Background: Metabolic syndrome (MetS) is a cluster of risk factors, related to visceral adiposity, which is frequently observed in overweight patients. However, it has also been reported in normal weight subjects. Epicardial adipose tissue (EAT) is a visceral fat. The aim of the study was to evaluate whether EAT is associated with MetS in hypertensive patients with normal weight and waist.
Methods: We studied 174 Caucasian hypertensive patients, aged ≥40 years, with body mass index (BMI) <25 kg/m(2) and waist circumference <102 cm in men and 88 cm in women. MetS was defined according to NCEP ATP III criteria, not including waist circumference. EAT was measured by echocardiography above the free wall of the right ventricle, at end diastole.
Results: MetS was present in 21 (12%) patients. EAT was significantly higher in patients with MetS than in those without MetS, 4.0 ± 0.8 vs 2.5 ± 0.9 mm, P < 0.01, respectively, but BMI and waist circumference were not. Multivariate analysis showed that EAT was independently associated with MetS. Receiver operating characteristic (ROC) curve analysis showed that EAT significantly improved prediction of MetS when added to BMI and waist circumference. Indeed, the area under the curve improved from 0.63 (0.50-0.76) to 0.91 (0.87-0.96), and resulted significantly higher (P < 0.01). ROC curve for EAT alone indicated that the cutoff value of 3.1 mm had the best performance in predicting MetS, that is, 100% sensitivity and 79% specificity.
Conclusion: EAT thickness is associated with MetS in hypertensive patients with normal weight and waist.