Colin is a 65-year old gentleman. He presents to your clinic with complaints of a chronic cough with occasional purulent sputum. He also reports breathlessness, which has recently limited his ability to do his manual work. He can no longer climb the stairs without getting short of breath and he has also noticed it even when he plays with his grandson. He is an ex-smoker with a 40-year pack history. You request a spirometry test as you suspect he may have COPD.
These are the spirometry results following administration of a bronchodilator. How would you interpret this?