Number of Concussions Does Not Affect Treatment Response to Cognitive Rehabilitation Interventions Following Mild TBI in Military Service Members

Abstract Objective The study objective was to determine whether number of concussions would affect symptom improvement following cognitive rehabilitation (CR) interventions. Method Service members (N = 126) with concussion history completed a 6-week randomized control trial of CR interventions. Participants were stratified based on self-reported lifetime concussion frequency. Outcome measures included the Paced Auditory Serial Addition Test (PASAT), the Global Severity Index (GSI) from the Symptom Checklist-90-Revised, and the Key Behaviors Change Inventory (KBCI). Results Mixed-model analyses of variance revealed a significant main effect for time on cognitive, psychological, and neurobehavioral functioning. A significant main effect for the number of concussions was observed for GSI and KBCI, but not PASAT. Interactions between the number of concussions and time were not significant for any of the outcome variables. Conclusions Over the 6-week interval, improvements were found for all participants across all outcome measures. Number of concussions did not affect improvements over time.