title: Deficiency of serum concentration of 25-hydroxyvitamin D in psoriatic patients: a case-control study.
abstract: BACKGROUND
  Some autoimmune conditions have been associated with reduced vitamin D levels, including systemic lupus erythematosus, rheumatoid arthritis, diabetes mellitus, and multiple sclerosis.
  
  
  OBJECTIVE
  The main objective of this study was to analyze the 25-hydroxyvitamin D (OHD) status of patients with psoriasis in comparison with control subjects without this disease.
  
  
  METHODS
  This case-control study included 86 patients (43 with psoriasis and 43 age- and sex-matched control subjects) from the outpatient clinic of our hospital dermatology department in Granada, Spain. All patients and control subjects were studied during one 4-week period to avoid seasonal variations in vitamin D levels.
  
  
  RESULTS
  Serum 25-OHD levels were significantly lower in psoriatic patients than in control subjects even after adjusting for confounding factors in a multivariate analysis (odds ratio 2.89, 95% confidence interval 1.02-7.64, P < .03 for vitamin D insufficiency). Low 25-OHD levels were negatively associated with C-reactive protein (inflammatory activation marker) and body mass index in multiple linear regression analysis. Psoriatic patients with body mass index greater than or equal to 27 kg/m(2) had a higher risk of 25-OHD insufficiency (sensitivity of 82.3% and specificity of 51.7%).
  
  
  CONCLUSIONS
  Further studies with larger numbers of patients are required to analyze the pathogenic mechanisms underlying the relationship between 25-OHD deficiency and psoriasis.
  
  
  CONCLUSIONS
  The 25-OHD values are significantly lower in psoriatic patients than in control subjects. Low 25-OHD levels are negatively associated with C-reactive protein, an inflammatory activation marker, and with obesity. Psoriatic patients with a body mass index of 27 or more are likely to have vitamin D insufficiency.
authors.affiliation: Dermatology Department, San Cecilio University Hospital, Granada, Spain.
authors.forename: Jacinto
authors.initials: J
authors.lastname: Orgaz-Molina
authors.forename: Agustín
authors.initials: A
authors.lastname: Buendía-Eisman
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Arrabal-Polo
authors.forename: José Carlos
authors.initials: JC
authors.lastname: Ruiz
authors.forename: Salvador
authors.initials: S
authors.lastname: Arias-Santiago
mesh_terms: D000328:Adult; D015551:Autoimmunity; D015992:Body Mass Index; D002097:C-Reactive Protein / Q000032:analysis; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D006887:Hydroxycholecalciferols / Q000097:blood*; D016015:Logistic Models; D008297:Male; D015999:Multivariate Analysis; D009765:Obesity / Q000453:epidemiology; D011565:Psoriasis / Q000097:blood* / Q000453:epidemiology*; D012372:ROC Curve; D012680:Sensitivity and Specificity; D014808:Vitamin D Deficiency / Q000453:epidemiology*
chemical_list: D006887:Hydroxycholecalciferols; D002097:C-Reactive Protein