Causal relationship between oral diseases and hypertension: a Mendelian randomization study

Current evidence supports the potential association between several common oral diseases and hypertension. The aim of the research is to clarify the causal relationship between these oral diseases and hypertension using Mendelian randomization (MR) analysis. Single nucleotide polymorphisms (SNPs) related to five oral traits (periodontitis, bleeding gums, loose teeth, periapical abscess and dental caries) were obtained from GWAS catalog, while those associated with hypertension (essential and secondary) were extracted from the FinnGen database. The SNPs were employed as instrumental variables (IVs) in the MR analysis. Assorted methods were applied, and inverse variance-weighted (IVW) analytical method was prioritized. Sensitivity analyses including MR-PRESSO method, MR Egger intercept test, Cochran's Q test, leave-one-out analysis and MR Steiger test were conducted. Our analysis identified the potential causal relationship between dental caries and essential hypertension. The forward MR analysis demonstrated a significant causal effect of dental caries on essential hypertension (OR = 1.036, 95%CI: 1.012-1.059, P = 0.003). The reverse analysis also indicated a significant causal effect (OR = 1.160, 95%CI: 1.016-1.323, P = 0.028). Additionally, we observed a causal effect of bleeding gums on essential hypertension (OR = 1.145, 95%CI: 1.019-1.288, P = 0.023). These findings support the potential causality between specific oral diseases and essential hypertension.