Posttraumatic Headache More Common When Injury Is Mild

LOS ANGELES – The likelihood of headache after traumatic brain injury was inversely related to the severity of injury in a longitudinal study of 598 patients.

The patients with mild injury were about 70% more likely than were their counterparts with moderate or severe injury to develop new headache or have a worsening of preexisting headache over the next year, first author Dr. Sylvia Lucas reported at the annual meeting of the American Headache Society.

The majority of headaches were migraine or probable migraine according to the ICHD-2 (International Classification of Headache Disorders, second edition) system, but a large share – roughly a quarter – had features that defied classification. Patients with preexisting headache and female patients had a higher risk of posttraumatic headache.

"Using symptom-based criteria for headache after TBI [traumatic brain injury] hopefully may serve as a framework from which to provide evidence-based treatment," commented Dr. Lucas, clinical professor of neurology, rehabilitation medicine, and neurosurgery at the University of Washington in Seattle.

Session attendee Dr. Werner Becker of the University of Calgary (Alta.) asked, "Any thoughts as to why the patients with milder injuries have more headache?"

"I don’t know. It has to have something to do with the mechanics of the hit, I suspect," Dr. Lucas replied. "We’re just now trying to look at the types of injury. We’re trying to separate subarachnoid hemorrhage, depressed skull fracture, intracerebral hemorrhage, and trying to look at how they relate to the chronicity of the headache. But, as of now, I can’t answer that."

Dr. James R. Couch of the University of Oklahoma, Oklahoma City, who also attended the session, noted that he and his colleagues found a similar pattern in a previous study. "I was very gratified to see that what you are finding is the less severely injured people seem to have a greater propensity for headache," he said. "Maybe the severe brain injury takes out some kind of center that is involved in generating headache, whereas the mild head injury just irritates it."

The investigators studied a single-center cohort of 220 patients with mild TBI who were enrolled within a week of injury and a seven-center cohort of 378 patients with moderate to severe TBI who were admitted to inpatient rehabilitation facilities. All patients were evaluated with the same questionnaire, in person at baseline, and prospectively by telephone over a year, to gain a better understanding of headache incidence, characteristics, and predictors, and treatment effectiveness.

"We feel that the ICHD-2 criteria, both in the civilian and military populations, really don’t contribute to treatment planning," Dr. Lucas commented. "They also don’t account for the latency of posttraumatic headache following trauma," with experience suggesting that almost a third of headache cases do not come to clinical attention until more than 1 week after the injury, even though that is the window typically used to define posttraumatic headache.

Patients in both groups were about 43 years old, on average, and roughly three-quarters each were male and white, and had completed high school. The leading cause of injury was vehicular accident (58%) followed by falls (25%).

Study results showed that the mild TBI group and the moderate or severe TBI group had an identical prevalence of headache before injury (17%). But the former had a higher incidence of new or worsened headache at baseline (56% vs. 40%), at 3 months (63% vs. 37%), at 6 months (69% vs. 33%), and at 12 months (58% vs. 34%).

Headache was classified according to ICHD-2 criteria for primary headache, with only a single class permitted per patient, based on the predominant features, according to Dr. Lucas. "The idea behind classification of a secondary headache using primary headache criteria is really to try to find some defining features that may allow us to do what we want in the future, which is to get some evidence-based medicine treatment or management protocols," she explained.

At all time points and in both groups, the largest share of headaches (39%-67%) was of the migraine or probable migraine type. Tension headaches were the next most common type. "Surprisingly, cervicogenic was not very [common], particularly considering that many of these were motor vehicle accidents and probably involved whiplash-type injuries," she observed.

Roughly a quarter of headaches were unclassifiable. "We felt that rather than trying to use a shoehorn to fit the headache into a classification, if it didn’t fit, we just stayed with it and deemed it unclassifiable," Dr. Lucas commented.

In both the mild TBI group and the moderate to severe TBI group, the migraine and probable migraine headaches, in addition to being most common, were more likely than the other types of headache to occur daily or several times weekly.

Also, in both groups, patients who had a prior history of headache and female patients were more likely to have headache at follow-up. For example, in the mild TBI group, about 70% of patients who had preexisting headache had headache at all time points during follow-up, compared with about 50% of patients who did not have preexisting headache.

