Neither inflammatory bowel disease nor immunosuppressants are associated with an increased risk of severe COVID-19: an observational Dutch cohort study.

Conflicting data about inflammatory bowel disease [IBD] and immunosuppressants are risk factors for severe COVID-19 confuse patients and healthcare providers. Clinical reports with longer follow-up are lacking. A retrospective search was performed for severe COVID-19 (hospital admission and/or mortality) one year after the SARS-CoV-2 outbreak in an IBD cohort from one of the most affected Dutch regions. Cohort characteristics were explored by value-based healthcare data, including immunotherapy. COVID-19 cases were detected by ICD-10 codes and further examined for IBD determinants (including medication) and COVID-19 characteristics (intensive care admission, respiratory support, treatment, mortality). The national mortality register was consulted, ensuring detection of patients that died without admission. Results were compared with regional and national general population registries. The IBD cohort consisted of 1453 patients (51% Crohn's disease, 54% women, 39.9% using immunotherapy), including children. Biologics use increased during the study. Eight cases (0.55%) had severe COVID-19: seven were hospitalized (0.48%, 95% confidence interval [CI] 0.21-1.04), and two died (0.14%, CI 0.002-0.55). Six patients had comorbidity, one used immunotherapy, and four had no medication. Both deceased patients were older than 80 years, had severe comorbidity, but used no immunotherapy. Hospitalization occurred significantly more in the IBD cohort than regionally (0.18%, CI 0.17-0.19, p = 0.015), but not significantly more than nationally (0.28%, CI 0.279-0.284). Mortality was equal in IBD patients, regionally (0.11%, CI 0.10-0.12) and nationally (0.13%, CI 0.125-0.128). Neither IBD nor immunosuppressants are associated with increased risks of severe COVID-19 in an observational study with one-year follow-up.