Abstract Body: Background
Several cross-sectional studies have implicated gut dysbiosis caused by an abundance of oral commensals in cardiovascular diseases. However, no previous studies have identified oral pathobiont in the gut of acute stroke patients and longitudinally investigated their clinical relevance.
Objective
This study aims to identify key oral pathobionts that induce gut dysbiosis in stroke patients and longitudinally assess the relationship between oral pathobionts in the gut and poor prognosis following stroke.
Methods
We comprehensively analyzed the 364 salivary and gut microbiomes from 189 acute stroke patients and 55 non-stroke participants from July 2020 to July 2021. Furthermore, we prospectively observed composite outcomes of mortality and cardiovascular events over a 2-year follow-up period.
Results
Streptococcus anginosus was significantly more abundant in both the saliva (median [IQR], 0.01 [0.00–0.14] vs. 0.00 [0.00–0.03], p＝0.02) and gut (0.09 [0.00–0.28] vs. 0.00 [0.00–0.02], p<0.001) in stroke compared to non-stroke counterparts. Microbial co-occurrence network analysis revealed that Streptococcus anginosus is a central hub in gut dysbiosis. After adjusting for vascular risks, Streptococcus anginosus (odds ratio 1.20, 95% confidence interval 1.06–1.36, p<0.01), Anaerostipes hadrus (0.82, [0.73–0.93], p<0.01), and Bacteroides plebeius (0.86, [0.86–0.93], p=0.01) in the gut were independent predictors of stroke. Longitudinally, Streptococcus anginosus in the gut was significantly associated with increased mortality and major cardiovascular events (p=0.04; log-rank test), whereas Anaerostipes hadrus and Bacteroides plebeius were not (p=0.45 and p=0.19).
Conclusions:
Streptococcus anginosus in the gut was identified as an oral pathobiont in gut dysbiosis and was independently associated with a higher risk of mortality and major cardiovascular events in stroke patients. Our findings suggest that Streptococcus anginosus may serve as a novel biomarker for predicting stroke and poor outcomes following stroke, highlighting its potential as a target for therapeutic intervention.