title: Insulin secretion and insulin sensitivity on the oral glucose tolerance test (OGTT) in middle-aged Japanese.
abstract: The aim of this study was to assess the changes in insulin secretion and insulin sensitivity in relation to fasting and 2-hour plasma glucose (PG) levels and to assess the independent contributions of their impairments to non-diabetic hyperglycemia.  A total of 2157 Japanese workers (mean age 52.6±7.3 years and mean BMI 23.9±3.2 kg/m(2)) underwent an oral glucose tolerance test (OGTT).  Of these subjects, 1125 had normal glucose tolerance (NGT), 525 subjects had isolated impaired fasting glucose (IFG), 159 subjects had isolated impaired glucose tolerance (IGT), 263 subjects had combined IFG and IGT, and 85 subjects had newly diagnosed type 2 diabetes.  Insulinogenic index and Matsuda insulin sensitivity index (ISI) were significantly attenuated in subjects with normal but slightly elevated fasting PG, or in subjects with normal but slightly elevated 2-hour PG.  Whereas, InsAUC(120)/GluAUC(120) was not significantly decreased in those subjects, and significant decrease of it was observed exclusively in subjects with abnormal fasting PG (≥ 106 mg/dL) or abnormal 2-hour PG (≥ 221 mg/dL).  Using multiple regression analyses, both Matsuda ISI and insulinogenic index were independently correlated with PG concentrations in subjects with IFG and/or IGT, while Matsuda ISI alone was independently correlated with fasting PG concentrations in normoglycemic subjects.  In conclusion, both insulinogenic index and Matsuda ISI were significantly attenuated in subjects with normal but slightly elevated PG.   Lowering of Matsuda ISI was likely to be a strong contributor to 'elevation of fasting PG within the normal range' in this population.
authors: Department of Internal Medicine, Hokuriku Central Hospital, Toyama, Japan. ririoka@goo.jp
authors: Rie
authors: R
authors: Oka
authors: Kunimasa
authors: K
authors: Yagi
authors: Masaru
authors: M
authors: Sakurai
authors: Koshi
authors: K
authors: Nakamura
authors: Tadashi
authors: T
authors: Moriuchi
authors: Susumu
authors: S
authors: Miyamoto
authors: Atsushi
authors: A
authors: Nohara
authors: Masa-Aki
authors: MA
authors: Kawashiri
authors: Yoshiyu
authors: Y
authors: Takeda
authors: Masakazu
authors: M
authors: Yamagishi
mesh_terms: D000328:Adult; D000368:Aged; D000465:Algorithms; D001786:Blood Glucose / Q000032:analysis*; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000208:ethnology / Q000378:metabolism / Q000503:physiopathology; D005260:Female; D018149:Glucose Intolerance / Q000097:blood / Q000208:ethnology / Q000378:metabolism / Q000503:physiopathology; D005951:Glucose Tolerance Test; D006779:Hospitals, Public; D006801:Humans; D006943:Hyperglycemia / Q000097:blood / Q000208:ethnology / Q000378:metabolism / Q000503:physiopathology; D015994:Incidence; D007328:Insulin / Q000097:blood / Q000378:metabolism*; D007333:Insulin Resistance / Q000208:ethnology; D000078790:Insulin Secretion; D050417:Insulin-Secreting Cells / Q000378:metabolism*; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D012720:Severity of Illness Index
chemical_list: D001786:Blood Glucose; D007328:Insulin