A comparison of the new international diabetes federation definition of metabolic syndrome to WHO and NCEP definitions in Chinese, European and South Asian origin adults.

OBJECTIVES To compare the prevalence, agreement and phenotypic characteristics in three ethnic groups of the new International Diabetes Federation (IDF) definition of metabolic syndrome (MS) to the World Health Organization (WHO) and national cholesterol education program (NCEP) definitions. SETTING Newcastle upon Tyne, England. DESIGN Cross-sectional surveys. PARTICIPANTS Chinese (171 men and 185 women), European (257 men and 301 women), and South Asian (264 men and 295 women) adults, ages 25 to 64 years. MAIN OUTCOME MEASURES Anthropometric indices: blood pressure, fasting lipids, urine albumin-to-creatinine ratio, glucose intolerance, insulin resistance. RESULTS IDF-defined MS was highly prevalent in all groups, ranging from 12.3% (95% CIs 7.4-17.2) in Chinese men to 45.5% (39.5-51.5) in South Asian men. In women, of all ethnic groups, more than 80% of those with WHO- or NCEP-defined MS also had IDF-defined MS. In men, however, agreement was less good. For example, in each ethnic group, more than a third of those with WHO-defined MS did not have IDF-defined MS. Within each ethnic group, the biological characteristics of those with MS by any definition were largely the same. However, differences existed between ethnic groups. For example, in those with IDF-defined MS, both South Asian men and women had significantly (P < .05) higher insulin resistance and significantly lower systolic and diastolic blood pressure than Europeans or Chinese. CONCLUSIONS Agreement between the IDF and other definitions is better in women than men. The phenotype is similar within each ethnic group whatever the definition, but differs between groups suggesting that risks associated with MS differ by ethnic group.