Chronic obstructive pulmonary disease in patients with atrial fibrillation: Insights from the ARISTOTLE trial

Background: Comorbid chronic obstructive pulmonary disease (COPD) is associated with poor outcomes among patients with cardiovascular disease. The risks of stroke and mortality associated with COPD among patients with atrial fibrillation are not well understood. Methods: We analyzed patients from ARISTOTLE, a randomized trial of 18,201 patients with atrial fibrillation comparing the effects of apixaban versus warfarin on the risk of stroke or systemic embolism. Using Cox proportional hazards models, we assessed the associations between comorbid COPD and risk of stroke or systemic embolism and of mortality, adjusting for treatment allocation, smoking history and other risk factors. Results: COPD was present in 1950 (10.8%) of 18,134 patients with data on pulmonary disease history. After multivariable adjustment, COPD was not associated with risk of stroke or systemic embolism (adjusted HR 0.85 [95% CI 0.60, 1.21], p = 0.356). However, COPD was associated with a higher risk of all-cause mortality (adjusted HR 1.60 [95% CI 1.36, 1.88], p < 0.001) and both cardiovascular and non-cardiovascular mortality. The benefit of apixaban over warfarin on stroke or systemic embolism was consistent among patients with and without COPD (HR 0.92 [95% CI 0.52, 1.63] versus 0.78 [95% CI 0.65, 0.95], interaction p = 0.617). Conclusions: COPD was independently associated with increased risk of cardiovascular and non-cardiovascular mortality among patients with atrial fibrillation, but was not associated with risk of stroke or systemic embolism. The effect of apixaban on stroke or systemic embolism in COPD patients was consistent with its effect in the overall trial population. (C) 2015 Elsevier Ireland Ltd. All rights reserved.