HIV treatment outcomes after 10 years on ART in the TREAT Asia Observational Database (TAHOD) and Australian HIV Observational Database (AHOD)

Background Increasing numbers of people with HIV have received prolonged antiretroviral therapy (ART). We assessed long-term immunological and survival outcomes among people with HIV from Asia (TAHOD) and Australia (AHOD). Methods People with HIV receiving ART for ≥10 years were included. Factors associated with CD4 counts in years 11-15 of ART were analysed using repeated measure linear regression. Survival after 10 years was analysed using competing risk regression. Results There were 7139 people included: 4867 (68%) from TAHOD and 2272 (32%) from AHOD. Higher CD4 after 10 years were observed if the nadir CD4 in the first decade was higher (CD4 (cells/μL) 101-200: difference=35, 95%CI 18, 51; >200: difference=125, 95%CI 107, 142) compared to ≤50. The same patterns were observed in those who achieved CD4 ≥500 cells/μL which subsequently decreased to <500 (difference=225, 95%CI 213, 236); or those who achieved and maintained CD4 ≥500 cells/μL (difference=402, 95%CI 384, 420), compared to always <500 in the previous decade. Prior protease inhibitor (PI) -based regimen (difference=-17, 95%CI -33, -1) compared to no PI, and previous treatment interruptions (TI) of 14 days to 3 months and >6 months were associated with lower CD4 counts after 10 years (difference = -38, 95%CI -62, -15; and difference=-44, 95%CI -61, -27, respectively) compared to no TI. The mortality rate was 1.04 per 100 person-years. Virological failure was associated with subsequent mortality (sub-hazard ratio=1.34, 95%CI 1.04, 1.71). Conclusions Sustaining high CD4 levels and minimising TI has far-reaching benefits well beyond the first decade of ART.