TORONTO—Posttraumatic stress disorder (PTSD) is a risk factor for dementia in men and women. Among men, PTSD is associated with a 90% increased risk of incident dementia, according to research presented at the Alzheimer’s Association International Conference.
Women and PTSD
Previous studies indicate that women are at a higher risk of PTSD, but little research is available concerning the risk of dementia in women diagnosed with PTSD. “They are more likely to experience trauma, maybe from domestic abuse, violence, [and] rape … so I think this is a huge area that needs research,” said Jason Flatt, PhD, MPH, Assistant Professor of Health and Aging at the University of California, San Francisco. To analyze the link between PTSD and dementia in both genders, Dr. Flatt and colleagues examined data from a diverse population.
“The objectives of the study were to look at the effect of PTSD on the risk of dementia over 13 years among older men and women and see if the association is explained by medical comorbidities like depression and traumatic brain injury,” said Dr. Flatt.
Diverse Population Sample
Participants were selected from the Kaiser Permanente Northern California healthcare system and were age 60 or older in January 2002. Women made up 54.7% of the population, 68% of the population was white, 5.5% was black, 6.5% was Hispanic, and 9% was Asian. Mean age at baseline was 71. The dementia diagnoses were collected from medical records for January 1, 2002 through December 31, 2014. Mean follow-up was approximately eight years.
Investigators evaluated the association between PTSD and dementia using gender-modified models adjusted for age, race, diabetes, and stroke, with censoring for death and gaps in health coverage of greater than 90 days. In all, 1,147 patients were diagnosed with PTSD. In addition, researchers found that during the 13-year follow-up period, 11.8% of subjects received a diagnosis of dementia.
People with PTSD were more likely to experience traumatic brain injuries and depression. Patients with PTSD also had a 56% increased risk of developing dementia, compared with controls without PTSD. Men with PTSD had a 90% increase in dementia risk, and women with PTSD had a 41% increase in dementia risk, compared with controls.
“This is the first large study of PTSD and risk of dementia in women, and results suggest that PTSD is a risk factor in both genders,” said Dr. Flatt.
Strengths of this study include its longitudinal design, diverse sample, and 13-year follow-up period. Dementia was diagnosed by physicians, however, and as a result, researchers were unable to observe dementia subtypes.
“Future research should think about these mechanisms and how to link and better understand how PTSD may be involved in dementia risk,” said Dr. Flatt.
Suggested Reading
Wang TY, Wei HT, Liou YJ et al. Risk for developing dementia among patients with posttraumatic stress disorder: A nationwide longitudinal study. J Affect Disord. 2016 Aug 16 [Epub ahead of print].
McCartney JR, Severson K. Sexual violence, post-traumatic stress disorder and dementia. J Am Geriatr Soc. 1997; 45(1):76-78.