The metabolic syndrome (syndrome X, insulin resistance syndrome) consists of a constellation of metabolic abnormalities that confer increased risk of cardiovascular disease (CVD) and diabetes mellitus. Evolution of the criteria for the metabolic syndrome since the original definition by the World Health Organization in 1998 reflects growing clinical evidence and analysis by a variety of consensus conferences and professional organizations. The major features of the metabolic syndrome include central obesity, hypertriglyceridemia, low levels of high-density lipoprotein (HDL) cholesterol, hyperglycemia, and hypertension (Table 22-1).
TABLE 22-1NCEP:ATPIIIa 2001 AND HARMONIZING DEFINITION CRITERIA FOR THE METABOLIC SYNDROME |Favorite Table|Download (.pdf) TABLE 22-1 NCEP:ATPIIIa 2001 AND HARMONIZING DEFINITION CRITERIA FOR THE METABOLIC SYNDROME
|NCEP:ATPIII 2001 ||HARMONIZING DEFINITIONb |
Three or more of the following:
• Central obesity: waist circumference >102 cm (M), >88 cm (F)
• Hypertriglyceridemia: triglyceride level ≥150 mg/dL or specific medication
• Low HDLc cholesterol: <40 mg/dL and <50 mg/dL for men and women, respectively, or specific medication
• Hypertension: blood pressure ≥130 mmHg systolic or ≥85 mmHg diastolic or specific medication
• Fasting plasma glucose level ≥100 mg/dL or specific medication or previously diagnosed type 2 diabetes
Three of the following:
• Waist circumference (cm)
|Men ||Women ||Ethnicity |
|≥94 ||≥80 ||Europid, sub-Saharan African, Eastern and Middle Eastern |
|≥90 ||≥80 ||South Asian, Chinese, and ethnic South and Central American |
|≥85 ||≥90 ||Japanese |
• Fasting triglyceride level >150 mg/dL or specific medication
• HDL cholesterol level <40 mg/dL and <50 mg/dL for men and women, respectively, or specific medication
• Blood pressure >130 mm systolic or >85 mm diastolic or previous diagnosis or specific medication
• Fasting plasma glucose level ≥100 mg/dL (alternative indication: drug treatment of elevated glucose levels)
The most challenging feature of the metabolic syndrome to define is waist circumference. Intraabdominal circumference (visceral adipose tissue) is considered most strongly related to insulin resistance and risk of diabetes and CVD, and for any given waist circumference the distribution of adipose tissue between SC and visceral depots varies substantially. Thus, within and between populations, there is a lesser vs. greater risk at the same waist circumference. These differences in populations are reflected in the range of waist circumferences considered to confer risk in different geographic locations (Table 22-1).
The prevalence of the metabolic syndrome varies around the world, in part reflecting the age and ethnicity of the populations ...