Lifetime opioid overdose reported by 55% of pregnant individuals with OUD in buprenorphine treatment study

BACKGROUND: Opioid use disorder (OUD) during pregnancy is a leading contributor to peripartum morbidity and mortality, with overdose deaths rising significantly in recent years. Despite the identification of various factors associated with overdose events, including social, demographic, psychiatric, and neonatal outcomes, the relative contributions of these factors to peripartum overdose history (or lack thereof) remain unclear. Thus, this study aims to characterize factors associated with lifetime opioid-involved overdose events among currently pregnant individuals receiving buprenorphine (BUP) treatment for OUD. METHODS: Treatment-seeking pregnant individuals with an estimated gestational age of 6 to 30 weeks were enrolled in a large multisite randomized controlled trial evaluating 2 BUP formulations for OUD. Participant baseline demographic, substance use, and mental health data were collected using validated measures, and random forest modeling identified key factors associated with lifetime opioid overdose events. RESULTS: The 140 pregnant participants ( = 31.2 years, SD = 4.7; 87.1% White) reported an average of 8.7 years (SD = 5.8) of opioid use, with 92.1% endorsing lifetime prescription opioid use and 82.9% reporting heroin use. The average lifetime number of nonfatal opioid overdose events was 4.8 (SD = 12.1); an overdose was reported by 55% of the sample (n = 77). Random forest analysis (area under the receiver operating characteristic curve = 0.797) incorporating sociodemographic, substance use, and mental health characteristics found that the most important factors associated with lifetime overdose events were, in order, lifetime heroin use, trauma exposure, reliance on partners or parents for financial support, depressive symptoms, and lifetime cocaine use. CONCLUSIONS: These findings underscore the critical need to address substance use, co-occurring mental health, and socioeconomic challenges that are associated with previous opioid overdose. Identifying and targeting key modifiable overdose risk factors can inform the development of tailored interventions to improve outcomes for this population.