Clinical usefulness of the metabolic syndrome for the risk of coronary heart disease does not exceed the sum of its individual components in older men and women. The Three-City (3C) Study

OBJECTIVES: To investigate the respective associations and clinical usefulness of the metabolic syndrome (MetS) and its individual components to predict the risk of first coronary heart disease (CHD) events in elderly. DESIGN: The Three-City is a French prospective multisite community-based cohort. SETTING: Three large French cities: Bordeaux, Dijon and Montpellier. PARTICIPANTS: 7612 subjects aged 65 and over who were free of CHD at baseline. MAIN OUTCOME MEASURES: The MetS was defined by the 2005 National Cholesterol Education Program Adult Treatment Panel III criteria. RESULTS: During a median follow-up of 5.2 years, 275 first CHD events were adjudicated. The MetS was associated with increased risks of total (adjusted HR: 1.78; 95% CI 1.39 to 2.28), fatal (HR: 2.40; 95% CI 1.41 to 4.09) and non-fatal (HR: 1.64; 95% CI 1.24 to 2.17) CHD events. The association with total CHD was significant in women (HR: 2.56; 95% CI 1.75 to 3.75) but not in men (HR: 1.39; 95% CI 0.99 to 1.94; p for interaction=0.012). When in the same multivariable model, hyperglycemia and abdominal adiposity in women, hyperglycemia, lower HDL cholesterol and abdominal adiposity (inverse association) in men were the components significantly associated with CHD. The components of the MetS but not the MetS itself improved risk prediction beyond traditional risk factors (NRI= 9.35%, p<0;001). CONCLUSION: The MetS is a risk marker for CHD in community-dwelling elderly subjects but may not be useful for CHD risk prediction purposes compared to its individual components.