• Chronic obstructive pulmonary disease (COPD) is a chronic respiratory disorder characterised by chronic airflow limitation, shortness of breath (dyspnea), cough, wheezing and increased sputum production, which can restrict a patient’s ability to perform normal daily activities.
• The term COPD encompasses both chronic bronchitis and emphysema. 

What does COPD mean for the patient?

• The chronic airflow limitation associated with COPD leads to air being trapped in the lungs (hyperinflation) which in turn causes the dypsnea or breathlessness. In the early stages of the disease this occurs mostly during physical activity, as the disease progresses the breathlessness becomes present even at rest. Along with the other common symptoms this can restrict a patient's ability to perform normal daily activities and severely impact quality of life.

What causes COPD?

• Cigarette smoking is the predominant risk factor for COPD, accounting for 80%-90% of the risk for developing the disease, yet only about 15% of all smokers develop COPD severe enough to cause symptoms. 
• However, smoking is not the only risk. Populations exposed to indoor pollution resulting from the use of wood and coal-burning stoves and heaters have a greatly increased risk. Occupational exposure to a variety of airborne dusts also increases the risk of COPD, as does air pollution. 

How is COPD different from asthma?

The natural histories of COPD and asthma are distinctly different:

• Dyspnea, or shortness of breath, that is progressive and experienced every day is more common in COPD than in asthma.
• COPD symptoms are progressive and typically worsen with age, whereas asthma symptoms are usually more episodic and stable over time.