COVID-19 vaccination in adolescents and young adults with type 1 diabetes: Glycemic control and side effects

Two vaccines against SARS-CoV-2 are approved by the World Health Organization (WHO) for minors aged 12 years and over. Currently, people with both type 1 diabetes (T1D) and type 2 diabetes (T2D) are prioritized for vaccination.

To evaluate possible glycemic control modification, insulin dose adjustment and adverse effects after COVID-19 vaccination in young T1D individuals, users of different technology levels.

Thirty-nine T1D individuals, who received a whole vaccination cycle of either Moderna or Pfizer- BioNTech vaccines, were enrolled, 24 of whom using advanced hybrid closed loop systems (AHCLs) and 15 using intermittently scanned continuous glucose monitoring (isCGM). Symptoms after each dose and the following variables were considered: time in range 70-180 mg/dl (TIR), time in different glucose ranges, mean glucose levels, coefficient of variation (CV), total daily dose (TDD) and bolus proportion RESULTS: No significant differences in TIR, time in different glucose ranges, mean glucose levels, TDD, bolus proportion, were observed before and after any dose nor before and after the whole vaccination cycle. CV was significantly lower after the whole vaccination cycle (CV pre-vaccination 35.1 ± 6.9% vs. CV post-vaccination 33.5 ± 6.3%; p 0.031) in subjects treated by AHCLs. Side effects after the vaccination were mild and more frequent after the second dose. No severe adverse reactions were reported.

COVID-19 vaccination was safe and not associated with significant perturbation of glycemic control in adolescents and young adults with T1D. This information could be of clinical use when counseling families about SARS-CoV-2 vaccination in young people with T1D.