title: Obese children without comorbidities have impaired microvascular endothelial function.
abstract: OBJECTIVE
  The aim was to test acetylcholine-induced endothelium-dependent vasodilatation in obese children without comorbidities, compared with normal weight controls, and to analyse associations between vasodilatation and other potential risk factors.
  
  
  METHODS
  Endothelium-dependent vasodilatation was induced by transdermal iontophoresis of acetylcholine in 54 obese children (8.3-18.2 years old, 41% girls) and 44 normal weight controls (7.5-20.2 years old, 82% girls), and the subsequent change in perfusion was measured with laser Doppler flowmetry. In a subgroup of the obese children, associations between acetylcholine-induced vasodilatation and blood lipids, glucose/insulin metabolism, inflammation, 24-h ambulatory blood pressure (ABP), cardiovascular fitness and duration of obesity were evaluated.
  
  
  RESULTS
  We found a lower endothelium-dependent vasodilatory response to acetylcholine in the obese children than the controls (p < 0.001). The peak perfusion response was 33% lower in obese children (p = 0.001). There was a trend towards lower vasodilatation in obese children with higher levels of triglycerides (p = 0.07). Children with the shortest duration of obesity exhibited the lowest vasodilatation (p = 0.03). No associations were found between 24-h ABP, cardiovascular fitness, inflammation and glucose/insulin metabolism.
  
  
  CONCLUSIONS
  Obese children without comorbidities have significantly impaired microvascular endothelial function. The children who had been obese for a longer time seemed less affected.
authors.affiliation: Divisions of Pediatrics, Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden.
authors.forename: P
authors.initials: P
authors.lastname: Hedvall Kallerman
authors.forename: E
authors.initials: E
authors.lastname: Hagman
authors.forename: A-K
authors.initials: AK
authors.lastname: Edstedt Bonamy
authors.forename: H
authors.initials: H
authors.lastname: Zemack
authors.forename: C
authors.initials: C
authors.lastname: Marcus
authors.forename: M
authors.initials: M
authors.lastname: Norman
authors.forename: M
authors.initials: M
authors.lastname: Westerståhl
mesh_terms: D000109:Acetylcholine; D000293:Adolescent; D002648:Child; D004730:Endothelium, Vascular / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D055806:Microvessels / Q000503:physiopathology*; D009765:Obesity / Q000503:physiopathology*; D014664:Vasodilation / Q000187:drug effects / Q000502:physiology*; D014665:Vasodilator Agents
chemical_list: D014665:Vasodilator Agents; D000109:Acetylcholine
keywords: Cardiovascular risk; Childhood obesity; Doppler; Insulin; Lipids