Patients with COPD can have persistent eosinophilia, which is associated with better COPD outcomes, according to a study published in the European Respiratory Journal. Authors determined eosinophil was found in the blood of 1,483 participants with COPD between 40 to 75 years old.

The researchers found that 37.4% of these patients exhibited high levels of eosinophils (2% or higher). When they compared these patients’ respiratory capacity against patients with eosinophil levels below 2% or with intermittent eosinophilia, they observed high eosinophil counts are associated with improved lung function.