Racial Disparity in Perioperative Aspirin Utilization Impacts Survival of Black Patients Undergoing Lower Extremity Bypass Surgery

Aspirin is known to be protective against major adverse cardiovascular events in peripheral arterial disease patients, both before and after undergoing lower extremity bypass (LEB). Racial and ethnic disparities in LEB outcomes do exist in the literature; however, little is mentioned regarding racial differences in perioperative aspirin utilization in this cohort. We aim to investigate the existence and possible impact of racial and ethnic disparities in perioperative aspirin usage in patients undergoing LEB. All patients undergoing LEB for claudication or critical limb-threatening ischemia (CLTI) between January 2012 and October 2023 were identified in the Vascular Quality Initiative database. Patients were stratified into three ethno-racial groups: non- Hispanic White (NHW), non-Hispanic Black (NHB), and Hispanic. Patients not receiving aspirin due to medical contraindications or noncompliance were excluded. ANOVA and χ2 tests analyzed differences for baseline characteristics. Logistic regression analysis assessed differences in preoperative aspirin usage. Cox regression analysis analyzed 1-year mortality, and backward stepwise selection was implemented to identify significant variables for inclusion in the final models. A sub-analysis was performed to assess the impact of aspirin prescribed on discharge on 1-year survival. A total of 47,139 patients were included (NHW: 35,789; 75.9%; NHB: 8794; 18.7%; Hispanic: 2556; 5.4%). NHW patients were more likely to be older and male. NHB and Hispanic patients were more likely to be hypertensive, diabetic, on dialysis, and presenting with CLTI. After adjusting for patient comorbidities and demographics, NHB and Hispanics were less likely to be receiving aspirin before undergoing LEB compared to NHW (OR, 0.89; 95% CI, 0.81-0.98 and OR, 0.87; 95% CI, 0.77-0.98; P < .05) (Table I). After excluding patients with contraindications to aspirin intake, NHB were also prescribed less aspirin on discharge compared to NHW (85.32% vs 86.63%; P = .014). Fig 1 shows discharge aspirin being an independent predictor of 1-year survival post-LEB. NHB and Hispanic patients had lower 1-year mortality after LEB compared to NHW (HR, 0.91; 95% CI, 0.82-1.00 and HR, 0.81; 95% CI, 0.68-0.96; P < .05]. However, results of the sub-analysis show that NHB not receiving aspirin on discharge have 24% higher risk of 1-year mortality compared to NHW (HR, 1.24; 95% CI, 1.04-1.47). Racial disparities exist in perioperative aspirin utilization in patients undergoing LEB, where NHB patients are less likely to receive aspirin compared to NHW patients. Even though NHB patients have significantly lower risk of 1-year mortality after LEB, their survival advantage disappears if aspirin is not prescribed postoperatively.TableUtilization of aspirin and 1-year mortality in LEB patients stratified by race and ethnicityOR/HR (95% CI)P valueNHB vs NHW Preoperative aspirin0.89 (0.81-0.98).013 One-year mortality (overall)0.91 (0.82-1.00).041 One-year mortality (Both NHW and NHB receive DC-ASA)0.88 (0.80-0.98).016 One-year mortality (Only NHW (but not NHB) receive DC-ASA)1.24 (1.04-1.47).017 One-year mortality (Neither NHW nor NHB receive DC-ASA)1.03 (0.84-1.26).770Hispanic vs NHW Preoperative aspirin0.87 (0.77-0.98).021 One-year mortality0.81 (0.68-0.96).016NHB vs Hispanic Preoperative aspirin1.04 (0.91-1.18).589 One-year mortality1.06 (0.90-1.26).484CI, Confidence interval; DC-ASA, aspirin on discharge; HR, hazard ratio; NHB, non-Hispanic Black; NHW, non-Hispanic White; OR, odds ratio. Open table in a new tab