title: A randomized controlled trial of vitamin D replacement strategies in pediatric CF patients.
abstract: BACKGROUND
  Vitamin D insufficiency is common in children with cystic fibrosis (CF), yet data are sparse regarding the most effective form of vitamin D supplementation. The aim of this study was to compare two different vitamin D replacement regimens.
  
  
  METHODS
  We conducted a randomized controlled trial comparing 50,000 IU of ergocalciferol (vitamin D2) twice weekly for 8 weeks versus 50,000 IU of cholecalciferol (vitamin D3) weekly in patients with CF, pancreatic insufficiency, age 6-21 years and a 25(OH)D<30 ng/mL. The primary outcome was change in serum 25(OH)D concentration. For secondary analyses, we examined changes in IgG, IgE and CRP in patients who normalized their vitamin D levels.
  
  
  RESULTS
  A total of 47 patients completed the trial. The mean pre-treatment 25(OH)D concentration was 23.1 (SD 4.7) ng/mL. The overall mean increase in 25(OH)D was 11.1 (11.9) ng/mL and 31/47 (66%) achieved a 25(OH)D concentration ≥ 30 ng/mL; of the 26 participants who received D2, 18 (69%) achieved sufficiency while 13/21 (62%) participants treated with D3 achieved sufficiency. There was no difference between groups in change of 25(OH)D (p=0.65). Similarly, there was no difference in the number of patients to achieve vitamin D sufficiency between treatments (p=0.6).
  
  
  CONCLUSIONS
  Ergocalciferol administered as 50,000 IU twice weekly is as effective as cholecalciferol 50,000 IU weekly for 8 weeks in pediatric patients with CF and vitamin D insufficiency. Only 66% of the patients studied achieved the desired 25(OH)D concentration.
authors.affiliation: Boston Children's Hospital, Division of Respiratory Diseases, Harvard Medical School, 300 Longwood Ave, Boston, MA, United States. Electronic address: tsimoneau@connecticutchildrens.org.
authors.forename: Tregony
authors.initials: T
authors.lastname: Simoneau
authors.affiliation: Boston Children's Hospital, Division of Respiratory Diseases, Harvard Medical School, 300 Longwood Ave, Boston, MA, United States.
authors.forename: Gregory S
authors.initials: GS
authors.lastname: Sawicki
authors.affiliation: Clinical Research Center, Boston Children's Hospital, Boston, MA, United States.
authors.forename: Carly E
authors.initials: CE
authors.lastname: Milliren
authors.affiliation: Clinical Research Center, Boston Children's Hospital, Boston, MA, United States.
authors.forename: Henry A
authors.initials: HA
authors.lastname: Feldman
authors.affiliation: Hasbro Children's Hospital, Alpert Medical School of Brown University, Providence, RI, United States.
authors.forename: Catherine M
authors.initials: CM
authors.lastname: Gordon
mesh_terms: D000284:Administration, Oral; D000293:Adolescent; D015415:Biomarkers / Q000097:blood; D002648:Child; D002762:Cholecalciferol / Q000008:administration & dosage*; D003550:Cystic Fibrosis / Q000097:blood / Q000150:complications*; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D004359:Drug Therapy, Combination; D004872:Ergocalciferols / Q000008:administration & dosage*; D010188:Exocrine Pancreatic Insufficiency / Q000097:blood / Q000150:complications*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D016896:Treatment Outcome; D014807:Vitamin D / Q000031:analogs & derivatives / Q000097:blood; D014808:Vitamin D Deficiency / Q000097:blood / Q000188:drug therapy* / Q000209:etiology; D014815:Vitamins / Q000008:administration & dosage; D055815:Young Adult
chemical_list: D015415:Biomarkers; D004872:Ergocalciferols; D014815:Vitamins; D014807:Vitamin D; D002762:Cholecalciferol; C104450:25-hydroxyvitamin D
keywords: Bone health; Cystic fibrosis; Nutrition; Pediatric; Vitamin D