Background: There is a large variation in mean HbA1c levels even between high-income countries, with a decrease over time in HbA1c in some countries but an increase in others. Sweden has experienced a steady decrease in HbA1c over the past 10 years. The aim of this study was to illustrate how changes in HbA1c during the first two years after diagnosis in children and adolescents is related to calendar year for diagnosis of type 1 diabetes from 2010 to 2017.
Methods:The Swedish SWEDIABKIDS registry collects data every ~3 months and has > 95% coverage up to age 18 years. We plotted all available HbA1c data vs. diabetes duration, presented as separate Loess curves per 2 consecutive year groups.
Results: In total, 5,102 patients contributed with 51,550 HbA1c values over 8 years. HbA1c at onset has slightly increased from 93.9 to 95.0 mmol/mol (10.7 to 10.8 %) between 2010 and 2017. The HbA1c nadir (lowest level during first year) is around 4 months, and has become lower over the years. Early HbA1c tracking is apparent and is established with a difference between the groups from 1 year’s diabetes duration.
Conclusions: Intensification of early diabetes treatment, resulting in a lower HbA1c nadir at 4 months and lower HbA1c from 1 year onwards is related to HbA1c two years after diagnosis. Thus, a modifiable factor for a long-term improvement in metabolic control has been identified.
R. Hanas: Advisory Panel; Self; Abbott, Novo Nordisk A/S. Speaker’s Bureau; Self; Sanofi. Other Relationship; Self; AstraZeneca. I.I. Steineck: None. J. Anderzén: None. K. Eeg-Olofsson: None. J. Ekelund: Employee; Spouse/Partner; AstraZeneca. S. Gudbjörnsdottir: None. L. Hanberger: None. J. Nåtman: None. A. Pundziute Lyckå: None. A. Svensson: None. S. Särnblad: Advisory Panel; Self; Novo Nordisk A/S. Other Relationship; Self; Novo Nordisk A/S. K. Akesson: None.