Presented at this year's Alzheimer's Association International Conference in Paris, France, a seven year study of veterans over 55 found that the veterans with TBI were twice as likely to develop dementia over that 7 year period of time, with 15% of the TBI veterans vs 7% of non-TBI veterans developing dementia.
"[The findings] suggest TBI may predispose people to earlier manifestation of [dementia] symptoms and raises hope that treatment or rehabilitation may have a role in preventing downstream dementia," says Kristine Yaffe, MD, professor of psychiatry and epidemiology, University of California, San Francisco and director of the Memory Disorders Program at the San Francisco Veterans Affairs Medical Center.
According to Dr. Yaffe, the most plausible explanation for the relationship between increased dementia in TBI victims is that diffuse axonal injury, or swelling of the axons that form connections between the neurons, would disrupt neuronal communication.
Clinicians need to recognize TBI as a major risk factor for dementia, and individuals who have sustained a head injury constitute a group that should "probably be followed very carefully as they age and be screened for dementia and other cognitive problems," Dr. Yaffe said.
