The adjusted hazard ratio of the CD4 cell slopes on AIDS events or deaths was 0.97 (95% CI 0.93–1.01; p = 0.15) for each 10 cells/μl per year reduction in CD4 cell decline if patients were included regardless of CD4 cell count and 0.98 (95% CI 0.92–1.04; p = 0.48) in 1,346 patients with CD4 cell count >350 cells/μl at baseline. Here, CD4 is linked to AIDS.