The association between the oral microbiome and hypertension: a systematic review

Background: This study systematically reviewed the available evidence regarding the potential association between oral microbiota and hypertension. Methods: A comprehensive search of online databases was conducted by two independent investigators for all relevant articles. All observational studies that assessed the association between oral microbiota and hypertension were included. Quality appraisal was conducted using the NOS tool. Results: A total of 17 studies comprising 6007 subjects were included. The studies varied with respect to sample type and microbial analysis method. All studies, except one, found significant differences in microbial composition between hypertensive and normotensive subjects. However, there were substantial inconsistencies regarding the specific differences identified. Still, a few taxa were repeatedly found enriched in hypertension including Aggregatibacter, Kingella, Lautropia, and Leptotrachia besides the red complex periodontal pathogens. When considering only studies that controlled for false discovery rates and confounders, Atopobium, Prevotella, and Veillonella were identified as consistently associated with hypertension. Conclusion: There are significant differences in the oral microbiome between hypertensive and normotensive subjects. Despite the heterogeneity between the included studies, a subset of microbial taxa seems to be consistently enriched in hypertension. Further studies are highly recommended to explore this association. Registration: PROSPERO database (ID: CRD42023495005).