Ohnishi et al. (1) applied International Diabetes Federation criteria of central obesity for Japanese patients (waist circumference ≥85 cm in men and ≥90 cm in women) in their study evaluating the relative importance of central and general obesity for incidence of type 2 diabetes in Japan. These International Diabetes Federation criteria of abdominal obesity were proposed by the Examination Committee of Criteria for “Obesity Disease” in Japan set up by the Japanese Society for the Study of Obesity (2) and are a result of the inappropriate presupposition that there are no sex differences in cut points of visceral fat area and that visceral fat area is linearly proportional to waist circumference, as mentioned previously (3). If they had determined the cut points of waist circumference by receiver-operating characteristic curves as they did to determine the cut points of BMI and visceral fat area and those of visceral fat area separately by sex, the cut points of waist circumference might have been different values. For example, Shiwaku et al. (4) reported that optimal cut points of waist circumference were 82 cm for men and 73 cm for women in Japanese, and Hara et al. (5) recently proposed 83–85 cm for men and 73–78 cm for women as optimal cut points of waist circumference for the diagnosis of metabolic syndrome in Japan. Sone et al. (6) recalculated the risk of metabolic syndrome for cardiovascular events in Japanese diabetic patients, applying Asian cut points for waist circumference (90 cm for men and 80 cm for women) instead of Japanese criteria (85 cm for men and 90 cm for women) and reached different results from their previous reports (7,8). Therefore, Ohnishi et al. should also reanalyze their data applying these proposed cut points by Hara et al. and Asian criteria of central obesity (≥90 cm in men and ≥80 cm in women) separately by sex before reaching conclusions on the relative prognostic importance of central and general obesity in Japan.

1.
Ohnishi H, Saitoh S, Takagi S, Katoh N, Chiba Y, Akasaka H, Nakamura Y, Shimamoto K: Incidence of type 2 diabetes in individuals with central obesity in a rural Japanese population: the Tanno and Sobetssu Study.
Diabetes Care
29
:
1128
–1129,
2006
2.
The Examination Committee of Criteria for “Obesity Disease” in Japan: New Criteria for “Obesity Disease” in Japan.
Circ J
66
:
987
–992,2002
3.
Oda E: Cut points of waist circumference (Letter).
Diabetes Care
29
:
1188
–1189,
2006
4.
Shiwaku K, Anuurad E, Enkhmaa B, Nogi A, Kitajima K, Yamasaki M, Yoneyama T, Oyunsuren T, Yamane Y: Predictive values of anthropometric measurements for multiple metabolic disorders in Asian populations.
Diabetes Res Clin Pract
69
:
52
–62,2005
5.
Hara K, Matsushita Y, Horikoshi M, Yoshiike N, Yokoyama T, Tanaka H, Kadowaki T: A proposal for the cutoff point of waist circumference for the diagnosis of metabolic syndrome in the Japanese population.
Diabetes Care
29
:
1123
–1124,
2006
6.
Sone H, Tanaka S, Ohashi Y: Cut points of waist circumference (Letter).
Diabetes Care
29
:
1189
,
2006
.
7.
Sone H, Mizuno S, Fujii H, Yoshimura Y, Yamasaki Y, Ishibashi S, Katayama S, Saito Y, Ito H, Ohashi Y, Akanuma Y, Yamada N, the Japan Diabetes Complications Study: Is the diagnosis of metabolic syndrome useful for predicting cardiovascular disease in Asian diabetic patients? Analysis from the Japan Diabetes Complications Study.
Diabetes Care
28
:
1463
–1471,2005
8.
Sone H, Tanaka S, Ishibashi S, Yamasaki Y, Oikawa S, Ito H, Saito Y, Ohashi Y, Akanuma Y, Yamada N, the Japan Diabetes Complications Study (JDCS) Group: The new worldwide definition of metabolic syndrome is not a better diagnostic predictor of cardiovascular disease in Japanese diabetic patients than the existing definitions: additional analysis from the Japan Diabetes Complications Study.
Diabetes Care
29
:
145
–147,
2006