Modeling the impact of early antiretroviral therapy for adults coinfected with HIV and hepatitis B or C in South Africa.

OBJECTIVE: There has been discussion about whether individuals coinfected with HIV and hepatitis C virus (HCV) or hepatitis B virus (HBV) (∼30% of all people living with HIV) should be prioritized for early HIV antiretroviral therapy (ART). We assess the relative benefits of providing ART at CD4 count below 500  cells/μl or immediate ART to HCV/HIV or HBV/HIV-coinfected adults compared with HIV-monoinfected adults. We evaluate individual outcomes (HIV/liver disease progression) and preventive benefits in a generalized HIV epidemic setting. METHODS: We modeled disease progression for HIV-monoinfected, HBV/HIV-coinfected, and HCV/HIV-coinfected adults for differing ART eligibility thresholds (CD4 <350  cells/μl, CD4 <500  cells/μl, immediate ART eligibility upon infection). We report disability-adjusted life-years averted per 100 person-years on ART (DALYaverted/100PYonART) as a measure of the health benefits generated from incremental changes in ART eligibility. Sensitivity analyses explored impact on sexual HIV and vertical HIV, HCV, and HBV transmission. RESULTS: For HBV/HIV-coinfected adults, a switch to ART initiation at CD4 count below 500  cells/μl from CD4 below 350  cells/μl generates 9% greater health benefits per year on ART (48 DALYaverted/100PYonART) than for HIV-monoinfected adults (44 DALYaverted/100PYonART). Additionally, ART at CD4 below 500  cells/μl could prevent 25% and 32% of vertical transmissions of HIV and HBV, respectively. For HCV/HIV-coinfected adults, ART at CD4 below 500  cells/μl generates 10% fewer health benefits (40 DALYaverted/100PYonART) than for HIV monoinfection, unless ART reduces progression to cirrhosis by more than 70% (33% in base-case). CONCLUSIONS: The additional therapeutic benefits of ART for HBV-related liver disease results in ART generating more health benefits among HBV/HIV-coinfected adults than HIV-monoinfected individuals, whereas less health benefits are generated amongst HCV/HIV coinfection in a generalized HIV epidemic setting.