['Hepatic steatosis is common in patients infected with hepatitis C virus (HCV). The effect of steatosis on anti-HCV therapy efficacy is unclear.', 'We studied host and viral factors associated with steatosis and the effect of steatosis on treatment efficacy using the database of a large prospective trial in patients with HCV genotypes 2 and 3.', 'Out of 885 patients assessed for steatosis, a total of 614 patients or 69% had steatosis. Patients with genotype 3 were more likely to have steatosis than those with genotype 2 (79 vs. 59%, P<0.001). Using the logistic regression model, steatosis was associated with genotype 3 (P<0.0001), older age (P=0.0025), heavier weight (P<0.0001), higher HCV RNA (P<0.0001), and higher ALT levels (P=0.015). By univariate analysis, steatosis was associated with lower sustained virological response (SVR) in patients with genotype 3, but not in patients with genotype 2. When all factors associated with steatosis and SVR were evaluated by logistic regression analysis; genotype, age, bodyweight, histological diagnosis, ALT quotient, baseline HCV RNA and treatment duration were associated with the probability of SVR, but gender, race and steatosis were not. Further analysis showed that steatosis remained a non-significant factor while baseline viral load was significantly associated with the probability of an SVR.'] Does hepatic steatosis in patients with chronic hepatitis C virus genotype 2 or 3 affect viral response in patients treated with peginterferon alpha-2a ( 40KD ) ( PEGASYS ) plus ribavirin ( COPEGUS ) for 16 or 24 weeks?