Sex Differences in Arterial Grafting in Patients Undergoing Dialysis and Coronary Artery Bypass Grafting

Importance: Patients with kidney failure undergoing dialysis have increased morbidity and mortality when undergoing coronary artery bypass grafting (CABG). Women also have increased morbidity and mortality compared with men after coronary revascularization; however, outcomes for female patients with kidney failure undergoing dialysis remain understudied, particularly with multiarterial grafting (MAG) during CABG. Objective: To compare 5-year survival following arterial grafting among men vs women with kidney failure undergoing dialysis. Design, Setting, and Participants: This retrospective, population-based cohort study used United States Renal Data System data from October 15, 2015, to December 31, 2020, to identify patients receiving hemodialysis who underwent isolated CABG. Patients receiving a kidney transplant before CABG were excluded. Data analysis was performed from December 1, 2024, to December 31, 2025. Exposure: CABG graft patterns were divided as left internal mammary artery (LIMA) grafting plus saphenous vein grafting (SVG) vs SVG only and LIMA grafting vs MAG. Main Outcomes and Measures: The main outcome of interest was 5-year mortality in risk-adjusted groups. Cohorts were compared in 2 analyses: arterial grafting in men vs SVG only in men, and arterial grafting in women vs SVG only in women. Outcomes in men and women were then directly compared within each choice of conduit. Results: There were 15 215 patients in the total unadjusted cohort, with 10 466 men (68.8%) and 4749 women (31.2%) (median [IQR] age, 65.3 [57.2-71.5] years). After inverse probability of treatment weighting adjustment, LIMA grafting was associated with better 5-year survival than SVG only in both men (32.0% [95% CI, 30.7%-33.3%] vs 27.3% [95% CI, 23.2%-32.2%]; P < .001) and women (30.7% [95% CI, 28.9%-32.6%] vs 25.3% [95% CI, 20.3%-31.5%]; P = .002). LIMA grafting was not associated with a survival benefit at 5 years compared with MAG in men (32.1% [95% CI, 30.8%-33.4%] vs 35.9% [95% CI, 29.2%-44.1%]; P = .45) or women (30.6% [95% CI, 28.9%-32.5%] vs 17.3% [95% CI, 9.9%-30.5%]; P = .08). Comparing sexes by grafting type, men had significantly better 5-year survival than women following LIMA grafting overall (32.1% [95% CI, 30.8%-33.4%] vs 30.5% [95% CI, 28.7%-32.5%]; P < .001) and following LIMA grafting among patients who survived to hospital discharge (34.0% [95% CI, 32.7%-35.5%] vs 33.7% [95% CI, 31.8%-35.7%]; P < .001). Men had significantly better 5-year survival compared with women following MAG (38.5% [95% CI, 32.1%-46.2%] vs 17.0% [95% CI, 9.2%-31.2%]; P = .002). There was no significant 5-year survival difference between men and women among those who received SVG only (28.4% [95% CI, 24.3%-33.2%] vs 25.2% [95% CI, 20.3%-31.2%]; P = .21). Conclusions and Relevance: Although sample sizes were small in some subgroups, female patients were not associated with a survival benefit from arterial grafting compared with their male counterparts. Although both men and women were associated with better long-term survival following LIMA grafting, men appeared to have better long-term survival than women following LIMA grafting and MAG.