title: Differences in insulin sensitivity and secretory capacity based on OGTT in subjects with impaired glucose regulation.
abstract: BACKGROUND
  This study examined whether defects in insulin secretion contribute to the development and progression of type 2 diabetes mellitus (T2DM).
  
  
  METHODS
  Plasma insulin and glucose were measured after a glucose tolerance test to calculate the insulinogenic index (IGI) and the HOMA-IR Homeostasis model assessment of insulin resistance in subjects with normal glucose tolerance (NGT), prediabetes (preDM, n = 49), and T2DM patients with disease duration < 1 year (n = 84), 1 approximately 5 years (n = 45), or > 5 years (n = 37). Plasma proinsulin and adiponectin levels were also measured as a parameter of insulin secretion and resistance.
  
  
  RESULTS
  The mean HOMA-IR increased and the adiponectin levels decreased relative to the deterioration of glucose tolerance in NGT and preDM subjects. However, differences in the HOMA-IR were not related to disease duration in T2DM subjects. The mean IGI was similar in NGT and preDM subjects, but there were significant deteriorations in IGI relative to the duration of diabetes.
  
  
  CONCLUSIONS
  Defects in both insulin sensitivity and insulin secretion contribute to T2DM, but decreased insulin secretion may be more important in the development and progression of T2DM.
authors.affiliation: Department of Endocrinology and Metabolism, Kyung Hee University School of Medicine, Seoul, Korea.
authors.forename: Sang Youl
authors.initials: SY
authors.lastname: Rhee
authors.forename: Mi Kwang
authors.initials: MK
authors.lastname: Kwon
authors.forename: Byong-Jo
authors.initials: BJ
authors.lastname: Park
authors.forename: Suk
authors.initials: S
authors.lastname: Chon
authors.forename: In-Kyung
authors.initials: IK
authors.lastname: Jeong
authors.forename: Seungjoon
authors.initials: S
authors.lastname: Oh
authors.forename: Kyu Jeung
authors.initials: KJ
authors.lastname: Ahn
authors.forename: Ho Yeon
authors.initials: HY
authors.lastname: Chung
authors.forename: Sung Woon
authors.initials: SW
authors.lastname: Kim
authors.forename: Jin-Woo
authors.initials: JW
authors.lastname: Kim
authors.forename: Young Seol
authors.initials: YS
authors.lastname: Kim
authors.forename: Jeong-Taek
authors.initials: JT
authors.lastname: Woo
mesh_terms: D003924:Diabetes Mellitus, Type 2 / Q000503:physiopathology*; D004196:Disease Outbreaks; D005260:Female; D005951:Glucose Tolerance Test; D006305:Health Status Indicators; D006801:Humans; D007328:Insulin / Q000378:metabolism*; D007333:Insulin Resistance; D000078790:Insulin Secretion; D008297:Male; D008875:Middle Aged
chemical_list: D007328:Insulin