TBI May Double Dementia Risk

PARIS – Traumatic brain injury may double the risk of developing dementia, according to findings from a study of more than 280,000 U.S. veterans.

The risk of dementia over 7 years was 15.3% in 4,902 veterans who had a traumatic brain injury (TBI) diagnosis in 1997-2000, compared with 6.8% in those without a TBI diagnosis. The comparison yielded a hazard ratio of 2.3 for those with any TBI diagnosis after adjustment for age, sex, race, and multiple medical and psychiatric conditions.

The difference was statistically significant for all TBI types, including intracranial injury (the most common form, which accounted for 40% of the injuries among the veterans) as well as for concussion, postconcussion syndrome, head fracture, and unspecified head injury, Dr. Kristine Yaffe and her colleagues reported in a poster on July 18 at the International Conference on Alzheimer’s Disease.

The findings also offer some hope that early treatment and rehabilitation after TBI could help ward off dementia, and they underscore the need for monitoring affected older adults for signs of cognitive impairment following a TBI, Dr. Yaffe said at the conference.

"The issue is important because TBI is very common," according to Dr. Yaffe, professor of psychiatry, neurology, and epidemiology at the University of California, San Francisco, who noted that the condition is common in the general population as well as among veterans.

About 1.7 million people experience a TBI each year in the United States, most often as a result of falls and car crashes, according to data from the U.S. Centers for Disease Control and Prevention. About 2% of the veterans included in this study had a TBI diagnosis during the study period.

In fact, TBI is known as the "signature wound" incurred by soldiers involved in conflicts in Iraq and Afghanistan, because it accounts for 22% of casualties and 59% of blast-related injuries. Findings from this and prior studies that suggest an association between such injuries and the development of symptomatic dementia raise concern about potential long-term consequences for affected veterans, as well as for older adults in the general population who experience a TBI, said Dr. Yaffe, who is also director of the memory disorders clinic at the San Francisco VA Medical Center.

That is particularly true because amyloid plaques similar to those seen in the brains of Alzheimer’s patients are also present in nearly a third of TBI patients who don’t survive their injuries.

"It is possible that these injuries result in the death of axons and neurons, even after a single TBI. Loss of axons and neurons could result in earlier manifestation of Alzheimer’s symptoms," the researchers said in a statement regarding the findings.

Veterans included in the study were aged 55 years or older with no dementia diagnosis at baseline. Each veteran had received care through the Veterans Health Administration, had at least one visit during 1997-2000, and had a follow-up visit from 2001-2007.

Dr. Yaffe’s research was funded by the U.S. Department of Defense. She had no other relevant disclosures.

PARIS – Traumatic brain injury may double the risk of developing dementia, according to findings from a study of more than 280,000 U.S. veterans.

The risk of dementia over 7 years was 15.3% in 4,902 veterans who had a traumatic brain injury (TBI) diagnosis in 1997-2000, compared with 6.8% in those without a TBI diagnosis. The comparison yielded a hazard ratio of 2.3 for those with any TBI diagnosis after adjustment for age, sex, race, and multiple medical and psychiatric conditions.

The difference was statistically significant for all TBI types, including intracranial injury (the most common form, which accounted for 40% of the injuries among the veterans) as well as for concussion, postconcussion syndrome, head fracture, and unspecified head injury, Dr. Kristine Yaffe and her colleagues reported in a poster on July 18 at the International Conference on Alzheimer’s Disease.

The findings also offer some hope that early treatment and rehabilitation after TBI could help ward off dementia, and they underscore the need for monitoring affected older adults for signs of cognitive impairment following a TBI, Dr. Yaffe said at the conference.

"The issue is important because TBI is very common," according to Dr. Yaffe, professor of psychiatry, neurology, and epidemiology at the University of California, San Francisco, who noted that the condition is common in the general population as well as among veterans.

