Systematic Review and Meta-Analysis to Estimate the Burden of Non-Fatal and Fatal Overdose Among People Who Inject...

People who inject drugs (PWID) have high risk for overdose, but there are no current estimates of overdose rates in this population. We aimed to estimate rates of non-fatal and fatal overdose among PWID living in the United States (US) and comparator countries (Canada, Mexico, United Kingdom, Australia), and ratios of non-fatal to fatal overdose rates, using literature published 01/01/2010 - 09/29/2023.

PubMed, PsycINFO, Embase, and ProQuest databases were systematically searched to identify publications reporting prevalence or rates of recent non-fatal and fatal overdose among PWID. Non-fatal and fatal overdose rates were meta-analyzed using random effects models. Risk of bias was assessed using a quality assessment tool, and heterogeneity was explored using sensitivity analyses.

Our review included 143 studies, with 58 contributing unique data to the meta-analysis. Non-fatal and fatal overdose rates among PWID in the US were 32.9 per 100 person-years (PY) (95% CI: 26.4-40.9) and 1.7 per 100 PY (95% CI: 0.9-3.2), respectively. Post-2016 data yielded a non-fatal overdose rate of 41.0 per 100 PY (95% CI: 32.1-52.5) and a fatal overdose rate of 2.5 per 100 PY (95% CI: 1.4-4.3) in the US. An estimated 5% of overdoses among PWID in the US and Canada resulted in death during 2010-2023, compared to 6% in the UK and 2% in Australia.

Findings demonstrate substantial burden of non-fatal and fatal overdose among PWID in the US and some comparator countries. Scale-up of interventions to prevent overdose mortality are urgently needed.