Background: The RCT data on CGMS and GV in patients with T2DM have used limited measure of GV metrics. In patients with T2DM on CGMS, we examined whether the use of blinded or unblinded CGMS will affect their GV across a broad swatch of metrics.

Methods: A randomized control study involving 40 subjects with T2DM was done [50% females, mean (SD) age 59 years (12.5) , BMI (8.1) , mean (SD) screening HbA1c 7.59% (1.2) ]. Patients were randomized (1:1) to either 1 unblinded (Freestyle Libre) +1 blinded (Freestyle Libre Pro) CGMs or 2 blinded CGMS (Freestyle Libre Pro) for 16 weeks. Sensors were replaced every 2 weeks with an in-person visit. Multiple GV metrics were calculated from the blinded CGM at baseline (Week 0-Week2) and end-intervention (Week 14-16) . Participants randomized to the Unblinded/Blinded CGM group were instructed to use the CGM as they wished. Participants randomized to the Blinded CGM group were instructed to continue checking their fingerstick glucose as usual.

Measured GV metrics included the following: mean glucose, standard deviation (SD) , and coefficient of variation (CV) , continuous overlapping net glycemic action (CONGA) , liability Index, J-index, low and high blood glucose index (LBGI/HBGI) , glycemic risk assessment diabetes equation (GRADE) , mean of daily differences (MODD) , average daily risk range (ADRR) , mean amplitude of glycemic excursions (MAGE) , mean of daily differences (MODD) , Area Under Curve (AUC) , time spent in range (TIR) , Glucose Management Indicator (GMI) , number of episodes below 55 and glycemic variability percentage (GVP) .

Results: In this study, we found that was no significant difference in all GV metrics between the blinded/ blinded CGMS group and unblinded/blinded CGMS group at baseline and end intervention.

Conclusion: The novelty of this study is the extensive analysis of GV across multiple metrics in patients with T2DM on CGMS and CGMS usage did not significantly alter GV.


Y.Lee: None. A.Mehfooz: None. Q.Wang: None. L.S.Chow: Other Relationship; Dexcom, Inc.

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