To combat serious adverse events (SAE) and suicide among veterans with opioid use disorder (OUD), the Veterans Health Administration (VHA) implemented the Stratification Tool for Opioid Risk Mitigation (STORM) in all VHA facilities. Patients identified as high-risk for SAE by STORM received a mandatory case review. This study focuses on high-risk patients with a new OUD diagnosis. Mandatory case review increased the odds of all-cause mortality, but not SAE. Patients whose opioids were discontinued after case review showed even higher odds of mortality.