Cognitive trajectory changes in African American veterans with combat PTSD

Abstract

AbstractBackgroundEpidemiological study shows that posttraumatic stress disorder (PTSD) has been linked to increased risk of Alzheimer’s disease (AD). However, longitudinal study of Holocaust survivors does not show accelerated cognitive decline in those with PTSD. We compared cross‐sectional and longitudinal cognitive function in a cohort of African American (AA) veterans with combat PTSD to that in a cohort of elderly AA males without PTSD to determine if PTSD was associated with a more rapid cognitive decline.MethodEighteen male AA Veterans with the combat PTSD who received treatment at the VA Puget Sound Health Care System in Seattle, participated in a longitudinal study of aging at UW ADRC between 2007‐16. Fifty‐four male AA subjects without PTSD were selected from the National Alzheimer’s Coordinating Center (NACC) dataset and matched by age (± 4 years), education (± 1 year), and MMSE score (± 2 points) as a comparison group (Table 1). Longitudinal data were available for 16 PTSD+ and 40 PTSD‐ participants. All participants were free of dementia or Mild Cognitive Impairment (MCI) and were assessed using the NACC Uniform Data Set version 2 (UDS 2.0) neuropsychological test battery. Linear mixed effects regression was used to estimate mean cognitive outcome at baseline and mean slope of change over follow‐up.ResultAs shown in the Figure 1, mean MMSE score at baseline and slope of change did not significantly differ between those with and without PTSD (p ≥ .35). The mean immediate and delayed recall scores from the Wechsler Memory Scale‐Revised Logical Memory were similar at baseline (p >.98) and showed no difference in change from baseline (p > .69). Similarly, there were no statistical differences in means at baseline or slope of change by group for Digit Span Forward and Backward, Category Fluency (animals and vegetables), WAIS‐R Digit Symbol test, and Trail Making Test (A and B) (all p‐values >.27).ConclusionCognitive function in AA veterans with combat PTSD was comparable to AA men without PTSD over an average of 4 years. These findings need to be replicated in a larger cohort with a longer duration of follow‐up.