Visual Abstract

Continuous glucose monitor (CGM) use in diabetes is associated with improved clinical outcomes. However, evidence is lacking on whether changes in outcomes differ by CGM type. We compared A1c changes between FreeStyle Libre and Dexcom recipients. We conducted a retrospective study using IBM Explorys US EHR database on adults (18+ years) who were CGM naïve, with non-gestational T1D or T2D treated with rapid- or short-acting insulin, prescription for a FreeStyle Libre/FreeStyle Libre 14 day or Dexcom G5/G6 system in Q4 2017- Q2 2020, A1c data within 180 days prior to and within 60-300 days after CGM prescription, and baseline A1c ≥ 7%. After propensity score matching on demographics (age, gender, race, insurance), baseline A1c, and comorbidities, we compared A1c changes pre/post CGM between devices. Separate analyses were conducted for T1D and T2D and a sub-analysis among those with baseline A1c ≥ 8%. In both matched T1D (N=348) and T2D (N=330) cohorts, and in sub-analyses, recipients of both device types exhibited a significant A1c reduction after CGM prescription. T2D patients exhibited the greatest reductions, particularly those with initial poor glycemic control. The amount of reduction was not statistically significantly different between devices. CGM recipients experienced a significant improvement in A1c regardless of CGM manufacturer.


E. Miller: Advisory Panel; Self; Abbott Diabetes, Boehringer Ingelheim Pharmaceuticals, Inc., Eli Lilly and Company, Novo Nordisk Inc., Research Support; Self; Pendulum Therapeutics, Research Support; Spouse/Partner; Abbott Diabetes. J. Joseph: Employee; Self; Abbott. I. J. Reyes: None. Y. Nabutovsky: Employee; Self; Abbott, Stock/Shareholder; Self; Abbott. N. Virdi: Employee; Self; Abbott Diabetes, Stock/Shareholder; Self; Johnson & Johnson. I. B. Hirsch: Consultant; Self; Abbott Diabetes, Bigfoot Biomedical, Inc., Research Support; Self; Insulet Corporation, Leona M. and Harry B. Helmsley Charitable Trust, Medtronic.

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