Persistent and Newly Developed Chronic Bronchitis Are Associated with Worse Outcomes in Chronic Obstructive Pulmonary Disease.

Rationale: Chronic bronchitis is, by definition, a chronic condition, but the development and remission of this condition in cigarette smokers with or without chronic obstructive pulmonary disease (COPD) are poorly understood. Also, it is unclear how the persistence or new development of chronic bronchitis affects symptoms and outcomes.

Objectives: To ascertain the relationship between smoking status and the presence or absence of chronic bronchitis and the subsequent effects on symptoms and outcomes.