Metabolic Risk Varies According to Waist Circumference Measurement Site in Overweight Boys and Girls

Objectives To compare waist circumference (WC) values measured at 4 commonly recommended sites and examine the relationships between WC sites and markers of metabolic risk in a sample of overweight boys and girls referred for weight management. Study design Overweight (mean body mass index percentile, 98.7; SD, 1.0) children and adolescents (n = 73; 41 girls, 32 boys; mean age, 12.5 years; SD, 2.6 years) had WC measured at 4 sites: iliac crest (WC1), narrowest waist (WC2), midpoint between the floating rib and iliac crest (WC3), and umbilicus (WC4). Height, weight, fasting insulin level, glucose level, cholesterol level, and systolic and diastolic blood pressure were also measured. Results Overall, WC1 (108.5 cm; SD, 16.3 cm) was greater than WC2 (97.4 cm; SD, 13.6 cm; P <.003), and WC2 was smaller than WC3 (104.3 cm; SD, 15.3 cm; P =.02) and WC4 (108.7 cm; SD, 16.2 cm; P < .0003). With logistic regression, WC2 and WC3 were revealed to be more consistently associated with metabolic syndrome by using 3 different definitions. Conclusion In our sample, we observed differences in 4 commonly recommended WC measurement sites and found that all sites were not equivalently associated with metabolic risk. Our findings provide preliminary support suggesting that WC measured at the narrowest waist and midpoint between the floating rib and iliac crest may represent the measurement sites most closely associated with metabolic risk in overweight boys and girls. (J Pediatr 2010;156:247-52).