A systematic review of macro-, meso, and micro-level harm reduction interventions addressing the U.S. opioid overdose...

This systematic review aimed to 1) identify the range of opioid harm reduction interventions implemented at macro-, meso-, and micro-levels in the United States, and 2) summarize the outcomes of these interventions.

We conducted a systematic review of academic literature published between 2011-2023 following PRISMA guidelines. Articles were excluded if they reported on research that was not specific to opioids, did not report the effects of an intervention, or focused on a medical treatment for opioid use disorder. Two coders independently extracted data and reconciled discrepancies prior to narrative synthesis.

Of 6,198 articles initially identified, 36 met inclusion criteria across macro (n=7), meso (n=8), and micro (n=21) domains. Positive evidence for micro- and meso-level interventions is largely consistent, whereas evidence for macro-level interventions is mixed. Among micro- and meso-level interventions, supply distribution interventions were most effective in increasing safe use knowledge and behaviors among people who use drugs.

Most harm reduction interventions demonstrate moderate to strong evidence of effectiveness for addressing the opioid overdose epidemic across domains. Findings revealed a lack of multi-level interventions and a lack of culturally relevant interventions that prioritize Black and Brown communities disproportionately impacted during the opioid overdose epidemic's latter phases.