The rapid rising prevalence of childhood obesity is related to increased risk of obesity-related diseases during adulthood. The aim of the present study was to review the data concerning the prevalence of metabolic syndrome (MS) in European children and adolescents (Part 1) and to determine and compare the prevalence of MS among overweight and obese children, and adolescents in five European countries using four MS definitions (Part 2). In total, 1 241 European obese children from five different countries (France: n =283, Greece: n =145, Italy: n =274, Poland: n =90, and Hungary: n =449) were studied for MS according to the definition of Ferranti et al., the World Health Organisation, the National Cholesterol Education Program and the International Diabetes Federation. We used age- and sex-specific cut-off values for the diagnosis of high blood pressure and increased waist circumference. The prevalence of MS was 35.7%, 31.4%, 20.3%, and 16.4%, respectively, according to the above-mentioned definitions. Only 6.3-8.8% of obese adolescents were free from any risk factors and the clustering of three risk factors or more was very high: 20.3-35.7% (depending on the type of definition). A total of 12.2% of children had MS and 55.8% were free from MS according to all four definitions.
Conclusions: The prevalence of MS is high among European obese children whatever criteria are used. There is an urgent need to achieve consensus concerning the definition of MS in adolescents and children.