Background and Aims: Advanced Hybrid closed loop (AHCL) algorithm combines automated basal rate with additional enhancement when a rise in glucose level is detected. This study assessed the effectiveness and safety of AHCL with unannounced meals.

Methods: Fourteen participants were using Medtronic AHCL system at home for a mean of 72.6 days. Each participant spent 4 days in a protected free-living environment while consuming pre-defined meals consisting of up to 80 grams of carbohydrates each day. On day 5, participants initiated a 3-months unannounced meal phase at their homes with the instruction to announce only meals containing over 80 grams.

Results: Fourteen subjects with T1DM (10 males, mean age 44.3±3.9 years) and baseline HgbA1C% of 6.75± 1.2 were enrolled. Patients spent 97±3% of time in Auto-Mode, with mean SG of 157.8±19.2. Mean %time in range70-180was 67.6±12.8, %time <70 mg/dL of 2±1.7%, and % time <54 mg/dL of 0.4±0.5%. Table 1 summarizes the glycemic indices.

Conclusion: Medtronic AHCL system is designed for best performance with meal announcement. Nevertheless, when meals containing ≤ 80 gram of carbohydrates are consumed without meal announcement, the system can provide safe glycemic control with about 67.6% of TIR.


A. Tirosh: Advisory Panel; Self; Novo Nordisk Inc., Sanofi. R. Shalit: Research Support; Self; Medtronic. M. Laron Hirsh: None. O. Cohen: Employee; Self; Medtronic. N. Kurtz: Employee; Self; Medtronic. A. Roy: Employee; Self; Medtronic. B. Grosman: Employee; Self; Medtronic.



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