Interpersonal and structural factors associated with receptive syringe-sharing among a prospective cohort of female sex workers who inject drugs.

Abstract

To determine the interpersonal and structural factors associated with receptive syringe sharing (RSS) among female sex workers who inject drugs (FSW-IDU), a group at high risk of HIV/hepatitis C virus (HCV) acquisition. Sex workers And Police Promoting Health In Risky Environments (SAPPHIRE) study, a prospective cohort study. Baltimore, MD, USA PARTICIPANTS: One hundred and eighty FSW-IDU; mean age = 33 years, 77.1% white and 62.9% in a relationship/married. Surveys were conducted between April 2016 and February 2018. The main outcome was recent RSS (past 3 months). In addition to socio-demographic characteristics and drug use behaviors, we assessed factors at the interpersonal level, including injection practices, intimate partner and client drug use and exposure to violence. Structural-level factors included methods of syringe access. Nearly all FSW-IDU used heroin (97.1%) or crack cocaine (89.7%). Recent RSS was reported by 18.3%. Syringes were accessed from needle exchange programs (64.6%), pharmacies (29.7%), street sellers (30.3%) or personal networks (29.1%). Some FSW-IDU had clients or intimate partners who injected drugs (26.3 and 26.9%, respectively). Longitudinal factors independently associated with RSS in the multi-level mixed-effects model were recent client violence [adjusted odds ratio (aOR) = 2.17, 95% confidence interval (CI) = 1.09-4.33], having an intimate partner who injected drugs (aOR = 2.18, 95% CI = 0.98-4.85), being injected by others (aOR = 4.95, 95% CI = 2.42-10.10) and obtaining syringes from a street seller (aOR = 1.88, 95% CI = 0.94-3.78) or from a member of their personal network (aOR = 4.43, 95% CI = 2.21-8.90). Client violence, intimate partner injection drug use, being injected by others and obtaining syringes from personal connections appear to increase parenteral HIV/HCV risk among female sex workers who inject drugs.