Ethnicity and body mass index are associated with hepatitis C presentation and progression

Ethnicity and the metabolic syndrome are believed to affect progression of hepatitis C virus (HCV) infection, but the interaction between these factors is unknown. We evaluated the association between elements of the metabolic syndrome and ethnicity in the histologic progression of HCV in a large, diverse cohort.

We retrospectively evaluated clinical data and liver biopsy samples from 812 patients who had no cause of liver disease other than HCV infection. Liver biopsies were scored for steatosis, necroinflammatory activity, and fibrosis. For each patient with a known risk factor for viral acquisition, fibrosis index was calculated as an indicator of disease progression.

Hispanics had significantly higher fibrosis index (0.13 +/- 0.09) than non-Hispanic whites (0.11 +/- 0.07) and African Americans (0.10 +/- 0.06; P = .001). Fibrosis index correlated with body mass index (BMI), older age at infection, ethnicity, and degree of steatosis. Cirrhosis was present in 50% of Hispanics, 38% of non-Hispanic whites, and 24% of African Americans (P < .001). The presence of cirrhosis was associated additionally with older age, longer duration of infection, BMI, alcohol consumption, and diabetes. In multivariate analysis, only BMI and ethnicity were associated with both fibrosis index and presentation with cirrhosis. Patients with higher BMIs, diabetes mellitus, and steatosis had higher degrees of necroinflammation.

Ethnicity and BMI each were associated with the progression of fibrosis and the presence of cirrhosis. Hispanics had the highest fibrosis index and prevalence of cirrhosis, whereas African Americans had the lowest. Ethnic differences in fibrosis index and cirrhosis persisted after controlling for elements of metabolic syndrome.