Central obesity, as assessed by waist circumference, was agreed as essential (panel), because of the strength of the evidence linking waist circumference with cardiovascular disease and the other metabolic syndrome components, and the likelihood that central obesity is an early step in the aetiological cascade leading to full metabolic syndrome. The waist circumference cutoff selected was the same as that used by European Group for the Study of Insulin Resistance, and lower than the main Adult Treatment Panel III recommendations, because most available data suggest an increase in other cardiovascular disease risk factors in Europids (white people of European origin, regardless of where they live in the world) when the waist circumference rises above 94 cm in men and 80 cm in women. 1 Ethnic-specific waist circumference cutoffs have been incorporated into the definition (table), and have been based on available data linking waist circumference to other components of the metabolic syndrome in different populations. 12, 14, 15 The levels of the other variables were as described by Adult Treatment Panel III, except that the most recent diagnostic level from the American Diabetes Association for impaired fasting glucose (5· 6 mmol/L [100 mg/dL]) was used. 16 Although this new definition will still miss substantial numbers of people with impaired glucose tolerance (because an oral glucose-tolerance test is not required), it retains the simplicity of the instrument. The consensus group also recommended additional criteria that should be part of further research into metabolic syndrome, including: tomographic assessment of visceral adiposity and liver fat, biomarkers of adipose tissue (adiponectin, leptin), apolipoprotein B, LDL particle size, formal measurement of insulin resistance and an oral glucose-tolerance test, endothelial dysfunction, urinary albumin, inflammatory markers (C-reactive protein, tumour necrosis factor, interleukin 6), and thrombotic markers (plasminogen activator inhibitor type 1, fibrinogen). These factors should be combined with assessment of CVD outcome and development of diabetes so better predictors can be developed. Researchers and clinicians should use the new criteria for the identification of high-risk individuals and for research studies. Preventive measures are obviously needed in the people identified. Mounting evidence suggests that lifestyle modification with weight loss and increased physical activity will be beneficial, although specific studies in metabolic syndrome are needed. There

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