If you've ever suffered a concussion, a new study suggests you may have a higher risk of developing Alzheimer's disease—or not. Mayo Clinic researchers performed brain scans on 141 people in their 70s and 80s who had memory problems and 448 who didn't. Some 18% and 17%, respectively, reported at one time suffering a brain injury in which they lost consciousness or memory. The latter group's scans came back normal, head injury or not. But the group with memory issues and a previous concussion were five times more likely to have an Alzheimer's-associated plaque buildup in the brain, the study author explains, per HealthDay News.
Since both groups had the same rate of injury and only some showed a buildup of the protein beta amyloid, the findings show the link between head trauma and the plaque is complex and not all brain injuries lead to the disease. "If you do hit your head, it doesn't mean you are going to develop Alzheimer's," the study author says, but "it may increase your risk." A medical director agrees, and tells USA Today, "In my view, these findings are consistent with the idea that traumatic brain injury may lead to amyloid accumulation and Alzheimer's disease."