Supervised Injection Facilities as Harm Reduction: A Systematic Review

Context: Supervised injection facilities are harm reduction interventions that allow people who inject drugs to use previously obtained substances under the supervision of health professionals. Although currently considered illegal under U.S. federal law, several U.S. cities are considering implementing supervised injection facilities anyway as a response to the escalating overdose crisis. The objective of this review is to determine the effectiveness of supervised injection facilities, compared with that of control conditions, for harm reduction and community outcomes.

Evidence acquisition: Studies were identified from 2 sources: a high-quality, broader review examining supervised injection facility-induced benefits and harms (from database inception to January 2014) and an updated search using the same search strategy (January 2014‒September 2019). Systematic review methods developed by the Guide to Community Preventive Services were used (screening and analysis, September 2019‒December 2020).

Evidence synthesis: A total of 22 studies were included in this review: 16 focused on 1 supervised injection facility in Vancouver, Canada. Quantitative synthesis was not conducted given inconsistent outcome measurement across the studies. Supervised injection facilities in the included studies (n=number of studies per outcome category) were mostly associated with significant reductions in opioid overdose morbidity and mortality (n=5), significant improvements in injection behaviors and harm reduction (n=7), significant improvements in access to addiction treatment programs (n=7), and no increase or reductions in crime and public nuisance (n=7).

Conclusions: For people who inject drugs, supervised injection facilities may reduce the risk of overdose morbidity and mortality and improve access to care while not increasing crime or public nuisance to the surrounding community.