Sputum Microbiome is Associated with 1-Year Mortality Following COPD Hospitalizations.
Am J Respir Crit Care Med. 2018 Oct 30;:
Authors: Leitao Filho FS, Alotaibi NM, Ngan D, Tam S, Yang J, Hollander Z, Chen V, FitzGerald JM, Nislow C, Leung JM, Man SFP, Sin DD
RATIONALE: Lung dysbiosis promotes airway inflammation and decreased local immunity, potentially playing a role in the pathogenesis of acute exacerbations of COPD (AECOPD). We determined the relationship between sputum microbiome at the time of AECOPD hospitalization and 1-year mortality in a COPD cohort.
METHODS: We used sputum samples from 102 patients hospitalized due to AECOPD. All subjects were followed for one year after discharge. The microbiome profile was assessed through sequencing of 16S rRNA gene. Microbiome analyses were performed according to 1-year mortality status. To investigate the effect of alpha diversity measures and taxa features on time to death, we applied Cox proportional-hazards regression models and obtained hazard ratios (HR) associated with these variables.
MEASUREMENTS AND MAIN RESULTS: We observed significantly lower values of alpha diversity (Richness, Shannon Index, Evenness, and Faith's Phylogenetic Diversity) among non-survivors (n=19, 18.6%) compared to survivors (n=83, 81.4%). Beta diversity analysis also demonstrated significant differences between both groups (adj. PERMANOVA, p=0.010). The survivors had a higher relative abundance of Veillonella; in contrast, non-survivors had a higher abundance of Staphylococcus. The adjusted HRs for 1-year mortality increased significantly with decreasing alpha diversity. We also observed lower survival among patients in whom sputum samples were negative for Veillonella (HR: 13.5, 95% CI: 4.2 - 43.9, p<0.001) or positive for Staphylococcus (HR: 7.3, 95% CI: 1.6 - 33.2, p=0.01).
CONCLUSION: The microbiome profile of sputum in AECOPD is associated with 1-year mortality and may be used to identify subjects with a poor prognosis at the time of hospitalization.
PMID: 30376356 [PubMed - as supplied by publisher]