Predictors of Opioid and Alcohol Pharmacotherapy Initiation at Hospital Discharge Among Patients Seen by an Inpatient Addiction Consult Service

Background: Medications for opioid use disorder (MOUD) and alcohol use disorder (MAUD) are effective and under-prescribed. Hospital-based addiction consult services can engage out-of-treatment adults in addictions care. Understanding which patients are most likely to initiate MOUD and MAUD can inform interventions and deepen understanding of hospitals' role in addressing substance use disorders (SUD). Objective: Determine patient- and consult-service level characteristics associated with MOUD/MAUD initiation during hospitalization. Methods: We analyzed data from a study of the Improving Addiction Care Team (IMPACT), an interprofessional hospital-based addiction consult service at an academic medical center. Researchers collected patient surveys and clinical data from September 2015 to May 2018. We used logistic regression to identify characteristics associated with medication initiation among participants with OUD, AUD, or both. Candidate variables included patient demographics, social determinants, and treatment-related factors. Results: Three hundred thirty-nine participants had moderate to severe OUD, AUD, or both and were not engaged in MOUD/MAUD care at admission. Past methadone maintenance treatment (aOR 2.07, 95%CI (1.17, 3.66)), homelessness (aOR 2.63, 95%CI (1.52, 4.53)), and partner substance use (aOR 2.05, 95%CI (1.12, 3.76) were associated with MOUD/MAUD initiation. Concurrent methamphetamine use disorder (aOR 0.32, 95%CI (0.18, 0.56)) was negatively associated with MOUD/MAUD initiation. Conclusions: The association of MOUD/MAUD initiation with homelessness and partner substance use suggests that hospitalization may be an opportunity to reach highly-vulnerable people, further underscoring the need to provide hospital-based addictions care as a health-system strategy. Methamphetamine's negative association with MOUD/MAUD warrants further study.