A Systematic Review and Meta-Analysis: Adverse Inflammatory Bowel Disease Outcomes Following Acute COVID-19

BACKGROUND AND AIMS: Respiratory viral infections have been implicated in the exacerbation of immune-mediated inflammatory diseases such as inflammatory bowel disease (IBD). To understand the impact of early SARS-CoV-2 variants on the risk of adverse IBD outcomes, we aimed to perform a meta- analysis of high-quality studies. METHODS: Cohort studies investigating adverse IBD outcomes (IBD flares, change in disease activity, change in medication, IBD-related hospitalization, and surgery) following COVID-19 were retrieved from MEDLINE and Embase. The Risk Of Bias In Nonrandomized Studies-of Exposure tool was used to assess risk of bias. Random effects model meta-analysis was used to calculate the hazard ratio (HR) for risk of adverse outcomes. Subgroup analysis was performed to estimate risk of outcomes for ulcerative colitis and Crohn's disease patients. Metaregression was performed for sex and duration of follow-up. RESULTS: Of the 3119 identified studies, 5 were included in the meta- analysis. A total of 34,977 IBD patients with COVID-19 and 53,270 IBD patients without recorded COVID-19 infection were identified. Two of the studies showed a high risk of bias. The random effects model did not show a statistically significant increase in the risk of adverse IBD outcomes following COVID infection (HR:1.05 [0.75-1.46]). There was no significant difference in adverse outcomes between Crohn's disease (HR: 0.91 [0.82-1.02]) and ulcerative colitis patients (HR: 0.83 [0.76-0.90]). Neither the proportion of male participants nor the mean duration of follow-up were found to be significant predictors of effect size. CONCLUSION: In this systematic review and meta-analysis, we find that COVID-19 did not increase the risk of adverse IBD outcomes.