Association between the oral microbiota and hyperlipidemia: evidence from a national cross-sectional study

Oral and gut microbiota interact in the pathogenesis of metabolic diseases. However, the associations between the oral microbiome and host lipid metabolism remain unclear. This study aimed to explore the relationship between metabolic syndrome and the oral microbiome.

Participants from the 2009-2012 National Health and Nutrition Examination Survey database were analyzed. Correlations between alpha diversity and hyperlipidemia, as well as blood lipid levels, were examined. Principal coordinate analysis and permutational multivariate analysis of variance were used to determine differences in microbial composition between groups. Linear discriminant analysis effect size (LEfSe) analysis identified key microbial taxa associated with hyperlipidemia. Cox regression and Kaplan‒Meier methods were applied for survival analyses. Functional Annotation of Prokaryotic Taxa and mediation analyses were used to explore the role of microbial functions in microbiome-mediated hyperlipidemia risk.

A total of 3104 participants were included, with 2215 diagnosed with hyperlipidemia. Multivariate linear regression revealed significant correlations between alpha diversity and total cholesterol and low-density lipoprotein levels (P < 0.017). Cox regression indicated that higher oral microbial alpha diversity was associated with a lower risk of cardiovascular mortality (P < 0.017). Beta diversity analysis revealed distinct oral microbial profiles between hyperlipidemic and non-hyperlipidemic individuals (P < 0.017). LEfSe analysis identified Prevotella and Parvimonas as key genera enriched in the oral microbiota of hyperlipidemic participants. Sulfur metabolism partially mediated the association between Parvimonas and hyperlipidemia.

The oral microbiota is closely associated with host lipid metabolism. Prevotella and Parvimonas exhibit higher oral abundances in hyperlipidemic individuals, with Parvimonas abundance directly correlated with blood lipids. Parvimonas may increase hyperlipidemia risk via sulfur metabolism. Further studies are needed to elucidate the underlying mechanisms, which could serve as effective targets for hyperlipidemia management.