Chronic Obstructive Pulmonary Disease and Emphysema

Chronic obstructive pulmonary disease (COPD) comprises a spectrum of highly variable respiratory disorders that include emphysema, chronic bronchitis, and small airways disease. The diagnosis of COPD is commonly associated with active or remote tobacco smoking; however, other causal factors, including chronic exposure to environmental pollutants, inhalation of nano-particulate matter, and recurrent infections, have also been identified. In this chapter, we provide an overview of characteristics associated with different COPD clinical phenotypes: obstructive airway disease, emphysematous, and obstructive, as well as asthma/COPD overlap. In each case, a discussion of the disease’s immunopathophysiology associated with a distinct or an overlapping clinical phenotype (e.g., endotypes) will be discussed. Diagnosis of emphysema in former or active smokers is of paramount importance because this specific endotype is associated with the presence of antigen-specific autoinflammatory cells. Provided are a state-of-the-art description of COPD endotypes and our current knowledge based on the immunopathogenesis of COPD to direct new therapies. Recent clinical trials using pharmacological interventions to mitigate disease progression will be highlighted as future treatments to temper the progressive inflammation that is highly characteristic of emphysema.