Patterns of incidence and characteristics of youth with new-onset diabetes mellitus during the COVID era

Objectives: The incidence of diabetes mellitus (DM) in children, adolescents, and young adults has been on the rise for many decades. The COVID-19 pandemic has been associated with a dramatic increase in new cases of pediatric DM and a shift in the seasonal pattern of incidence. We aimed to determine the incidence of DM and its subtypes during the COVID-19 pandemic (2020–2022) and pre-pandemic (2017–2019). We sought to assess for a difference in seasonality and temporal pattern of new-onset DM between the two periods and aimed to describe and compare the clinical characteristics of the patients diagnosed during this time. Material and Methods: In this retrospective chart review, data were collected from medical records for all patients aged 1–21 years diagnosed with DM at our center between January 1, 2017 and December 31, 2022. Results: The incidence of DM at our center increased 38% during the pandemic (incidence rate ratio [IRR] 1.38, 95% confidence interval; [CI] 1.20–1.58). The incidence of type 1 diabetes (T1D) increased 11% (IRR 1.11, 95% CI 1.01–1.23) and the median body mass index percentile increased for those diagnosed during the pandemic ( P = 0.012). The incidence of type 2 diabetes (T2D) increased 238% (IRR 3.38, 95% CI 2.17–5.28) during the pandemic, with the highest rate of diagnosis in a younger age group ( P = 0.015). The pattern of incidence of T1D shifted from lowest in the summer pre-pandemic to highest in the summer during the pandemic (IRR 1.82, 95% CI 1.22–2.72). The overall incidence trend for DM, T1D, and T2D, peaked in spring 2021 and then declined until it stabilized in summer 2022. Conclusion: Our study showed a persistent increase in the incidence of both T1D and T2D in the pediatric population during the pandemic. Those diagnosed with T2D during the pandemic were younger than those diagnosed in the pre-pandemic period. There was a shift in seasonal pattern of T1D incidence during the pandemic with the highest rates of incidence during the summer. Further studies are needed to evaluate the underlying mechanisms of the persistent increase in incidence.