Contributions of intermittently scanned continuous glucose monitoring frequency and bolus insulin dosing on time in range: Analysis of data from CGM and connected insulin pens.

Background and aims: Integration of data from continuous glucose monitoring (CGM) and connected insulin pens allows us to investigate their use to optimise glucose control. This study examines how insulin bolus frequency reported by connected pens and frequency of glucose scans by an intermittently-scanned continuous glucose monitoring (isCGM) system relate to glycaemic control in a population of real-world European users.

Methods: Data from glucose sensors and connected insulin pens were aggregated for LibreView users who integrated their connected pen by January 1, 2024. The most recent 90-day window with ≥30 days' glucose data and ≥15 days of insulin bolus doses following their integration date was analysed. We stratified users by categories of average isCGM scan frequency: low (<6.1 scans/day), medium (6.1-14.0 scans/day) or high (>14.0 scans/day), and average bolus frequency: low (<3.1 boluses/day), medium (3.1-6.7 boluses/day) or high (>6.7 boluses/day).

Results: Data from 10,993 users was available over 80.6 days/user. Median scans/day were 9.3 [6.1-14.0] and median bolus/day was 4.5 [3.1-6.7]. Increased daily scans were associated with greater time in range (TIR) 70-180 mg/dL (3.9-10.0 mmol/L) within each of the low, medium, and high bolus frequency groups. Increased bolus frequency was associated with increased TIR in the lowest scanning frequency group. Similar outcomes were observed for time above range (TAR) and glycaemic variability.

Conclusions: While glucose monitoring frequency and insulin bolus dosing are both indicators of engagement with diabetes self-management, higher TIR has a closer association with increased rates of user engagement with isCGM than with increased rates of bolus dosing.