Periodontitis and Chronic Obstructive Pulmonary Disease: A bidirectional Mendelian randomization study

Objective: Observational studies have suggested an association between chronic periodontitis (CP) and chronic obstructive pulmonary disease (COPD). This study aimed to determine whether there is a causal relationship between CP and COPD incidence. Design: Two-sample Mendelian Randomization (MR) analysis using summary statistics from two genome-wide association studies (GWASs) of European ancestry. Single nucleotide polymorphisms (SNPs) associated with COPD were obtained from the FinnGen database, which included 16,380,382 SNPs. The diagnosis of COPD was based on the Global Initiative for Chronic Obstructive Lung Disease (GOLD 2023). We also obtained SNPs associated with CP from the FinnGen database, which included 16,380,378 SNPs. Results: Sixteen eligible SNPs were extracted to analyze the causal effect of CP on COPD incidence. There was no causal correlation between CP and COPD using the inverse varianceweighted method (IVW) (OR=0.97, 95%CI= 0.91-1.05; p=0.482). Seven eligible SNPs were extracted to analyze the causal effect of COPD on CP incidence. Again, there was also no causal correlation between using IVW (OR=1.09, 95%CI=0.93-1.28; p=0.279). Conclusion: We did not demonstrate a causal relationship between genetically predicted CP and COPD, or between genetically predicted COPD and CP.