According to Lancet Respiratory Medicine, sputum eosinophil count was a better biomarker of COPD severity and exacerbations than blood eosinophil count only, Medpage Today reports.

In the analysis of data from the longitudinal, prospective SPIROMICS (Subpopulations and Intermediate Outcome Measures in COPD Study), blood eosinophil count as a single biomarker was not predictive of sputum eosinophils and was not associated with disease severity or exacerbations unless combined with sputum count.

Increased sputum eosinophil inflammation, however, was found to be associated with more severe COPD, decreased lung function, worse emphysema and air trapping, and a greater likelihood of exacerbations.