Background: Coronary artery disease (CAD) is one of the main types of cardiovascular disease and is charac-terized by myocardial ischemia as a result of narrowing of the coronary arteries. Objective: To evaluate the impact of chronic obstructive pulmonary disease (COPD) on outcomes in patients with CAD treated by percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG). Methods: We searched PubMed, Embase, Web of Science, and Cochrane Library for observational studies and post-hoc analyses of randomized controlled trials published before Jan 20, 2022, in English. Adjusted odds ratios (ORs), risk ratios (RRs), and hazard ratios (HRs) for short-term outcomes (in-hospital and 30-day all -cause mortality) and long-term outcomes (all-cause mortality, cardiac death, major adverse cardiac events) were extracted or transformed. Results: Nineteen studies were included. The risk of short-term all-cause mortality was significantly higher in patients with COPD than in those without COPD (RR 1.42, 95% CI 1.05-1.93), as were the risks of long-term all-cause mortality (RR 1.68, 95% CI 1.50-1.88) and long-term cardiac mortality (HR 1.84, 95% CI 1.41-2.41). There was no significant between-group difference in the long-term revascularization rate (HR 1.01, 95% CI 0.99-1.04) or in short-term and long-term stroke rates (OR 0.89, 95% CI 0.58-1.37 and HR 1.38, 95% CI 0.97-1.95). Operation significantly affected heterogeneity and combined results for long-term mortality (CABG, HR 1.32, 95% CI 1.04-1.66; PCI, HR 1.84, 95% CI 1.58-2.13). Conclusions: COPD was independently associated with poor outcomes after PCI or CABG after adjustment for confounders. (c) 2023 Elsevier Inc. All rights reserved.