Assisted injection within supervised injection services : Uptake and client characteristics among people who require help injecting in a Canadian setting

Background: People who require help injecting illicit drugs experience elevated rates of a range of health-related harms, including overdose and acquisition of blood-borne pathogens. In response, some supervised injection services (SIS) in Canada have begun to permit clients to be physically injected by fellow clients or staff members. However, little is known about uptake and characteristics of clients who engage in this practice. We therefore sought to examine factors associated with receiving injection assistance at SIS among people who require help injecting drugs in Vancouver, Canada. Methods: Data were drawn from two community-recruited prospective cohort studies of people who inject drugs (PWID). We used multivariable generalized estimating equation (GEE) analyses with time-updated covariates to identify factors associated with self-reported receipt of injection assistance at SIS. Results: Between June 2017 and December 2018, 319 individuals who reported having recently required help injecting were included in the study. Of these, 160 (51.0%) were women and the median age was 42 years at baseline. In total, 54 (16.9%) participants reported receiving injection assistance at a SIS at least once over an average of 3.3 months of follow-up. In multivariable GEE analyses, recent homelessness (Adjusted Odds Ratio [AOR] = 2.04; 95% confidence interval [CI]: 1.13 – 3.66), fentanyl injection (AOR = 3.45; 95% CI: 1.42 – 8.41), non-fatal overdose (AOR = 1.86; 95% CI: 1.02 – 3.38) and enrolment in methadone maintenance therapy (AOR = 1.89; 95% CI: 1.03 – 3.47) were associated with increased odds of receiving injection assistance at SIS. Conclusion: Although uptake of assisted injection at SIS was relatively low among this sample of people who require help injecting, this practice was associated with several indicators of structural vulnerability and drug-related risk. These findings suggest that accommodating assisted injection within SIS may be providing opportunities to engage and reduce harms among higher-risk subpopulations of PWID in this setting.Medicine, Faculty ofNon UBCMedicine, Department ofReviewedFacultyResearcherPostdoctora