Accuracy of a Fourth-Generation Continuous Glucose Monitoring System in Children and Adolescents with Type 1 Diabetes

Background: This study evaluated the safety and performance of the Guardian continuous glucose monitoring (CGM) system in children and adolescents with type 1 diabetes (T1D). Materials and Methods: Subjects 2-18 years of age (meanstandard deviation [SD] 13.13.9 years) with T1D and duration of diagnosis 1 year were enrolled at 11 sites in the United States and wore two Guardian Sensor 3 sensors in the abdomen and/or buttock. Sensors were connected to a transmitter paired with either a Guardian Connect system (i.e., mobile device with software application allowing display of sensor glucose [SG] values) or a Guardian Link 3 transmitter used as a Glucose Sensor Recorder (GSR). There were 145 participants who underwent a 6-h in-clinic frequent sample testing (FST) on day 1 (n=54), day 3 (n=48), or day 7 (n=43) postsensor insertion. During FST, SG values were compared with a Yellow Springs Instrument (YSI) plasma reference every 5-15min (n=124, 7-18 years of age; n=2, 2-6 years of age), or to a self-monitoring of blood glucose (SMBG) reference every 5-30min (n=19, 2-6 years of age). Results: The overall mean absolute relative difference (ARD +/- SD) between SG and reference values (YSI or SMBG) when calibrating approximately every 12h, was 10.9%+/- 10.7% (3102 paired points) for sensors communicating with the Guardian Connect system and 11.1%+/- 10.6% (2624 paired points) for sensors connected to the GSR. The overall percentage of SG values within +/- 20% of reference values >80mg/dL or within 20mg/dL of reference values 80mg/dL was 87.8% for the Guardian Connect system and 86.7% for the GSR, respectively. There was one device-related adverse event of contact dermatitis, but no serious device-related adverse events. Conclusions: The Guardian CGM system demonstrated good accuracy in children and adolescents. These findings support its use in sensor-integrated insulin pump platforms, as well as a standalone technology, for managing diabetes in pediatric populations.