Serologic and clinical outcomes of 1536 Alaska natives chronically infected with hepatitis B virus

Background: Knowledge of the outcome of chronic hepatitis B virus (HBV) inf ection Is limited. Objective: To determine the incidence of and risk factor s for adverse events (hepatocellular carcinoma and end-stage liver disease) and clearance of hepatitis B e antigen (HBeAg) and surface antigen (HBsAg) in carriers of HBV. Design: Population-based cohort study of hepatitis B carriers who were obse rved for a median of 12.3 years as part of an active surveillance program t o detect carriers with hepatocellular carcinoma. Setting: 126 communities in Alaska. Patients: 1536 Alaska Natives with chronic hepatitis B. Measurements: Bivariate comparisons, multivariable models, and other statis tical methods were used to examine the relationships of risk factors to out comes and clearance of HBeAg and HBsAg. Results: 1536 chronic HBV carriers were followed up for 19 430 person-years from their first HBsAg-positive test result. At the first serologic test 6 41 were HBeAg positive and 893 were anti-HBe positive. Older carriers were more likely than younger carriers to clear HBeAg (P < 0.001). The observed probability of clearing HBeAg within 10 years of diagnosis was 72.5%. Clear ance of HBsAg occurred in 106 (7%) of all carriers and was positively assoc iated with older age and positive result on initial anti-HBe test. The inci dence of adverse events was 2.3 per 1000 carrier-years, and the incidence o f hepatocellular carcinoma was 1.9 per 1000 carrier-years (2.3 in men and 1 .2 In women). Risk for hepatocellular carcinoma increased with age, among t hose of Yupik Eskimo ethnicity, and among carriers who reverted from anti-H Be to HBeAg. Conclusion: in HBsAg-positive carriers, observed clearance of HBeAg was mor e than 70% during the first 10 years of follow-up.