmission. Recommendations for use of antiretroviral drugs in pregnant HIV-1-infected women for maternal health and interventions to reduce perinatal HIV transmission in the United States. http://aidsinfo.nih.gov/contentfiles/lvguidelines/PerinatalGL.pdf. Accessed October 3, 2014.
- Mirochnick M, Capparelli E. Pharmacokinetics of antiretrovirals in pregnant women. Clin Pharmacokinet 2004; 43:1071–1087.
- Smith GSenate Committee on Aging. HIV over fifty: exploring the new threat. Washington, DC; 2005. http://www.aging.senate.gov/imo/media/doc/5122005.pdf. Accessed October 3, 2014.
- Illa L, Brickman A, Saint-Jean G, et al. Sexual risk behaviors in late middle age and older HIV seropositive adults. AIDS Behav 2008; 12:935–942.
- Luther VP, Wilkin AM. HIV infection in older adults. Clin Geriatr Med 2007; 23:567–583.
- Collaboration of Observational HIV Epidemiological Research Europe (COHERE) Study Group; Sabin CA, Smith CJ, d’Arminio Monforte A, et al. Response to combination antiretroviral therapy: variation by age. AIDS 2008; 22:1463–1473.
- Pezzotti P, Phillips AN, Dorrucci M, et al. Category of exposure to HIV and age in the progression to AIDS: longitudinal study of 1,199 people with known dates of seroconversion. HIV Italian Seroconversion Study Group. BMJ 1996; 313:583–586.
KEY POINTS
- The number of women living with HIV has increased over the past 30 years, and African American women bear a disproportionate burden of disease.
- Women of all ages are at risk of acquiring HIV; therefore, HIV testing should be part of routine care.
- Preconception counseling is an essential component of both primary and preventive care and should be the standard of care for all women of reproductive age with HIV.
- Women with HIV have the same gynecologic problems as all women but may be more vulnerable to certain conditions, such as human papillomavirus infection.
Women and HIV: An expanded perspective
In this issue of the Cleveland Clinic Journal of Medicine, Drs. Short and Anderson give an overview of the epidemic of human immunodeficiency virus (HIV) infection in US women and the various aspects of health care of this group, including pregnancy.1 They introduce a much broader topic and bring to light a number of additional concerns.
HIV PREYS ON THE VULNERABLE
The authors review epidemiologic trends and the evolving demographics of HIV, which deserve specific discussion.
In the early years of the epidemic, ie, the early 1980s, HIV infection in women was overshadowed by the epidemic in men, particularly men who have sex with men. The epidemic in men who have sex with men remains the larger component of the HIV picture in the United States. But worldwide, HIV is an evenly balanced problem, with nearly half of all infections occurring in women.2 Women have received much more attention recently.
In the United States, about 300,000 women are living with HIV, and 10% of them are unaware of it. Between 1985 and 2013, the number of HIV cases in US women tripled.
The epidemic continues to disproportionately affect women of color. Two-thirds of all women with HIV are African American,2 and estimates suggest that 1 of every 32 African American women will acquire HIV during her lifetime. On a positive note, there was a 20% reduction in new infections among African American women between 2008 and 2010.3
The epidemic preys on the vulnerable and is fueled by poverty, lack of education (general and health literacy), substance abuse, and restricted access to health care. Major metropolitan areas such as New York, Washington, DC, Miami, and Los Angeles are “hot spots,” where high concentrations of infected people reside.4
Many women underestimate or do not perceive their susceptibility. They unknowingly acquire HIV infection from their male partners, many of whom are unaware of their infection. Some of their partners may lead a dual life of bisexuality. In some areas, an estimated 20% of men who have sex with men also engage in sex with women.5 If these women contract the disease, they may be diagnosed at a late stage and when they are symptomatic, or coincidentally during pregnancy and childbirth.
Negotiating safe sex practices can be difficult for a woman. She may perceive or lack empowerment to do so, fearing rejection, isolation, or violence. Sexual violence may have been initiated in childhood, through intimate partners, rape, sex trafficking, or prostitution. Patterns vary throughout the world, but sexual violence is more common than perceived.6 Because of shame, embarrassment, and isolation, many victims do not seek medical care and so may carry undiagnosed infections. Even when they access care, they are less likely to remain in the HIV care system.7 Greater efforts are needed to reach these women, make them feel supported in care, and keep them in the system.
TESTING IS CRUCIAL
Diagnosis remains a weak link in the chain of care for both men and women. Success has been noted in the form of a marked reduction in cases of mother-to-child transmission, thanks to near-universal opt-out screening during pregnancy or at delivery.
If appropriate routine testing were done for all people, as advocated by the US Centers for Disease Control and Prevention guidelines,8 more cases could be diagnosed, behaviors changed, and treatment offered. Control of HIV through treatment can lead to a 96% reduction in transmission between serodiscordant partners, as demonstrated in HPTN 052, an ongoing phase 3 trial.9 Early diagnosis and treatment offer the potential for improved immune regeneration and healthier lives.
PRE-EXPOSURE PROPHYLAXIS
Pre-exposure prophylaxis (PrEP) is one approach to empowering women and preventing HIV infection. Studies have demonstrated the efficacy of this approach, although some studies have not.10,11
An important finding in the failed studies appeared to be a lack of adherence to the regimen.11 Unless taken faithfully, PrEP will not succeed. Additionally, there may be inherent differences in outcomes for unknown reasons. Lack of access to the necessary two-drug combination regimen is another barrier.
PrEP is expensive, requires regular monitoring, and requires patients to remain engaged in medical care. Currently, not all medical programs offer PrEP, and not all insurance policies cover it. Further insight into long-term side effects and complications is needed.
Although PrEP is an attractive concept and a reality for some, it is an incomplete solution to prevention at this time.
MEN AND WOMEN ARE DIFFERENT
Men and women are different physiologically and psychologically. Women typically have a lower body mass, lower bone mass, and higher content of body fat. As a result, women may differ from men in their ability to tolerate medications, and long-term side effects may be more pronounced.
Women are also more likely to place family responsibilities above self-preservation and personal health concerns. As a result, providing for and taking care of their children takes precedence over care of their own health.
Providing care to women presents many challenges and opportunities to improve their health. Health care access, transportation, assistance with child care during medical visits, the availability of counseling to deal with shame, guilt, and depression, and maintaining women within the care system are but a few examples.
AGING WITH HIV: STUDY NEEDED
Antiretroviral therapy has enabled patients to survive and often to reach a normal life expectancy if the infection is diagnosed and treated early. As a result, HIV-associated causes of death have been replaced by non-HIV comorbidities typical of aging, such as cardiovascular disease, organ failure (heart, lung, kidney, liver), non-HIV cancers, and bone disease.
Women face unique aspects of aging with menopause, including an accelerated rate of bone loss resulting in osteoporosis. HIV itself and some antiretroviral drugs may increase the loss of bone mineral density. Alcohol abuse, sedentary lifestyle, smoking, hepatitis C co-infection, and poor nutrition also contribute to this problem. Bone disease and many other aspects of aging and HIV in women require more research and intervention.
Other areas that need to be studied are the unique mucosal immune system of the female genital tract, the interplay of sex hormones and the immune system, the role of genital tract inflammation in increasing the risk of HIV acquisition, sexual violence and HIV acquisition, and the safety and efficacy of PrEP for women. This will require prioritization and ongoing funding, which is becoming scarcer. If there is to be hope of containing this disease, our efforts to understand it must not diminish.
- Short WR, Anderson JR. Caring for women with HIV: unique needs and challenges. Cleve Clin J Med 2014; 81:691–701.
- UNAIDS. Women out loud: how women living with HIV will help the world end AIDS. www.unaids.org/en/media/unaids/contentassets/documents/unaidspublication/2012/20121211_Women_Out_Loud_en.pdf. Accessed October 2, 2014.
- Centers for Disease Control and Prevention (CDC). HIV among women. www.cdc.gov/hiv/risk/gender/women/index.html. Accessed October 2, 2014.
- Hodder SL, Justman J, Hughes JP, et al; HIV Prevention Trials Network 064; Women’s HIV SeroIncidence Study Team. HIV acquisition among women from selected areas of the United States: a cohort study. Ann Intern Med 2013; 158:10–18.
- UNAIDS. Fact Sheet: women, girls, gender equality and HIV. www.unaids.org/en/media/unaids/contentassets/documents/factsheet/2012/20120217_FS_WomenGirls_en.pdf. Accessed October 2, 2014.
- Centers for Disease Control and Prevention (CDC). National intimate partner and sexual violence survey: 2010 summary report. www.cdc.gov/violenceprevention/pdf/nisvs_executive_summary-a.pdf. Accessed October 2, 2014.
- Siemieniuk RA, Krentz HB, Miller P, Woodman K, Ko K, Gill MJ. The clinical implications of high rates of intimate partner violence against HIV-positive women. J Acquir Immune Defic Syndr 2013; 64:32–38.
- Branson BM, Handsfield HH, Lampe MA, et al; Centers for Disease Control and Prevention (CDC). Revised recommendations for HIV testing of adults, adolescents, and pregnant women in health-care settings. MMWR Recomm Rep 2006; 55:1–17.
- Cohen MS, Chen YQ, McCauley M, et al; HPTN 052 Study Team. Prevention of HIV-1 infection with early antiretroviral therapy. N Engl J Med 2011; 365:493–505.
- Grant RM, Lama JR, Anderson PL, et al; iPrEx Study Team. Preexposure chemoprophylaxis for HIV prevention in men who have sex with men. N Engl J Med 2010; 363:2587–2599.
- Haberer JE, Baeten JM, Campbell J, et al. Adherence to antiretroviral prophylaxis for HIV prevention: a substudy cohort within a clinical trial of serodiscordant couples in East Africa. PLoS Med 2013; 10 9:e1001511.
In this issue of the Cleveland Clinic Journal of Medicine, Drs. Short and Anderson give an overview of the epidemic of human immunodeficiency virus (HIV) infection in US women and the various aspects of health care of this group, including pregnancy.1 They introduce a much broader topic and bring to light a number of additional concerns.
HIV PREYS ON THE VULNERABLE
The authors review epidemiologic trends and the evolving demographics of HIV, which deserve specific discussion.
In the early years of the epidemic, ie, the early 1980s, HIV infection in women was overshadowed by the epidemic in men, particularly men who have sex with men. The epidemic in men who have sex with men remains the larger component of the HIV picture in the United States. But worldwide, HIV is an evenly balanced problem, with nearly half of all infections occurring in women.2 Women have received much more attention recently.
In the United States, about 300,000 women are living with HIV, and 10% of them are unaware of it. Between 1985 and 2013, the number of HIV cases in US women tripled.
The epidemic continues to disproportionately affect women of color. Two-thirds of all women with HIV are African American,2 and estimates suggest that 1 of every 32 African American women will acquire HIV during her lifetime. On a positive note, there was a 20% reduction in new infections among African American women between 2008 and 2010.3
The epidemic preys on the vulnerable and is fueled by poverty, lack of education (general and health literacy), substance abuse, and restricted access to health care. Major metropolitan areas such as New York, Washington, DC, Miami, and Los Angeles are “hot spots,” where high concentrations of infected people reside.4
Many women underestimate or do not perceive their susceptibility. They unknowingly acquire HIV infection from their male partners, many of whom are unaware of their infection. Some of their partners may lead a dual life of bisexuality. In some areas, an estimated 20% of men who have sex with men also engage in sex with women.5 If these women contract the disease, they may be diagnosed at a late stage and when they are symptomatic, or coincidentally during pregnancy and childbirth.
Negotiating safe sex practices can be difficult for a woman. She may perceive or lack empowerment to do so, fearing rejection, isolation, or violence. Sexual violence may have been initiated in childhood, through intimate partners, rape, sex trafficking, or prostitution. Patterns vary throughout the world, but sexual violence is more common than perceived.6 Because of shame, embarrassment, and isolation, many victims do not seek medical care and so may carry undiagnosed infections. Even when they access care, they are less likely to remain in the HIV care system.7 Greater efforts are needed to reach these women, make them feel supported in care, and keep them in the system.
TESTING IS CRUCIAL
Diagnosis remains a weak link in the chain of care for both men and women. Success has been noted in the form of a marked reduction in cases of mother-to-child transmission, thanks to near-universal opt-out screening during pregnancy or at delivery.
If appropriate routine testing were done for all people, as advocated by the US Centers for Disease Control and Prevention guidelines,8 more cases could be diagnosed, behaviors changed, and treatment offered. Control of HIV through treatment can lead to a 96% reduction in transmission between serodiscordant partners, as demonstrated in HPTN 052, an ongoing phase 3 trial.9 Early diagnosis and treatment offer the potential for improved immune regeneration and healthier lives.
PRE-EXPOSURE PROPHYLAXIS
Pre-exposure prophylaxis (PrEP) is one approach to empowering women and preventing HIV infection. Studies have demonstrated the efficacy of this approach, although some studies have not.10,11
An important finding in the failed studies appeared to be a lack of adherence to the regimen.11 Unless taken faithfully, PrEP will not succeed. Additionally, there may be inherent differences in outcomes for unknown reasons. Lack of access to the necessary two-drug combination regimen is another barrier.
PrEP is expensive, requires regular monitoring, and requires patients to remain engaged in medical care. Currently, not all medical programs offer PrEP, and not all insurance policies cover it. Further insight into long-term side effects and complications is needed.
Although PrEP is an attractive concept and a reality for some, it is an incomplete solution to prevention at this time.
MEN AND WOMEN ARE DIFFERENT
Men and women are different physiologically and psychologically. Women typically have a lower body mass, lower bone mass, and higher content of body fat. As a result, women may differ from men in their ability to tolerate medications, and long-term side effects may be more pronounced.
Women are also more likely to place family responsibilities above self-preservation and personal health concerns. As a result, providing for and taking care of their children takes precedence over care of their own health.
Providing care to women presents many challenges and opportunities to improve their health. Health care access, transportation, assistance with child care during medical visits, the availability of counseling to deal with shame, guilt, and depression, and maintaining women within the care system are but a few examples.
AGING WITH HIV: STUDY NEEDED
Antiretroviral therapy has enabled patients to survive and often to reach a normal life expectancy if the infection is diagnosed and treated early. As a result, HIV-associated causes of death have been replaced by non-HIV comorbidities typical of aging, such as cardiovascular disease, organ failure (heart, lung, kidney, liver), non-HIV cancers, and bone disease.
Women face unique aspects of aging with menopause, including an accelerated rate of bone loss resulting in osteoporosis. HIV itself and some antiretroviral drugs may increase the loss of bone mineral density. Alcohol abuse, sedentary lifestyle, smoking, hepatitis C co-infection, and poor nutrition also contribute to this problem. Bone disease and many other aspects of aging and HIV in women require more research and intervention.
Other areas that need to be studied are the unique mucosal immune system of the female genital tract, the interplay of sex hormones and the immune system, the role of genital tract inflammation in increasing the risk of HIV acquisition, sexual violence and HIV acquisition, and the safety and efficacy of PrEP for women. This will require prioritization and ongoing funding, which is becoming scarcer. If there is to be hope of containing this disease, our efforts to understand it must not diminish.
In this issue of the Cleveland Clinic Journal of Medicine, Drs. Short and Anderson give an overview of the epidemic of human immunodeficiency virus (HIV) infection in US women and the various aspects of health care of this group, including pregnancy.1 They introduce a much broader topic and bring to light a number of additional concerns.
HIV PREYS ON THE VULNERABLE
The authors review epidemiologic trends and the evolving demographics of HIV, which deserve specific discussion.
In the early years of the epidemic, ie, the early 1980s, HIV infection in women was overshadowed by the epidemic in men, particularly men who have sex with men. The epidemic in men who have sex with men remains the larger component of the HIV picture in the United States. But worldwide, HIV is an evenly balanced problem, with nearly half of all infections occurring in women.2 Women have received much more attention recently.
In the United States, about 300,000 women are living with HIV, and 10% of them are unaware of it. Between 1985 and 2013, the number of HIV cases in US women tripled.
The epidemic continues to disproportionately affect women of color. Two-thirds of all women with HIV are African American,2 and estimates suggest that 1 of every 32 African American women will acquire HIV during her lifetime. On a positive note, there was a 20% reduction in new infections among African American women between 2008 and 2010.3
The epidemic preys on the vulnerable and is fueled by poverty, lack of education (general and health literacy), substance abuse, and restricted access to health care. Major metropolitan areas such as New York, Washington, DC, Miami, and Los Angeles are “hot spots,” where high concentrations of infected people reside.4
Many women underestimate or do not perceive their susceptibility. They unknowingly acquire HIV infection from their male partners, many of whom are unaware of their infection. Some of their partners may lead a dual life of bisexuality. In some areas, an estimated 20% of men who have sex with men also engage in sex with women.5 If these women contract the disease, they may be diagnosed at a late stage and when they are symptomatic, or coincidentally during pregnancy and childbirth.
Negotiating safe sex practices can be difficult for a woman. She may perceive or lack empowerment to do so, fearing rejection, isolation, or violence. Sexual violence may have been initiated in childhood, through intimate partners, rape, sex trafficking, or prostitution. Patterns vary throughout the world, but sexual violence is more common than perceived.6 Because of shame, embarrassment, and isolation, many victims do not seek medical care and so may carry undiagnosed infections. Even when they access care, they are less likely to remain in the HIV care system.7 Greater efforts are needed to reach these women, make them feel supported in care, and keep them in the system.
TESTING IS CRUCIAL
Diagnosis remains a weak link in the chain of care for both men and women. Success has been noted in the form of a marked reduction in cases of mother-to-child transmission, thanks to near-universal opt-out screening during pregnancy or at delivery.
If appropriate routine testing were done for all people, as advocated by the US Centers for Disease Control and Prevention guidelines,8 more cases could be diagnosed, behaviors changed, and treatment offered. Control of HIV through treatment can lead to a 96% reduction in transmission between serodiscordant partners, as demonstrated in HPTN 052, an ongoing phase 3 trial.9 Early diagnosis and treatment offer the potential for improved immune regeneration and healthier lives.
PRE-EXPOSURE PROPHYLAXIS
Pre-exposure prophylaxis (PrEP) is one approach to empowering women and preventing HIV infection. Studies have demonstrated the efficacy of this approach, although some studies have not.10,11
An important finding in the failed studies appeared to be a lack of adherence to the regimen.11 Unless taken faithfully, PrEP will not succeed. Additionally, there may be inherent differences in outcomes for unknown reasons. Lack of access to the necessary two-drug combination regimen is another barrier.
PrEP is expensive, requires regular monitoring, and requires patients to remain engaged in medical care. Currently, not all medical programs offer PrEP, and not all insurance policies cover it. Further insight into long-term side effects and complications is needed.
Although PrEP is an attractive concept and a reality for some, it is an incomplete solution to prevention at this time.
MEN AND WOMEN ARE DIFFERENT
Men and women are different physiologically and psychologically. Women typically have a lower body mass, lower bone mass, and higher content of body fat. As a result, women may differ from men in their ability to tolerate medications, and long-term side effects may be more pronounced.
Women are also more likely to place family responsibilities above self-preservation and personal health concerns. As a result, providing for and taking care of their children takes precedence over care of their own health.
Providing care to women presents many challenges and opportunities to improve their health. Health care access, transportation, assistance with child care during medical visits, the availability of counseling to deal with shame, guilt, and depression, and maintaining women within the care system are but a few examples.
AGING WITH HIV: STUDY NEEDED
Antiretroviral therapy has enabled patients to survive and often to reach a normal life expectancy if the infection is diagnosed and treated early. As a result, HIV-associated causes of death have been replaced by non-HIV comorbidities typical of aging, such as cardiovascular disease, organ failure (heart, lung, kidney, liver), non-HIV cancers, and bone disease.
Women face unique aspects of aging with menopause, including an accelerated rate of bone loss resulting in osteoporosis. HIV itself and some antiretroviral drugs may increase the loss of bone mineral density. Alcohol abuse, sedentary lifestyle, smoking, hepatitis C co-infection, and poor nutrition also contribute to this problem. Bone disease and many other aspects of aging and HIV in women require more research and intervention.
Other areas that need to be studied are the unique mucosal immune system of the female genital tract, the interplay of sex hormones and the immune system, the role of genital tract inflammation in increasing the risk of HIV acquisition, sexual violence and HIV acquisition, and the safety and efficacy of PrEP for women. This will require prioritization and ongoing funding, which is becoming scarcer. If there is to be hope of containing this disease, our efforts to understand it must not diminish.
- Short WR, Anderson JR. Caring for women with HIV: unique needs and challenges. Cleve Clin J Med 2014; 81:691–701.
- UNAIDS. Women out loud: how women living with HIV will help the world end AIDS. www.unaids.org/en/media/unaids/contentassets/documents/unaidspublication/2012/20121211_Women_Out_Loud_en.pdf. Accessed October 2, 2014.
