Outcomes of a mobile medical unit for low-threshold buprenorphine access targeting opioid overdose hot spots in Chicago

Opioid overdoses in Chicago are unevenly distributed, affecting medically underserved neighborhoods most acutely. Innovations in reaching patients perceived to be hard-to-reach (e.g., unstably housed, marginalized), especially in these underserved neighborhoods, are urgently needed to combat the overdose crisis. This study characterizes the pilot year of a mobile medical unit partnership between a large urban academic center and a community-based harm reduction organization in Chicago.

This is a retrospective cohort study of all patients who were seen on a mobile medical unit focused on providing low-threshold buprenorphine and primary care in areas with high opioid overdose rates on Chicago's West Side. Treatment episodes were accrued between July 1, 2021, and June 30, 2022 in the first year of operation. The main outcomes were number of patients seen, demographic characteristics of patients, and reason(s) for visit over time.

The study saw 587 unique patients on the mobile medical unit between July 1, 2021, and June 30, 2022. Approximately 64.6 % were African American, and more than half lacked active insurance or could not confirm insurance status at the time of visit. The most common reason for initial visit was COVID-19 vaccination (42.4 %), and the most common reason for follow-up visit was buprenorphine treatment (51.0 %). Eleven patients initially presented for other health concerns and later returned to initiate buprenorphine.

The mobile medical unit successfully reached nearly 600 patients in traditionally medically underserved Chicago neighborhoods with the highest overdose rates. The mobile unit's integrated approach met a variety of health needs, including buprenorphine initiation, with a unique opportunity for postoverdose initiation. Several patients initiated buprenorphine after presenting for different health concerns, showing the potential of an integrated approach to build on past mobile outreach programs and reach people with opioid use disorder who are not yet ready to initiate treatment.