The Relationship between Platelet Count and Host Gut Microbiota: A Population-Based Retrospective Cross-Sectional Study.

Platelet count reflects the severity and prognosis of multiple diseases. Additionally, alterations in gut microbiota have been linked to several chronic diseases. The purpose of this study was to investigate the association between gut microbiota and platelet count. We selected 1268 subjects with fecal 16S RNA gene sequencing data from a Healthcare Screening Center cohort. Based on the third quartile of platelets (277 × 10⁸/L), we compared the gut microbiota between the upper quartile ( n = 321) and lower three quartiles groups ( n = 947). The upper quartile group had lower alpha diversity based on observed amplicon sequence variants ( q = 0.004) and phylogenetic index ( q < 0.001) than the lower three quartiles group. Significant differences were also found in the weighted UniFrac distance ( q = 0.001) and Jaccard dissimilarity ( q = 0.047) beta diversity measures between the two groups. Compared with the lower three quartiles group, the upper quartile group exhibited decreased relative abundances of the genus Faecalibacterium , which was also inversely correlated with the platelet count. Increased platelet count was associated with reduced diversity in gut microbiota and lower abundances of Faecalibacterium with beneficial gut bacteria spices F. prausnitzii , suggesting that an increased platelet count, even within normal range, may adversely affect gut microbial diversity and composition.