Relationship between blood eosinophils, clinical characteristics, and mortality in patients with COPD

• Main Authors: Zysman M, Deslee G, Caillaud D, Chanez P, Escamilla R, Court-Fortune I, Nesme-Meyer P, Perez T, Paillasseur JL, Pinet C, Jebrak G, Roche N, Burgel PR
• Format: Article
• Language: English
• Published: Dove Medical Press 2017-06-01
• Series: International Journal of COPD
• Subjects: COPD; eosinophils; survival; exacerbations; quality of life
• Online Access: https://www.dovepress.com/relationship-between-blood-eosinophils-clinical-characteristics-and-mo-peer-reviewed-article-COPD

Maeva Zysman,1 Gaëtan Deslee,2 Denis Caillaud,3 Pascal Chanez,4 Roger Escamilla,5 Isabelle Court-Fortune,6 Pascale Nesme-Meyer,7 Thierry Perez,8 Jean-Louis Paillasseur,9 Christophe Pinet,10 Gilles Jebrak,11 Nicolas Roche,12,* Pierre-Régis Burgel12,* On behalf of the Initiatives BPCO (broncho-pneumopathie chronique obstructive) Scientific Committee and Investigators 1Pulmonary Dpt, Nancy, Inserm U955, team 04, Créteil, France; 2Pulmonary Dpt, Maison Blanche University Hospital, INSERM U903, Reims, France; 3Pulmonary Dpt, Gabriel Montpied University Hospital, Auvergne University, Clermont-Ferrand, France; 4Pulmonary Dpt, APHM, INSERM U1077, CNRS UMR 7733 Aix Marseille Université, Marseille, France; 5Pulmonary Dpt, Larrey University Hospital, Toulouse, France; 6Pulmonary Dpt, University Hospital, Saint-Etienne, France; 7Pulmonary Dpt, La Croix Rousse University Hospital, Lyon, France; 8Clinique des Maladies Respiratoires, Albert Calmette University Hospital, Lille, France; 9EFFI-STAT, Paris, France; 10Service de pneumologie, polyclinique Les Fleurs, Ollioules, France; 11Pulmonary Dpt, Bichat Hospital, AP-HP, Paris, France; 12Respiratory and Intensive Care Medicine Dpt, Cochin Hospital, AP-HP and Paris Descartes University (EA2511), Sorbonne Paris Cité, Paris, France *These authors contributed equally to this work Abstract: In patients with COPD, there is controversy regarding the association of blood eosinophil (Eos) levels with 1) exacerbation frequency and 2) the effect of inhaled corticosteroids for prevention of exacerbations. To determine whether Eos define subgroups of patients exhibiting attributes of COPD clinical phenotypes, we compared clinical features and mortality rates in COPD patients from the Initiatives BPCO French cohort categorized using different thresholds of blood Eos levels. The following data were collected at inclusion: medical and smoking history, occupational exposures, dyspnea, cough and sputum production, exacerbations in the previous year, history of allergy and asthma, nasal symptoms, body mass index, St George Respiratory Questionnaire (SGRQ) total score, post-bronchodilator spirometry, comorbidities, and medications. Three-year survival between groups was compared using Kaplan–Meier analysis. Three sets of analyses were performed to compare patients with ≥2% versus <2%, ≥3% versus <3%, and ≥4% versus <4% Eos. Eos was available in 458 patients (mean age: 62 years, 72% male, mean forced expiratory volume in 1 second: 51% pred), including 235 patients with Eos ≥2% (49%), 149 with Eos ≥3% (33%), and 90 with Eos ≥4% (20%). For all cutoffs, there was no difference between Eos+ and Eos- groups in univariate analyses except for diabetes and SGRQ score (more frequent and more impaired, respectively, in lower Eos categories). In particular, there was no difference in exacerbation rate, history of asthma, or three-year survival. In conclusion, regardless of the cutoff, Eos+ COPD patients exhibited no specific characteristic in terms of symptoms, lung function, exacerbation rate, and prognosis. These findings suggest that the association of higher Eos with exacerbations reported in previous studies could be population specific, which does not support generalizing the use of Eos as a biomarker for COPD phenotyping. Keywords: COPD, eosinophils, survival, exacerbations, quality of life