- Centers for Disease Control and Prevention (CDC). HIV among women. www.cdc.gov/hiv/risk/gender/women/index.html. Accessed October 2, 2014.
- Hodder SL, Justman J, Hughes JP, et al; HIV Prevention Trials Network 064; Women’s HIV SeroIncidence Study Team. HIV acquisition among women from selected areas of the United States: a cohort study. Ann Intern Med 2013; 158:10–18.
- UNAIDS. Fact Sheet: women, girls, gender equality and HIV. www.unaids.org/en/media/unaids/contentassets/documents/factsheet/2012/20120217_FS_WomenGirls_en.pdf. Accessed October 2, 2014.
- Centers for Disease Control and Prevention (CDC). National intimate partner and sexual violence survey: 2010 summary report. www.cdc.gov/violenceprevention/pdf/nisvs_executive_summary-a.pdf. Accessed October 2, 2014.
- Siemieniuk RA, Krentz HB, Miller P, Woodman K, Ko K, Gill MJ. The clinical implications of high rates of intimate partner violence against HIV-positive women. J Acquir Immune Defic Syndr 2013; 64:32–38.
- Branson BM, Handsfield HH, Lampe MA, et al; Centers for Disease Control and Prevention (CDC). Revised recommendations for HIV testing of adults, adolescents, and pregnant women in health-care settings. MMWR Recomm Rep 2006; 55:1–17.
- Cohen MS, Chen YQ, McCauley M, et al; HPTN 052 Study Team. Prevention of HIV-1 infection with early antiretroviral therapy. N Engl J Med 2011; 365:493–505.
- Grant RM, Lama JR, Anderson PL, et al; iPrEx Study Team. Preexposure chemoprophylaxis for HIV prevention in men who have sex with men. N Engl J Med 2010; 363:2587–2599.
- Haberer JE, Baeten JM, Campbell J, et al. Adherence to antiretroviral prophylaxis for HIV prevention: a substudy cohort within a clinical trial of serodiscordant couples in East Africa. PLoS Med 2013; 10 9:e1001511.
- Short WR, Anderson JR. Caring for women with HIV: unique needs and challenges. Cleve Clin J Med 2014; 81:691–701.
- UNAIDS. Women out loud: how women living with HIV will help the world end AIDS. www.unaids.org/en/media/unaids/contentassets/documents/unaidspublication/2012/20121211_Women_Out_Loud_en.pdf. Accessed October 2, 2014.
- Centers for Disease Control and Prevention (CDC). HIV among women. www.cdc.gov/hiv/risk/gender/women/index.html. Accessed October 2, 2014.
- Hodder SL, Justman J, Hughes JP, et al; HIV Prevention Trials Network 064; Women’s HIV SeroIncidence Study Team. HIV acquisition among women from selected areas of the United States: a cohort study. Ann Intern Med 2013; 158:10–18.
- UNAIDS. Fact Sheet: women, girls, gender equality and HIV. www.unaids.org/en/media/unaids/contentassets/documents/factsheet/2012/20120217_FS_WomenGirls_en.pdf. Accessed October 2, 2014.
- Centers for Disease Control and Prevention (CDC). National intimate partner and sexual violence survey: 2010 summary report. www.cdc.gov/violenceprevention/pdf/nisvs_executive_summary-a.pdf. Accessed October 2, 2014.
- Siemieniuk RA, Krentz HB, Miller P, Woodman K, Ko K, Gill MJ. The clinical implications of high rates of intimate partner violence against HIV-positive women. J Acquir Immune Defic Syndr 2013; 64:32–38.
- Branson BM, Handsfield HH, Lampe MA, et al; Centers for Disease Control and Prevention (CDC). Revised recommendations for HIV testing of adults, adolescents, and pregnant women in health-care settings. MMWR Recomm Rep 2006; 55:1–17.
- Cohen MS, Chen YQ, McCauley M, et al; HPTN 052 Study Team. Prevention of HIV-1 infection with early antiretroviral therapy. N Engl J Med 2011; 365:493–505.
- Grant RM, Lama JR, Anderson PL, et al; iPrEx Study Team. Preexposure chemoprophylaxis for HIV prevention in men who have sex with men. N Engl J Med 2010; 363:2587–2599.
- Haberer JE, Baeten JM, Campbell J, et al. Adherence to antiretroviral prophylaxis for HIV prevention: a substudy cohort within a clinical trial of serodiscordant couples in East Africa. PLoS Med 2013; 10 9:e1001511.
Acute respiratory distress syndrome: Implications of recent studies
Continued progress in understanding the pathophysiology of acute respiratory distress syndrome (ARDS) is translating into changes in the way we diagnose and manage it. Over the past 20 years, low tidal volume,1 positive end-expiratory pressure (PEEP),2 and fluid restriction3 have become the standard of care. A multidisciplinary approach, including targeted use of sedatives, early mobilization, and protocols for weaning from the ventilator, has also brought about substantial changes in ARDS management and its outcomes.4–6
In this article, we review the most relevant articles about ARDS in the last 5 years. We include the new definition of ARDS and studies of ventilatory and nonventilatory therapies that have implications in managing patients with ARDS.
A STANDARDIZED APPROACH
ARDS is characterized by damage to the alveolar architecture, severe hypoxemia, and bilateral parenchymal opacities.
The working definition of ARDS developed in 1994 by the American-European Consensus Conference (AECC) was the basis for enrollment in most of the landmark trials and observational studies over the past 20 years.7,8 However, it was limited in its reliability and validity.
An updated definition
In 2011, the ARDS Definition Task Force, using a novel consensus process, updated the ARDS definition,9 focusing on its feasibility, reliability, and validity in predicting response to therapies and outcomes in ARDS. This new “Berlin” definition is not substantially different from the old, but defines the criteria more specifically:
- Bilateral opacities, unexplained by nodules, atelectasis, or effusion, on chest radiography or computed tomography
- New or worsening respiratory symptoms, or a clinical insult associated with ARDS within 7 days of diagnosis
- Objective assessment of cardiac function (eg, with echocardiography) to exclude cardiogenic pulmonary edema
- Hypoxemia, with a partial pressure of arterial oxygen divided by the percentage of inspired oxygen (PaO2/FiO2 ratio) of 300 mm Hg or less despite noninvasive or invasive mechanical ventilation with PEEP or continuous positive airway pressure (CPAP) of at least 5 cm H2O.
In addition, the new definition classifies the severity of disease on the basis of the degree of hypoxemia, ie, the PaO2/FiO2 ratio:
- Mild: PaO2/FiO2 ratio > 200 and ≤ 300 mm Hg
- Moderate: PaO2/FiO2 ratio > 100 and ≤ 200 mm Hg
- Severe: PaO2/FiO2 ratio ≤ 100 mm Hg.
The term “acute lung injury” has been eliminated, as has the previous criterion of a pulmonary artery wedge pressure of 18 mm Hg or less.
The panel also evaluated four ancillary variables for predicting outcomes in severe ARDS:
- Compliance of the respiratory system less than or equal to 40 mL/cm H2O
- Radiographic severity (involvement of three or four quadrants on chest radiography)
- PEEP of 10 cm H2O or greater
- Corrected expired volume 10 L/min or greater.
The task force evaluated the reliability and validity of this definition in a meta-analysis of 4,400 patients previously enrolled in randomized controlled trials or observational studies.
Findings. The Berlin definition predicted the risk of death better than the AECC definition. The mortality rate increased with the severity of ARDS, from 27% with mild disease to 32% with moderate disease to 45% with severe disease. The four ancillary variables did not contribute to the predictive validity of severe ARDS for mortality and were removed from the definition.
Thille et al10 retrospectively reviewed autopsy findings from 712 patients and found that the new definition identified a homogeneous group who had severe ARDS.10
Conclusions. The new definition may overcome some of the limitations of the old one, but it needs to be validated in clinical practice, especially its ability to predict death.
VENTILATORY SUPPORT
Prompt recognition, lung-protective ventilation, and a conservative fluid strategy remain the cornerstones of ARDS management. However, other strategies are being tested.
Prone-position ventilation in severe ARDS: The right therapy in a specific population
Prone-position ventilation was first described almost 30 years ago, but it has been used inconsistently in clinical practice.
Physiologic and observational studies indicated that prone positioning might improve survival in patients with ARDS, but several randomized trials failed to demonstrate any positive effect on outcomes.11,12 Some trials also reported a higher rate of complications with this intervention.13 However, meta-analyses suggested that prone-position ventilation might have a beneficial effect in patients with severe ARDS (defined as a PaO2/FiO2 ratio ≤ 100 mm Hg).14
In view of these findings, investigators conducted a trial of prone-position ventilation exclusively in patients with severe ARDS.
The PROSEVA study
The Proning Severe ARDS Patients (PROSEVA) study was a randomized controlled trial designed to determine whether prone-position ventilation, applied early, would improve outcomes in patients with severe ARDS.15
In PROSEVA, 466 patients with severe ARDS (defined as a PaO2/FiO2 ratio < 150 mm Hg, FiO2 ≥ 60%, and PEEP ≥ 5 cm H2O) underwent either at least 16 hours of prone positioning or were left in the supine position after 12 to 24 hours of initial conventional mechanical ventilation. The patients were recruited from centers in France and Spain where prone-position ventilation had been used in daily practice for more than 5 years.
The primary outcome studied was the rate of death at 28 days. The secondary end points were the death rate at day 90, rates of successful extubation, the length of stay in the intensive care unit, and complications.
Findings. At study entry, the patients in the supine group were sicker, more of them required a vasopressor, and fewer of them were receiving neuromuscular blocking agents than those in the prone group. These baseline differences may have influenced the outcomes; the unadjusted 28-day mortality rate was 16.0% in the prone group compared with 32.8% in the supine group (P < .001). However, the hazard ratio for death with prone positioning was 0.39 (95% confidence interval [CI] 0.25–0.63) even after adjusting for severity and the use of vasopressors and neuromuscular blocking agents. Prone-position ventilation was not associated with a higher incidence of complications, and the rate of successful extubation was higher.
Conclusions. In patients with severe ARDS, early use of prolonged prone positioning significantly decreased the 28-day and 90-day mortality rates. This trial has made prone positioning one of the strategies in managing patients with early severe ARDS. To minimize complications such as pressure ulcers and line or tube dislodgement, personnel caring for these patients must follow a protocol and undergo specific training.
These results were corroborated by a meta-analysis by Beitler et al16 that found a significant decrease in mortality rate with prone-position ventilation even in older studies when lung-protective ventilation strategies were separated from high-tidal-volume ventilation.
High-frequency oscillatory ventilation: No benefit in two trials
Observational data and experimental studies suggested that high-frequency oscillatory ventilation (HFOV) is superior to conventional mechanical ventilation in ARDS patients.17,18 However, outdated and cumbersome equipment, lack of protocols, and a lack of high-quality evidence led to limited and inconsistent use of HFOV, mainly as a rescue therapy in ARDS.19
Over the last few years, HFOV has been gaining acceptance, especially earlier in the course of ARDS.20 After preliminary clinical trials reported promising results, two trials conducted in Canada and the United Kingdom compared HFOV vs conventional mechanical ventilation in patients with ARDS.
The OSCAR study
The Oscillation in ARDS (OSCAR) study21 was a “pragmatic” trial22 (ie, it had minimal exclusion criteria) of the safety and effectiveness of HFOV as a primary ventilatory strategy for ARDS. It included 795 patients randomized to receive conventional ventilation (n = 397) or HFOV (n = 398). Research centers followed detailed algorithms for HFOV management and adopted their usual practice for conventional ventilation. Medical care was given according to the clinician’s judgment.
The primary outcome studied was survival at 30 days. The secondary outcomes were all-cause mortality in the intensive care unit and the hospital, duration of mechanical ventilation, and use of antimicrobial, sedative, vasoactive, and neuromuscular-blocking drugs.
Findings. The patient baseline characteristics were similar in both groups.
There was no significant difference in intensive care unit mortality rates, hospital mortality rates, or mortality rates at 30 days (41.7% in the HFOV group vs 41.1% in the conventional ventilation group; P = .85, 95% CI 6.1–7.5) even after adjustments for center or severity of illness.
The duration of mechanical ventilation was similar in both groups (14.9 ± 13.3 days in the HFOV group vs 14.1 ± 13.4 days in the conventional ventilation group, P = .41). However, sedatives and neuromuscular-blocking drugs were used more often and longer in the HFOV group than in the conventional ventilation group. There was no difference in the use of vasoactive or antimicrobial medications.
Conclusions. This multicenter randomized control trial did not demonstrate any benefit from using HFOV for routine management of ARDS. Its pragmatic design made it less likely to reach a firm conclusion,22 but it at least made a case against routinely using HFOV in patients with ARDS.
The OSCILLATE study
The Oscillation for Acute Respiratory Distress Syndrome Treated Early (OSCILLATE) study23 assessed the safety and efficacy of HFOV as a treatment for early-onset moderate-to-severe ARDS.
The inclusion criteria were similar to those in the OSCAR trial except that pulmonary symptoms had to be present less than 2 weeks and ARDS assessment was done under standard ventilator settings. As this was an efficacy trial, it had more exclusion criteria than the OSCAR trial. A total of 548 patients were randomized to receive conventional ventilation (n = 273) or HFOV (n = 275). The baseline characteristics were similar between groups.
Conventional ventilation was given according to a protocol used in an earlier trial2 and included recruitment maneuvers. HFOV was given in centers that had experience in this treatment, and there were protocols for ventilation management, hemodynamic optimization, and weaning. All other care was left to the clinician’s choice.
The primary outcome studied was in-hospital mortality. The investigators also evaluated whether there were interactions between the treatment and baseline severity of lung injury and center experience with HFOV.
Findings. The trial was stopped after an interim analysis found that HFOV might be harmful, although the statistical threshold for stopping was not reached. The in-hospital mortality rate was 47% in the HFOV group and 35% in the control group (relative risk of death with HFOV 1.33, 95% CI 1.09–1.64, P = .005). HFOV was worse than conventional ventilation regardless of the severity of disease or center experience. The HFOV group had higher mean airway pressures but similar FiO2 compared with the conventional ventilation group.
The HFOV group received significantly more vasopressors, sedatives, and neuromuscular blockers. This group’s fluid balance was higher as well, but not significantly so. Refractory hypoxemia (defined as PaO2 < 60 mm Hg for 1 hour with an FiO2 of 1.0 and neuromuscular blockade) was more frequent in the conventional ventilation group, but the number of deaths in the subgroup with refractory hypoxemia was similar with either treatment.
Conclusions. This multicenter randomized controlled trial demonstrated that HFOV was harmful when used routinely to manage ARDS. The trial’s protocol was based on the results of a pilot study carried out by the same investigators, which provided the best evidence available regarding the safety of HFOV at that time.
The results of the OSCAR and OSCILLATE trials have quelled enthusiasm for early, routine use of HFOV in ARDS. Although there are concerns that the protocol (ie, the way HFOV was implemented) rather than HFOV itself may have led to worse outcomes, there is no signal to support its routine use. We need further studies to define if it remains a viable rescue therapy.
Extracorporeal membrane oxygenation: Is it a viable option in severe ARDS?
Extracorporeal membrane oxygenation (ECMO) uses cardiopulmonary bypass technology to provide gas exchange. In patients with severe hypoxemia, ECMO can ensure adequate oxygenation and ventilation while ensuring the optimization of lung-protective ventilation. But ECMO was never as successful in adults with ARDS as it was in children and neonates.24
The first two trials of ECMO in ARDS24,25 reported equal or worse survival rates compared with conventional ventilation, and the overall mortality rate in these studies was staggeringly high. However, these studies were carried out before the era of lung-protective ventilation and at a time when ECMO technology was relatively primitive.
With new technology such as venovenous circuits and smaller cannulas, ECMO has gained more acceptance. It was used in patients with severe or refractory hypoxemia associated with ARDS during the H1N1 pandemic.26,27
The CESAR trial
The Conventional Ventilatory Support Versus Extracorporeal Membrane Oxygenation for Severe Adult Respiratory Failure (CESAR) trial28 assessed the safety, clinical efficacy, and cost-effectiveness of ECMO in managing severe ARDS. It compared best standard practice vs a protocol that included ECMO. The trial was conducted from 2001 to 2006.
Patients with severe ARDS, as defined by a Murray score29 greater than 3 or uncompensated hypercapnea, were prospectively randomized and recruited from an ECMO center and 148 tertiary intensive care units and referral hospitals in England. This was a pragmatic trial, with minimal exclusion criteria (essentially, mechanical ventilation with high pressures and high FiO2 for more than 7 days, intracranial bleeding, or contraindication to heparinization).
A total of 180 patients were randomized in a one-to-one ratio to receive ECMO or conventional management. The ventilator management in the conventional treatment group was not done according to a protocol but in general was low-volume and low-pressure. All patients randomized to ECMO were transferred to the ECMO center and treated according to a standardized ventilation protocol. After 12 hours, if predefined goals were not reached, venovenous ECMO was started. Patients assigned to conventional management could not cross over to ECMO.
The primary outcomes were death or severe disability at 6 months after randomization, and cost-effectiveness. The secondary outcomes were hospital resource use (eg, rescue techniques, length of stay, duration of ECMO) and health status after 6 months.
Findings. The groups were similar at baseline. Sixty-eight (75%) of the 90 patients randomized to receive ECMO actually received it. Of the 22 patients who did not receive ECMO, 16 (18% of the 90) improved on conventional therapy, 5 (6%) died during or before transfer, and 1 could not receive heparin.
Two patients had severe complications in the ECMO group: one had an arterial puncture, and one had an oxygen delivery failure during transport. In each case, these events contributed to the death of the patient.
More patients in the ECMO group received lung-protective ventilation, 84 (93%) vs 63 (70%).
The primary outcome, ie, death or severe disability at 6 months, occurred in 33 (37%) of the 90 patients in the ECMO group and in 46 (53%) of the patients in the conventional management group (relative risk 0.69, 95% CI 0.05–0.97, P = .03). More patients in the ECMO group survived, but the difference was not statistically significant (relative risk of death 0.73, 95% CI 0.52–1.03, P = .07). The most common cause of death in the ECMO group was multiorgan failure (42%), whereas in the conventional management group, the most common cause of death was respiratory failure (60%).
Length of stay in the hospital and in the critical care unit and health care costs were double for patients in the ECMO group. There was no difference in quality-of-life markers at 6 months in the survivors.
Conclusions. This pragmatic trial demonstrated that a protocol that includes ECMO could improve survival rates in ARDS.
Of note, the ECMO group got care in regional centers that used protocols. Therefore, in interpreting the results of this trial, we have to consider that being in a center with protocol-specified care for ARDS could drive some of the difference in mortality rates.
Regardless, this trial demonstrated that ECMO is feasible and led to better outcomes than expected. The findings were encouraging, and spurred the use of ECMO in severe ARDS during the 2009 H1N1 pandemic. Two propensity-matched studies and a number of case series reported a survival benefit associated with the use of ECMO in patients with severe ARDS.27,30
A recent meta-analysis also reported that ECMO might lower the mortality rate in ARDS; however, the patients in the H1N1 pandemic were younger and usually had isolated respiratory failure.31
The success of ECMO has opened new possibilities in the management of ARDS. As the technology improves and our experience increases, ECMO will likely gain more acceptance as a treatment for severe ARDS.
Airway pressure release ventilation
The use of airway pressure release ventilation and other ventilator modalities in ARDS is not supported by current evidence, though results of clinical trials may influence our practice in the future.
PHARMACOTHERAPY IN ARDS
The pathogenesis of ARDS includes damage to the alveolar-capillary membrane, with leakage of protein-rich edema fluid into alveoli. This damage is propagated by a complex inflammatory response including but not limited to neutrophil activation, free-radical formation, dysregulation of the coagulation system, and extensive release of inflammatory mediators.32,33 As a consequence, there are multiple potential targets for pharmacologic therapy in ARDS.
A variety of drugs, including corticosteroids, anti-inflammatory agents, immune-modulating agents, pulmonary vasodilators, antioxidants, and surfactants, have been studied in patients with ARDS.34 But effective pharmacotherapy for ARDS remains extremely limited.
Neuromuscular blockade in early severe ARDS
Mechanical ventilation can result in injurious stretching of the lung parenchyma, either from alveolar overdistention (volutrauma) or from continual recruitment and derecruitment of unstable lung units during the ventilator cycle (atelectrauma).35 Ventilator-induced lung injury can be exacerbated by asynchronous breathing.
In theory, neuromuscular blockers could minimize patient-ventilator asynchrony and provide much better control of tidal volume and pressure in patients with ARDS. This may result in less volutrauma and atelectrauma associated with asynchronous breathing. Data also suggest that cisatracurium (Nimbex), a neuromuscular blocking agent, may have a direct effect on the amount of inflammation in lungs with ARDS.36
The ACURASYS study
The ARDS et Curarisation Systématique (ACURASYS) study37 was a randomized trial in 340 patients undergoing mechanical ventilation for severe ARDS to evaluate the impact of neuromuscular blockade within the first 48 hours in this population.
