Discontinuation of potent antiretroviral therapy: predictive value of and impact on CD4 cell counts and HIV RNA levels.

OBJECTIVE: To characterize predictors and consequences of discontinuing antiretroviral therapy (ART) in terms of CD4 cell count, HIV RNA, and reported side-effects in a large cohort of HIV-infected women.
DESIGN: Cohort study.
METHODS: A total of 1058 HIV-infected women initiated potent ART before September 1999. For each 6 month period after October 1996 we determined the proportion of potent ART users who downshifted to non-potent ART and who discontinued all ART. We examined the role of CD4 cell count and HIV RNA with regard to ART discontinuation.
RESULTS: Between October 1996 and September 1999, 1058 individuals contributed 3362 visits at which potent ART was reported in the previous 6 months. Overall rates of 6 month downshifting and discontinuation were 10.0% and 6.7%. The proportion of individuals discontinuing all ART increased from 2.9% in late 1996 to 9.1% in mid 1999 (P < 0.001). Individuals with high HIV RNA levels were more likely to discontinue (P < 0.05). Compared to those who continued on potent ART, individuals who discontinued experienced large declines (P < 0.001) in CD4 cell counts and were more than three times more likely (P < 0.001) to experience HIV RNA increases. However, over one-third of those discontinuing ART reported side-effects and this subset had smaller CD4 cell count declines as compared to discontinuers not reporting side-effects (P = 0.147).
CONCLUSIONS: In a large cohort of HIV-infected women, an increasing proportion of potent ART users discontinued ART over 3 years. Higher HIV RNA levels predicted discontinuation. Immediate immunological/virological deleterious consequences were observed. Side-effects were the most common reason for discontinuation and CD4 cell count declines were larger among those who did not cite side-effects as the reason for discontinuation.