Impact of Cigarette Smoking on Extent of Coronary Artery Disease and Prognosis of Patients With Non–ST-Segment Elevation Acute Coronary Syndromes: An Analysis From the ACUITY Trial (Acute Catheterization and Urgent Intervention Triage Strategy)

Abstract

This study sought to evaluate the short- and long-term outcomes for smokers with non-ST-segment elevation acute coronary syndromes (NSTE-ACS). Smoking has been associated with the "paradox" of reduced mortality after acute myocardial infarction (MI). This is thought to be due to favorable baseline characteristics and less diffuse coronary artery disease (CAD) among smokers. In the ACUITY (Acute Catheterization and Urgent Intervention Triage Strategy) trial, 13,819 patients (29.1% smokers) with moderate- to high-risk NSTE-ACS underwent angiography and, if indicated, revascularization. Smokers were significantly younger and had fewer comorbidities than nonsmokers. Incidence of death and MI were comparable at 30 days, although smokers had significantly reduced risks of 30-day major bleeding (hazard ratio [HR]: 0.80, 95% confidence interval [CI]: 0.67 to 0.96; p = 0.016) and 1-year mortality (HR: 0.797, 95% CI: 0.65 to 0.97; p = 0.027). After correction for baseline and clinical differences, smoking was no longer predictive of major bleeding (odds ratio: 1.06, 95% CI: 0.86 to 1.32; p = 0.56) and was associated with higher 1-year mortality (HR: 1.37, 95% CI: 1.07 to 1.7; p = 0.013). This pattern of reversed risk after multivariable correction held true for those smokers requiring percutaneous coronary intervention. Core laboratory angiographic analysis showed that smokers and nonsmokers were comparable in terms of the extent of CAD, Thrombolysis In Myocardial Infarction flow, myocardial blush, and the presence of thrombi. In contrast to the paradox previously described in ST-segment elevation MI, our analysis finds smoking to be an independent predictor of higher 1-year mortality in patients presenting with NSTE-ACS, and our angiographic study demonstrates CAD in smokers that is comparable to that in nonsmokers but evident ∼1 decade earlier. (Acute Catheterization and Urgent Intervention Triage Strategy [ACUITY]; NCT00093158).