Differences in Prevalence and Severity of Coronary Artery Disease by Three Metabolic Syndrome Definitions

Background: People with metabolic syndrome (MS) are at increased risk for cardiovascular disease-associated morbidity and all-cause mortality. However, predicting the severity of coronary artery disease (CAD) according to different MS definitions is controversial. This study explores the prevalence and severity of CAD according to different MS definitions, focusing on their predictive value. Methods: We enrolled 690 Taiwanese adults with CAD in this study. Coronary artery lesions were classified by the modified American Heart Association-American College of Cardiology grading system. MS was diagnosed in 3 groups of randomly assigned subjects according to World Health Organization (WHO), International Diabetes Federation (IDF), and revised Adult Treatment Panel III (rATP III) criteria. Results: More MS components and more severe CAD were identified in the WHO group. Prevalence of MS in the WHO, IDF, and rATP III groups was 33.9%, 47.4%, and 52.8%, respectively (P < 0.001). Mean lesion and culprit vessel numbers were slightly higher in WHO-group patients. The WHO group had more complex stenoses with type C classification than did the IDF and rATP III groups (32.7%, 26.3%, and 28.1%; P = 0.041) and significantly more calcified stenoses (21.5%, 16.2%, and 16.4%; P = 0.027). In a comparison of CAD severity by complex morphology lesions, the area under the receiver operating characteristic curve was higher in the WHO group (0.552; 95% confidence interval, 0.509-0.595; P = 0.019). Conclusion: Compared with IDF and rATP III definitions, the WHO definition of MS has superior predictive value of CAD severity in Taiwanese patients.