Racial disparities in outcomes of endovascular procedures for peripheral arterial disease: an evaluation of California hospitals, 2005-2009

Background: Racial/ethnic disparities in treatment outcomes of peripheral arterial disease (PAD) are well documented. Compared with non-Hispanic (NH) whites, blacks and Hispanics are more likely to undergo amputation and less likely to undergo bypass surgery for limb salvage. Endovascular procedures are being increasingly performed as first line of therapy for PAD. In this study, we examined the outcomes of endovascular PAD treatments based on race/ethnicity in a contemporary large population-based study.

Methods: We used Patient Discharge Data from California's Office of Statewide Health Planning and Development to identify all patients over the age of 35 who underwent a lower extremity arterial intervention from 2005 to 2009. A look-back period of 5 years was used to exclude all patients with prior lower extremity arterial revascularization procedures or major amputation. Cox proportional hazards regression was used to compare amputation-free survival and time to death within 365 days. Logistic regression was used for comparison of 1-month myocardial infarction, 1-month major amputation, 1-month all-cause mortality, 12-month major amputation, 12-month reintervention, and 12-month all-cause mortality rates among NH white, black, and Hispanic patients. These analyses were adjusted for age, gender, insurance status, severity of PAD, comorbidities, history of coronary artery angioplasty or bypass surgery, or history of carotid endarterectomy.

Results: Between 2005 and 2009, a total of 41,507 individuals underwent PAD interventions, 25,635 (61.7%) of whom underwent endovascular procedures. There were 17,433 (68%) NH whites, 4,417 (17.2%) Hispanics, 1,979 (7.7%) blacks, 1,163 (4.5%) Asian/Native Hawaiians, and 643 (2.5%) others in this group. There was a statistically significant difference in the amputation-free survival within 365 days among the NH white, Hispanic, and black groups (P < 0.0001); the hazard ratio for amputation within 365 days was 1.69 in Hispanics (95% confidence interval [CI] 1.51-1.90, P < 0.0001) and 1.68 in blacks (95% CI 1.44-1.96, P < 0.001) compared with NH whites following endovascular procedures after adjusting for age, gender, insurance status, comorbidities, severity of PAD, history of coronary artery angioplasty or bypass surgery, or history of carotid endarterectomy. After adjusting for the aforementioned confounders, the first reintervention within 12 months was also significantly associated with race/ethnicity (P = 0.002). Odds ratio for reintervention was 1.17 in blacks (95% CI 1.06-1.30, P = 0.002) and 1.084 in Hispanics (95% CI 1.00-1.16, P = 0.04) compared with NH whites.

Conclusions: In this contemporary large population-based study, we demonstrated that even among matched cohorts Hispanics and blacks have worse amputation-free survival than NH whites following endovascular therapy. Our study also found that Hispanics and blacks are more likely to undergo lower extremity arterial reinterventions than NH whites. Further research is crucial in understanding if higher reintervention rates in Hispanics and blacks are because of more severe disease and/or poor access to proper follow-up care and optimal medical management.