(139) Background Rates of Pediatric-Onset Type I Diabetes Before and During the COVID-19 Pandemic

Publication Number: 475

Background: Higher incidence rates (IR) of pediatric-onset type I diabetes (T1DM) during the COVID-19 pandemic have been reported; however, many reports were from small, single-center studies or limited to COVID-19-infected or vaccinated individuals. Therefore, limited data exist on the background IR of T1DM in the general pediatric population during the COVID-19 pandemic for contextualizing safety signals that may arise from COVID-19 vaccines and treatments.

Objectives: To estimate the background IR of T1DM before and during the COVID-19 pandemic

Methods: Using linked medical and pharmacy claims within the HealthVerity (HV) and Optum datasets, we constructed cohorts of patients who were < 18 years old for ≥ 1 day during the period between January 1, 2018 - July 31, 2021, regardless of COVID-19 diagnosis status. The index date was the first date when patients were < 18 years old and met other inclusion criteria. The primary endpoint was the IR of T1DM reported separately by year and by age-group (0-17, 0-11, and 12-17 years). Additionally, we evaluated the prevalence of key chronic conditions at baseline in our cohort. No statistical comparisons were made. Updated results in HV, with data through Dec 31, 2022, will be available at ICPE.

Results: We analyzed data from 8,510,627 patients in HV and 3,795,527 in Optum, with a mean age of 8.7 years (SD 4.7) in HV and 7.9 years (SD 5.6) in Optum on the index date. Optum had a greater representation of children < 1 year old compared to HV (17.4% vs. 2.3%). Females accounted for 49.1% of the cohort in HV and 48.9% in Optum. Of the chronic conditions evaluated, the most common on the index date was chronic lung disease (HV: 11.1%; Optum: 3.5%).
T1DM IRs were higher in HV vs. Optum data. In HV, T1DM IRs trended upward during the COVID-19 pandemic but were stable across the study period in Optum. Annual T1DM IRs for all patients aged 0-17, per 1,000 person-years (95% CI) during 2018-2021, were 0.31 (0.30, 0.33), 0.34 (0.32, 0.35), 0.38 (0.36, 0.40), and 0.53 (0.50, 0.56) respectively in HV and 0.18 (0.16, 0.20), 0.19 (0.17, 0.21), 0.17 (0.15, 0.19), and 0.20 (0.17, 0.23) respectively, in Optum. Qualitatively, IRs were higher among the 12-17-year-olds vs. 0-11-year-olds in HV (e.g., in 2020: 12-17: 0.47 [0.43, 0.51]; 0-11: 0.35 [0.33, 0.37]) but similar in Optum (e.g., in 2020: 12-17: 0.15 [0.11, 0.19]; 0-11: 0.17 [0.15, 0.20]).

Conclusions: In Optum, T1DM IRs were qualitatively similar before vs. during the COVID-19 pandemic and between 12-17- vs. 0-11-year-olds; in HV, IRs were higher during the pandemic and among 12-17- vs. 0-11-year-olds. This heterogeneity suggests the importance of using multiple databases to generate background rates.