A-15 PTSD Symptoms Are Related to Cognition Following Complicated Mild and Moderate TBI, but Not Severe and Penetrating TBI

Abstract

Abstract Objective Despite the strong evidence suggesting post-traumatic stress disorder (PTSD) symptoms negatively impact cognition following mild traumatic brain injury (TBI), little is known about this relationship in more severe TBI. This study investigates the relationship between PTSD symptoms and cognitive performance following complicated mild, moderate, severe, and penetrating TBI. Methods Participants were 137 U.S. military service members and veterans (SMVs) with a history of complicated mild or more severe TBI prospectively enrolled in the Defense and Veterans Brain Injury Center (DVBIC)/Traumatic Brain Injury Center of Excellence (TBICoE) 15-Year Longitudinal TBI Study. Participants were divided into two groups: complicated mild/moderate TBI (n = 64) and severe/penetrating TBI (n = 73). Participants completed a neuropsychological assessment, including the PTSD Checklist-Civilian Version one year or more post-injury. Six neuropsychological composite scores and an overall test battery mean (OTBM) were considered. Participants who failed symptom validity tests were excluded. Hierarchical linear regressions were conducted evaluating neuropsychological performance. Results TBI severity (βs:-0.163 to −0.253, ps < 0.04) and PTSD symptoms (βs:-0.189 to −0.212), ps < 0.03) were related to neuropsychological performance in the overall sample. Within the severe/penetrating TBI group, PTSD symptoms were unrelated to cognitive performance. Within the complicated mild/moderate TBI group, PTSD symptoms were significantly related to processing speed (R2Δ = 0.080, β = −0.284, p = 0.016), immediate memory (R2Δ = 0.204, β = −0.453, p < 0.001), delayed memory (R2Δ = 0.180, β = −0.426, p < 0.001), executive functioning (R2Δ = 0.102, β = −0.319, p = 0.007), and the OTBM (R2Δ = 0.170, β = −0.413, p < 0.001). Discussion PTSD symptom severity was significantly related to neuropsychological performance in SMVs with complicated mild/moderate TBI. PTSD symptoms should be considered when evaluating patients with a history of complicated mild to moderate TBI.