5.8.1. Introduction

The term Chronic Obstructive Pulmonary Disease (COPD) refers to pathologies characterized by airflow limitation (AL) such as chronic bronchitis and emphysema. COPD is a common, costly and preventable disease that has substantial implications for the health of the European population. COPD is a treatable disease, when AL is progressive and not fully reversible. However, COPD is often underestimated and under-treated.

Approximately 200 000-300 000 people die every year in Europe because of COPD. It represents the fifth leading cause of mortality in the developed world (Lopez et al, 2001) and the third cause of death in the UE-25 (Niederlander et al, 2006). COPD is the main reason for mortality associated with respiratory diseases, accounting for 3.8% of total deaths and is also estimated to be the seventh cause of loss of disability adjusted life years (Mannino and Buist, 2007). Moreover, significant augmentations in COPD prevalence and mortality are envisaged in the future; the most well known projection comes from the authoritative and widely quoted Global Burden of Disease study, which envisaged that COPD would rise to the third leading cause of death worldwide in 2020 (Murray and Lopez, 1997).

The main elements of COPD are chronic bronchitis and emphysema: (Siafakas, 2006). COPD has significant extra-pulmonary effects that may contribute to the severity in individual patients. Its pulmonary element is characterized by AL that is not fully reversible. The airflow limitation is usually progressive and associated to an abnormal inflammatory response of the lung to noxious particles or gases (GOLD, 2006).

Exposure to noxious agents (e.g. tobacco active and passive tobacco smoking, occupational factors and air pollution) causes a rapid deterioration in the lung function, increasing the risk for exacerbations. These exacerbations lead to a progressive worsening until the end stage of the disease, characterized by severe airflow limitation, chronic respiratory failure, different co-morbidities and severe systemic complications.

Major efforts in the field of prevention are necessary to avoid an important augmentation in end-stage patients, needing long term oxygen therapy and assisted ventilation, which would prolong their life but cause great suffering and costs.