title: Trace element supplementation in hemodialysis patients: a randomized controlled trial.
abstract: BACKGROUND
  People with kidney failure are often deficient in zinc and selenium, but little is known about the optimal way to correct such deficiency.
  
  
  METHODS
  We did a double-blind randomized trial evaluating the effects of zinc (Zn), selenium (Se) and vitamin E added to the standard oral renal vitamin supplement (B and C vitamins) among hemodialysis patients in Alberta, Canada. We evaluated the effect of two daily doses of the new supplement (medium dose: 50 mg Zn, 75 mcg Se, 250 IU vitamin E; low dose: 25 mg Zn, 50 mcg Se, 250 IU vitamin E) compared to the standard supplement on blood concentrations of Se and Zn at 90 days (primary outcome) and 180 days (secondary outcome) as well as safety outcomes.
  
  
  RESULTS
  We enrolled 150 participants. The proportion of participants with low zinc status (blood level <815 ug/L) did not differ between the control group and the two intervention groups at 90 days (control 23.9% vs combined intervention groups 23.9%, P > 0.99) or 180 days (18.6% vs 28.2%, P = 0.24). The proportion with low selenium status (blood level <121 ug/L) was similar for controls and the combined intervention groups at 90 days (32.6 vs 19.6%, P = 0.09) and 180 days (34.9% vs 23.5%, P = 0.17). There were no significant differences in the risk of adverse events between the groups.
  
  
  CONCLUSIONS
  Supplementation with low or medium doses of zinc and selenium did not correct low zinc or selenium status in hemodialysis patients. Future studies should consider higher doses of zinc (≥75 mg/d) and selenium (≥100 mcg/d) with the standard supplement.
  
  
  BACKGROUND
  Registered with ClinicalTrials.gov (NCT01473914).
authors.affiliation: Department of Medicine, University of Calgary, 3280 Hospital Dr NW, Calgary, AB, T2N 4Z6, Canada. tonelli.admin@ucalgary.ca.
authors.forename: Marcello
authors.initials: M
authors.lastname: Tonelli
authors.affiliation: Department of Medicine, University of Alberta, Edmonton, Canada. nwiebe@ualberta.ca.
authors.forename: Natasha
authors.initials: N
authors.lastname: Wiebe
authors.affiliation: Department of Medicine, University of Alberta, Edmonton, Canada. th11@ualberta.ca.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Thompson
authors.affiliation: Department of Physiology & Pharmacology, Calgary, Canada. dkinnibu@ucalgary.ca.
authors.forename: David
authors.initials: D
authors.lastname: Kinniburgh
authors.affiliation: Department of Medicine, University of Alberta, Edmonton, Canada. swk@ualberta.ca.
authors.forename: Scott W
authors.initials: SW
authors.lastname: Klarenbach
authors.affiliation: Department of Medicine, McMaster University, Hamilton, Canada. lastwalsh1975@gmail.com.|Population Health Research Institute, Hamilton Health Sciences/McMaster University, Hamilton, Canada. lastwalsh1975@gmail.com.|Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Canada. lastwalsh1975@gmail.com.
authors.forename: Michael
authors.initials: M
authors.lastname: Walsh
authors.affiliation: Department of Medicine, University of Alberta, Edmonton, Canada. aminu1@ualberta.ca.
authors.forename: Aminu K
authors.initials: AK
authors.lastname: Bello
authors.affiliation: Department of Medicine, University of Alberta, Edmonton, Canada. faruque@ualberta.ca.
authors.forename: Labib
authors.initials: L
authors.lastname: Faruque
authors.affiliation: Department of Agricultural, Food & Nutritional Science, University of Alberta, Edmonton, Canada. cjfield@ualberta.ca.
authors.forename: Catherine
authors.initials: C
authors.lastname: Field
authors.affiliation: Department of Medicine, University of Calgary, 3280 Hospital Dr NW, Calgary, AB, T2N 4Z6, Canada. Braden.Manns@albertahealthservices.ca.
authors.forename: Braden J
authors.initials: BJ
authors.lastname: Manns
authors.affiliation: Department of Medicine, University of Calgary, 3280 Hospital Dr NW, Calgary, AB, T2N 4Z6, Canada. Brenda.Hemmelgarn@albertahealthservices.ca.
authors.forename: Brenda R
authors.initials: BR
authors.lastname: Hemmelgarn
mesh_terms: D000368:Aged; D000416:Alberta; D001205:Ascorbic Acid / Q000627:therapeutic use; D001361:Avitaminosis / Q000150:complications / Q000188:drug therapy; D003677:Deficiency Diseases / Q000150:complications / Q000188:drug therapy*; D019587:Dietary Supplements; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000150:complications / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D006435:Renal Dialysis; D012643:Selenium / Q000008:administration & dosage*; D014131:Trace Elements / Q000008:administration & dosage*; D016896:Treatment Outcome; D014803:Vitamin B Complex / Q000627:therapeutic use; D014810:Vitamin E / Q000627:therapeutic use; D014815:Vitamins / Q000627:therapeutic use*; D015032:Zinc / Q000008:administration & dosage*
chemical_list: D014131:Trace Elements; D014815:Vitamins; D014803:Vitamin B Complex; D014810:Vitamin E; D012643:Selenium; D015032:Zinc; D001205:Ascorbic Acid