Differences in the factors associated with serum viral load between genotypes 1 and 2 in patients with chronic hepatitis C

Abstract

The serum hepatitis C virus (HCV) load is persistently stable in patients with untreated chronic hepatitis C, but its differences between individuals vary widely (above 4 logU/mL). Because serum viral load is an important factor for predicting clinical outcome of interferon-based antiviral therapy, this study was performed to clarify the factors associated with serum viral load in chronic hepatitis C patients. We retrospectively analyzed data from 669 chronic hepatitis C patients with HCV genotype 1 or 2 infection. Stepwise regression analysis was used to estimate the relationship between demographic, viral, or biochemical variables and serum viral load. In univariate analysis, serum lipid profiles, such as total cholesterol, low-density lipoprotein (LDL) and triglyceride levels, and hemoglobin A1c (HbA1c) were correlated with the serum HCV viral load. In multivariate analysis, HCV genotype 1 infection and higher total cholesterol levels were associated with higher viral load. After stratification by HCV genotype, the serum viral load was associated with triglyceride and HbA1c in genotype 1 and with platelet counts and LDL in genotype 2. Histological data (413 patients) showed correlation between severe liver fibrosis and decreased serum viral load in patients with HCV genotype 2 but not genotype 1 infection. These results suggest that viral kinetics is affected by different host factors for genotypes 1 and 2.