Preoperative smoking cessation impacts presentation and neurologic outcomes of carotid endarterectomy.

Abstract

Objective: Smoking increases perioperative mortality after carotid endarterectomy (CEA), but the effect of smoking cessation duration on outcomes remains unclear. This study evaluates how different durations of smoking cessation impact long-term outcomes after CEA in the Vascular Quality Initiative (VQI).

Methods: Patients in the VQI database undergoing CEA (2012-2023) with "current smoking" were compared to 3 groups of former smokers based on the duration of quitting: <9, 9-21, or >21 months before CEA. These intervals align with VQI's follow-up window and permit assessment of specific cessation durations. Patients with missing or changed smoking status at follow-up were excluded. Long-term outcomes were compared. Regression analysis was performed to assess independent associations with outcomes.

Results: There were 20,390 current smokers, 3,437 former <9m, 2,368 former 9-21m, and 6,370 former >21m patients identified. Former smokers were more likely to be older and Hispanic, and were more likely to have diabetes, chronic kidney disease, and cardiac disease while current smokers were more likely to have chronic obstructive pulmonary disease (COPD). Current smokers were more likely to present with a stroke and undergo surgery urgently. After a mean follow-up of 415 days, smokers had a significantly higher rate of mortality (<9m, 4.8% vs 7.1%, p<0.001; 9-21m, 5.6% vs 7.1%, p=0.007; >21m, 5.1% vs. 7.1%, p<0.001), or transient ischemic attack (TIA) or stroke (<9m, 0.8% vs 1.3%, p=0.041; 9-21m, 0.7% vs 1.3%, p=0.015; >21m, 0.8% vs. 1.3%, p=0.005). Kaplan-Meier analysis revealed only former 9-21m (p=0.04) and former >21m (p=0.02) but not former <9m (p=0.1) had significantly lower long-term TIA or stroke compared with smokers. On regression, only former >21m was independently associated with lower long-term TIA or stroke (HR=0.71[0.52, 0.96]), with similar statistically non-significant trend among former <9m (HR=0.71 [0.48, 1.05]) and former 9-21m (HR=0.63[0.38, 1.05]) smokers. Female sex, diabetes, and symptomatic presentation demonstrated consistent association with increased risk of long-term TIA or stroke regardless of cessation duration.

Conclusion: A smoking cessation duration of greater than 21 months prior to CEA is associated with decreased long-term ipsilateral neurologic events. These findings suggest that sustained preoperative and postoperative smoking cessation may be necessary to detect statistically significant risk reduction in neurological events.