Impact of the metabolic syndrome and its components on pulse wave velocity

Pulse wave velocity (PWV) reflects arterial stiffness and may provide an integrated index of vascular status and cardiovascular disease (CVD) risk. Although the individual components of the metabolic syndrome (MS) are well established cardiovascular risk factors, the impact of the MS and its components on PWV has not been well defined.

Using an automatic wave form analyzer, heart-femoral (hf) and brachial-ankle (ba) PWVs were measured simultaneously in 364 subjects (age, 44.8 +/- 9.3 years). None of the subjects had clinical atherosclerotic CVD, diabetes, or systemic disease. The association between PWVs and the features of the MS, individual and clustered, were analyzed.

By univariate analysis, the individual components of the MS, except for a low HDL-cholesterol level, were associated with increased hfPWV and baPWV. Hypercholesterolemia was also associated with increase in both PWVs. A low HDL-cholesterol level was associated with an increased baPWV. However, by multivariate analysis, none of the components of the MS, except for an elevated blood pressure (BP), was an independent factor affecting hfPWV and baPWV. After controlling for age and gender, hfPWV and baPWV were increased according to the number of MS components present (p < 0.001 for both). After controlling for age, gender and BP, the MS was associated with an increased baPWV (p < 0.05).

The clustering of MS components may interact to synergistically affect arterial stiffness, even though the individual MS components, except for an elevated BP, do not affect arterial stiffness independently.