Vitamin D Level and Supplementation in Pediatric Atopic Dermatitis: A Randomized Controlled Trial

Background: Atopic dermatitis (AD) is a chronic inflammatory skin condition characterized by a pruritic eczematous rash. Evidence surrounding the role of serum vitamin D (VD) in modifying disease severity is inconsistent. Objectives: To determine whether VD levels are correlated with AD severity and the effects of VD supplementation on disease modification. Methods: This was a 2-phase study, using a cross-sectional design to evaluate the relationship between VD level and severity, as well as a double-blinded, randomized control trial to elucidate the effects of VD supplementation. Patients aged 0 to 18 years with AD were included in phase 1, and disease severity and serum VD levels were determined. Those with renal, liver, or other dermatologic conditions were excluded. Patients with abnormal (<72.7 nmol/L) VD levels were eligible for phase 2 and to be randomized to either VD supplementation of 2000 IU/d or placebo. VD level and severity were assessed at baseline and 3 months. Results: The 77 patients included in phase 1 had a mean (SD) age of 7.4 (4.5) years, and 45.5% (33/77) were female. Increased severity was significantly correlated with lower VD levels (P = .015). Of the 45 patients included in phase 2, 21 and 24 were assigned to the supplementation and placebo arm, respectively. The mean (SD) change in severity did not differ significantly between the supplementation (15.35 [9.71]) and placebo (15.13 [8.97]) groups after 3 months of intervention (P = .7). Conclusion: Although VD levels correlated with AD severity, VD supplementation did not significantly improve disease severity.