The primary outcome was the mortality rate before hospital discharge or within 90 days of study entry. Secondary outcomes included the 28-day mortality rate, the rate of intensive care unit-acquired paresis, and the number of ventilator-free days. To be included, patients had to have been mechanically ventilated for less than 48 hours and to meet the AECC criteria for severe ARDS, with a PaO2/FiO2 ratio less than 150 mm Hg.
The intervention group received a continuous infusion of cisatracurium for 48 hours, while the control patients received placebo. Muscle strength was evaluated by clinical scoring of strength in different muscle groups.
Findings. The study groups were similar at baseline.
The crude 90-day mortality rate was lower in the cisatracurium group (31.6% vs 40.7%, P = .08). Regression analysis showed an improved 90-day survival rate with the use of this neuromuscular blocker after adjustment for severity of illness and the severity of ARDS (based on degree of hypoxemia and plateau pressures) (hazard ratio for death at 90 days 0.68; 95% CI 0.48–0.98; P = .04). The rate of paresis acquired in the intensive care unit did not differ significantly between the two groups.
Conclusion. In patients with severe ARDS, giving a neuromuscular blocking agent early improved the survival rate and increased the time off the ventilator without increasing muscle weakness.
These data are in line with similar findings from two other studies published by the same group.38,39 A meta-analysis of 432 patients showed that the use of neuromuscular blockade in early severe ARDS is associated with a statistically significant effect on early mortality (relative risk 0.66, 95% CI 0.50–0.87).40 The pooled analysis of these trials did not show any statistically significant critical-illness polyneuropathy.
These results need to be interpreted carefully, as we have inadequate data to see if they generalize to different intensive care units, and the evaluation and categorization of critical-illness polyneuropathy remains to be defined.
Cisatracurium is a promising treatment for moderate to severe ARDS and merits investigation in a large confirmatory randomized controlled trial.
Other pharmacologic agents
A number of other drugs have been studied in ARDS patients, including both inhaled and intravenous beta agonists,41,42 statins,43 and nutritional supplements.44 But as with other drugs previously studied in ARDS such as corticosteroids, N-acetylcysteine, and surfactant,34 these agents showed no effect on outcomes. In fact, a recent trial of intravenous salbutamol in ARDS patients was stopped after an interim analysis because of a higher incidence of arrhythmias and lactic acidosis with this agent.42
These findings reaffirm that pharmacologic therapy needs to be carefully considered, and potential harms associated with these therapies need to be addressed before they are introduced in the care of critically ill patients.
- Ventilation with lower tidal volumes as compared with traditional tidal volumes for acute lung injury and the acute respiratory distress syndrome. Acute Respiratory Distress Syndrome Network. N Engl J Med 2000; 342:1301–1308.
- Meade MO, Cook DJ, Guyatt GH, et al; Lung Open Ventilation Study Investigators. Ventilation strategy using low tidal volumes, recruitment maneuvers, and high positive end-expiratory pressure for acute lung injury and acute respiratory distress syndrome: a randomized controlled trial. JAMA 2008; 299:637–645.
- National Heart, Lung, and Blood Institute Acute Respiratory Distress Syndrome (ARDS) Clinical Trials Network; Wiedemann HP, Wheeler AP, Bernard GR, et al. Comparison of two fluid-management strategies in acute lung injury. N Engl J Med 2006; 354:2564–2575.
- Girard TD, Kress JP, Fuchs BD, et al. Efficacy and safety of a paired sedation and ventilator weaning protocol for mechanically ventilated patients in intensive care (Awakening and Breathing Controlled trial): a randomised controlled trial. Lancet 2008; 371:126–134.
- Schweickert WD, Pohlman MC, Pohlman AS, et al. Early physical and occupational therapy in mechanically ventilated, critically ill patients: a randomised controlled trial. Lancet 2009; 373:1874–1882.
- Ely EW, Baker AM, Dunagan DP, et al. Effect on the duration of mechanical ventilation of identifying patients capable of breathing spontaneously. N Engl J Med 1996; 335:1864–1869.
- Bernard GR, Artigas A, Brigham KL, et al. The American-European Consensus Conference on ARDS. Definitions, mechanisms, relevant outcomes, and clinical trial coordination. Am J Respir Crit Care Med 1994; 149:818–824.
- Ferguson ND, Fan E, Camporota L, et al. The Berlin definition of ARDS: an expanded rationale, justification, and supplementary material. Intensive Care Med 2012; 38:1573–1582.
- ARDS Definition Task Force; Ranieri VM, Rubenfeld GD, Thompson BT, et al. Acute respiratory distress syndrome: the Berlin definition. JAMA 2012; 307:2526–2533.
- Thille AW, Esteban A, Fernández-Segoviano P, et al. Comparison of the Berlin definition for acute respiratory distress syndrome with autopsy. Am J Respir Crit Care Med 2013; 187:761–767.
- Gattinoni L, Tognoni G, Pesenti A, et al; Prone-Supine Study Group. Effect of prone positioning on the survival of patients with acute respiratory failure. N Engl J Med 2001; 345:568–573.
- Taccone P, Pesenti A, Latini R, et al; Prone-Supine II Study Group. Prone positioning in patients with moderate and severe acute respiratory distress syndrome: a randomized controlled trial. JAMA 2009; 302:1977–1984.
- Mancebo J, Fernández R, Blanch L, et al. A multicenter trial of prolonged prone ventilation in severe acute respiratory distress syndrome. Am J Respir Crit Care Med 2006; 173:1233–1239.
- Sud S, Friedrich JO, Taccone P, et al. Prone ventilation reduces mortality in patients with acute respiratory failure and severe hypoxemia: systematic review and meta-analysis. Intensive Care Med 2010; 36:585–599.
- Guérin C, Reignier J, Richard JC, et al; PROSEVA Study Group. Prone positioning in severe acute respiratory distress syndrome. N Engl J Med 2013; 368:2159–2168.
- Beitler JR, Shaefi S, Montesi SB, et al. Prone positioning reduces mortality from acute respiratory distress syndrome in the low tidal volume era: a meta-analysis. Intensive Care Med 2014; 40:332–341.
- Chan KP, Stewart TE, Mehta S. High-frequency oscillatory ventilation for adult patients with ARDS. Chest 2007; 131:1907–1916.
- Fessler HE, Hager DN, Brower RG. Feasibility of very high-frequency ventilation in adults with acute respiratory distress syndrome. Crit Care Med 2008; 36:1043–1048.
- Mehta S, Granton J, MacDonald RJ, et al. High-frequency oscillatory ventilation in adults: the Toronto experience. Chest 2004; 126:518–527.
- Ferguson ND, Chiche JD, Kacmarek RM, et al. Combining high-frequency oscillatory ventilation and recruitment maneuvers in adults with early acute respiratory distress syndrome: the Treatment with Oscillation and an Open Lung Strategy (TOOLS) Trial pilot study. Crit Care Med 2005; 33:479–486.
- Young D, Lamb SE, Shah S, et al; OSCAR Study Group. High-frequency oscillation for acute respiratory distress syndrome. N Engl J Med 2013; 368:806–813.
- Thorpe KE, Zwarenstein M, Oxman AD, et al. A pragmatic-explanatory continuum indicator summary (PRECIS): a tool to help trial designers. J Clin Epidemiol 2009; 62:464–475.
- Ferguson ND, Cook DJ, Guyatt GH, et al; OSCILLATE Trial Investigators; Canadian Critical Care Trials Group. High-frequency oscillation in early acute respiratory distress syndrome. N Engl J Med 2013; 368:795–805.
- Morris AH, Wallace CJ, Menlove RL, et al. Randomized clinical trial of pressure-controlled inverse ratio ventilation and extracorporeal CO2 removal for adult respiratory distress syndrome. Am J Respir Crit Care Med 1994; 149:295–305.
- Zapol WM, Snider MT, Hill JD, et al. Extracorporeal membrane oxygenation in severe acute respiratory failure. A randomized prospective study. JAMA 1979; 242:2193–2196.
- Australia and New Zealand Extracorporeal Membrane Oxygenation (ANZ ECMO) Influenza Investigators; Davies A, Jones D, Bailey M, et al. Extracorporeal Membrane Oxygenation for 2009 Influenza A(H1N1) Acute Respiratory Distress Syndrome. JAMA 2009; 302:1888–1895.
- Pham T, Combes A, Rozé H, et al; REVA Research Network. Extracorporeal membrane oxygenation for pandemic influenza A(H1N1)-induced acute respiratory distress syndrome: a cohort study and propensity-matched analysis. Am J Respir Crit Care Med 2013; 187:276–285.
- Peek GJ, Mugford M, Tiruvoipati R, et al; CESAR trial collaboration. Efficacy and economic assessment of conventional ventilatory support versus extracorporeal membrane oxygenation for severe adult respiratory failure (CESAR): a multicentre randomised controlled trial. Lancet 2009; 374:1351–1363.
- Murray JF, Matthay MA, Luce JM, Flick MR. An expanded definition of the adult respiratory distress syndrome. Am Rev Respir Dis 1988; 138:720–723.
- Noah MA, Peek GJ, Finney SJ, et al. Referral to an extracorporeal membrane oxygenation center and mortality among patients with severe 2009 influenza A(H1N1). JAMA 2011; 306:1659–1668.
- Zampieri FG, Mendes PV, Ranzani OT, et al. Extracorporeal membrane oxygenation for severe respiratory failure in adult patients: a systematic review and meta-analysis of current evidence. J Crit Care 2013; 28:998–1005.
- Raghavendran K, Pryhuber GS, Chess PR, Davidson BA, Knight PR, Notter RH. Pharmacotherapy of acute lung injury and acute respiratory distress syndrome. Curr Med Chem 2008; 15:1911–1924.
- Adhikari N, Burns KE, Meade MO. Pharmacologic treatments for acute respiratory distress syndrome and acute lung injury: systematic review and meta-analysis. Treat Respir Med 2004; 3:307–328.
- Adhikari N, Burns KE, Meade MO. Pharmacologic therapies for adults with acute lung injury and acute respiratory distress syndrome. Cochrane Database Syst Rev 2004; 4:CD004477.
- Terragni PP, Rosboch GL, Lisi A, Viale AG, Ranieri VM. How respiratory system mechanics may help in minimising ventilator-induced lung injury in ARDS patients. Eur Respir J Suppl 2003; 42:15s–21s.
- Forel JM, Roch A, Papazian L. Paralytics in critical care: not always the bad guy. Curr Opin Crit Care 2009; 15:59–66.
- Papazian L, Forel JM, Gacouin A, et al; ACURASYS Study Investigators. Neuromuscular blockers in early acute respiratory distress syndrome. N Engl J Med 2010; 363:1107–1116.
- Gainnier M, Roch A, Forel JM, et al. Effect of neuromuscular blocking agents on gas exchange in patients presenting with acute respiratory distress syndrome. Crit Care Med 2004; 32:113–19.
- Forel JM, Roch A, Marin V, et al. Neuromuscular blocking agents decrease inflammatory response in patients presenting with acute respiratory distress syndrome. Crit Care Med 2006; 34:2749–2757.
- Alhazzani W, Alshahrani M, Jaeschke R, et al. Neuromuscular blocking agents in acute respiratory distress syndrome: a systematic review and meta-analysis of randomized controlled trials. Crit Care 2013; 17:R43.
- National Heart, Lung, and Blood Institute Acute Respiratory Distress Syndrome (ARDS) Clinical Trials Network; Matthay MA, Brower RG, Carson S, et al. Randomized, placebo-controlled clinical trial of an aerosolized beta-2-agonist for treatment of acute lung injury. Am J Respir Crit Care Med 2011; 184:561–568.
- Gao Smith F, Perkins GD, Gates S, et al; BALTI-2 study investigators. Effect of intravenous beta-2 agonist treatment on clinical outcomes in acute respiratory distress syndrome (BALTI-2): a multicentre, randomised controlled trial. Lancet 2012; 379:229–235.
- Craig TR, Duffy MJ, Shyamsundar M, et al. A randomized clinical trial of hydroxymethylglutaryl-coenzyme a reductase inhibition for acute lung injury (The HARP Study). Am J Respir Crit Care Med 2011; 183:620–626.
- National Heart, Lung, and Blood Institute Acute Respiratory Distress Syndrome (ARDS) Clinical Trials Network; Rice TW, Wheeler AP, Thompson BT, et al. Initial trophic vs full enteral feeding in patients with acute lung injury: the EDEN randomized trial. JAMA 2012; 307:795–803.
Continued progress in understanding the pathophysiology of acute respiratory distress syndrome (ARDS) is translating into changes in the way we diagnose and manage it. Over the past 20 years, low tidal volume,1 positive end-expiratory pressure (PEEP),2 and fluid restriction3 have become the standard of care. A multidisciplinary approach, including targeted use of sedatives, early mobilization, and protocols for weaning from the ventilator, has also brought about substantial changes in ARDS management and its outcomes.4–6
In this article, we review the most relevant articles about ARDS in the last 5 years. We include the new definition of ARDS and studies of ventilatory and nonventilatory therapies that have implications in managing patients with ARDS.
A STANDARDIZED APPROACH
ARDS is characterized by damage to the alveolar architecture, severe hypoxemia, and bilateral parenchymal opacities.
The working definition of ARDS developed in 1994 by the American-European Consensus Conference (AECC) was the basis for enrollment in most of the landmark trials and observational studies over the past 20 years.7,8 However, it was limited in its reliability and validity.
An updated definition
In 2011, the ARDS Definition Task Force, using a novel consensus process, updated the ARDS definition,9 focusing on its feasibility, reliability, and validity in predicting response to therapies and outcomes in ARDS. This new “Berlin” definition is not substantially different from the old, but defines the criteria more specifically:
- Bilateral opacities, unexplained by nodules, atelectasis, or effusion, on chest radiography or computed tomography
- New or worsening respiratory symptoms, or a clinical insult associated with ARDS within 7 days of diagnosis
- Objective assessment of cardiac function (eg, with echocardiography) to exclude cardiogenic pulmonary edema
- Hypoxemia, with a partial pressure of arterial oxygen divided by the percentage of inspired oxygen (PaO2/FiO2 ratio) of 300 mm Hg or less despite noninvasive or invasive mechanical ventilation with PEEP or continuous positive airway pressure (CPAP) of at least 5 cm H2O.
In addition, the new definition classifies the severity of disease on the basis of the degree of hypoxemia, ie, the PaO2/FiO2 ratio:
- Mild: PaO2/FiO2 ratio > 200 and ≤ 300 mm Hg
- Moderate: PaO2/FiO2 ratio > 100 and ≤ 200 mm Hg
- Severe: PaO2/FiO2 ratio ≤ 100 mm Hg.
The term “acute lung injury” has been eliminated, as has the previous criterion of a pulmonary artery wedge pressure of 18 mm Hg or less.
The panel also evaluated four ancillary variables for predicting outcomes in severe ARDS:
- Compliance of the respiratory system less than or equal to 40 mL/cm H2O
- Radiographic severity (involvement of three or four quadrants on chest radiography)
- PEEP of 10 cm H2O or greater
- Corrected expired volume 10 L/min or greater.
The task force evaluated the reliability and validity of this definition in a meta-analysis of 4,400 patients previously enrolled in randomized controlled trials or observational studies.
Findings. The Berlin definition predicted the risk of death better than the AECC definition. The mortality rate increased with the severity of ARDS, from 27% with mild disease to 32% with moderate disease to 45% with severe disease. The four ancillary variables did not contribute to the predictive validity of severe ARDS for mortality and were removed from the definition.
Thille et al10 retrospectively reviewed autopsy findings from 712 patients and found that the new definition identified a homogeneous group who had severe ARDS.10
Conclusions. The new definition may overcome some of the limitations of the old one, but it needs to be validated in clinical practice, especially its ability to predict death.
VENTILATORY SUPPORT
Prompt recognition, lung-protective ventilation, and a conservative fluid strategy remain the cornerstones of ARDS management. However, other strategies are being tested.
Prone-position ventilation in severe ARDS: The right therapy in a specific population
Prone-position ventilation was first described almost 30 years ago, but it has been used inconsistently in clinical practice.
Physiologic and observational studies indicated that prone positioning might improve survival in patients with ARDS, but several randomized trials failed to demonstrate any positive effect on outcomes.11,12 Some trials also reported a higher rate of complications with this intervention.13 However, meta-analyses suggested that prone-position ventilation might have a beneficial effect in patients with severe ARDS (defined as a PaO2/FiO2 ratio ≤ 100 mm Hg).14
In view of these findings, investigators conducted a trial of prone-position ventilation exclusively in patients with severe ARDS.
The PROSEVA study
The Proning Severe ARDS Patients (PROSEVA) study was a randomized controlled trial designed to determine whether prone-position ventilation, applied early, would improve outcomes in patients with severe ARDS.15
In PROSEVA, 466 patients with severe ARDS (defined as a PaO2/FiO2 ratio < 150 mm Hg, FiO2 ≥ 60%, and PEEP ≥ 5 cm H2O) underwent either at least 16 hours of prone positioning or were left in the supine position after 12 to 24 hours of initial conventional mechanical ventilation. The patients were recruited from centers in France and Spain where prone-position ventilation had been used in daily practice for more than 5 years.
The primary outcome studied was the rate of death at 28 days. The secondary end points were the death rate at day 90, rates of successful extubation, the length of stay in the intensive care unit, and complications.
Findings. At study entry, the patients in the supine group were sicker, more of them required a vasopressor, and fewer of them were receiving neuromuscular blocking agents than those in the prone group. These baseline differences may have influenced the outcomes; the unadjusted 28-day mortality rate was 16.0% in the prone group compared with 32.8% in the supine group (P < .001). However, the hazard ratio for death with prone positioning was 0.39 (95% confidence interval [CI] 0.25–0.63) even after adjusting for severity and the use of vasopressors and neuromuscular blocking agents. Prone-position ventilation was not associated with a higher incidence of complications, and the rate of successful extubation was higher.
Conclusions. In patients with severe ARDS, early use of prolonged prone positioning significantly decreased the 28-day and 90-day mortality rates. This trial has made prone positioning one of the strategies in managing patients with early severe ARDS. To minimize complications such as pressure ulcers and line or tube dislodgement, personnel caring for these patients must follow a protocol and undergo specific training.
These results were corroborated by a meta-analysis by Beitler et al16 that found a significant decrease in mortality rate with prone-position ventilation even in older studies when lung-protective ventilation strategies were separated from high-tidal-volume ventilation.
High-frequency oscillatory ventilation: No benefit in two trials
Observational data and experimental studies suggested that high-frequency oscillatory ventilation (HFOV) is superior to conventional mechanical ventilation in ARDS patients.17,18 However, outdated and cumbersome equipment, lack of protocols, and a lack of high-quality evidence led to limited and inconsistent use of HFOV, mainly as a rescue therapy in ARDS.19
Over the last few years, HFOV has been gaining acceptance, especially earlier in the course of ARDS.20 After preliminary clinical trials reported promising results, two trials conducted in Canada and the United Kingdom compared HFOV vs conventional mechanical ventilation in patients with ARDS.
The OSCAR study
The Oscillation in ARDS (OSCAR) study21 was a “pragmatic” trial22 (ie, it had minimal exclusion criteria) of the safety and effectiveness of HFOV as a primary ventilatory strategy for ARDS. It included 795 patients randomized to receive conventional ventilation (n = 397) or HFOV (n = 398). Research centers followed detailed algorithms for HFOV management and adopted their usual practice for conventional ventilation. Medical care was given according to the clinician’s judgment.
The primary outcome studied was survival at 30 days. The secondary outcomes were all-cause mortality in the intensive care unit and the hospital, duration of mechanical ventilation, and use of antimicrobial, sedative, vasoactive, and neuromuscular-blocking drugs.
Findings. The patient baseline characteristics were similar in both groups.
There was no significant difference in intensive care unit mortality rates, hospital mortality rates, or mortality rates at 30 days (41.7% in the HFOV group vs 41.1% in the conventional ventilation group; P = .85, 95% CI 6.1–7.5) even after adjustments for center or severity of illness.
The duration of mechanical ventilation was similar in both groups (14.9 ± 13.3 days in the HFOV group vs 14.1 ± 13.4 days in the conventional ventilation group, P = .41). However, sedatives and neuromuscular-blocking drugs were used more often and longer in the HFOV group than in the conventional ventilation group. There was no difference in the use of vasoactive or antimicrobial medications.
Conclusions. This multicenter randomized control trial did not demonstrate any benefit from using HFOV for routine management of ARDS. Its pragmatic design made it less likely to reach a firm conclusion,22 but it at least made a case against routinely using HFOV in patients with ARDS.
The OSCILLATE study
The Oscillation for Acute Respiratory Distress Syndrome Treated Early (OSCILLATE) study23 assessed the safety and efficacy of HFOV as a treatment for early-onset moderate-to-severe ARDS.
