Background: We compared glycemic outcomes and participant experience during MiniMed™ 780G Advanced Hybrid Closed Loop (AHCL) system use while announcing all meals vs. announcing meals at will.

Methods: Participants with T1DM used the AHCL system at home during two 90 days phases in which they were given instructions first to announce all meals (AM) , and next, for meals containing up to 80 grams of carbohydrates, to announce meals at will (AMW) .

Results: Fourteen subjects (males, mean age 44.3±11) with T1DM were enrolled, with a baseline A1C of 6.9±1%. Table 1 summarizes glycemic indices and AHCL data, demonstrating that patients chose to bolus only slightly less during AMW compared to AM (5.5 vs. 5.2 boluses) , without resultant deterioration in glycemic indices (A1c 6.4 vs. 6.5%, TIR 78.1 vs. 78.8%, p=ns) . Subjects surveyed regarding the option not to have to bolus for all meals experienced a significant reduction in reported effort to manage diabetes (p=0.045) and 86% endorsed worrying less about their diabetes. Most (93%) preferred the AMW phase of the study.

Conclusion: The MinMed™ AHCL system is designed for optimal performance with meal announcement. Nonetheless, when meals containing < 80 grams of carbohydrates are consumed with announcement of meals at will, there is a slight reduction in the number of daily boluses with no decline in glycemic control, yet markedly less diabetes related distress and improved treatment satisfaction.


N. Minsky: None. R. Shalit: Speaker's Bureau; AstraZeneca, Boehringer Ingelheim International GmbH, Eli Lilly and Company, Medtronic, Novo Nordisk. O. Cohen: Employee; Medtronic. N. Kurtz: Employee; Medtronic. A. Roy: Employee; Medtronic. B. Grosman: Employee; Medtronic. A. Tirosh: Advisory Panel; Abbott Diagnostics, AstraZeneca, Boehringer Ingelheim International GmbH, Merck & Co., Inc., Novo Nordisk, Sanofi. Consultant; Bayer AG, DreaMed Diabetes, Ltd. Research Support; Medtronic. Speaker's Bureau; Eli Lilly and Company.

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