Evidence of a possible therapeutic role of vitamin D in a cohort of adult Caucasian vitiligo patients.

Reduced serum 25(OH)D levels have been largely reported in vitiligo, which is an autoimmune skin disorder characterized by the appearance of achromic macules. Since vitamin D can positively modulate immune function and stimulate melanogenesis in vitro, a possible role of sufficient vitamin D levels in promoting the stability of the disease and repigmentation process might be hypothesized in vitiligo. Hence, we conducted an observational study on medical records related to 101 vitiligo patients, in order to correlate baseline 25(OH)D levels with the baseline vitiligo activity and repigmentation of vitiligo macules on a 6-month follow-up. According to our results, at baseline we found that active vitiligo was significantly associated with 25(OH)D deficiency (≤20 ng/mL) (P = 0.036) or insufficiency (21-29 ng/mL) (P = 0.041), while stable disease was significantly associated with sufficient 25(OH)D levels (30-100 ng/mL) (P = 0.043). After 6 months, vitiligo patients with sufficient 25(OH)D levels (30-100 ng/mL) achieved a significantly higher degree of repigmentation. In conclusion, our study provides a novel evidence of a significant positive association of sufficient 25(OH)D levels with the stability of the disease and a satisfactory repigmentation process in Caucasian adult vitiligo patients and strengthen the need to assess vitamin D status in vitiligo. The correlation between sufficient vitamin D levels and a satisfactory course of the disease opens the way for future randomized controlled trials assessing a possible beneficial role of vitamin D supplementation on vitiligo.