Is hepatitis C virus co-infection associated with survival in HIV-infected patients treated by combination antiretroviral therapy?

Objective: To study whether hepatitis C virus (HCV) co-infection or the severe elevation of transaminases is associated with survival after the initiation of antiretroviral combination therapy.

Design: Prospective hospital-based cohort (Aquitaine Cohort).

Methods: HIV-infected adults started on an antiretroviral combination before 30 June 1999. HCV infection was defined as antibody detection or positive HCV RNA. Severe elevation of transaminases was defined as a value of aspartate or alanine aminotransferase (AST, ALT) above five times the upper limit of normal values. Survival was studied using a Cox model, including at least baseline HCV status and transaminases as a time-dependent covariate.

Results: Overall, 995 patients were analysed, including 576 HCV-positive individuals (58%). At baseline, HCV-positive patients were younger, more often injecting drug users and women, and had more frequently elevated transaminases. A shorter survival was associated with AIDS stage [hazard ratio (HR) versus non-AIDS 1.67; 95% confidence interval (CI) 1.03; 2.68], lower CD4 cell count (HR for 50 cells/mm3 lower 1.33; CI 1.17; 1.51), lower haemoglobin (HR for 1 g/dl lower 1.20; CI 1.07; 1.35), lower platelet count (HR for 10 000 cells/mm3 lower 1.04; CI 1.01; 1.07), and AST during follow-up (HR for > or = 200 IU/l 2.30; CI 1.32; 4.03). HCV co-infection (HR 1.20; CI 0.75; 1.92) was not statistically associated with survival.

Conclusion: The occurrence of a severe elevation of transaminases was associated with poorer survival, although HCV was not. If liver toxicity may be treatment induced, plasma drug concentrations could guide dosage adjustments of antiretroviral treatments currently prescribed to optimize their use.