title: Effect of vitamin D3 on self-perceived fatigue: A double-blind randomized placebo-controlled trial.
abstract: BACKGROUND
  Vitamin D deficiency is frequent and has been associated with fatigue in uncontrolled trials.
  
  
  METHODS
  This is the first double-blind placebo-controlled clinical trial to investigate the efficacy of per os vitamin D3 (cholecalciferol) in treating fatigue among otherwise healthy persons with low serum 25-hydroxyvitamin D (25(OH)D) levels. We enrolled 120 individuals (mean age 29 ± 6 years, 53% women) presenting with fatigue and vitamin D deficiency (serum 25(OH)D < 20 μg/L). Participants were randomized to a single oral dose of 100,000 units of vitamin D or placebo. The primary endpoint was intra-individual change in the fatigue assessment scale (FAS) at 4 weeks after treatment.
  
  
  RESULTS
  The mean age of the participants was 29 ± 6 years, 53% were women. Mean FAS decreased significantly more in the vitamin D group (-3.3 ± 5.3; 95% confidence interval [CI] for change -14.1 to 4.1) compared with placebo (-0.8 ± 5.3; 95% CI for change -9.0 to 8.7); (P = 0.01). Amelioration of fatigue was reported more frequently in vitamin D than in placebo group (42 [72%] vs. 31 [50%]; P = 0.01; odds ratio [OR] 2.63, 95% CI for OR 1.23-5.62). Among all participants, improvement in fatigue score correlated with the rise in 25(OH)D level (R = -0.22, P = 0.02).
  
  
  CONCLUSIONS
  Vitamin D treatment significantly improved fatigue in otherwise healthy persons with vitamin D deficiency.This study was registered at the www.ClinicalTrials.gov Protocol ID NCT02022475.
authors.affiliation: Department of Internal Medicine Institute for Clinical Chemistry, University Hospital Zurich and University of Zurich Division of Endocrinology, Diabetology and Clinical Nutrition Department of Geriatrics, University Hospital Zurich, Zurich Department of Internal Medicine, Spital Linth, Uznach, Switzerland.
authors.forename: Albina
authors.initials: A
authors.lastname: Nowak
authors.forename: Lukas
authors.initials: L
authors.lastname: Boesch
authors.forename: Erik
authors.initials: E
authors.lastname: Andres
authors.forename: Edouard
authors.initials: E
authors.lastname: Battegay
authors.forename: Thorsten
authors.initials: T
authors.lastname: Hornemann
authors.forename: Christoph
authors.initials: C
authors.lastname: Schmid
authors.forename: Heike A
authors.initials: HA
authors.lastname: Bischoff-Ferrari
authors.forename: Paolo M
authors.initials: PM
authors.lastname: Suter
authors.forename: Pierre-Alexandre
authors.initials: PA
authors.lastname: Krayenbuehl
mesh_terms: D000284:Administration, Oral; D000328:Adult; D002762:Cholecalciferol / Q000008:administration & dosage / Q000627:therapeutic use*; D004311:Double-Blind Method; D005221:Fatigue / Q000188:drug therapy* / Q000209:etiology; D005260:Female; D006801:Humans; D008297:Male; D057566:Self Report; D014807:Vitamin D / Q000031:analogs & derivatives / Q000097:blood; D014808:Vitamin D Deficiency / Q000097:blood / Q000150:complications / Q000188:drug therapy*; D014815:Vitamins / Q000008:administration & dosage / Q000627:therapeutic use*; D055815:Young Adult
chemical_list: D014815:Vitamins; D014807:Vitamin D; D002762:Cholecalciferol; C104450:25-hydroxyvitamin D