Chronic Obstructive Pulmonary Disease
Chronic obstructive pulmonary disease (COPD) is the name for a group of lung conditions that cause breathing difficulties. It includes emphysema (damage to the air sacs in the lungs) and chronic bronchitis (long-term inflammation of the airways). COPD is a common condition that mainly affects middle-aged or older adults who smoke. Many people do not realise they have it. The breathing problems tend to get gradually worse over time and can limit your normal activities, although treatment can help keep the condition under control.
Source: NHS