Paradigms in chronic obstructive pulmonary disease: phenotypes, immunobiology, and therapy with a focus on vascular disease

Abstract

Chronic obstructive pulmonary disease (COPD) is a complex and heterogeneous syndrome that represents a major global health burden. COPD phenotypes have recently emerged based on large cohort studies addressing the need to better characterize the syndrome. Though comprehensive phenotyping is still at an early stage, factors such as ethnicity and radiographic, serum, and exhaled breath biomarkers have shown promise. COPD is also an immunological disease where innate and adaptive immune responses to the environment and tobacco smoke are altered. The frequent overlap between COPD and other systemic diseases, such as cardiovascular disease, has influenced COPD therapy, and treatments for both conditions may lead to improved patient outcomes. Here, we discuss current paradigms that center on improving the definition of COPD, understanding the immunological overlap between COPD and vascular inflammation, and the treatment of COPD-with a focus on comorbid cardiovascular disease.

Keywords: Comorbidity; Phenotype; Pulmonary Disease, Chronic Obstructive.

Figure 1. Recommended therapy for stable COPD by GOLD category

Figure adapted from the recommendations of the Global Initiative for Chronic Obstructive Lung Disease (www.goldcopd.org, accessed Jan 2017). LABA, long-acting beta-2-agonist; LAMA, long-acting anti-muscarinic; ICS, inhaled corticosteroid. *First choice therapy includes short-acting beta2-agonists or short-acting anticholinergic medications as needed for all categories. First choice therapy also includes the first entry followed by a clinical evaluation. If the patient still has symptoms, then moving to the second entry is advised. **FEV1 impairment is FEV1≥50% predicted for GOLD Categories A and B, and FEV1<50% predicted for Categories C and D. †Symptoms based on the modified Medical Research Council (mMRC) scale: 0-shortness of breath (SOB) with strenuous exertion, 1-SOB with hurrying on level ground or inclines, 2-SOB with normal walking on level ground >100m, 3-SOB within 100m, and 4-SOB with daily activities; mMRC <2 = low symptoms and mMRC ≥2 = high symptoms.

Figure 2

Schematic showing the overlap between dysfunctional lung structural cells and inflammatory calls in COPD that may have a connection to cardiovascular disease.