Impact of metabolic syndrome traits on cardiovascular function: should the Adult Treatment Panel III definition be further stratified?

AIMS: The aims of the study were to evaluate whether a further classification of metabolic syndrome according to the number of traits (based on the Adult Treatment Panel III definition) could better explain the impact on cardiovascular remodeling and function, and to assess the role of single metabolic syndrome components in this regard. METHODS: We studied by echocardiography and carotid ultrasound 435 asymptomatic patients with metabolic syndrome. Patients with coronary artery disease or more than mild valvular heart disease were excluded. Carotid stiffness index (β) was measured using a high-resolution echo-tracking system. Patients with metabolic syndrome were divided into two groups: metabolic syndrome with three traits (Gr.1) and metabolic syndrome with four or five traits (Gr. 2). RESULTS: Patients in Gr. 2 had higher left ventricular mass index (P < 0.001), left ventricular end-diastolic volume index (P = 0.029), left atrial volume index (P = 0.002), E/e' ratio (P = 0.002), intima-media thickness (P = 0.031), and prevalence of plaques (P = 0.01) than patients in Gr. 1. Left ventricular ejection fraction was similar in both groups. The mean carotid β index tended to be higher in Gr. 2. Considering metabolic syndrome traits separately, in an age-corrected multivariate analysis, abdominal obesity was found to have the strongest association with cardiac structure and carotid artery atherosclerosis and stiffness. CONCLUSION: An increasing number of metabolic syndrome traits had a significantly worse impact on cardiac remodeling and function and carotid artery atherosclerosis. Abdominal obesity showed the strongest association with cardiac structure, carotid artery stiffness, and intima-media thickness. Prospective studies are needed to evaluate whether a new classification of metabolic syndrome using the number of traits could add prognostic information.