B96-03 Neighborhood Environmental and Social Determinants of Sepsis Vulnerability and Mortality

Rationale Social determinants of health are established drivers of health outcomes, yet their role in sepsis remains unclear. The California Healthy Places Index (HPI2) aggregates community-level factors across economic, educational, environmental, housing, and social domains. We hypothesized that lower HPI2 scores, reflecting greater neighborhood disadvantage, would be independently associated with higher illness severity and short-term mortality in sepsis. Methods We conducted a retrospective study of 4,598 adults hospitalized with sepsis (Sepsis-3 criteria) at UC San Diego Health from January 2021 to April 2023. Patients were geocoded by ZIP code to HPI2 composite and domain-specific scores. Multivariate logistic and linear regressions assessed associations between neighborhood-level determinants and clinical outcomes, adjusting for age, sex, race, DNR status, baseline comorbidity burden (weighted Charlson Comorbidity Index), and ICU transfer. The primary outcome was short-term mortality (in-hospital death or discharge to hospice), and secondary analyses evaluated associations with baseline physiologic and comorbidity burden. Results Higher neighborhood pollution, within the HPI2 environmental domain, was independently associated with increased odds of short-term mortality (OR 1.22, p = 0.045), while DNR status, ICU transfer, and older age remained the strongest clinical predictors of mortality. The HPI2 education domain, which reflects community-level educational attainment and school enrollment, differed significantly by race (p < 0.001), with lower neighborhood education scores among Black, American Indian/Alaska Native, Native Hawaiian/Pacific Islander, and Mixed/Other Race patients compared with White and Asian patients. Across domains, lower neighborhood percentiles in environmental quality, housing burden, economic security, and healthcare access were consistently associated with higher baseline physiologic severity (all q < 0.04), persisting after adjusting for demographics and insurance type. Conclusion Neighborhood disadvantage across environmental, housing, economic, and healthcare domains was associated with greater baseline comorbidity burden, with higher environmental pollution specifically predicting increased short-term mortality. Although race was not a direct predictor, historically minoritized groups disproportionately resided in neighborhoods with lower HPI2 scores and greater environmental burden. These findings suggest that structural and environmental disadvantage amplify sepsis severity and vulnerability, underscoring the need to incorporate neighborhood context into sepsis risk assessment and prevention strategies. This abstract is funded by: UC San Diego SOM Summer Research Scholarship