Background— The National Cholesterol Education Program (NCEP) recently proposed a simple definition for metabolic syndrome. Information on the prospective association of this definition for coronary heart disease (CHD) and type 2 diabetes is currently limited. Methods and Results— We used a modified NCEP definition with body mass index in place of waist circumference. Baseline assessments in the West of Scotland Coronary Prevention Study were available for 6447 men to predict CHD risk and for 5974 men to predict incident diabetes over 4.9 years of follow-up. Mean LDL cholesterol was similar but C-reactive protein was higher ( P <0.0001) in the 26% of men with the syndrome compared with those without. Metabolic syndrome increased the risk for a CHD event [univariate hazard ratio (HR)=1.76 (95% CI, 1.44 to 2.15)] and for diabetes [univariate HR=3.50 (95% CI 2.51 to 4.90)]. Metabolic syndrome continued to predict CHD events (HR=1.30, 95% CI, 1.00 to 1.67, P =0.045) in a multivariate model incorporating conventional risk factors. Men with 4 or 5 features of the syndrome had a 3.7-fold increase in risk for CHD and a 24.5-fold increase for diabetes compared with men with none (both P <0.0001). C-reactive protein enhanced prognostic information for both outcomes. With pravastatin, men with the syndrome had similar risk reduction for CHD as compared with those without (HR, 0.73 and 0.69; pravastatin versus placebo). Conclusions— A modified NCEP metabolic syndrome definition predicts CHD events, and, more strikingly, new-onset diabetes, and thus helps identify individuals who may receive particular benefit from lifestyle measures to prevent these diseases.

The prevalence of cardiometabolic multimorbidity (defined herein as a history of ≥2 of the following: diabetes mellitus, stroke, myocardial infarction [MI]) is increasing rapidly.^1-3 Considerable evidence exists about the mortality risk of having any 1 of these conditions alone.^4-7 However, evidence is sparse about life expectancy among people who have 2 or 3 cardiometabolic conditions concomitantly. Valid estimation of the associations of cardiometabolic multimorbidity with mortality requires comparison of people with multimorbidity with participants within the same cohorts who did not have any of the conditions at baseline. However, few population cohorts have had sufficient power, detail, and longevity to enable such comparisons.^8-14