Vitamin D supplementation and CD4 count in children infected with human immunodeficiency virus

Objective: To evaluate, in a randomized fashion, the impact of vitamin D supplementation on CD4 count and measures of vitamin D homeostasis in children infected with human immunodeficiency virus (HIV).

Study design: Children infected with HIV (n = 54) were randomized to receive no supplementation (group 1), vitamin D 5600 IU/week (group 2), or vitamin D 11 200 IU/week (group 3) for 6 months. Viral load, CD4 percent, CD4 count, 25-hydroxyvitamin D (25[OH]D), 1,25-dihydroxyvitamin D, and other measures of vitamin D metabolism were measured at baseline and 6 months later.

Results: A total of 53 participants completed the study. The mean age, CD4 percent, CD4 count, and log(10) viral load at baseline were 10.3 ± 3.9 years, 33% ± 10%, 927 ± 468 cells/μL, and 1.63 (95% CI, 0.76-2.50), respectively. The mean baseline 25(OH)D level was 53.1 ± 24.8 nmol/L; 85% of participants were vitamin D insufficient or deficient (<75 nmol/L). Serum levels of 25(OH)D increased significantly in participants who received supplementation with vitamin D (P = .0002 and P < .001 for participants receiving 800 IU/day and 1600 IU/day, respectively), but not in participants who did not receive supplementation (P = .27). Participants treated with 1600 IU/day of vitamin D achieved a higher mean increase in 25(OH)D than participants treated with 800 IU/day (P = .02). However, only 67% of the group supplemented with higher dose achieved vitamin D sufficiency. Vitamin D supplementation did not lead to an increase in CD4 percent or CD4 count.

Conclusion: In children infected with HIV with relatively preserved immune function, vitamin D supplementation in doses as high as 1600 IU/day does not impact CD4 count. Vitamin D insufficiency is common in this population, and achieving vitamin D serum levels of >75 nmol/L may require a daily intake ≥1600 IU.