Revised Optimal Cut-Off Point of Waist Circumference for the Diagnosis of Metabolic Syndrome in Japanese Women and the Influence of Height

Abstract

Aim:We reevaluated waist circumference as a diagnostic criterion of metabolic syndrome (MetS) in Japanese. Methods: We enrolled 5,571 subjects (3,148 men and 2,423 women) who had health check-ups in our center. The criterion was reevaluated using the positive predictive value of a receiver-operating characteristics (ROC) curve at 10 different hypothesized lengths of waist circumference with or without a cluster of risk factors. We also drew ROC curves based on the atherosclerotic findings of clinical examinations. Results: Based on the ROC curves, the optimal waist circumference cut-off was 85 cm in men and 80 cm in women. Using this 80 cm cut-off point in women, misdiagnosis rates of MetS were lowered ( 19.1-56.6%) compared to the cut-off point currently in use. Integrating the influence of height, namely by using a waist-to-height 2 ratio, misdiagnosis rates in shorter populations were decreased in both men and women. Conclusion: These data suggested an optimal waist circumference cut-off to improve the diagnostic probability of MetS in Japanese women of 80 cm, as well as the utility of an easily detected anthropometric index such as a waist-to-height (cm 100/cm) or waist-to-height 2 (cm 10,000/cm 2 ) ratio, determined as 51 in men and 52 in women, or 30 in men and 33 in women, respectively. J Atheroscler Thromb, 2008; 15:94-99.Key words; Metabolic syndrome (MetS), Waist circumference, ROC curve, Height and 90 cm in women, accompanied by at least two of the following three risk factors: dyslipidemia, raised blood pressure, and raised fasting glucose. Although the cut-off point for waist circumference was defined by unique evidence corresponding to visceral fat area obtained by computed tomography (CT) scanning in Japanese subjects 9) , the optimal waist circumference cut-off has now become controversial. Because overt visceral fat obesity in Japanese is relatively low especially in women, waist circumference might lead to misdiagnosis, even when other risk factors are clustered. In fact, data obtained from 692 subjects in a community-based cohort study 10) and 329 subjects in a population-based study 11) in Japan indicate that a shorter waist circumference cut-off than those currently used would be optimal.

BMI, waist circumference, and clustering of cardiovascular risk factors in Japanese adults

“…Subjects on medication for hypertension, diabetes mellitus, or hypertriglyceridemia were classified as having these cardiovascular risk factors. This definition of clustering of cardiovascular risk factors has also been used in recent epidemiological studies [5][6][7][9][10][11][12][13].…”

“…Body mass index (BMI) is more widely used in clinical settings, but it does not provide information on fat distribution. Many investigators have reported an association between WC and clustering of cardiovascular risk factors and the optimal WC cutoff for the detection of clustering of cardiovascular risk factors in Japanese adults [4][5][6][7][8][9][10][11][12][13]. However, because of a strong positive correlation between BMI and WC, it appears to be difficult to completely discriminate the effects of BMI and WC, respectively, on clustering of cardiovascular risk factors.…”

A Strong Association between Lipid Accumulation Product and Diabetes Mellitus in Japanese Women and Men

“…It is of interest to know whether the difference in the cutoff value for waist circumference is reflected by the cutoff value for LAP. The cutoff value for waist circumference generally used to diagnose metabolic syndrome in Japan is 90 cm for women and 85 cm for men 1) ; however, there is criticism regarding the cutoff value for women, and much smaller cutoff values have been proposed as better cutoff values for diagnosing metabolic syndrome in Japanese women [15][16][17][18] . Using the above cutoff values for waist circumference (90 cm for women and 85 cm for men) and the cutoff value for triglycerides (150 mg/ dL [1.69 mM/L]), the cutoff values for LAP are calculated to be 54.2 for women and 33.9 for men, which are much higher and slightly lower, respectively, than the cutoff values proposed in the present study.…”

“…The present study, for the first time, reported the prevalence of a high LAP in the general population: approximately one-fourth of middle-aged Japanese women and men exhibited a high level of LAP, as defined using the proposed cutoff values. A racial difference has been shown in the relationship between insulin resistance and the ratio of triglycerides to HDL choThe cutoff value for waist circumference has been reported to be higher in Japanese men than in Japanese women [15][16][17][18] , which may reflect larger waist circumferences in men than in women. In the present study, the mean waist circumference was much larger in men than in women ( Table 1).…”

Waist Circumference and Cardiovascular Risk Factors in Japanese Men and Women

“…The appropriateness of the waist circumference cutoffs in Japan has been a matter of controversy particularly because the cutoff value is 5 cm lower in men than in women. Recent cross-sectional studies in Japan have consistently suggested that the optimal cutoff value for waist circumference is lower in women than in men [14][15][16][17][18][19][20] . In this study, we investigated the relationship between waist circumference and cardiovascular risk factors and attempted to determine optimal cut-off values for waist circumference in Japanese men and women.…”