Predictors of engagement and retention in care at a low-threshold substance use disorder bridge clinic

People with substance user disorder (SUD) have frequent intersections with the health care system; however, engagement and retention in SUD care remain low, particularly for marginalized populations. Low-threshold treatment models that aim to eliminate barriers to care are one proposed intervention to increase access and equity in SUD treatment.

This is a retrospective, cohort study of patients treated at a low-threshold bridge clinic from 2016 to 2021. The study's primary aim was to describe patient characteristics associated with engagement, defined as two or more completed visits, and treatment retention at 60 days, defined as a completed visit 45-to-75 days after first visit. A secondary outcome was transfer to ongoing treatment after bridge clinic. The study analyzed multivariable models assessing demographic and clinical predictors for each outcome using generalized estimating equations.

The study found that 1857 patients completed 2730 care episodes. The mean age was 38.7 years old, 70 % were male, 30 % female, 79 % White, 7 % Black, 9 % Latinx, and 97 % spoke English. Opioid use disorder (OUD) was the most common type of SUD, seen among 84 % of episodes, followed by alcohol (30 %), and stimulant use disorder (28 %). Seventy percent of bridge clinic episodes of care resulted in engagement, 38 % were retained at 60 days, and 28 % had transfer to care documented. In adjusted analyses, engagement was lower for Black patients compared to White patients and higher for patients who received buprenorphine or naltrexone. Retention for Black patients was also lower compared to White patients and higher for patients who were unhoused and patients who received buprenorphine or naltrexone. Transfer of care was more likely among patients who received buprenorphine.

At a low-threshold bridge clinic 70 % of patients successfully engaged in care and 38 % were retained at two months. While OUD and AUD were most prevalent, stimulant use was common in this population. Patients who received buprenorphine or naltrexone had higher engagement, and retention, and those receiving buprenorphine also had higher care transfer. Black patients had lower rates of engagement and retention. Treatment providers need to adopt low-threshold SUD care models to eliminate racial disparities and address the needs of people using stimulants.