Chronic obstructive pulmonary disease (COPD) is a general term which covers many previously used clinical labels which are now recognised as being different aspects of the same problem.

Diagnostic labels encompassed by COPD include:

• chronic bronchitis
• emphysema
• chronic obstructive airways disease
• chronic airflow limitation
• some cases of chronic asthma

COPD is a chronic, slowly progressive disorder characterised by airways obstruction (FEV1 < 80% predicted and FEV1/FVC ratio < 70%) which does not change markedly over several months. The impairment of lung function is largely fixed but is partially reversible by bronchodilator or other therapy.

Environmental pollution and smoking contribute to the increasing incidence of COPD.

COPD is an important cause of activity limitation in the population.