12th May 2024

A 63-year-old man with a 40-pack-year smoking history presents with progressive dyspnea, chronic cough, and frequent chest infections.

A 63-year-old man with a 40-pack-year smoking history presents with progressive dyspnea, chronic cough, and frequent chest infections. He complains that his symptoms are worsening, especially his ability to exercise, which has significantly declined over the past year. On examination, he has prolonged expiration with wheezes and decreased breath sounds. Spirometry shows an FEV1/FVC ratio of less than 0.70 after bronchodilator use.

Which pathophysiological process is most likely to be responsible for his condition?