Objective:To explore the risk factors of acute exacerbation (AE) of chronic obstructive pulmonary disease (COPD) and whether Eosinophil (EOS) in peripheral blood can guide the treatment of inhaled corticosteroids (ICS).Methods:This study was a single center, Prospective cohort study. The subjects of this study were from stable COPD patients who were treated in the Department of Respiratory Medicine of the Xiangya Second Hospital of Central South University from January 2020 to December 2021. Patient general information, past year AE status, exposure risk factors, modified version of the British Medical Research Council Respiratory Difficulty Questionnaire (mMRC) score, Chronic Obstructive Pulmonary Disease Assessment Questionnaire (CAT) score, ICS usage, lung function, blood routine, etc. were collected. We followed up the patient for one year. During the follow-up period, the clinical characteristics of patients with and without AE were compared to analyze the correlation between blood EOS and ICS use.Results:The median blood EOS of 617 stable COPD patients was 0.13×10 9/L, 289 patients (46.8%) with chronic obstructive pulmonary disease had a history of AE, and 207 patients (33.5%) experienced AE during 1-year follow-up. The results of univariate analysis showed that the future occurrence of AE in COPD was correlated with body mass index (BMI), AE history, Global Initiative for Chronic Obstructive Lung Disease (GOLD) grading, GOLD grouping, mMRC score, and CAT score (all P<0.05). The results of logistic multiple factor regression analysis showed that patients with BMI<24 kg/m 2, AE in the past year, severe AE in the past year, smoking history and other exposure factors, GOLD level 2 or above, GOLD C and D groups, and mMRC score≥ 2 had a higher risk of future AE (all P<0.05). There was no statistically significant difference in the incidence of AE between patients with COPD with different levels of EOS and those without ICS during a 1-year follow-up period (all P>0.05). Conclusions:The past 1-year AE history, BMI, exposure risk factors, degree of airflow restriction, and respiratory symptoms of patients with chronic obstructive pulmonary disease can predict future AE risk. There is no significant difference in future AE risk among patients with different levels of EOS, and EOS cannot guide ICS treatment to reduce AE risk.

Objective:To understand the use of inhaled corticosteroids (ICS) in patients with chronic obstructive pulmonary disease (COPD) in the real world and analyze its compliance with the guidelines.Methods:This study is a multicenter, cross-sectional study. 1 051 COPD patients who were treated in the Second Xiangya Hospital of Central South University, the First Affiliated Hospital of Shaoyang College and Zhuzhou Central Hospital from January 2020 to March 2022 were collected. The general information, drug use, types of exposure risk factors, acute exacerbation (AE) in the past year, the scores of the modified British Medical Research Council Dyspnea Questionnaire (mMRC), COPD Assessment Test (CAT), pulmonary function, blood routine of patients were collected. The status of ICS use in COPD patients, the clinical characteristics and guideline compliance of non-ICS users and ICS users were analyzed.Results:Among 1 051 patients with COPD, ICS was used in 490 cases (46.6%) and was not used in 561 cases (53.4%). ICS use was associated with relapse, frequent AE, severe AE, Global Initiative for Chronic Obstructive Pulmonary Disease (GOLD) grade 2 or above, GOLD D group, mMRC score, bronchial asthma, and blood eosinophils (EOS) (all P<0.05). Among 1 051 patients, 583(55.5%) were newly treated, 222(38.1%) were newly treated with ICS, and 361(61.9%) were not treated with ICS. ICS use in newly treated patients was associated with frequent AE, severe AE in the past year, GOLD grade 2 to 3, GOLD B and D group, mMRC score, bronchial asthma, and blood EOS (all P<0.05). Conclusions:Nearly half of patients with COPD are treated with ICS, and patients with ICS use had a higher risk of AE, more severe symptoms, higher blood EOS, and higher rates of asthma. However, there still exists the phenomenon of overuse of ICS.