Chronic Obstructive Pulmonary Disease (COPD)
COPD is a major non-communicable disease, currently the third leading cause of death in the world, accounting for 5.3% of all deaths, with no treatment available to date. In 2015, 3.2 million people died of COPD worldwide, which represents an increase of 11.6 percent compared with 1990. The annual cost for COPD alone is almost €50 billion, which represents the largest economic burden on health services in terms of respiratory diseases and loss of production in the EU. COPD is characterized by persistent and usually progressive airflow limitation resulting from a combination of a diffuse disease of small airways and the destruction of the pulmonary parenchyma (emphysema). However, COPD patients present multiple variations of their phenotype that may imply different origins and underlying pathophysiological mechanisms, and which increases the complexity of medical treatment.
The main risk factor for developing COPD is smoking; about 40-50% of lifetime smokers will develop COPD. However, at equivalent tobacco consumption, not all smokers develop clinically significant COPD, suggesting that other risk factors should be taken into account, such as occupational exposures, air pollution (indoor/outdoor), as well as genetic factors that may modify the individual risk of developing COPD.
Overall, COPD can no longer be considered as a single entity caused by susceptibility to cigarette smoke, but rather as a syndrome, encompassing several phenotypes. The genetic and environmental determinants identified for a COPD phenotype may not be common to all COPD phenotypes.