Dementia and Cognitive Impairment Among U.S. Veterans With a History of MDD or PTSD: A Retrospective Cohort Study Based on Sex and Race.

The aim of this study was to examine major depressive disorder (MDD) and posttraumatic stress disorder (PTSD) diagnosed at age < 55 as predictors, and sex and race as potential moderators, of dementia and other forms of cognitive impairment. Veterans ( = 4,800) aged ⩾ 56 years were grouped by psychiatric history, sex, and race. Hierarchical and stepwise regression were employed to determine significant predictors. MDD and PTSD were associated with almost double the risk for developing dementia or cognitive impairment at age ⩾ 56. Sex, as a moderator, had small effects whereas race increased the risk almost twofold for Black veterans, given the presence of MDD history. MDD and PTSD act as significant risk factors for dementia and other forms of cognitive impairment, and Black veterans, given a history of MDD, may be at an increased risk. An important endeavor for future research is to examine how this risk may vary across dementia subtypes and related conditions.