Comparison of definitions for the metabolic syndrome in adolescents. The HELENA study

Various definitions are used to define metabolic syndrome in adolescents. This study aimed to compare, in terms of prevalence and differences, five frequently used definitions for this population: International Diabetes Federation, National Cholesterol Education Program Adult Treatment Panel III (NCEP-ATP) modified by Cook, pediatric American Heart Association (AHA), World Health Organization, and Jolliffe and Janssen. A sample of 1004 adolescents (12.5-17.0 years) from the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) study was considered. The components of the definitions (waist circumference/BMI, plasma lipids, glycemia, and blood pressure) were applied, and definitions were compared by using crosstabs, sensitivity, specificity, and kappa coefficient. The prevalence of metabolic syndrome varied from 1.6 to 3.8% depending on the used definitions. Crosstabs comparing the definitions showed the fewest cases being misclassified (having metabolic syndrome or not) between NCEP-ATP and AHA. Analyses for kappa coefficient, sensitivity, and specificity confirmed this finding. Conclusion: The different definitions do not classify the same adolescents as having MS and prevalence varied between diagnostic methods. The modified NCEP-ATP and the AHA definitions were most analogous in defining subjects as having metabolic syndrome or not.