The phenotype of concurrent chronic bronchitis and frequent exacerbations in patients with severe COPD attending Swedish secondary care units.
Chronic bronchitis and previous exacerbations are both well-known risk factors for new exacerbations, impaired health-related quality of life, and increased mortality in COPD. The aim of the study was to characterize the phenotype of concurrent chronic bronchitis and frequent exacerbation in severe COPD.