Relationship between periodontitis and oral cancer: A two-sample Mendelian randomisation study

Background: Reports suggest an association between periodontitis and oral cancer. Therefore, this study used a Mendelian randomisation analysis to investigate whether a causal relationship exists between periodontitis and oral cancer and whether periodontitis is a reliable early indicator of oral cancer. Methods Publicly available genome-wide association study data were used to perform a two-sample, two-way Mendelian randomisation (MR) analysis primarily via inverse variance weighting (IVW). Complementary methods were used to detect and correct the effects of horizontal polytropy. Results Acute periodontitis (IVW [odds ratio (OR) = 0.999, 95% confidence interval (CI) = 0.999–1.000, P = 0.972]; MR-Egger [OR = 1.000, 95% CI = 0.999–1.000, P = 0.843]; and weighted median [OR = 1.000, 95%CI = 0.999–1.000, P = 0.947]) and chronic periodontitis (IVW [OR = 0.999, 95% CI = 0.999 − 1.000, P = 0.725; MR-Egger [OR = 1.000, 95% CI = 0.998–1.000, P = 0.245); and weighted median [OR = 1.000, 95% CI = 0.999–1.000, P = 0.834]) did not affect oral cancer. Conclusions Our MR analysis did not support a causal relationship between periodontitis and oral cancer, providing a clear reference for clinicians.