Aiming for the Best Glycemic Control Beyond Time in Range: Time in Tight Range as a New Continuous Glucose Monitoring Metric in Children and Adolescents with Type 1 Diabetes Using Different Treatment Modalities

Introduction. To evaluate time in tight range (TITR) 70-140 mg/dL (3.9- 7.8 mmol/L), its correlation with standard continuous glucose monitoring (CGM) metrics and the clinical variables that possibly have a substantial impact on its value, in a large cohort of pediatric subjects using different treatment strategies. Material and methods. A total of 854 children and adolescents with type 1 diabetes were consecutively recruited in this real-world, dual-center, cross-sectional study. Participants were categorized into four treatment groups (multiple daily injections + real-time CGM, multiple daily injections + intermittently scanned CGM, sensor augmented pump, and hybrid closed loop (HCL)). Demographical and clinical data, including CGM data, were collected and analyzed. Results. The overall study population exhibited an average TITR of 36.4±12.8%. HCL users showed higher TITR levels compared to the other treatment groups (p<0.001). A time in range (TIR) cut-off value of 71.9% identified subjects achieving a TITR≥50% (AUC 0.98; 95%CI 0.97–0.99, p<0.001), and a strong positive correlation between these two metrics was observed (r=0.95, p<0.001). An increase in TIR of 1% was associated with 1.84 (R2 Nagelkerke=0.35, p<0.001) increased likelihood of achieving TITR≥50%. Use of HCL systems (B=7.78; p<0.001), disease duration (B=-0.26, p=0.006), coefficient of variation (B=-0.30, p=0.004), and glycated haemoglobin (B=-8.82; p<0.001) emerged as significant predictors of TITR levels. Conclusions. Our study highlights that most children and adolescents with type 1 diabetes present TITR levels below 50%, except those using HCL. Tailored interventions and strategies should be implemented to increase TITR.