Causal Associations Between Ulcerative Colitis and COVID-19: A Bidirectional Mendelian Randomization Study

Abstract

Abstract Background Corona Virus Disease 2019(COVID-19) has put human health and medical resources under strain since 2019. However, it’s still equivocal whether ulcerative colitis (UC) and COVID-19 have a bidirectional causal relationship, so we attempted to clarify this issue using two-sample mendelian randomization (two-sample MR) analysis. Methods To explore the relationship between ulcerative colitis and COVID-19, we obtained summary statistics from the GWAS database and used single nucleotide polymorphisms (SNPs) as a genetic tool. The inverse-variance weighted (IVW) method was chosen as the primary analytical method for two-sample Mendelian randomization analysis, complemented by a combination of MR-egger. Further validation using sensitivity analysis such as Q-test, MR-PRESSO, MR-Egger intercepts method. Result All forward MR analyses demonstrated that UC has a significant susceptibility and severity to COVID-19, 1. COVID-19 vs population: IVW (OR = 1.053; CI, 1.012–1.096; P = 0.009) and MR Egger (OR = 1.015; CI, 0.946–1.089; P = 0.672). 2.hospitalized vs population: IVW (OR = 1.080; CI, 1.004–1.162; P = 0.037) and MR Egger (OR = 1.009; CI, 0.882–1.153; P = 0.898). 3. very severe respiratory confirmed vs population: IVW (OR = 1.187; CI, 1.018–1.384; P = 0.027) and MR Egger (OR = 1.104; CI, 0.801–1.521; P = 0.554). In the bidirectional MR study, the P values (P > 0.05) obtained by several methods were not statistically significant. Conclusion There is significant evidence that UC is both a risk factor for COVID-19 and may increase the risk of COVID-19. However, there is no reverse causal relationship between the two diseases.