2885-LB: The Impact of On-Time and Late Bolusing on Postprandial Glycaemic Control in MiniMed 780G System Users: A Real-World Analysis of over 389,796 Meals

Introduction and Objective: We explored the relationship between bolus timing and postprandial (pp) glycaemic control in real-world MiniMed™ 780G system users with T1D. Methods: Utilizing a machine learning tool that detects meals based on sensor glucose, we analysed 389,796 meals from 18,513 users (EMEA region, JAN2023-FEB2026). First, 4-hour postprandial glycaemic control was assessed for meals by time of day based on user age (<16y/16-28y/29-42y/43-55y/>55y), bolusing type (BT: on-time bolus within 15 minutes, OTB/ late bolus of 15-90 minute delay, LB) and carbohydrate input (CI: ≤26g/26-45g/>45g). Second, to estimate the impact of bolus timing on TIR(pp), a linear mixed-effects model was applied for meals per age group and BT, adjusting for CI and including user as random effect. Results: OTB meals showed a 5-6% higher TIR(pp) than LB meals. In age groups, highest TIR(pp) was observed for OTB meals in users >55yr (62.15%). In CI groups, OTB meals of ≤26g carbohydrates showed highest TIR(pp) (60.05%, Table). In the second analysis, a 30-minute bolus delay for LB meals reduced TIR(pp) by ~4% in all age groups. Bolusing 30 minutes earlier for OTB meals had minimal impact. For both LB and OTB meals, higher CI was associated with lower TIR(pp). Conclusion: OTB meals and meals with low CI provide best pp glycaemic control. In LB, bolus delay substantially reduces TIR(pp), whereas in OTB, earlier bolusing yields minimal benefit. Disclosure M. Juachon: None. M. Liu: Employee; Current; Medtronic. J.J. Shin: Employee; Current; Medtronic. T. van den Heuvel: Employee; Current; Medtronic. O. Cohen: Employee; Current; Medtronic.