Do differences in hospital and surgeon quality explain racial disparities in lower-extremity vascular amputations?

OBJECTIVE To understand whether racial disparities in surgery for lower-extremity arterial disease are minimized by high-quality providers, or instead, differential treatment of otherwise similar patients pervades all settings. SUMMARY BACKGROUND DATA Black patients are substantially more likely than whites to undergo amputation rather than revascularization for lower-extremity arterial disease. Because their care is disproportionately concentrated among a small share of providers, some have attributed such disparities to the quality and capacity of these sites. METHODS We evaluated all 86,865 white or black fee-for-service Medicare beneficiaries 65 and older who underwent major lower-extremity vascular procedures. Using generalized linear mixed models with random effects, we computed risk-adjusted odds of amputation by race overall, and after serial substratification by salient patient and provider characteristics. RESULTS Blacks were far more likely to undergo amputation (45% vs. 20%). Their procedures were performed more often by nonspecialists (41% vs. 27%; P < 0.001), in low-volume hospitals (40% vs. 32%; P < 0.001), with high amputation rates (53% vs. 29%; P < 0.001). Controlling for differences in comorbidity, disease severity, and surgeon and hospital performance, blacks' odds of amputation remained 1.7 times greater (95% confidence interval: 1.6-1.9). Even among highest-performing providers-vascular specialists in high-volume, urban teaching hospitals with angioplasty facilities-racial gaps persisted (risk-adjusted amputation rates: 7% for blacks vs. 4% for whites, P < 0.001; odds ratio: 1.8, 95% confidence interval: 1.5-2.1). CONCLUSIONS Black patients with critical limb ischemia face significantly higher risk of major amputation, even when treated by providers with highest likelihoods of revascularization. Increased referral to high-performing providers might increase limb-preservation, but cannot eliminate disparities until equitable treatment can be ensured in all settings.