A person with chronic obstructive pulmonary disease has damage to the air passageways in the lungs, usually caused by smoking. Additional causes include occupational exposure to dust, fumes and smoke.

The damage from COPD causes a persistent cough, wheezing and difficulty breathing.

COPD results in either:

• Chronic bronchitis:
• Damage to the bronchial tubes
• Emphysema:
• Damage to the tiny tubes called bronchioles and the air sacs in the lungs. This leads to air trapping due to the formation of air pockets in the lung tissue.