Background: Phenotypic characterization of patients with COPD may have potential prognostic and therapeutic implications. Available information on the relationship between emphysema and the clinical presentation in patients with COPD is limited to advanced stages of the disease. The objective of this study was to describe emphysema presence, severity, and distribution and its impact on clinical presentation of patients with mild to moderate COPD.
Methods: One hundred fifteen patients with COPD underwent clinical and chest CT scan evaluation for the presence, severity, and distribution of emphysema. Patients with and without emphysema and with different forms of emphysema distribution (upper/lower/core/peel) were compared. The impact of emphysema severity and distribution on clinical presentation was determined.
Results: Fifty percent of the patients had mild homogeneously distributed emphysema (1.84; 0.76%-4.77%). Upper and core zones had the more severe degree of emphysema. Patients with emphysema were older, more frequently men, and had lower FEV(1)%, higher total lung capacity percentage, and lower diffusing capacity of the lung for carbon monoxide. No differences were found between the clinical or physiologic parameters of the different emphysema distributions.
Conclusions: In patients with mild to moderate COPD, although the presence of emphysema has an impact on physiologic presentation, its severity and distribution seem to have little impact on clinical presentation.