Hepatitis C virus (HCV) infection is associated with a higher risk of cardiovascular disease (CVD) events. Treatment with directly acting antiviral (DAA) regimens has been shown to reduce this risk in most, but not all studies. How liver fibrosis stage affects risk of incidence CVD events after treatment with DAA regimens is unknown. We undertook this study to determine the effect of baseline liver fibrosis stage upon the risk of incident CVD events in DAA-treated HCV infected persons, and compare it with untreated and those treated with older pegylated interferon-based (PEG) regimens.
Within ERCHIVES (Electronically Retrieved Cohort of HCV Infected Veterans), we identified all persons treated for HCV for >=7 weeks and propensity-score matched group who never received HCV treatment. We excluded those with HIV, HBV and previously diagnosed CVD. Incidence rate (per 1,000 person-years) and risk factors for CVD events (Cox proportional hazards analysis) were stratified by liver fibrosis stage. Liver fibrosis stage was determined by FIB-4 score. CVD events were identified using ICD-9CM/ICD-10 codes. Kaplan-Meier plots were generated to show and compare CVD-free survival by fibrosis stage and treatment regimen.
Among 32,575 treated and same number of propensity-score matched untreated persons in the final dataset, median age was 58 years, 27% were Black race and 96% were male. The incidence rate for CVD events/1,000 person-years (95% CI) among the treated was as follows: FIB-4<1.25: 19.3 (17.2,21.4); FIB-4 1.26-3.25: 19.9 (18.4,21.5); FIB-4>3.25: 24.5 (21.5,27.6). Rates among untreated were as follows: FIB-4<1.25: 25.6 (23.8,27.5); FIB-4 1.26-3.25: 33.2 (31.2,35.1); FIB-4>3.25: 44 (39.6,48.3). The absolute difference in rate was 6.3 for FIB-4<1.25, 13.3 for FIB-4 1.26-3.25 and 19.5 for FIB-4>3.25.
Risk of CVD among HCV infected persons is higher with increasing liver fibrosis stage. Treatment reduces the risk of incident events at all fibrosis stages, but the benefit is highest for those with most advanced fibrosis. HCV infected persons with more advanced liver fibrosis should be targeted for treatment to reduce future risk of CVD events.