Race and outcomes of lower extremity revascularization for critical limb ischemia

Abstract

INTRODUCTION: Studies have shown poor outcomes following infra-inguinal bypass in African-American patients compared with Caucasians. The aim of this study was to investigate the racial disparity in a cohort of patients who underwent infra-inguinal bypass surgery at our institute. METHODS: We retrospectively reviewed data of all patients who underwent infra-inguinal bypass performed with autogenous vein grafts for symptomatic peripheral artery disease from 2007–2014 at a single tertiary care institution. Univariate (Chi-square test and Student's t-test) and multivariable analyses (logistic and Cox regression) were used to evaluate the association between race and the outcomes of mortality, primary and primary-assisted patency, and limb loss following infra-inguinal bypass. RESULTS: The study included 412 autogenous bypass grafts, of which 312 (76%) were performed in Caucasians and 100 (24%) in African-Americans. African-American patients had significantly higher comorbidities including diabetes (74% vs. 57%, P = 0.002) and chronic kidney disease on dialysis (22% vs. 10%, P = 0.002) as compared with Caucasians. The majority of patients in both groups underwent bypass for critical limb ischemia (88% vs. 87%, P = 0.71). Mean follow-up time was 1.8 ± 1.8 years. The rates of major amputation were not significantly different between two groups (17% vs. 10%, P = 0.07). Moreover, no significant differences in primary and primary assisted were seen between African-Americans and Caucasians (hazard ratio [HR] [95% confidence interval [CI]: 0.90 [0.56–1.44], P = 0.66 and 1.21 [0.72–2.03], P = 0.46), respectively. Hyperlipidemia was shown to be significantly associated with primary-assisted patency, while diabetes was a significant risk factor for limb loss [HR (95% CI): 2.73 (1.26–5.93), P = 0.01). CONCLUSION: In this study, there were no significant differences in bypass patency and limb salvage between African-Americans and Caucasians following infra-inguinal bypass over 5-year follow-up. These findings suggest that the outcomes of infra-inguinal bypass can be optimized in African-American patients with the use of autogenous vein conduits and comprehensive medical management including the control of diabetes and hyperlipidemia.