Severe COVID-19 in inflammatory bowel disease patients in a population-based setting

Objective Data on the course of severe COVID-19 in inflammatory bowel disease (IBD) patients remains limited. We aimed to determine the incidence rate and clinical course of severe COVID-19 in the heavily affected South-Limburg region in the Netherlands. Methods All COVID-19 patients admitted to the only two hospitals covering the whole South-Limburg region between February 27, 2020 and January 4, 2021 were included. Incidence rates for hospitalization due to COVID-19 were determined for the IBD (n = 4980) and general population (n = 597,184) in South-Limburg. Results During a follow-up of 4254 and 510,120 person-years, 20 IBD patients (0.40%; 11 ulcerative colitis (UC), 9 Crohn's disease (CD)) and 1425 (0.24%) patients from the general population were hospitalized due to proven COVID-19 corresponding to an incidence rate of 4.7 (95% Confidence interval (CI) 3.0-7.1) and 2.8 (95% CI 2.6-2.9) per 1000 patient years, respectively (Incidence rate ratio: 1.68, 95% CI 1.08-2.62, p = 0.019). Median age (IBD: 63.0 (IQR 58.0-75.8) years vs. general population: 72.0 (IQR 62.0-80.0) years, p = 0.10) and mean BMI (IBD: 24.4 (SD 3.3) kg/m(2) vs. general population 24.1 (SD 4.9) kg/m(2), p = 0.79) at admission were comparable in both populations. As for course of severe COVID-19, similar rates of ICU admission (IBD: 12.5% vs. general population: 15.7%, p = 1.00), mechanical ventilation (6.3% vs. 11.2%, p = 1.00) and death were observed (6.3% vs. 21.8%, p = 0.22). Conclusion We found a statistically significant higher rate of hospitalization due to COVID-19 in IBD patients in a population-based setting in a heavily impacted Dutch region. This finding reflects previous research that showed IBD patients using systemic medication were at an increased risk of serious infection. However, although at an increased risk of hospitalization, clinical course of severe COVID-19 was comparable to hospitalized patients without IBD.