title: Cholecalciferol (vitamin D3) therapy and vitamin D insufficiency in patients with chronic kidney disease: a randomized controlled pilot study.
abstract: OBJECTIVE
  To investigate the efficacy of cholecalciferol (vitamin D3) in raising serum 25-hydroxyvitamin D (25[OH)]D) levels and reducing parathyroid hormone (PTH) levels in patients with chronic kidney disease (CKD).
  
  
  METHODS
  In this double-blind, randomized controlled pilot study, participants with CKD stage 3 and 4 (estimated glomerular filtration rate, 15-59 mL/min/1.73 m2), vitamin D insufficiency (serum 25[OH]D <30 ng/mL), and serum intact PTH levels >70 pg/mL were randomly assigned to receive either 50 000 IU of cholecalciferol or placebo once weekly for 12 weeks. Primary outcomes (25[OH]D and PTH levels) were measured at baseline, week 6, and week 12. Secondary outcomes (1,25-dihydroxvitamin D and bone turnover markers) were measured at baseline and week 12. Because of skewed data distribution, statistical analyses were performed on a logarithmic scale. The difference between the group means was exponentiated to provide the geometric mean ratio. A linear mixed model using an unstructured variance-covariance matrix was used to examine change in the primary and secondary outcomes over time.
  
  
  RESULTS
  Geometric mean serum 25(OH)D concentrations of the study groups were similar at baseline (P = .77). At week 6, a significant difference between the treatment and placebo groups was detected (P = .001); this difference was maintained at week 12 (P = .002). Among cholecalciferol-treated participants, serum 25(OH)D concentration increased on average from 17.3 ng/mL (95% confidence interval [CI], 11.8-25.2) at baseline to 49.4 ng/mL (95% CI, 33.9-72.0) at week 12. As-treated analysis indicated a trend toward lower PTH levels among cholecalciferol-treated participants (P = .07).
  
  
  CONCLUSIONS
  Weekly cholecalciferol supplementation appears to be an effective treatment to correct vitamin D status in patients with CKD.
authors.affiliation: Departments of Nutrition and Health Sciences, Emory University, Atlanta, Georgia 30322, USA.
authors.forename: Prakash
authors.initials: P
authors.lastname: Chandra
authors.forename: José Nilo G
authors.initials: JN
authors.lastname: Binongo
authors.forename: Thomas R
authors.initials: TR
authors.lastname: Ziegler
authors.forename: Lynn E
authors.initials: LE
authors.lastname: Schlanger
authors.forename: Wenli
authors.initials: W
authors.lastname: Wang
authors.forename: James T
authors.initials: JT
authors.lastname: Someren
authors.forename: Vin
authors.initials: V
authors.lastname: Tangpricha
mesh_terms: D000135:Acid Phosphatase / Q000097:blood; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000469:Alkaline Phosphatase / Q000097:blood; D002118:Calcium / Q000097:blood; D002762:Cholecalciferol / Q000627:therapeutic use*; D024042:Collagen Type I / Q000097:blood; D004311:Double-Blind Method; D006801:Humans; D007527:Isoenzymes / Q000097:blood; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood; D010455:Peptides / Q000097:blood; D010865:Pilot Projects; D010919:Placebos; D051436:Renal Insufficiency, Chronic / Q000097:blood / Q000150:complications / Q000188:drug therapy*; D000071681:Tartrate-Resistant Acid Phosphatase; D014807:Vitamin D / Q000097:blood; D014808:Vitamin D Deficiency / Q000097:blood / Q000188:drug therapy* / Q000209:etiology
chemical_list: D024042:Collagen Type I; D007527:Isoenzymes; D010281:Parathyroid Hormone; D010455:Peptides; D010919:Placebos; C052929:collagen type I trimeric cross-linked peptide; D014807:Vitamin D; D002762:Cholecalciferol; D000469:Alkaline Phosphatase; D000135:Acid Phosphatase; D000071681:Tartrate-Resistant Acid Phosphatase; D002118:Calcium