The inclusion criteria were similar to those in the OSCAR trial except that pulmonary symptoms had to be present less than 2 weeks and ARDS assessment was done under standard ventilator settings. As this was an efficacy trial, it had more exclusion criteria than the OSCAR trial. A total of 548 patients were randomized to receive conventional ventilation (n = 273) or HFOV (n = 275). The baseline characteristics were similar between groups.
Conventional ventilation was given according to a protocol used in an earlier trial2 and included recruitment maneuvers. HFOV was given in centers that had experience in this treatment, and there were protocols for ventilation management, hemodynamic optimization, and weaning. All other care was left to the clinician’s choice.
The primary outcome studied was in-hospital mortality. The investigators also evaluated whether there were interactions between the treatment and baseline severity of lung injury and center experience with HFOV.
Findings. The trial was stopped after an interim analysis found that HFOV might be harmful, although the statistical threshold for stopping was not reached. The in-hospital mortality rate was 47% in the HFOV group and 35% in the control group (relative risk of death with HFOV 1.33, 95% CI 1.09–1.64, P = .005). HFOV was worse than conventional ventilation regardless of the severity of disease or center experience. The HFOV group had higher mean airway pressures but similar FiO2 compared with the conventional ventilation group.
The HFOV group received significantly more vasopressors, sedatives, and neuromuscular blockers. This group’s fluid balance was higher as well, but not significantly so. Refractory hypoxemia (defined as PaO2 < 60 mm Hg for 1 hour with an FiO2 of 1.0 and neuromuscular blockade) was more frequent in the conventional ventilation group, but the number of deaths in the subgroup with refractory hypoxemia was similar with either treatment.
Conclusions. This multicenter randomized controlled trial demonstrated that HFOV was harmful when used routinely to manage ARDS. The trial’s protocol was based on the results of a pilot study carried out by the same investigators, which provided the best evidence available regarding the safety of HFOV at that time.
The results of the OSCAR and OSCILLATE trials have quelled enthusiasm for early, routine use of HFOV in ARDS. Although there are concerns that the protocol (ie, the way HFOV was implemented) rather than HFOV itself may have led to worse outcomes, there is no signal to support its routine use. We need further studies to define if it remains a viable rescue therapy.
Extracorporeal membrane oxygenation: Is it a viable option in severe ARDS?
Extracorporeal membrane oxygenation (ECMO) uses cardiopulmonary bypass technology to provide gas exchange. In patients with severe hypoxemia, ECMO can ensure adequate oxygenation and ventilation while ensuring the optimization of lung-protective ventilation. But ECMO was never as successful in adults with ARDS as it was in children and neonates.24
The first two trials of ECMO in ARDS24,25 reported equal or worse survival rates compared with conventional ventilation, and the overall mortality rate in these studies was staggeringly high. However, these studies were carried out before the era of lung-protective ventilation and at a time when ECMO technology was relatively primitive.
With new technology such as venovenous circuits and smaller cannulas, ECMO has gained more acceptance. It was used in patients with severe or refractory hypoxemia associated with ARDS during the H1N1 pandemic.26,27
The CESAR trial
The Conventional Ventilatory Support Versus Extracorporeal Membrane Oxygenation for Severe Adult Respiratory Failure (CESAR) trial28 assessed the safety, clinical efficacy, and cost-effectiveness of ECMO in managing severe ARDS. It compared best standard practice vs a protocol that included ECMO. The trial was conducted from 2001 to 2006.
Patients with severe ARDS, as defined by a Murray score29 greater than 3 or uncompensated hypercapnea, were prospectively randomized and recruited from an ECMO center and 148 tertiary intensive care units and referral hospitals in England. This was a pragmatic trial, with minimal exclusion criteria (essentially, mechanical ventilation with high pressures and high FiO2 for more than 7 days, intracranial bleeding, or contraindication to heparinization).
A total of 180 patients were randomized in a one-to-one ratio to receive ECMO or conventional management. The ventilator management in the conventional treatment group was not done according to a protocol but in general was low-volume and low-pressure. All patients randomized to ECMO were transferred to the ECMO center and treated according to a standardized ventilation protocol. After 12 hours, if predefined goals were not reached, venovenous ECMO was started. Patients assigned to conventional management could not cross over to ECMO.
The primary outcomes were death or severe disability at 6 months after randomization, and cost-effectiveness. The secondary outcomes were hospital resource use (eg, rescue techniques, length of stay, duration of ECMO) and health status after 6 months.
Findings. The groups were similar at baseline. Sixty-eight (75%) of the 90 patients randomized to receive ECMO actually received it. Of the 22 patients who did not receive ECMO, 16 (18% of the 90) improved on conventional therapy, 5 (6%) died during or before transfer, and 1 could not receive heparin.
Two patients had severe complications in the ECMO group: one had an arterial puncture, and one had an oxygen delivery failure during transport. In each case, these events contributed to the death of the patient.
More patients in the ECMO group received lung-protective ventilation, 84 (93%) vs 63 (70%).
The primary outcome, ie, death or severe disability at 6 months, occurred in 33 (37%) of the 90 patients in the ECMO group and in 46 (53%) of the patients in the conventional management group (relative risk 0.69, 95% CI 0.05–0.97, P = .03). More patients in the ECMO group survived, but the difference was not statistically significant (relative risk of death 0.73, 95% CI 0.52–1.03, P = .07). The most common cause of death in the ECMO group was multiorgan failure (42%), whereas in the conventional management group, the most common cause of death was respiratory failure (60%).
Length of stay in the hospital and in the critical care unit and health care costs were double for patients in the ECMO group. There was no difference in quality-of-life markers at 6 months in the survivors.
Conclusions. This pragmatic trial demonstrated that a protocol that includes ECMO could improve survival rates in ARDS.
Of note, the ECMO group got care in regional centers that used protocols. Therefore, in interpreting the results of this trial, we have to consider that being in a center with protocol-specified care for ARDS could drive some of the difference in mortality rates.
Regardless, this trial demonstrated that ECMO is feasible and led to better outcomes than expected. The findings were encouraging, and spurred the use of ECMO in severe ARDS during the 2009 H1N1 pandemic. Two propensity-matched studies and a number of case series reported a survival benefit associated with the use of ECMO in patients with severe ARDS.27,30
A recent meta-analysis also reported that ECMO might lower the mortality rate in ARDS; however, the patients in the H1N1 pandemic were younger and usually had isolated respiratory failure.31
The success of ECMO has opened new possibilities in the management of ARDS. As the technology improves and our experience increases, ECMO will likely gain more acceptance as a treatment for severe ARDS.
Airway pressure release ventilation
The use of airway pressure release ventilation and other ventilator modalities in ARDS is not supported by current evidence, though results of clinical trials may influence our practice in the future.
PHARMACOTHERAPY IN ARDS
The pathogenesis of ARDS includes damage to the alveolar-capillary membrane, with leakage of protein-rich edema fluid into alveoli. This damage is propagated by a complex inflammatory response including but not limited to neutrophil activation, free-radical formation, dysregulation of the coagulation system, and extensive release of inflammatory mediators.32,33 As a consequence, there are multiple potential targets for pharmacologic therapy in ARDS.
A variety of drugs, including corticosteroids, anti-inflammatory agents, immune-modulating agents, pulmonary vasodilators, antioxidants, and surfactants, have been studied in patients with ARDS.34 But effective pharmacotherapy for ARDS remains extremely limited.
Neuromuscular blockade in early severe ARDS
Mechanical ventilation can result in injurious stretching of the lung parenchyma, either from alveolar overdistention (volutrauma) or from continual recruitment and derecruitment of unstable lung units during the ventilator cycle (atelectrauma).35 Ventilator-induced lung injury can be exacerbated by asynchronous breathing.
In theory, neuromuscular blockers could minimize patient-ventilator asynchrony and provide much better control of tidal volume and pressure in patients with ARDS. This may result in less volutrauma and atelectrauma associated with asynchronous breathing. Data also suggest that cisatracurium (Nimbex), a neuromuscular blocking agent, may have a direct effect on the amount of inflammation in lungs with ARDS.36
The ACURASYS study
The ARDS et Curarisation Systématique (ACURASYS) study37 was a randomized trial in 340 patients undergoing mechanical ventilation for severe ARDS to evaluate the impact of neuromuscular blockade within the first 48 hours in this population.
The primary outcome was the mortality rate before hospital discharge or within 90 days of study entry. Secondary outcomes included the 28-day mortality rate, the rate of intensive care unit-acquired paresis, and the number of ventilator-free days. To be included, patients had to have been mechanically ventilated for less than 48 hours and to meet the AECC criteria for severe ARDS, with a PaO2/FiO2 ratio less than 150 mm Hg.
The intervention group received a continuous infusion of cisatracurium for 48 hours, while the control patients received placebo. Muscle strength was evaluated by clinical scoring of strength in different muscle groups.
Findings. The study groups were similar at baseline.
The crude 90-day mortality rate was lower in the cisatracurium group (31.6% vs 40.7%, P = .08). Regression analysis showed an improved 90-day survival rate with the use of this neuromuscular blocker after adjustment for severity of illness and the severity of ARDS (based on degree of hypoxemia and plateau pressures) (hazard ratio for death at 90 days 0.68; 95% CI 0.48–0.98; P = .04). The rate of paresis acquired in the intensive care unit did not differ significantly between the two groups.
Conclusion. In patients with severe ARDS, giving a neuromuscular blocking agent early improved the survival rate and increased the time off the ventilator without increasing muscle weakness.
These data are in line with similar findings from two other studies published by the same group.38,39 A meta-analysis of 432 patients showed that the use of neuromuscular blockade in early severe ARDS is associated with a statistically significant effect on early mortality (relative risk 0.66, 95% CI 0.50–0.87).40 The pooled analysis of these trials did not show any statistically significant critical-illness polyneuropathy.
These results need to be interpreted carefully, as we have inadequate data to see if they generalize to different intensive care units, and the evaluation and categorization of critical-illness polyneuropathy remains to be defined.
Cisatracurium is a promising treatment for moderate to severe ARDS and merits investigation in a large confirmatory randomized controlled trial.
Other pharmacologic agents
A number of other drugs have been studied in ARDS patients, including both inhaled and intravenous beta agonists,41,42 statins,43 and nutritional supplements.44 But as with other drugs previously studied in ARDS such as corticosteroids, N-acetylcysteine, and surfactant,34 these agents showed no effect on outcomes. In fact, a recent trial of intravenous salbutamol in ARDS patients was stopped after an interim analysis because of a higher incidence of arrhythmias and lactic acidosis with this agent.42
These findings reaffirm that pharmacologic therapy needs to be carefully considered, and potential harms associated with these therapies need to be addressed before they are introduced in the care of critically ill patients.
Continued progress in understanding the pathophysiology of acute respiratory distress syndrome (ARDS) is translating into changes in the way we diagnose and manage it. Over the past 20 years, low tidal volume,1 positive end-expiratory pressure (PEEP),2 and fluid restriction3 have become the standard of care. A multidisciplinary approach, including targeted use of sedatives, early mobilization, and protocols for weaning from the ventilator, has also brought about substantial changes in ARDS management and its outcomes.4–6
In this article, we review the most relevant articles about ARDS in the last 5 years. We include the new definition of ARDS and studies of ventilatory and nonventilatory therapies that have implications in managing patients with ARDS.
A STANDARDIZED APPROACH
ARDS is characterized by damage to the alveolar architecture, severe hypoxemia, and bilateral parenchymal opacities.
The working definition of ARDS developed in 1994 by the American-European Consensus Conference (AECC) was the basis for enrollment in most of the landmark trials and observational studies over the past 20 years.7,8 However, it was limited in its reliability and validity.
An updated definition
In 2011, the ARDS Definition Task Force, using a novel consensus process, updated the ARDS definition,9 focusing on its feasibility, reliability, and validity in predicting response to therapies and outcomes in ARDS. This new “Berlin” definition is not substantially different from the old, but defines the criteria more specifically:
- Bilateral opacities, unexplained by nodules, atelectasis, or effusion, on chest radiography or computed tomography
- New or worsening respiratory symptoms, or a clinical insult associated with ARDS within 7 days of diagnosis
- Objective assessment of cardiac function (eg, with echocardiography) to exclude cardiogenic pulmonary edema
- Hypoxemia, with a partial pressure of arterial oxygen divided by the percentage of inspired oxygen (PaO2/FiO2 ratio) of 300 mm Hg or less despite noninvasive or invasive mechanical ventilation with PEEP or continuous positive airway pressure (CPAP) of at least 5 cm H2O.
In addition, the new definition classifies the severity of disease on the basis of the degree of hypoxemia, ie, the PaO2/FiO2 ratio:
- Mild: PaO2/FiO2 ratio > 200 and ≤ 300 mm Hg
- Moderate: PaO2/FiO2 ratio > 100 and ≤ 200 mm Hg
- Severe: PaO2/FiO2 ratio ≤ 100 mm Hg.
The term “acute lung injury” has been eliminated, as has the previous criterion of a pulmonary artery wedge pressure of 18 mm Hg or less.
The panel also evaluated four ancillary variables for predicting outcomes in severe ARDS:
- Compliance of the respiratory system less than or equal to 40 mL/cm H2O
- Radiographic severity (involvement of three or four quadrants on chest radiography)
- PEEP of 10 cm H2O or greater
- Corrected expired volume 10 L/min or greater.
The task force evaluated the reliability and validity of this definition in a meta-analysis of 4,400 patients previously enrolled in randomized controlled trials or observational studies.
Findings. The Berlin definition predicted the risk of death better than the AECC definition. The mortality rate increased with the severity of ARDS, from 27% with mild disease to 32% with moderate disease to 45% with severe disease. The four ancillary variables did not contribute to the predictive validity of severe ARDS for mortality and were removed from the definition.
Thille et al10 retrospectively reviewed autopsy findings from 712 patients and found that the new definition identified a homogeneous group who had severe ARDS.10
Conclusions. The new definition may overcome some of the limitations of the old one, but it needs to be validated in clinical practice, especially its ability to predict death.
VENTILATORY SUPPORT
Prompt recognition, lung-protective ventilation, and a conservative fluid strategy remain the cornerstones of ARDS management. However, other strategies are being tested.
Prone-position ventilation in severe ARDS: The right therapy in a specific population
Prone-position ventilation was first described almost 30 years ago, but it has been used inconsistently in clinical practice.
Physiologic and observational studies indicated that prone positioning might improve survival in patients with ARDS, but several randomized trials failed to demonstrate any positive effect on outcomes.11,12 Some trials also reported a higher rate of complications with this intervention.13 However, meta-analyses suggested that prone-position ventilation might have a beneficial effect in patients with severe ARDS (defined as a PaO2/FiO2 ratio ≤ 100 mm Hg).14
In view of these findings, investigators conducted a trial of prone-position ventilation exclusively in patients with severe ARDS.
The PROSEVA study
The Proning Severe ARDS Patients (PROSEVA) study was a randomized controlled trial designed to determine whether prone-position ventilation, applied early, would improve outcomes in patients with severe ARDS.15
In PROSEVA, 466 patients with severe ARDS (defined as a PaO2/FiO2 ratio < 150 mm Hg, FiO2 ≥ 60%, and PEEP ≥ 5 cm H2O) underwent either at least 16 hours of prone positioning or were left in the supine position after 12 to 24 hours of initial conventional mechanical ventilation. The patients were recruited from centers in France and Spain where prone-position ventilation had been used in daily practice for more than 5 years.
The primary outcome studied was the rate of death at 28 days. The secondary end points were the death rate at day 90, rates of successful extubation, the length of stay in the intensive care unit, and complications.
Findings. At study entry, the patients in the supine group were sicker, more of them required a vasopressor, and fewer of them were receiving neuromuscular blocking agents than those in the prone group. These baseline differences may have influenced the outcomes; the unadjusted 28-day mortality rate was 16.0% in the prone group compared with 32.8% in the supine group (P < .001). However, the hazard ratio for death with prone positioning was 0.39 (95% confidence interval [CI] 0.25–0.63) even after adjusting for severity and the use of vasopressors and neuromuscular blocking agents. Prone-position ventilation was not associated with a higher incidence of complications, and the rate of successful extubation was higher.
Conclusions. In patients with severe ARDS, early use of prolonged prone positioning significantly decreased the 28-day and 90-day mortality rates. This trial has made prone positioning one of the strategies in managing patients with early severe ARDS. To minimize complications such as pressure ulcers and line or tube dislodgement, personnel caring for these patients must follow a protocol and undergo specific training.
These results were corroborated by a meta-analysis by Beitler et al16 that found a significant decrease in mortality rate with prone-position ventilation even in older studies when lung-protective ventilation strategies were separated from high-tidal-volume ventilation.
High-frequency oscillatory ventilation: No benefit in two trials
Observational data and experimental studies suggested that high-frequency oscillatory ventilation (HFOV) is superior to conventional mechanical ventilation in ARDS patients.17,18 However, outdated and cumbersome equipment, lack of protocols, and a lack of high-quality evidence led to limited and inconsistent use of HFOV, mainly as a rescue therapy in ARDS.19
Over the last few years, HFOV has been gaining acceptance, especially earlier in the course of ARDS.20 After preliminary clinical trials reported promising results, two trials conducted in Canada and the United Kingdom compared HFOV vs conventional mechanical ventilation in patients with ARDS.
The OSCAR study
The Oscillation in ARDS (OSCAR) study21 was a “pragmatic” trial22 (ie, it had minimal exclusion criteria) of the safety and effectiveness of HFOV as a primary ventilatory strategy for ARDS. It included 795 patients randomized to receive conventional ventilation (n = 397) or HFOV (n = 398). Research centers followed detailed algorithms for HFOV management and adopted their usual practice for conventional ventilation. Medical care was given according to the clinician’s judgment.
The primary outcome studied was survival at 30 days. The secondary outcomes were all-cause mortality in the intensive care unit and the hospital, duration of mechanical ventilation, and use of antimicrobial, sedative, vasoactive, and neuromuscular-blocking drugs.
Findings. The patient baseline characteristics were similar in both groups.
There was no significant difference in intensive care unit mortality rates, hospital mortality rates, or mortality rates at 30 days (41.7% in the HFOV group vs 41.1% in the conventional ventilation group; P = .85, 95% CI 6.1–7.5) even after adjustments for center or severity of illness.
The duration of mechanical ventilation was similar in both groups (14.9 ± 13.3 days in the HFOV group vs 14.1 ± 13.4 days in the conventional ventilation group, P = .41). However, sedatives and neuromuscular-blocking drugs were used more often and longer in the HFOV group than in the conventional ventilation group. There was no difference in the use of vasoactive or antimicrobial medications.
Conclusions. This multicenter randomized control trial did not demonstrate any benefit from using HFOV for routine management of ARDS. Its pragmatic design made it less likely to reach a firm conclusion,22 but it at least made a case against routinely using HFOV in patients with ARDS.
The OSCILLATE study
The Oscillation for Acute Respiratory Distress Syndrome Treated Early (OSCILLATE) study23 assessed the safety and efficacy of HFOV as a treatment for early-onset moderate-to-severe ARDS.
The inclusion criteria were similar to those in the OSCAR trial except that pulmonary symptoms had to be present less than 2 weeks and ARDS assessment was done under standard ventilator settings. As this was an efficacy trial, it had more exclusion criteria than the OSCAR trial. A total of 548 patients were randomized to receive conventional ventilation (n = 273) or HFOV (n = 275). The baseline characteristics were similar between groups.
Conventional ventilation was given according to a protocol used in an earlier trial2 and included recruitment maneuvers. HFOV was given in centers that had experience in this treatment, and there were protocols for ventilation management, hemodynamic optimization, and weaning. All other care was left to the clinician’s choice.
The primary outcome studied was in-hospital mortality. The investigators also evaluated whether there were interactions between the treatment and baseline severity of lung injury and center experience with HFOV.
Findings. The trial was stopped after an interim analysis found that HFOV might be harmful, although the statistical threshold for stopping was not reached. The in-hospital mortality rate was 47% in the HFOV group and 35% in the control group (relative risk of death with HFOV 1.33, 95% CI 1.09–1.64, P = .005). HFOV was worse than conventional ventilation regardless of the severity of disease or center experience. The HFOV group had higher mean airway pressures but similar FiO2 compared with the conventional ventilation group.
The HFOV group received significantly more vasopressors, sedatives, and neuromuscular blockers. This group’s fluid balance was higher as well, but not significantly so. Refractory hypoxemia (defined as PaO2 < 60 mm Hg for 1 hour with an FiO2 of 1.0 and neuromuscular blockade) was more frequent in the conventional ventilation group, but the number of deaths in the subgroup with refractory hypoxemia was similar with either treatment.
Conclusions. This multicenter randomized controlled trial demonstrated that HFOV was harmful when used routinely to manage ARDS. The trial’s protocol was based on the results of a pilot study carried out by the same investigators, which provided the best evidence available regarding the safety of HFOV at that time.
