title: Nutritional vitamin D use in chronic kidney disease: a survey of pediatric nephrologists.
abstract: BACKGROUND
  Vitamin D deficiency may contribute to risk of cardiovascular disease, diabetes, and infections, in addition to known effects on mineral metabolism. Controversy remains regarding the use of nutritional vitamin D supplementation in chronic kidney disease (CKD), and the supplementation practices of pediatric nephrologists are unknown.
  
  
  METHODS
  An electronic survey containing eight vignettes was sent to physician members of the International Pediatric Nephrology Association in 2011 to identify physician and patient characteristics that influence nephrologists to supplement CKD patients with nutritional vitamin D. Vignettes contained patient characteristics including light vs dark skin, CKD stage, cause of renal disease, parathyroid hormone (PTH), and 25(OH) vitamin D levels. Multivariate logistic generalized estimating equation regression was used to identify predictors of supplementation.
  
  
  RESULTS
  Of 1,084 eligible physicians, 504 (46%) completed the survey. Supplementation was recommended in 73% of cases overall (ranging from 91% of those with vitamin D levels <10 ng/mL to 35% with levels >30). Greater CKD severity was associated with greater recommendation of supplementation, especially for patients with higher vitamin D levels (test for interaction p < 0.0001). PTH level above target for CKD stage was associated with greater recommendation to supplement in pre-dialysis CKD, but did not have an impact on recommendations in dialysis patients (test for interaction p < 0.0001). Skin color, cause of CKD, and albumin levels were not associated with supplementation recommendation.
  
  
  CONCLUSIONS
  Recommending nutritional vitamin D is common worldwide, driven by CKD stage and vitamin D and PTH levels. Future studies are needed to establish the risks and benefits of supplementation.
authors.affiliation: Department of Pediatrics, Children's Hospital of Philadelphia, 3535 Market Street, Room 868, Philadelphia, PA, USA.
authors.forename: Lindsay M
authors.initials: LM
authors.lastname: Griffin
authors.forename: Michelle R
authors.initials: MR
authors.lastname: Denburg
authors.forename: Justine
authors.initials: J
authors.lastname: Shults
authors.forename: Susan L
authors.initials: SL
authors.lastname: Furth
authors.forename: Isidro B
authors.initials: IB
authors.lastname: Salusky
authors.forename: Wenke
authors.initials: W
authors.lastname: Hwang
authors.forename: Mary B
authors.initials: MB
authors.lastname: Leonard
mesh_terms: D016001:Confidence Intervals; D019587:Dietary Supplements; D006801:Humans; D009398:Nephrology / Q000706:statistics & numerical data; D016017:Odds Ratio; D010281:Parathyroid Hormone / Q000097:blood; D010372:Pediatrics / Q000706:statistics & numerical data; D017410:Practice Guidelines as Topic; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data*; D051436:Renal Insufficiency, Chronic / Q000150:complications / Q000188:drug therapy*; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires; D014807:Vitamin D / Q000008:administration & dosage / Q000031:analogs & derivatives / Q000097:blood / Q000627:therapeutic use*; D014808:Vitamin D Deficiency / Q000097:blood / Q000150:complications / Q000188:drug therapy*
chemical_list: D010281:Parathyroid Hormone; D014807:Vitamin D; C104450:25-hydroxyvitamin D