Older veterans with post-traumatic stress disorder were almost twice as likely to develop dementia as veterans without PTSD in a study of more than 180,000 veterans led by researchers at the San Francisco VA Medical Center and the University of California, San Francisco.
The results were announced at the Alzheimer’s Association 2009 International Conference on Alzheimer’s Disease in Vienna, Austria by lead author Kristine Yaffe, MD, chief of geriatric psychiatry at SFVAMC and associate chair of research for psychiatry and professor of psychiatry, neurology, and epidemiology and biostatistics at UCSF.
“These findings are important because PTSD has become a common consequence of combat and exposure to trauma,” says Yaffe. She notes that other studies have suggested that PTSD occurs in 15 to 20 percent of military personnel who have served in Iraq and Afghanistan.
Using data from the Department of Veterans Affairs National Patient Care Database, the researchers analyzed the 1997-2000 records of 53,155 veterans diagnosed with PTSD and 127,938 without PTSD. None of the veterans were diagnosed as demented when the study began. Their average age was 68.8 years, and 97 percent were male.
The veterans were then followed from 2001 to 2007 and assessed for development of dementia according to standard medical diagnosis codes. By 2007, veterans with PTSD had a dementia rate of 10.6 percent, while veterans without PTSD had a dementia rate of 6.6 percent.
The association between PTSD and dementia remained after adjustment for demographics, medical and psychiatric conditions, and number of clinic visits, and after exclusion of subjects with traumatic brain injury, substance abuse, or depression.
“It is critical that we identify the mechanisms linking these two important disorders,” says Yaffe, who observes that, according to current projections, Alzheimer’s disease will more than double in the United States by 2047, increasing from less than four million cases today to more than eight million.
“We would like to replicate this study among non-veterans,” she says.
Co-authors of the study are Eric Vittinghoff, PhD, of UCSF, and Karla Lindquist, MS, Deborah E. Barnes, PhD, Kenneth E. Covinsky, MD, Thomas Neylan, MD, Molly Kluse, BA, and Charles Marmar, MD, of SFVAMC and UCSF.
The study was supported by funds from the US Army Telemedicine and Advanced Technology Research Center that were administered by the Northern California Institute for Research and Education.
NCIRE - The Veterans Health Research Institute is the largest research institute associated with a VA medical center. Its mission is to improve the health and well-being of veterans and the general public by supporting a world-class biomedical research program conducted by the UCSF faculty at SFVAMC.
SFVAMC has the largest medical research program in the national VA system, with more than 200 research scientists, all of whom are faculty members at UCSF.
UCSF is a leading university dedicated to promoting health worldwide through advanced biomedical research, graduate-level education in the life sciences and health professions, and excellence in patient care.