The results of the OSCAR and OSCILLATE trials have quelled enthusiasm for early, routine use of HFOV in ARDS. Although there are concerns that the protocol (ie, the way HFOV was implemented) rather than HFOV itself may have led to worse outcomes, there is no signal to support its routine use. We need further studies to define if it remains a viable rescue therapy.
Extracorporeal membrane oxygenation: Is it a viable option in severe ARDS?
Extracorporeal membrane oxygenation (ECMO) uses cardiopulmonary bypass technology to provide gas exchange. In patients with severe hypoxemia, ECMO can ensure adequate oxygenation and ventilation while ensuring the optimization of lung-protective ventilation. But ECMO was never as successful in adults with ARDS as it was in children and neonates.24
The first two trials of ECMO in ARDS24,25 reported equal or worse survival rates compared with conventional ventilation, and the overall mortality rate in these studies was staggeringly high. However, these studies were carried out before the era of lung-protective ventilation and at a time when ECMO technology was relatively primitive.
With new technology such as venovenous circuits and smaller cannulas, ECMO has gained more acceptance. It was used in patients with severe or refractory hypoxemia associated with ARDS during the H1N1 pandemic.26,27
The CESAR trial
The Conventional Ventilatory Support Versus Extracorporeal Membrane Oxygenation for Severe Adult Respiratory Failure (CESAR) trial28 assessed the safety, clinical efficacy, and cost-effectiveness of ECMO in managing severe ARDS. It compared best standard practice vs a protocol that included ECMO. The trial was conducted from 2001 to 2006.
Patients with severe ARDS, as defined by a Murray score29 greater than 3 or uncompensated hypercapnea, were prospectively randomized and recruited from an ECMO center and 148 tertiary intensive care units and referral hospitals in England. This was a pragmatic trial, with minimal exclusion criteria (essentially, mechanical ventilation with high pressures and high FiO2 for more than 7 days, intracranial bleeding, or contraindication to heparinization).
A total of 180 patients were randomized in a one-to-one ratio to receive ECMO or conventional management. The ventilator management in the conventional treatment group was not done according to a protocol but in general was low-volume and low-pressure. All patients randomized to ECMO were transferred to the ECMO center and treated according to a standardized ventilation protocol. After 12 hours, if predefined goals were not reached, venovenous ECMO was started. Patients assigned to conventional management could not cross over to ECMO.
The primary outcomes were death or severe disability at 6 months after randomization, and cost-effectiveness. The secondary outcomes were hospital resource use (eg, rescue techniques, length of stay, duration of ECMO) and health status after 6 months.
Findings. The groups were similar at baseline. Sixty-eight (75%) of the 90 patients randomized to receive ECMO actually received it. Of the 22 patients who did not receive ECMO, 16 (18% of the 90) improved on conventional therapy, 5 (6%) died during or before transfer, and 1 could not receive heparin.
Two patients had severe complications in the ECMO group: one had an arterial puncture, and one had an oxygen delivery failure during transport. In each case, these events contributed to the death of the patient.
More patients in the ECMO group received lung-protective ventilation, 84 (93%) vs 63 (70%).
The primary outcome, ie, death or severe disability at 6 months, occurred in 33 (37%) of the 90 patients in the ECMO group and in 46 (53%) of the patients in the conventional management group (relative risk 0.69, 95% CI 0.05–0.97, P = .03). More patients in the ECMO group survived, but the difference was not statistically significant (relative risk of death 0.73, 95% CI 0.52–1.03, P = .07). The most common cause of death in the ECMO group was multiorgan failure (42%), whereas in the conventional management group, the most common cause of death was respiratory failure (60%).
Length of stay in the hospital and in the critical care unit and health care costs were double for patients in the ECMO group. There was no difference in quality-of-life markers at 6 months in the survivors.
Conclusions. This pragmatic trial demonstrated that a protocol that includes ECMO could improve survival rates in ARDS.
Of note, the ECMO group got care in regional centers that used protocols. Therefore, in interpreting the results of this trial, we have to consider that being in a center with protocol-specified care for ARDS could drive some of the difference in mortality rates.
Regardless, this trial demonstrated that ECMO is feasible and led to better outcomes than expected. The findings were encouraging, and spurred the use of ECMO in severe ARDS during the 2009 H1N1 pandemic. Two propensity-matched studies and a number of case series reported a survival benefit associated with the use of ECMO in patients with severe ARDS.27,30
A recent meta-analysis also reported that ECMO might lower the mortality rate in ARDS; however, the patients in the H1N1 pandemic were younger and usually had isolated respiratory failure.31
The success of ECMO has opened new possibilities in the management of ARDS. As the technology improves and our experience increases, ECMO will likely gain more acceptance as a treatment for severe ARDS.
Airway pressure release ventilation
The use of airway pressure release ventilation and other ventilator modalities in ARDS is not supported by current evidence, though results of clinical trials may influence our practice in the future.
PHARMACOTHERAPY IN ARDS
The pathogenesis of ARDS includes damage to the alveolar-capillary membrane, with leakage of protein-rich edema fluid into alveoli. This damage is propagated by a complex inflammatory response including but not limited to neutrophil activation, free-radical formation, dysregulation of the coagulation system, and extensive release of inflammatory mediators.32,33 As a consequence, there are multiple potential targets for pharmacologic therapy in ARDS.
A variety of drugs, including corticosteroids, anti-inflammatory agents, immune-modulating agents, pulmonary vasodilators, antioxidants, and surfactants, have been studied in patients with ARDS.34 But effective pharmacotherapy for ARDS remains extremely limited.
Neuromuscular blockade in early severe ARDS
Mechanical ventilation can result in injurious stretching of the lung parenchyma, either from alveolar overdistention (volutrauma) or from continual recruitment and derecruitment of unstable lung units during the ventilator cycle (atelectrauma).35 Ventilator-induced lung injury can be exacerbated by asynchronous breathing.
In theory, neuromuscular blockers could minimize patient-ventilator asynchrony and provide much better control of tidal volume and pressure in patients with ARDS. This may result in less volutrauma and atelectrauma associated with asynchronous breathing. Data also suggest that cisatracurium (Nimbex), a neuromuscular blocking agent, may have a direct effect on the amount of inflammation in lungs with ARDS.36
The ACURASYS study
The ARDS et Curarisation Systématique (ACURASYS) study37 was a randomized trial in 340 patients undergoing mechanical ventilation for severe ARDS to evaluate the impact of neuromuscular blockade within the first 48 hours in this population.
The primary outcome was the mortality rate before hospital discharge or within 90 days of study entry. Secondary outcomes included the 28-day mortality rate, the rate of intensive care unit-acquired paresis, and the number of ventilator-free days. To be included, patients had to have been mechanically ventilated for less than 48 hours and to meet the AECC criteria for severe ARDS, with a PaO2/FiO2 ratio less than 150 mm Hg.
The intervention group received a continuous infusion of cisatracurium for 48 hours, while the control patients received placebo. Muscle strength was evaluated by clinical scoring of strength in different muscle groups.
Findings. The study groups were similar at baseline.
The crude 90-day mortality rate was lower in the cisatracurium group (31.6% vs 40.7%, P = .08). Regression analysis showed an improved 90-day survival rate with the use of this neuromuscular blocker after adjustment for severity of illness and the severity of ARDS (based on degree of hypoxemia and plateau pressures) (hazard ratio for death at 90 days 0.68; 95% CI 0.48–0.98; P = .04). The rate of paresis acquired in the intensive care unit did not differ significantly between the two groups.
Conclusion. In patients with severe ARDS, giving a neuromuscular blocking agent early improved the survival rate and increased the time off the ventilator without increasing muscle weakness.
These data are in line with similar findings from two other studies published by the same group.38,39 A meta-analysis of 432 patients showed that the use of neuromuscular blockade in early severe ARDS is associated with a statistically significant effect on early mortality (relative risk 0.66, 95% CI 0.50–0.87).40 The pooled analysis of these trials did not show any statistically significant critical-illness polyneuropathy.
These results need to be interpreted carefully, as we have inadequate data to see if they generalize to different intensive care units, and the evaluation and categorization of critical-illness polyneuropathy remains to be defined.
Cisatracurium is a promising treatment for moderate to severe ARDS and merits investigation in a large confirmatory randomized controlled trial.
Other pharmacologic agents
A number of other drugs have been studied in ARDS patients, including both inhaled and intravenous beta agonists,41,42 statins,43 and nutritional supplements.44 But as with other drugs previously studied in ARDS such as corticosteroids, N-acetylcysteine, and surfactant,34 these agents showed no effect on outcomes. In fact, a recent trial of intravenous salbutamol in ARDS patients was stopped after an interim analysis because of a higher incidence of arrhythmias and lactic acidosis with this agent.42
These findings reaffirm that pharmacologic therapy needs to be carefully considered, and potential harms associated with these therapies need to be addressed before they are introduced in the care of critically ill patients.
- Ventilation with lower tidal volumes as compared with traditional tidal volumes for acute lung injury and the acute respiratory distress syndrome. Acute Respiratory Distress Syndrome Network. N Engl J Med 2000; 342:1301–1308.
- Meade MO, Cook DJ, Guyatt GH, et al; Lung Open Ventilation Study Investigators. Ventilation strategy using low tidal volumes, recruitment maneuvers, and high positive end-expiratory pressure for acute lung injury and acute respiratory distress syndrome: a randomized controlled trial. JAMA 2008; 299:637–645.
- National Heart, Lung, and Blood Institute Acute Respiratory Distress Syndrome (ARDS) Clinical Trials Network; Wiedemann HP, Wheeler AP, Bernard GR, et al. Comparison of two fluid-management strategies in acute lung injury. N Engl J Med 2006; 354:2564–2575.
- Girard TD, Kress JP, Fuchs BD, et al. Efficacy and safety of a paired sedation and ventilator weaning protocol for mechanically ventilated patients in intensive care (Awakening and Breathing Controlled trial): a randomised controlled trial. Lancet 2008; 371:126–134.
- Schweickert WD, Pohlman MC, Pohlman AS, et al. Early physical and occupational therapy in mechanically ventilated, critically ill patients: a randomised controlled trial. Lancet 2009; 373:1874–1882.
- Ely EW, Baker AM, Dunagan DP, et al. Effect on the duration of mechanical ventilation of identifying patients capable of breathing spontaneously. N Engl J Med 1996; 335:1864–1869.
- Bernard GR, Artigas A, Brigham KL, et al. The American-European Consensus Conference on ARDS. Definitions, mechanisms, relevant outcomes, and clinical trial coordination. Am J Respir Crit Care Med 1994; 149:818–824.
- Ferguson ND, Fan E, Camporota L, et al. The Berlin definition of ARDS: an expanded rationale, justification, and supplementary material. Intensive Care Med 2012; 38:1573–1582.
- ARDS Definition Task Force; Ranieri VM, Rubenfeld GD, Thompson BT, et al. Acute respiratory distress syndrome: the Berlin definition. JAMA 2012; 307:2526–2533.
- Thille AW, Esteban A, Fernández-Segoviano P, et al. Comparison of the Berlin definition for acute respiratory distress syndrome with autopsy. Am J Respir Crit Care Med 2013; 187:761–767.
- Gattinoni L, Tognoni G, Pesenti A, et al; Prone-Supine Study Group. Effect of prone positioning on the survival of patients with acute respiratory failure. N Engl J Med 2001; 345:568–573.
- Taccone P, Pesenti A, Latini R, et al; Prone-Supine II Study Group. Prone positioning in patients with moderate and severe acute respiratory distress syndrome: a randomized controlled trial. JAMA 2009; 302:1977–1984.
- Mancebo J, Fernández R, Blanch L, et al. A multicenter trial of prolonged prone ventilation in severe acute respiratory distress syndrome. Am J Respir Crit Care Med 2006; 173:1233–1239.
- Sud S, Friedrich JO, Taccone P, et al. Prone ventilation reduces mortality in patients with acute respiratory failure and severe hypoxemia: systematic review and meta-analysis. Intensive Care Med 2010; 36:585–599.
- Guérin C, Reignier J, Richard JC, et al; PROSEVA Study Group. Prone positioning in severe acute respiratory distress syndrome. N Engl J Med 2013; 368:2159–2168.
- Beitler JR, Shaefi S, Montesi SB, et al. Prone positioning reduces mortality from acute respiratory distress syndrome in the low tidal volume era: a meta-analysis. Intensive Care Med 2014; 40:332–341.
- Chan KP, Stewart TE, Mehta S. High-frequency oscillatory ventilation for adult patients with ARDS. Chest 2007; 131:1907–1916.
- Fessler HE, Hager DN, Brower RG. Feasibility of very high-frequency ventilation in adults with acute respiratory distress syndrome. Crit Care Med 2008; 36:1043–1048.
- Mehta S, Granton J, MacDonald RJ, et al. High-frequency oscillatory ventilation in adults: the Toronto experience. Chest 2004; 126:518–527.
- Ferguson ND, Chiche JD, Kacmarek RM, et al. Combining high-frequency oscillatory ventilation and recruitment maneuvers in adults with early acute respiratory distress syndrome: the Treatment with Oscillation and an Open Lung Strategy (TOOLS) Trial pilot study. Crit Care Med 2005; 33:479–486.
- Young D, Lamb SE, Shah S, et al; OSCAR Study Group. High-frequency oscillation for acute respiratory distress syndrome. N Engl J Med 2013; 368:806–813.
- Thorpe KE, Zwarenstein M, Oxman AD, et al. A pragmatic-explanatory continuum indicator summary (PRECIS): a tool to help trial designers. J Clin Epidemiol 2009; 62:464–475.
- Ferguson ND, Cook DJ, Guyatt GH, et al; OSCILLATE Trial Investigators; Canadian Critical Care Trials Group. High-frequency oscillation in early acute respiratory distress syndrome. N Engl J Med 2013; 368:795–805.
- Morris AH, Wallace CJ, Menlove RL, et al. Randomized clinical trial of pressure-controlled inverse ratio ventilation and extracorporeal CO2 removal for adult respiratory distress syndrome. Am J Respir Crit Care Med 1994; 149:295–305.
- Zapol WM, Snider MT, Hill JD, et al. Extracorporeal membrane oxygenation in severe acute respiratory failure. A randomized prospective study. JAMA 1979; 242:2193–2196.
- Australia and New Zealand Extracorporeal Membrane Oxygenation (ANZ ECMO) Influenza Investigators; Davies A, Jones D, Bailey M, et al. Extracorporeal Membrane Oxygenation for 2009 Influenza A(H1N1) Acute Respiratory Distress Syndrome. JAMA 2009; 302:1888–1895.
- Pham T, Combes A, Rozé H, et al; REVA Research Network. Extracorporeal membrane oxygenation for pandemic influenza A(H1N1)-induced acute respiratory distress syndrome: a cohort study and propensity-matched analysis. Am J Respir Crit Care Med 2013; 187:276–285.
- Peek GJ, Mugford M, Tiruvoipati R, et al; CESAR trial collaboration. Efficacy and economic assessment of conventional ventilatory support versus extracorporeal membrane oxygenation for severe adult respiratory failure (CESAR): a multicentre randomised controlled trial. Lancet 2009; 374:1351–1363.
- Murray JF, Matthay MA, Luce JM, Flick MR. An expanded definition of the adult respiratory distress syndrome. Am Rev Respir Dis 1988; 138:720–723.
- Noah MA, Peek GJ, Finney SJ, et al. Referral to an extracorporeal membrane oxygenation center and mortality among patients with severe 2009 influenza A(H1N1). JAMA 2011; 306:1659–1668.
- Zampieri FG, Mendes PV, Ranzani OT, et al. Extracorporeal membrane oxygenation for severe respiratory failure in adult patients: a systematic review and meta-analysis of current evidence. J Crit Care 2013; 28:998–1005.
- Raghavendran K, Pryhuber GS, Chess PR, Davidson BA, Knight PR, Notter RH. Pharmacotherapy of acute lung injury and acute respiratory distress syndrome. Curr Med Chem 2008; 15:1911–1924.
- Adhikari N, Burns KE, Meade MO. Pharmacologic treatments for acute respiratory distress syndrome and acute lung injury: systematic review and meta-analysis. Treat Respir Med 2004; 3:307–328.
- Adhikari N, Burns KE, Meade MO. Pharmacologic therapies for adults with acute lung injury and acute respiratory distress syndrome. Cochrane Database Syst Rev 2004; 4:CD004477.
- Terragni PP, Rosboch GL, Lisi A, Viale AG, Ranieri VM. How respiratory system mechanics may help in minimising ventilator-induced lung injury in ARDS patients. Eur Respir J Suppl 2003; 42:15s–21s.
- Forel JM, Roch A, Papazian L. Paralytics in critical care: not always the bad guy. Curr Opin Crit Care 2009; 15:59–66.
- Papazian L, Forel JM, Gacouin A, et al; ACURASYS Study Investigators. Neuromuscular blockers in early acute respiratory distress syndrome. N Engl J Med 2010; 363:1107–1116.
- Gainnier M, Roch A, Forel JM, et al. Effect of neuromuscular blocking agents on gas exchange in patients presenting with acute respiratory distress syndrome. Crit Care Med 2004; 32:113–19.
- Forel JM, Roch A, Marin V, et al. Neuromuscular blocking agents decrease inflammatory response in patients presenting with acute respiratory distress syndrome. Crit Care Med 2006; 34:2749–2757.
- Alhazzani W, Alshahrani M, Jaeschke R, et al. Neuromuscular blocking agents in acute respiratory distress syndrome: a systematic review and meta-analysis of randomized controlled trials. Crit Care 2013; 17:R43.
- National Heart, Lung, and Blood Institute Acute Respiratory Distress Syndrome (ARDS) Clinical Trials Network; Matthay MA, Brower RG, Carson S, et al. Randomized, placebo-controlled clinical trial of an aerosolized beta-2-agonist for treatment of acute lung injury. Am J Respir Crit Care Med 2011; 184:561–568.
- Gao Smith F, Perkins GD, Gates S, et al; BALTI-2 study investigators. Effect of intravenous beta-2 agonist treatment on clinical outcomes in acute respiratory distress syndrome (BALTI-2): a multicentre, randomised controlled trial. Lancet 2012; 379:229–235.
- Craig TR, Duffy MJ, Shyamsundar M, et al. A randomized clinical trial of hydroxymethylglutaryl-coenzyme a reductase inhibition for acute lung injury (The HARP Study). Am J Respir Crit Care Med 2011; 183:620–626.
- National Heart, Lung, and Blood Institute Acute Respiratory Distress Syndrome (ARDS) Clinical Trials Network; Rice TW, Wheeler AP, Thompson BT, et al. Initial trophic vs full enteral feeding in patients with acute lung injury: the EDEN randomized trial. JAMA 2012; 307:795–803.
- Ventilation with lower tidal volumes as compared with traditional tidal volumes for acute lung injury and the acute respiratory distress syndrome. Acute Respiratory Distress Syndrome Network. N Engl J Med 2000; 342:1301–1308.
- Meade MO, Cook DJ, Guyatt GH, et al; Lung Open Ventilation Study Investigators. Ventilation strategy using low tidal volumes, recruitment maneuvers, and high positive end-expiratory pressure for acute lung injury and acute respiratory distress syndrome: a randomized controlled trial. JAMA 2008; 299:637–645.
- National Heart, Lung, and Blood Institute Acute Respiratory Distress Syndrome (ARDS) Clinical Trials Network; Wiedemann HP, Wheeler AP, Bernard GR, et al. Comparison of two fluid-management strategies in acute lung injury. N Engl J Med 2006; 354:2564–2575.
- Girard TD, Kress JP, Fuchs BD, et al. Efficacy and safety of a paired sedation and ventilator weaning protocol for mechanically ventilated patients in intensive care (Awakening and Breathing Controlled trial): a randomised controlled trial. Lancet 2008; 371:126–134.
- Schweickert WD, Pohlman MC, Pohlman AS, et al. Early physical and occupational therapy in mechanically ventilated, critically ill patients: a randomised controlled trial. Lancet 2009; 373:1874–1882.
- Ely EW, Baker AM, Dunagan DP, et al. Effect on the duration of mechanical ventilation of identifying patients capable of breathing spontaneously. N Engl J Med 1996; 335:1864–1869.
- Bernard GR, Artigas A, Brigham KL, et al. The American-European Consensus Conference on ARDS. Definitions, mechanisms, relevant outcomes, and clinical trial coordination. Am J Respir Crit Care Med 1994; 149:818–824.
- Ferguson ND, Fan E, Camporota L, et al. The Berlin definition of ARDS: an expanded rationale, justification, and supplementary material. Intensive Care Med 2012; 38:1573–1582.
- ARDS Definition Task Force; Ranieri VM, Rubenfeld GD, Thompson BT, et al. Acute respiratory distress syndrome: the Berlin definition. JAMA 2012; 307:2526–2533.
