CD4 and AIDS: To assess whether the CD4/CD8 ratio might maintain the independent association with non-AIDS events among subjects with low nadir CD4, we re-applied the model in the subgroup of patients with nadir CD4 below 200 cells/μL (N = 212) and the CD4/CD8 ratio remained independently associated to non-AIDS events (per quartile decrease; OR 2.8; 95% CI 1.2–2.2).