In a study of US veterans, scientists from Boston University found that a head injury or post-traumatic stress disorder can increase the risk of developing Alzheimer’s disease. Research published Alzheimer’s and Dementia: Journal of the Alzheimer’s Association.
Researchers have found that veterans with post-traumatic stress disorder and survivors of traumatic brain injury have a 6% higher risk of developing Alzheimer’s disease than other veterans.
Previous studies have shown that the ε4 variant of the APOE gene increases the risk of developing Alzheimer’s disease, with the risk increasing with age. In addition, if both parents are carriers of the mutation, the person will inherit two copies of the defective gene – in which case the risk of Alzheimer’s disease will be even higher. The authors found that these veterans had an 11% greater risk of dementia (compared to normal carriers of two copies of ε4) if they had PTSD or a head injury.
Analysis is based on data from Virginia’s Million Veteran Program (MVP). This program aims to examine how genes, lifestyle and combat experience affect health. More than one million people participated in the program in total.