Airway Disorders as Predictive Factors of Exacerbations in Asthma and COPD

Abstract

Asthma and chronic obstructive pulmonary disease (COPD) are heterogenous diseases in the respiratory system. Since wheezing, reduced FEV1, eosinophilic airway inflammation, and airway hyperresponsiveness are observed in some patients with COPD similar to asthma, differential diagnosis is sometimes difficult in subset of these diseases. To advance the management and treatment of asthma and COPD, it is necessary to accurately classify patients with these two diseases according to distinct clinical phenotypes based on clinically meaningful outcomes such as symptoms, exacerbations, response to therapy, and prognosis. However, since several phenotypes are present in individual patients, a search for treatable traits needs to establish precision medicine for asthma and COPD. Since these diseases worsen with each repeated exacerbation, the establishment of treatment to avoid exacerbations is the most important goal of the long-term management of these diseases. Airway physiological and pathological disorders, such as reversibility in FEV1, airway hyperresponsiveness, airway eosinophilic inflammation, and upper respiratory infection, are probably considered as major predictors of exacerbations. This chapter states clinical phenotypes related to acute exacerbation to establish treatable traits for asthma and COPD.