Association of Implementation of Postoverdose Outreach Programs With Subsequent Opioid Overdose Deaths Among Massachusetts Municipalities.

Nonfatal opioid overdose is the leading risk factor for subsequent fatal overdose and represents a critical opportunity to reduce future overdose and mortality. Postoverdose outreach programs emerged in Massachusetts beginning in 2013 with the main purpose of linking opioid overdose survivors to addiction treatment and harm reduction services. To evaluate whether the implementation of postoverdose outreach programs among Massachusetts municipalities was associated with lower opioid fatality rates compared with municipalities without postoverdose outreach programs. This retrospective interrupted time-series analysis was performed over 26 quarters (from January 1, 2013, through June 30, 2019) across 93 municipalities in Massachusetts. These 93 municipalities were selected based on a threshold of 30 or more opioid-related emergency medical services (EMS) responses in 2015. Data were analyzed from November 2021 to August 2022. The main exposure was municipality postoverdose outreach programs. Municipalities had various program inceptions during the study period. The primary outcome was quarterly municipal opioid fatality rate per 100 000 population. The secondary outcome was quarterly municipal opioid-related EMS response (ambulance trips) rates per 100 000 population. The mean (SD) population size across 93 municipalities was 47 622 (70 307), the mean (SD) proportion of female individuals was 51.5% (1.5%) and male individuals was 48.5% (1.5%), and the mean (SD) age proportions were 29.7% (4.0%) younger than 25 years, 26.0% (4.8%) aged 25 to 44 years, 14.8% (2.1%) aged 45 to 54 years, 13.4% (2.1%) aged 55 to 64 years, and 16.1% (4.4%) aged 65 years or older. Postoverdose programs were implemented in 58 municipalities (62%). Following implementation, there were no significant level changes in opioid fatality rate (adjusted rate ratio [aRR], 1.07; 95% CI, 0.96-1.19; P = .20). However, there was a significant slope decrease in opioid fatality rate (annualized aRR, 0.94; 95% CI, 0.90-0.98; P = .003) compared with the municipalities without the outreach programs. Similarly, there was a significant slope decrease in opioid-related EMS response rates (annualized aRR, 0.93; 95% CI, 0.89-0.98; P = .007). Several sensitivity analyses yielded similar findings. In this study, among Massachusetts municipalities with high numbers of opioid-related EMS responses, implementation of postoverdose outreach programs was significantly associated with lower opioid fatality rates over time compared with municipalities that did not implement such programs. Program components, including cross-sectoral partnerships, operational best practices, involvement of law enforcement, and related program costs, warrant further evaluation to enhance effectiveness.