- Thille AW, Esteban A, Fernández-Segoviano P, et al. Comparison of the Berlin definition for acute respiratory distress syndrome with autopsy. Am J Respir Crit Care Med 2013; 187:761–767.
- Gattinoni L, Tognoni G, Pesenti A, et al; Prone-Supine Study Group. Effect of prone positioning on the survival of patients with acute respiratory failure. N Engl J Med 2001; 345:568–573.
- Taccone P, Pesenti A, Latini R, et al; Prone-Supine II Study Group. Prone positioning in patients with moderate and severe acute respiratory distress syndrome: a randomized controlled trial. JAMA 2009; 302:1977–1984.
- Mancebo J, Fernández R, Blanch L, et al. A multicenter trial of prolonged prone ventilation in severe acute respiratory distress syndrome. Am J Respir Crit Care Med 2006; 173:1233–1239.
- Sud S, Friedrich JO, Taccone P, et al. Prone ventilation reduces mortality in patients with acute respiratory failure and severe hypoxemia: systematic review and meta-analysis. Intensive Care Med 2010; 36:585–599.
- Guérin C, Reignier J, Richard JC, et al; PROSEVA Study Group. Prone positioning in severe acute respiratory distress syndrome. N Engl J Med 2013; 368:2159–2168.
- Beitler JR, Shaefi S, Montesi SB, et al. Prone positioning reduces mortality from acute respiratory distress syndrome in the low tidal volume era: a meta-analysis. Intensive Care Med 2014; 40:332–341.
- Chan KP, Stewart TE, Mehta S. High-frequency oscillatory ventilation for adult patients with ARDS. Chest 2007; 131:1907–1916.
- Fessler HE, Hager DN, Brower RG. Feasibility of very high-frequency ventilation in adults with acute respiratory distress syndrome. Crit Care Med 2008; 36:1043–1048.
- Mehta S, Granton J, MacDonald RJ, et al. High-frequency oscillatory ventilation in adults: the Toronto experience. Chest 2004; 126:518–527.
- Ferguson ND, Chiche JD, Kacmarek RM, et al. Combining high-frequency oscillatory ventilation and recruitment maneuvers in adults with early acute respiratory distress syndrome: the Treatment with Oscillation and an Open Lung Strategy (TOOLS) Trial pilot study. Crit Care Med 2005; 33:479–486.
- Young D, Lamb SE, Shah S, et al; OSCAR Study Group. High-frequency oscillation for acute respiratory distress syndrome. N Engl J Med 2013; 368:806–813.
- Thorpe KE, Zwarenstein M, Oxman AD, et al. A pragmatic-explanatory continuum indicator summary (PRECIS): a tool to help trial designers. J Clin Epidemiol 2009; 62:464–475.
- Ferguson ND, Cook DJ, Guyatt GH, et al; OSCILLATE Trial Investigators; Canadian Critical Care Trials Group. High-frequency oscillation in early acute respiratory distress syndrome. N Engl J Med 2013; 368:795–805.
- Morris AH, Wallace CJ, Menlove RL, et al. Randomized clinical trial of pressure-controlled inverse ratio ventilation and extracorporeal CO2 removal for adult respiratory distress syndrome. Am J Respir Crit Care Med 1994; 149:295–305.
- Zapol WM, Snider MT, Hill JD, et al. Extracorporeal membrane oxygenation in severe acute respiratory failure. A randomized prospective study. JAMA 1979; 242:2193–2196.
- Australia and New Zealand Extracorporeal Membrane Oxygenation (ANZ ECMO) Influenza Investigators; Davies A, Jones D, Bailey M, et al. Extracorporeal Membrane Oxygenation for 2009 Influenza A(H1N1) Acute Respiratory Distress Syndrome. JAMA 2009; 302:1888–1895.
- Pham T, Combes A, Rozé H, et al; REVA Research Network. Extracorporeal membrane oxygenation for pandemic influenza A(H1N1)-induced acute respiratory distress syndrome: a cohort study and propensity-matched analysis. Am J Respir Crit Care Med 2013; 187:276–285.
- Peek GJ, Mugford M, Tiruvoipati R, et al; CESAR trial collaboration. Efficacy and economic assessment of conventional ventilatory support versus extracorporeal membrane oxygenation for severe adult respiratory failure (CESAR): a multicentre randomised controlled trial. Lancet 2009; 374:1351–1363.
- Murray JF, Matthay MA, Luce JM, Flick MR. An expanded definition of the adult respiratory distress syndrome. Am Rev Respir Dis 1988; 138:720–723.
- Noah MA, Peek GJ, Finney SJ, et al. Referral to an extracorporeal membrane oxygenation center and mortality among patients with severe 2009 influenza A(H1N1). JAMA 2011; 306:1659–1668.
- Zampieri FG, Mendes PV, Ranzani OT, et al. Extracorporeal membrane oxygenation for severe respiratory failure in adult patients: a systematic review and meta-analysis of current evidence. J Crit Care 2013; 28:998–1005.
- Raghavendran K, Pryhuber GS, Chess PR, Davidson BA, Knight PR, Notter RH. Pharmacotherapy of acute lung injury and acute respiratory distress syndrome. Curr Med Chem 2008; 15:1911–1924.
- Adhikari N, Burns KE, Meade MO. Pharmacologic treatments for acute respiratory distress syndrome and acute lung injury: systematic review and meta-analysis. Treat Respir Med 2004; 3:307–328.
- Adhikari N, Burns KE, Meade MO. Pharmacologic therapies for adults with acute lung injury and acute respiratory distress syndrome. Cochrane Database Syst Rev 2004; 4:CD004477.
- Terragni PP, Rosboch GL, Lisi A, Viale AG, Ranieri VM. How respiratory system mechanics may help in minimising ventilator-induced lung injury in ARDS patients. Eur Respir J Suppl 2003; 42:15s–21s.
- Forel JM, Roch A, Papazian L. Paralytics in critical care: not always the bad guy. Curr Opin Crit Care 2009; 15:59–66.
- Papazian L, Forel JM, Gacouin A, et al; ACURASYS Study Investigators. Neuromuscular blockers in early acute respiratory distress syndrome. N Engl J Med 2010; 363:1107–1116.
- Gainnier M, Roch A, Forel JM, et al. Effect of neuromuscular blocking agents on gas exchange in patients presenting with acute respiratory distress syndrome. Crit Care Med 2004; 32:113–19.
- Forel JM, Roch A, Marin V, et al. Neuromuscular blocking agents decrease inflammatory response in patients presenting with acute respiratory distress syndrome. Crit Care Med 2006; 34:2749–2757.
- Alhazzani W, Alshahrani M, Jaeschke R, et al. Neuromuscular blocking agents in acute respiratory distress syndrome: a systematic review and meta-analysis of randomized controlled trials. Crit Care 2013; 17:R43.
- National Heart, Lung, and Blood Institute Acute Respiratory Distress Syndrome (ARDS) Clinical Trials Network; Matthay MA, Brower RG, Carson S, et al. Randomized, placebo-controlled clinical trial of an aerosolized beta-2-agonist for treatment of acute lung injury. Am J Respir Crit Care Med 2011; 184:561–568.
- Gao Smith F, Perkins GD, Gates S, et al; BALTI-2 study investigators. Effect of intravenous beta-2 agonist treatment on clinical outcomes in acute respiratory distress syndrome (BALTI-2): a multicentre, randomised controlled trial. Lancet 2012; 379:229–235.
- Craig TR, Duffy MJ, Shyamsundar M, et al. A randomized clinical trial of hydroxymethylglutaryl-coenzyme a reductase inhibition for acute lung injury (The HARP Study). Am J Respir Crit Care Med 2011; 183:620–626.
- National Heart, Lung, and Blood Institute Acute Respiratory Distress Syndrome (ARDS) Clinical Trials Network; Rice TW, Wheeler AP, Thompson BT, et al. Initial trophic vs full enteral feeding in patients with acute lung injury: the EDEN randomized trial. JAMA 2012; 307:795–803.
KEY POINTS
- The new definition of ARDS categorizes it as mild, moderate, or severe on the basis of oxygenation, specifically, the PaO2/FiO2 ratio.
- Neuromuscular blockade and prone positioning, used early in moderate or severe cases of ARDS, have shown some promise in trials, but questions remain about their application in critically ill patients.
- Based on two large trials, HFOV is no longer recommended as a primary therapy for ARDS, but it may still be considered as a rescue therapy in patients with refractory hypoxemia.
- In light of observational studies and randomized trials, ECMO should be considered an option in cases of refractory hypoxemia.
A 61-year-old man with fluctuating hypertension
A 61-year-old man with type 2 diabetes mellitus on glimepiride therapy presented with somnolence and slurred speech. His capillary glucose level was 17 mg/dL and his serum glucose level was 28 mg/dL. He was treated with intravenous dextrose, and his glucose level promptly returned to normal.
He had been adherent to his medication regimen and denied overmedicating or accidental overdosing. Over the past 7 months, he had noted redness on his palms, a rash on his legs, intermittent moderate to severe headaches, weight loss, and decreased appetite. In addition, his blood pressure had been labile, which his physicians had attributed to autonomic instability. He had continued on the same dose of glimepiride despite losing weight.
His history included multivessel coronary artery disease treated with angioplasty and placement of multiple coronary stents; ischemic cardiomyopathy with a left ventricular ejection fraction of 28%; implantation of a cardioverter-defibrillator for secondary prevention of ventricular arrhythmia; an ischemic stroke; and multiple sclerosis complicated by bilateral blindness, with optic nerve involvement and autonomic instability, present for over a year and manifested by labile blood pressure. He was a long-time tobacco user. His daily medications included ticagrelor 90 mg, aspirin 81 mg, metoprolol 50 mg, ramipril 10 mg, simvastatin 20 mg, glimepiride 2 mg, and esomeprazole 40 mg. He needed help taking his medications.
At the time of hospital admission, his heart rate was 69 beats per minute with a regular rhythm, blood pressure 115/73 mm Hg, respiratory rate 11 breaths per minute with an oxygen saturation of 99% on room air, and oral temperature 34.7°C (94.5°F). He appeared to be in no distress.
Cardiovascular examination revealed no murmurs or gallops; there was mild nonpitting edema of the lower extremities. Pulmonary, abdominal, and neurologic examinations were unrevealing except for bilateral blindness. Vascular examination revealed no bruits. Results of a complete blood cell count and metabolic panel were normal except for a hemoglobin level of 9.9 g/dL (reference range 13.5–17.5) and a platelet count of 477 × 109/L (150–450).
Although he continued to receive the same medications he had been taking at home, his blood pressure fluctuated. On the second hospital day, it reached 186/135 mm Hg, at which time he also had palpitations, dyspnea, and crackles in the lower lobes of both lungs. Volume resuscitation on admission was suspected to have played a role, and he received furosemide, which improved his symptoms. But several hours later, his blood pressure rose again, and he became diaphoretic. Despite aggressive treatment with different antihypertensive agents, his blood pressure remained high and his symptoms persisted. Chest radiography showed no evidence of pulmonary edema. Because of his progressive dyspnea, the diagnosis of pulmonary embolism was entertained.
CAUSES OF RESISTANT HYPERTENSION
1. What could explain this patient’s high blood pressure?
- A drug effect
- Renovascular disease
- Excess circulating catecholamines
- Obstructive sleep apnea
- Primary aldosteronism
Sympathomimetic drugs such as epinephrine, norepinephrine, dopamine, and vasopressin, which are used when hemodynamic support is required, can raise both systolic and diastolic blood pressure. Nonsteroidal anti-inflammatory drugs and nasal decongestants are common culprits in the community. However, our patient was using none of these drugs.
Renovascular disease is one of many causes of resistant hypertension, accounting for 8% of all cases.1,2 Despite fluctuations, the blood pressure often remains chronically elevated, its changes are less paroxysmal than in our patient, and a precipitating factor such as a dietary indiscretion is sometimes identified.1
Excess circulating catecholamines can be a result of stress, exogenous administration, or endogenous oversecretion. Our patient’s clinical presentation is highly suspicious for a high-catecholamine state, and this should be further evaluated.
Obstructive sleep apnea is common in patients with resistant hypertension, with an estimated prevalence as high as 60% in this group.3,4
Primary aldosteronism has an estimated prevalence of about 20% in patients evaluated for resistant hypertension.5
AN ADRENAL MASS IS INCIDENTALLY DISCOVERED
Computed tomographic angiography of the chest revealed no evidence of pulmonary emboli. There was mild dilation of the central pulmonary arteries and an incidental, incompletely imaged 4.7-by-3.4-cm mass of mixed attenuation in the right adrenal gland, with macroscopic fat within the lesion.
Computed tomography (CT) of the abdomen with dedicated cuts through the adrenal glands revealed a 4.7-cm heterogeneous right adrenal mass with a density of 34 Hounsfield units (HU). The left adrenal gland appeared diffusely enlarged without a discretely seen mass, consistent with hyperplasticity (Figure 1).
2. Based on the patient’s clinical presentation and findings on CT, what would be the most likely diagnosis for this incidentally found adrenal mass?
- Adrenocortical adenoma
- Adrenocortical carcinoma
- Metastatic mass
- Pheochromocytoma
Adrenocortical adenoma can present as a small homogeneous mass of variable size, with smooth margins, and rarely containing hemorrhagic tissue or calcifications. The typical density on nonenhanced CT is less than 10 HU. On enhanced CT, it is nonvascular. T2-weighted magnetic resonance imaging (MRI) shows a lesion of the same intensity as liver tissue.6
Adrenocortical adenoma is not classically associated with autologous activity and thus is less likely to explain our patient’s symptoms.
Adrenocortical carcinoma can present as a large heterogeneous mass, usually greater than 4 cm in diameter, with irregular margins and areas of necrosis, hemorrhage, or calcification. The typical density on nonenhanced CT is greater than 10 HU. On enhanced CT, the mass is usually vascular, and T2-weighted MRI will show a lesion more intense than liver tissue.6
Adrenocortical carcinoma is also not classically associated with autologous activity, and so is not likely to explain our patient’s symptoms.6
Metastatic disease can present with masses of variable size, often bilaterally, and occasionally with cysts or areas of hemorrhage. The typical density of metastatic lesions on nonenhanced CT is greater than 10 HU. On enhanced CT, they are usually vascular, and on T2-weighted MRI they are hyperintense.6 The characteristics of the mass and the absence of a primary malignancy on CT of the chest and abdomen do not support the diagnosis of metastatic disease.
Pheochromocytoma is a neuroendocrine tumor of the adrenal medulla that can present as a large heterogeneous mass, greater than 3 cm in diameter, with clear margins and cysts or areas of hemorrhage. Extra-adrenal neuroendocrine tumors are typically called paragangliomas and have features similar to those of pheochromocytoma. The typical density of pheochromocytoma on nonenhanced CT is greater than 10 HU. On enhanced CT, it is usually vascular, and T2-weighted MRI shows a hyperintense lesion. Pheochromocytoma can be biochemically active and thus can cause signs and symptoms that will lead to the diagnosis.6
Other imaging tests may play a role in the evaluation of adrenal masses but are not required for the diagnosis of pheochromocytoma. Functional positron emission tomography using metaiodobenzylguanidine labeled with iodine 123 or-iodine 131 or using the glucose analogue F-18 fluorodeoxyglucose has been used in the initial assessment of pheochromocytoma, with good sensitivity and specificity.7,8
Our patient’s pacemaker-defibrillator precluded him from undergoing MRI.
DIAGNOSIS: PHEOCHROMOCYTOMA
Pheochromocytoma was highly suspected on the basis of the patient’s clinical presentation, and metoprolol was immediately discontinued. He was started on the calcium channel blocker verapamil and the alpha-blocker phenoxybenzamine.
Serum samples were obtained to measure metanephrines, dehydroepiandrosterone, aldosterone, and cortisol, and a 24-hour urine collection was obtained to measure creatinine, dopamine, epinephrine, norepinephrine, cortisol, and metanephrines. Based on the results (Table 1) and on the findings on imaging, the patient was diagnosed with pheochromocytoma. A surgical consultation was obtained, and surgery was recommended.
WHEN DOES PHEOCHROMOCYTOMA CALL FOR SURGERY?
3. Which criterion is most important when determining the need for surgery for pheochromocytoma?
- Findings on fine-needle aspiration biopsy
- Biochemical activity
- Size of the mass
- Bilateral masses
Fine-needle aspiration biopsy can be done when a mass is found incidentally and no evidence of biochemical activity is detected, although it is not an essential part of the diagnostic workup.9 In most cases, the sampling from fine-needle aspiration is not sufficient to achieve a diagnosis.
Biochemical activity is the most important factor when determining the need for prompt surgical intervention. The excess circulating catecholamines have been associated with increased risk of cardiovascular morbidity and death independent of the morbidity associated with hypertension alone.10 Biochemical activity can be independent of the size of the mass, but larger masses typically present with symptoms.
Bilateral masses have been associated with metastatic disease.11 In retrospect, the patient’s history of hypertension and cerebrovascular accident could be associated with the development of a catecholamine-releasing tumor.
A GOOD OUTCOME FROM SURGERY
The patient was continued on phenoxybenzamine for 7 days and responded well to this therapy.
After this preoperative preparation, he underwent laparoscopic right adrenalectomy with excision of a retroperitoneal adrenal mass. His postoperative course was complicated by transient hypotension requiring low-dose vasopressin support for less than 24 hours. He was then restarted on his previous dosage of metoprolol and was discharged home on postoperative day 5 with stable blood pressure. Follow-up 24-hour urine collection 1 month after he was discharged showed normalization of metanephrine, normetanephrine, epinephrine, and norepinephrine levels.
Despite low suspicion for an underlying genetic syndrome, he was referred for genetic testing and was scheduled to have a repeat 24-hour urine collection and imaging in 6 months to follow his enlarged left adrenal gland, which did not appear to be metabolically hyperactive.
4. What is the most common perioperative complication of pheochromocytoma excision?
- Hypoglycemia
- Hypotension
- Hypocortisolism
- Hypertension
- Tachycardia
Hypoglycemia has been observed after removal of pheochromocytoma, as levels of catecholamines (which normally inhibit pancreatic beta cells) decrease and insulin secretion consequently increases.12 Our patient developed hypoglycemia before surgery, not after, and it was likely due to the combination of his antidiabetic therapy, weight loss, and decreased oral intake.
Hypotension is the most common complication in the perioperative period. It is associated with excessive loss of catecholamine secretion. It is usually short-lived but may require aggressive administration of intravenous fluids and use of sympathomimetic agents.
Hypocortisolism is unlikely in patients with pheochromocytoma, but it is likely after removal of adrenocortical adenoma.
Hypertension and tachycardia affect up to 40% of pheochromocytoma patients in some case series.12
PHEOCHROMOCYTOMA: A CATECHOLAMINE-SECRETING TUMOR
The pathophysiology of pheochromocytoma is complex. It is characterized by accelerated growth of cells producing catecholamines, which may produce symptoms when secreted into the bloodstream. The classic triad of symptoms is headache, hypertension, and hyperglycemia, although our patient had very low blood sugar levels. Other common symptoms are nausea, orthostasis, and tremor, although not all symptoms are invariably seen.
Genetic testing recommended
Genetic associations have been described and are thought to be responsible for 20% to 30% of cases of pheochromocytoma. All associated germline mutations are autosomal dominant, some with variable penetrance. These include:
- Succinate dehydrogenase subunit B, C, and D mutations
- von Hippel-Lindau syndrome
- Multiple endocrine neoplasia type 1 and type 2 syndromes
- Neurofibromatosis type 1.13,14
The succinate dehydrogenase subunit mutations have been associated with, but not limited to, extra-adrenal adenomas (paragangliomas) and carry a worse prognosis.
Some experts recommend genetic testing in all cases of pheochromocytoma, sporadic or familial, and this testing should be followed by counseling if a mutation is found.15 Others recommend genetic testing based on the patient’s age (under age 50), history, imaging, and biochemical features of the tumor (metanephrines predominate in multiple endocrine neoplasia syndromes, and normetanephrines in von Hippel-Lindau syndrome).13
Serious consequences
A thorough evaluation is recommended, since pheochromocytoma has been associated with increased cardiovascular morbidity. In a retrospective series, Stolk et al10 reported that patients with pheochromocytoma had a higher incidence of myocardial infarction, angina, and stroke in the years preceding the diagnosis than did patients with essential hypertension (13.8% vs 1.1%, P < .001).10
Catecholamine cardiomyopathy has been described and shares clinical features with Takotsubo or stress cardiomyopathy, with global left ventricular systolic and diastolic dysfunction that improve or resolve after the adrenergic insult is removed.16
Conditions that warrant further evaluation or that may suggest pheochromocytoma are malignant hypertension, hypertensive encephalopathy, ischemic stroke, subarachnoid hemorrhage, acute pulmonary edema, angina pectoris, myocardial infarction, aortic dissection, and kidney injury.
