[The association of central obesity with type 2 diabetes among Koreans according to the serum gamma-glutamyltransferase level: Korean genome and epidemiology study].
OBJECTIVE
This cross-sectional study was performed to examine if the serum gamma-glutamyltransferase (GGT) level that is within its normal range is associated with the risk of type 2 diabetes and if the association between the waist hip ratio (WHR) and type 2 diabetes is different depending on the serum GGT levels.


METHODS
The study subjects were 23,436 persons aged 40 years or older and who participated in regular health check-ups at 11 hospitals (males: 5,821, females: 17,615). The gender-specific quintiles of the serum GGT and WHR were used to examine the associations with type 2 diabetes.


RESULTS
The serum GGT levels within their normal range were positively associated with type 2 diabetes only in women. The adjusted odds ratios (ORs) were 1.0, 1.0, 1.4, 2.1, and 2.5 according to the quintiles of the serum GGT (p(trend)<0.01). The WHR was more strongly associated with the prevalence of diabetes among the women with a high-normal serum GGT level as compared with those with a low-normal serum GGT level (p for interaction=0.02). For example, the adjusted ORs for women with a low normal serum GGT level were 1.0, 1.2, 1.5, 2.2, and 2.4 according to the quintiles of the WHR, while those figures were 1.0, 2.4, 3.6, 5.0, and 8.3 among the women with a high normal serum GGT level. However, in men, the serum GGT was very weakly associated with type 2 diabetes and the association between the WHR and type 2 diabetes was not different depending on the serum GGT level.


CONCLUSIONS
Serum GGT within its normal range was positively associated with type 2 diabetes, and central obesity was more strongly associated with the prevalence of type 2 diabetes when the serum GGT level was high-normal. However, these associations were observed only in women, which is different from the previous findings. The stronger relation between central obesity and type 2 diabetes among women with a high-normal serum GGT level can be useful for selecting a group that is at high risk for type 2 diabetes irregardless of whatever the underlying mechanism is.
Shin
Ji-Yeon
JY
Department of Preventive Medicine, Kyungpook National University School of Medicine, Korea.
Hwang
Jun-Hyun
JH
Jeong
Jin-Young
JY
Kim
Sung-Hi
SH
Moon
Jai-Dong
JD
Roh
Sang-Chul
SC
Kim
Young-Wook
YW
Kim
Yangho
Y
Leem
Jong-Han
JH
Ju
Young-Su
YS
Hong
Young-Seoub
YS
Ha
Eun-Hee
EH
Lee
Yong-Hwan
YH
Lee
Duk-Hee
DH
Kim
Dong-Hyun
DH
D001786:Blood Glucose; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000201:enzymology / Q000453:epidemiology*; D016021:Epidemiologic Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D056128:Obesity, Abdominal / Q000453:epidemiology*; D016017:Odds Ratio; D015995:Prevalence; D056910:Republic of Korea / Q000453:epidemiology; D049629:Waist-Hip Ratio; D005723:gamma-Glutamyltransferase / Q000097:blood*
D001786:Blood Glucose; D005723:gamma-Glutamyltransferase