Clinical Phenotypes and Prognostic Heterogeneity of Mild-to-Moderate Chronic Obstructive Pulmonary Disease: A Prospective Community-Based Cohort Study.
BACKGROUND The clinical phenotypes, prognosis, and heterogeneity of mild-to-moderate chronic obstructive pulmonary disease (COPD) have not been systematically evaluated. RESEARCH QUESTION Do different clinical phenotypes of mild-to-moderate COPD have different prognoses? STUDY DESIGN AND METHODS We analysed the bas...