Blood eosinophil count and pneumonia risk in patients with chronic obstructive pulmonary disease: a patient-level meta-analysis

Background Inhaled corticosteroids are important in the management of chronic obstructive pulmonary disease (COPD), but can slightly increase the risk of pneumonia in patients with moderate-to-severe COPD. Patients with circulating eosinophil counts of 2% or more of blood leucocytes respond better to inhaled corticosteroids than do those with counts of less than 2% and it was therefore postulated that blood eosinophil count might also have an...