B - 30 Influence of Military Blast Exposure on Subjective Post-Concussion Symptom Reporting

Abstract Objective Repeated subconcussive blast exposure associated with explosive breaching, mortars, and shoulder-fired artillery weapons is commonly seen in the military/veteran population and has been found to contribute to adverse neurological outcomes; however, the extent is not fully understood. The aim of this study was to assess the effects of blast exposure during military or other training exercises on neurobehavioral symptom endorsement. Method Cross-sectional data from 48 nonclinical post-deployment Operation Enduring Freedom/Operation Iraqi Freedom veterans prospectively-recruited for a study examining posttraumatic stress and cognitive correlates at an urban VA Medical Center were examined (M age = 36.02; SD = 6.12; M years of education = 14.94; SD = 1.84). The sample was 96% male, 41% White, 39% Black, 4% Asian, and 16% Other. The Neurobehavioral Symptom Inventory (NSI) was used to assess self-reported vestibular, somatosensory, cognitive, and affective post-concussion symptoms, and the Boston Assessment of Traumatic Brain Injury-Lifetime semi-structured clinical interview assessed military-related blast exposure. Results There was a significant difference in neurobehavioral symptoms based on blast exposure, F(4,43) = 3.49, p = 0.015; Wilk’s Λ = 0.755, partial η2 = 0.25. Follow-up analyses showed that veterans with history of blast exposure endorsed significantly higher levels of somatosensory (F(1,47) = 7.69, p = 0.008, η2 = 0.143); affective (F(1,47) = 12.66, p < 0.001, η2 = 0.216); cognitive (F(1,47) = 5.97, p = 0.018, η2 = 0.115); and vestibular (F(1,47) = 7.21, p = 0.010, η2 = 0.136) post-concussive symptoms on the NSI compared to those without history of military blast exposure. Conclusion Veterans with blast exposure during military service reported significantly greater levels of post-concussion symptoms. This demonstrates the need to assess history of blast exposure, implement prevention measures through safeguards and decreased exposure when possible, and establish treatment modalities to improve outcomes.