title: Folic acid improves endothelial function in children and adolescents with type 1 diabetes.
abstract: OBJECTIVE
  To evaluate the effect of folate supplementation on endothelial function in children and adolescents with type 1 diabetes.
  
  
  METHODS
  Thirty-six subjects with type 1 diabetes age 13.6+/-2.6 years completed a randomized, double-blind, placebo-controlled crossover trial. Each subject received 8 weeks of oral folic acid (5 mg/d) and 8 weeks of placebo, with an 8-week washout period. Before and after each intervention, we assessed endothelial function by using brachial artery responses to flow (flow-mediated dilatation [FMD]) and glyceryl trinitrate, von Willebrand factor, glucose, hemoglobin A1c, total plasma homocyst(e)ine (tHcy), vitamin B(12), serum folate, and red cell folate (RCF).
  
  
  RESULTS
  Folic acid increased FMD by 2.58 (3.1-5.7) % (95% confidence interval, 1.28-3.88), whereas placebo did not change FMD (-0.42%; 95% confidence interval, -1.67 to 0.83; P<.001). Folic acid increased serum folate by 14 nmol/L (6.2 ng/mL, P<.001) and RCF by 467.2 nmol/L (206 ng/mL, P<.001). Change in FMD was related to change in serum folate (r=0.46, P=.005) and RCF (r=0.39, P=.02). Glyceryl trinitrate responses, von Willebrand factor, tHcy, and hemoglobin A1c were not affected by the intervention.
  
  
  CONCLUSIONS
  Short-term high-dose folic acid improves endothelial function in children and adolescents with type 1 diabetes and normal folate status independently of tHcy.
authors.affiliation: Department of Endocrinology, University of Adelaide, Women's and Children's Hospital, 72 King William Road, North Adelaide, South Australia 5006, Australia. alexia.pena@adelaide.edu.au
authors.forename: Alexia Sophie
authors.initials: AS
authors.lastname: Peña
authors.forename: Esko
authors.initials: E
authors.lastname: Wiltshire
authors.forename: Roger
authors.initials: R
authors.lastname: Gent
authors.forename: Craig
authors.initials: C
authors.lastname: Hirte
authors.forename: Jennifer
authors.initials: J
authors.lastname: Couper
mesh_terms: D000284:Administration, Oral; D000293:Adolescent; D001783:Blood Flow Velocity / Q000502:physiology; D001916:Brachial Artery / Q000000981:diagnostic imaging; D018592:Cross-Over Studies; D003922:Diabetes Mellitus, Type 1 / Q000097:blood* / Q000503:physiopathology*; D004311:Double-Blind Method; D004730:Endothelium, Vascular / Q000187:drug effects*; D004912:Erythrocytes / Q000737:chemistry; D005260:Female; D005492:Folic Acid / Q000097:blood / Q000627:therapeutic use*; D006397:Hematinics / Q000097:blood / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D016896:Treatment Outcome; D014463:Ultrasonography
chemical_list: D006397:Hematinics; D005492:Folic Acid