Chronic Obstructive Pulmonary Disease and Irreversible Airflow Obstruction

Abstract

Patients with fixed airflow obstruction, whether from asthma or chronic obstructive pulmonary disease (COPD), or an overlap phenotype, represent an especially difficult group of patients to both categorize and manage. Many of the current research activities in both asthma and COPD are designed to subclassify patients with asthma and COPD into different endotypes and phenotypes, with the hope that the results will have implications for both the natural history of disease and the response to different therapies. Data outlined in this review, particularly the genetic findings, help strengthen the “Dutch hypothesis” Orie put forth more than 50 years ago about the commonalities of obstructive airways diseases operating under a variety of environmental influences. The identification of targets distinct from inflammation in both asthma and COPD, through different mechanisms—atopy, important in asthma, and smoking, important COPD–could lead to novel treatments for both of these diseases with fixed airflow obstruction. In the meantime, the use of bronchodilators, antiinflammatory agents, and environmental control and intervention, including smoking cessation, weight loss and control, and exercise and pulmonary rehabilitation, remain the foundation of the therapeutic approach for these diseases, regardless of their origin.