Increased Serum Soluble Interleukin-2 Receptor Associated with Severity of Acute Exacerbation of Chronic Obstructive Pulmonary Disease

Abstract

Background

This study aimed to reveal the correlation between serum soluble interleukin-2 receptor (sIL-2R) and prognosis in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD).

Methods

A total of 315 patients diagnosed with AECOPD between December 2017 and June 2020 were enrolled. The patients were divided into the good and adverse groups based on the outcomes. An adverse outcome in COPD exacerbation was defined by the presence of at least one of the following: (1) death from a respiratory cause during hospitalisation or within 1 month of follow-up; (2) intensive care unit admission; (3) invasive or non-invasive mechanical ventilation; and (4) COPD-related emergency visit or readmission within 1 month of follow-up. A good outcome was considered as the absence of all the aforementioned issues. The patients underwent lung function (spirometry) assessment, and clinical and inflammatory profiles were collected. Univariate and multivariate analyses were performed to identify the correlation between serum sIL-2R concentration and other variables related to adverse outcomes of AECOPD. The receiver operating characteristic curve was used to show the predictive ability of sIL-2R for adverse outcomes of AECOPD.

Results

We enrolled 315 patients, of whom 161 and 154 had good and adverse outcomes, respectively. We demonstrated that patients with adverse outcomes of AECOPD had a higher concentration of serum sIL-2R than patients with good outcomes (p < 0.001). The increased serum sIL-2R was positively associated with mMRC scores (p < 0.001), GLOD grades (p < 0.001), frequent exacerbation (p < 0.001), and smoking (p < 0.001) in patients with AECOPD and negatively correlated with pulmonary function (p < 0.001). An elevated sIL-2R level was a predictor for the risk of adverse outcomes in AECOPD with a cut-off value of 860 U/mL.

Conclusion

Increased serum sIL-2R concentration correlated with the risk of the adverse outcomes in AECOPD, indicating that it can be a predictive factor contributing to the diagnosis and assessment of adverse outcomes in patients with AECOPD.

Keywords:

• chronic obstructive pulmonary disease
• acute exacerbation
• soluble interleukin-2 receptor
• predictive factor

Abbreviations

COPD, Chronic obstructive pulmonary disease; GOLD, Global Initiative for Chronic Obstructive Lung Disease; AECOPD, Acute exacerbation of COPD; %pred, Percent of predicted; FEV₁/FVC, Forced expiratory volume/forced vital capacity; SI, Smoking index; mMRC, Modified British Medical Research Council; PaCO₂, Partial arterial carbon dioxide pressure; PaO₂/FiO₂, Ratio of partial arterial oxygen pressure to the fraction of inspired oxygen; WBC, Whole blood leukocyte counts; CRP, C-reactive protein; ESR, Erythrocyte sedimentation rate; PCT, procalcitonin; IL-6, Interleukin-6; IL-8, Interleukin-8; IL-10, Interleukin-10; TNF-α, Tumour necrosis factor-α; sIL-2R, Soluble interleukin-2 receptor; OR, Odds ratio; CI, Confidence interval; ROC, Receiver operating characteristic; AUC, Area under the curve.

Data Sharing Statement

The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.

Ethics Approval and Consent to Participate

The study protocol was approved by the Human Research Ethics Committee of the Xinhua Hospital affiliated to Shanghai Jiaotong University Medical College (XHEC-C-2017-085). Written informed consent was obtained from each participant. This study was conducted in accordance with the Declaration of Helsinki.

Acknowledgments

The authors thank all miner workers who participated in this study.

Author Contributions

All authors contributed to data analysis, drafting or revising the article, gave final approval of the version to be published, agreed to the submitted journal, and agree to be accountable for all aspects of the work.

Disclosure

The authors declare that they have no competing interests in this work.

Additional information

Funding

This work was supported by Hospital Foundation of Xinhua Hospital, to Yue Zhang, Shanghai Science and Technology Commission Grant of China, No:17511108502, 2017.7-2019.6.