title: 25-Hydroxyvitamin D concentrations in children with Crohn's disease supplemented with either 2000 or 400 IU daily for 6 months: a randomized controlled study.
abstract: OBJECTIVE
  To assess vitamin D status of pediatric patients with Crohn's disease (CD) and to compare their serum 25-hydroxyvitamin D (s-25OHD) with established cutoffs and assess whether 6 months of supplementation with 2000 IU/d, vs 400 IU/d, would reduce the group prevalence of vitamin D below these cutoffs.
  
  
  METHODS
  Subjects 8-18 years (n = 83) with quiescent CD were randomized to either 400 or 2000 IU vitamin D3/d for 6 months.
  
  
  RESULTS
  Baseline mean ± SD s-25OHD was 24 ± 8 ng/mL; 13 subjects (16%) had an s-25OHD <16 ng/mL, 27 (33%) < 20 ng/mL, and 65 (79%) < 30 ng/mL. There was no significant difference between groups in achieving the cutoffs of 16 ng/mL or 20 ng/mL at 6 months; however, only 35% of the 400 IU group achieved the greater cutoff of 30 ng/mL compared with 74% in the 2000 IU group (P < .001). Baseline adjusted mean s-25OHD concentrations at 6 months were 9.6 ng/mL (95% CI 6.0-13.2, P < .001) greater in the 2000 IU than the 400 IU group. Disease activity was not affected by supplement dose. Few subjects exceeded safety marker cutoffs, and this did not differ by dose.
  
  
  CONCLUSIONS
  At baseline, a high proportion of patients had a mean s-25OHD >20 ng/mL. 2000 IU vitamin D3/d is more effective in raising s-25OHD concentrations to > 30 ng/mL in children with CD than 400 IU/d, but both treatments were equally effective at achieving 16 or 20 ng/mL.
authors.affiliation: Food, Nutrition, and Health, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Kirstin E
authors.initials: KE
authors.lastname: Wingate
authors.affiliation: Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Kevan
authors.initials: K
authors.lastname: Jacobson
authors.affiliation: Department of Pediatrics, McMaster University, Hamilton, Ontario, Canada.
authors.forename: Robert
authors.initials: R
authors.lastname: Issenman
authors.affiliation: Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Matthew
authors.initials: M
authors.lastname: Carroll
authors.affiliation: Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Collin
authors.initials: C
authors.lastname: Barker
authors.affiliation: Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: David
authors.initials: D
authors.lastname: Israel
authors.affiliation: Department of Pediatrics, McMaster University, Hamilton, Ontario, Canada.
authors.forename: Herbert
authors.initials: H
authors.lastname: Brill
authors.affiliation: Dietetics and Human Nutrition, McGill University, Ste-Anne-de-Bellevue, Quebec, Canada.
authors.forename: Hope
authors.initials: H
authors.lastname: Weiler
authors.affiliation: Food, Nutrition, and Health, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Susan I
authors.initials: SI
authors.lastname: Barr
authors.affiliation: Food, Nutrition, and Health, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Wangyang
authors.initials: W
authors.lastname: Li
authors.affiliation: Canadian Center for Functional Medicine, Coquitlam, British Columbia, Canada.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Lyon
authors.affiliation: Food, Nutrition, and Health, University of British Columbia, Vancouver, British Columbia, Canada. Electronic address: tim.green@ubc.ca.
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Green
mesh_terms: D000293:Adolescent; D002648:Child; D003424:Crohn Disease / Q000097:blood*; D019587:Dietary Supplements; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D008297:Male; D013997:Time Factors; D014807:Vitamin D / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000097:blood
chemical_list: D014807:Vitamin D; C104450:25-hydroxyvitamin D