Asthma and COPD are prevalent chronic diseases characterised by presence of respiratory symptoms and airflow limitation caused by ongoing inflammatory process in the airways [1, 2]. While the clinical features are reversible or variable over time in asthma [1], they are more persistent and usually progressive over time in COPD [2]. The connection between these two common disorders has been debated thoroughly for many decades with proponents for both "splitting" or "lumping" them into either two distinct or one common entity [3–6]. The clinical heterogeneity of both conditions has also been recognised for a long time, and the fact that some patients show characteristics of both diseases simultaneously resulted in the official introduction of the asthma–COPD overlap label by the Global Initiative for Chronic Obstructive Lung Disease (GOLD) and Global Initiative for Asthma committees in 2014 [7].

哮喘和 COPD 是一种常见的慢性疾病，其特征是存在呼吸道症状和由气道持续炎症过程引起的气流受限 [1, 2]。虽然哮喘的临床特征随着时间的推移是可逆的或可变的 [1]，但在 COPD [2] 中它们更持久并且通常随着时间的推移而进展。几十年来，这两种常见疾病之间的联系一直被彻底辩论，支持者将它们“拆分”或“集中”成两个不同的实体或一个共同的实体 [3-6]。长期以来，这两种情况的临床异质性也得到了认可，