RISK-FACTORS AND PREDICTORS OF OUTCOME IN AN AUSTRALIAN COHORT WITH HEPATITIS-C VIRUS-INFECTION

Objectives: To define demographic and epidemiological features of an A ustralian population with chronic hepatitis C virus (HCV) infection an d determine predictors of histological and clinical outcome. Design: C ohort study. Patients and setting: 342 consecutive HCV antibody-positi ve patients referred to the liver clinic of a major metropolitan gener al hospital. Outcome measures: Demographic data, serial alanine aminot ransferase (ALT) levels, full blood count for all patients. Percutaneo us liver biopsy in 152 patients (44%). Results: 51% of patients had pr eviously used injecting drugs, 15% had received a blood transfusion an d 27% had no definite percutaneous risk factor (sporadic group). The i njecting drug users (IDUs) were younger and more likely to have been b orn in Australia. The sporadic group were older and frequently were bo rn in Mediterranean or Asian countries. A history of excessive alcohol use was common, particularly among IDUs (60%). Of 152 patients who ha d a liver biopsy, 49 had cirrhosis and 103 had chronic hepatitis. Some patients with a normal ALT level had marked necro-inflammatory activi ty. On univariate analysis, the presence of cirrhosis correlated with older age (P < 0.0001), lack of an identifiable risk factor (P < 0.001 ) and birth in a Mediterranean or Asian country (P < 0.0001). On multi variate analysis, the only significant predictor of cirrhosis was age (P < 0.001). Among patients with an identifiable percutaneous risk fac tor, cirrhosis was seen at a median time of 18 years after first expos ure to risk, compared with 13 years in patients with chronic hepatitis (P < 0.01). Patients with clinical evidence of portal hypertension we re, on average, 15 years older than those with histological cirrhosis only (P < 0.01). Conclusions: Injecting drug use is the major risk fac tor for chronic HCV infection in Australia. In patients with an identi fiable risk factor, the most significant factor associated with a biop sy finding of cirrhosis is the time since first exposure to HCV.