The role of the viral genotype, especially genotype 1b, in the severity of liver injury induced by chronic hepatitis C virus (HCV) infection is unclear, probably because of confounding factors such as the date and mode of contamination. Host genetic or environmental factors such as heterozygous MZ alpha1-antitrypsin deficiency or alcoholism, could also be potential risk factors for the development of cirrhosis. The aim of this study was to compare the prevalence of genotypes, alpha1-antitrypsin phenotype, past hepatitis B virus infection, and alcohol consumption in cirrhotic and noncirrhotic patients with chronic hepatitis C. We conducted a case-control study comparing 84 consecutive cirrhotic patients with chronic hepatitis C (cases) with 84 noncirrhotic patients with chronic hepatitis C (controls) selected from a cohort of 464 patients hospitalized during the same period. Controls were paired with cases according to age, sex, risk factors, and date of infection. HCV genotypes were determined using the InnoLiPA technique (Innogenetics, Zwijnaarde, Belgium) and classified according to the method of Simmonds. Patients were divided in three groups according to alcohol consumption: <30 g/d (light), 30 to 80 g/d (moderate), and >80 g/d (heavy). Cirrhotic and noncirrhotic patients were not significantly different in terms of genotype distribution (1a/1b/2a/3a/others/undetermined: 10/48/7/17/0/2 versus 11/43/10/10/5/5), alpha1-antitrypsin phenotype distribution (MM/MS/MZ: 84%/14%/2% vs. 87%/11%/2%, respectively), and prevalence of antibody to hepatitis B core antigen positivity (29% vs. 23%). Alcohol consumption was significantly different between cases and controls (L/M/H: 58%/27%/16% vs. 76%/15%/9%, respectively; P < .05). Two conclusions regarding patients with chronic hepatitis C virus infection can be drawn from this study: 1) viral genotype, especially 1b, past hepatitis B virus infection, and heterozygous MZ alpha1-antitrypsin deficiency are not risk factors for cirrhosis; and 2) alcohol consumption, even moderate, is a risk factor for cirrhosis.