Abstract Body (Do not enter title and authors here): Background: The impact of neighborhood walkability on peripheral artery disease (PAD) outcomes remains understudied, despite walking being the first line of treatment for PAD and evidence linking walkability to improved health outcomes. We examined the relationship between neighborhood walkability, community distress, and amputation outcomes in patients with PAD who underwent peripheral vascular intervention (PVI).

Hypothesis: Poor walkability and higher community distress are associated with higher amputation risk in patients with PAD, with a potential amplified association in non-White race, given documented worse outcomes.

Methods: This retrospective cohort study used data from Vascular Quality Initiative-linked Medicare database (2015-2019). National Walkability Index (NWI) and Distressed Communities Index (DCI) were used to assess neighborhood walkability and community distress. The primary outcome was 5-year major amputation following PVI. A flexible parametric survival model analyzed the associations between NWI, DCI and amputation risk, accounting for competing risk of death and adjusting for demographics, comorbidities, and PAD severity. All models were stratified by race/ethnicity. Interactions between NWI, DCI and race/ethnicity were tested.

Results: Total 21,641 patients were included. Mean age was 71.1 ± 9.6 years, 60.1% were males, 81.5% White, 13.9% Black, 4.1% other race. Those living in higher NWI neighborhoods were more likely to be Black (28.2% vs. 8.4%, p<0.001) and have advanced PAD (CLTI in 53.9% vs. 45.1%, p<0.001). Higher DCI scores, indicating higher distress, were associated with increased 5-year major amputation risk (sub-hazard ratio [sHR] 1.03 95% CI 1.01-1.05, p=0.001). The impact of walkability on amputation risk varied by race, with Black patients showing higher risk in low NWI neighborhoods (sHR 1.05, 95% CI 1.02-1.08, p=0.001) compared to White patients (sHR 1.00, 95% CI 0.98-1.01, p=0.569). NWI showed a significant interaction by race/ethnicity on amputation outcomes (p=0.036), while DCI did not (p=0.263).

Conclusions: In patients with PAD who underwent PVI, the association between neighborhood walkability and major amputation varied by race. Black patients were more vulnerable to their neighborhood environment, with a higher risk of amputation in areas with lower walkability. Future research should explore impact of targeted interventions based on neighborhood walkability and distress to reduce disparities in PAD outcomes.