Characteristics and Outcomes of Hospitalized Psychiatric Inpatients Treated with Buprenorphine for Co-occurring OUD

Introduction Despite being the gold standard for long term treatment and mortality reduction, medications for opioid use disorder (mOUD) are under utilized despite ongoing efforts to reduce barriers to access, with only 18% of qualifying patients undergoing treatment. Approximately 38% of patients nationally with an opioid use disorder (OUD) have a co-occurring psychiatric diagnosis; however, treatment for these co-occurring illnesses frequently do not occur simultaneously, especially among acutely psychiatrically ill patients. Inpatient psychiatric units often do not initiate patients on mOUD, such as buprenorphine, possibly due to lack of national policy encouraging expanded access. This study involves a pilot mOUD consultation service for patients admitted to inpatient psychiatric units, and aimed to characterize the patients involved, and compare certain variables (such as length of stay (LOS)) to inpatients without an OUD. Methods This IRB-approved retrospective single-site (level 1 trauma in academic hospital just outside New York City) study examined the medical records of patients who received consultations from our service between January 1st 2018 and August 15th 2020. Demographic and clinical information was collected and analyzed for descriptive statistics. There were no interventions; the primary outcome gathered was average length of stay for patients consulted. Results 123 patients received consultations during this time period. Patients had an average age of 37 years, identified predominantly as male, and were mostly White. About one third of the population was undomiciled, and almost three quarters were unemployed. Over half of the patients had prior treatment with buprenorphine. The most common primary psychiatric diagnosis was depression (over 50%), followed by bipolar disorders and schizophrenia spectrum illness. About 40% of patients had co-occurring stimulant use, followed by about 30% with marijuana use, and 16% with benzodiazepine use. The average LOS among patients treated with mOUD was not significantly longer than the average LOS for the inpatient units overall. Over half of the patients were established with outpatient or inpatient substance use treatment following discharge from psychiatry. Conclusions Our data supports initiating patients with co-occurring OUD and psychiatric illness on mOUD, regardless of severity of acute psychiatric symptoms. Our study did not find that initiating substance use treatment prolonged LOS. Initiating treatment on the psychiatric unit may have increased engagement in outpatient addiction services. Further studies are required to characterize potential benefits. Funding No Funding