The Association Between the Eosinophilic COPD Phenotype with Overall Survival and Exacerbations in Patients on Long-Term Non-Invasive Ventilation.

BACKGROUND: Long-term non-invasive ventilation (LT-NIV) can prolong life expectancy and may reduce the number of exacerbations in patients with COPD. The eosinophilic phenotype has recently gained significant attention as a treatable trait in COPD. However, it is less known how this phenotype relates to exacerbations and mortality in patients who are set up on LT-NIV. METHODS: A total of 191 patients with COPD (65 ± 8 years, 55% women) who were setup on LT-NIV and followed-up (28/15-49/months) at our tertiary centre were analysed. The eosinophilic phenotype was defined by using an accepted cutoff for blood eosinophil count (≥300 cells/µL). RESULTS: A total of 37 patients had the eosinophilic phenotype (66 ± 9 years, 60% women). There was a higher reduction in the number of exacerbations (1.0/-1.0-3.2/ vs. 0.05/-1.4-1.63/, p < 0.01) and a trend for a reduction in the rate of hospitalisations (1.0/-1.0-2.0/ vs. 0.0/0.0-1.0/, p = 0.07) post-NIV setup in the eosinophilic group. Most importantly, patients with high eosinophil counts had longer overall survival (34/15-74/ vs. 28/15-47/ months, p = 0.02, adjusted for covariates). CONCLUSIONS: The eosinophilic COPD phenotype seems to show better clinical responses to long-term NIV than patients without this trait. Further mechanistic studies are warranted to analyse this association.