Causes & Development of Emphysema

Causes of Emphysema

It is known from scientific research that the normal lung has a remarkable balance between two classes of chemicals with opposing action. The lung also has a system of elastic fibers. The fibers allow the lungs to expand and contract. When the chemical balance is altered, the lungs lose the ability to protect themselves against the destruction of these elastic fibers. This is what happens in emphysema.

There are a number of reasons this chemical imbalance occurs. Smoking is responsible for 82% of chronic lung disease, including emphysema. Exposure to air pollution is one suspected cause. Irritating fumes and dusts on the job also are thought to be a factor.

A small number of people with emphysema have a rare inherited form of the disease called alpha I-antitrypsin (AAT) deficiency-related emphysema, or early onset emphysema. This form of disease is caused by an inherited lack of a protective protein called alpha I-antitrypsin (AAT).

How Does Emphysema Develop?

Emphysema begins with the destruction of air sacs (alveoli) in the lungs where oxygen from the air is exchanged for carbon dioxide in the blood. The walls of the air sacs are thin and fragile. Damage to the air sacs is irreversible and results in permanent "holes" in the tissues of the lower lungs. As air sacs are destroyed, the lungs are able to transfer less and less oxygen to the bloodstream, causing shortness of breath. The lungs also lose their elasticity. The patient experiences great difficulty exhaling.

Emphysema doesn't develop suddenly, it comes on very slowly. Years of exposure to the irritation of cigarette smoke usually precede the development of emphysema. A person may initially visit the doctor because they start to feel short of breath during activity or exercise. As the disease progresses, a short walk can be enough to bring on breathing difficulty. Some people may have chronic bronchitis before developing emphysema.