title: Vitamin D supplementation during rehabilitation in COPD: a secondary analysis of a randomized trial.
abstract: BACKGROUND
  Pulmonary rehabilitation is an important treatment for patients with Chronic Obstructive Pulmonary Disease, who are often vitamin D deficient. As vitamin D status is linked to skeletal muscle function, we aimed to explore if high dose vitamin D supplementation can improve the outcomes of rehabilitation in Chronic Obstructive Pulmonary Disease.
  
  
  METHODS
  This study is a post-hoc subgroup analysis of a larger randomized trial comparing a monthly dose of 100.000 IU of vitamin D with placebo to reduce exacerbations. 50 Subjects who followed a rehabilitation program during the trial are included in this analysis. We report changes from baseline in muscle strength and exercise performance between both study arms after 3 months of rehabilitation.
  
  
  RESULTS
  Vitamin D intervention resulted in significantly higher median vitamin D levels compared to placebo (51 [44-62] ng/ml vs 15 [13-30] ng/ml; p < 0.001). Patients receiving vitamin D had significantly larger improvements in inspiratory muscle strength (-11±12 cmH2O vs 0±14 cmH2O; p = 0.004) and maximal oxygen uptake (110±211 ml/min vs -20±187 ml/min; p = 0.029). Improvements in quadriceps strength (15±16 Nm) or six minutes walking distance (40±55 meter) were not significantly different from the effects in the placebo group (7±19 Nm and 11±74 meter; p>0.050).
  
  
  CONCLUSIONS
  High dose vitamin D supplementation during rehabilitation may have mild additional benefits to training.
authors.affiliation: Respiratory Division and Rehabilitation, Laboratory of Pneumology, University Hospital Gasthuisberg, KULeuven, Herestraat 49, Leuven, 3000, Belgium.
authors.forename: Miek
authors.initials: M
authors.lastname: Hornikx
authors.forename: Hans
authors.initials: H
authors.lastname: Van Remoortel
authors.forename: An
authors.initials: A
authors.lastname: Lehouck
authors.forename: Chantal
authors.initials: C
authors.lastname: Mathieu
authors.forename: Karen
authors.initials: K
authors.lastname: Maes
authors.forename: Ghislaine
authors.initials: G
authors.lastname: Gayan-Ramirez
authors.forename: Marc
authors.initials: M
authors.lastname: Decramer
authors.forename: Thierry
authors.initials: T
authors.lastname: Troosters
authors.forename: Wim
authors.initials: W
authors.lastname: Janssens
mesh_terms: D000368:Aged; D019587:Dietary Supplements; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D017079:Exercise Tolerance / Q000187:drug effects / Q000502:physiology; D005260:Female; D005541:Forced Expiratory Volume / Q000187:drug effects / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D053580:Muscle Strength / Q000187:drug effects / Q000502:physiology; D018482:Muscle, Skeletal / Q000187:drug effects / Q000503:physiopathology; D010101:Oxygen Consumption / Q000187:drug effects / Q000502:physiology; D029424:Pulmonary Disease, Chronic Obstructive / Q000503:physiopathology* / Q000534:rehabilitation*; D016896:Treatment Outcome; D014797:Vital Capacity / Q000187:drug effects / Q000502:physiology; D014807:Vitamin D / Q000008:administration & dosage* / Q000494:pharmacology / Q000627:therapeutic use*
chemical_list: D014807:Vitamin D