RESUMEN
BACKGROUND: Prescribing medication for opioid use disorder (MOUD) in primary care helps meet treatment demand, but few studies examine long-term treatment retention among medically-underserved primary care patients. METHODS: This 9-year retrospective study assessed overall retention at 6 months, and yearly up to 9 years, among 1451 patients with at least 6 months of buprenorphine prescription data from a federally-qualified health center (FQHC). We also examined whether patients who had gaps in treatment (>14 days without medication) later returned to care. Associations with treatment retention over total time in care were assessed. RESULTS: On average, patients received buprenorphine treatment for 2.26 years. Among patients who experienced gaps in treatment but returned to care within 90 days, 64% were still receiving buprenorphine at six months (n=930 of 1451), and 70% (n =118 of 169) at 9 years, with an average yearly interval retention of 69% (range: 58-74%). Patients were on MOUD treatment and not in a gap about 81% of the time, and averaged 1.0 gap per patient per year (SD: 1.09; range 0-7.87). The mean gap length over the treatment period was 33.16 days. Older age, higher percentages of negative opioid tests, negative cocaine tests, and positive buprenorphine tests, and having diabetes were associated with longer treatment retention. CONCLUSIONS: Opioid use disorder (OUD) can be treated successfully in primary care FQHCs. Treatment gaps are common and reflect the chronic relapsing nature of OUD.