Vitamin D Status and Incidence of Pulmonary Tuberculosis, Opportunistic Infections, and Wasting Among HIV-Infected Tanzanian Adults Initiating Antiretroviral Therapy

Abstract

Background. Maintaining vitamin D sufficiency may decrease the incidence of pulmonary tuberculosis and other infectious diseases. We present the first prospective study of vitamin D among human immunodeficiency virus (HIV)-infected adults receiving antiretrovirals in sub-Saharan Africa.Methods. Serum 25-hydroxyvitamin D (25(OH)D) level was assessed at antiretroviral therapy (ART) initiation for 1103 HIV-infected adults enrolled in a trial of multivitamins (not including vitamin D) in Tanzania. Participants were prospectively followed at monthly visits at which trained physicians performed a clinical examination and nurses took anthropometric measurements and assessed self-reported symptoms. Cox proportional hazards models estimated hazard ratios (HRs) of morbidity outcomes. Results. After multivariate adjustment, vitamin D deficiency (defined as a concentration of < 20 ng/mL) had a significantly greater association with incident pulmonary tuberculosis, compared with vitamin D sufficiency (HR, 2.89; 95% confidence interval [CI], 1.31-7.41; P = .027), but no association was found for vitamin D insufficiency (defined as a concentration of 20-30 ng/mL; P = .687). Deficiency was also significantly associated with incident oral thrush (HR, 1.96; 95% CI, 1.01-3.81; P = .046), wasting (HR, 3.10; 95% CI, 1.33-7.24; P = .009), and > 10% weight loss (HR, 2.10; 95% CI, 1.13-3.91; P = .019). Wasting results were robust to exclusion of individuals experiencing pulmonary tuberculosis. Vitamin D status was not associated with incident malaria, pneumonia, or anemia. Conclusions. Vitamin D supplementation trials for adults receiving ART appear to be warranted.