Background and Aims As no population-based study has investigated the susceptibility and disease course of COVID-19 among patients with inflammatory bowel diseases (IBD), we aimed to investigate this topic in a population-based setting. Methods Two cohorts were investigated. First, a nationwide cohort of all IBD patients diagnosed with COVID-19 was prospectively followed to investigate the disease courses of both diseases. Second, within a population-based cohort of 2.6 million Danish citizens, we identified all individuals tested for SARS-CoV-2 to determine the occurrence of COVID-19 among patients with and without IBD and other immune-mediated inflammatory diseases (IMIDs). Results Between January 28, 2020 and June 2, 2020, a total of 76 IBD patients with COVID-19 were identified in the national cohort and prospectively followed for 35 days (interquartile range (IQR): 25-51). A large proportion (n=19;25%) required a COVID-19-related hospitalization for seven days (IQR: 2-8.5) which was associated with being 65 years or older (odds ratio (OR)=23.80 (95% confidence interval (CI) 6.32-89.63), p<0.01) and presence of any non-IMID comorbidity (OR=8.12 (95% CI 2.55-25.87), p<0.01), but not use of immunomodulators (p=0.52) or biologic therapies (p=0.14). In the population-based study, 8,476 of 231,601 (3.7%) residents tested positive for SARS-CoV-2; however, the occurrence was significantly lower among patients with IBD (62 of the 2,486 patients=2.5%, p<0.01) and other IMIDs (531 of 16,492 patients=3.2%, p<0.01) as compared to patients without IMIDs. Conclusion Patients with IMIDs, including IBD, had a significantly lower susceptibility to COVID-19 than patients without IMIDs and neither immunosuppressive therapies nor IBD activity were associated with the disease course of COVID-19.

Background Limited data exist regarding the disease course of coronavirus disease 2019 (COVID-19) and its relationship with immunosuppressants among patients with immune-mediated inflammatory diseases (IMIDs). Therefore, this study aims to investigate the association between COVID-19, frequent rheumatological, dermatological, gastrointestinal, and neurological IMIDs and immunosuppressants. Methods We conducted a Danish population-based cohort study including all residents living within Capital Region of Denmark and Region Zealand from January 28th, 2020 until September 15th, 2020 with the only eligibility criterion being a test for SARS-CoV-2 via reverse transcription–polymerase chain-reaction. Main outcomes included development of COVID-19, COVID-19-related hospitalization and mortality. Results COVID-19 was less common among patients with IMIDs than the background population (n = 328/20,513 (1.60%) and n = 10,792/583,788(1.85%), p < 0.01, respectively). However, those with IMIDs had a significantly higher risk of COVID-19-related hospitalization (31.1% and 18.6%, p < 0.01, respectively) and mortality (9.8% and 4.3%, p < 0.01, respectively), which were associated with patients older than 65 years, and presence of comorbidities. Furthermore, systemic steroids were independently associated with a severe course of COVID-19 (Odds ratio (OR) = 3.56 (95%CI 1.83–7.10), p < 0.01), while biologic therapies were associated with a reduced risk hereof (OR = 0.47 (95%CI 0.22–0.95), p = 0.04). Patients suspending immunosuppressants due to COVID-19 had an increased risk of subsequent hospitalization (OR = 3.59 (95%CI 1.31–10.78), p = 0.02). Conclusion This study found a lower occurrence, but a more severe disease course, of COVID-19 among patients with IMIDs, which was associated with the use of systemic steroids for IMIDs and suspension of other immunosuppressants. This study emphasizes the importance of weighing risks before suspending immunosuppressants during COVID-19.