Effect of concussion and blast exposure on clinical symptoms following deployment of US military personnel

OBJECTIVES: Mild traumatic brain injury (mTBI), otherwise known as concussion, is a common battlefield injury. Past studies suggest a link between single and repetitive TBI and associated clinical symptoms, including sleep disturbance, headaches, and memory problems. We aimed to assess the impact of present and past concussion and blast exposure on mental health and post-concussive symptoms. METHODS: Following return from deployment we administered a 14-item questionnaire to 2,612 male U.S. Marines, mean age 23.8±0.1 years, from units which saw the greatest amount of combat during their deployments to Afghanistan. The questionnaire examined history of blast exposure, concussion, and mental health and post-concussive symptoms, for both current and previous deployments, where applicable. Injuries and symptoms were assessed as either present or absent, while the number of blast exposures and instances of concussion were quantified. Blast distance was assessed using the minimum blast exposure distance reported. RESULTS: 721 (27.5%) Marines reported concussion during current deployment and 732 (28.0%) prior to deployment. 2258 (86.4%) Marines reported exposure to blasts, with 2150 (82.3%) reporting blast exposure during current deployment and 668 (25.6%) during prior deployments. There was a higher incidence of all symptoms (memory problems, headaches, ringing in the ears, trouble sleeping, balance problems, irritability, light and noise sensitivity, trouble seeing, alertness, interpersonal distance, and emotional numbing) in Marines with current deployment concussion compared to those without, as well as in Marines who reported current deployment blast exposure compared to those who did not. CONCLUSIONS: Preliminary findings suggest that either a current concussion or a current blast exposure increases the risk of mental health and post-concussive symptoms in US military personnel, with concussion having a greater influence on the presence of post-deployment symptoms. Disclaimer: The opinions or assertions contained herein are the private views of the authors and are not to be construed as official or reflecting the views of the Department of the Navy or the Department of Defense. Disclosure: Dr. Wolde has nothing to disclose. Dr. Perry has nothing to disclose. Dr. Haran has nothing to disclose. Dr. Campbell has nothing to disclose. Dr. Creason has nothing to disclose. Dr. Sher has nothing to disclose. Dr. Stentz has nothing to disclose. Dr. Tsao holds stock and/or stock options in Biogen Idec and Illumina.