Associations of Post-Traumatic Stress Disorder and Objective Subtle Cognitive Difficulties in Cognitively Unimpaired Older Veterans.

Introduction: Psychiatric conditions such as post-traumatic stress disorder (PTSD) and depression have a two-fold increased dementia risk in Veterans. Prior work has shown that psychiatric factors can both impact cognitive functioning and be early symptoms associated with Alzheimer's disease (AD). Objectively defined subtle cognitive difficulties (Obj-SCD) has been associated with cognitive decline and AD biomarkers. However, Obj-SCD has not yet been investigated in the context of psychiatric disorders.

Methods: A total of 179 cognitively unimpaired Veterans (50-92 years old) underwent a comprehensive neuropsychological evaluation at VA San Diego and a retrospective medical record review. Chi-squared tests compared rates of psychiatric diagnoses in Veterans with and without Obj-SCD.

Results: About 21% of the sample was classified as Obj-SCD. Relative to cognitively unimpaired Veterans, Veterans classified as Obj-SCD had higher rates of PTSD, but not higher rates of other psychiatric conditions (e.g., depression). The PTSD findings appear to be driven by measures of cognitive efficiency.

Conclusion: Elevated rates of PTSD, but not other psychiatric conditions, were observed among Veterans with Obj-SCD. The prevalence and type of subtle cognitive difficulties associated with PTSD in older Veterans demonstrates a need, and informs potential targets, for intervention. Further work is needed to determine mechanisms of subtle cognitive difficulties in older Veterans with PTSD.