Vitamin D and calcium levels in Ugandan adults with human immunodeficiency virus and tuberculosis

BACKGROUND: Vitamin D increases cathelicidin production, and might alter mortality due to tuberculosis (TB) in human immunodeficiency virus (HIV) co-infection. However, due to abundant sun exposure, vitamin D levels might be excellent among Ugandans with HIV and TB. METHODS: We measured 25(OH)D and calcium levels in 50 HIV-negative, 50 HIV-infected and 50 TB-HIV co-infected Ugandan adults. RESULTS: Mean +/- standard deviation 25(OH)D levels were 26 +/- 7 ng/ml in HIV-negative, 28 +/- 11 ng/ml in HIV-infected and 24 +/- 11 ng/ml in TB-HIV co-infected adults (P > 0.05 all comparisons). Vitamin D deficiency (<12 ng/ml) was present in 10% of the HIV-infected subjects, 12% of the TB-HIV co-infected and none of the healthy controls (P = 0.03 for healthy vs. TB, P > 0.05 for other comparisons); 20% of the healthy controls, 22% of the HIV-positive and 38% of the TB-HIV co-infected subjects (P = 0.047 for healthy vs. TB, P > 0.05 for other comparisons) had suboptimal vitamin D levels (<20 ng/ml). No participant had hypercalcemia. Serum 25(OH)D levels correlated positively with body mass index (r = 0.22, P = 0.03) and serum calcium levels (r = 0.18, P = 0.03). CONCLUSIONS: Ugandan HIV-infected adults with and without TB commonly had suboptimal vitamin D levels. Clinical trials are needed to evaluate the effect of vitamin D on health outcomes in HIV-infected patients with low vitamin D levels.