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

Abstract

Purpose 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.

Comprehensive Nomograms Using Routine Biomarkers Beyond Eosinophil Levels: Enhancing Predictability of Corticosteroid Treatment Outcomes in AECOPD

“…Studies have indicated that patients with AECOPD with low blood eosinophils tend to be older, have more comorbidities and are more susceptible to severe bacterial infections, all of which contribute to poor prognoses. [36][37][38] Others regard eosinophilic AECOPD as an inflammatory phenotype, which demonstrates a favorable response to corticosteroid treatment. 10,13,14,[39][40][41] Our results align with this perspective.…”

The arrival ward requiring help by wheelchair or medical cart, arterial oxygenation index, age, albumin and neutrophil count score: Predicting in-hospital mortality in Chinese patients with acute exacerbations of chronic obstructive pulmonary disease

“…31 However, the in-hospital mortality rates were slightly lower in China, which ranged from 1.4% to 10.1%. 22,23,28,[32][33][34][35] Pu et al conducted a prospective cohort study with 12831 AECOPD inpatients, and found that the in-hospital mortality rate was 1.4%. 32 Peng et al conducted a retrospective study with 6668 patients hospitalized for AECOPD, and reported that the in-hospital mortality was 1.9%.…”

“…22,23,28,[32][33][34][35] Pu et al conducted a prospective cohort study with 12831 AECOPD inpatients, and found that the in-hospital mortality rate was 1.4%. 32 Peng et al conducted a retrospective study with 6668 patients hospitalized for AECOPD, and reported that the in-hospital mortality was 1.9%. 33 Five other studies with relatively smaller samples reported inhospital mortality rates of 6.0%, 22 7.0%, 34 7.2%, 35 9.7%, 28 and 10.1%, 23 respectively.…”

Eosinophils and chronic obstructive pulmonary diseases (COPD) in hospitalized COVID-19 patients

“…In recent years, eosinophil levels in peripheral blood have become one of the emerging biomarkers in patients with COPD because there is evidence that eosinophils participate in the pathophysiological mechanisms of the disease, and their measurement is possible in most laboratories [ 11 ]. However, the effect of eosinophils in stable COPD and COPD exacerbations may differ [ 12 ].…”