This is a single-center Phase IIa randomized double-blind crossover study in smokers with and without chronic obstructive pulmonary disease (COPD) to test whether dual antiplatelet therapy (aspirin 81mg and clopidogrel 75mg) improves pulmonary perfusion (i.e. blood flow in the lungs) compared to placebo.~We will enroll 30 subjects (20 with COPD, 10 without) who will each take part for 6 weeks. Participants and researchers will be blinded, they will not know which medications they are on first. Each participant will be asked to take aspirin and clopidogrel together for 2 weeks and also matching placebos for 2 weeks, with a 2 week washout period in between. Pulmonary blood flow will be evaluated with a contrast-enhanced CT scan of the chest two times over the 6 week study.
This is a 6 week crossover study in smokers with and without COPD to evaluate whether 2 weeks of dual antiplatelet therapy (aspirin 81mg and clopidogrel 75mg) improves pulmonary perfusion (i.e. blood flow in the lungs measured on a contrast CT scan) compared to placebo.