Bente M. Nørgård[1,2], Floor D. Zegers[1,2], Jan Nielsen[1,2], Torben Knudsen[3,4], Jens Kjeldsen[5,6]

Affiliates

Center for Clinical Epidemiology Odense University Hospital[1], Research Unit of Clinical Epidemiology Department of Clinical Research University of Southern Denmark [2], Department of Medicine Hospital of Southwest Jutland [3], Department of Regional Health Science University of Southern Denmark[4], 5: Department of Medical Gastroenterology Odense University Hospital [5], Research Unit of Medical Gastroenterology Department of Clinical Research University of Southern Denmark[6]

Abstract

Background: This study aims to determine if an infection with COVID-19 triggers disease activity in patients with inflammatory bowel disease (IBD). A redeemed prescription for steroids was used as a proxy for disease activity in a patient with IBD.
Methods: The population comprised of patients with at least one diagnosis of ulcerative colitis or Crohn’s disease before 1. March 2020 registered in Danish National Health Registries. The number of redeemed prescriptions with steroids for patients with IBD between the start of the pandemic 1 March 2020 and end of follow-up (death or 31. July 2022), was counted. The number of prescriptions was assessed before and after a first positive COVID-19 PCR-test for the COVID-19 positive patients. A random-intercept negative binomial regression model was made to compare incidence rates of the number of prescriptions before versus after a positive COVID-19 PCR-test. We calculated the incidence rate ratio (IRR) with 95% CI. Adjustment was made for sex, Charlson Comorbidity Index before first IBD-diagnosis and age on 1. March 2020.

Results: Of 60,461 IBD patients, 30,362 (50.2 %) had positive COVID-19 PCR-tests. Of these, 26,782 (88.2 %) had no redeemed prescriptions before COVID-19 infection, and 28,838 (95.0 %) had no redeemed prescriptions after COVID-19 infection. The adjusted IRRs of number of redeemed steroid prescriptions after COVID-19 infection was 0.86 (95 % CI 0.82-0.91).
Conclusion: An infection with COVID-19 did not result in a higher rate of redeemed steroid prescriptions. Based on this proxy measurement, COVID-19 did not seem to trigger disease activity in IBD patients.