Bronchitis typically refers to chronic bronchitis in a clinical setting. Bronchitis is commonly found in middle-aged and older adults, often triggered by prolonged smoking, repeated respiratory infections, and long-term exposure to harmful gases in the air, leading to chronic bronchitis.

Chronic bronchitis is an irreversible inflammatory condition. The frequency of bronchitis episodes increases over time in affected individuals. If bronchitis progresses to an advanced stage without timely medical intervention, it may evolve into more severe chronic clinical conditions like emphysema or chronic pulmonary heart disease. Therefore, it is crucial to take bronchitis seriously and provide appropriate symptomatic treatment.