Drug treatment and support service utilization amidst the COVID-19 pandemic among people who inject drugs in Baltimore, Maryland: An interrupted time-series analysis, 2015–2022

Background: The COVID-19 pandemic prompted many structural and social changes including adaptations to drug treatment policies and provision (e.g., take-home methadone flexibilities and telehealth services), but their collective impact on drug treatment use among people who inject drugs in the US remains unclear. This study characterized trends in drug treatment and support service utilization before and during the pandemic among current and former people who inject drugs in Baltimore, Maryland. Methods: An interrupted time-series analysis was conducted using longitudinal survey data collected between December 2015 and November 2022 among 780 participants in the AIDS Linked to the IntraVenous Experience (ALIVE) study—a community-based cohort of adults who have injected drugs in Baltimore (n = 7036 semi-annual person-visits). Average marginal changes in service utilization were estimated following logistic regression with generalized estimating equations. Results: At participants’ first pre-pandemic visit, 46.8 % attended group counseling/support group services, 13.5 % were prescribed buprenorphine, and 38.8% were prescribed methadone. After the onset of the pandemic, there was an immediate reduction in attending group services (−13.4 % [95%CI = −17.8 %, −8.9 %]) and a change in the trajectory of attendance (difference in quarterly percentage point change [QPPC] comparing before vs. during the pandemic = −0.9 % [95 %CI = −1.6 %, −0.1 %]). In contrast, there was a small immediate increase in buprenorphine use (2.3 % [95 %CI = 0.1 %, 4.6 %]) and no change in its trajectory (QPPC difference = −0.1 % [95 %CI = −0.6 %, 0.3 %]) after the pandemic's onset. A declining trajectory in methadone use before the pandemic accelerated during the pandemic, but this change was not statistically significant (QPPC difference = −0.5 % [95 %CI = −1.2 %, 0.2 %]). When prescribed buprenorphine/methadone during the pandemic, 28.8 % reported engagement in telehealth services (50.0 % for buprenorphine; 16.7 % for methadone). Conclusion: There were pandemic-related disruptions in group-based support service utilization. Meanwhile, service adaptations may have blunted the pandemic's impact on buprenorphine and methadone treatment, suggesting adaptive systems have the potential to optimize treatment delivery. Nonetheless, the observed declines in methadone treatment uptake warrant investigation.