Neutrophil-to-Lymphocyte Ratio Predicts Clinical Outcome of Severe Acute Exacerbation of COPD in Frequent Exacerbators

Fang-Ying Lu; Rong Chen; Ning Li; Xian-Wen Sun; Min Zhou; Qing-Yun Li; Yi Guo

doi:10.2147/COPD.S290422

Neutrophil-to-Lymphocyte Ratio Predicts Clinical Outcome of Severe Acute Exacerbation of COPD in Frequent Exacerbators

Int J Chron Obstruct Pulmon Dis. 2021 Feb 17:16:341-349. doi: 10.2147/COPD.S290422. eCollection 2021.

Authors

Fang-Ying Lu^#^{1

2}, Rong Chen^#^{1

2}, Ning Li^{1

2}, Xian-Wen Sun^{1

2}, Min Zhou^{1

2}, Qing-Yun Li^{1

2}, Yi Guo^{1

2}

Affiliations

¹ Department of Respiratory and Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China.
² Institute of Respiratory Diseases, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China.

^# Contributed equally.

Abstract

Purpose: Frequent exacerbators are a specific phenotype of chronic obstructive pulmonary disease (COPD), whose clinical characteristics and prognostic biomarkers during severe acute exacerbation (AECOPD) have not yet been fully elucidated. The aim of this study was to investigate the clinical features of severe AECOPD in frequent exacerbators and explore the predictive value of the neutrophil-to-lymphocyte ratio (NLR) for outcome in this phenotype during severe exacerbation.

Patients and methods: A total of 604 patients with severe AECOPD were retrospectively included in the study. Subjects were defined as frequent exacerbators if they experienced two or more exacerbations in the past year. Clinical characteristics and worse outcome (ICU admission, or invasive ventilation, or in-hospital mortality) during severe AECOPD were compared between frequent exacerbators and non-frequent ones. Furthermore, the relationship between NLR and worse outcome in frequent exacerbators was analyzed using logistic regression and receiver operating characteristic (ROC).

Results: Among 604 patients with severe AECOPD, 282 (46.69%) were frequent exacerbators and 322 (53.31%) were non-frequent exacerbators. Compared with the non-frequent ones, frequent exacerbators presented higher levels of NLR (5.93 [IQR, 3.40-9.28] vs 4.41 [IQR, 2.74-6.80]; p<0.001), and more worse outcome incidence (58 [20.57%] vs 38 [11.80%]; p=0.003). Moreover, among the frequent exacerbators, NLR levels in the patients with worse outcome were much higher than in those without worse outcome (11.09 [IQR, 7.74-16.49] vs 5.28 [IQR, 2.93-7.93]; p<0.001). Increased NLR was significantly associated with a higher risk of worse outcome in frequent exacerbators (OR, 1.43; 95% CI, 1.28-1.64; p<0.001). Furthermore, ROC analysis revealed that a cut-off value of 10.23, NLR could predict worse outcome of severe AECOPD in frequent exacerbators (sensitivity 62.1%, specificity 92.0%, AUC 0.833).

Conclusion: Frequent exacerbators exhibited an increased level of NLR and a higher proportion of worse outcome during severe AECOPD. NLR is expected to be a promising predictive biomarker for the prognosis of severe AECOPD in frequent exacerbators.

Keywords: COPD; NLR; frequent exacerbator; severe exacerbation; worse outcome.

MeSH terms

Disease Progression
Humans
Lymphocytes
Neutrophils*
Prognosis
Pulmonary Disease, Chronic Obstructive* / diagnosis
Pulmonary Disease, Chronic Obstructive* / therapy
Retrospective Studies

Grants and funding

This work was supported by National Key R&D Program of China [granted number 2017YFC1309701, 2017YFC1309700 and 2018YFC1311900]; National Natural Science Foundation of China [granted number 81570029]; Grant of Beijing Bethune Charitable Foundation [granted number BJ-RW2020003J] and Shanghai Key Discipline for Respiratory Diseases [granted number 2017ZZ02014].