Emerging Role of Soluble Suppression of Tumorigenicity 2 as Biomarker for Acute Exacerbations in COPD Patients

Abstract Early and precise assessment of acute exacerbations of chronic obstructive pulmonary disease (AECOPD) is crucial for the clinical management of COPD patients. Soluble suppression of tumorigenicity 2 (sST2) has been observed to increase in inflammatory lung diseases. This study aimed to investigate whether sST2 could serve as a biomarker for AECOPD and predict disease severity. We investigated 55 AECOPD patients, 30 stable COPD patients, and 33 healthy controls. COPD patients had higher sST2 levels than healthy controls. Additionally, sST2 levels showed significant differences among AECOPD patients with different GOLD classes and levels of deterioration, and were significantly correlated with inflammatory markers and pulmonary function tests in these patients. Multivariate logistic regression analyses showed that sST2 was an independent risk factor for AECOPD patients. AECOPD patients with bacterial infection also had significantly higher sST2 levels than those with non-bacterial infection. The performance of sST2 in differentiating AECOPD patients from those with a 4-week stable condition, as well as AECOPD patients with bacterial infection, surpasses that of CRP and PCT. In conclusion, our result suggests that sST2 may serve as a biomarker to predict AECOPD and disease severity, and assist in differentiating bacterial exacerbations in COPD patients.