title: The utility of glycated hemoglobin in identification of impaired glucose tolerance.
abstract: The purpose of this study was to investigate the ability of measurements of glycated hemoglobin HbAlc by a highly precise method to characterize impaired glucose tolerance (IGT). HbAlc was measured by an isoelectric focusing method (CV = 2.1% using mean of duplicates) in 100 consecutive persons referred to the laboratory by their general practitioners for an oral glucose tolerance test (OGTT) because of random blood glucose measurements within the uncertain range or positive urine tests for glucose. The patients were classified according to the most recent World Health Organization criteria in normals (n = 64), persons with IGT (n = 27) and diabetics (n = 9). HbAlc in persons with IGT was significantly higher (p less than 0.001) than in normals. It was possible to calculate a reference interval of IGT from 5.6-7.5% (mean +/- 2SD), but a considerable overlap with the reference interval of non-diabetics (5.2-6.8%) make measurements of HbAlc insufficient for diagnosis of IGT. Poor correlation was seen between plasma glucose measurements and HbAlc in persons with normal OGTT and IGT (r = 0.3). The question is, whether measurements of HbAlc provides additional information in IGT, identifying those with highest mean blood glucose concentrations in daily life, thereby being of value in itself in evaluation of glucose tolerance.
authors.affiliation: Department of Clinical Chemistry, Odense University Hospital, Denmark.
authors.forename: M L
authors.initials: ML
authors.lastname: Larsen
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood*; D001786:Blood Glucose / Q000378:metabolism*; D003920:Diabetes Mellitus / Q000097:blood*; D005951:Glucose Tolerance Test; D006442:Glycated Hemoglobin / Q000032:analysis*; D006801:Humans; D012016:Reference Values
chemical_list: D015415:Biomarkers; D001786:Blood Glucose; D006442:Glycated Hemoglobin