Abstract
AIMS: We analysed type 1 diabetes incidence in individuals aged 0-24 years from 2008 to 2021, with a focus on age at onset and potential changes during the COVID-19 pandemic. METHODS: Type 1 diabetes incidence was assessed using insulin prescriptions from the Prescribed Drug Register. One or more prescriptions defined a case in males; three or more were required in females. Data were stratified into 5-year age groups and analysed over the 2008-2021 period. RESULTS: Type 1 diabetes incidence increased by 12% in individuals aged 0-24 years in 2021 compared to 2008-2019. The highest 2021 incidence was observed in the 0-4, 5-9 and 20-24 age groups. The 10-14 group consistently had the highest rates overall, followed by 5-9, 15-19, 20-24 and 0-4. Incidence was stable prepandemic, and a significant decline in age at onset was observed over time. CONCLUSIONS: A shift in the age of onset of type 1 diabetes towards younger ages was observed between 2008 and 2021. The increased incidence in 2021 could be influenced by a possible delayed effect of the widespread SARS-CoV-2 infections during the COVID-19 pandemic.