Physiologic similarities and differences between COPD and asthma.
The structural and physiologic findings in asthma and COPD appear, on average, and in the extremes of presentation, to be easily distinguished. A closer inspection of the literature reveals that significant overlap exists in individual patients with respect to airway wall thickening and low-attenuation parenchymal regions on CT scans, and in reversibility, airway hyperresponsiveness, lung diffusion, resting and dynamic hyperinflation, lung elastic recoil, exercise response, and a "pharmaceutical volume reduction" effect following therapy with bronchodilators. In particular, the subgroup of COPD patients having an airway-dominant phenotype becomes indistinguishable from asthmatic subjects with reversible disease that evolves into an incompletely reversible pattern.
Sciurba
Frank C
FC
Division of Pulmonary, Allergy and Critical Care Medicine, University of Pittsburgh, 1211 Kaufmann Bldg, Pittsburgh, PA 15213, USA. sciurbafc@upmc.edu
D001249:Asthma / Q000188:drug therapy / Q000235:genetics / Q000503:physiopathology*; D017079:Exercise Tolerance / Q000502:physiology; D005541:Forced Expiratory Volume / Q000502:physiology; D014644:Genetic Variation / Q000235:genetics; D006801:Humans; D008170:Lung Compliance / Q000502:physiology; D010101:Oxygen Consumption / Q000502:physiology; D010641:Phenotype; D029424:Pulmonary Disease, Chronic Obstructive / Q000188:drug therapy / Q000235:genetics / Q000503:physiopathology*; D014797:Vital Capacity / Q000502:physiology