Engagement in substance use disorder treatment after an emergency department visit among persons at high risk of opioid overdose: A prediction analysis.

Background: Certified peer recovery specialists (CPRS) and licensed clinical social workers (LCSWs) can facilitate substance use disorder (SUD) treatment engagement for emergency department (ED) patients at risk for overdose. Predictors of treatment engagement after such behavioral services are unknown. Methods: This secondary analysis included Rhode Island ED patients at high risk for opioid overdose participating in a randomized controlled trial comparing the effectiveness of CPRS and LCSWs services (2018-2021). SUD treatment engagement within 90 days post-discharge was identified using statewide administrative data. Potential predictors were obtained from baseline questionnaires. Classification and regression trees (CART) were used to identify predictors of treatment engagement. Results: In the ED, 323 and 325 participants received CPRS and LCSWs services, respectively, among whom 141 (43.7 %) and 137 (42.2 %) engaged in SUD treatment within 90 days post-discharge. For the CPRS group, predictors of treatment engagement included unhealthy alcohol use, prescription opioid or benzodiazepine use in past 6 months, and lifetime history of: unstable housing, barriers to treatment, bipolar disorder diagnosis, addiction treatment, and recovery services. In the LCSW group, predictors included health insurance, current pain, opioid overdose in past year, and lifetime history of anxiety disorder diagnosis and mental illness treatment. However, CART had low predictive accuracy (CPRS: 60.9 %, LCSW: 54.8 %). Conclusions: Among ED patients at high risk of opioid overdose receiving behavioral services, 90-day SUD treatment engagement was high. Sociobehavioral and clinical patient characteristics did not accurately predict treatment engagement. Behavioral services should be offered to all ED patients at high risk of opioid overdose.