Across an internal ischemic stroke cohort and several public datasets spanning myocardial infarction, stroke, and age-stratified populations, recurring genera emerged as candidate overlapping features: pathobionts Escherichia-Shigella and Klebsiella appeared repeatedly elevated, while short-chain fatty acid (SCFA)-producing genera — Faecalibacterium, Blautia, and Roseburia — showed non-uniform patterns. Lachnoclostridium and Bacteroides displayed opposite abundance gradients in selected cross-dataset comparisons. Critically, no taxon survived false-discovery-rate correction in the internal cohort, positioning every observation as descriptive hypothesis generation rather than confirmed signal.
The finding that vascular disease and aging may share an ecological microbiome signature aligns with a growing body of literature linking gut dysbiosis to systemic inflammation, endothelial dysfunction, and immunosenescence — plausible mechanistic bridges between stroke, infarction, and biological aging. The SCFA producers identified here are consistently depleted in cardiovascular and aging cohorts globally, reinforcing their potential role as longevity-relevant commensals. However, the limitations here are substantial: the internal cohort is small, datasets were not harmonized, and no metabolite, inflammatory marker, or intestinal permeability data accompany the compositional profiles. Cross-sectional and observational by design, causality is entirely unresolved. For practitioners and health-conscious adults, this is early-stage cartography — identifying terrain worth exploring — rather than actionable microbiome guidance. Confirmatory metagenomic and metabolomic longitudinal studies in larger, harmonized cohorts are essential before any clinical inference is warranted. Incremental at best.