Abstract 129: Continuous glucose monitoring in type 2 diabetes mellitus to assess glycemic control and glycemic variability

Background: Continuous glucose monitoring (CGM) can provide information beyond HbA1c and SMBG for glycemic control. Objectives: To assess glycemic variability (GV) and correlation of CGM metrics with HbA1c in type 2 diabetic (T2DM) individuals. Results: We enrolled 54 T2DM patients (age 53±7.8 years) on prior 3-month stable anti-diabetic medications for atleast 48-hours CGM (IPRO®2 Professional) with satisfactory agreement with glucometer cross-calibration. With 892.4±192.1 CGM readings, there was good correlation between CGM parameters and HbA1c (mean±SD- 9.45±2.57%) using Spearman's rho (π) analysis. There was positive correlation with HbA1c of glucose management indicator (GMI) (π=0.777, p<0.001), time-above-range (TAR) (π=0.739, p<0.001), area under curve (AUC) above limit (π=0.707, p<0.001), and negative correlation of Time-in-range (TIR) (π=-0.716, p<0.001). Looking into GV, there was no significant correlation of coefficient-of-variation (CV%) (π=-0.265, p=0.055) and weak positive correlation of standard deviation (SD) (π=0.274, p= 0.043) with HbA1c. More importantly, Time-below-range (TBR) ≥ 4% was seen in 8 (14.8%) patients, thus detecting unidentified asymptomatic hypoglycemias in 6 (11.1%) patients. Conclusions: Most CGM metrics correlated well with HbA1c, with additional advantage of identifying glycemic variability and asymptomatic hypoglycemias, These can be missed by infrequent home SMBG and HbA1c, and using CGM metrics can help tailor therapy to achieve a more optimal glycemic control, even in patients with relatively well-controlled HbA1c.