The Causal Effects of Appendicectomy on Immune Bowel Disease and Digestive Cancers: A Two-sample Mendelian randomization Study

Abstract

Abstract Background Previous observational studies have reported that appendicectomy is associated with IBD and digestive cancers. Using a two-sample mendelian randomization (MR) analysis, we aimed to investigate whether appendicectomy is causally associated with IBD and digestive cancers. Methods The instrumental variables (IVs) were obtained from public genome-wide association studies (GWAS) data. We used the inverse-variance weighted (IVW) method as the primary statistical method complemented with weighted median and MR-Egger approaches. Results The IVW method revealed that genetically determined appendicectomy did not have causal effects on IBD (P > 0.05) and digestive cancers (P > 0.05). Both complementary methods showed congruent results with those of the IVW method. Conclusion This study revealed no causal effects of appendicectomy on immune bowel disease and digestive cancers.