Increase and plateau of CD4 T-cell counts in the 3 1/2 years after initiation of potent antiretroviral therapy

We evaluated CD4 cell counts over a 3 1/2 year period following the initiation of potent antiretroviral therapy (ART) in the Multicenter AIDS Cohort Study. The study population included 314 HIV-infected gay men who provided CD4 cell counts for at least 2 years after the initiation of potent ART. Trends in CD4 cell counts and plasma HIV-RNA were analyzed by regression methods that incorporated the statistical dependencies of outcomes measured over time within individuals. Regardless of CD4 cell count at initiation of potent ART, CD4 cell counts increased significantly (p < .05) in the first 2 years after initiation. However, between 2 and 3 1/2 years after initiation, these counts neither increased nor decreased. The pattern of the proportion with plasma HIV-RNA <400 copies/ml was similar to CD4 cell count (i.e., increased significantly after initiation and plateau in the subsequent 1 1/2 years). The single most important predictor of the steady state CD4 cell count that was maintained between 2 and 3 1/2 years after initiation was the change in plasma HIV-RNA in the first year after initiation of potent ART.