About 300 million tiny air sacs, with their thin, elastic membranes, ensure gas exchange: the intake of oxygen from the air we breathe and the release of carbon dioxide from the body. Without these alveoli, we would gasp for air like a fish on land. Chronic lung disease can cause these air chambers to expand, resulting in damage to the fine membranes. The result is increasing, irreversible shortness of breath.
How does this disease develop?
In Germany, an estimated 400,000 people currently suffer from emphysema – with a rising trend. In most cases, those affected are older than 50 years.
- In almost all cases, lung hyperinflation is preceded by years of smoking and/or chronic bronchitis. The ongoing irritation of the mucous membrane in the airways causes an inflammatory response. As a result, thick mucus is formed and the tissue changes. The result is chronic obstructive pulmonary disease (COPD), in which the bronchi collapse. Air cannot be exhaled properly and remains trapped in the air spaces. If the inflammatory processes also spread to the walls between the alveoli (alveolar septa), they tear. This turns several small bubbles into a few large ones – emphysema. There is less and less space available for gas exchange, so that the affected person must do more breathing work for the same amount of oxygen or can no longer meet the increased demand for oxygen during physical exertion.
- In about 2% of emphysema patients, there is an underlying inherited enzyme defect, alpha-1 antitrypsin deficiency. This protein is found in the blood and protects, among other things, the alveoli from aggressive substances. In patients with the disease, its concentration is severely reduced. This leads to inflammation and the processes described above set in.
- Other causes include age-related loss of elasticity (senile emphysema), scarring changes in other lung diseases (cicatricial emphysema) and over-expansion of the lungs, for example, when a part has been removed and the remaining lung fills the remaining space (over-expansion emphysema).
