Age, Sex, and Nutritional Status Modify the CD4+ T-cell Recovery Rate in HIV–Tuberculosis Co-infected Patients on Combination Antiretroviral Therapy

Abstract

Background We examined baseline age and combination antiretroviral therapy (cART) as determinants of CD4+T-cell recovery during six months of tuberculosis (TB) therapy with/without cART. We determined whether this association was modified by patient sex and nutritional status. Methods This longitudinal analysis included 208 immune-competent, non-pregnant, ART-naive HIV-positive patients from Uganda with a first episode of pulmonary TB. CD4+T-cell count was measured using flow cytometry. Age was defined as ≤24, 25–29, 30–34, 35–39 vs. ≥ 40 years. Nutritional status was defined as normal (>18.5kg/m2) vs. underweight (≤18.5kg/m2) using body mass index (BMI). Multivariate random-effects linear mixed models were fitted to estimate differences in CD4+T-cell recovery in relation to specified determinants. Results cART was associated with a monthly rise of 15.7 cells/μL (p<0.001). Overall, age was not associated with CD4+T-cell recovery during TB therapy (p=0.655). However, among patients on cART, age-associated CD4+T-cell recovery rate varied by sex and nutritional status such that age <40 vs. ≥ 40 years predicted superior absolute CD4+T-cell recovery among females (p=0.006) and among patients with BMI≥18.5kg/m2 (p<0.001). Conclusions TB infected HIV-positive patients ≥ 40 years have a slower rate of immune restoration given cART-particularly if BMI>18.5kg/m2 or female. They may benefit from increased monitoring and nutritional support during cART.