Which is the most common cause of chronic bronchitis?

The most common cause of chronic bronchitis is cigarette smoking. Chronic bronchitis, characterized by persistent inflammation of the bronchial tubes, leads to increased mucus production and a chronic cough. Cigarette smoke contains numerous harmful chemicals that damage the respiratory epithelium and impair the normal clearing mechanisms of the lungs, which contributes significantly to the development of chronic bronchitis.

Over time, the repeated exposure to smoke results in inflammation, mucus hypersecretion, and narrowing of the airways. This causes breathing difficulties and exacerbates the symptoms of chronic bronchitis. While air pollution, genetic disorders, and asthma can contribute to respiratory issues, they are not as prevalent in causing chronic bronchitis as cigarette smoking. Smoking is responsible for a substantial majority of cases, highlighting its role as the primary risk factor for the disease.