Introduction: The presence of Metabolic Syndrome (MetS) may be associated with increased cardiovascular risk. The International Diabetes Foundation (IDF) has recently published new diagnostic criteria for MetS. Thus, we sought to compare IDF-defined MetS, the previously defined Cholesterol Education Program Adult Treatment Panel III (ATPIII) and the European SCORE risk stratification model as predictors of the presence of Ischaemic Heart Disease (IHD) within an asymptomatic population.
Methods: participants (979 males, 376 females) underwent full cardiovascular assessment over a twelve month period, including detailed questionnaire, measurement of waist circumference, BMI calculation, sphygmomanometry, fasting glucose and lipid profiling and exercise stress testing (EST). The presence of MetS was defined in accordance with both the IDF and ATPIII definitions. Additionally, ten-year risk of having a fatal cardiovascular event was calculated on the basis of European SCORE risk stratification model.
Results: Overall, 320 (23.6%) and 187 (13.8) participants had IDF and ATPIII defined MetS respectively. Ischaemia on EST was evident for 220 (16.2%) subjects; 73 individuals with IDF-defined MetS as well as ischaemia on EST, while 43 had ATPIII MetS criteria and ischaemia on EST. Thus, IDF was more effective than ATPIII at identifying those with ischaemia on EST. Finally, a multiple linear regression model was fitted to determine whether independent associations exist between the presence of MetS, SCORE cardiovascular risk prediction model and ischaemia on EST. Both IDF-defined MetS and SCORE were independently associated with ischaemia on EST (P=0.02; P<0.0005 respectively).
Conclusion: The IDF definition is superior to ATPIII in predicting the presence of cardiac ischaemia in a healthy asymptomatic population. However, neither definition accurately reflects the overall burden of cardiac ischaemia in the population. Further refinement of the IDF definition is required to effectively reflect true prevalence of cardiac ischaemia.