HIV and Hepatitis C Virus Infection and Risk Behaviors Among Heterosexual, Bisexual, and Lesbian Women Who Inject Drugs in Australia.

PURPOSE: Women who inject drugs (WWID) are vulnerable to a range of harms, including exposure to sexually transmitted and blood-borne infections, abusive relationships, physical and sexual violence and mental health issues. Lesbians and bisexual women are at greater risk than heterosexual women for substance use disorders. This study aimed to compare a large sample of heterosexual, bisexual, and lesbian WWID and to identify correlates of sexual orientation.

METHODS: The Australian Needle and Syringe Program (NSP) Survey is an annual cross-sectional survey. People who inject drugs (PWID) who attend NSP services are invited to complete a brief self-administered questionnaire and provide a capillary dried blood spot. Of 22,791 survey respondents between 2004-2013, one third were women (n=7,604). Analyses were restricted to the first participation record for each respondent.

RESULTS: Of the 5,378 individual women, 4,073 (76%) identified as heterosexual, 1,007 (19%) identified as bisexual, and 298 (6%) identified as lesbian. HIV prevalence was low (<1.0%). More than half (56%) had been exposed to hepatitis C virus (HCV), with prevalence highest among bisexual women (59%). In adjusted analysis, bisexual women had significantly greater odds of initiating injection at a younger age (AOR 1.44, 95% CI 1.19-1.73), and reporting public injection (AOR 1.44, 95% CI 1.21-1.73) and receptive sharing of drug preparation equipment (AOR 1.20, 95% CI 1.00-1.44). Bisexual women (AOR 1.42, 95% CI 1.07-1.88) and lesbians (AOR 1.63, 95% CI 1.10-2.44) had significantly greater odds of reporting sex work than their heterosexual counterparts.

CONCLUSION: Results contribute to the literature on HIV and HCV transmission risk among WWID. Analysis of the relationship between sexual orientation and risk behavior identified bisexual orientation as independently associated with increased risk. Services that target PWID need to recognise and address a broad range of sexual identities and behaviors. Future research should explore reasons for increased risk in sexual minority women.