ABSTRACT
Background: Inflammatory bowel disease (IBD) patients undergoing treatments that act on the inmune system and present an increased risk of infections. For this reason, we could consider that these patients may have an increased risk of severe SARS-CoV-2 infection, however, it remains unclear. We aimed to analyze the cumulative incidence, the severity of the infection and its influence on the natural history of IBD in patients under biological treatment and also evaluating the possible differences with another group without these therapy. Methods: Retrospective observational study about our IBD patients followed from March 2020 to January 2021 divided into two groups: patients on treatment with biological drugs (anti-TNF, vedolizumab, ustekinumab and tofacitinib) and patients without biological drugs (thiopurines or 5-ASA). We evaluated: the cumulative incidence in 10 months for COVID-19 in the 2 cohorts;clinical variables considered risk factors for the infection, the infection severity and influence on the course of IBD employing Harvey-Bradshaw index in Crohn's disease and Mayo partial index in ulcerative colitis before and after infection. Results: It collected 755 IBD patients. 89 were infected by SARSCOV-2, 43 in the biological group and 46 in non biological group. The cumulative incidence in 10 months was 10.85% in the first group (figure 1) and 12.81% in the second group with no significant differences. We verified comparability of the groups discarded the existence of statistical differences in all of the risk factors (sex, age, hypertension, diabetes, dyslipidemia, cardiovascular disease and BMI). In most cases, the infection was mild (94.4%) and the required treatment was symptomatic in 86.4% of the total (Figure 2), without significant differences between groups. Pneumonia was diagnosed in 5 patients, whose required hospital admission (3 belonged to the biological group and 2 to the other). The maximum respiratory support required was FIO2 36%, no patient required admission to ICU and there were no deaths. Additionally, the course of IBD was not affected because of COVID-19, considering no significant differences were observed in clinical scores in each group before and after infection, even taking into account 14 patients discontinued biological therapy temporarily during infection. Conclusion: Our study suggests that IBD patients under biological therapy do not have an increased incidence of SARS-COV-2 infection and also do not have a higher risk of severe disease than IBD patients without this therapy. Furthermore, COVID-19 does not affect the natural history of IBD. These data go in the same direction as those published to date, however, we need multicentre registries with a larger sample size in the future.