Prevalence of metabolic syndrome and associated risk factors in Brazilian schoolchildren.

OBJECTIVE To determine the prevalence of metabolic syndrome (MetS) in schoolchildren from 6 to 16 years old, while considering their socio-economic status and other potential risk factors. DESIGN A cross-sectional study was conducted between April and November of 2005 in a semi-rural city with a total population of 13,000 inhabitants. SETTING The study was conducted in Maracai city, located in the Brazilian state of Sao Paulo. SUBJECTS Schoolchildren (n 2170) of both genders, corresponding to approximately 82% of all Maracai schoolchildren, were evaluated for components of MetS, as defined by the National Cholesterol Education Program; reference values for children and adolescents were adjusted for age and sex. RESULTS Overall, MetS prevalence was 3.6% (95% CI 2.9, 4.5) and did not differ statistically between genders, skin colour, between children and adolescents. However, when we analysed groups of subjects by weight, MetS prevalence progressively increased from 0.3% (95% CI 0.1, 0.8) in normal-weight subjects to 10.7% (95% CI 7.4, 14.8) and 34.5% (95% CI 25.9, 43.9) in overweight and obese subjects, respectively (both P < 0.001 compared to normal-weight controls). When socio-economic classes were considered, 4.7% high-income students (95% CI 3.5, 6.2) had MetS, which was significantly greater than low-income students (2.7%; 95% CI 1.9, 3.9; P = 0.023). CONCLUSIONS MetS prevalence was high in overweight and obese schoolchildren and these risk factors were present during childhood and adolescence. Changes in lifestyle and alimentary safety should be encouraged to avoid future cardiovascular morbidity and type 2 diabetes mellitus.