Hepatitis C virus infection in HIV-infected men in Singapore, 2006-2018: incidence and associated factors.

Background The epidemiology of hepatitis C virus (HCV) infection in people living with HIV has been evolving, with increasing evidence of permucosal (sexual) transmission identified predominantly in HIV-positive men who have sex with men (MSM). The aim of this study was to estimate the incidence rate and elucidate epidemiological factors associated with HCV infection among HIV-infected men in Singapore from 2006 to 2018.<bold>Methods: </bold>A retrospective cohort study was conducted using a clinical database maintained by the Clinical HIV Program at the National Centre for Infectious Diseases, Singapore. Factors associated with incident HCV infections were identified using Cox proportional hazards regression analyses.<bold>Results: </bold>Among 1348 HIV-infected male patients who were HCV seronegative at baseline, 64 (4.7%) subsequently tested positive for HCV, giving an incidence of 0.88 per 100 person-years of follow-up (PYFU) (95% confidence interval (CI) 0.69-1.13). The incidence rate of HCV seroconversion increased from 0.33 (95% CI 0.12-0.71) per 100 PYFU in 2010-2012 to 1.93 (95% CI 1.36-2.67) in 2016-2018. Independent factors associated with incident HCV infection were younger age groups at HIV diagnosis versus ≥45 years, HIV acquisition via MSM or via both sexual contact and intravenous drug use versus heterosexual transmission, HIV diagnosis in later periods versus 2006-2009, and recent syphilis acquisition.<bold>Conclusions: </bold>An increasing trend of incident HCV infection was seen in HIV-infected men, particularly for MSM. Preventive and behavioural interventions should be targeted at HIV-infected individuals engaged in high-risk sexual behaviour. [ABSTRACT FROM AUTHOR]