To distinguish the two diseases of chronic bronchitis and asthma, you can look at the etiology, clinical symptoms and age of onset. 1. Etiology: chronic bronchitis is mainly related to pathogen infection and external stimuli, long-term smoking patients have a higher incidence than non-smokers, some dust and chronic lung disease can also cause chronic bronchitis. And asthma is mainly related to genetic and environmental factors. 2. Clinical symptoms: chronic bronchitis is mainly characterized by recurrent coughing, sputum and wheezing, and most of them have a history of smoking or long-term exposure to harmful gas particles. Asthma is mainly characterized by recurrent chest tightness, wheezing or coughing, and most of them have a history of allergy or allergic rhinitis. 3. Age of onset: Chronic bronchitis is mainly found in the elderly, especially those who have been smoking for a long time. Asthma often starts at a young age, such as children and adolescents. The difference between chronic bronchitis and asthma is still very big, but both belong to the same chronic diseases, mainly to prevent the main, in the onset of timely medical treatment.