B – 37 Exploring the Impact of Biological Sex and Combat Exposure on Neurobehavioral Symptom Reporting in Post-9/11 Veterans Screening Positive for Traumatic Brain Injury

Objective Previous studies have independently examined the effects of biological sex and combat exposure on neurobehavioral symptoms (NBS) following military traumatic brain injury (TBI). However, much of this literature has been hampered by small sample sizes, especially for female Veterans. The present study sought to examine the association between sex and combat exposure on NBS in a large, nationwide sample of post-9/11 Veterans. Method 2,065 Iraq/Afghanistan-era Veterans (age: M=42.8 years [SD=10.5]) who screened positive for TBI as part of the VA TBI Screening and Evaluation Program were evaluated. Combat exposure was assessed using the Combat Experiences Scale (CES) of the Deployment Risk and Resilience Inventory (DRRI). The DRRI-CES total score was dichotomized using a median split (Mdn=32) to derive high and low combat groups. Participants were then categorized into four groups: high-combat/male (n=1,612), high-combat/female (n=186), low-combat/male (n=207), and low-combat/female (n=60). NBS were assessed using the Neurobehavioral Symptom Inventory (NSI). Results ANCOVAs adjusting for age, race/ethnicity, and posttraumatic stress disorder (PTSD) status showed significant group differences on the NSI total score and several NBS summary indices (p’s = <.001 to .048). Pairwise comparisons revealed that the high-combat/male, high-combat/female, and low-combat/female groups endorsed comparable NBS to one another, but all three groups endorsed significantly greater symptoms relative to the low-combat/male group. Conclusion Male Veterans with high combat exposure as well as female Veterans with any type of combat exposure experienced the greatest rates of NBS, highlighting the importance of considering both biological sex and combat exposure history when assessing subjective symptoms following TBI.