Dr. Lucas disclosed no relevant conflicts of interest.

LOS ANGELES – The likelihood of headache after traumatic brain injury was inversely related to the severity of injury in a longitudinal study of 598 patients.

The patients with mild injury were about 70% more likely than were their counterparts with moderate or severe injury to develop new headache or have a worsening of preexisting headache over the next year, first author Dr. Sylvia Lucas reported at the annual meeting of the American Headache Society.

The majority of headaches were migraine or probable migraine according to the ICHD-2 (International Classification of Headache Disorders, second edition) system, but a large share – roughly a quarter – had features that defied classification. Patients with preexisting headache and female patients had a higher risk of posttraumatic headache.

"Using symptom-based criteria for headache after TBI [traumatic brain injury] hopefully may serve as a framework from which to provide evidence-based treatment," commented Dr. Lucas, clinical professor of neurology, rehabilitation medicine, and neurosurgery at the University of Washington in Seattle.

Session attendee Dr. Werner Becker of the University of Calgary (Alta.) asked, "Any thoughts as to why the patients with milder injuries have more headache?"

"I don’t know. It has to have something to do with the mechanics of the hit, I suspect," Dr. Lucas replied. "We’re just now trying to look at the types of injury. We’re trying to separate subarachnoid hemorrhage, depressed skull fracture, intracerebral hemorrhage, and trying to look at how they relate to the chronicity of the headache. But, as of now, I can’t answer that."

Dr. James R. Couch of the University of Oklahoma, Oklahoma City, who also attended the session, noted that he and his colleagues found a similar pattern in a previous study. "I was very gratified to see that what you are finding is the less severely injured people seem to have a greater propensity for headache," he said. "Maybe the severe brain injury takes out some kind of center that is involved in generating headache, whereas the mild head injury just irritates it."

The investigators studied a single-center cohort of 220 patients with mild TBI who were enrolled within a week of injury and a seven-center cohort of 378 patients with moderate to severe TBI who were admitted to inpatient rehabilitation facilities. All patients were evaluated with the same questionnaire, in person at baseline, and prospectively by telephone over a year, to gain a better understanding of headache incidence, characteristics, and predictors, and treatment effectiveness.

"We feel that the ICHD-2 criteria, both in the civilian and military populations, really don’t contribute to treatment planning," Dr. Lucas commented. "They also don’t account for the latency of posttraumatic headache following trauma," with experience suggesting that almost a third of headache cases do not come to clinical attention until more than 1 week after the injury, even though that is the window typically used to define posttraumatic headache.

Patients in both groups were about 43 years old, on average, and roughly three-quarters each were male and white, and had completed high school. The leading cause of injury was vehicular accident (58%) followed by falls (25%).

Study results showed that the mild TBI group and the moderate or severe TBI group had an identical prevalence of headache before injury (17%). But the former had a higher incidence of new or worsened headache at baseline (56% vs. 40%), at 3 months (63% vs. 37%), at 6 months (69% vs. 33%), and at 12 months (58% vs. 34%).

Headache was classified according to ICHD-2 criteria for primary headache, with only a single class permitted per patient, based on the predominant features, according to Dr. Lucas. "The idea behind classification of a secondary headache using primary headache criteria is really to try to find some defining features that may allow us to do what we want in the future, which is to get some evidence-based medicine treatment or management protocols," she explained.

At all time points and in both groups, the largest share of headaches (39%-67%) was of the migraine or probable migraine type. Tension headaches were the next most common type. "Surprisingly, cervicogenic was not very [common], particularly considering that many of these were motor vehicle accidents and probably involved whiplash-type injuries," she observed.

Roughly a quarter of headaches were unclassifiable. "We felt that rather than trying to use a shoehorn to fit the headache into a classification, if it didn’t fit, we just stayed with it and deemed it unclassifiable," Dr. Lucas commented.

In both the mild TBI group and the moderate to severe TBI group, the migraine and probable migraine headaches, in addition to being most common, were more likely than the other types of headache to occur daily or several times weekly.

Also, in both groups, patients who had a prior history of headache and female patients were more likely to have headache at follow-up. For example, in the mild TBI group, about 70% of patients who had preexisting headache had headache at all time points during follow-up, compared with about 50% of patients who did not have preexisting headache.

Dr. Lucas disclosed no relevant conflicts of interest.

