Incident HCV Infections in the Swiss HIV Cohort Study: Natural History and Treatment Outcomes

Background: We recently observed dramatic changes in the hepatitis C virus (HCV) infection epidemic in the Swiss HIV Cohort Study (SHCS), including an 18-fold incidence increase in men who have sex with men (MSM). The long-term trends in outcomes of incident HCV infections are largely unknown. We studied the natural history, treatment uptake and outcomes of incident HCV infections between 1991 and 2012 in a nationwide cohort. Methodology: We included all patients followed in Swiss tertiary care hospitals with a documented HCV-seroconversion. Detailed information on HCV diagnosis, treatment and outcomes, as well as reasons for not starting HCV treatment was retrieved from the SHCS database and chart review using standardized case report forms. Natural history, treatment uptake and outcomes were compared between risk groups and time periods before and after the first description of the surging HCV epidemic in MSM in 2006 using Fisher’s exact test. Results: Of 121 HCV seroconversions, 2 were excluded due to insufficient information. Among the remaining 119 cases, 46 were MSM, 52 injection drug users, 17 heterosexuals and 4 from other HIV transmission risk groups. The proportion of MSM among patients with incident HCV infections increased from 20% before to 75% after 2006 (p<0.001). Fourteen patients died during follow-up, including 3 liver-related deaths. A spontaneous clearance was observed in 30% of cases. Fibroscan results were available for 45 (38%) individuals. The median liver stiffness was 5.9 kPa (IQR 4.6-7.4) after a median follow-up time of 7.4 years (3.1-11.0), and only 5 patients were above the cut-off for liver cirrhosis (14 kPa). HCV treatment uptake increased from 29% before 2006 to 68% after 2006 (p=0.001). Among those treated, only 22% started treatment during acute infection before 2006, compared to 88% after 2006 (p<0.001). MSM were much more likely to receive HCV therapy compared to patients from other transmission groups (62% vs. 29%, p=0.01). The most frequent reason for not being treated was persistent alcohol or drug abuse (30%), followed by patient’s refusal (15%). A sustained virologic response (SVR) was achieved in 69% and 25% (p=0.05) of those treated during acute and chronic infection, respectively. Finally, four patients experienced a reinfection after spontaneous clearance and three after HCV treatment. Conclusions: In this nationwide representative cohort of HIV-infected patients with an incident HCV infection, treatment uptake was low, although the proportion of patients treated during the acute phase of infection increased after 2006. MSM were more likely to be treated during acute infection. If treated early, SVR rates were high, underscoring the need of increased efforts towards early diagnosis and treatment.