Ageing and blood pressure modulate the relationship between metabolic syndrome and aortic stiffness in never-treated essential hypertensive patients. A comparative study

OBJECTIVE: The aim of this study was to evaluate the impact of the metabolic syndrome (MS) and its components as defined by the National Cholesterol Education Program Adult Treatment Panel III on arterial stiffness in untreated hypertensive patients. METHODS: This was a cross sectional multi-center study performed in 46 healthcare centers, from 14 countries involved in the Complior study. Four hundred and forty patients (55% male) aged 18-73 years, with untreated essential hypertension were selected at inclusion. All patients underwent a full evaluation for all the risk factors representing the MS and an assessment of arterial stiffness using automatic measurement of carotid-femoral pulse wave velocity (PWV). RESULTS: In the overall population significant correlations were found, respectively, between PWV, MS (R=0.2, P<0.001) and gender (R=0.11, P=0.023) where PWV was higher in women. After adjustment for age and systolic blood pressure (SBP), analysis of covariance showed an independent effect of the MS on PWV, this effect increased with ageing and SBP especially after 47 years (age median, P=0.0047). Moreover, increase of mean PWV was highly associated with the number of MS factors in global population (P<0.001). These findings suggest that MS leads to early arterial wall ageing. CONCLUSIONS: Presence of MS induces an increase of arterial stiffness in untreated hypertensive patients independently from age and SBP. The increase of PWV is proportional to number of risk factors and affects principally patients after mid-age of 47 years where MS has ageing effects on arterial stiffness.