Background: Vitamin D has immunomodulatory effects both in the innate and adaptive immune systems, and there is growing scientific evidence demonstrating its relevance in inflammatory processes such as AD.
Hypothesis: If vitamin D3 promotes the skin immune system, then it should improve the response to treatment of patients with AD.
Methods: A randomized, double-blind placebo-controlled clinical trial was conducted, which included 65 patients with AD according to Hanifin-Rajka criteria and the severity scale (SCORAD). The patients were divided into two groups to receive either vitamin D3 5000 IU/day (n = 33) or placebo (n = 32), plus baseline therapy (topical steroid, soap substitute, and emollient) during 3 months.
Results: Fifty-eight of the 65 enrolled subjects were included in the analysis. At the end of the intervention, the treated group achieved higher levels of 25(OH)D (P < 0.001). At week 12, those patients who registered serum levels of 25(OH)D ≥20 ng/ml, regardless of whether or not they had received supplementation, showed a lower SCORAD compared to those with levels <20 ng/ml (P < 0.001). Eighty percent of the patients with serum levels <20 ng/ml (n = 9) had moderate-severe AD despite standard treatment. Vitamin D levels ≥20 ng/ml associated with baseline therapy strongly favored remission of atopic dermatitis (P = 0.03). No significant differences were found between patients with serum levels of ≥20 ng/ml vs. ≥30 ng/ml.
Conclusions: Reaching serum levels of 25(OH)D > 20 ng/ml in conjunction with standard therapy is sufficient to achieve a reduction in severity (SCORAD) in patients with AD.
© 2018 The International Society of Dermatology.