Asthma-COPD overlap as a multidimensional disease space: heterogeneity, phenotypes, endotypes, and treatable traits.

Both asthma and chronic obstructive pulmonary disease (COPD) are heterogeneous diseases characterised by airway obstruction. In recent years, they have received increasing attention due to the annual increase in morbidity and mortality. Asthma and COPD have different inflammatory patterns and underlying mechanisms. Asthma-COPD overlap (ACO) is a characteristic of both asthma and COPD. ACO is not simply a superposition of asthma and COPD but a heterogeneous multidimensional clinical construct. This not only increases the complexity of diagnosis, but also poses higher requirements for the selection of treatment strategies. This review presents an in-depth exploration of ACO from a multidimensional perspective, based on its heterogeneity, phenotypes, endotypes, and treatable characteristics. This study aimed to better address the diversity of the disease, explore more effective treatment approaches, reduce the disease burden, and improve patient prognosis.