Suicide within 1 year of non-fatal overdose: Risk factors and risk reduction with medications for opioid use disorder

Objective: Individuals with substance use disorders and overdoses have high risk of suicide death, but evidence is limited on the relationship between interventions following the initial overdose and subsequent suicide death. Methods: National Medicare data were used to identify Medicare disability beneficiaries (MDBs) with inpatient or emergency care for non-fatal opioid overdoses from 2008 to 2016. Data were linked with National Death Index (NDI) to obtain dates and causes of death for the sample. Cox proportional hazards models estimated the associations between exposure to interventions (mechanical ventilation, MOUD) and suicide death. Results: The sample (n = 81,654) had a suicide rate in the year following a non-fatal overdose of 566 per 100,000 person-years. Post-overdose MOUD was associated with an adjusted hazard ratio of 0.20 (95%CI: 0.05,0.85). Risk of suicide was elevated for those whose initial overdoses required mechanical ventilation as part of the treatment (aHR: 1.86, 95%CI:[1.48,2.34]). Conclusions: The year following a non-fatal opioid overdose is a very high-risk period for suicide among MDBs. Those receiving MOUD had an 80% reduction in the hazards of suicide, while those whose overdose treatment involved mechanical ventilation had 86% higher hazards of death by suicide. Our findings highlight the importance of psychiatric intervention in this high-risk population. Efforts are needed to initiate and retain more patients in MOUD.