CD4 and AIDS: Multivariate analyses (adjusted for age, sex, nadir CD4, proximal CD4 count, year of ART initiation and ART duration) confirmed the independent association of a low CD4/CD8 ratio with the risk of non-AIDS morbidity (per CD4/CD8 ratio quartile decrease, OR, 2.9; 95% CI, 1.3–6.2) and non-AIDS mortality (OR, 2.8; 95% CI, 1.5–5.3).