BACKGROUND AND AIMS: The health consequences of the coronavirus disease 2019 (COVID-19) among patients with ulcerative colitis (UC) and Crohn's disease (CD) remain largely unknown. We aimed to investigate outcomes and long-term effects of COVID-19 in patients with UC or CD.

METHODS: We conducted a prospective, population-based study covering all Danish patients with CD or UC and confirmed COVID-19 between January 28th, 2020 and April 1st, 2021, through medical records and questionnaires.

RESULTS: All 319 patients with UC and 197 patients with CD who developed COVID-19 in Denmark were included in this study and compared with the Danish background population with COVID-19 (N=230,087). A significantly higher risk of COVID-19-related hospitalization was observed among patients with UC (N=46(14.4%), RR=2.49 (95%CI 1.91-3.26)) and CD (N=24(12.2%), RR=2.11 (95%CI 1.45-3.07)) as compared with the background population (N=13,306 (5.8%)). A similar pattern was observed for admission to intensive care (UC: N=8(2.51%), RR=27.88 (95%CI 13.88-56.00); CD: N=3 (1.52%), RR=16.92 (95%CI 5.46-52.46)). After a median of 5.1 months (IQR 4.5-7.9), 58 (42.3%) and 39 (45.9%) patients with UC and CD, reported persisting symptoms which were independently associated with discontinuation of immunosuppressive therapies during COVID-19 (OR=1.50 (95%CI 1.07-10.22), p=0.01) and severe COVID-19 (OR=2.76 (95%CI 1.05-3.90), p=0.04), but not with age nor presence of comorbidities.

CONCLUSION: In this population-based study of 516 patients with IBD and COVID-19, 13.6% needed hospitalization and 2.1% required intensive care. Furthermore, sequelae were frequent affecting 43.7% of COVID-19 infected. These findings might have implications for planning the healthcare of patients in the post-COVID-19 era.