Prevalence of metabolic syndrome among adolescents in a city in the Mediterranean area: comparison of two definitions

Background and objective: there are few studies on the prevalence of metabolic syndrome (MetS) in European adolescent populations, and some have reported a higher prevalence in the Mediterranean basin area. Our objective was to examine the prevalence of MetS in adolescents in a Mediterranean city of Spain, comparing two different definitions of MetS and the associated risk factors. Methods and results: a cross-sectional population-based study was conducted among 379 adolescents aged 12-16.9 years, selected using a random sampling method. Anthropometric measurements and fasting blood samples were obtained. The definitions of MetS used were that of the National Cholesterol Education Program's Adult Treatment Panel III (NCEP-ATPIII) and that of the International Diabetes Federation (IDF). Kappa coefficient was used to measure the agreement between definitions and a multivariate logistic regression model to determine the associated risk factors. Results: the prevalence of MetS was 5.7% (95%CI 3.33-8.07) according to the NCEP-ATPIII definition and 3.8% (95%CI 1.85-5.75) according to the IDF definition. No differences between the sexes or by age groups were found. The agreement between the two definitions was very good (kappa 0.815), especially in the obese subsample, but was lower in normal weight adolescents (kappa 0.497). Insulin resistance and obesity were associated with both definitions. Conclusions: the prevalence of MetS in our adolescent population is higher than the European media. Although the overall agreement between both definitions was very good, the prevalence was higher using the NCEP-ATPIII criteria. Independently of the definition used, obesity and insulin resistance were risk factors for MetS.