Longitudinal Factors Associated with Used Syringe Lending Among HIV-Positive Antiretroviral Therapy-Naïve People Who Inject Drugs in a Canadian Setting.

Sharing used syringes is an important route of HIV transmission, however, factors shaping used syringe-lending among antiretroviral therapy (ART)-naïve HIV-positive people who inject drugs (PWID) are not well-characterized. Multivariable logistic regression analyses using generalized estimating equations (GEE) were employed to investigate correlates of used syringe lending among ART-naïve PWID. Data was drawn from ACCESS, a prospective community-recruited cohort of HIV-positive illicit drug users in Vancouver, Canada, from 1996 to 2015. The analysis included 482 ART-naïve PWID, of which 116 (24.1%) reported ≥ 1 periods of used syringe lending. In longitudinal analyses, incarceration (Adjusted Odds Ratio [AOR] = 2.18, 95% Confidence Interval [CI] 1.48-3.20), daily cocaine injection (AOR= 1.97, 95% CI 1.33-2.90), and sex work (AOR = 1.61, 95% CI 1.02-2.55) during the 180-day observation period were positively associated with used syringe lending, while having a high school diploma (AOR = 0.63, 95% CI 0.43-0.93) and holding formal employment (AOR = 0.20, 95% CI 0.05-0.82) were negatively associated. We found a high prevalence of used syringe lending among ART-naïve HIV-positive PWID, particularly among those recently incarcerated, involved in sex work or who injected cocaine frequently. Conversely, markers of higher socio-economic status were negatively associated with used syringe lending. These findings highlight the critical need for policies and interventions to decrease socio-economic marginalization and criminalization among PWID living with HIV alongside the scale up of access to harm reduction services.