title: A higher proinsulin response to glucose loading predicts deteriorating fasting plasma glucose and worsening to diabetes in subjects with impaired glucose tolerance.
abstract: To evaluate the clinical significance of proinsulin determination, we measured glucose, insulin, C-peptide and proinsulin during 75-g oral glucose loading in 59 patients. In a 2.5-year follow-up study of 37 subjects with impaired glucose tolerance (IGT) at the initial test, 11 patients changed from IGT to a normal state and 5 patients showed worsening to overt Type 2 diabetes with elevation of fasting plasma glucose; 21 patients remained unchanged. Although our data showed that both fasting (IGT: p = 0.4523) and 120-min plasma glucose (IGT: p = 0.8168) values at the initial test were not significantly correlated with increased fasting plasma glucose levels in a 2.5-year follow-up study, subjects with a higher 120-min proinsulin response to glucose during the initial OGTT showed a significant correlation (IGT: p < 0.0001) with increased fasting plasma glucose levels after follow-up period and developed Type 2 diabetes. The present findings suggest that the proinsulin response to glucose loading might be a useful indicator for predicting worsening to diabetes in subjects with impaired glucose tolerance.
authors.affiliation: The Fourth Department of Medicine, Saitama Medical School, Japan.
authors.forename: I
authors.initials: I
authors.lastname: Inoue
authors.forename: K
authors.initials: K
authors.lastname: Takahashi
authors.forename: S
authors.initials: S
authors.lastname: Katayama
authors.forename: Y
authors.initials: Y
authors.lastname: Harada
authors.forename: K
authors.initials: K
authors.lastname: Negishi
authors.forename: J
authors.initials: J
authors.lastname: Ishii
authors.forename: S
authors.initials: S
authors.lastname: Shibazaki
authors.forename: M
authors.initials: M
authors.lastname: Nagai
authors.forename: S
authors.initials: S
authors.lastname: Kawazu
mesh_terms: D000284:Administration, Oral; D001786:Blood Glucose / Q000378:metabolism*; D016022:Case-Control Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000175:diagnosis*; D005215:Fasting / Q000097:blood*; D005260:Female; D005500:Follow-Up Studies; D018149:Glucose Intolerance / Q000097:blood*; D005951:Glucose Tolerance Test; D006801:Humans; D007328:Insulin / Q000378:metabolism; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011384:Proinsulin / Q000378:metabolism*; D012044:Regression Analysis; D012636:Secretory Rate / Q000502:physiology
chemical_list: D001786:Blood Glucose; D007328:Insulin; D011384:Proinsulin