Background: This study examines the contribution of the metabolic syndrome, as defined by National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III), to sub-clinical atherosclerosis and the cardiovascular risk assessment in an asymptomatic screening population.
Methods and results: We studied 1000 consecutive, asymptomatic, apparently healthy men and women aged 40-45 years, enrolled into a prospective cardiovascular risk assessment study. The 'metabolic score' (MS) was calculated as the sum of the five metabolic syndrome risk factors defined per NCEP III. The metabolic syndrome was defined as a metabolic score >/=3. Coronary artery calcification (CAC) on electron beam computed tomography (EBCT) was used to measure sub-clinical atherosclerosis. The prevalence of the metabolic syndrome was 8.9% (89/999), and was associated with significantly higher fasting serum insulin levels and significantly lower activity indices. Participants with the metabolic syndrome were more likely to have a positive CAC score 24.7% (24 of 89) compared to those without 16.5% (159 of 910, P<0.05.) After controlling for serum low-density lipoprotein, the metabolic score and the metabolic syndrome remained a significant independent predictor of sub-clinical atherosclerosis.
Conclusion: The 'metabolic score' is a simple clinical measurement that directly and independently relates to the likelihood of premature sub-clinical calcified atherosclerosis in an asymptomatic screening population.