Abstract

The metabolic syndrome (MS) has been characterized as a cluster of risk factors that includes dyslipidemia, hypertension, glucose intolerance and central obesity. This syndrome increases the risk of cardiovascular disease. Augmentation index (AIx), a composite of wave reflection form medium-sized muscular arteries is related to the development of coronary artery disease. The aim of this study is to examine the change on central aortic waveforms in subjects between patients with metabolic syndrome and normal subjects. Using the non-invasive technique of pulse wave analysis by applantation tonometry, we investigated central aortic waveforms in 45 patients with MS and 45 matched controls. The MS was defined by NCEP-ATP III criteria. Age did not differ between the two groups. AIx was significantly elevated in patinets with MS compared with controls (21.91 +/- 11.41% vs 18.14 +/- 11.07%; P < 0.01). Subendocardial viability ratio (SEVR) (158.09 +/- 28.69 vs 167.09 +/- 30.06; P < 0.01) was significantly decreased in patients with MS compared with controls. Only the fasting glucose (r = 0.317, P = 0.03) among the components of MS and age (r = 0.424, P = 0.004) had a positive correlation with AIx. AIx increased as the number of MS components increased. These results show that the MS increased systemic arterial stiffness. Age and fasting blood glucose are independent risk factors of arterial stiffness in MS. The individual MS components, except for fasting blood glucose, do not affect arterial stiffness independently. But the clustering of MS components might interact to synergistically affect arterial stiffness.

• Keywords: Arterial stiffness;Augmentation index;Metabolic syndrome;Pulse wave analysis