Blood eosinophil guided prednisolone therapy for exacerbations of COPD: a further analysis
To the Editor: Exacerbations of chronic obstructive pulmonary disease (COPD) are associated with significant morbidity and mortality [1]. Current guidelines advocate the use of systemic corticosteroids in addition to antibiotics to treat an exacerbation [2, 3], but these treatments are not universally effective and are not without harm [4]. Individualised treatment may, therefore, be an advance. Recently we showed that patients with a peripheral blood eosinophil count of ≥2% at the onset of an outpatient managed exacerbation respond promptly and completely to prednisolone, whereas those with a count of <2% had a higher rate of treatment failure compared with placebo [5]. Whether these findings can be replicated in a larger population, including patients hospitalised with exacerbations of COPD remains unclear. We set out to address these questions in a further analysis of randomised controlled studies comparing outcomes in patients with exacerbations of COPD treated with prednisolone or non-prednisolone (placebo or equivalent). We investigated the rates of treatment failures in patients stratified by the peripheral blood eosinophil count measured at the time of exacerbation. A literature search of the Medline, EMBASE and PubMed databases was performed using the MeSH terms: 1) chronic obstructive pulmonary disease; 2) exacerbations; 3) oral corticosteroid/prednisolone; and 4) randomised clinical trials. Six trials fulfilled these criteria and the authors were contacted about data sharing. Of these studies, the peripheral blood eosinophil count at the onset …