title: Vitamin D deficiency in alopecia areata.
abstract: BACKGROUND
  Alopecia areata (AA) is a T cell-mediated autoimmune disease that causes inflammation around anagen-stage hair follicles. Insufficient levels of vitamin D have been implicated in a variety of autoimmune diseases. Previous reports have described the effects of vitamin D on hair follicles.
  
  
  OBJECTIVE
  To evaluate the status of vitamin D in patients with AA, and the relationship between vitamin D levels and disease severity.
  
  
  METHODS
  A cross-sectional study of 86 patients with AA, 44 patients with vitiligo and 58 healthy controls was conducted. The serum vitamin D levels of the study group were determined by liquid chromatography/tandem mass spectrometry.
  
  
  RESULTS
  Serum 25-hydroxyvitamin D [25(OH)D] levels in patients with AA were significantly lower than those of the patients with vitiligo and the healthy controls (P = 0·001 and P < 0·001, respectively). The prevalence of 25(OH)D deficiency was significantly higher in patients with AA (91%) compared with patients with vitiligo (71%) and healthy controls (33%) (P = 0·003 and P < 0·001, respectively). Furthermore, a significant inverse correlation was found between disease severity and serum 25(OH)D level in patients with AA (r = -0·409; P < 0·001).
  
  
  CONCLUSIONS
  Deficient serum 25(OH)D levels are present in patients with AA and inversely correlate with disease severity. Accordingly, screening patients with AA for vitamin D deficiencies seems to be of value for the possibility of supplementing these patients with vitamin D.
authors.affiliation: Dermatology Department, Şişli Etfal Training and Research Hospital, Halaskargazi Cad., 34371, Şişli-Istanbul, Turkey.
authors.forename: A
authors.initials: A
authors.lastname: Aksu Cerman
authors.forename: S
authors.initials: S
authors.lastname: Sarikaya Solak
authors.forename: I
authors.initials: I
authors.lastname: Kivanc Altunay
mesh_terms: D000328:Adult; D017677:Age Distribution; D000506:Alopecia Areata / Q000097:blood / Q000209:etiology*; D002853:Chromatography, Liquid; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D017678:Sex Distribution; D053719:Tandem Mass Spectrometry; D014807:Vitamin D / Q000031:analogs & derivatives / Q000378:metabolism; D014808:Vitamin D Deficiency / Q000150:complications*; D014820:Vitiligo / Q000097:blood / Q000209:etiology
chemical_list: D014807:Vitamin D; C104450:25-hydroxyvitamin D