[Different prevalence of impaired glucose tolerance between hyperinsulinemic and normoinsulinemic subjects].
OBJECTIVE
To study the impact of different insulin levels on the conversion from impaired glucose tolerance (IGT) to type 2 diabetes mellitus (T2DM), through analysis of different glycometabolism condition among quinquagenarian population.


METHODS
Subjects enrolled were Beijing habitants who received annual physical examination [including oral glucose tolerance test (OGTT)] in the Chinese PLA General Hospital from 2005 - 2007. According to the OGTT results, the subjects were divided into three groups, including normal glucose tolerance-non-hyperinsulinemia group (NGT-NHIns), IGT-hyperinsulinemia group (IGT-HIns) and IGT-non-hyperinsulinemia group (IGT-NHINS). The prognosis between the year 2009 and 2010 of the three groups was observed. Hyperinsulinemia was diagnosed with fasting serum insulin ≥ 15 mU/L and/or 2-hour serum insulin ≥ 80 mU/L after glucose loading.


RESULTS
The rate of case number of conversion to T2DM in IGT-NHIns group (42/133) was higher than that in IGT-HIns group (24/154) or NGT-NHIns group (12/126). The HOMA insulin resistance index (HOMA-IR) of individuals with IGT-NHIns was lower than that of IGT-HIns [0.96 (0.40, 3.53) vs 2.04 (0.59, 23.20), P < 0.05], while whole body insulin sensitivity index (WBISI) was higher than that of IGT-HIns [7.48 (3.20, 31.35) vs 3.28 (0.86, 7.67), P < 0.05]. Modified β-cell function index (MBCI) and insulin secretion index (ISI) in IGT-NHIns was poorer than that of IGT-HIns respectively [2.57 (0.58, 10.98) vs 5.17 (1.04, 65.09); 7.66 (0.99, 28.40) vs 17.56 (4.18, 96.46), all P values < 0.01].


CONCLUSIONS
The risk of IGT-NHIns progressing into T2DM is higher than that of IGT-HIns. For the prevention of T2DM, individuals with IGT-NHIns should be paid more attention than keeping an eye on IGT-HIns patients. Early control of risk factors could protect β cell function and prevent the progression to T2DM.
Department of Geriatric Endocrinology, Chinese PLA General Hospital, Beijing 100853, China.
Jing
J
Xiao
Hui
H
Tian
Chun-lin
CL
Li
Wen-wen
WW
Zhong
Bo-ruo
BR
Sun
Yu-peng
YP
Li
Fu-sheng
FS
Fang
Xiao-fei
XF
Han
Yong-quan
YQ
Liu
Xiao-ling
XL
Cheng
D000368:Aged; D000369:Aged, 80 and over; D001786:Blood Glucose; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000175:diagnosis / Q000453:epidemiology; D005260:Female; D018149:Glucose Intolerance / Q000097:blood*; D005951:Glucose Tolerance Test; D006801:Humans; D006946:Hyperinsulinism / Q000097:blood* / Q000175:diagnosis / Q000453:epidemiology; D007328:Insulin / Q000097:blood*; D007333:Insulin Resistance; D007515:Islets of Langerhans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011379:Prognosis; D012307:Risk Factors
D001786:Blood Glucose; D007328:Insulin