Carotid artery structure and function in patients with metabolic syndrome: could the current ATP III classification be further stratified?

Background: Metabolic syndrome (MS) is a major health problem and a strong predictor of cardiovascular disease. However, it is not well known whether a specific number of MS traits impacts in a different way on arterial structure and function. Purpose: To assess the relationship between different numbers ofMScriteria and carotid artery injury, in terms of stiffness and subclinical atherosclerosis. Methods: We evaluated 892 asymptomatic patients without history of coronary artery disease, referred to our Preventive Cardiology Department for a comprehensive risk factors screening. MS traits were defined according to the ATP III criteria. Common carotid intima-media thickness (IMT) was measured at 1 cm from bifurcation using ultrasound. Plaque was defined as focal thickening of the arterial wall . 1.4 mm. Carotid stiffness index (b)wasmeasured using ahigh-resolution echo-tracking system.Patients were divided into three groups according to the number of MS criteria: no MS (0, 1 or 2 traits, N=457), MS with 3 traits (MS3, N=231) and MS with 4 or 5 traits (MS4-5, N=204). Results: Mean age was 58+14 yrs (44.6% men). The differences between the 3 groups are shown in the table. Considering single MS traits separately, at multivariate analysis, age-corrected carotid IMT was independently correlated with hypertension (p=.02), impaired fasting plasma glucose (p=.008) and central obesity (p=.001). Age-corrected carotidb indexwasindependently correlated only with central obesity (p=.009).Thepresence of plaques was correlated with high levels of triglycerides (p=.011), hypertension (p,.001) and impaired fasting plasma glucose (p,.001). Conclusions: We observed a significantly worse impact of an increasing number of MS traits on carotid artery stiffness and atherosclerosis. Further studies are needed toevaluate if a new classification of MSaccording to the number of traits could stratify better the cardiovascular risk in these patients.