Association of gut microbiota with central blood pressure and pulse pressure amplification in community-dwelling Japanese adults: the Wakayama study.

Gut microbiota has been implicated in regulating blood pressure (BP); however, its association with central hemodynamics remains scarcely investigated. This study aimed to investigate relationships between gut microbiota and both brachial and central BP, as well as pulse pressure amplification, in community-dwelling Japanese adults not taking antihypertensive medications. A cross-sectional analysis included 1 529 participants. Gut microbiota was assessed using 16S ribosomal RNA gene sequencing. Brachial and central BP were measured, and pulse pressure amplification was calculated as the ratio of brachial to central pulse pressure. Multivariable linear regression analyses evaluated associations between gut microbiota-related variables and BP parameters, adjusting for demographic and clinical covariates. Microbial diversity indices (Shannon index and microbial richness) and the ratio of Firmicutes to Bacteroidetes were not associated with any BP measures. At the genus level, no significant associations were observed with brachial BP. The relative abundance of Dorea was positively associated with central diastolic BP (standardized β = 0.068), whereas Blautia was positively associated with pulse pressure amplification (standardized β = 0.080), independent of multiple confounding factors. These associations remained significant after false discovery rate correction. Specific gut microbial genera demonstrated associations with central hemodynamic parameters rather than conventional brachial BP. These findings suggest that gut microbiota may be more closely associated with central hemodynamics and arterial functional characteristics than with conventional brachial BP.