Background: Early initiation of CGM after T1D diagnosis has been associated with lower HbA1c in the years following diagnosis in single-institution studies. This multi-institution study evaluated the association between the timing of CGM initiation and HbA1c at 3 years post-diagnosis.

Methods: Data were obtained from the T1D Exchange QI Collaborative, representing 52 centers across the US. Of the 33,942 youth ≤18 years with T1D >12 months in the Collaborative data set, those who started CGM within 12 months of diagnosis were included. LOESS plots evaluated the relationship between timing of CGM initiation and HbA1c.

Results: Of the 5,339 youth included in this analysis, median age was 9 (IQR 6) and 26% had public health insurance. Initiation of CGM occurred within 3-months of diagnosis for 43%, between 3-6 months for 27%, and 6-12 months for 30%. There was no significant difference in CGM initiation based on insurance or the social construct of self-identified race and ethnicity, used as an indicator of systemic racism. Median HbA1c at 3 years was lower for those who initiated CGM within 3 months and between 3-6 months of diagnosis compared to those starting CGM at 6-12 months (7.3 ± 1.7 and 7.5 ± 1.7 vs. 7.9 ± 1.7; Figure 1).

Conclusion: In summary, early initiation of CGM within the first 6 months of diagnosis is related to improved A1c outcomes at 3 years post-diagnosis.


E.A.Mann: None. P.Gomez: None. O.Ebekozien: Advisory Panel; Medtronic, Research Support; Eli Lilly and Company, Dexcom, Inc. P.Prahalad: None. S.Rompicherla: None. N.Noor: None. B.Miyazaki: None. L.Golden: None. J.Sarhis: None. H.K.Akturk: Advisory Panel; Senseonics, MannKind Corporation, Research Support; Medtronic, Tandem Diabetes Care, Inc., Dexcom, Inc., REMD Biotherapeutics, Eli Lilly and Company, IM Therapeutics. J.M.Lee: Advisory Panel; GoodRx, Consultant; Tandem Diabetes Care, Inc. D.Desalvo: Consultant; Dexcom, Inc., Research Support; Insulet Corporation.

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