Chronic obstructive pulmonary disease (COPD) is characterised by persistent airflow limitation that is usually progressive and associated with a chronic inflammatory response in the airways and lungs to noxious particles or gases. The persistent airflow limitation results from a combination of diffuse small airway disease and destruction of the lung parenchyma (emphysema).

COPD is a syndrome with many phenotypes. They have been poorly defined and knowledge of their specific aetiology, pathogenesis, management and meaningful outcomes is limited. Chronic bronchitis (defined as cough and phlegm for at least 3 months per year in 2 consecutive years) may precede or coincide with airway narrowing but may also be seen in patients without COPD.

The diagnostic criterion for COPD is based on spirometry confirming a reduction in the ratio of forced expiratory volume in 1 second (FEV1) to forced vital capacity (FVC). Severity is graded as shown in table 1. There is, however, ongoing discussion about the most appropriate spirometric criterion to use, either reduction of the ratio of FEV1/FVC below a fixed value (usually 70%) or below the lower limit of normal FEV1/FVC for the age and sex of the subject. Since even in healthy individuals the FEV1/FVC ratio declines with age, use of the former criterion rather than the latter can result in overdiagnosis of COPD in the elderly and underdiagnosis in younger subjects.

ATS/ERS criteria  
Mild FEV1/VC <5th percentile of predicted and FEV1 ≥70% pred
Moderate FEV1/VC <5th percentile of predicted and FEV1 60–69% pred
Moderately severe FEV1/VC <5th percentile of predicted and FEV1 50–59% pred
Severe FEV1/VC <5th percentile of predicted and FEV1 35–49% pred
Very severe FEV1/VC <5th percentile of predicted and FEV1 <35% pred
GOLD criteria  
Mild (stage I) FEV1/FVC <0.70 and FEV1 >80% pred
Moderate (stage II) FEV1/FVC <0.70 and 50%≤FEV1 <80% pred
Severe (stage III) FEV1/FVC <0.70 and 30%≤FEV1 <50% pred
Very severe (stage IV) FEV1/FVC <0.70 and FEV1 <30% pred
FEV1/FVC <0.70 and FEV1 <50% pred and chronic respiratory failure
Table 1 – Classification and severity staging of airflow obstruction according to the American Thoracic Society (ATS)/European Respiratory Society (ERS) and the Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria. FEV1: forced expiratory volume in 1 second; VC: vital capacity; % pred: % of predicted value; FVC: forced vital capacity. Reproduced from BAakke et al., 2011.

COPD is a major burden to many individuals, societies and healthcare budgets throughout the world. Its impact is expected to rise both in industrialised and developing countries in the decades to come, partly due to continued exposure to risk factors for COPD and partly due to an ageing world population. People who live longer are more likely to experience the consequences of long-term exposure to COPD risk factors.

The aim of this chapter is to describe the epidemiology, risk factors, clinical picture, management, and future trends of COPD in Europe.

See the entire Obstructive pulmonary disease Chapter