Background: In 2022, the smartphone application and pump software for the t:slim X2 with Control-IQ technology updated to allow bolus insulin programming from a user’s personal smartphone (mobile bolus, MB) in the United States. The aim of this study was to determine if MB increased bolus frequency in users who bolus <3 times/day.

Methods: De-identified data from users with low bolus frequency and >21 days with 70% CGM pre-and post MB were analyzed for changes in bolusing behavior and Time in Range (TIR) before and after MB.

Results: A total of 4,470 users bolused <3 times/day and upgraded to MB. After MB start, these users increased the number of boluses per day from 2.2 to 2.7 (+0.5 per day, p<0.001, table). After MB upgrade, approximately 1 bolus/day (36% of boluses) were delivered on the smartphone app instead of the insulin pump. TIR improved discreetly, with children <12 years old experiencing 34 more minutes in target range each day (p<0.01). Of all, 87% of users were very satisfied or satisfied with the MB feature.

Conclusions: For users with low bolus frequency, the MB feature meaningfully increased the number of boluses given each day, and can be leveraged as a way to increase daily bolusing behaviors.


L.H.Messer: Advisory Panel; Lilly, Consultant; Dexcom, Inc., Capillary Biomedical, Inc., Employee; Tandem Diabetes Care, Inc., Research Support; Beta Bionics, Inc., Medtronic, Insulet Corporation. L.Mueller: Employee; Tandem Diabetes Care, Inc., Stock/Shareholder; Tandem Diabetes Care, Inc. E.W.D'souza: None. S.Habif: Employee; Tandem Diabetes Care, Inc. J.E.Pinsker: Employee; Tandem Diabetes Care, Inc.


Tandem Diabetes Care, Inc.

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