Distinct HbA1c trajectories have previously been identified in youth with established T1D. We used data from 3 international registries to evaluate whether distinct HbA1c trajectories occur from T1D onset. Participants were <18 yrs old at diagnosis and had at least 1 HbA1c measured within 12 months post-diagnosis, along with ≥3 duration-year aggregated HbA1c values over 10 yrs of follow-up. 7,292 participants from the Australasian Diabetes Data Network, 39,226 from the German/Austrian Diabetes Prospective Follow-up, and 3,704 from the U.S. T1D Exchange were included. Group-based modelling identified unique HbA1c trajectories from onset of T1D. Five distinct trajectories occurred in all 3 registries (Figure), with similar patterns of proportion by group. Over 50% had stable HbA1c in or near target. Conversely, ∼15% in each registry were characterized by stable HbA1c >8.0%, and ∼11% had values that began in or near target but then increased. Only ∼5% of youth were suboptimal from diagnosis with an increasing HbA1c. This group differed from others with higher rates of minority status and older age at diagnosis across all 3 registries (p≤0.001). We observed similar post-diagnostic HbA1c patterns across 3 international registries. Identifying youth at greatest risk for deterioration in HbA1c over time may allow clinicians to intervene early to avert increasing HbA1c.


J. Sherr: Advisory Panel; Self; Bigfoot Biomedical, Cecelia Health. Consultant; Self; Eli Lilly and Company, Lexicon Pharmaceuticals, Inc., Medtronic, Sanofi, T1D Exchange. A. Schwandt: None. H. Phelan: None. M.A. Clements: Consultant; Self; Glooko, Inc. Other Relationship; Self; Glooko, Inc. R.W. Holl: None. P.Z. Benitez-Aguirre: None. K. Miller: None. J. Woelfle: Advisory Panel; Self; Novo Nordisk A/S. T. Dover: None. D.M. Maahs: Advisory Panel; Self; Eli Lilly and Company, Insulet Corporation, Medtronic, Novo Nordisk A/S. Consultant; Self; Abbott, Sanofi. Research Support; Self; Bigfoot Biomedical, Dexcom, Inc., Roche Diabetes Care, Tandem Diabetes Care. E. Fröhlich-Reiterer: None. M.E. Craig: None.


German Centre for Diabetes Research (FKZ82DZD01402); German Diabetes Association; European Foundation for the Study of Diabetes; INNODIA; The Leona M. and Harry B. Helmsley Charitable Trust

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