Upper-Airway Microbiome, Mucociliary Function, and Clinical Outcomes in Bronchiectasis: Data from the EMBARC-BRIDGE...

Area of Science:

• Microbiology
• Pulmonology
• Genetics

Background:

• Infections significantly drive disease progression in bronchiectasis.
• The upper-airway microbiome influences the lower-airway microbiome composition.
• Understanding this relationship is crucial for managing bronchiectasis.

Purpose of the Study:

• To investigate the association between the upper-airway microbiome, mucociliary function, and clinical outcomes in bronchiectasis patients.
• To identify specific microbial patterns linked to disease severity and exacerbations.
• To assess the stability of the upper-airway microbiome over time.

Main Methods:

• Collected nasopharyngeal swabs from 344 bronchiectasis patients across five European centers.
• Analyzed microbiome composition, α-diversity (Chao1), and β-diversity (Bray-Curtis).
• Utilized random forest analysis and defined dysbiosis based on pathogenic taxa abundance (Pseudomonas, Haemophilus, Staphylococcus).

Main Results:

• α-Diversity significantly differed by disease severity (P=0.002).
• Distinct microbiome profiles were associated with disease severity and severe exacerbations (P=0.021 and P=0.001, respectively).
• Pseudomonas abundance correlated with severe bronchiectasis, exacerbations, and sputum Pseudomonas aeruginosa growth; dysbiosis linked to worse symptoms and outcomes.

Conclusions:

• The upper-airway microbiome composition is significantly associated with bronchiectasis severity.
• Nasopharyngeal dysbiosis is a predictor of more severe clinical outcomes and exacerbations.
• Microbiome profiles demonstrated relative stability between baseline and 1-year follow-up.