Abstract
Posttraumatic stress disorder (PTSD) is associated with both cognitive deficits and an increased risk of dementia. Few studies, however, have examined the association between PTSD and cognitive decline in the context of parameters important to brain aging, including health conditions and genetics (e.g., APOE Ɛ4 status). National Alzheimer's Coordinating Center data were used to investigate the associations between lifetime PTSD status and working memory, immediate and delayed episodic memory, and executive functions over 7 years in 11,961 older adults with (n = 179) and without PTSD. Inverse probability weighting was used to mitigate confounding variables. Linear mixed-effects models were fit to weighted data. Sex, race, and APOE Ɛ4 status were examined as moderators. Lifetime PTSD was associated with an additional 0.031 standard deviations of decline in working memory annually, B = -0.031, 95% CI [-0.055, -0.007]. There was no significant PTSD x Time interaction for other cognitive domains. Sex moderated the associations between PTSD and working memory, B = 0.067, SE = 0.03, and delayed recall, B = 0.063, SE = 0.03, such that, among individuals with PTSD, men demonstrated faster decline than women. APOE Ɛ4 moderated the associations between PTSD and delayed recall, B = -0.106, SE = 0.03, and executive functions, B = 0.061, SE = 0.02; among individuals with PTSD, APOE Ɛ4 carriers showed faster and slower decline, respectively, than noncarriers. PTSD in older adults is associated with accelerated decline in working memory. Men and/or APOE Ɛ4 carriers may be important targets for early cognitive decline prevention.