title: Ergocalciferol versus Cholecalciferol for Nutritional Vitamin D Replacement in CKD.
abstract: OBJECTIVE
  Is cholecalciferol (D3) superior to ergocalciferol (D2) in treating nutritional vitamin D deficiency in chronic kidney disease (CKD)? The answer to this question has not been fully explored.
  
  
  METHODS
  A retrospective analysis of 57 patients with non-dialysis-requiring CKD was conducted to assess the relative effectiveness of D2 versus D3 replacement on circulating 25(OH)D levels. Levels of 25(OH) D were assessed at baseline, after attempted repletion with D2, and then after attempted repletion with D3. The relative paired differences of the drug treatment effects were tested using t-tests. Multiple regression modeling was used to determine the factors significantly associated with differential responsiveness to the drugs.
  
  
  RESULTS
  The mean (SEM) age was 66.4 ± 1.4 and mean eGFR was 40.5 ± 2.2 ml/min/1.73 m(2). The baseline 25(OH)D level was 15.3 ± 0.8 ng/ml. After standardizing to 100,000 units of drug, increases after cholecalciferol (2.7 ± 0.3 ng/ml) were more than twice as great as those from ergocalciferol (1.1 ± 0.3 ng/ml) (p < 0.0001). A sensitivity analysis, which pooled the results of an additional 109 individuals treated with ergocalciferol alone, revealed similar findings (standardized change 2.7 ± 0.3 vs. 1.6 ± 0.3 ng/ml, p = 0.0025). Factors associated with a superior response to cholecalciferol were lower baseline 25(OH) D level at the start of therapy (p = 0.015) and the interaction of sex and age (p = 0.0048), with younger females tending to benefit relatively more from cholecalciferol than older males did.
  
  
  CONCLUSIONS
  Cholecalciferol may be superior to ergocalciferol in treating nutritional vitamin D deficiency in non-dialysis CKD.
authors.affiliation: Gamma Medical Research, Inc., Edinburg, Tex., USA.
authors.forename: Roberto
authors.initials: R
authors.lastname: Mangoo-Karim
authors.forename: Juliana
authors.initials: J
authors.lastname: Da Silva Abreu
authors.forename: George P
authors.initials: GP
authors.lastname: Yanev
authors.forename: Ninfa N
authors.initials: NN
authors.lastname: Perez
authors.forename: Jason R
authors.initials: JR
authors.lastname: Stubbs
authors.forename: James B
authors.initials: JB
authors.lastname: Wetmore
mesh_terms: D000368:Aged; D002762:Cholecalciferol / Q000627:therapeutic use*; D004872:Ergocalciferols / Q000627:therapeutic use*; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007676:Kidney Failure, Chronic / Q000150:complications* / Q000503:physiopathology; D008297:Male; D014808:Vitamin D Deficiency / Q000150:complications / Q000188:drug therapy*
chemical_list: D004872:Ergocalciferols; D002762:Cholecalciferol