Loss of Airway Phylogenetic Diversity Is Associated with Clinical and Pathobiological Markers of Disease Development in COPD.

The airway microbiome has the potential to shape COPD pathogenesis, but its relationship to outcomes in milder disease is unestablished. Identify sputum microbiome characteristics associated with markers of COPD in participants of the SubPopulations and InteRmediate Outcome Measures of COPD Study (SPIROMICS). Sputum DNA from 877 participants were analyzed using 16S rRNA gene sequencing. Relationships between baseline airway microbiota composition and clinical, radiographic and muco-inflammatory markers, including longitudinal lung function trajectory, were examined. Participant data represented predominantly milder disease (GOLD 0-2: N=732/877). Phylogenetic diversity (range of different species within a sample) correlated positively with baseline lung function, declined with higher GOLD stage, and correlated negatively with symptom burden, radiographic markers of airway disease, and total mucin concentrations (p<0.001). In co-variate adjusted regression models, organisms robustly associated with better lung function included members of In SPIROMICS baseline airway microbiota features demonstrate divergent associations with better or worse COPD-related outcomes.