Living in high-poverty areas is associated with reduced survival in patients with thoracoabdominal aortic aneurysms

Abstract

Objectives: Studies have demonstrated that socioeconomic status, insurance, race, and distance impact clinical outcomes in patients with abdominal aortic aneurysms. The purpose of this study was to assess if these factors also impact clinical outcomes in patients with thoracoabdominal aortic aneurysms (TAAAs).

Methods: We conducted a retrospective review of patients with TAAAs confirmed by computed tomography imaging between 2009 and 2019 at a single institution. Patients' zip codes were mapped to American Community Survey Data to obtain geographic poverty rates. We used the standard U.S. Census definition of high-poverty concentration as >20% of the population living at 100% of the poverty rate. Our primary outcome was overall survival, stratified by whether the patient underwent repair.

Results: Of 578 patients, 575 had zip code data and were analyzed. In both the nonoperative (N = 268) and operative (N = 307) groups, there were no significant differences in age, race, comorbidities, clinical urgency, surgery utilization, or surgery modality between patients living in high-poverty areas (N = 95, 16.4%) vs not. In the nonoperative group, patients from high-poverty areas were more likely to have aneurysm due to dissection (37.5% vs 17.6%, P = .03). In multivariate analyses, patients from high-poverty zip codes had significantly worse nonoperative survival (hazard ratio [HR]: 1.9, 95% confidence interval [CI]: 1.1-3.3, P = .03). In the repair group, high poverty was also a significant predictor of reduced postoperative survival (HR: 1.65, 95% CI: 1-2.63, P = .04). Adding the Gagne Index, these differences persisted in both groups (nonoperative: HR: 1.93, 95% CI: 1.01-3.70, P = .05; operative: HR: 1.62, 95% CI: 1.03-2.56, P = .04). In Kaplan-Meier analysis, the difference in postoperative survival began approximately 1.5 years after repair. Private insurance was predictive of improved postoperative survival (HR: 0.42, 95% CI: 0.18-0.95, P = .04) but reduced nonoperative survival (HR: 2.05, 95% 1.01-4.14, P = .04). Data were insufficient to determine if race impacted survival discretely from poverty status. These results were found after adjusting for age, race, sex, maximum aortic diameter, coronary artery disease, distance from the hospital, insurance, and active smoking. Interestingly, in multivariate regression, traveling greater than 100 miles was correlated with increased surgery utilization (odds ratio: 1.58, 95% CI: 1.08-2.33, P = .02) and long-term survival (HR: 0.61, 95% CI: 0.41-0.92, P = .02).

Conclusions: Patients with TAAAs living in high-poverty areas had significantly more dissections and suffered a nearly doubled risk of mortality compared with patients living outside such areas. These data suggest that these disparities are attributed to the overall impacts of poverty and highlight the pressing need for research into TAAA disparities.

Keywords: Disparities; Distance; Poverty; Survival; Thoracoabdominal aortic aneurysm.