In the Pilot 4T study (diagnosed July 2018 to May 2020, A1c target <7.5%, n=135) , early CGM initiation and remote patient monitoring (RPM) was associated with lower A1c. We hypothesized that tightening A1c targets to <7% would further lower A1c.

All youth with newly diagnosed T1D from June 2020 to December 2021 were offered CGM initiation in the first month of diagnosis and RPM (4T cohort, n=115) . We compared A1c outcomes in the 4T cohort with the Pilot 4T cohort and the Historical cohort who were not offered early CGM (diagnosed 2014-2016, n=272) . We visualized population-based A1c trajectories using locally estimated scatter plot smoothing (LOESS, Fig) .

Mean A1c at diagnosis was similar in the 4T and Pilot 4T cohorts (12.3% v 12.2%) and higher than the Historical cohort (10.7%) . The median age of diagnosis was 11.2 years [7.1, 14], 53% male, 35% non-Hispanic White, and 65% with private insurance in the 4T cohort. CGM initiation occurred within 30 days of diagnosis in 98.3% of youth. At 3, 6, and 9 months post-diagnosis, those in the 4T cohort had LOESS-based mean A1c differences of 0.33%, 0.36%, and 0.42% lower than the Pilot 4T cohort and 0.39%, 0.62%, and 0.96% lower than the Historical cohort.

Early CGM initiation and RPM combined with tighter glucose targets was associated with a lower A1c compared to historical cohorts. These data support implementation of the 4T program with tight target setting in youth with T1D.


P.Prahalad: None. D.M.Maahs: Advisory Panel; Abbott Diabetes, Eli Lilly and Company, Medtronic, Novo Nordisk, Sanofi, Consultant; Aditx Therapeutics, Inc., Biospex. 4t study group: n/a. V.Ding: None. D.P.Zaharieva: Research Support; Insulet Corporation, International Society for Pediatric and Adolescent Diabetes, Leona M. and Harry B. Helmsley Charitable Trust. A.Addala: None. F.K.Bishop: None. D.Scheinker: None. R.Johari: None. M.Desai: None. K.K.Hood: Consultant; Cecelia Health, Havas Health, Insulet Corporation, LifeScan Diabetes Institute.


Stanford Diabetes Research Center (P30DK116074) and R18DK122422; Dexcom; Lucile Packard Children’s Hospital Auxiliaries Endowment

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