Association Between Waist Circumference and Percentage Body Fat among Rural Thais
Chatlert Pongchaiyakul MD*, Choowong Pongchaiyakul BSc**, Ekgaluck Wanothayaroj MD*, Tuan V Nguyen PhD***, Rajata Rajatanavin MD****
Affiliation : * Division of Endocrinology and Metabolism, Department of Medicine, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand ** Division of Nursing, Srinagarind Hospital, Khon Kaen University, Khon Kaen, Thailand *** Garvan Institute of Medical Research, Faculty of Medicine, University of New South Wales, Sydney, Australia ****Division of Endocrinology, Department of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
Objective : Determine the association between waist circumference (WC) and percentage body fat (%BF) and
to develop cut-off values and evaluate the accuracy of WC in the definition of obesity in rural Thai population.
Materials and Methods : A cross-sectional, epidemiologic study in 181 men and 255 women aged 50 + 16 yr
(mean + SD; range: 20-84 yr) sampled by stratified clustering sampling method, was designed. Percentage
body fat was measured by dual energy X-ray absorptiometry (GE Lunar Corp, Madison, WI). The “golden
standard” for defining obesity was%BF > 25 in men and%BF > 35 in women. Waist circumference in centime-
ter was measured.
Results : In this study, the %BF-based prevalence of obesity in men and women was 8.3% and 44%, respec-
tively. However, using the WC cut-off (WHO) of 102 cm in men and 88 cm in women, only 1.7% of men and 24%
of women were classified as obese. WC was a significant predictor of %BF, such that in men, a WC of 93 cm
would predict a %BF of 25%, and in women a WC of 84 cm would correspond to a %BF of 35%. The area under
the receiver operating characteristic curve was 0.87 and 0.88 in men and women, respectively. In conclusion,
waist circumference is a reasonably useful indicator of obesity.
Conclusion : The cut-off values of WC for diagnosing obesity should be lower in Thailand than in Western
countries.
Keywords : Obesity, Waist circumference, Percentage body fat, Rural, Thailand
