Appropriate waist circumference cutoff points for central obesity in Korean adults

https://doi.org/10.1016/j.diabres.2006.04.013Get rights and content

Abstract

Background

The International Diabetes Federation consensus recently proposed a new definition for the diagnosis of metabolic syndrome, incorporating ethnically specific waist circumference (WC) cutoff points.

Objective

We investigated the ethnically appropriate WC cutoff values for central obesity in Korean adults to predict increased risk of elevated triacylglycerol, reduced HDL cholesterol, elevated blood pressure, elevated fasting plasma glucose, or two or more of these factors.

Design

We used data from 6561 adults, aged 20–80 years, who participated in the Korean Health and Nutritional Examination Survey of 1998, a cross-sectional health survey of a nationally representative sample of Koreans.

Results

Based on the receiver operating characteristic curve analysis, the WC value for predicting metabolic risk factors in Koreans was about 85 cm for men and 80 cm for women. The odds ratio for the risk of two or more metabolic risk factors increased abruptly in men with WC  90 cm and women with WC  85 cm. The 80th percentile for WC in the Korean population was 90 cm for men and 86.5 cm for women. Thus, the appropriate WC cutoff point for central obesity in Koreans was determined to be 90 cm for men and 85 cm for women.

Conclusions

Based on our criteria, the prevalence of central obesity was 19.8% in Korean men and 24.5% in Korean women. These findings suggest the applicability of ethnically specific cutoff points for WC in assessing central obesity.

Introduction

Metabolic syndrome is closely related to increased cardiovascular morbidity and mortality [1]. In 2005, the International Diabetes Federation (IDF) in a global consensus statement formulated a new, clinically accessible, worldwide definition of metabolic syndrome [2] built on earlier definitions formulated by the World Health Organization (WHO) [3] and the National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel, ATP III) [4]. The IDF defined metabolic syndrome as central obesity plus two of the following four additional factors: elevated plasma triacylglycerol, reduced HDL cholesterol, elevated blood pressure, and elevated fasting plasma glucose [2].

A prominent feature of the IDF definition is that central obesity is an essential, not an optional, component of metabolic syndrome, with central obesity defined according to ethnically specific values of waist circumference (WC) [2]. The cutoff point for central obesity in the United States was defined as ≥102 cm for men and ≥88 cm for women [4], whereas, for Europeans, the cutoff was ≥94 cm for men and ≥80 cm for women [5]. Asians are more prone to obesity-related co-morbidities than Caucasians, even at lower BMI and/or smaller WC values [6], [7]. Therefore, cutoff values of ≥90 cm for men and ≥80 cm for women were adopted for South Asians and Chinese [8], and the Japanese used cutoff points of ≥85 cm for men and ≥90 cm for women [9].

Using the NCEP ATP III definition of central obesity [5] (men, >102 cm; women, >88 cm), the prevalence of central obesity in Korea was only 1.3% for men and 15.3% for women [10], whereas the prevalence of central obesity among US adults was 29.8% in men and 46.3% in women [11]. Using Asian-Pacific guidelines for central obesity [8] (men, >90 cm; women, >80 cm), the prevalence of central obesity in Korea was 19.5% in men and 39.0% in women [12]. These findings suggest the importance of applying ethnically appropriate cutoff values of WC for assessing central obesity. In agreement with the IDF proposal, the Committee on Metabolic Syndrome of the Korean Society for the Study of Obesity (KSSO) investigated the appropriate WC cutoff points for central obesity in Koreans.

Section snippets

Study population

The Korean Ministry of Health and Welfare conducted the Korean National Health and Nutrition Examination Survey of noninstitutionalized Korean civilians in 1998. A stratified, multistage probability sampling design was used, with selections made from sampling units based on geographic area, sex, and age groups using household registries. The staff conducted surveys in households and administered questionnaires, which included the demographic, socioeconomic, dietary, and medical history of each

Basic characteristics of the study subjects

The basic characteristics of the study subjects and the prevalence of metabolic risk factors are shown in Table 1. The mean age of all participants was 45.1 years, and the mean BMI was 23.2 kg/m2. The mean waist circumference was 82.8 cm in men and 78.6 cm in women. Almost 26% of men and 16% of women had >12 years of education. About 66% of the men and 7% of the women were smokers. Twenty-two percent of the men and 1% of the women consumed more than 30 g of alcohol per day.

Elevated triacylglycerol

Discussion

Since Reaven first suggested a definition of metabolic syndrome in 1988 [15], many diagnostic criteria have been established for metabolic syndrome, including those proposed by the WHO [3], NCEP ATP III [4], European Group for the Study of Insulin Resistance (EGIR) [5], American Association of Clinical Endocrinologists (AACE) [16], and IDF [2]. The pathophysiology of metabolic syndrome was focused primarily on insulin resistance and hyperinsulinemia, but the importance of metabolic risk factors

Acknowledgments

We thank the members of the Korea Institute for Health and Social Affairs, who conducted the national survey. HJY and HSP were involved in the conception and design of the study; SYL, DJK, SMK, JHH, and HSP performed data analysis; SRK, HSK, CBL, SJO, CYP, GJC, and DYK contributed to the interpretation of the data; SYL, DJK, and HSP drafted the manuscript.

References (29)

  • M. Deurenberg-Yap et al.

    Relationships between indices of obesity and its co-morbidities in multi-ethnic Singapore

    Int. J. Obes. Relat. Metab. Disord.

    (2001)
  • International Obesity Task Force. Asia–Pacific perspective: redefining obesity and its treatment. Western Pacific...
  • Examination Committee of Criteria for ‘Obesity Disease’ in Japan; Japan Society for the Study of Obesity. New criteria...
  • H.S. Park et al.

    The metabolic syndrome and associated lifestyle factors among South Korean adults

    Int. J. Epidemiol.

    (2004)
  • Cited by (678)

    View all citing articles on Scopus

    This study was supported by a grant from the Korean Society for the Study of Obesity 2005.

    View full text