(A06) The Impact of Contextual-Level Social Determinants of Health on Heart Failure Readmission and Mortality in Patients Hospitalized for Heart Failure

Publication Number: 290

Background: Heart failure (HF) is a common cause of hospitalization resulting in high healthcare expenditures. Further, HF readmission rates vary across geographic regions, but little is known of how contextual level factors (i.e., neighborhood social, built, and natural environments) impact HF readmissions and health outcomes.

Objectives: We thus aimed to examine the association between contextual-level social determinants of health (SDoH) and HF readmission and mortality and whether it varies by race and ethnicity.

Methods: We identified patients’ first HF hospitalization using 2016-2022 electronic health records (EHR) data from the OneFlorida+ network. A set of 1,308 contextual-level SDoH factors, capturing social (e.g., food access), built (e.g., hospital density) and natural (e.g., air pollutions) environments, was temporospatially linked to these individuals’ EHR data based on their residential histories. We followed patients from first HF hospitalization for a year to observe HF readmissions and mortality. We employed a two-phase External Exposome-Wide Association Study (ExWAS) approach to identify key contextual-level SDoH factors associated with a composite of HF readmission or mortality. The data was split equally into a discovery set and a replication set and analyzed through logistic regression in phase 1, and then all significant variables were included in a multivariable regression model in phase 2. The results were adjusted for individual demographics and clinical characteristics. Subgroup analyses were conducted by race and ethnicity.

Results: Of 63,937 included individuals, 61% were women with a mean (SD) age of 65 (14) years. Using the ExWAS approach, after removing highly correlated variables, a total of 4 variables remained statistically significant. Neighborhoods with a higher proportion of residents living in poverty (odds ratio [OR] 1.03, 95% confidence interval [CI] 1.01-1.06) and extreme heat (OR 1.05, 95% CI 1.03-1.08) had significantly increased risk of HF readmission or mortality. Areas having more pesticide use (OR 0.96, 95% CI 0.94-0.98), and more winter precipitation (OR 0.97, 95% CI 0.95-0.99) were associated with lower risk of HF readmission or mortality.

Conclusions: Using a data-driven approach, we identified four key contextual-level SDoH associated with HF readmission and mortality: neighborhoods with high levels of poverty, prolonged exposure to extreme heat, less pesticide use, and low levels of precipitation. Future studies are needed to understand the underlying mechanisms of how contextual-level SDoH may impact HF outcomes.