¹Obesity Research Group, Department of Family Medicine, National Taiwan University Hospital, Taipei, Taiwan

²Department of Family Medicine, China Medical College Hospital, Taichung, Taiwan

³Health Care Administration, Chia-Nan University of Pharmacy and Science, Taipei, Taiwan

⁴MJ Health Screening Center, Taipei, Taiwan

⁵Graduate Institute of Preventive & Medicine, National Taiwan University, Taipei, Taiwan

⁶Graduate Institute of Clinical Medicine, Taipei, Taiwan

Correspondence to: K-C Huang, Department of Family Medicine, National Taiwan University Hospital, 7 Chung-Shan South Road, Taipei, 100 Taiwan. E-mail: chin3@ha.mc.ntu.edu.tw

BACKGROUND: The increased health risks associated with obesity have been found to occur in Asians at lower body mass indices (BMIs). To determine the optimal cut-off values for overweight or obesity in Taiwan, we examined the relationships between four anthropometric indices and cardiovascular risk factors.

METHODS: The data were collected from four health-screening centers from 1998 to 2000 in Taiwan. Included were 55 563 subjects (26 359 men and 29 204 women, mean age=37.3±10.9 and 37.0±11.1 y, respectively). None had known major systemic diseases or were taking medication. Individual body weight, height, waist circumference (WC), and a series of tests related to cardiovascular risk (blood pressure, fasting plasma glucose, triglycerides, total cholesterol, low- and high-density lipoprotein cholesterol) were assessed and their relationships were examined. Receiver operating characteristic (ROC) analysis was used to find out the optimal cut-off values of various anthropometric indices to predict hypertension, diabetes mellitus and dyslipidemia.

RESULTS: Of the four anthropometric indices we studied, waist-to-height ratio (WHtR) in women was found to have the largest areas under the ROC curve (women=0.755, 95% CI 0.748-0.763) relative to at least one risk factor (ie hypertension or diabetes or dyslipidemia). The optimal cut-off values for overweight or obesity from our study in men and women showed that BMIs of 23.6 and 22.1 kg/m², WCs of 80.5 and 71.5 cm, waist-to-hip ratios (WHpR) of 0.85 and 0.76, and WHtR of 0.48 and 0.45, respectively, may be more appropriate in Taiwan.

CONCLUSIONS: WHtR may be a better indicator for screening overweight- or obesity-related CVD risk factors than the other three indexes (BMI, WC and WHpR) in Taiwan. Our study also supported the hypothesis that the cut-off values using BMI and WC to define obesity should be much lower in Taiwan than in Western countries.

International Journal of Obesity (2002) 26, 1232-1238. doi:10.1038/sj.ijo.0802040

obesity; ROC curve; cardiovascular risk factors; anthropometric indices; Taiwan