Inflammatory Bowel Disease Incidence following COVID-19: A Systematic Review and Meta-Analysis

Background: A surge of cases of autoimmune and inflammatory diseases, such as inflammatory bowel disease (IBD), have been reported after coronavirus disease 2019 (COVID-19). Objective: The objective of this study was to assess whether COVID-19 has a role in IBD risk. Methods: We searched MEDLINE (PubMed), Cochrane Library and OpenGrey databases up to October 30, 2025, for studies evaluating the incidence of IBD following COVID-19 infection (PROSPERO ID: CRD42024534916). Results: After a full-text review of 84 manuscripts, a total of 8 studies were used in the qualitative analysis. The studies were conducted between 2023 and 2024 and included in total 28,659,801 people, 8,560,826 of which were previously infected with COVID-19 and 20,098,975 that served as healthy controls. The results from the pooled synthesis of 6 studies indicate a 39% higher incidence of IBD in people that were previously infected with COVID-19 (risk ratio [RR] 1.39, 95% CI: [1.12–1.74], p = 0.003, I2 = 97%). Furthermore, from the pooled analysis of 4 eligible studies, a higher incidence of new ulcerative colitis cases following COVID-19 was observed (RR 1.25, 95% CI: [1.17–1.33], p < 0.00001, I2 = 0%). On the contrary, no difference was observed in Crohn’s disease incidence between COVID-19 and non-COVID-19 patients (RR 1.23 95% CI: [0.88, 1.72], p = 0.22, I2 = 91%). Conclusions: The findings of the present meta-analysis suggest an increased risk of IBD after COVID-19 infection. Although this is more evident regarding ulcerative colitis, we believe that the available outcomes arising from future studies will clarify the real incidence of Crohn’s disease following COVID-19 infection.