Social Vulnerability as a Neighborhood-Level Determinant of Pancreatic Cancer Survivorship: A National Analysis of Veterans Affairs Patients.

BACKGROUND

Veterans Affairs (VA) patients participate within the largest USA equal-access healthcare system, though still experience cancer mortality disparities by social determinants. The Social Vulnerability Index (SVI)-measuring community poverty, minority status, housing, and transportation-has delineated gradients in cancer care utilization and outcomes. We therefore assessed relationships between SVI and mortality in veterans with pancreatic ductal adenocarcinoma (PDAC).

PATIENTS AND METHODS

Records of patients with stage I-III PDAC diagnosed January 2005-December 2018 were abstracted from the VA Corporate Data Warehouse. Addresses were geocoded to SVI. Mann-Whitney U and chi-squared tests compared baseline characteristics. Overall survival (OS) was compared using Kaplan-Meier and multivariable Cox proportional hazards methods.

RESULTS

A total of 1778 patients were evaluated, of which 570 (32%) underwent surgical resection. A total of 516 (29%) patients originated from census tracts in the highest SVI quartile. These patients were more likely Black (38% vs 13%), unemployed (49% vs 35%), and metropolitan-based (87% vs 76%; all p < 0.001). Over a median follow-up of 8.7 months, median OS was 9.5 months versus 10.2 months for high and low SVI groups, respectively (log-rank p = 0.03). In the resected cohort, high and low SVI groups reflected a median OS of 18.2 months versus 23.1 months, respectively (log-rank p < 0.01). High SVI remained independently associated with mortality for resected patients only (hazard ratio [HR] 1.4, p < 0.01).

CONCLUSIONS

High SVI was associated with poorer prognosis after PDAC resection. Acknowledging a need to identify mechanisms, SVI has potential use in triaging PDAC survivorship interventions in veterans.