Mortality in patients with chronic and cleared hepatitis C viral infection: a nationwide cohort study.

BACKGROUND & AIMS It is unknown whether mortality differs between patients with chronic hepatitis C virus (HCV) replication and those who cleared the virus after infection. We examined the impact of chronic HCV replication on mortality among Danish patients testing positive for HCV antibodies. METHODS This nationwide cohort study focused on Danish patients with at least one HCV RNA measurement available after testing positive for HCV antibodies between 1996 and 2005. To capture long-term prognosis, eligible patients needed to be alive 1year after HCV RNA assessment. We estimated mortality rate ratios (MRRs) using Cox regression (for overall mortality) and subdistribution hazard ratios (SDHRs) for cause-specific mortality, controlling for gender, age, comorbidity, calendar period, alcohol abuse, injection drug use, and income. RESULTS Of the 6292 patients under study, 63% had chronic HCV-infection and 37% had cleared the virus. Five-year survival was 86% (95% confidence interval (CI): 84-87%) in the chronic HCV group and 92% (95% CI: 91-94%) in the cleared HCV group. Chronic HCV-infection was associated with higher overall mortality (MRR: 1.55, 95% CI: 1.28-1.86) and liver-related death (SDHR: 2.42, 95% CI: 1.51-3.88). Chronic HCV-infection greatly increased the risk of death from primary liver cancer (SDHR: 16.47, 95% CI: 2.24-121.00). CONCLUSIONS Patients with chronic HCV-infection are at higher risk of death than patients who cleared the infection. The substantial association found between chronic HCV-infection and death from primary liver cancer supports early initiation of antiviral treatment in chronically HCV-infected patients.