Decrease of vitamin D concentration in patients with HIV infection on a non nucleoside reverse transcriptase inhibitor-containing regimen

Background: Vitamin D is an important determinant of bone health and also plays a major role in the regulation of the immune system. Interestingly, vitamin D status before the start of highly active antiretroviral therapy (HAART) has been recently associated with HIV disease progression and overall mortality in HIV-positive pregnant women. We prospectively studied vitamin D status in HIV individuals on HAART in Belgium.We selected samples from HIV-positive adults starting HAART with a pre-HAART CD4 T-cell count >100 cells/mm 3 followed up for at least 12 months without a treatment change. We compared 25-hydroxyvitamin D plasma [25-(OH)D] concentration in paired samples before and after 12 months of HAART. 25-(OH)D levels are presented using two different cut-offs: <20 ng/ml and