Background Oral microbiota are thought to influence blood pressure (BP) regulation. However, epidemiological data supporting this hypothesis are limited. We examined associations between oral microbiota, BP, and incident hypertension in postmenopausal women. Methods and Results Baseline (1997-2001) examinations were completed on 1215 women (mean age, 63 years) during which subgingival plaque was collected, BP was measured, and medical and lifestyle histories and medication inventory were obtained. Microbiome composition of subgingival plaque was measured using 16S ribosomal RNA gene amplicon sequencing. Baseline measured BP was defined as normotensive (systolic <120 mm Hg and diastolic <80 mm Hg, no BP medication use; n=429); elevated (systolic ≥120 mm Hg or diastolic ≥80 mm Hg, no medication use; n=306); or prevalent treated hypertension (history of physician diagnosis treated with medications; n=480). Incident hypertension (375 cases among 735 without baseline treated hypertension) was defined as newly physician-diagnosed hypertension treated with medication reported on annual health surveys (mean follow-up, 10.4 years). Cross-sectional analysis identified 47 bacterial species (of 245 total) that differed significantly according to baseline BP status (P<0.05). Prospective analysis identified 15 baseline bacterial species significantly (P<0.05) associated with incident hypertension: 10 positively (age-adjusted hazard ratios [HRs], 1.10-1.16 per SD in bacterial abundance) and 5 inversely (HRs, 0.82-0.91) associated. Associations were materially unchanged after further adjustment for demographic, clinical, and lifestyle factors; were similar when analysis was restricted to the normotensive group; and were of consistent magnitudes between strata of baseline age, smoking, body mass index, and BP categories. Conclusions Specific oral bacteria are associated with baseline BP status and risk of hypertension development among postmenopausal women. Research to confirm these observations and elucidate mechanisms is needed.
Keywords: epidemiology; hypertension; menopause; microbiome; women’s health.