1193-P: Patterns of Autoimmunity in Youth with New-Onset Diabetes Mellitus during the COVID Era

Introduction: The incidence of diabetes mellitus increased globally during the COVID pandemic with changes in autoimmunity patterns reported in Europe. We sought to evaluate these patterns in our US-based patient population.

Methods: Retrospective chart review of patients 1-21 years of age diagnosed with type 1 diabetes at our institution. Patients diagnosed between 1.2017-2.2020 were categorized as pre-pandemic and those diagnosed between 3.2020-12.2022 as pandemic. Chi-square analysis was used to evaluate the difference in autoantibody patterns between these periods.

Results: During the pandemic, 385 patients were diagnosed with T1DM compared with 377 patients in the pre-pandemic period. Compared to the pre-pandemic period, the proportion of patients with positive for IA2A during the pandemic decreased from 72.5% to 63.9% (p <0.001) with associated decrease in GAD+IA2+ from 40.3% to 34.2% (p<0.001), increase in GAD+ only from 12.7% to 18.0% (p = 0.002) and increase in GAD+IAA+ from 4.2% to 6.6% (p=0.019). During the pandemic, the frequency of patients with autoimmune thyroiditis decreased from 17.8% to 13.9% (p=0.045) and the frequency of patients with positive celiac screen increased from 6.0% to 10.1% (p<0.001).

Conclusion: Our study demonstrates a shift in autoimmunity pattern, in a US population that persisted through 2022, with a decrease in IA2 positivity and autoimmune thyroid disease at presentation. Further investigation to evaluate for drivers of this change is important to improve understanding of the risk of comorbidities, particularly in those diagnosed since the onset of the COVID pandemic.