The metabolic syndrome (MS) is a frequent cause of coronary artery disease (CAD), and recently the National Cholesterol Education Program Adult Treatment Panel III suggested its diagnosis in the presence of 3 to 5 quantitatively defined markers. Because the consequences of the MS are likely related to the number and diversity of markers, we studied the relation between the number of markers-the MS score-and the degree of abdominal obesity, risk factor profile, and severity of CAD. One thousand one hundred eight subjects of a mostly white population with symptoms of CAD (793 men and 315 women; 58.1 +/- 9.8 years of age) were divided into 6 groups based on their MS scores. A low high-density lipoprotein cholesterol level was the most frequently observed marker, followed by increased blood pressure, triglycerides, waist circumference, and fasting glucose. As the MS score increased so did abdominal obesity, parameters of "nontraditional" dyslipidemia with surrogate markers of dense low-density lipoprotein and high-density lipoprotein particles, blood pressure, fasting glucose, insulin, and the homeostatic model assessment insulin resistance index. Similarly, an increasing MS score was significantly related to more severe coronary angiographic alterations and higher frequencies of unstable angina, myocardial infarction, percutaneous coronary intervention, and coronary artery bypass grafting. Therefore, the MS score provides a clinically useful index of MS severity and the associated atherosclerotic risk factor profile. It also correlates with the angiographic severity of CAD and its clinical complications.