Therapies for Inflammatory Bowel Disease Do Not Pose Additional Risks for Adverse Outcomes of SARS-CoV-2 Infection

An IG-IBD Study

Cristina Bezzio; Alessandro Armuzzi; Federica Furfaro; Sandro Ardizzone; Monica Milla; Sonia Carparelli; Ambrogio Orlando; Flavio Andrea Caprioli; Fabiana Castiglione; Chiara Viganò; Davide Giuseppe Ribaldone; Fabiana Zingone; Rita Monterubbianesi; Nicola Imperatore; Stefano Festa; Marco Daperno; Ludovica Scucchi; Antonio Ferronato; Luca Pastorelli; Paola Balestrieri; Chiara Ricci; Maria Cappello; Carla Felice; Gionata Fiorino; Simone Saibeni


Aliment Pharmacol Ther. 2021;54(11_12):1432-1441. 

In This Article


Over the past year, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has rapidly spread around the world.[1] Research into the pathology of SARS-CoV-2-induced coronavirus disease 2019 (COVID-19) has revealed that the immune system plays two crucial roles in the infection: it controls viral replication in the early stage, and it overproduces pro-inflammatory cytokines in patients who go on to develop severe disease.[2] Thus, physicians who care for patients with immune-mediated inflammatory diseases (IMID) are concerned about the impact that COVID-19 could have on these patients.

Like all IMIDs, the two main types of inflammatory bowel disease (IBD), namely ulcerative colitis (UC) and Crohn's disease, are characterised by an abnormal functioning of the innate and adaptive immune systems, leading to a chronic, progressive condition. From emerging data, the incidence and prevalence of SARS-CoV-2 infection in IBD patients are not different from those in the general population.[3–7] Additionally, the prevalence of adverse COVID-19 outcomes, namely pneumonia, hospitalisation, intensive care unit admission and death, appears to be similar to that in the general population.[4–9] Numerous studies that investigated risk factors for adverse COVID-19 outcomes in IBD patients concordantly found similarities with those in the general population, namely older age[6–12] and presence of comorbidities.[3,6,8–10,12,13] However, in the assessment of IBD-related factors, discordant results were obtained. For example, some studies reported that disease activity was a risk factors for adverse outcomes of SARS-CoV-2 infection,[9,12] while other studies identified treatment with corticosteroids,[8,11,14] aminosalicylates,[11,13] and thiopurines (alone or in combination with anti-TNF-α agents)[13] as risk factors. These discrepancies may be due to insufficient numbers of cases or differences in epidemiological methodology.

The ongoing SARS-CoV-2 vaccination program has also raised an important clinical question about the eligibility of IBD patients for priority access to primary vaccination and booster doses. On one hand, this decision could be supported by evidence of a lower serological response to vaccines or natural infection, related to either IBD itself[15] or IBD therapies, namely anti-TNF agents.[16,17] On the other hand, if priority access is granted to people at higher risk of adverse COVID-19 outcomes, should this apply to some or all IBD patients? To answer this question, this observational study investigated risk factors for adverse COVID-19 outcomes in a large, nation-wide cohort of IBD patients, and used multivariable analyses to build indices to identify patients at the relatively highest risk.