Concept of Treatable Traits and ACO: Can Treatable Traits Approach Be Applied into Practice?

Asthma and chronic obstructive pulmonary disease (COPD) are extremely heterogeneous diseases with respect to symptoms, severity, and response to treatment. The term “asthma–COPD overlap” (ACO) is used to describe a condition that combines the characteristics of both diseases, but it is not a single disease and is equally as diverse. Until the early twenty-first century, the treatment for chronic airway diseases such as asthma and COPD was largely based on an approach termed as one-size-fits-all medicine. However, this approach has been recognized to have limitations in providing appropriate treatment for a variety of conditions that vary from patient to patient. Recently, the importance of understanding the treatable trait has been emphasized for the provision of precision and personalized medicine for treating chronic inflammatory lung disease. The newly proposed concept is known as treatable traits, which implies the traits and characteristics of patients that must be considered to provide optimal treatment. It is a new approach that seeks treatment options in a multidimensional manner based on the clinical traits and characteristics of individual patients without being limited by the conventional diagnosis. This chapter summarizes previous reports on treatable traits in patients with ACO and outlines future perspectives.