title: Carotid extra-medial thickness in childhood: early life effects on the arterial adventitia.
abstract: OBJECTIVE
  Structural modification of the arterial adventitia may be an early event in atherosclerosis. Carotid extra-medial thickness is a new measure of arterial adventitial thickness. We examined the association of cardiovascular risk factors with extra-medial thickness, in childhood.
  
  
  METHODS
  Carotid extra-medial thickness was assessed by high-resolution ultrasound in 389 non-diabetic children aged 8-years. A non-fasting blood sample was collected from 314 participants. Associations of gender, age, lipoproteins, blood pressure, BMI z-score, waist:height ratio and parental history of early vascular disease, with extra-medial thickness were examined.
  
  
  RESULTS
  Carotid extra-medial thickness was lower in girls (r=-.163, P=.001) and directly associated with systolic (r=.128, P=.009), diastolic blood pressure (r=.130, P=.009), and height (r=.170, P=.0006). These associations remained after adjustment for carotid intima-media thickness. In multivariable analysis including carotid intima-media thickness, only gender and height were significantly associated with carotid extra-medial thickness. In gender-stratified analysis, the strongest associations with extra-medial thickness were BMI z-score (r=.181, P=.01), height (r=.210, P=.003) and diastolic blood pressure (r=.167, P=.02) for boys; and systolic blood pressure (r=.153, P=.03) and parental history of premature cardiovascular disease (r=.139, P=.05) for girls. The association of BMI z-score with extra-medial thickness differed by gender (P-interaction=.04).
  
  
  CONCLUSIONS
  Carotid extra-medial thickness is independently associated with gender and height in childhood. Extra-medial thickness may provide important information concerning early arterial health, particularly related to the arterial adventitia.
authors.affiliation: Boden Institute of Obesity, Nutrition, Exercise and Eating Disorders, University of Sydney, Australia. michael.skilton@sydney.edu.au
authors.forename: Michael R
authors.initials: MR
authors.lastname: Skilton
authors.forename: Tim R
authors.initials: TR
authors.lastname: Sullivan
authors.forename: Julian G
authors.initials: JG
authors.lastname: Ayer
authors.forename: Jason A
authors.initials: JA
authors.lastname: Harmer
authors.forename: Brett G
authors.initials: BG
authors.lastname: Toelle
authors.forename: Karen
authors.initials: K
authors.lastname: Webb
authors.forename: Guy B
authors.initials: GB
authors.lastname: Marks
authors.forename: David S
authors.initials: DS
authors.lastname: Celermajer
mesh_terms: D000367:Age Factors; D001794:Blood Pressure; D001827:Body Height; D015992:Body Mass Index; D002339:Carotid Arteries / Q000000981:diagnostic imaging*; D002340:Carotid Artery Diseases / Q000097:blood / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000503:physiopathology; D059168:Carotid Intima-Media Thickness; D002648:Child; D003238:Connective Tissue / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D016014:Linear Models; D008055:Lipids / Q000097:blood; D008297:Male; D015999:Multivariate Analysis; D009517:New South Wales / Q000453:epidemiology; D018570:Risk Assessment; D012307:Risk Factors; D055105:Waist Circumference
chemical_list: D008055:Lipids