Causal relationship between inflammatory bowel disease and gingivitis or periodontal disease:A two-sample Mendelian randomized analysis

Background:Observational studies have shown that inflammatory bowel disease(IBD),such as ulcerative colitis(UC)and Crohn dis-ease(CD),is associated with gingivitis and periodontal disease(GP).This study aims to investigate whether there is a causal relationship between IBD and GP. Methods:This study assessed the causal relationship between IBD and GP through a two-sample Mendelian randomization(MR)study.The required data were obtained through the IEU OpenGWAS project.Instrumental variable screening and the MR and sensitivity analyses were performed using the"TwoSampleMR"R package. Results:IBD,UC,and CD may have a causal effect on GP(IBD,inverse variance weighting[IVW]OR=1.05,95％Cl=1.00-1.10,P=0.03;UC,IVW OR=1.05,95％Cl=1.00-1.11,P=0.03;CD,weighted median OR=1.06,95％Cl=1.00-1.13,P=0.04;simple mode OR=1.15,95％Cl=1.02-1.31,P=0.03).Scatterplots,forest plots,and funnel plots showed a significant relationship between IBD and GP and confirmed the robustness of the model.In sensitivity testing,no horizontal pleiotropy or heterogeneity was found in this study. Conclusions:This study found a possible causal relationship between IBD(UC and CD)and GP,which deserves to be considered in clinical practice.