Buprenorphine utilization among all Washington State residents' based upon prescription monitoring program data - Characteristics associated with two measures of retention and patterns of care over time

Abstract

BackgroundOpioid use disorder is a serious health condition for which buprenorphine is proven effective, yet providers substantially underutilize buprenorphine. We present two approaches to measuring treatment duration, factors associated with retention, and patterns of care. MethodsThe study determined incident buprenorphine prescribing for all Washingtonians utilizing prescription monitoring program data from 2012 to 2019. The study calculated episode of care and cumulative time in care. Generalized linear models estimated associations among the length of the first episode of care and cumulative time in care with sex, age, and rurality. Cox proportional hazards models estimated the time to discontinuing buprenorphine for the first four episodes of care and time to discontinuing the last episode of care. ResultsMean and median duration of the first episode were 320 and 84 days, respectively, and for cumulative time in care 308 and 195 days. A minority of peoples' first episodes exceeded 180 days (37%). Being female and older were significantly associated with longer first episodes and cumulative time in care. Survival analyses indicated that the proportion of those still in care at 6, 12, and 24 months into their first episode of care declined for those with more than one episode of care; conversely the study found much smaller differences in retention for the last episode of care, indicating that many people were eventually able to be retained in care for longer periods of time. ConclusionEpisodes of care and cumulative time on buprenorphine were both short compared to minimum quality recommendations of 180 days. Median cumulative time in care was double that of the first episode, highlighting that many people engage in subsequent episodes of substantial length. Episode of care and cumulative care analyses should inform states, payers, health care systems and providers in measuring and setting treatment duration goals.