Symptom complaints following reports of blast versus non-blast mild TBI: does mechanism of injury matter?

Patients with a reported history of mild traumatic brain injury (mild TBI) due to blast (n = 298) or non-blast (n = 92) mechanisms were asked to complete the Neurobehavioral Symptom Inventory (NSI) and the Post-traumatic Stress Disorder Checklist (PCL). Mechanism of injury did not account for a significant amount of variance in post-concussion symptom reporting overall, nor did severity of mild TBI (i.e., brief loss of consciousness versus only an alteration of consciousness). Symptom reporting was greater in those injured more than 1 month ago compared to those injured less than 1 month ago and in those reporting higher levels versus lower levels of PTSD symptoms. When examining specific symptoms, the only symptom that significantly varied between groups was hearing difficulty (with the blast-injured group reporting more severe difficulty with hearing). Findings suggest that greater symptom reporting is most strongly related to emotional distress.