Relationship between Time in Range, Glycemic Variability Metrics and Daily Scan Rate in Children with Type 1 Diabetes

Objective: The adoption of intermittently scanned continuous glucose monitoring (isCGM) systems can improve glycemic control and quality of life in type 1 diabetes (T1D) individuals, but few studies have involved children and adolescents. The aim of this research was to explore the relationship between time in range (TIR: 70-180 mg/dL), glycemic variability (GV) metrics and daily scan rate in a pediatric population with T1D during real-life conditions. Method: Monitoring data were collected in a pilot study between January 2018 and February 2020 within the Advanced Intelligent Distant-Glucose Monitoring (AID-GM) project, which involved 27 T1Dpediatric patients under multiple daily injection insulin-therapy. All participants used the isCGM Abbott’s FreeStyle Libre system. 14-days monitoring windows were split into 10 equally sized rank ordered groups considering different ranking variables in separate analyses: glucose standard deviation (SD), continuous overall net glycemic action at 1-hour (CONGA1), average daily risk range (ADRR), and daily scan rate. For each ranking, a Dunn's test was performed to verify if TIR was significantly different among groups (p-value<0.05); relationships were investigated through Spearman’s correlation coefficient. Result: Each patient was monitored on average for eight months. GV metrics showed a negative relationship with TIR (SD: r=-0.98; CONGA1 and ADRR: r=-0.99; p-value<0.01), which was significantly higher in groups with the lowest variability. Instead, daily scan rate revealed a positive relationship with TIR (r=0.75; p-value<0.02), which was significantly higher in the highest scan rate group (30.02 scans/day) compared to the lowest group (2.88 scans/day). Conclusion: GV reduction and elevated scan rate through isCGM systems are associated with high time spent in the euglycemic range in children and adolescent with T1D.