Blood Eosinophils and Clinical Outcomes in Inpatients with Acute Exacerbation of Chronic Obstructive Pulmonary Disease: A Prospective Cohort Study

Abstract

Jiaqi Pu,1,* Qun Yi,1,2,* Yuanming Luo,3 Hailong Wei,4 Huiqing Ge,5 Huiguo Liu,6 Xianhua Li,7 Jianchu Zhang,8 Pinhua Pan,9 Hui Zhou,10 Chen Zhou,11 Mengqiu Yi,12 Lina Cheng,12 Liang Liu,10 Jiarui Zhang,1 Lige Peng,1 Adila Aili,1 Yu Liu,1 Haixia Zhou1 On behalf of the MAGNET AECOPD Registry Investigators1Department of Respiratory and Critical Care Medicine, West China Hospital, Sichuan University, Chengdu, People’s Republic of China; 2Sichuan Cancer Hospital and Institution, Sichuan Cancer Center, Cancer Hospital Affiliate to School of Medicine, UESTC, Chengdu, People’s Republic of China; 3State Key Laboratory of Respiratory Disease, Guangzhou Medical University, Guangzhou, People’s Republic of China; 4Department of Respiratory and Critical Care Medicine, People’s Hospital of Leshan, Leshan, People’s Republic of China; 5Department of Respiratory and Critical Care Medicine, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, People’s Republic of China; 6Department of Respiratory and Critical Care Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People’s Republic of China; 7Department of Respiratory and Critical Care Medicine, the First People’s Hospital of Neijiang City, Neijiang, People’s Republic of China; 8Department of Respiratory and Critical Care Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People’s Republic of China; 9Department of Respiratory and Critical Care Medicine, Xiangya Hospital, Central South University, Changsha, People’s Republic of China; 10Department of Respiratory and Critical Care Medicine, The Affiliated Hospital of Chengdu University, Chengdu, People’s Republic of China; 11West China School of Medicine, West China Hospital, Sichuan University, Chengdu, People’s Republic of China; 12Department of Emergency, First People’s Hospital of Jiujiang, Jiu Jiang, People’s Republic of China*These authors contributed equally to this workCorrespondence: Haixia Zhou, Department of Respiratory and Critical Care Medicine, West China Hospital, Sichuan University, Guo-Xue-Xiang 37#, Wuhou District, Chengdu, Sichuan Province, 610041, People’s Republic of China, Tel/Fax [phone], Email [email protected]: The prognostic value of blood eosinophils in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) remains controversial. This study aimed to evaluate whether blood eosinophils could predict in-hospital mortality and other adverse outcomes in inpatients with AECOPD.Methods: The patients hospitalized for AECOPD were prospectively enrolled from ten medical centers in China. Peripheral blood eosinophils were detected on admission, and the patients were divided into eosinophilic and non-eosinophilic groups with 2% as the cutoff value. The primary outcome was all-cause in-hospital mortality.Results: A total of 12,831 AECOPD inpatients were included. The non-eosinophilic group was associated with higher in-hospital mortality than the eosinophilic group in the overall cohort (1.8% vs 0.7%, P < 0.001), the subgroup with pneumonia (2.3% vs 0.9%, P = 0.016) or with respiratory failure (2.2% vs 1.1%, P = 0.009), but not in the subgroup with ICU admission (8.4% vs 4.5%, P = 0.080). The lack of association still remained even after adjusting for confounding factors in subgroup with ICU admission. Being consistent across the overall cohort and all subgroups, non-eosinophilic AECOPD was also related to greater rates of invasive mechanical ventilation (4.3% vs 1.3%, P < 0.001), ICU admission (8.9% vs 4.2%, P < 0.001), and, unexpectedly, systemic corticosteroid usage (45.3% vs 31.7%, P < 0.001). Non-eosinophilic AECOPD was associated with longer hospital stay in the overall cohort and subgroup with respiratory failure (both P < 0.001) but not in those with pneumonia (P = 0.341) or ICU admission (P = 0.934).Conclusion: Peripheral blood eosinophils on admission may be used as an effective biomarker to predict in-hospital mortality in most AECOPD inpatients, but not in patients admitted into ICU. Eosinophil-guided corticosteroid therapy should be further studied to better guide the administration of corticosteroids in clinical practice.Keywords: acute exacerbation of chronic obstructive pulmonary disease, peripheral blood eosinophils, inpatients, in-hospital mortality, clinical outcomes

Keywords

• acute exacerbation of chronic obstructive pulmonary disease
• peripheral blood eosinophils
• inpatients
• in-hospital mortality
• clinical outcomes