Abstract 19776: Race and Socioeconomic Status Have Independent Effects on Amputation in Peripheral Arterial Disease (PAD) Patients
Introduction: Black race has been shown to be a risk factor for amputation in PAD. However, race may be a marker for socioeconomic status (SES) or access to care or indicate true biological differences. The aim of this study is to study the interaction of race and SES as a proxy for access to care on amputation risk in PAD patients.
Methods: Patients with PAD in the Veterans Affairs database were identified from 2003-2014 using a validated algorithm. The exposures were race and SES [as measured by percentage of individuals below the poverty line in the patient’s zip code tabulation area (ZCTA)]. Outcomes were incident major amputation risk at 1, 3 and 5 years. The effect of race and SES was analyzed using Cox models to adjust for covariates and test for interaction.
Results: In 208,194 patients with PAD [Males: 98.1%; Black: 16.2%, White: 82.5%], there were 14,981 major amputations [Median follow up 5.2 yrs]. Black veterans were significantly more likely to live in ZCTAs with lower SES. Incident amputation risk declined significantly in higher SES strata within both black and white PAD patients but not in other racial groups (Table 1A). Black patients had a higher amputation risk in each SES stratum as compared to white patients (Table 1A). In Cox models (adjusting for age, gender, race, SES, comorbidities, cholesterol levels, creatinine, and medications) black race was associated with a 43% higher amputation risk as compared to whites [HR 1.43; 95% CI (1.27, 1.62)] while low SES was independently predictive of increased risk of amputation [HR 1.37; 95% CI (1.26, 1.49) for >30.0% vs. <=10.0%] (Table 1B). The test for interaction between race and SES was not significant (LR chunk test p=0.85).
Conclusion: Black veterans have a higher risk of amputation than whites within the same SES strata. Black race and low SES are independently predictive of higher amputation risk in PAD. Further research is needed to elucidate mechanisms leading to increased racial disparity in PAD patients.
Author Disclosures: S. Arya: Research Grant; Modest; AHA Mentored Clinical and Population Research award. C. Long: None. Z.O. Binney: None. A. Khakharia: None. L.P. Brewster: None. P.P. Goodney: None. R.E. Patzer: None. P.W. Wilson: None.
- © 2016 by American Heart Association, Inc.