Chronic Obstructive Pulmonary Disease

Abstract

The past decade has witnessed great progress in chronic obstructive pulmonary disease (COPD) research. New drugs have been developed and tested, indications for lung volume reduction surgery (LVRS) have been determined, and a growing base of scientific evidence now documents the efficacy of various therapies for symptoms and exacerbations. This advance in knowledge shatters the old conception of COPD as a hopelessly untreatable condition (1–4). It is clear that many patients with COPD can benefit from aggressive management, with a decrease in the frequency of hospitalizations and improvements in quality of life and survival. In addition, basic and clinical scientists have now identified cells, mechanisms, and molecules that appear to play key roles in disease pathogenesis. Additional novel treatments are on the horizon. The good news about COPD is getting out as many organizations are working effectively to increase awareness of the disease (5). Despite advances in care, the COPD epidemic persists, causing more than 120,000 deaths per year in the United States alone. COPD's position as the fourth leading cause of death in the United States is ominous and the probability of the number of cases rising even further is disturbing. Population-based surveys show that as many as 24 million people in the United States have airflow limitation consistent with COPD and that half or more of these cases have not yet been diagnosed (6). Despite the availability of effective treatments for COPD, no existing therapy halts or reverses the progressive and accelerated decline in lung function that is characteristic of this condition. We are far from having a cure for COPD, and in fact, the most basic questions about this disease remain unanswered: Why do only a minority of smokers develop clinically significant COPD? Why is there great heterogeneity in the presentation of COPD? Which pathogenetic pathways are critical, and how can they be modulated therapeutically? Why does the disease continue to progress even after smoking cessation? How can the lung injury that characterizes COPD be reversed? Better means of preventing and treating COPD are urgently needed, but it is not entirely clear what studies should be done. The strategic decisions in COPD research—which investigative approaches to use, which hypotheses to test, which pathways to explore in detail, which basic findings to translate into human studies, and which therapeutic targets to test—are perhaps more difficult to make now than ever before. As opportunities for investigation in COPD have expanded, the pulmonary community's task of choosing the most effective directions and approaches for COPD research has become even more complex, and wise choices are critical to secure future success. In this essay, we encourage the pulmonary medical community to think about needs, opportunities, and the most productive approaches for research in COPD. We summarize new research directions and findings, how the disease itself is evolving, what research activities are currently underway, and how the infrastructure and organization of the research enterprise in the United States is adapting to new biological and technological challenges and advances that offer unprecedented opportunities for COPD research. We close with a call to action that presses the pulmonary community to widen its horizons and build interdisciplinary teams to better confront the problems of COPD.