Influence of waist circumference measurement site on the cardiometabolic risk factors in Korean adults

Background: Waist circumference (WC) has been recognized as a simple anthropometric measure of abdominal obesity and associated health risk. We compared WC values at five measurement sites, and examined whether measurement sites influence the relationships between WC and cardiometabolic risk in Korean adults. Methods: In this cross-sectional study, participants included 180 men and 176 women (age: 30-60 years, BMI: 18.5-30.0 kg/m(2)) who underwent a regular health examination between 2021 and 2022. WC was measured at the following sites; lowest rib, superior border of the iliac crest, midpoint between the lowest rib and the iliac crest, umbilicus, and narrowest waist. Fasting glucose and lipids, and resting blood pressure were measured after a 10-hour overnight fast. Cardiometabolic risk factors were defined using the modified National Cholesterol Education Program Adult Treatment Panel-III. Results: All WC measures at five sites were highly correlated (P < 0.01) with each other in men (r = 0.933-0.995) and women (r = 0.893-0.990). Differences in absolute mean WC values existed in both men and women. The prevalence of abdominal obesity (men: 17.2 %-34.4 %, women: 5.7 %-40.9 %) and metabolic syndrome (men: 30.6 %-38.9 % women: 13.6 %-22.2 %) varied depending on the measurement site. All five WC sites were similarly associated (P < 0.05) with an increased odd ratio for elevated glucose, elevated triglycerides, low HDL cholesterol and cardiometabolic risk clustering in men, and elevated blood pressure and cardiometabolic risk clustering in women. Conclusion: Although the differences in absolute WC values existed, the associations between WC at each site and cardiometabolic risk were similar in Korean adults.