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.