title: The effects of hyperuricaemia on flow-mediated and nitroglycerin-mediated dilatation in high-risk patients.
abstract: OBJECTIVE
  Uric acid is emerging as one of the newer risk markers to consider in the cardiovascular risk assessment because it is demonstrated to be associated with adverse cardiovascular outcomes, particularly in high cardiovascular risk patients. One of the proposed mechanisms involving hyperuricaemia is the development of vascular damage. The aim of this study is to examine the role of hyperuricaemia on vascular function in patients with high cardiovascular risk.
  
  
  RESULTS
  We examined the clinical significance of hyperuricaemia in relation to vasomotor response of the brachial artery by using high-resolution ultrasound in 304 subjects with coronary artery disease and/or diabetes. Nitroglycerin-mediated dilatation (NMD) was significantly lower in the hyperuricaemic group compared with the normouricaemic group (12.8 ± 6.9% vs. 16.2 ± 7.7%, p < 0.001), but no significant difference was observed in flow-mediated dilatation (FMD) between the two groups [3.78 (95% CR: 1.5-9.9) vs. 3.88 (95% CR: -2.6 to 9.9), p = 0.78]. Multivariate analysis demonstrated that smoking was the strongest predictor of FMD (b = -0.81, p = 0.02); and that smoking (b = -2.62, p = 0.003), SBP (b = -0.11, p = 0.001), hyperuricaemia (b = -2.11, p = 0.02) and use of nitrates (b = -3.30, p = 0.001) were independent predictors of NMD.
  
  
  CONCLUSIONS
  High cardiovascular risk patients with hyperuricaemia had a lower NMD than those with normouricaemia. Importantly, hyperuricaemia was independently associated with NMD after multivariable adjustments. To further understand the pathophysiological mechanisms involving hyperuricaemia, particularly in the context of impaired NMD, further experimental and clinical studies are needed.
authors.affiliation: Division of Cardiology, Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong.
authors.forename: C-K
authors.initials: CK
authors.lastname: Wong
authors.affiliation: Division of Cardiology, Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong.
authors.forename: Y
authors.initials: Y
authors.lastname: Chen
authors.affiliation: School of Public Health, The University of Hong Kong, Hong Kong.
authors.forename: L-M
authors.initials: LM
authors.lastname: Ho
authors.affiliation: Division of Cardiology, Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong.
authors.forename: Z
authors.initials: Z
authors.lastname: Zhen
authors.affiliation: Division of Cardiology, Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong; Research Centre of Heart, Brain, Hormone and Healthy Aging, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong.
authors.forename: C-W
authors.initials: CW
authors.lastname: Siu
authors.affiliation: Division of Cardiology, Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong; Research Centre of Heart, Brain, Hormone and Healthy Aging, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong. Electronic address: hftse@hku.hk.
authors.forename: H-F
authors.initials: HF
authors.lastname: Tse
authors.affiliation: Division of Cardiology, Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong; Research Centre of Heart, Brain, Hormone and Healthy Aging, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong. Electronic address: khkyiu@hku.hk.
authors.forename: K-H
authors.initials: KH
authors.lastname: Yiu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001916:Brachial Artery / Q000187:drug effects / Q000503:physiopathology; D002318:Cardiovascular Diseases / Q000188:drug therapy* / Q000503:physiopathology; D003430:Cross-Sectional Studies; D003920:Diabetes Mellitus / Q000503:physiopathology; D004730:Endothelium, Vascular / Q000503:physiopathology*; D005260:Female; D006801:Humans; D033461:Hyperuricemia / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D005996:Nitroglycerin / Q000494:pharmacology*; D012307:Risk Factors; D014665:Vasodilator Agents / Q000494:pharmacology*
chemical_list: D014665:Vasodilator Agents; D005996:Nitroglycerin
keywords: Endothelial function; Flow-mediated dilatation; Hyperuricaemia; Nitroglycerin-mediated dilatation; Uric acid; Vascular smooth muscle cells