1Columbia University, Mailman School of Public Health, New York, New York, USA.
2Department of Medicine, University of California San Francisco, School of Medicine, San Francisco, California, USA.
3Department of Epidemiology and Biostatistics, University of California San Francisco, School of Medicine, San Francisco, California, USA.
4University of California, School of Medicine, Positive Health Program San Francisco General Hospital San Francisco, San Francisco, California, USA.
Female injection drug users (IDUs) may report differences in injection behaviours that put them at greater risk for hepatitis C virus (HCV). Few studies have examined these in association with HCV incidence.
Longitudinal data from a cohort of 417 HCV-uninfected IDU aged 30 or younger were analysed. Cox proportional hazards was used to model female sex as a predictor of new HCV infection. General estimating equation (GEE) analysis was used to model female sex as a predictor of HCV-associated risk behaviour prospectively.
Women were significantly more likely than men to become infected with HCV during study follow-up (HR 1.4, p<0.05), and were also more likely than men to report high-risk injecting behaviours, especially in the context of sexual and injecting relationships. Sex differences in injecting behaviours appeared to explain the relationship between sex and HCV infection.
Young women's riskier injection practices lead to their higher rates of HCV infection. Further study on the impact of intimate partnership on women's risk behaviour is warranted.