Factors affecting the prolongation of glycemic time in range among children with type 1 diabetes using continuous glucose monitoring systems: A case control study

Time in range is a reliable measure of the risk of diabetes complications. High percentage of patients with diabetes fail to achieve the recommended time in range (TIR) target of 70–180 mg/dl (3.9–10 mmol/l) >70%.

This study aimed to identify factors influencing TIR prolongation.

Children aged 1–17 years with >1-year type 1 diabetes (T1D) duration, treated with continuous subcutaneous insulin infusion (CSII) ≥3 months, using continuous glucose monitoring (CGM) or intermittently scanned CGM (is-CGM) ≥1 month, and with a registration time >70% were included. Data were collected during routine diabetology visits at an outpatient clinic. Insulin pump and CGM or is-CGM reports in the most recent 14 days were recorded using a dedicated software. Legal caregivers were also asked to complete a questionnaire on how the patients use the insulin pump functions and eating habits.

A sample of 110 patients was categorized into two groups: those with TIR >70% and TIR ≤70%. TIR ≤70% group presented with repeated hyperglycemia and a high glycemic variability coefficient of variation. We noted an acceptable hypoglycemia rate (3%), regardless of the TIR value. Patients with TIR >70% predominantly used predictive low glucose suspend system, maintained adequate intervals between insulin delivery and meal consumption, used the “bolus calculator” function, and more frequently created electronic reports.

Hyperglycemia and high glycemic variability prevent patients from achieving the target TIR. Advanced features in the CGM systems, premeal insulin bolus, and patients’ involvement in diabetes treatment are the main factors contributing to TIR prolongation.