This study assessed HbA1c across the lifespan in people with T1D in Austria/Germany, Sweden, and the United States (U.S.) between 2011 and 2017. Data extracted from the DPV, Austria/Germany (n = 25651 in 2011, n = 29442 in 2017); SWEDIABKIDS/NDR, Sweden (n = 44474 in 2011, n = 53690 in 2017); and T1D Exchange, U.S. (n = 16198 in 2011, n= 17087 in 2017) registries were included in the analysis. Mean HbA1c across the lifespan in 2017 and changes in mean HbA1c between 2011 and 2017 overall and by age cohorts were analyzed. In 2017 mean HbA1c for adults ≥45 years converged across registries; HbA1c levels for subjects <25 years were highest in the U.S. (Figure). Controlling for age, sex, and T1D duration, overall HbA1c increased in the U.S. between 2011 and 2017 (2011=8.02%, 2017=8.26%, p<.01); decreased in Sweden (8.06%, 7.74%, p<.01); and did not change in Austria/Germany (7.84%, 7.84%, p=.49). Controlling for sex and T1D duration, mean HbA1c decreased between 2011 and 2017 in all age cohorts in Sweden (all p<.01). In the U.S., HbA1c increased in subjects <45 years and ≥65 years (all p<.05) and did not change in subjects 45-<65 years (p=.06). In Austria/Germany, HbA1c decreased in subjects 13-<19 years (p<.01), did not change in subjects <13 years (p=.26) and 19-<25 years (p=.88), and increased in subjects ≥25 years (all p<.05). Further research is warranted to better understand causes of geographic disparities in glycemic control.


A. Albanese-O’Neill: Consultant; Self; American Diabetes Association. J. Hermann: None. A. Svensson: None. K. Miller: None. K. Raile: None. K. Akesson: None. P. Calhoun: Stock/Shareholder; Self; Dexcom, Inc. K. Eeg-Olofsson: 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. R.W. Holl: None. R. Hanas: Advisory Panel; Self; Abbott, Novo Nordisk A/S. Speaker’s Bureau; Self; Sanofi. Other Relationship; Self; AstraZeneca.


German Center for Diabetes Research; The Leona M. and Harry B. Helmsley Charitable Trust (G-2016PG-T1D053)

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