The Casual Relationship Between Inflammatory Bowel Disease And Periodontitis: A Mendelian Randomization Study

Background:Observationalstudies have shown a significant association between inflammatory bowel disease and periodontitis,but it is unclear whether these associations are causal.However,observational studies are susceptible to confounding factors and reverse causality,and these limitations hinder the establishment of causal direction and causal conclusions.Therefore,we use Mendelian randomization to comprehensively evaluate the causal relationship between chronic and aggressive periodontitis and inflammatory bowel disease from a genetic perspectiveMethods:In this study,genetic variations were extracted as instrumental variables from the summary-level data of genome-wide association analyses for inflammatory bowel disease and periodontitis.The summary-level data for inflammatory bowel disease included a total of 12,882 cases and 21,770 controls,while the summary-level data for ulcerative colitis included 6,968 cases and 20,464 controls,and the summary-level data for Crohn’s disease included 5,956 cases and 14,927 controls.For periodontitis,the summary-level data included 950 cases of chronic periodontitis and 45,398 controls,and 128 cases of aggressive periodontitis and 45,622 controls.Two-sample Mendelian randomization analysis was then conductedResults:In the Mendelian randomization framework,genetic predisposition to inflammatory bowel disease and acute periodontitis was associated with an increased risk,with statistical results of(OR=1.323,P_ivw=0.016,95%CI [1.054,1.662]).However,no significant causal effect was observed in the subtypes(UC,CD→AGP)or overall IBD(including UC,CD→CP)directions,as all P-values were greater than0.05.Additionally,in the reverse causal analysis,the results showed that acute periodontitis was a risk factor for CD(OR=1.039,P_ivw=0.011,95%CI [1.009,1.069]).However,no significant causal effect was observed in the AGP→IBD or UC directions.Conclusions:Within the limitations of this Mendelian randomization study,the results support the notion that IBD increases the risk of AgP overall,while AgP increases the risk of CD.This genetic evidence confirms the causal relationship between IBD and PD and may provide meaningful guidance in clinical work...