The Insulin Resistance but Not the Insulin Secretion Parameters Have Changed in the Korean Population during the Last Decade.
BACKGROUND
This study aimed to compare the patterns of insulin secretion and resistance between Korean subjects in the 1990s and 2000s.


METHODS
Insulin secretion and resistance indices were calculated from subjects who underwent 75-g oral glucose tolerance tests in the year 1997 to 1999 and 2007 to 2011 at the Seoul St. Mary's Hospital, Korea.


RESULTS
A total of 578 subjects from the 1990s (mean age, 48.5 years) and 504 subjects from the 2000s (mean age, 50.2 years) were enrolled. Compared with the subjects from the 1990s, those from the 2000s exhibited increased insulin resistance (increased homeostatic model assessment for insulin resistance), and reduced insulin sensitivity (reduced Matsuda index and quantitative insulin sensitivity check index), regardless of their glucose tolerance status. However, insulinogenic index did not reveal significant differences between the 2 decades in subjects with or without diabetes. A distinct relationship was confirmed between Matsuda index and total area under the curve (insulin/glucose) in each glucose tolerance group. The mean product of the Matsuda index and the total area under the curve (insulin/glucose) as well as the oral disposition index, was lower in subjects with normal glucose tolerance from the 2000s than in those from the 1990s.


CONCLUSIONS
After rapid economic growth and changes in lifestyle patterns, insulin resistance has worsened across the glucose tolerance status; however, the insulin secretory function remained unchanged, which resulted in an increase in the susceptibility to the development of type 2 diabetes mellitus among Korean subjects without diabetes. We could not rule out the potential selection bias and therefore, further studies in general Korean population are needed.
Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Korea. ; Division of Endocrinology and Metabolism, Department of Internal Medicine, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.
Hae Kyung
HK
Yang
Catholic Institute of U-Healthcare, The Catholic University of Korea, Seoul, Korea.
Jin Hee
JH
Lee
Graduate School of Healthcare Management and Policy, The Catholic University of Korea, Seoul, Korea.
In-Young
IY
Choi
Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Korea. ; Division of Endocrinology and Metabolism, Department of Internal Medicine, Yeouido St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.
Hyuk Sang
HS
Kwon
Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Korea. ; Division of Endocrinology and Metabolism, Department of Internal Medicine, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.
Jeong Ah
JA
Shin
Clinical Research Coordinating Center, College of Medicine, The Catholic University of Korea, Seoul, Korea.
Seung Hee
SH
Jeong
Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Korea. ; Division of Endocrinology and Metabolism, Department of Internal Medicine, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.
Seung-Hwan
SH
Lee
Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Korea. ; Division of Endocrinology and Metabolism, Department of Internal Medicine, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.
Jae Hyoung
JH
Cho
Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Korea. ; Division of Endocrinology and Metabolism, Department of Internal Medicine, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.
Ho Young
HY
Son
Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Korea. ; Division of Endocrinology and Metabolism, Department of Internal Medicine, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.
Kun Ho
KH
Yoon
Diabetes mellitus; Insulin resistance; Insulin secretion; Korea; Oral glucose tolerance test