Background: The impact of COVID-19 on gastrointestinal (GI) outcomes in children during the post-acute and chronic phases of the disease is not well understood. Methods: We conducted a retrospective cohort study across twenty-nine healthcare institutions from March 2020 to September 2023, including 413,455 pediatric patients with confirmed SARS-CoV-2 infection and 1,163,478 controls without infection. Infection was confirmed via polymerase chain reaction (PCR), serology, antigen tests, or clinical diagnosis of COVID-19 and related conditions. We examined the incidence of predefined GI symptoms and disorders during the post-acute (28 to 179 days post-infection) and chronic (180 to 729 days post-infection) phases. The adjusted risk ratios (aRRs) were calculated using stratified Poisson regression, with stratification based on propensity scores. Results: Our cohort comprised 1,576,933 patients, with females representing 48.0% of the sample. The analysis revealed that children with SARS-CoV-2 infection had an increased risk of developing at least one GI symptom or disorder in both the post-acute (8.64% vs. 6.85%; aRR 1.25, 95% CI 1.24-1.27) and chronic phases (12.60% vs. 9.47%; aRR 1.28, 95% CI 1.26-1.30) compared to uninfected peers. Specifically, the risk of abdominal pain was higher in COVID-19 positive patients during the post-acute phase (2.54% vs. 2.06%; aRR 1.14, 95% CI 1.11-1.17) and chronic phase (4.57% vs. 3.40%; aRR 1.24, 95% CI 1.22-1.27). Interpretation: Children with a history of SARS-CoV-2 infection are at an increased risk of GI symptoms and disorders during the post-acute and chronic phases of COVID-19. This highlights the need for ongoing monitoring and management of GI outcomes in this population.

Dr. Becich reports PCORnet funding as MPI for the PaTH Clinical Research Network. All other authors have no conflicts of interest to report.

This research was funded in part by the National Institutes of Health (NIH) Agreement OTA OT2HL161847-01 as part of the Researching COVID to Enhance Recovery (RECOVER) Research Initiative.

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This study was approved by the University of Pennsylvania institutional review board (No. 851604) with a waiver of informed consent.

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