Oral Microbiome Diversity Predicts All-cause Mortality in the General Population: A Prospective Population-based Cohort Study

Background Increasing evidence suggests a potential link between oral microbiome diversity and the occurrence of multiple chronic extraoral diseases. However, evidence regarding oral microbiota diversity and long-term prognosis in the general population is limited. This prospective study aimed to investigate whether oral microbiome diversity is associated with all-cause mortality in the general population. Results During a mean follow-up period of 8.9 years, 429 deaths occurred. After multivariate adjustment, a negative association was observed between oral microbiome α diversity and all-cause mortality (P < 0.01). Significant differences in all-cause mortality risk were observed between the different clusters based on the oral microbiome β diversity (Log-rank P < 0.001). Subgroup analyses revealed that oral microbiome diversity was independently associated with all-cause mortality in individuals with extraoral diseases, particularly those with diabetes mellitus and hypertension. A multivariate logistic regression model demonstrated that increased dietary fiber intake and reduced antibiotic use were significantly associated with higher oral microbiome α diversity. Conclusions Higher oral microbiome diversity was significantly associated with a lower risk of all-cause mortality in the general population and in individuals with extraoral diseases, especially diabetes mellitus and hypertension. Reasonable restrictions on antibiotic use and high dietary fiber intake may increase oral microbiome diversity, thereby reducing the risk of all-cause mortality.