B - 40 Sleep Mediates Anxiety and PTSD Symptoms in Service Members with a History of Mild Traumatic Brain Injury

Objective Depression, anxiety, and post-traumatic stress disorder (PTSD) are prevalent in individuals with a history of mild traumatic brain injury (mTBI). US military service members (SMs) are at increased risk of sleep deficiency, which may influence the relationship between mTBI and psychological outcomes. This analysis examines the interaction of sleep quantity and mTBI on symptoms of depression, anxiety, and PTSD. Method A sample of 177 non-treatment seeking SMs completed the Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI), and the Post Traumatic Stress Disorder Checklist (PCL-5) and reported the number of hours slept the prior night (“sleep quantity”). The sample included SMs with and without a self-reported history of mTBI. Hierarchical regressions on BDI, BAI, and PCL-5 total scores were computed with group and sleep quantity (model 1) and their interaction (model 2) as predictors and age as a covariate. Results The interaction of mTBI and sleep quantity on BAI (p = 0.019) and PCL-5 (p = 0.070) total scores was significant and marginally significant, respectively, wherein the negative association between sleep quantity and symptom reporting was stronger in the mTBI group than controls. No interaction between mTBI and sleep quantity was observed for BDI total score (p = 0.578). Conclusion Worse psychological symptoms in SMs with a history of mTBI is related to lower sleep quantity. It may benefit these SM to address sleep deficiency or other sleep problems to improve these symptoms. Improving sleep may provide a means of indirectly targeting the adverse psychological outcomes common among SMs with mTBI, particularly anxiety-related problems.