The Prognostic Importance of Changes in CD4⁺ Cell Count and HIV-1 RNA Level in Women after Initiating Highly Active Antiretroviral Therapy

Background: The prognostic value of CD4⁺ cell counts and HIV-1 RNA levels attained after the initiation of highly active antiretroviral therapy (HAART) compared with before the initiation of HAART has not been well defined. Objective: To determine the prognostic value for clinical outcomes of CD4⁺ cell counts and HIV-1 RNA levels attained after initiating therapy. Design: Prospective cohort study. Setting: Women's Interagency HIV Study. Patients: 1132 participants in the Women's Interagency HIV Study. Measurements: HIV-1 RNA level, CD4⁺ cell counts, AIDS-defining illness, and death. Results: In multivariate analyses with a median follow-up of 3.9 years, women with CD4⁺ cell counts of less than 0.200 × 10⁹ cells/L compared with women with CD4⁺ cell counts of greater than 0.350 × 10⁹ cells/L after HAART initiation had a relative hazard of death from all causes of 2.66 (95% CI, 1.42 to 4.99) and a relative hazard of death from AIDS of 47.61 (CI, 5.69 to 398.40). The relative hazard of all-cause death was 3.44 (CI, 1.67 to 7.09) in women with RNA levels of more than 10 000 copies/mL compared with women with attained RNA levels of less than 80 copies/mL. The relative hazard of AIDS-related or all-cause death did not increase for women with post-HAART CD4⁺ cell counts between 0.200 and 0.350 × 10⁹ cells/L compared with women with CD4 ⁺ cell counts of greater than 0.350 × 10⁹ cells/L. Also, the relative hazard did not increase in women with post-HAART HIV-1 RNA levels between 80 and 10000 copies/mL compared with women with post-HAART HIV-1 RNA levels of less than 80 copies/mL. Of the laboratory markers, only the post-HAART CD4⁺ cell count and HIV-1 RNA level were predictive of new AIDS-defining illness. Conclusion: Post-HAART laboratory markers predicted death and new AIDS-defining illness. Pre-HAART CD4⁺ cell count and HIV-1 RNA level were not predictive of clinical outcomes if adjusted for values attained after HAART initiation, suggesting that even advanced immune suppression can be overcome with HAART that results in CD4⁺ cell counts of greater than 0.200 × 10⁹ cells/L and RNA levels of less than 10 000 copies/mL.