Prevalence and Extent of Glycemic Excursions in Well-Controlled Patients with Type 2 Diabetes Mellitus using Continuous Glucose-Monitoring System

Background : Continuous glucose-monitoring system (CGMS) is a tool for assessment of glycemic excursions. Glucose variability is a risk factor independent of glycosylated hemoglobin (HbA1c) for diabetic complications; hence CGMS may be a better method for management of diabetes.
Aim: To evaluate the extent of glycemic excursions in well-controlled type 2 diabetic patients.
Setting and Design :The study was carried out in 21 diabetic patients on oral agents.
Materials and Methods: Patients underwent continuous glucose-monitoring by CGMS for 3 days. Number and duration of glycemic excursions, correlation coefficient (%) between CGMS and self-monitoring blood glucose (SMBG), mean absolute difference (%MAD) and complications of CGMS were analyzed.
Statistical Analyses : The statistical analyses were performed with the use of mean ± SD, t-test and Mann-Whitney test.
Results :The mean age of patients was 51.9 ± 9.7 years. The mean HbA1c was 6.7 ± 0.38%. The mean number of glycemic readings was 753.6 ± 203.5 times. The correlation coefficient was 0.83 and the MAD was 11.7 ± 8.0%, which were considerable. Three (14.2%) patients experienced, altogether, 9 hypoglycemic events with an average duration of 162 minutes. Twenty (94.7%) patients had hyperglycemic events. The mean duration of hyperglycemia was 19.4 ± 12.8 hours. All events were asymptomatic. Disconnection of device was the most common complication (3 patients).
Conclusion : This study demonstrated that well-controlled type 2 diabetic patients have a considerable number of hypoglycemia and hyperglycemia events that may be missed by SMBG.

Keywords
Continuous glucose-monitoring system, hyperglycemia, hypoglycemia, self-monitoring blood glucose, type 2 diabetes