Area Deprivation Index is not predictive of worse outcomes after open lower extremity revascularization

Abstract

ObjectivePrior research has shown that socioeconomic status (SES) is associated with higher rates of diabetes, peripheral vascular disease, and amputation. We sought to determine whether SES or insurance type increases the risk of mortality, major adverse limb events (MALE), or hospital length of stay (LOS) after open lower extremity revascularization. MethodsWe conducted a retrospective analysis of patients who underwent open lower extremity revascularization at a single tertiary care center from January 2011 to March 2017 (n = 542). SES was determined using state Area Deprivation Index (ADI), a validated metric determined by income, education, employment, and housing quality by census block group. Patients undergoing amputation in this same time period (n = 243) were included to compare rates of revascularization to amputation by ADI and insurance status. For patients undergoing revascularization or amputation procedures on both limbs, each limb was treated individually for this analysis. We performed a multivariate analysis of the association between ADI and insurance type with mortality, MALE, and LOS using Cox proportional hazard models, including confounding variables such as age, gender, smoking status, body mass index, hyperlipidemia, hypertension, and diabetes. The cohort with an ADI quintile of 1, meaning least deprived, and the Medicare cohort were used for reference. P values of <.05 were considered statistically significant. ResultsWe included 246 patients undergoing open lower extremity revascularization and 168 patients undergoing amputation. Controlling for age, gender, smoking status, body mass index, hyperlipidemia, hypertension, and diabetes, ADI was not an independent predictor of mortality (P = .838), MALE (P = .094), or hospital LOS (P = .912). Controlling for the same confounders, uninsured status was independently predictive of mortality (P = .033), but not MALE (P = .088) or hospital LOS (P = .125). There was no difference in the distribution of revascularizations or amputations by ADI (P = .628), but there was higher proportion of uninsured patients undergoing amputation compared with revascularization (P < .001). ConclusionsThis study suggests that ADI is not associated with an increased risk of mortality or MALE in patients undergoing open lower extremity revascularization, but that uninsured patients are at higher risk of mortality after revascularization. These findings indicate that individuals undergoing open lower extremity revascularization at this single tertiary care teaching hospital received similar care, regardless of their ADI. Further study is warranted to understand the specific barriers that uninsured patients face.