Smoking Predicts Mortality in Asymptomatic Patients Undergoing Carotid Endarterectomy but Not Carotid Artery Stenting or Transcarotid Artery Revascularization

Abstract

Background: To assess the influence of smoking status on mortality for individuals undergoing intervention for asymptomatic carotid artery stenosis.

Methods: The Vascular Quality Initiative database was queried from 2003 to 2021 to identify patients undergoing interventions for asymptomatic carotid artery stenosis with carotid endarterectomy (CEA), transfemoral carotid stenting (TFCAS), or transcarotid artery revascularization (TCAR). Patients were grouped into 3 cohorts: never, former, or active smokers. Active smokers were those who smoked tobacco within 1 month of their procedure, whereas former smokers had quit at least 1 month prior. Propensity matching was then performed adjusting for demographics, comorbidities, preoperative medications, and additional risk factors including anatomic risk, urgency, anesthesia modality, and degree of stenosis. The primary outcomes were 30-day and 1-year mortality. We also evaluated 30-day incidences of transient ischemic attack, stroke, and other complications. Multivariate logistic regression was used to identify independent predictors of mortality.

Results: We identified 63,651 patients who underwent carotid artery interventions for asymptomatic stenosis: 54,953 received CEA, 3,486 underwent TFCAS, and 5,212 had TCAR. After propensity score matching, no significant differences persisted in preoperative demographics and risk factors. After CEA, active smokers exhibited significantly higher rates of 30-day (0.86% vs. 0.53%, P = 0.021) and 1-year (4.14% vs. 2.58%, P < 0.001) mortality compared to never smokers. Former smokers also had an increased 1-year mortality compared to never smokers (4.28% vs. 3.69%, P = 0.023), but no significant difference in 30-day mortality. Active smokers also had an increased risk of postoperative myocardial infarction after CEA compared to former smokers (0.57% vs. 0.35%, P = 0.013). No significant differences were observed in mortality between smoking statuses after TFCAS or TCAR. Apart from a reduction in stroke rate in active smokers compared to former smokers in TFCAS (1.51% vs. 3.14%, P = 0.046), no other significant differences were noted in any of the secondary outcomes. On multivariate logistic regression analysis, active smoking was independently predictive of 30-day (odds ratio [OR] 1.44, 95% confidence interval [CI]: 1.05-1.97) and 1-year mortality (OR 1.52, 95% CI: 1.32-1.76), and former smoking was predictive of 1-year mortality (OR 1.26, 95% CI: 1.12-1.42) following CEA.

Conclusion: Smoking status is an independent predictor of mortality following CEA in asymptomatic patients, but not in either stenting modality. Our findings suggest a potential benefit of postponing elective CEA in appropriately selected asymptomatic patients until at least 1 month of smoking cessation is attained.