Incidence of Type 1 Diabetes before and During the COVID-19 Pandemic in Isfahan, Iran

Abstract

Background: Studies suggest a potential global increase in the incidence rate of type 1 diabetes (T1D) following the SARS-CoV-2 pandemic. This study aimed to assess the incidence of T1D in Isfahan Province before and during the pandemic to better understand the situation in this population. Methods: In this cross-sectional study, we determined the incidence rate of new-onset T1D for the two years preceding the COVID-19 pandemic (2018-2019) and during the two years of the pandemic (2020-2021). We also calculated incidence rates each year by sex and age groups (0–4 years, 5–9 years, 10–14 years, and 15–18 years). Results: The age-adjusted incidence rates (95 CI) of T1D in Isfahan were as follows: 16.38 (16.27-16.49) in 2018, 13.94 (13.51-14.35) in 2019, 13.17 (12.44-13.90) in 2020, and 18.09 (17.17-19.00) in 2021 per 100,000 children. The average annual percent change (APC) was 9.7, with the highest APC of 37.34 in 2021. There was no statistically significant trend in T1D incidence during the study period (P > 0.05). The frequency of diabetic ketoacidosis (DKA) was higher during the COVID-19 period in 2020 and 2021 compared to 2018, with rates of 54.89 in 2021, 52.82 in 2020, 52.68 in 2019, and 32.49 in 2018 (P < 0.005). Conclusion: This research observed an increasing incidence rate of T1D, particularly in the second year of the COVID-19 outbreak. While other studies have also reported an increase in T1D cases, the complex nature of T1D development makes it challenging to draw definitive conclusions about the impact of SARS-CoV-2 infection on T1D onset. © 2025, Mashhad University of Medical Sciences. All rights reserved.