16th February 2025

A 55-year-old male is an inpatient on the Respiratory ward having been admitted four days ago with breathlessness and a cough productive of green sputum.

A 55-year-old male is an inpatient on the Respiratory ward having been admitted four days ago with breathlessness and a cough productive of green sputum. He has had similar episodes before but has never seen a doctor for them. He has a 30-pack-year smoking history and a background of anxiety, for which he takes sertraline.

On examination, he has bilateral wheeze. His oxygen saturations are 96% on 1 L via nasal cannulae, and his respiratory rate is 22.

Baseline spirometry: FEV1 2.4 L (61% predicted), FVC 4.5 L (90% predicted), FEV1/FVC ratio 53%.

Spirometry following 5 mg nebulised salbutamol: FEV1 3.4 L (87% predicted), FVC 4.6 L (92% predicted), FEV1/FVC ratio 73%.

What is the most likely primary cause of his long-term symptoms?

Select the SINGLE most appropriate option from the list below. Select ONE option only.