Hepatitis B prevalence and influence on HIV treatment outcome and mortality in the Chilean AIDS Cohort.

OBJECTIVES: To analyze the prevalence of hepatitis B virus (HBV) co-infection and its influence on mortality and treatment outcome within a large AIDS cohort in Chile. METHODS: Clinical and epidemiological data from the Chilean AIDS Cohort were retrospectively analyzed. Adult patients tested for hepatitis B surface antigen (HBsAg) during the time period of October 2001 to October 2007 were included. RESULTS: Of 5115 cohort patients, 1907 met the inclusion criteria. The prevalence of HBV co-infection was 8.4%. Overall mortality rates were 2.15 and 1.77 per 100 person-years for HBsAg-positive and HBsAg-negative HIV patients, respectively, with a mortality rate ratio of 1.22 (95% confidence interval 0.58-2.54). Kaplan-Meier survival and Cox regression analysis did not show significant differences between the groups. Virological and immunological responses to antiretroviral therapy (ART) were not influenced by HBsAg status, but in co-infected patients, initial ART was more frequently changed. CONCLUSIONS: The prevalence of hepatitis B co-infection was 8.4%, indicating a markedly elevated hepatitis B risk compared to the general population in Chile. Neither treatment outcome nor overall mortality was influenced by hepatitis B co-infection. Still, patients with hepatitis B co-infection had less stable ART regimens, which might be related to a higher risk of hepatotoxic drug effects.