About 1.7 million people experience a TBI each year in the United States, most often as a result of falls and car crashes, according to data from the U.S. Centers for Disease Control and Prevention. About 2% of the veterans included in this study had a TBI diagnosis during the study period.

In fact, TBI is known as the "signature wound" incurred by soldiers involved in conflicts in Iraq and Afghanistan, because it accounts for 22% of casualties and 59% of blast-related injuries. Findings from this and prior studies that suggest an association between such injuries and the development of symptomatic dementia raise concern about potential long-term consequences for affected veterans, as well as for older adults in the general population who experience a TBI, said Dr. Yaffe, who is also director of the memory disorders clinic at the San Francisco VA Medical Center.

That is particularly true because amyloid plaques similar to those seen in the brains of Alzheimer’s patients are also present in nearly a third of TBI patients who don’t survive their injuries.

"It is possible that these injuries result in the death of axons and neurons, even after a single TBI. Loss of axons and neurons could result in earlier manifestation of Alzheimer’s symptoms," the researchers said in a statement regarding the findings.

Veterans included in the study were aged 55 years or older with no dementia diagnosis at baseline. Each veteran had received care through the Veterans Health Administration, had at least one visit during 1997-2000, and had a follow-up visit from 2001-2007.

Dr. Yaffe’s research was funded by the U.S. Department of Defense. She had no other relevant disclosures.

PARIS – Traumatic brain injury may double the risk of developing dementia, according to findings from a study of more than 280,000 U.S. veterans.

The risk of dementia over 7 years was 15.3% in 4,902 veterans who had a traumatic brain injury (TBI) diagnosis in 1997-2000, compared with 6.8% in those without a TBI diagnosis. The comparison yielded a hazard ratio of 2.3 for those with any TBI diagnosis after adjustment for age, sex, race, and multiple medical and psychiatric conditions.

The difference was statistically significant for all TBI types, including intracranial injury (the most common form, which accounted for 40% of the injuries among the veterans) as well as for concussion, postconcussion syndrome, head fracture, and unspecified head injury, Dr. Kristine Yaffe and her colleagues reported in a poster on July 18 at the International Conference on Alzheimer’s Disease.

The findings also offer some hope that early treatment and rehabilitation after TBI could help ward off dementia, and they underscore the need for monitoring affected older adults for signs of cognitive impairment following a TBI, Dr. Yaffe said at the conference.

"The issue is important because TBI is very common," according to Dr. Yaffe, professor of psychiatry, neurology, and epidemiology at the University of California, San Francisco, who noted that the condition is common in the general population as well as among veterans.

About 1.7 million people experience a TBI each year in the United States, most often as a result of falls and car crashes, according to data from the U.S. Centers for Disease Control and Prevention. About 2% of the veterans included in this study had a TBI diagnosis during the study period.

In fact, TBI is known as the "signature wound" incurred by soldiers involved in conflicts in Iraq and Afghanistan, because it accounts for 22% of casualties and 59% of blast-related injuries. Findings from this and prior studies that suggest an association between such injuries and the development of symptomatic dementia raise concern about potential long-term consequences for affected veterans, as well as for older adults in the general population who experience a TBI, said Dr. Yaffe, who is also director of the memory disorders clinic at the San Francisco VA Medical Center.

That is particularly true because amyloid plaques similar to those seen in the brains of Alzheimer’s patients are also present in nearly a third of TBI patients who don’t survive their injuries.

"It is possible that these injuries result in the death of axons and neurons, even after a single TBI. Loss of axons and neurons could result in earlier manifestation of Alzheimer’s symptoms," the researchers said in a statement regarding the findings.

Veterans included in the study were aged 55 years or older with no dementia diagnosis at baseline. Each veteran had received care through the Veterans Health Administration, had at least one visit during 1997-2000, and had a follow-up visit from 2001-2007.

Dr. Yaffe’s research was funded by the U.S. Department of Defense. She had no other relevant disclosures.