OBJECTIVETo compare and evaluate clinical applications of two definitions of metabolic syndrome in children and adolescents, which was developed by Pediatric Academy of Chinese Medical Association in 2012 (Chinese definition) and by International Diabetes Federation in 2007 (IDF definition), respectively.

METHODS593 obese children and adolescents aged 10 ≊16 y from July 2006 to December 2012 were enrolled in the study. The diagnostic concordance of two definitions for metabolic syndrome and individual components was estimated, and their sensitivity and specificity for detecting insulin resistance and early macrovascular complications were compared.

RESULTSThe concordance between two definitions for diagnosing metabolic syndrome was good (kappa=0.626); as for detecting the individual components, the Kappa concordance index were 1.000, 0.803, 0.780, 0.734 and 0.594 for hypertriglyceridemia, hyperglycemia, cholesterol abnormality and hypertension, respectively. The incidence of insulin resistance and early macrovascular complications, detected by the two definitions, were both increased with increasing number of abnormal components. The sensitivity and specificity for detecting insulin resistance in children with metabolic syndrome were 54.5% and 65.7% by Chinese definition, and 36.1% and 83.1% by IDF definition; while the sensitivity and specificity for detecting early macrovascular complications were 58.3% and 55.8% by Chinese definition, and 37.3% and 70.8% by IDF definition. After adjusting for age and sex, compared to the obese children and adolescents without metabolic syndrome, the odds ratios of insulin resistance and early macrovascular complications were 2.166 (P<0.001) and 1.771(P=0.008) for children with metabolic syndrome diagnosed by Chinese definition, and the odds ratio of insulin resistance and early macrovascular complications were 2.618 (P<0.001) and 1.357 (P=0.190) by IDF definition.

CONCLUSIONThe concordance between Chinese and IDF definitions for diagnosing metabolic syndrome in Chinese obese children and adolescents is good. Compared to IDF definition, Chinese definition is more sensitive for hypertension, hyperglycemia and hypercholesterolemia, thus it can more effectively detect insulin resistance and early macrovascular complication.