Steatosis is an important cofactor in hepatitis C virus (HCV) because it is associated with fibrosis and reduces early and sustained virologic response. Recent studies suggest that HCV genotype 1 is not steatogenic if additional risk factors are not present. Because hypoadiponectinemia was found to be a feature of nonalcoholic steatohepatitis (NASH) independent of insulin resistance, its level in patients with hepatitis C genotype can reveal the optimal therapeutic strategy. This study was conducted to determine the role of the relationship between steatosis and serum adiponectin levels in the progression of liver damage in HCV genotype 1 without known risk factors for NASH. Patients (n=50) with biopsy-proven chronic hepatitis C (CHC), positive HCV RNA, and raised alanine aminotransferase were enrolled. They were carefully selected to rule out possible confounding factors for the presence of steatosis and additional systemic or liver disease. Associations between serum adiponectin levels and grade of steatosis, histologic activity index (HAI), fibrosis grade of liver biopsies, patient age, HCV viral load, and serum transaminase activities were studied. Also, adiponectin levels were compared with those of a control group of 30 healthy volunteers with normal ultrasound findings of the upper abdomen who had no known NASH risk factors. The investigators found that adiponectin levels in patients with CHC genotype 1 were similar to those in healthy subjects. No significant association was found between adiponectin levels and severity of steatosis, HCV RNA levels, HAI, transaminases, and fibrosis. Steatosis was present in 41 patients (82%) with CHC. Multivariate analysis of data on 50 patients revealed that severity of steatosis was independently related to age alone (P=.03). A correlation between HCV RNA load and HAI was observed (P=.02; r=0.712). HAI also was associated with stage of fibrosis (P=.00; r=0.612). in cases of chronic HCV genotype 1 hepatitis, steatosis is a common histologic feature, although no risk factors are known. Results presented here cannot establish an association between adiponectin and se verity of steatosis when risk factors for steatosis are unknown. Additional studies are needed to discover a metabolic treatment that would seek to improve the progression of hepatic steatosis in CHC infection.