Clinical course and risk factors of hepatitis C virus related liver disease in the general population: report from the Dionysos study
- S Bellentania,
- G Pozzatoa,
- G Saccoccioa,
- M Crovattob,
- L S Crocèa,
- L Mazzorana,
- F Masuttia,
- G Cristianinia,
- C Tiribellia
- aFondo Studi Fegato, University of Trieste, Trieste, Italy, bLaboratory of Microbiology and Virology, Pordenone General Hospital, Pordenone, Italy
- Dr S Bellentani, Fondo Studi Fegato, Sezione di Modena, Via Wagner 12, 41100 Modena, Italy.
- Accepted 13 January 1999
BACKGROUND The severity, clinical course, and risk of hepatitis C virus (HCV) related chronic liver disease are still rather poorly defined.
AIMS To investigate the prevalence, risk factors, and severity of HCV related liver disease in the general population, and investigate whether infection with a specific genotype is associated with an increased risk of cirrhosis or hepatocellular carcinoma.
METHODS HCV RNA determination by polymerase chain reaction (PCR) and HCV genotyping were performed in all anti-HCV positive subjects belonging to the Dionysos study (6917 subjects). Diagnosis of cirrhosis and hepatocellular carcinoma was established by liver biopsy in all cases. All the data were analysed by univariate and multivariate statistics in all the cohort. To investigate the natural history of HCV infection, anti-HCV positive subjects were followed up every six months for three years with liver function tests and ultrasonograms.
RESULTS The overall prevalence of HCV RNA positivity was 2.3%. Positivity increased progressively with age, and was higher in women (ratio of men to women = 0.7). Genotypes 1b and 2a were the most frequent (42 and 24% of HCV RNA positive patients), with a prevalence of 1 and 0.6% respectively. Intravenous drug use, blood transfusions received before 1990, history of previous hepatitis among the cohabiting, and history of animal (mainly dogs) bites were significantly (p<0.05) associated with HCV infection, independently of age and sex. Multivariate analysis showed that, independently of age, sex, and alcohol intake, genotype 1b infection, with or without coinfection with other genotypes, is the major risk factor associated with the presence of cirrhosis and/or hepatocellular carcinoma. During the three years of follow up, 57 (35%) of the HCV RNA positive subjects had consistently normal alanine aminotransferase and γ-glutamyltransferase values. Two of the 22 HCV RNA positive cirrhotic patients, all drinking more than 90 g of alcohol a day, developed hepatocellular carcinoma (incidence rate = 3.0% per year).
CONCLUSIONS In the general population of Northern Italy, HCV infection is widespread, but only less than 50% of the anti-HCV positive subjects, particularly those infected with genotype 1b, are associated with a more severe liver disease. Alcohol consumption greater that 30 g a day significantly aggravates the natural course of the disease.
- hepatitis C virus
- hepatocellular carcinoma
- polymerase chain reaction
- alanine aminotransferase
- aspartate aminotransferase
- enzyme linked immunosorbent assay
- odds ratio