Identifying barriers to emergency department-initiated buprenorphine: A spatial analysis of treatment facility access in Michigan.

Study Objectives: Emergency department (ED)-initiated buprenorphine/naloxone has been shown to improve treatment retention and reduce illicit opioid use; however, its potential may be limited by a lack of accessible community-based facilities. This study compared one state's geographic distribution of EDs to outpatient treatment facilities that provide buprenorphine treatment and identified ED and geographic factors associated with treatment access.

Methods: Treatment facility data were obtained from the SAMHSA 2018 National Directory of Drug and Alcohol Abuse Treatment Facilities, and ED data were obtained from the Michigan College of Emergency Physician's 2018 ED directory. Geospatial analysis compared EDs to buprenorphine treatment facilities using 5-, 10-, and 20-mile network buffers.

Results: Among 131 non-exclusively pediatric EDs in Michigan, 57 (43.5%) had a buprenorphine treatment facility within 5 miles, and 66 (50.4%) had a facility within 10 miles. EDs within 10 miles of a Medicaid-accepting, outpatient buprenorphine treatment facility had higher average numbers of beds (41 vs. 15; p < 0.0001) and annual patient volumes (58,616 vs. 17,484; p < 0.0001) compared to those without. Among Michigan counties with EDs, those with at least one buprenorphine facility had larger average populations (286,957 vs. 44,757; p = 0.005) and higher annual rates of opioid overdose deaths (mean 18.3 vs. 13.0 per 100,000; p = 0.02) but were similar in terms of opioid-related hospitalizations and socioeconomic distress.

Conclusion: Only half of Michigan EDs are within 10 miles of a buprenorphine treatment facility. Given these limitations, expanding access to ED-initiated buprenorphine in states similar to Michigan may require developing alternative models of care.