Impact of smoking cessation on long term mortality in patients undergoing percutaneous coronary intervention.

Abstract

Introduction: Cigarette smoking is a well-established modifiable risk factor for coronary artery disease (CAD). Smoking cessation is an essential component of secondary prevention and is associated with significant mortality benefit in both stable CAD and post-acute coronary syndrome (ACS). Methods: Patients undergoing PCI from the Melbourne Interventional Group registry (2005-2018) were analysed. Patients were divided into four categories based on their smoking status: never-smokers (NS), ex-smokers (ES), recent-quitters (RQ) or persistent smokers (PS). The primary outcome was long-term mortality determined via National Death Index (NDI) linkage. Results: Among the 28,093 patients included, 6,479 (23.1%) were female. 8,380 (29.8%) patients were NS, 12,337 (43.9%) were ES, 3,536 (12.6%) were RQ and 3,840 (13.7%) were PS. Cox-proportional hazards modelling revealed that compared with NS, PS was an independent predictor of long-term mortality (HR 1.92, 95% CI 1.69-2.17; p<0.001) while smoking cessation post PCI (RQ) significantly reduced this hazard (HR 1.30, 95% CI 1.12-1.50; p<0.001). Conclusion: In a large contemporary cohort of patients undergoing PCI, there was an incremental risk of long-term mortality ranging from ex-smokers, recent quitters with the highest risk observed in persistent smokers. These findings in a contemporary cohort of patients confirm quitting smoking following PCI is associated with a lower risk of long-term mortality.