A 62-year-old man is evaluated for declining exercise capacity over the past year

A 62-year-old man is evaluated for declining exercise capacity over the past year. He was diagnosed with moderate COPD 3 years ago. His symptoms had previously been well controlled with tiotropium and as-needed albuterol. He has not had any hospitalizations. He is adherent to his medication regimen, and his inhaler technique is good. He quit smoking 2 years ago. All immunizations are up to date, including influenza and pneumococcal vaccination. A chest radiograph performed 3 months ago for increased cough and sputum production was normal. Pulmonary function testing performed 3 years ago showed an FEV1 of 58% of predicted, an FEV1/FVC ratio of 60%, and a DLCO of 85% of predicted.
On physical examination, vital signs are normal. Oxygen saturation is 93% breathing ambient air. No jugular venous distention is noted. The lungs are clear. Cardiac examination reveals normal heart sounds. There are no murmurs. No edema is noted.
Which of the following is the most appropriate management?

A Add roflumilast
B Obtain complete pulmonary function tests
C Perform chest CT
D Repeat spirometry
E Start oxygen therapy

Ans:D Repeat spirometry