The National Cholesterol Education Program - Adult Treatment Panel III, International Diabetes Federation, and World Health Organization definitions of the metabolic syndrome as predictors of incident cardiovascular disease and diabetes.

OBJECTIVE The clinical value of metabolic syndrome is uncertain. Thus, we examined cardiovascular disease (CVD) and diabetes risk prediction by the National Cholesterol Education Program (NCEP)-Adult Treatment Panel III (ATPIII), International Diabetes Federation, and World Health Organization definitions of the metabolic syndrome. RESEARCH DESIGN AND METHODS We analyzed the risks associated with metabolic syndrome, the NCEP multiple risk factor categories, and 2-h glucose values in the San Antonio Heart Study (n = 2,559; age range 25-64 years; 7.4 years of follow-up). RESULTS Both ATPIII metabolic syndrome plus age > or = 45 years (odds ratio 9.25 [95% CI 4.85-17.7]) and multiple (two or more) risk factors plus a 10-year coronary heart disease (CHD) risk of 10-20% (11.9 [6.00-23.6]) had similar CVD risk in men without CHD, as well as CHD risk equivalents. In women counterparts, multiple (two or more) risk factors plus a 10-year CHD risk of 10-20% was infrequent (10 of 1,254). However, either a 10-year CHD risk of 5-20% (7.72 [3.42-17.4]) or ATPIII metabolic syndrome plus age > or = 55 years (4.98 [2.08-12.0]) predicted CVD. ATPIII metabolic syndrome increased the area under the receiver operating characteristic curve of a model containing age, sex, ethnic origin, family history of diabetes, and 2-h and fasting glucose values (0.857 vs. 0.842, P = 0.013). All three metabolic syndrome definitions imparted similar CVD and diabetes risks. CONCLUSIONS Metabolic syndrome is associated with a significant CVD risk, particularly in men aged > or = 45 years and women aged > or = 55 years. The metabolic syndrome predicts diabetes beyond glucose intolerance alone.