Needling Policy Makers and Sharpening the Debate: Do Syringe Exchange Programs Improve Health at the Population Level?

Context: In the midst of the current opioid epidemic, states have selected differing legislative routes implementing pathways to ensure access to clean needles and syringes. Objective: To determine whether states that implemented laws supporting syringe exchange programs (SEPs) had reductions in transmission rates of hepatitis B, hepatitis C, and HIV infection compared with states without such laws. Design and Setting: Utilizing a longitudinal panel design, we determined the legal status of SEPs in each state for years 1983-2016. Disease transmission rates for this period were estimated via a simple Poisson regression, with transmitted cases as the dependent variable, law categories as the predictor variables, and the log of state population as the exposure. The mean number of incident cases per state-year was also calculated. Participants: US states were utilized as the unit of analysis. Results: Hepatitis B and hepatitis C mean transmission rate per 100 000 population declined in states with local ordinances/decriminalized statutes and legalized SEPs (hepatitis B: 71% and 81%, respectively, differences P < .001; hepatitis C: 8% and 38%, respectively, differences P < .001). Reductions in mean incident cases per state-year mirrored these findings. HIV infection among injection drug users yielded inconsistent results. Conclusions: Hepatitis B and hepatitis C transmission were reduced at the population level in states with SEP laws in a pattern reflecting the degree of legal intervention. HIV infection, based upon a smaller data set, showed a mixed impact.