title: Effects of vitamin D supplementation on markers of vascular function after myocardial infarction--a randomised controlled trial.
abstract: BACKGROUND
  Low vitamin D levels are common, and are associated with a higher incidence of future vascular events. We tested whether vitamin D supplementation could improve endothelial function and other markers of vascular function in patients with a history of myocardial infarction.
  
  
  METHODS
  Parallel group, placebo-controlled, double-blind randomised trial. Patients with a history of myocardial infarction were randomised to receive 100,000 units of oral vitamin D3 or placebo at baseline, 2 months and 4 months. Outcomes were measured at baseline, 2 and 6 months. Reactive hyperaemia index on fingertip plethysmography was the primary outcome. Secondary outcome measures included blood pressure, cholesterol, C-reactive protein, von Willebrand factor, tumour necrosis factor alpha, E-selectin, B-type natriuretic peptide, thrombomodulin and 25-hydroxyvitamin D levels.
  
  
  RESULTS
  75 patients were randomised, mean age 66 years. 74/75 (99%) completed 6 month follow-up. 25 hydroxyvitamin D levels increased in the intervention group relative to placebo (+13 vs +1 nmol/L, p=0.04). There was no between-group difference in change in reactive hyperaemia index between baseline and 6 months (-0.18 vs -0.07, p=0.40). Of the secondary outcomes, only C-reactive protein showed a significant decline in the intervention arm relative to placebo at 6 months (-1.3 vs 2.0mg/L, p=0.03). Systolic blood pressure (+1.4 vs +2.3 mmHg, p=0.79), diastolic blood pressure (+2.0 vs +0.8 mmHg, p=0.54) and total cholesterol (+0.26 vs +0.24 mmol/L, p=0.88) showed no between-group difference at 6 months.
  
  
  CONCLUSIONS
  Supplementation with vitamin D did not improve markers of vascular function in patients with a history of myocardial infarction.
authors.affiliation: Ageing and Health, University of Dundee, Ninewells Hospital, Dundee DD1 9SY, United Kingdom. m.witham@dundee.ac.uk
authors.forename: Miles D
authors.initials: MD
authors.lastname: Witham
authors.forename: Fiona J
authors.initials: FJ
authors.lastname: Dove
authors.forename: Faisel
authors.initials: F
authors.lastname: Khan
authors.forename: Chim C
authors.initials: CC
authors.lastname: Lang
authors.forename: Jill J F
authors.initials: JJ
authors.lastname: Belch
authors.forename: Allan D
authors.initials: AD
authors.lastname: Struthers
mesh_terms: D000368:Aged; D015415:Biomarkers / Q000097:blood; D001794:Blood Pressure / Q000187:drug effects / Q000502:physiology; D002784:Cholesterol / Q000097:blood; D019587:Dietary Supplements; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood* / Q000188:drug therapy*; D014807:Vitamin D / Q000494:pharmacology / Q000627:therapeutic use*
chemical_list: D015415:Biomarkers; D014807:Vitamin D; D002784:Cholesterol