When to suspect pheochromocytoma
Pheochromocytoma should be suspected in a patient with resistant hypertension, family history, or imaging findings that suggest an adrenal mass with a heterogeneous appearance. The diagnostic algorithm follows the same pathway as for the evaluation of an incidentally found adrenal mass, with determination of its dimension and characteristics by CT or MRI, and with biochemical testing of urine catecholamines, plasma free metanephrines, renin, aldosterone, and cortisol.
The diagnosis of pheochromocytoma is established by obtaining fractionated metanephrines and catecholamines in a 24-hour urine collection (sensitivity 90%, specificity 98%). Analysis of plasma metanephrines has a higher sensitivity (97%) but lower specificity (85%).17 The combination of typical signs, symptoms, and laboratory findings makes the diagnosis likely, especially in combination with a unilateral adrenal mass.
Laparoscopic surgery after medical preparation for active tumors
If the mass appears benign and not biochemically hyperactive, then follow-up at 1 year is recommended, with repeat testing. Surgical evaluation and intervention is recommended for lesions that appear malignant or that are biochemically active and clinically symptomatic.9
Preoperative hemodynamic control is essential in the management of pheochromocytoma to prevent or minimize hemodynamic changes that can be driven by increased catecholamines. Control is typically achieved with initial alpha-blockade and then beta-blockade to avoid worsening hypertension and to prevent an acute hypertensive crisis during surgical intervention. Phenoxybenzamine, the mainstay of therapy, is a nonselective alpha-blocker with a long duration of action that requires titration over several days up to 3 weeks.
A selective alpha-1-blocker such as doxazosin can be used to control postoperative hypotension, as it has a shorter half-life than phenoxybenzamine. Alternative strategies include calcium channel blockers, centrally acting sympathetic blockers, and magnesium.18
Laparoscopic adrenalectomy by an experienced surgeon after excellent medical preparation is often considered the treatment of choice, but for larger or malignant masses, an open procedure is recommended. The risk of perioperative morbidity and death can be reduced by adequate medical management. With successful surgical resection, the long-term prognosis is favorable.
- Calhoun DA, Jones D, Textor S, et al. Resistant hypertension: diagnosis, evaluation, and treatment. A scientific statement from the American Heart Association Professional Education Committee of the Council for High Blood Pressure Research. Hypertension 2008; 51:1403–1419.
- Kumar N, Calhoun DA, Dudenbostel T. Management of patients with resistant hypertension: current treatment options. Integr Blood Press Control 2013; 6:139–151.
- Pedrosa RP, Drager LF, Gonzaga CC, et al. Obstructive sleep apnea: the most common secondary cause of hypertension associated with resistant hypertension. Hypertension 2011; 58:811–817.
- Marcus JA, Pothineni A, Marcus CZ, Bisognano JD. The role of obesity and obstructive sleep apnea in the pathogenesis and treatment of resistant hypertension. Curr Hypertens Rep 2014; 16:411.
- Calhoun DA, Nishizaka MK, Zaman MA, Thakkar RB, Weissmann P. Hyperaldosteronism among black and white subjects with resistant hypertension. Hypertension 2002; 40:892–896.
- Young WF Clinical practice. The incidentally discovered adrenal mass. N Engl J Med 2007; 356:601–610.
- Lin M, Wong V, Yap J, Jin R, Leong P, Campbell P. FDG PET in the evaluation of phaeochromocytoma: a correlative study with MIBG scintigraphy and Ki-67 proliferative index. Clin Imaging 2013; 37:1084–1088.
- Raja A, Leung K, Stamm M, Girgis S, Low G. Multimodality imaging findings of pheochromocytoma with associated clinical and biochemical features in 53 patients with histologically confirmed tumors. AJR Am J Roentgenol 2013; 201:825–833.
- Nieman LK. Approach to the patient with an adrenal incidentaloma. J Clin Endocrinol Metab 2010; 95:4106–4113.
- Stolk RF, Bakx C, Mulder J, Timmers HJ, Lenders JW. Is the excess cardiovascular morbidity in pheochromocytoma related to blood pressure or to catecholamines? J Clin Endocrinol Metab 2013; 98:1100–1106.
- Grumbach MM, Biller BM, Braunstein GD, et al. Management of the clinically inapparent adrenal mass (‘incidentaloma’). Ann Intern Med 2003; 138:424–429.
- Lentschener C, Gaujoux S, Tesniere A, Dousset B. Point of controversy: perioperative care of patients undergoing pheochromocytoma removal—time for a reappraisal? Eur J Endocrinol 2011; 165:365–373.
- Bryant J, Farmer J, Kessler LJ, Townsend RR, Nathanson KL. Pheochromocytoma: the expanding genetic differential diagnosis. J Natl Cancer Inst 2003; 95:1196–1204.
- Lee P, Leonard J. Textbook on endocrinology. BMJ 1994; 308:1512.
- Fishbein L, Merrill S, Fraker DL, Cohen DL, Nathanson KL. Inherited mutations in pheochromocytoma and paraganglioma: why all patients should be offered genetic testing. Ann Surg Oncol 2013; 20:1444–1450.
- Agarwal G, Sadacharan D, Kapoor A, et al. Cardiovascular dysfunction and catecholamine cardiomyopathy in pheochromocytoma patients and their reversal following surgical cure: results of a prospective case-control study. Surgery 2011; 150:1202–1211.
- Sawka AM, Jaeschke R, Singh RJ, Young WF A comparison of biochemical tests for pheochromocytoma: measurement of fractionated plasma metanephrines compared with the combination of 24-hour urinary metanephrines and catecholamines. J Clin Endocrinol Metab 2003; 88:553–558.
- Domi R, Laho H. Management of pheochromocytoma: old ideas and new drugs. Niger J Clin Pract 2012; 15:253–257.
A 61-year-old man with type 2 diabetes mellitus on glimepiride therapy presented with somnolence and slurred speech. His capillary glucose level was 17 mg/dL and his serum glucose level was 28 mg/dL. He was treated with intravenous dextrose, and his glucose level promptly returned to normal.
He had been adherent to his medication regimen and denied overmedicating or accidental overdosing. Over the past 7 months, he had noted redness on his palms, a rash on his legs, intermittent moderate to severe headaches, weight loss, and decreased appetite. In addition, his blood pressure had been labile, which his physicians had attributed to autonomic instability. He had continued on the same dose of glimepiride despite losing weight.
His history included multivessel coronary artery disease treated with angioplasty and placement of multiple coronary stents; ischemic cardiomyopathy with a left ventricular ejection fraction of 28%; implantation of a cardioverter-defibrillator for secondary prevention of ventricular arrhythmia; an ischemic stroke; and multiple sclerosis complicated by bilateral blindness, with optic nerve involvement and autonomic instability, present for over a year and manifested by labile blood pressure. He was a long-time tobacco user. His daily medications included ticagrelor 90 mg, aspirin 81 mg, metoprolol 50 mg, ramipril 10 mg, simvastatin 20 mg, glimepiride 2 mg, and esomeprazole 40 mg. He needed help taking his medications.
At the time of hospital admission, his heart rate was 69 beats per minute with a regular rhythm, blood pressure 115/73 mm Hg, respiratory rate 11 breaths per minute with an oxygen saturation of 99% on room air, and oral temperature 34.7°C (94.5°F). He appeared to be in no distress.
Cardiovascular examination revealed no murmurs or gallops; there was mild nonpitting edema of the lower extremities. Pulmonary, abdominal, and neurologic examinations were unrevealing except for bilateral blindness. Vascular examination revealed no bruits. Results of a complete blood cell count and metabolic panel were normal except for a hemoglobin level of 9.9 g/dL (reference range 13.5–17.5) and a platelet count of 477 × 109/L (150–450).
Although he continued to receive the same medications he had been taking at home, his blood pressure fluctuated. On the second hospital day, it reached 186/135 mm Hg, at which time he also had palpitations, dyspnea, and crackles in the lower lobes of both lungs. Volume resuscitation on admission was suspected to have played a role, and he received furosemide, which improved his symptoms. But several hours later, his blood pressure rose again, and he became diaphoretic. Despite aggressive treatment with different antihypertensive agents, his blood pressure remained high and his symptoms persisted. Chest radiography showed no evidence of pulmonary edema. Because of his progressive dyspnea, the diagnosis of pulmonary embolism was entertained.
CAUSES OF RESISTANT HYPERTENSION
1. What could explain this patient’s high blood pressure?
- A drug effect
- Renovascular disease
- Excess circulating catecholamines
- Obstructive sleep apnea
- Primary aldosteronism
Sympathomimetic drugs such as epinephrine, norepinephrine, dopamine, and vasopressin, which are used when hemodynamic support is required, can raise both systolic and diastolic blood pressure. Nonsteroidal anti-inflammatory drugs and nasal decongestants are common culprits in the community. However, our patient was using none of these drugs.
Renovascular disease is one of many causes of resistant hypertension, accounting for 8% of all cases.1,2 Despite fluctuations, the blood pressure often remains chronically elevated, its changes are less paroxysmal than in our patient, and a precipitating factor such as a dietary indiscretion is sometimes identified.1
Excess circulating catecholamines can be a result of stress, exogenous administration, or endogenous oversecretion. Our patient’s clinical presentation is highly suspicious for a high-catecholamine state, and this should be further evaluated.
Obstructive sleep apnea is common in patients with resistant hypertension, with an estimated prevalence as high as 60% in this group.3,4
Primary aldosteronism has an estimated prevalence of about 20% in patients evaluated for resistant hypertension.5
AN ADRENAL MASS IS INCIDENTALLY DISCOVERED
Computed tomographic angiography of the chest revealed no evidence of pulmonary emboli. There was mild dilation of the central pulmonary arteries and an incidental, incompletely imaged 4.7-by-3.4-cm mass of mixed attenuation in the right adrenal gland, with macroscopic fat within the lesion.
Computed tomography (CT) of the abdomen with dedicated cuts through the adrenal glands revealed a 4.7-cm heterogeneous right adrenal mass with a density of 34 Hounsfield units (HU). The left adrenal gland appeared diffusely enlarged without a discretely seen mass, consistent with hyperplasticity (Figure 1).
2. Based on the patient’s clinical presentation and findings on CT, what would be the most likely diagnosis for this incidentally found adrenal mass?
- Adrenocortical adenoma
- Adrenocortical carcinoma
- Metastatic mass
- Pheochromocytoma
Adrenocortical adenoma can present as a small homogeneous mass of variable size, with smooth margins, and rarely containing hemorrhagic tissue or calcifications. The typical density on nonenhanced CT is less than 10 HU. On enhanced CT, it is nonvascular. T2-weighted magnetic resonance imaging (MRI) shows a lesion of the same intensity as liver tissue.6
Adrenocortical adenoma is not classically associated with autologous activity and thus is less likely to explain our patient’s symptoms.
Adrenocortical carcinoma can present as a large heterogeneous mass, usually greater than 4 cm in diameter, with irregular margins and areas of necrosis, hemorrhage, or calcification. The typical density on nonenhanced CT is greater than 10 HU. On enhanced CT, the mass is usually vascular, and T2-weighted MRI will show a lesion more intense than liver tissue.6
Adrenocortical carcinoma is also not classically associated with autologous activity, and so is not likely to explain our patient’s symptoms.6
Metastatic disease can present with masses of variable size, often bilaterally, and occasionally with cysts or areas of hemorrhage. The typical density of metastatic lesions on nonenhanced CT is greater than 10 HU. On enhanced CT, they are usually vascular, and on T2-weighted MRI they are hyperintense.6 The characteristics of the mass and the absence of a primary malignancy on CT of the chest and abdomen do not support the diagnosis of metastatic disease.
Pheochromocytoma is a neuroendocrine tumor of the adrenal medulla that can present as a large heterogeneous mass, greater than 3 cm in diameter, with clear margins and cysts or areas of hemorrhage. Extra-adrenal neuroendocrine tumors are typically called paragangliomas and have features similar to those of pheochromocytoma. The typical density of pheochromocytoma on nonenhanced CT is greater than 10 HU. On enhanced CT, it is usually vascular, and T2-weighted MRI shows a hyperintense lesion. Pheochromocytoma can be biochemically active and thus can cause signs and symptoms that will lead to the diagnosis.6
Other imaging tests may play a role in the evaluation of adrenal masses but are not required for the diagnosis of pheochromocytoma. Functional positron emission tomography using metaiodobenzylguanidine labeled with iodine 123 or-iodine 131 or using the glucose analogue F-18 fluorodeoxyglucose has been used in the initial assessment of pheochromocytoma, with good sensitivity and specificity.7,8
Our patient’s pacemaker-defibrillator precluded him from undergoing MRI.
DIAGNOSIS: PHEOCHROMOCYTOMA
Pheochromocytoma was highly suspected on the basis of the patient’s clinical presentation, and metoprolol was immediately discontinued. He was started on the calcium channel blocker verapamil and the alpha-blocker phenoxybenzamine.
Serum samples were obtained to measure metanephrines, dehydroepiandrosterone, aldosterone, and cortisol, and a 24-hour urine collection was obtained to measure creatinine, dopamine, epinephrine, norepinephrine, cortisol, and metanephrines. Based on the results (Table 1) and on the findings on imaging, the patient was diagnosed with pheochromocytoma. A surgical consultation was obtained, and surgery was recommended.
WHEN DOES PHEOCHROMOCYTOMA CALL FOR SURGERY?
3. Which criterion is most important when determining the need for surgery for pheochromocytoma?
- Findings on fine-needle aspiration biopsy
- Biochemical activity
- Size of the mass
- Bilateral masses
Fine-needle aspiration biopsy can be done when a mass is found incidentally and no evidence of biochemical activity is detected, although it is not an essential part of the diagnostic workup.9 In most cases, the sampling from fine-needle aspiration is not sufficient to achieve a diagnosis.
Biochemical activity is the most important factor when determining the need for prompt surgical intervention. The excess circulating catecholamines have been associated with increased risk of cardiovascular morbidity and death independent of the morbidity associated with hypertension alone.10 Biochemical activity can be independent of the size of the mass, but larger masses typically present with symptoms.
Bilateral masses have been associated with metastatic disease.11 In retrospect, the patient’s history of hypertension and cerebrovascular accident could be associated with the development of a catecholamine-releasing tumor.
A GOOD OUTCOME FROM SURGERY
The patient was continued on phenoxybenzamine for 7 days and responded well to this therapy.
After this preoperative preparation, he underwent laparoscopic right adrenalectomy with excision of a retroperitoneal adrenal mass. His postoperative course was complicated by transient hypotension requiring low-dose vasopressin support for less than 24 hours. He was then restarted on his previous dosage of metoprolol and was discharged home on postoperative day 5 with stable blood pressure. Follow-up 24-hour urine collection 1 month after he was discharged showed normalization of metanephrine, normetanephrine, epinephrine, and norepinephrine levels.
Despite low suspicion for an underlying genetic syndrome, he was referred for genetic testing and was scheduled to have a repeat 24-hour urine collection and imaging in 6 months to follow his enlarged left adrenal gland, which did not appear to be metabolically hyperactive.
4. What is the most common perioperative complication of pheochromocytoma excision?
- Hypoglycemia
- Hypotension
- Hypocortisolism
- Hypertension
- Tachycardia
Hypoglycemia has been observed after removal of pheochromocytoma, as levels of catecholamines (which normally inhibit pancreatic beta cells) decrease and insulin secretion consequently increases.12 Our patient developed hypoglycemia before surgery, not after, and it was likely due to the combination of his antidiabetic therapy, weight loss, and decreased oral intake.
Hypotension is the most common complication in the perioperative period. It is associated with excessive loss of catecholamine secretion. It is usually short-lived but may require aggressive administration of intravenous fluids and use of sympathomimetic agents.
Hypocortisolism is unlikely in patients with pheochromocytoma, but it is likely after removal of adrenocortical adenoma.
Hypertension and tachycardia affect up to 40% of pheochromocytoma patients in some case series.12
PHEOCHROMOCYTOMA: A CATECHOLAMINE-SECRETING TUMOR
The pathophysiology of pheochromocytoma is complex. It is characterized by accelerated growth of cells producing catecholamines, which may produce symptoms when secreted into the bloodstream. The classic triad of symptoms is headache, hypertension, and hyperglycemia, although our patient had very low blood sugar levels. Other common symptoms are nausea, orthostasis, and tremor, although not all symptoms are invariably seen.
Genetic testing recommended
Genetic associations have been described and are thought to be responsible for 20% to 30% of cases of pheochromocytoma. All associated germline mutations are autosomal dominant, some with variable penetrance. These include:
- Succinate dehydrogenase subunit B, C, and D mutations
- von Hippel-Lindau syndrome
- Multiple endocrine neoplasia type 1 and type 2 syndromes
- Neurofibromatosis type 1.13,14
The succinate dehydrogenase subunit mutations have been associated with, but not limited to, extra-adrenal adenomas (paragangliomas) and carry a worse prognosis.
Some experts recommend genetic testing in all cases of pheochromocytoma, sporadic or familial, and this testing should be followed by counseling if a mutation is found.15 Others recommend genetic testing based on the patient’s age (under age 50), history, imaging, and biochemical features of the tumor (metanephrines predominate in multiple endocrine neoplasia syndromes, and normetanephrines in von Hippel-Lindau syndrome).13
Serious consequences
A thorough evaluation is recommended, since pheochromocytoma has been associated with increased cardiovascular morbidity. In a retrospective series, Stolk et al10 reported that patients with pheochromocytoma had a higher incidence of myocardial infarction, angina, and stroke in the years preceding the diagnosis than did patients with essential hypertension (13.8% vs 1.1%, P < .001).10
Catecholamine cardiomyopathy has been described and shares clinical features with Takotsubo or stress cardiomyopathy, with global left ventricular systolic and diastolic dysfunction that improve or resolve after the adrenergic insult is removed.16
Conditions that warrant further evaluation or that may suggest pheochromocytoma are malignant hypertension, hypertensive encephalopathy, ischemic stroke, subarachnoid hemorrhage, acute pulmonary edema, angina pectoris, myocardial infarction, aortic dissection, and kidney injury.
When to suspect pheochromocytoma
Pheochromocytoma should be suspected in a patient with resistant hypertension, family history, or imaging findings that suggest an adrenal mass with a heterogeneous appearance. The diagnostic algorithm follows the same pathway as for the evaluation of an incidentally found adrenal mass, with determination of its dimension and characteristics by CT or MRI, and with biochemical testing of urine catecholamines, plasma free metanephrines, renin, aldosterone, and cortisol.
The diagnosis of pheochromocytoma is established by obtaining fractionated metanephrines and catecholamines in a 24-hour urine collection (sensitivity 90%, specificity 98%). Analysis of plasma metanephrines has a higher sensitivity (97%) but lower specificity (85%).17 The combination of typical signs, symptoms, and laboratory findings makes the diagnosis likely, especially in combination with a unilateral adrenal mass.
Laparoscopic surgery after medical preparation for active tumors
If the mass appears benign and not biochemically hyperactive, then follow-up at 1 year is recommended, with repeat testing. Surgical evaluation and intervention is recommended for lesions that appear malignant or that are biochemically active and clinically symptomatic.9
Preoperative hemodynamic control is essential in the management of pheochromocytoma to prevent or minimize hemodynamic changes that can be driven by increased catecholamines. Control is typically achieved with initial alpha-blockade and then beta-blockade to avoid worsening hypertension and to prevent an acute hypertensive crisis during surgical intervention. Phenoxybenzamine, the mainstay of therapy, is a nonselective alpha-blocker with a long duration of action that requires titration over several days up to 3 weeks.
A selective alpha-1-blocker such as doxazosin can be used to control postoperative hypotension, as it has a shorter half-life than phenoxybenzamine. Alternative strategies include calcium channel blockers, centrally acting sympathetic blockers, and magnesium.18
Laparoscopic adrenalectomy by an experienced surgeon after excellent medical preparation is often considered the treatment of choice, but for larger or malignant masses, an open procedure is recommended. The risk of perioperative morbidity and death can be reduced by adequate medical management. With successful surgical resection, the long-term prognosis is favorable.
A 61-year-old man with type 2 diabetes mellitus on glimepiride therapy presented with somnolence and slurred speech. His capillary glucose level was 17 mg/dL and his serum glucose level was 28 mg/dL. He was treated with intravenous dextrose, and his glucose level promptly returned to normal.
He had been adherent to his medication regimen and denied overmedicating or accidental overdosing. Over the past 7 months, he had noted redness on his palms, a rash on his legs, intermittent moderate to severe headaches, weight loss, and decreased appetite. In addition, his blood pressure had been labile, which his physicians had attributed to autonomic instability. He had continued on the same dose of glimepiride despite losing weight.
