Association between waist circumference at two measurement sites and indicators of metabolic syndrome and cardiovascular disease among Thai adults

Abstract

Introduction: Waist circumference (WC) is a measure of central obesity, which is an established indicator of the risk of chronic disease. The objective of this study was to investigate the applicability of WC and risk of metabolic abnormality at two frequently used measurement sites in Thailand namely, at the umbilicus level (WC-U) and midway between the lowest rib and iliac crest (WC-M). Methods: Healthy adults aged 35-60 years living in Sung Noen District, Nakhon Ratchasima Province, Thailand were recruited by convenience for the study (N=296). WC was measured at two locations (WC-U and WC-M). Socioeconomic, health-habits, and physical-activity data were collected. Six ml blood samples from each participant were taken for analysis of glucose, lipids and C-reactive protein concentrations. Association between WC-U and WC-M was determined statistically. Results: WC measurements taken at WC-U and WC-M correlated strongly with each other in men (r=0.978, p<0.001), and in women (r=0.873, p<0.001). Both WC-U and WC-M correlated significantly with BMI, blood pressure, triglyceride, and cholesterol levels in both men and women. Intraclass correlation analysis confirmed highly significant associations between these two WC-measurement sites in men (ICC=0.960, p<0.001) and women (ICC=0.808, p<0.001). Conclusion: The results confirmed that both WC-U and WC-M can be used to monitor health status in men and women; however, WC-U is a simpler procedure for community health-risk surveillance and for self-monitoring.