title: 25-hydroxyvitamin D levels and vitamin D deficiency in children with rheumatologic disorders and controls.
abstract: OBJECTIVE
  To evaluate the prevalence of vitamin D deficiency, as well as factors associated with serum 25-hydroxyvitamin D [25(OH)D] levels, in children attending a pediatric rheumatology clinic, and to determine whether there was a difference in serum 25(OH)D levels and in vitamin D deficiency between children with autoimmune disorders and nonautoimmune conditions.
  
  
  METHODS
  Cross-sectional analysis of serum 25(OH)D levels of patients between the ages of 2 and 19 years, seen between November 2008 and October 2009.
  
  
  RESULTS
  A total of 254 patients were studied (169 autoimmune disorders, 85 nonautoimmune conditions). The mean age of study patients was 12.3 years; 67% were female and 80% were white. In the autoimmune disorders group, 23% had vitamin D deficiency [serum 25(OH)D < 20 ng/ml], and in the nonautoimmune conditions group 14% were vitamin D deficient. The average level of serum 25(OH)D was 28.6 (± 11) ng/ml (range 2 to 59). Age, ethnicity, body mass index, use of supplements, and season were significantly associated with serum levels of 25(OH)D (all p ≤ 0.02). The OR of patients with autoimmune disorders being vitamin D deficient was 2.3, in relation to patients with nonautoimmune conditions (p = 0.04).
  
  
  CONCLUSIONS
  Twenty percent of patients attending a pediatric rheumatology clinic were vitamin D deficient. Patients with autoimmune disorders were more likely to be vitamin D deficient than patients with nonautoimmune conditions. Screening of serum 25(OH)D levels should be performed for patients with autoimmune disorders.
authors.affiliation: Department of Pediatric Rheumatology, Floating Hospital for Children at Tufts Medical Center, Boston, Massachusetts, USA. cpelajo@tuftsmedicalcenter.org
authors.forename: Christina F
authors.initials: CF
authors.lastname: Pelajo
authors.forename: Jorge M
authors.initials: JM
authors.lastname: Lopez-Benitez
authors.forename: Laurie C
authors.initials: LC
authors.lastname: Miller
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D015897:Comorbidity / Q000639:trends; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D009765:Obesity / Q000097:blood / Q000453:epidemiology / Q000208:ethnology; D015995:Prevalence; D044469:Racial Groups; D012216:Rheumatic Diseases / Q000097:blood* / Q000453:epidemiology* / Q000208:ethnology; D017678:Sex Distribution; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000037:antagonists & inhibitors / Q000097:blood; D014808:Vitamin D Deficiency / Q000097:blood* / Q000453:epidemiology* / Q000208:ethnology
chemical_list: D014807:Vitamin D; C104450:25-hydroxyvitamin D