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Study of In Vivo Glucose Metabolism in High-fat Diet-fed Mice Using Oral Glucose Tolerance Test (OGTT) and Insulin Tolerance Test (ITT)
08:13

Study of In Vivo Glucose Metabolism in High-fat Diet-fed Mice Using Oral Glucose Tolerance Test (OGTT) and Insulin Tolerance Test (ITT)

Published on: January 7, 2018

Relationship between glycated haemoglobin levels and mean glucose levels over time

D M Nathan1, H Turgeon, S Regan

  • 1Diabetes Center, Department of Biostatistics, Massachusetts General Hospital, 50 Staniford Street, Suite 340, Boston, MA 02114, USA. dnathan@Partners.org

Diabetologia
|September 14, 2007
PubMed

Insights

Glycated hemoglobin (HbA1c) strongly correlates with mean glucose levels measured by continuous glucose monitoring over 8-12 weeks. This study demonstrates that HbA1c can be reliably converted to average glucose levels for better diabetes management.

Area of Science:

  • Endocrinology
  • Metabolic Diseases
  • Clinical Chemistry

Background:

  • HbA1c is the standard measure for chronic glycemia, guiding diabetes treatment.
  • Daily diabetes management relies on capillary glucose readings (mmol/l).
  • A direct correlation between HbA1c and mean glucose levels is needed for treatment adjustments.

Purpose of the Study:

  • To determine the relationship between continuous glucose monitoring (CGM) and HbA1c levels.
  • To assess if HbA1c can be expressed in mmol/l, aligning with self-monitoring results.

Main Methods:

  • A longitudinal observational study involving 25 participants (22 with diabetes).
  • Continuous glucose monitoring (CGM) measured interstitial glucose every 5 minutes for 12 weeks.
  • HbA1c and capillary glucose levels were measured periodically to validate CGM accuracy.

Main Results:

  • HbA1c levels at 8 and 12 weeks showed a strong correlation (r=0.90) with preceding CGM data.
  • Both curvilinear and linear regression models accurately represented the relationship.
  • HbA1c values were successfully transformed into calculated mean glucose levels.

Conclusions:

  • HbA1c is a reliable indicator of average glycemia over the preceding 8-12 weeks.
  • Translating HbA1c into average glucose levels is feasible for clinical reporting and management.
Abstract

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