Reduced Glucose Variability Is Associated With Improved Quality of Glycemic Control in Patients With Type 2 Diabetes: A 12-Month Observational Study

Abstract

Background: Current diabetes management relies mainly on hemoglobin A1C measurement to assess quality of treatment and to adjust therapy. We assessed the long-term effectivity of therapeutic adjustments in type 2 diabetes with specific focus on indices of glucose variability and multiple criteria for quality of glycemic control.

Methods: Continuous glucose monitoring data collected during an observational study involving 405 outpatients with type 2 diabetes were analyzed at baseline and after 12 months. We evaluated the following criteria for glucose variability and quality of glycemic control: mean amplitude of glycemic excursions (MAGE), SD around the mean sensor glucose, mean of daily differences (MODD), fasting and mean sensor glucose, time outside specified glucose ranges, the Glycemic Risk Assessment Diabetes Equation (GRADE) score, High Blood Glucose Index (HBGI), and Low Blood Glucose Index (LBGI). Patients were classified according to quartiles of MAGE.

Results: Indices of glucose variability were reduced by 15 to 23% (P < 0.001 for all) during 12 months in the upper MAGE quartile (>= 5.7 mmol/l). These reductions were associated with improvements in measures of glycemic control (P < 0.05), except for fasting sensor glucose (P = 0.23). Both time spent at < 3.9 mmol/l and at > 8.9 mmol/l decreased by 57% and 36% (P < 0.001 for both), respectively. MAGE and MODD correlated strongly with indices of glycemic control but weakly with A1C. The stepwise multiple regression analysis demonstrated that the mean amplitude of glycemic excursions and mean sensor glucose were the main determinants of time spent at < 3.9 mmol/l and at > 8.9 mmol/l (R² = 0.374 and 0.877, P < 0.001 for both).

Conclusions: Reduction of elevated glucose variability in type 2 diabetic outpatients is associated with lower risk of hypo- and hyperglycemia, and lower A1C values.




J Endocrinol Metab. 2011;1(2):64-72
doi: https://doi.org/10.4021/jem21w