Trends in unintentional injury death among post-9/11 Army Veterans who do and do not use Veteran Health...

It is unknown if unintentional injury death rates vary among Army Veterans who do and do not use the Veterans Health Administration (VHA). We estimated, and compared by VHA-use group, age-adjusted average annual unintentional injury death rates and time-dependent hazard rates (HRs) after separation.

Data were from the Substance Use and Psychological Injury Combat Study, a longitudinal cohort of Army soldiers returning from an Afghanistan/Iraq deployment in FYs 2008-2014 using administrative data from the Military Health System, Veterans Health Administration and National Death Index. We selected soldiers who separated from active duty service by 9/30/2017 (n = 649,811). The exposure was time since separation, moderated by VHA-use group. The outcome was unintentional injury death (all, motor vehicle crash [MVC], overdose) through 2018.

The HR for all unintentional injury and MVC death for 0-2 years post-separation were higher for the no VHA-use group than the VHA-use group (e.g., MVC, year 0-1 HR: 75.1 (95% CI: 61.7, 88.4) vs. 16.4 (95% CI: 12.8, 20.0)). This changed to either no difference or higher risk for the VHA-use group as time since separation increased. For unintentional overdose, there was no difference in HRs between groups in 0-2 years post-separation; risk was higher for the VHA-use group for the remainder of follow-up (e.g., no VHA use, years 3-5 HR: 8.7 (95% CI: 5.1, 12.3) vs. 28.9 (95% CI: 25.2, 32.5) for VHA use group).

The risk for unintentional MVC and overdose death since separation differed based on use of VHA services among post-9/11 Veterans. Intervention strategies that address differences in time since separation and whether Veterans use the VHA or not may be required.