Abstract
BACKGROUND: National social determinant of health (SDoH) studies on gastrointestinal cancers (GIC) have observed single GIC-types for surgery but not across all GIC-types, non-surgical treatments outcomes, or mortality. The Social Vulnerability Index (SVI), a validated large-data SDoH-tool, quantifiably characterizes the interrelatedness of SDoH-impact through dynamic, region-contextualized measures. METHODS: This retrospective cohort study assessed GIC patients (20+ years) between 2013 and 2017 from the Surveillance, Epidemiology, and End Results (SEER) database for total and subcomponent social vulnerability associations across 15 SDoH-variables encompassing themes of socioeconomic status, minority-language status, household composition, and housing-transportation measured by the Social Vulnerability Index (SVI). These are measured and contextualized from all US counties. Univariate logistic and linear regressions of these vulnerability associations with treatment receipt (chemotherapy, radiation, primary surgery) and survival were performed for the entire cohort and across race/ethnicity strata. RESULTS: With increasing overall social vulnerability, 287,248 patients (162,387 [56.5%] male; 185,250 [64.6%] white) demonstrated decreased receipt of chemotherapy (lowest, pancreas-OR, 0.90; 95% CI, 0.88-0.93), radiotherapy (hepatic-OR, 0.87; 95% CI, 0.85-0.89) and surgery (esophagus-OR, 0.90; 95% CI, 0.87-0.92) for 13/14, 10/14, and 8/14 GIC-types, respectively. Survival period decreases upwards of 21.3% (biliary tract: 6.9-5.4 months) were observed across 7/14 GICs. Treatment receipt and survival decreases were exacerbated for non-White patients for 9/14 GICs. Socioeconomic status, minority-language, household composition, and housing-transportation vulnerabilities differentially contributed to these trends. DISCUSSION: Social vulnerability was associated with worse prognostic and treatment disparities, with certain SDoH-types differentially contributing to these detrimental trends per GIC-type while associations were exacerbated among non-White race/ethnic patients. These real-world contexts present actionable targets for further initiatives to combat GIC disparities.