10-year retention of a comprehensive treatment model of buprenorphine for opioid use disorder.

Background: There has been extensive research demonstrating the effectiveness of medications for opioid use disorder (MOUD) but limited investigation into its long-term retention rate.

Objective: Assess the long-term treatment retention of a buprenorphine-based MOUD clinic with additional stratifications by age and gender.

Methods: This retrospective study analyzed 10-years of data from a MOUD clinic in West Virginia that served 3,255 unique patients during the study period (2009-2019). Retention was measured by summation of total treatment days with a new episode of care defined as re-initiating buprenorphine treatment after 60+ consecutive days of nonattendance. Kaplan-Meier survival analysis, with the log-rank test, was used to compare retention by gender and age.

Results: The mean age was 38 (SD = 10.6) and 95% were non-Hispanic white. Irrespective of treatment episode, 56.8% of patients were retained ≥ 90 days, and the overall median time in treatment was 112 days. Considering only the first treatment episode, 48.4% of 3,255 patients were retained at least 90 days and the overall median was 77 days. Female patients had a ≥ 90 day retention rate of 52.2% for the first admission and 60.1% for multiple admissions, both significantly higher than those of male subjects (44.1% and 53.0%). Additionally, patients ≤ 24 years old had the lowest rate of treatment retention, while patients aged ≥ 35 had the highest.

Conclusions: This study adds to the limited data regarding long-term retention in MOUD. Our findings indicate gender and age were highly correlated with retention in MOUD treatment.