Dexmedetomidine modulates gut microbiota and improves long-term survival in sepsis patients with pre-existing malignancies: a propensity-matched analysis.

Summary

In a multicenter, propensity-matched cohort of ventilated adults with sepsis, dexmedetomidine sedation was associated with significantly lower 5-year mortality versus propofol (HR 0.64). A pre-specified microbiome subcohort suggested a shift toward a more symbiotic gut community, with pronounced benefits in patients with malignancies or prior antibiotic exposure.

Key Findings

• Dexmedetomidine sedation was associated with lower 5-year mortality compared with propofol after 1:1 propensity matching (HR 0.64, 95% CI 0.52-0.79).
• Benefits were more pronounced in patients with pre-existing malignancies and those with high prior antibiotic exposure (proxy for dysbiosis).
• 16S rRNA profiling in a pre-specified subcohort indicated a shift toward a more symbiotic gut microbiome under dexmedetomidine.

Clinical Implications

Consider dexmedetomidine as a preferred sedative in ventilated sepsis, especially with malignancy or dysbiosis risk, while awaiting RCT confirmation. Monitor microbiome-disrupting factors (e.g., prolonged antibiotics) when choosing sedation.

Limitations

• Retrospective observational design with potential residual confounding and indication bias.
• Microbiome subcohort size and detailed sequencing outcomes not fully reported in the abstract.

Future Directions

Prospective randomized trials comparing dexmedetomidine vs propofol with embedded microbiome and metabolomic profiling to validate causality and define responsive subgroups.