LOS ANGELES – The likelihood of headache after traumatic brain injury was inversely related to the severity of injury in a longitudinal study of 598 patients.

The patients with mild injury were about 70% more likely than were their counterparts with moderate or severe injury to develop new headache or have a worsening of preexisting headache over the next year, first author Dr. Sylvia Lucas reported at the annual meeting of the American Headache Society.

The majority of headaches were migraine or probable migraine according to the ICHD-2 (International Classification of Headache Disorders, second edition) system, but a large share – roughly a quarter – had features that defied classification. Patients with preexisting headache and female patients had a higher risk of posttraumatic headache.

"Using symptom-based criteria for headache after TBI [traumatic brain injury] hopefully may serve as a framework from which to provide evidence-based treatment," commented Dr. Lucas, clinical professor of neurology, rehabilitation medicine, and neurosurgery at the University of Washington in Seattle.

Session attendee Dr. Werner Becker of the University of Calgary (Alta.) asked, "Any thoughts as to why the patients with milder injuries have more headache?"

"I don’t know. It has to have something to do with the mechanics of the hit, I suspect," Dr. Lucas replied. "We’re just now trying to look at the types of injury. We’re trying to separate subarachnoid hemorrhage, depressed skull fracture, intracerebral hemorrhage, and trying to look at how they relate to the chronicity of the headache. But, as of now, I can’t answer that."

Dr. James R. Couch of the University of Oklahoma, Oklahoma City, who also attended the session, noted that he and his colleagues found a similar pattern in a previous study. "I was very gratified to see that what you are finding is the less severely injured people seem to have a greater propensity for headache," he said. "Maybe the severe brain injury takes out some kind of center that is involved in generating headache, whereas the mild head injury just irritates it."

The investigators studied a single-center cohort of 220 patients with mild TBI who were enrolled within a week of injury and a seven-center cohort of 378 patients with moderate to severe TBI who were admitted to inpatient rehabilitation facilities. All patients were evaluated with the same questionnaire, in person at baseline, and prospectively by telephone over a year, to gain a better understanding of headache incidence, characteristics, and predictors, and treatment effectiveness.

"We feel that the ICHD-2 criteria, both in the civilian and military populations, really don’t contribute to treatment planning," Dr. Lucas commented. "They also don’t account for the latency of posttraumatic headache following trauma," with experience suggesting that almost a third of headache cases do not come to clinical attention until more than 1 week after the injury, even though that is the window typically used to define posttraumatic headache.

Patients in both groups were about 43 years old, on average, and roughly three-quarters each were male and white, and had completed high school. The leading cause of injury was vehicular accident (58%) followed by falls (25%).

Study results showed that the mild TBI group and the moderate or severe TBI group had an identical prevalence of headache before injury (17%). But the former had a higher incidence of new or worsened headache at baseline (56% vs. 40%), at 3 months (63% vs. 37%), at 6 months (69% vs. 33%), and at 12 months (58% vs. 34%).

Headache was classified according to ICHD-2 criteria for primary headache, with only a single class permitted per patient, based on the predominant features, according to Dr. Lucas. "The idea behind classification of a secondary headache using primary headache criteria is really to try to find some defining features that may allow us to do what we want in the future, which is to get some evidence-based medicine treatment or management protocols," she explained.

At all time points and in both groups, the largest share of headaches (39%-67%) was of the migraine or probable migraine type. Tension headaches were the next most common type. "Surprisingly, cervicogenic was not very [common], particularly considering that many of these were motor vehicle accidents and probably involved whiplash-type injuries," she observed.

Roughly a quarter of headaches were unclassifiable. "We felt that rather than trying to use a shoehorn to fit the headache into a classification, if it didn’t fit, we just stayed with it and deemed it unclassifiable," Dr. Lucas commented.

In both the mild TBI group and the moderate to severe TBI group, the migraine and probable migraine headaches, in addition to being most common, were more likely than the other types of headache to occur daily or several times weekly.

Also, in both groups, patients who had a prior history of headache and female patients were more likely to have headache at follow-up. For example, in the mild TBI group, about 70% of patients who had preexisting headache had headache at all time points during follow-up, compared with about 50% of patients who did not have preexisting headache.

Dr. Lucas disclosed no relevant conflicts of interest.