Shin SH, et al. - In this study including 299 chronic obstructive pulmonary disease (COPD) patients from the Korean Obstructive Lung Disease cohort with at least two blood eosinophil measurements, researchers assessed the stability of blood eosinophils and its relation to clinical outcomes. They determined the link between eosinophil changes and all-cause mortality in these subjects stratified according to a cut-off of 300 cells/μL. They observed a better survival rate among patients with persistently high blood eosinophils vs those with persistently low blood eosinophils. Overall, in COPD, outcome prediction may be aided by serial follow-up of blood eosinophils.