Pre-operative Smoking Cessation Improves Carotid Endarterectomy Outcomes in Asymptomatic Carotid Stenosis Patients.

Abstract

Objective: Smoking cessation has been suggested as having the potential to improve the outcomes of carotid endarterectomy (CEA) and mitigate the risk of long-term stroke in patients with asymptomatic carotid stenosis (ACS). This study aims to compare the peri-operative and long-term outcomes of CEA in ACS patients across different smoking status groups.

Methods: All patients receiving an elective CEA for ACS between 2013 and 2023 were identified in the Vascular Quality Initiative (VQI). Patients with an ipsilateral carotid stenosis <70% and those receiving a concomitant coronary artery bypass graft (CABG) were excluded. Patients were then classified according to their smoking status: never smokers, former smokers (defined as those who have stopped smoking more than 30 days prior to their operation), and current smokers. Patient characteristics and outcomes were compared using the χ² or Fischer's exact test as appropriate for categorical variables and the ANOVA or Kruskal-Wallis test as appropriate for continuous variables. Cox-regression analysis was used to study the association between smoking status and the primary outcomes of long-term stroke and major adverse cardiac events (MACE) defined as the composite outcome of stroke, MI, and/or mortality.

Results: A total of 77,664 patients received a CEA for ACS, of which 19,416 (25%) patients were never smokers, 39,374 (51%) patients were former smokers, and 18,874 (24%) patients were current smokers. Patients in the three groups had similar rates of perioperative stroke (p=0.79), myocardial infarction (p=0.07), mortality (p=0.23), and MACE (p=0.17). At 18-month follow up, former and never smokers had similar rates of stroke (former 0.9% vs never 0.8%, p=0.92), with former smokers exhibiting a lower stroke risk than current smokers (former 0.9% vs current 1.5%, p=0.001). At 18 months, former smokers had a significantly lower rate of MACE compared to current smokers (former 11.8% vs current 13.2%, p=0.03), but a higher rate compared to never smokers (former 11.8% vs never 8.7%, p<0.001). On multivariate Cox-regression analysis, compared to current smokers, former smokers were independently associated with a lower risk of stroke (HR 0.68, 95% CI 0.53-0.87, p=0.002), mortality (HR 0.79, 95% CI 0.74-0.84, p<0.001), and MACE (HR 0.77, 95% CI 0.70-0.83, p<0.001). No difference in long-term stroke risk was observed between former and never smokers (HR 1.06, 95% CI 0.82-1.38, p=0.65).

Conclusion: This study demonstrates that preoperative smoking cessation in ACS patients significantly reduces the risk of stroke, mortality, and MACE following CEA compared to continued smoking, aligning their outcomes more closely with those of never smokers. Optimizing ACS patients prior to surgery should include smoking cessation counseling. Vascular surgeons play a critical role in encouraging smoking cessation, as their guidance can significantly improve patient outcomes following CEA.