COMMENTARY

Vitamin D Deficiency and Vitiligo Vulgaris

Graeme M. Lipper, MD

Disclosures

August 13, 2010

A Pilot Study Assessing the Role of 25 Hydroxy Vitamin D Levels in Patients With Vitiligo Vulgaris

Silverberg JI, Silverberg AI, Malka E, Silverberg NB
J Am Acad Dermatol. 2010;62:937-941

Study Summary

Recently, much has been made of the complex role that vitamin D plays in health maintenance. In addition to vitamin D's crucial role in calcium homeostasis, deficiencies have been linked to a growing list of pathologic states, including malignancy, cardiac disease, psychiatric illness, and autoimmune disorders -- such as diabetes mellitus, systemic lupus erythematosus, and multiple sclerosis.[1,2] In a small prospective cohort study, Silverberg and associates reported an association between low serum levels of vitamin D and the autoimmune skin disorder vitiligo.

Over a 1-year period, the investigators checked the serum 25-hydroxyvitamin D (25[OH]D) levels in 45 consecutive patients who presented with primarily generalized vitiligo (95.6% generalized, 4.4% segmental; 42.2% with > 6% body surface area involved). Over 60% of these patients had their vitamin D levels checked during the summer, and investigators noted no seasonal variation in serum 25(OH)D concentrations. In addition, vitamin D levels did not vary with age, sex, ethnicity, body surface area affected by vitiligo, or family history of vitiligo or other autoimmune disorders.

Similar to previous studies, Silverberg and colleagues found that higher Fitzpatrick skin phototypes correlated with lower serum 25(OH)D levels and a greater risk for vitamin D deficiency (< 30 ng/mL). In addition, the investigators noted the following:

  1. For every unit increase in Fitzpatrick skin type, the risk for 25(OH)D deficiency (serum levels < 30 ng/mL) increased by 1.76-fold;

  2. Patients with very low 25(OH)D levels (< 15 ng/mL) had a 10-fold higher risk of having another autoimmune disease, including systemic lupus erythematosus, Sjögren's syndrome, Hashimoto's thyroiditis, Graves' disease, alopecia areata, or inflammatory bowel disease; and

  3. No correlation was observed between serum vitamin D levels and vitiligo severity (body surface area, time of onset, or duration of disease).

Viewpoint

Vitamin D plays an essential role in calcium homeostasis, with deficiency leading to skeletal abnormalities, such as osteopenia and rickets. Recently, vitamin D deficiency has also been linked to a wide range of autoimmune disorders, including multiple sclerosis, systemic lupus erythematosus, rheumatoid arthritis, and inflammatory bowel disease.[3,4]

Silverberg and colleagues found that patients with vitiligo and very low 25(OH)D levels (< 15 ng/mL) were 10 times more likely to have a comorbid autoimmune disorder, such as systemic lupus erythematosus, inflammatory bowel disease, or Hashimoto's thyroiditis. Silverberg and colleagues therefore suggest that checking vitamin D levels in patients with vitiligo may identify a subset of patients at greater risk of having additional autoimmune disorders. However, does vitamin D deficiency contribute to autoimmunity, or are low levels merely a consequence of inflammatory disease?

Although we don't know the answer to this question yet, some intriguing clues have been noted. Vitamin D and its metabolites are known to exert complex immunomodulatory effects; for instance, 1,25(OH)2D3 inhibits the maturation and differentiation of dendritic cells, which are antigen-presenting cells that play an important role in the pathogenesis of some autoimmune diseases.[4] At present though, any causal link between vitamin D deficiency and autoimmune diseases such as vitiligo remains theoretical.

Abstract

Comments

3090D553-9492-4563-8681-AD288FA52ACE

processing....