Incidence, Outcomes, and Impact of COVID-19 on Inflammatory Bowel Disease

Propensity Matched Research Network Analysis

Yousaf Hadi; Parambir S. Dulai; Justin Kupec; Nabeeha Mohy-Ud-Din; Vipul Jairath; Francis A. Farraye; Gursimran S. Kochhar


Aliment Pharmacol Ther. 2022;55(2):191-200. 

In This Article

Abstract and Introduction


Background: Accurate estimates for the risk of COVID-19 in IBD, and an understanding of the impact of COVID-19 on IBD course and the risk of incident post-infectious IBD are needed.

Aims: To estimate the risk of COVID-19 in IBD and study its impact on IBD course and the risk of incident post-infectious IBD.

Methods: A retrospective propensity score matched cohort study utilising multi-institutional research network TriNetX. COVID-19 patients with and without IBD were identified to quantify the risk of COVID-19 in patients with IBD, COVID-19 outcomes in patients with IBD and the impact of COVID-19 on IBD disease course. The risk of incident post-infectious IBD in COVID-19 patients was compared to the population not infected with COVID-19 during a similar time period.

Results: Incidence rate ratio for COVID-19 was lower in IBD patients compared to the non-IBD population (0.79, 95% CI: 0.72–0.86). COVID-19-infected patients with IBD were at increased risk for requiring hospitalisation compared to non-IBD population (RR: 1.17, 95% CI: 1.02–1.34) with no differences in need for mechanical ventilation or mortality. Patients with IBD on steroids were at an increased risk for critical care need (RR: 2.22, 95% CI: 1.29–3.82). Up to 7% of patients with IBD infected with COVID-19 suffered an IBD flare 3-months post-infection. Risk for incident IBD post-COVID was lower than that seen in the non-COVID population (RR: 0.64, 95% CI: 0.54–0.65).

Conclusion: We observed no increase in risk for COVID-19 amongst patients with IBD or risk for de novo IBD after COVID-19 infection. We confirmed prior observations regarding the impact of steroid use on COVID-19 severity in patients with IBD.


Coronavirus disease-2019 (COVID-19) caused by the novel coronavirus SARS-CoV-2 has caused more than 4.1 million deaths worldwide at the time of writing.[1] The clinical course of COVID-19 is highly variable, with presentations ranging from asymptomatic infection to multi-organ failure, acute respiratory syndrome and death.[2,3]

The SARS-CoV-2 virus gains entry into hosts by binding angiotensin-converting enzyme 2 receptor, that is also expressed in the intestinal epithelium, primarily in the terminal ileum and colon, more so when inflamed.[4] Thus, comorbid inflammatory bowel disease (IBD), particularly in the setting of immunosuppression, has been postulated to alter the risk and/or disease course of COVID-19. Whether concomitant IBD increases the risk of COVID-19 or poorer outcomes for COVID-19 disease has not been sufficiently explored. Previous studies have shown that the risk of COVID-19 disease in patients with IBD is likely similar or less than the non-IBD population.[5–7] Furthermore, some studies have raised concerns for poorer outcomes of COVID-19 in IBD subgroups. While the Surveillance Epidemiology of Coronavirus Under Research Exclusion (SECURE-IBD) registry explored outcomes of COVID-19 disease in IBD patients, there were some limitations including lack of a control population or adequate matching for confounders to provide accurate estimations of risk as well as a selection bias.[8,9] In addition, the risk of an IBD flare after COVID-19 illness and any potential impact of COVID-19 disease on the risk of de novo (incident) IBD is unexplored.

We studied the relationship between COVID-19 and IBD using a large multi-institutional research network. Outcomes of COVID-19 disease in IBD were studied and compared to matched populations. Incidence of COVID-19 in patients with IBD was calculated and compared to the non-IBD population, and the relationship between COVID-19 and incident cases of IBD was explored.