Emergency Clinician Buprenorphine Initiation, Subsequent Prescriptions, and Continuous Prescriptions

Abstract

Importance: Rates of opioid use disorder (OUD) and associated mortality in the US remain high. Treatment of OUD with buprenorphine reduces morbidity and mortality. There have been national efforts to expand buprenorphine initiation to the emergency department (ED), where many patients with low treatment access seek medical care. Adoption and trends of emergency clinician buprenorphine prescribing are unknown.

Objective: To describe emergency clinician buprenorphine initiation for OUD, subsequent prescriptions, and changes over time in California.

Design, setting, and participants: Observational retrospective study of buprenorphine prescriptions in the California Controlled Substance Utilization Review and Evaluation System (CURES) database from January 1, 2017, to December 31, 2022. Any patient aged 18 to 79 years with a California zip code who filled a buprenorphine prescription in CURES and their California prescribers were eligible for inclusion.

Exposure: Buprenorphine prescription by an emergency clinician.

Main outcomes and measures: Outcomes included (1) the number of patients prescribed buprenorphine; (2) the number of clinicians prescribing buprenorphine; (3) the number and characteristics of buprenorphine prescriptions; (4) the percentage of emergency clinician buprenorphine initiation prescriptions with subsequent linkage to a second prescription and continuous prescriptions, also reported as a continuation ratio; and (5) days and number of initiation prescriptions prior to continuous prescriptions.

Results: In this retrospective observational study, 345 024 patients received 3.8 million buprenorphine prescriptions from 21 099 clinicians in California from 2017 to 2022. The mean age of patients at the time of first buprenorphine prescription was 37 years; 8187 (67%) were male. Emergency clinicians increased from 2% (n = 78) to 16% (n = 1789) of buprenorphine prescribers in 2017 and 2022, respectively (P < .001). Buprenorphine initiation prescriptions by emergency clinicians increased from 0.1% (n = 53) to 5% (n = 4493) of all initiation prescriptions in 2017 and 2022, respectively (P = .001). The continuation ratio for patients to receive a second prescription within 40 days of an ED initiation was 2.8 (10 823/3916). The continuation ratio for patients to start 180 days or more of continuous prescriptions within 40 days of ED buprenorphine initiation was 18.3 (10 823/593) and 9.1 within 1 year (5989/655 [2017-2021 data]).

Conclusions and relevance: These findings suggest increasing prescription of buprenorphine for OUD by California emergency clinicians from 2017 to 2022, with approximately 1 in 9 patients going on to receive continuous buprenorphine prescriptions within 1 year.

Figure 1.. Trends in Buprenorphine Prescriptions by Emergency Clinicians, California, 2017-2022

Panel A shows annual values for new and unique emergency clinicians prescribing buprenorphine and patients who received buprenorphine from emergency clinicians. Panel B shows the percentage of each emergency medicine subcategory of clinicians across all specialties in the California Controlled Substance Utilization Review and Evaluation System (CURES). The numerators and dominators for each point are in Table 1. A new prescriber or patient was defined as having no prior buprenorphine prescription in the CURES database from January 1, 2016, to date of first prescription. Unique prescribers and patients include all individuals for that year regardless of prescription history. A test for trend of all slopes in panel A was statistically significant for trend at P < .001. The graphs show that not only are overall numbers of emergency clinicians and patients receiving buprenorphine from emergency clinicians increasing, but these numbers are increasing relative to other specialties.

Figure 2.. Sankey Diagram of Emergency Clinician Buprenorphine Initiation, 2017-2021, to Subsequent Buprenorphine Prescriptions

The 5989 emergency clinician initiation prescriptions are depicted by the light purple bar on the left. Patients “flow” to the blue bar if they received a second prescription within 40 days of the initiation prescription (with shading and numbering indicating those whose second prescription was within 1-7, 8-14, 15-28, or 29-40 days) to the red bar if they did not achieve continuous treatment, or to the gray bar (non–emergency clinician) or orange bar (emergency clinician) if they did not achieve continuous treatment but received a second emergency clinician initiation prescription in 1 year or less. Patients “flow” to their third prescription or to the red/gray/orange bars in a similar manner. From the third prescription, patients either continued with buprenorphine for ≥180 days or did not continue and move to the red/gray/orange bars. The green bands indicate the proportion of individuals who achieved continuous treatment within 1 year of initiation prescription, with the darkest band representing individuals whose continuous treatment began within 40 days of the initiation prescription. Patients who received a second initiation prescription within 1 year of the first continue to the rightmost nodes. The paths between nodes demonstrate that shorter intervals between initial prescriptions (the linkage between emergency clinician and continuing care) were associated with achieving continuous treatment. Overall, 10.9% of patients who received an initiation prescription from an emergency clinician began ≥180 days of continuous prescriptions within 1 year (655/5989). The continuation ratio is 9.1 (5989/655). Numbers may not add to 100% because of rounding.