title: Peripheral wave reflection and endothelial function in untreated essential hypertensive patients with and without the metabolic syndrome.
abstract: OBJECTIVE
  Metabolic syndrome is associated with a high risk of cardiovascular disease in hypertension. We evaluated whether metabolic syndrome is associated with early vascular alterations, such as increased peripheral wave reflections and endothelial dysfunction, in untreated essential hypertensive patients.
  
  
  METHODS
  Augmentation index and pulse wave velocity were determined with applanation tonometry in 391 untreated hypertensive patients and 166 controls. Endothelium-dependent response was assessed as flow-mediated dilation of the brachial artery. Metabolic syndrome was defined according to the latest National Cholesterol Education Program Adult Treatment panel III.
  
  
  RESULTS
  Hypertensive patients showed significantly (P < 0.001) increased augmentation index and central pulse wave velocity, as well as reduced flow-mediated dilation, compared with controls. No further impairment in augmentation index or flow-mediated dilation was observed between patients with or without the metabolic syndrome components and with increasing number of metabolic syndrome. Age and systolic blood pressure, but no other single factor of the metabolic syndrome, resulted as significant predictors of augmentation index and flow-mediated dilation. Female gender was associated with increased augmentation index (P < 0.05) in the presence of the metabolic syndrome. Central pulse wave velocity was selectively impaired by metabolic syndrome in both genders. Finally, reactive hyperemia was reduced in patients with the metabolic syndrome and decreased significantly with the increasing number of metabolic syndrome.
  
  
  CONCLUSIONS
  In untreated hypertensive patients, the presence of metabolic syndrome, which selectively impairs central pulse wave velocity, does not account for a further deterioration of peripheral wave reflection and conduit artery endothelial function. Our results suggest that blood pressure, age and gender are important determinants of peripheral vascular structural and functional parameters in these subjects, irrespective of the metabolic syndrome.
authors.affiliation: Department of Internal Medicine, University of Pisa, Pisa, Italy.
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Plantinga
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Ghiadoni
authors.forename: Armando
authors.initials: A
authors.lastname: Magagna
authors.forename: Chiara
authors.initials: C
authors.lastname: Giannarelli
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Penno
authors.forename: Laura
authors.initials: L
authors.lastname: Pucci
authors.forename: Stefano
authors.initials: S
authors.lastname: Taddei
authors.forename: Stefano
authors.initials: S
authors.lastname: Del Prato
authors.forename: Antonio
authors.initials: A
authors.lastname: Salvetti
mesh_terms: D000328:Adult; D000368:Aged; D001916:Brachial Artery / Q000503:physiopathology*; D003430:Cross-Sectional Studies; D004548:Elasticity; D004730:Endothelium, Vascular / Q000503:physiopathology*; D005260:Female; D006801:Humans; D006973:Hypertension / Q000150:complications / Q000503:physiopathology*; D008297:Male; D024821:Metabolic Syndrome / Q000150:complications / Q000503:physiopathology*; D008875:Middle Aged; D011673:Pulsatile Flow / Q000502:physiology; D014664:Vasodilation / Q000502:physiology*