Smoking Cessation Duration is associated with the risk of amputation after Revascularization for Chronic Limb-Threatening Ischemia.

Introduction: Although smoking cessation has been shown to improve outcomes after lower extremity revascularization (LER), the impact of cessation duration has not been well defined. This study investigates the impact of two cessation durations on LER outcomes in patients with chronic limb-threatening ischemia (CLTI).

Methods: The Peripheral Vascular Intervention, Infrainguinal Bypass, and Suprainguinal Bypass modules of the Vascular Quality Initiative (VQI) were utilized to identify patients whose first recorded LER occurred between 2016-2024 for CLTI. Former smokers (FS) were divided into 2 groups based on the duration of smoking cessation. Recent FS had quit between 1-9 months prior to LER and 1-year FS had quite between 9-21 months to coincide with the standard follow up of the VQI. FS that quit more than 21 months before surgery were excluded. Two separate propensity score matches based on preoperative variables were performed at a 3:1 ratio, one of current smokers (CS) to recent FS and the other of CS to 1-year FS. Perioperative outcomes were compared along with Kaplan-Meier analysis for 1-year outcomes.

Results: There were 42,896 (84.7%) patients with current smoking (CS) within a month of surgery, 4,875 (11.4%) recent FS, and 2,885 (5.7%) 1-year FS. Both groups of FS were significantly more likely to be older, and have more cardiovascular comorbidities and prior revascularization procedures compared to CS. After matching, baseline characteristics were not different. There were no significant differences in perioperative complications between CS and recent FS or 1-year FS. Long-term outcomes were no different between CS and recent FS. However, patients in the 1-year FS had significantly less major amputation compared to CS with no difference in thrombosis, reintervention, or mortality. On regression analysis, former smoking between 9-21 months was independently associated with lower major amputation compared to current smoking (HR = 0.72 [0.58-0.90]). Factors associated with higher major amputation included male sex (HR = 1.23 [1.02-1.48]), black race (HR = 1.52 [1.25-1.86]), diabetes (HR = 1.59 [1.28-1.97]) and end-stage renal disease (HR = 2.08 [1.61-2.70]).

Conclusion: In this study, former smokers and current smokers had no difference in perioperative outcomes after LER for CLTI. Smoking cessation for a period of 9-21 months prior to LER, but not less than 9 months, was independently associated with decreased long-term major amputation compared to current smoking. Patients undergoing LER for CLTI may need to sustain smoking cessation for 2 years to begin experiencing measurable benefit with respect to limb salvage.