Background: The Dexcom G6 continuous glucose monitoring (CGM) system differs from Dexcom’s earlier G5 system in that G6 includes a predictive “Urgent Low Soon” (ULS) alert that notifies users when an estimated glucose value (EGV) ≤55 mg/dL is predicted in the next 20 minutes. The effect of the ULS alert on the distribution of EGVs was evaluated in the context of traditional threshold alerts.

Methods: We identified individuals who had used G5 and transitioned to G6 between 5/1/2018 and 10/31/2018. Evaluable data were from a subset of 4083 users who had maintained low threshold alerts at either 70 or 80 mg/dL, who used a smartphone to view and upload ≥30 days of data from each system, and who maintained the G6 ULS alert in its default (enabled) state.

Results: Use of the 80 mg/dL low threshold alert was associated with higher mean EGVs, less hypoglycemia, and more hyperglycemia than use of the 70 mg/dL low threshold alert (Table). Over 97% of the G6 systems were used with the ULS feature enabled, and the ULS alert was activated less than once daily. At either low threshold setting, the transition to G6 was associated with reductions in hypoglycemia (<55 and <70 mg/dL) and severe hyperglycemia (>250 mg/dL).

Conclusions: When used in the context of traditional low threshold alerts, the predictive ULS alert may enable timely and appropriate interventions that contribute to further reductions in hypoglycemia among CGM-experienced users.


M. Derdzinski: Employee; Self; Dexcom, Inc. J. Welsh: Employee; Self; Dexcom, Inc. S. Puhr: None. T.C. Walker: Employee; Self; Dexcom, Inc. A. Parker: Employee; Self; Dexcom, Inc. A. Jimenez: Employee; Self; Dexcom, Inc.

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