Impact of Oral Glucose Tolerance Test on Extent of Hemoglobin Glycation

• Conditions: Oral Hypoglycaemic Overdose; Blood Glucose, High

• Registration Number: NCT04018430
• Lead Sponsor: Urs E. Nydegger

Brief Summary

The glycation extent of human hemoglobin is under control of the Maillard reaction, a chemical interaction between an amino acide and a reducing sugar. About 5% ( 31.1 mmol/mol) of hemoglobin molecules secluded in a red blood cell are glycated; excessive values \> 6.5% point to prediabetes or overt diabetes mellitus. To ascertain the diagnosis doctors prescribe oral glucose tolerance upon which glucose concentrations in blood increase - how much HbA1c reacts under these circumstances is ill known.

Detailed Description

Medical laboratory assays for delineation of impaired glucose metabolism and overt diabetes mellitus, beyond measurement of (fasting) blood serum or plasma glucose levels, include extent of hemoglobin A1c glycation, concentration of fructosamines, insulin concentrations to calculate the homeostasis model assessment (HOMA) index and other clinically putative biomarkers of glucose homoeostasis. HbA1c levels form now part of routine elucidation of metabolic disorders and are used for therapy monitoring. Initially used to monitor glucose levels in follow-up care of diabetics it is considered as a track marker of ups and downs of blood glucose concentrations. Its behavior under the 2 h period of oral glucose tolerance tests (OGTT) is ill known - most clinicians believe the glycation extent will not change. Since the dynamics of glycation is temperature dependent,non-febrile patients under OGTT likely keep their glycation extent between time zero and 120 min after glucose charge constant but this has not been investigated and with the sensitive lab assays for HbA1c now in use we postulate a significant increase in glycation. The Patient Registry includes recruited children and adults sick from diabetes, overweight or metabolic syndrome as a whole. Three medical offices will address their patients to the VidyMed lab to perform the OGTT framed by lab assays on venous blood samples

Study Timeline

• Status Verified: 2019-07
• Study First Submitted: 2019-07-10
• Study First Submitted QC: 2019-07-10
• Last Update Submitted: 2019-07-10
• Study First Posted: 2019-07-12
• Last Update Posted: 2019-07-12
• Study Start: 2019-09-01
• Primary Completion: 2020-09-30
• Study Completion: 2021-09-30

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: 100

Inclusion Criteria

• apparently healthy subjects or subjects supposedly experiencing a metabolic disease (e.g. prediabetes) Subjects with asked for fasting blood glucose

Exclusion Criteria

• current steroid use thyroid dysfunction (free-thyroxin levels < 9 or > 19 pmol/L, hsCRP > 10 mg/L hospitalized

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
HbA1c concentration upon oral glucose tolerance testing	48 hours	HbA1c significantly increases upon oral glucose tolerance testing

Trial Locations

Locations (1)

University of Bern; 🇨🇭 Bern, Kanton Bern, Switzerland