His history included multivessel coronary artery disease treated with angioplasty and placement of multiple coronary stents; ischemic cardiomyopathy with a left ventricular ejection fraction of 28%; implantation of a cardioverter-defibrillator for secondary prevention of ventricular arrhythmia; an ischemic stroke; and multiple sclerosis complicated by bilateral blindness, with optic nerve involvement and autonomic instability, present for over a year and manifested by labile blood pressure. He was a long-time tobacco user. His daily medications included ticagrelor 90 mg, aspirin 81 mg, metoprolol 50 mg, ramipril 10 mg, simvastatin 20 mg, glimepiride 2 mg, and esomeprazole 40 mg. He needed help taking his medications.
At the time of hospital admission, his heart rate was 69 beats per minute with a regular rhythm, blood pressure 115/73 mm Hg, respiratory rate 11 breaths per minute with an oxygen saturation of 99% on room air, and oral temperature 34.7°C (94.5°F). He appeared to be in no distress.
Cardiovascular examination revealed no murmurs or gallops; there was mild nonpitting edema of the lower extremities. Pulmonary, abdominal, and neurologic examinations were unrevealing except for bilateral blindness. Vascular examination revealed no bruits. Results of a complete blood cell count and metabolic panel were normal except for a hemoglobin level of 9.9 g/dL (reference range 13.5–17.5) and a platelet count of 477 × 109/L (150–450).
Although he continued to receive the same medications he had been taking at home, his blood pressure fluctuated. On the second hospital day, it reached 186/135 mm Hg, at which time he also had palpitations, dyspnea, and crackles in the lower lobes of both lungs. Volume resuscitation on admission was suspected to have played a role, and he received furosemide, which improved his symptoms. But several hours later, his blood pressure rose again, and he became diaphoretic. Despite aggressive treatment with different antihypertensive agents, his blood pressure remained high and his symptoms persisted. Chest radiography showed no evidence of pulmonary edema. Because of his progressive dyspnea, the diagnosis of pulmonary embolism was entertained.
CAUSES OF RESISTANT HYPERTENSION
1. What could explain this patient’s high blood pressure?
- A drug effect
- Renovascular disease
- Excess circulating catecholamines
- Obstructive sleep apnea
- Primary aldosteronism
Sympathomimetic drugs such as epinephrine, norepinephrine, dopamine, and vasopressin, which are used when hemodynamic support is required, can raise both systolic and diastolic blood pressure. Nonsteroidal anti-inflammatory drugs and nasal decongestants are common culprits in the community. However, our patient was using none of these drugs.
Renovascular disease is one of many causes of resistant hypertension, accounting for 8% of all cases.1,2 Despite fluctuations, the blood pressure often remains chronically elevated, its changes are less paroxysmal than in our patient, and a precipitating factor such as a dietary indiscretion is sometimes identified.1
Excess circulating catecholamines can be a result of stress, exogenous administration, or endogenous oversecretion. Our patient’s clinical presentation is highly suspicious for a high-catecholamine state, and this should be further evaluated.
Obstructive sleep apnea is common in patients with resistant hypertension, with an estimated prevalence as high as 60% in this group.3,4
Primary aldosteronism has an estimated prevalence of about 20% in patients evaluated for resistant hypertension.5
AN ADRENAL MASS IS INCIDENTALLY DISCOVERED
Computed tomographic angiography of the chest revealed no evidence of pulmonary emboli. There was mild dilation of the central pulmonary arteries and an incidental, incompletely imaged 4.7-by-3.4-cm mass of mixed attenuation in the right adrenal gland, with macroscopic fat within the lesion.
Computed tomography (CT) of the abdomen with dedicated cuts through the adrenal glands revealed a 4.7-cm heterogeneous right adrenal mass with a density of 34 Hounsfield units (HU). The left adrenal gland appeared diffusely enlarged without a discretely seen mass, consistent with hyperplasticity (Figure 1).
2. Based on the patient’s clinical presentation and findings on CT, what would be the most likely diagnosis for this incidentally found adrenal mass?
- Adrenocortical adenoma
- Adrenocortical carcinoma
- Metastatic mass
- Pheochromocytoma
Adrenocortical adenoma can present as a small homogeneous mass of variable size, with smooth margins, and rarely containing hemorrhagic tissue or calcifications. The typical density on nonenhanced CT is less than 10 HU. On enhanced CT, it is nonvascular. T2-weighted magnetic resonance imaging (MRI) shows a lesion of the same intensity as liver tissue.6
Adrenocortical adenoma is not classically associated with autologous activity and thus is less likely to explain our patient’s symptoms.
Adrenocortical carcinoma can present as a large heterogeneous mass, usually greater than 4 cm in diameter, with irregular margins and areas of necrosis, hemorrhage, or calcification. The typical density on nonenhanced CT is greater than 10 HU. On enhanced CT, the mass is usually vascular, and T2-weighted MRI will show a lesion more intense than liver tissue.6
Adrenocortical carcinoma is also not classically associated with autologous activity, and so is not likely to explain our patient’s symptoms.6
Metastatic disease can present with masses of variable size, often bilaterally, and occasionally with cysts or areas of hemorrhage. The typical density of metastatic lesions on nonenhanced CT is greater than 10 HU. On enhanced CT, they are usually vascular, and on T2-weighted MRI they are hyperintense.6 The characteristics of the mass and the absence of a primary malignancy on CT of the chest and abdomen do not support the diagnosis of metastatic disease.
Pheochromocytoma is a neuroendocrine tumor of the adrenal medulla that can present as a large heterogeneous mass, greater than 3 cm in diameter, with clear margins and cysts or areas of hemorrhage. Extra-adrenal neuroendocrine tumors are typically called paragangliomas and have features similar to those of pheochromocytoma. The typical density of pheochromocytoma on nonenhanced CT is greater than 10 HU. On enhanced CT, it is usually vascular, and T2-weighted MRI shows a hyperintense lesion. Pheochromocytoma can be biochemically active and thus can cause signs and symptoms that will lead to the diagnosis.6
Other imaging tests may play a role in the evaluation of adrenal masses but are not required for the diagnosis of pheochromocytoma. Functional positron emission tomography using metaiodobenzylguanidine labeled with iodine 123 or-iodine 131 or using the glucose analogue F-18 fluorodeoxyglucose has been used in the initial assessment of pheochromocytoma, with good sensitivity and specificity.7,8
Our patient’s pacemaker-defibrillator precluded him from undergoing MRI.
DIAGNOSIS: PHEOCHROMOCYTOMA
Pheochromocytoma was highly suspected on the basis of the patient’s clinical presentation, and metoprolol was immediately discontinued. He was started on the calcium channel blocker verapamil and the alpha-blocker phenoxybenzamine.
Serum samples were obtained to measure metanephrines, dehydroepiandrosterone, aldosterone, and cortisol, and a 24-hour urine collection was obtained to measure creatinine, dopamine, epinephrine, norepinephrine, cortisol, and metanephrines. Based on the results (Table 1) and on the findings on imaging, the patient was diagnosed with pheochromocytoma. A surgical consultation was obtained, and surgery was recommended.
WHEN DOES PHEOCHROMOCYTOMA CALL FOR SURGERY?
3. Which criterion is most important when determining the need for surgery for pheochromocytoma?
- Findings on fine-needle aspiration biopsy
- Biochemical activity
- Size of the mass
- Bilateral masses
Fine-needle aspiration biopsy can be done when a mass is found incidentally and no evidence of biochemical activity is detected, although it is not an essential part of the diagnostic workup.9 In most cases, the sampling from fine-needle aspiration is not sufficient to achieve a diagnosis.
Biochemical activity is the most important factor when determining the need for prompt surgical intervention. The excess circulating catecholamines have been associated with increased risk of cardiovascular morbidity and death independent of the morbidity associated with hypertension alone.10 Biochemical activity can be independent of the size of the mass, but larger masses typically present with symptoms.
Bilateral masses have been associated with metastatic disease.11 In retrospect, the patient’s history of hypertension and cerebrovascular accident could be associated with the development of a catecholamine-releasing tumor.
A GOOD OUTCOME FROM SURGERY
The patient was continued on phenoxybenzamine for 7 days and responded well to this therapy.
After this preoperative preparation, he underwent laparoscopic right adrenalectomy with excision of a retroperitoneal adrenal mass. His postoperative course was complicated by transient hypotension requiring low-dose vasopressin support for less than 24 hours. He was then restarted on his previous dosage of metoprolol and was discharged home on postoperative day 5 with stable blood pressure. Follow-up 24-hour urine collection 1 month after he was discharged showed normalization of metanephrine, normetanephrine, epinephrine, and norepinephrine levels.
Despite low suspicion for an underlying genetic syndrome, he was referred for genetic testing and was scheduled to have a repeat 24-hour urine collection and imaging in 6 months to follow his enlarged left adrenal gland, which did not appear to be metabolically hyperactive.
4. What is the most common perioperative complication of pheochromocytoma excision?
- Hypoglycemia
- Hypotension
- Hypocortisolism
- Hypertension
- Tachycardia
Hypoglycemia has been observed after removal of pheochromocytoma, as levels of catecholamines (which normally inhibit pancreatic beta cells) decrease and insulin secretion consequently increases.12 Our patient developed hypoglycemia before surgery, not after, and it was likely due to the combination of his antidiabetic therapy, weight loss, and decreased oral intake.
Hypotension is the most common complication in the perioperative period. It is associated with excessive loss of catecholamine secretion. It is usually short-lived but may require aggressive administration of intravenous fluids and use of sympathomimetic agents.
Hypocortisolism is unlikely in patients with pheochromocytoma, but it is likely after removal of adrenocortical adenoma.
Hypertension and tachycardia affect up to 40% of pheochromocytoma patients in some case series.12
PHEOCHROMOCYTOMA: A CATECHOLAMINE-SECRETING TUMOR
The pathophysiology of pheochromocytoma is complex. It is characterized by accelerated growth of cells producing catecholamines, which may produce symptoms when secreted into the bloodstream. The classic triad of symptoms is headache, hypertension, and hyperglycemia, although our patient had very low blood sugar levels. Other common symptoms are nausea, orthostasis, and tremor, although not all symptoms are invariably seen.
Genetic testing recommended
Genetic associations have been described and are thought to be responsible for 20% to 30% of cases of pheochromocytoma. All associated germline mutations are autosomal dominant, some with variable penetrance. These include:
- Succinate dehydrogenase subunit B, C, and D mutations
- von Hippel-Lindau syndrome
- Multiple endocrine neoplasia type 1 and type 2 syndromes
- Neurofibromatosis type 1.13,14
The succinate dehydrogenase subunit mutations have been associated with, but not limited to, extra-adrenal adenomas (paragangliomas) and carry a worse prognosis.
Some experts recommend genetic testing in all cases of pheochromocytoma, sporadic or familial, and this testing should be followed by counseling if a mutation is found.15 Others recommend genetic testing based on the patient’s age (under age 50), history, imaging, and biochemical features of the tumor (metanephrines predominate in multiple endocrine neoplasia syndromes, and normetanephrines in von Hippel-Lindau syndrome).13
Serious consequences
A thorough evaluation is recommended, since pheochromocytoma has been associated with increased cardiovascular morbidity. In a retrospective series, Stolk et al10 reported that patients with pheochromocytoma had a higher incidence of myocardial infarction, angina, and stroke in the years preceding the diagnosis than did patients with essential hypertension (13.8% vs 1.1%, P < .001).10
Catecholamine cardiomyopathy has been described and shares clinical features with Takotsubo or stress cardiomyopathy, with global left ventricular systolic and diastolic dysfunction that improve or resolve after the adrenergic insult is removed.16
Conditions that warrant further evaluation or that may suggest pheochromocytoma are malignant hypertension, hypertensive encephalopathy, ischemic stroke, subarachnoid hemorrhage, acute pulmonary edema, angina pectoris, myocardial infarction, aortic dissection, and kidney injury.
When to suspect pheochromocytoma
Pheochromocytoma should be suspected in a patient with resistant hypertension, family history, or imaging findings that suggest an adrenal mass with a heterogeneous appearance. The diagnostic algorithm follows the same pathway as for the evaluation of an incidentally found adrenal mass, with determination of its dimension and characteristics by CT or MRI, and with biochemical testing of urine catecholamines, plasma free metanephrines, renin, aldosterone, and cortisol.
The diagnosis of pheochromocytoma is established by obtaining fractionated metanephrines and catecholamines in a 24-hour urine collection (sensitivity 90%, specificity 98%). Analysis of plasma metanephrines has a higher sensitivity (97%) but lower specificity (85%).17 The combination of typical signs, symptoms, and laboratory findings makes the diagnosis likely, especially in combination with a unilateral adrenal mass.
Laparoscopic surgery after medical preparation for active tumors
If the mass appears benign and not biochemically hyperactive, then follow-up at 1 year is recommended, with repeat testing. Surgical evaluation and intervention is recommended for lesions that appear malignant or that are biochemically active and clinically symptomatic.9
Preoperative hemodynamic control is essential in the management of pheochromocytoma to prevent or minimize hemodynamic changes that can be driven by increased catecholamines. Control is typically achieved with initial alpha-blockade and then beta-blockade to avoid worsening hypertension and to prevent an acute hypertensive crisis during surgical intervention. Phenoxybenzamine, the mainstay of therapy, is a nonselective alpha-blocker with a long duration of action that requires titration over several days up to 3 weeks.
A selective alpha-1-blocker such as doxazosin can be used to control postoperative hypotension, as it has a shorter half-life than phenoxybenzamine. Alternative strategies include calcium channel blockers, centrally acting sympathetic blockers, and magnesium.18
Laparoscopic adrenalectomy by an experienced surgeon after excellent medical preparation is often considered the treatment of choice, but for larger or malignant masses, an open procedure is recommended. The risk of perioperative morbidity and death can be reduced by adequate medical management. With successful surgical resection, the long-term prognosis is favorable.
- Calhoun DA, Jones D, Textor S, et al. Resistant hypertension: diagnosis, evaluation, and treatment. A scientific statement from the American Heart Association Professional Education Committee of the Council for High Blood Pressure Research. Hypertension 2008; 51:1403–1419.
- Kumar N, Calhoun DA, Dudenbostel T. Management of patients with resistant hypertension: current treatment options. Integr Blood Press Control 2013; 6:139–151.
- Pedrosa RP, Drager LF, Gonzaga CC, et al. Obstructive sleep apnea: the most common secondary cause of hypertension associated with resistant hypertension. Hypertension 2011; 58:811–817.
- Marcus JA, Pothineni A, Marcus CZ, Bisognano JD. The role of obesity and obstructive sleep apnea in the pathogenesis and treatment of resistant hypertension. Curr Hypertens Rep 2014; 16:411.
- Calhoun DA, Nishizaka MK, Zaman MA, Thakkar RB, Weissmann P. Hyperaldosteronism among black and white subjects with resistant hypertension. Hypertension 2002; 40:892–896.
- Young WF Clinical practice. The incidentally discovered adrenal mass. N Engl J Med 2007; 356:601–610.
- Lin M, Wong V, Yap J, Jin R, Leong P, Campbell P. FDG PET in the evaluation of phaeochromocytoma: a correlative study with MIBG scintigraphy and Ki-67 proliferative index. Clin Imaging 2013; 37:1084–1088.
- Raja A, Leung K, Stamm M, Girgis S, Low G. Multimodality imaging findings of pheochromocytoma with associated clinical and biochemical features in 53 patients with histologically confirmed tumors. AJR Am J Roentgenol 2013; 201:825–833.
- Nieman LK. Approach to the patient with an adrenal incidentaloma. J Clin Endocrinol Metab 2010; 95:4106–4113.
- Stolk RF, Bakx C, Mulder J, Timmers HJ, Lenders JW. Is the excess cardiovascular morbidity in pheochromocytoma related to blood pressure or to catecholamines? J Clin Endocrinol Metab 2013; 98:1100–1106.
- Grumbach MM, Biller BM, Braunstein GD, et al. Management of the clinically inapparent adrenal mass (‘incidentaloma’). Ann Intern Med 2003; 138:424–429.
- Lentschener C, Gaujoux S, Tesniere A, Dousset B. Point of controversy: perioperative care of patients undergoing pheochromocytoma removal—time for a reappraisal? Eur J Endocrinol 2011; 165:365–373.
- Bryant J, Farmer J, Kessler LJ, Townsend RR, Nathanson KL. Pheochromocytoma: the expanding genetic differential diagnosis. J Natl Cancer Inst 2003; 95:1196–1204.
- Lee P, Leonard J. Textbook on endocrinology. BMJ 1994; 308:1512.
- Fishbein L, Merrill S, Fraker DL, Cohen DL, Nathanson KL. Inherited mutations in pheochromocytoma and paraganglioma: why all patients should be offered genetic testing. Ann Surg Oncol 2013; 20:1444–1450.
- Agarwal G, Sadacharan D, Kapoor A, et al. Cardiovascular dysfunction and catecholamine cardiomyopathy in pheochromocytoma patients and their reversal following surgical cure: results of a prospective case-control study. Surgery 2011; 150:1202–1211.
- Sawka AM, Jaeschke R, Singh RJ, Young WF A comparison of biochemical tests for pheochromocytoma: measurement of fractionated plasma metanephrines compared with the combination of 24-hour urinary metanephrines and catecholamines. J Clin Endocrinol Metab 2003; 88:553–558.
- Domi R, Laho H. Management of pheochromocytoma: old ideas and new drugs. Niger J Clin Pract 2012; 15:253–257.
- Calhoun DA, Jones D, Textor S, et al. Resistant hypertension: diagnosis, evaluation, and treatment. A scientific statement from the American Heart Association Professional Education Committee of the Council for High Blood Pressure Research. Hypertension 2008; 51:1403–1419.
- Kumar N, Calhoun DA, Dudenbostel T. Management of patients with resistant hypertension: current treatment options. Integr Blood Press Control 2013; 6:139–151.
- Pedrosa RP, Drager LF, Gonzaga CC, et al. Obstructive sleep apnea: the most common secondary cause of hypertension associated with resistant hypertension. Hypertension 2011; 58:811–817.
- Marcus JA, Pothineni A, Marcus CZ, Bisognano JD. The role of obesity and obstructive sleep apnea in the pathogenesis and treatment of resistant hypertension. Curr Hypertens Rep 2014; 16:411.
- Calhoun DA, Nishizaka MK, Zaman MA, Thakkar RB, Weissmann P. Hyperaldosteronism among black and white subjects with resistant hypertension. Hypertension 2002; 40:892–896.
- Young WF Clinical practice. The incidentally discovered adrenal mass. N Engl J Med 2007; 356:601–610.
- Lin M, Wong V, Yap J, Jin R, Leong P, Campbell P. FDG PET in the evaluation of phaeochromocytoma: a correlative study with MIBG scintigraphy and Ki-67 proliferative index. Clin Imaging 2013; 37:1084–1088.
- Raja A, Leung K, Stamm M, Girgis S, Low G. Multimodality imaging findings of pheochromocytoma with associated clinical and biochemical features in 53 patients with histologically confirmed tumors. AJR Am J Roentgenol 2013; 201:825–833.
- Nieman LK. Approach to the patient with an adrenal incidentaloma. J Clin Endocrinol Metab 2010; 95:4106–4113.
- Stolk RF, Bakx C, Mulder J, Timmers HJ, Lenders JW. Is the excess cardiovascular morbidity in pheochromocytoma related to blood pressure or to catecholamines? J Clin Endocrinol Metab 2013; 98:1100–1106.
- Grumbach MM, Biller BM, Braunstein GD, et al. Management of the clinically inapparent adrenal mass (‘incidentaloma’). Ann Intern Med 2003; 138:424–429.
- Lentschener C, Gaujoux S, Tesniere A, Dousset B. Point of controversy: perioperative care of patients undergoing pheochromocytoma removal—time for a reappraisal? Eur J Endocrinol 2011; 165:365–373.
- Bryant J, Farmer J, Kessler LJ, Townsend RR, Nathanson KL. Pheochromocytoma: the expanding genetic differential diagnosis. J Natl Cancer Inst 2003; 95:1196–1204.
- Lee P, Leonard J. Textbook on endocrinology. BMJ 1994; 308:1512.
- Fishbein L, Merrill S, Fraker DL, Cohen DL, Nathanson KL. Inherited mutations in pheochromocytoma and paraganglioma: why all patients should be offered genetic testing. Ann Surg Oncol 2013; 20:1444–1450.
- Agarwal G, Sadacharan D, Kapoor A, et al. Cardiovascular dysfunction and catecholamine cardiomyopathy in pheochromocytoma patients and their reversal following surgical cure: results of a prospective case-control study. Surgery 2011; 150:1202–1211.
- Sawka AM, Jaeschke R, Singh RJ, Young WF A comparison of biochemical tests for pheochromocytoma: measurement of fractionated plasma metanephrines compared with the combination of 24-hour urinary metanephrines and catecholamines. J Clin Endocrinol Metab 2003; 88:553–558.
- Domi R, Laho H. Management of pheochromocytoma: old ideas and new drugs. Niger J Clin Pract 2012; 15:253–257.