[Prevalence of metabolic syndrome in adolescents: a systematic review]

The present study aimed to review the literature on the prevalence of metabolic syndrome and its components in adolescents (10-19 years old). The search was conducted in online databases (MEDLINE and SciELO), references from retrieved articles, and contacts with authors. Only original articles using either the criteria of the World Health Organization (WHO) or the National Cholesterol Education Program's Adult Treatment Panel III (NCEP ATP-III) were considered. Sixteen studies met the inclusion criteria. Eight studies were undertaken in low to medium-income countries, but none of them in Brazil. Prevalence of metabolic syndrome in studies using the NCEP-ATP III criteria ranged from 4.2% to 15.4%. Prevalence in studies using the WHO criteria was slightly higher: 4.5% to 38.7%. High triglyceride level was the most frequent component of the metabolic syndrome, with prevalence ranging from 4.9% to 75.0%, while high blood glucose showed the lowest prevalence. In conclusion, although there are few available studies, metabolic syndrome in adolescents is a highly prevalent health issue. The exact prevalence of metabolic syndrome in Brazilian adolescents is unknown.