Children with a high genetic risk of developing type 1 diabetes see an increase in islet autoantibodies, which develop against pancreatic β-cell proteins, shortly after infection with SARS-CoV-2, illustrating a temporal relationship between COVID-19 and islet autoantibodies not seen with influenza. The study was published in JAMA.
The findings came from the European Primary Oral Insulin Trial, which enrolled 1,050 infants (517 girls) aged 4 to 7 months with more than a 10% genetically defined risk of type 1 diabetes from February 2018 to March 2021. Follow-up continued through September 2022. During follow-up, children submitted blood samples for SARS-CoV-2 antibody testing.
Of 885 children who agreed to participate in the study, SARS-CoV-2 antibodies developed in 170 children at a median age of 18 months, and islet autoantibodies developed in 60 children. Six of the 60 children tested positive for islet autoantibodies and SARS-CoV-2 antibodies at the same time, and six tested positive for islet antibodies after having tested positive for SARS-CoV-2 antibodies 2 to 6 months earlier.
Children under 18 months most at risk
Overall, the incidence rate of islet autoantibodies was 3.5 (95% confidence interval [CI], 2.2 to 5.1) per 100 person-years in children without SARS-CoV-2 antibodies and 7.8 (95% CI, 5.3 to 19.0) per 100 person-years in children with SARS-CoV-2 antibodies.
The findings indicate that SARS-CoV-2 infections are associated with an increased risk of islet autoimmunity in young children.
Children younger than 18 months had an increased hazard ratio of developing islet autoantibodies after SARS-CoV-2 antibody development (hazard ratio [HR], 5.3; 95% CI, 1.5 to 18.3).
The study builds on the understanding of type 1 diabetes and COVID-19, the researchers said. Many clinicians reported a significant increase in type 1 pediatric cases early in the pandemic, and islet autoantibodies have previously been linked to viral infections. Children who develop multiple islet autoantibodies usually progress to clinical type 1 diabetes within 10 years, but this study didn't detect a relationship between islet autoantibodies and H1N1 antibodies.
"The findings indicate that SARS-CoV-2 infections are associated with an increased risk of islet autoimmunity in young children with a high genetic risk of type 1 diabetes," the authors wrote.