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How do chronic bronchitis and emphysema contribute to COPD?
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respiratory disease
The bronchioles of the lungs are the site where oxygen is exchanged for carbon dioxide during the process of respiration. Inflammation, infection, or obstruction of the bronchioles is often associated with acute or chronic respiratory disease, including bronchiectasis, pneumonia, and lung abscesses.
Chronic obstructive pulmonary disease (COPD) is a progressive respiratory condition characterized by the combination of emphysema and chronic bronchitis, which together cause irreversible airflow obstruction.123
These two components contribute to COPD in distinct ways:
- Emphysema: This condition involves the destruction of alveolar walls and the loss of elastic tissue in the lungs. This destruction reduces the surface area available for gas exchange and causes the lungs to overinflate, which compresses the small bronchi and increases resistance to airflow, particularly during exhalation.43
- Chronic Bronchitis: This component is characterized by a tendency for excessive mucus production in the airways. This accumulation further obstructs the bronchi, compounding the difficulty in exhaling.21
While these are distinct pathological processes, they frequently occur together—often as a result of tobacco smoking—and both contribute to the hallmark symptoms of COPD, including shortness of breath, reduced ventilatory ability, and general respiratory disability.143