The Mobile Overdose Response Program: A mobile, low-threshold opioid use disorder treatment model in Philadelphia

Low-threshold substance use treatment programs may help overcome barriers for marginalized individuals. The aims of this study were to 1) describe participant characteristics and treatment outcomes for a multi-site, Philadelphia-based mobile program providing street-based buprenorphine initiation, stabilization, and referral to ongoing care and 2) examine associations between patient characteristics and successful linkage.

We conducted a retrospective cohort study of patients receiving buprenorphine through Prevention Point Philadelphia's mobile overdose response program from 9/2020-12/2021. We abstracted electronic medical record data, including patient characteristics, mobile program treatment, and care linkage. We used descriptive statistics to characterize the sample and assessed the association between patient characteristics and successful care linkage using multi-variable logistic regression.

Two hundred thirty-seven patients initiated buprenorphine in the program across six sites. Mean age was 46. Participants were majority men (67 %); 59 % identified as Black, 33 % identified as White, and 15 % reported Hispanic ethnicity. Most were publicly insured (74 %) and 30 % were unstably housed. Basedline engagement in primary care (32 %), psychiatric treatment (5 %), and counseling (2 %) were low. Most participants reported heroin or fentanyl use at intake (87 %), with high rates of IV drug use (37 %)., and co-occurring substance use and prior buprenorphine treatment experience were common.. 86 % completed ≥1 mobile follow-up visit, and 69 % completed ≥4 mobile program visits. 51 % of patients attended at least one visit at an outside site, and 30 % had ≥2 visits for buprenorphine prescriptions at an outside site. 35 % of the referrals were internal, meaning they went to University-based practices staffed by the mobile unit physicians. In a multivariable logistic regression model, internal referral was associated with significantly increased odds of effective care linkage (aOR 2.47, 95 % CI 1.20-5.09).

Targeted community outreach with low-threshold substance use care facilitated treatment access among marginalized individuals. Participants showed high levels of engagement with the mobile program, but rates of outside care linkage, while comparable to retention in other low-threshold models, were lower. The only predictor of effective care linkage was referral to brick-and-mortar clinics staffed by mobile unit physicians. These findings support the importance of outreach beyond traditional health care settings to engage high-risk patients with OUD.