Risk of Adverse Outcomes Among Veterans Who Screen Positive for Traumatic Brain Injury in the Veterans Health Administration But Do Not Complete a Comprehensive Evaluation: A LIMBIC-CENC Study.

Abstract

To examine whether post-9/11 veterans who screened positive for mild traumatic brain injury (mTBI) but did not complete a Comprehensive TBI Evaluation (CTBIE) were at higher risk of subsequent adverse events compared with veterans who screened positive and completed a CTBIE. Upon CTBIE completion, information assessed by a trained TBI clinician indicates whether there is mTBI history (mTBI+) or not (mTBI-). Veterans Health Administration (VHA) outpatient services. A total of 52 700 post-9/11 veterans who screened positive for TBI were included. The follow-up review period was between fiscal years 2008 and 2019. The 3 groups studied based on CTBIE completion and mTBI status were: (1) mTBI+ (48.6%), (2) mTBI- (17.8%), and (3) no CTBIE (33.7%). This was a retrospective cohort study. Log binomial and Poisson regression models adjusting for demographic, military, pre-TBI screening health, and VHA covariates examined risk ratios of incident outcomes based on CTBIE completion and mTBI status. Incident substance use disorders (SUDs), alcohol use disorder (AUD), opioid use disorder (OUD), overdose, and homelessness documented in VHA administrative records, and mortality as documented in the National Death Index, 3 years post-TBI screen. VHA outpatient utilization was also examined. Compared with the no CTBIE group, the mTBI+ group had 1.28 to 1.31 times the risk of incident SUD, AUD, and overdose, but 0.73 times the risk of death 3 years following TBI screening. The mTBI- group had 0.70 times the risk of OUD compared with the no CTBIE group within the same period. The no CTBIE group also had the lowest VHA utilization. There were mixed findings on risk of adverse events for the no CTBIE group relative to the mTBI+ and mTBI- groups. Future research is needed to explore the observed differences, including health conditions and healthcare utilization, documented outside VHA among veterans who screen positive for TBI.