Impact of hepatitis C virus genotype 3 on liver disease progression in a Chinese national cohort

Background: Hepatitis C virus (HCV) genotype 3, particularly subtype 3b, is increasing in prevalence and distribution in China. This study evaluated the prevalence, regional distribution, clinical characteristics, host factors, treatment outcomes, and disease progression of patients with HCV genotype 3 in China.Methods: A 5-year follow-up was preceded by a cross-sectional study. Treatment choices were at the discretion of treating physicians. Estimated infection time to overall-disease-progression (defined by ≥1 of: newly diagnosed cirrhosis; cirrhosis at baseline, Child-Turcotte-Pugh score increased 2 points or more; progression from compensated cirrhosis to decompensated cirrhosis; hepatocellular carcinoma; liver transplantation; or death) was calculated using the Kaplan-Meier method. Cox regression analyses were conducted to evaluate the risk factors for disease progression.Results: The cross-sectional study enrolled 997 patients, including 91 with HCV genotype 3 infection. Among them, subtype 3b (57.1%) was more dominant than subtype 3a (38.5%). Five hundred and twelve patients were included into the follow-up phase. Among patients analyzed for estimated infection time to overall-disease-progression, 52/304 (17.1%) patients with HCV genotype 1 and 4/41 (9.8%) with HCV genotype 3 (4/26 with genotype 3b, 0/13 with genotype 3a, and 0/2 with undefined subtype of genotype 3) experienced overall-disease-progression. Patients with HCV genotype 3 were younger than those with genotype 1 (mean age: 39.5 ± 8.7vs. 46.9 ± 13.6 years) and demonstrated more rapid disease progression (mean estimated infection time to overall-disease-progression 27.1vs. 35.6 years).Conclusions: HCV genotype 3, specifically subtype 3b, is associated with more rapid progression of liver disease. Further analysis to compare HCV subtype 3a and 3b is needed in high prevalence regions.Trial registration: NCT01293279, https://clinicaltrials.gov/ct2/show/NCT01293279; NCT01594554, https://clinicaltrials.gov/ct2/show/NCT01594554.