B – 27 Impact of Physical Activity on Clinical Outcomes in MVP-Enrolled Veterans Completing the VA’s TBI Screening and Evaluation Program

Objective Although the relationship between physical activity (PA) and clinical outcomes following traumatic brain injury (TBI) has been extensively evaluated in the civilian TBI literature, few studies have examined these relationships in the Veteran population. We evaluated whether PA moderates the relationship between TBI and clinical outcomes in post-9/11 Veterans. Method Participants included Veterans (n=6,506; 77% male) enrolled in the Million Veteran Program (MVP) and screened for possible deployment-related TBI via the TBI Screening and Evaluation Program. TBI groups were categorized as “Screen−” (n=4,581) or “Screen+” (n=1,925). PA was assessed using self-reported frequency of engagement in vigorous exercise on an MVP-survey and categorized as “None” (n=1,229); “Some” (n=1,899), or “Frequent” (n=3,378). Clinical outcomes included self-reported assessments of subjective cognition (MOS-Cog-R), PTSD symptoms (PCL-M), depression/anxiety symptoms (PHQ-4), and health-related quality of life (VR-12). Linear regressions, adjusting for sociodemographic factors, evaluated interactions between TBI and PA on all outcomes. Results Overall models were significant (p’s<.001, R2=0.22–0.36) for each outcome. There were significant main effects of TBI (p’s<.001) and PA (p’s=<.001-.002), and significant TBIxPA interactions (p’s=.001-.023) on all outcomes. Among both Screen+ and Screen- groups, a dose-response effect of PA frequency was observed, such that the None-PA group fared the worst, followed by the Some-PA group, and finally the Frequent-PA group; however, this pattern was more pronounced within the Screen+ group. Conclusion Findings suggest a buffering effect of PA on symptom severity in post-9/11 Veterans, particularly among those with probable TBI history. These results underscore the potential of PA as an accessible intervention to improve clinical outcomes.