Oral microbiome diversity and all-cause mortality in hypertensive adults: findings from a nationally representative cohort

Background Oral microbiome diversity has been associated with general health. However, its association with long-term outcomes in hypertensive individuals remains unclear.Objectives This study aimed to investigate whether oral microbiome diversity is associated with all-cause mortality in hypertensive individuals.Design Data from 2,669 hypertensive individuals in the National Health and Nutrition Examination Survey (NHANES, 2009–2012) were analyzed. Oral microbiome diversity was assessed using four alpha-diversity metrics: the Simpson index, Shannon–Weiner index, Faith’s Phylogenetic Diversity, and observed amplicon sequence variants (ASVs). Weighted multivariable Cox proportional hazards regression and interaction analyses were conducted.Results During a mean follow-up of 8.61 years, 268 all-cause deaths occurred. Higher oral microbiome diversity assessed by the Simpson index (hazard ratio [HR] = 0.38; 95% confidence interval [CI], 0.20–0.75; Ptrend < 0.01) and Shannon–Weiner index (HR = 0.47; 95% CI, 0.25–0.88; Ptrend < 0.05), was significantly associated with reduction in all-cause mortality risk. A potential interaction between sex and oral microbiome diversity on mortality risk was observed.Conclusions Higher oral microbiome diversity is an independent protective factor for survival in patients with hypertension, with potential sex-specific differences in this association. These findings suggest that enhancing oral microbiome diversity may potentially help promote overall health in individuals with hypertension.