pubmed-article:437307 | pubmed:abstractText | Chronic bronchitis is probably associated with two distinct processes, 'hypersecretory chronic bronchitis' and 'obstructive chronic bronchitis'. These, however, have common causes and typically chronic bronchitis develops as a result of several factors in conjunction. Smoking, air pollution and infection all predispose to chronic bronchitis and elimination of these hazards can slow the progress of the disease. | lld:pubmed |