Concurrent impact of PTSD symptoms and alcohol use on working memory and executive functioning in a U.S. adult sample

Despite high comorbidity between posttraumatic stress disorder (PTSD) and alcohol use disorder (AUD) and well-documented independent impacts of each condition on cognitive functioning, few studies have explored the concurrent effects of PTSD and AUD on cognitive control. Recent intervention studies have explored working memory (WM) and executive functioning (EF) as potential treatment targets to improve outcomes for both PTSD and AUD, but there is a need to elucidate concurrent impacts of each condition to inform intervention development. The present study examined WM and EF performance in a sample of U.S. adults in relation to current PTSD symptom and alcohol use (AU) severity. We hypothesized that there would be main effects of both PTSD symptoms and AU severity on WM and EF outcomes, with an exploration of interaction effects. A sample of 112 participants (79% white, 61% female) recruited from a larger survey study also completed follow-up WM and EF tasks. Results did not support our hypotheses regarding main effects of PTSD and AU severity on WM and EF outcomes. Significant age effects were observed on WM measures such that higher age was associated with reduced performance. An interaction effect was detected for one EF measure (decision-making), such that decision-making performances were relatively stable at low to subthreshold PTSD symptoms regardless of AU severity but declined with increasing AU at clinically elevated PTSD symptoms. Findings reflect new information regarding the impact of concurrent PTSD and AU severity on EF, and implications for future research and intervention development are discussed.