Sex-based differences in outcomes after lower extremity bypass for chronic limb-threatening ischemia

Background and aims: Lower extremity bypass surgery is an effective treatment option for patients with chronic limb-threatening ischemia (CLTI). Recent studies have suggested that sex-based differences may impact patient outcomes following lower extremity revascularization, however, results have been inconsistent.Methods: In this multicenter analysis, we retrospectively identified all infrainguinal bypass procedures performed for CLTI from 2002 to 2021. Patients were separated into two groups based on sex. Primary outcomes were major limb amputation and reintervention for graft patency.Results: Of 843 bypasses performed over the study period, 347 (41.2%) patients were female. Racial/ethnic distribution and medical comorbidities were similar across sex groups. Surgical indications and operative details were also similar between groups, including conduit type (49.9% autogenous), bypass target (65.4% infrageniculate), and concurrent endarterectomy (38.9%). Female and male patients had similar hospital length of stay (6 days [4-9] vs 6 days [4-9]), hospital readmission (25.6% vs 25.0%), and postoperative complications (p=NS each). Female patients had higher major amputation rates (10.1% vs 6.3%, p=0.04) after one year, whereas reintervention rates were similar between groups (26.2% vs 24.6%, p=NS). After accounting for patient factors, female sex (odds ratio [OR] 1.02 [1.00-1.04]), infrageniculate target (OR 1.02 [1.00-1.04]), and bypass for tissue loss (OR 1.02 [1.00-1.04]) were associated with major amputation after bypass (p<0.05 each).Conclusions: Female sex is associated with a small but significant increase major amputation after lower extremity bypass surgery for CLTI, despite similar clinical presentation, medical comorbidities, and operative details. These data support the increasingly recognized sex disparities in peripheral arterial disease.