title: The influence of type 2 diabetes on serum GH and IGF-I levels in hospitalized Japanese patients.
abstract: Although serum insulin like growth factor type 1 (IGF-I) levels are negatively correlated with hemoglobin A1c (HbA1c) in patients with type 1 diabetes, this correlation is controversial in patients with type 2 diabetes mellitus (T2DM) because of the influence of multiple factors including insulin secretion and obesity. The aim of this study was to evaluate the influence of T2DM on serum growth hormone (GH) and IGF-I levels in Japanese patients, who exhibited relatively low BMI compared with white patients in the previous studies.
  
  
  
  We retrospectively analysed 315 consecutive Japanese hospitalized patients with T2DM. We analysed factors correlated with changes in serum IGF-I levels and those related to diabetes.
  
  
  
  The median HbA1c was 8.7% (7.4-10.2) and the median body mass index (BMI) was 26.2kg/m(2) (23.1-29.7), which was relatively low compared with the previous studies. Overall, no correlations was found between serum GH or IGF-I levels and fasting plasma glucose (FPG) or HbA1c; however, when stratified by FPG and HbA1c levels, serum IGF-I levels were significantly lower in patients with FPG≥200mg/dL than in those with FPG<200mg/dL (p=0.039). In addition, serum IGF-I levels were significantly lower in patients with HbA1c≥12% than in those with HbA1c<12% (p=0.046). Multiple linear regression analysis revealed a positive correlation between fasting C-peptide levels and serum IGF-I levels (p=0.040), whereas no correlations was found for BMI, duration of T2DM, FPG levels, or HbA1c. Moreover, patients with improved HbA1c levels during the follow up period showed a significant increase in serum IGF-I levels.
  
  
  
  Serum IGF-I levels were significantly decreased in Japanese patients with uncontrolled T2DM, and impaired insulin secretion may be a mechanism underlying this effect. When diagnosing acromegaly in patients with uncontrolled diabetes, these factors should be taken into account.
authors.affiliation: Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Suda
authors.affiliation: Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Japan.
authors.forename: Ryusaku
authors.initials: R
authors.lastname: Matsumoto
authors.affiliation: Division of Diabetes and Endocrinology, Kobe University Hospital, Japan.
authors.forename: Hidenori
authors.initials: H
authors.lastname: Fukuoka
authors.affiliation: Division of Diabetes and Endocrinology, Kobe University Hospital, Japan.
authors.forename: Genzo
authors.initials: G
authors.lastname: Iguchi
authors.affiliation: Division of Diabetes and Endocrinology, Kobe University Hospital, Japan.
authors.forename: Yushi
authors.initials: Y
authors.lastname: Hirota
authors.affiliation: Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Japan.
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Nishizawa
authors.affiliation: Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Japan.
authors.forename: Hironori
authors.initials: H
authors.lastname: Bando
authors.affiliation: Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Japan.
authors.forename: Kenichi
authors.initials: K
authors.lastname: Yoshida
authors.affiliation: Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Japan.
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Odake
authors.affiliation: Department of Nutrition, Kobe University Hospital, Japan.
authors.forename: Michiko
authors.initials: M
authors.lastname: Takahashi
authors.affiliation: Division of Diabetes and Endocrinology, Kobe University Hospital, Japan.
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Sakaguchi
authors.affiliation: Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Japan.
authors.forename: Wataru
authors.initials: W
authors.lastname: Ogawa
authors.affiliation: Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Japan. Electronic address: takahash@med.kobe-u.ac.jp.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Takahashi
mesh_terms: D000368:Aged; D001786:Blood Glucose / Q000378:metabolism*; D002096:C-Peptide / Q000378:metabolism; D003924:Diabetes Mellitus, Type 2 / Q000378:metabolism*; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism*; D006760:Hospitalization; D019382:Human Growth Hormone / Q000378:metabolism*; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D007564:Japan; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies
chemical_list: D001786:Blood Glucose; D002096:C-Peptide; D006442:Glycated Hemoglobin; D019382:Human Growth Hormone; D007334:Insulin-Like Growth Factor I; C583557:IGF1 protein, human; C517652:hemoglobin A1c protein, human
keywords: Asian population; Insulin like growth factor type 1; Type 2 diabetes