Age Differences by Sex in Antiretroviral-Naïve Participants: Pooled Analysis from Randomized Clinical Trials

Age and sex effects on antiretroviral therapy (ART) response are not well elucidated. Our pooled analysis of 40 randomized clinical trials measured the association of age and sex on CD4+ T cell count changes and virologic suppression using multivariable regression modeling. The average increase in CD4+ T cell count from baseline to week 48 was 17.3 cells/mm3 lower and clinically insignificant (95% confidence interval −30.8 to −3.8) among women ages ≥ 50 years (n = 573), compared to women ≤ 35 years (n = 3,939). Results were similar for men. Virologic suppression odds were 60% and 21% times greater among participants ≥50 years compared to ≤35 years, in women and men, respectively. In both sexes, larger increases in CD4+ T cell count changes were observed in younger, compared to older, participants; however, virologic suppression was higher in older, compared to younger, participants suggesting a non-sex-specific age effect response to ART.