Systematic review and meta-analysis to estimate the burden of fatal and non-fatal overdose among people who inject drugs

BackgroundPeople who inject drugs (PWID) have high overdose risk. To assess the burden of drug overdose among PWID in light of opioid epidemic-associated increases in injection drug use (IDU), we estimated rates of non-fatal and fatal overdose among PWID living in Organization for Economic Cooperation and Development (OECD) countries using data from 2010 or later. MethodsPubMed, Psych Info, and Embase databases were systematically searched to identify peer-reviewed studies reporting prevalence or rates of recent (past 12 months) fatal or non-fatal overdose events among PWID in OECD countries. Data were extracted and meta-analyzed using random effects models to produce pooled non-fatal and fatal overdose rates. Results57 of 13,307 identified reports were included in the review, with 33/57 studies contributing unique data and included in the meta-analysis. Other (24/57) studies presented overlapping data to those included in meta-analysis. The rates of non-fatal and fatal overdose among PWID in OECD countries were 24.74 per 100 person years (PY) (95% CI: 19.86 - 30.83; n=28; I2=98.5%) and 0.61 per 100 PY (95% CI: 0.32 - 1.16; n=8; I2=93.4%), respectively. The rate of non-fatal overdose was 27.79 in North American countries, 25.71 in Canada, 28.59 in the U.S., and 21.44 in Australia. ConclusionThese findings suggest there is a fatal overdose for every 40 non-fatal overdose events among PWID in OECD countries. The magnitude of overdose burden estimated here underscores the need for expansion of overdose prevention and treatment programs and serves as a baseline estimate for monitoring success of such programs.