Rationale:

• Waist circumference has a good correlation with visceral fat and is the easiest anthropometric measure for making this estimate.
• Increased waist circumference is associated with increased risk of disease.

Evidence:

• The waist circumference measurement alone is as good as the waist circumference divided by the hip circumference or the sagittal diameter as a correlate with cardiovascular risk factors (137; 138) and diabetes (184).
• Increased central fat increases the risk of death (189; 294; 295; 296); cardiovascular disease (190; 204; 297); diabetes (298); and cancer of the breast, endometrium, prostate, colon, kidney, and gall bladder (206).
• Increased central fat is related to risk of hypertension (299) and dyslipidemia (high triglyceride level and low HDL cholesterol) (136; 235).
• People with normal BMI but large waist circumference have a 22% higher risk of mortality (294).
• Elevated waist circumference combined with elevated triglycerides is a strong predictor of cardiovascular disease in postmenopausal women (300).
• Waist-to-hip ratio, but not BMI, is predictive of incident chronic kidney disease (301).
• In older adults, higher waist circumference indicated higher mortality once risk attributable to BMI was accounted for (302).
• Optimal waist circumference may be lower in Asians (303).
• In adults aged 75 years or older, WHR is a better predictor of risk than BMI or waist circumference (125).
• The metabolic syndrome is a defined entity that is present when three of the five characteristics in the table Clinical Features of the Metabolic Syndrome are present (236).
• Metabolic syndrome predicts all-cause and cardiovascular disease mortality (304) and risk of diabetes (305; 306), and the higher the number of abnormal components, the greater the risk of diabetes (307). Elevated waist circumference plus elevated glucose and either elevated blood pressure or triglycerides were more highly significant predictors of mortality in a large French cohort than other combinations (308).

Comments:

• The optimal method for measuring central and visceral fat is with a CT or MRI cross-sectional cut at L-4/L-5, but this is costly.
• Sagittal diameter and waist circumference divided by hip circumference are alternative methods to waist circumference alone for estimating central fat.
• Waist-to-height ratio may be better than waist-to-hip ratio or BMI (309).