Association Between Social Determinants of Health and Readmission Outcomes in Heart Failure: A Retrospective Cohort Study Using Medical Information Mart for Intensive Care IV (MIMIC-IV)

Background: Heart failure remains a major contributor to hospital readmissions and healthcare burden in the United States. Social determinants of health may influence post-discharge outcomes, yet their role among critically ill patients is not fully characterized. Objective: To evaluate the association between selected social determinants of health and 30-day readmission among critically ill patients with heart failure. Methods: This retrospective cohort study used the Medical Information Mart for Intensive Care IV (MIMIC IV) version 3.1 database. Adult patients with heart failure admitted to the intensive care unit were identified using diagnosis codes. The primary outcome was 30-day hospital readmission. Exposures included insurance type, marital status, and race. Multivariable logistic regression was performed, adjusting for age, sex, Charlson Comorbidity Index, Sequential Organ Failure Assessment score, and length of stay. Results: A total of 16,324 patients were included. The 30-day readmission rate was 17.6%. Black patients had higher odds of readmission compared to White patients, aOR: 1.37, 95% CI: 1.21 to 1.56, p<0.001, and Hispanic patients also had higher odds, aOR: 1.31, 95% CI: 1.04 to 1.64, p=0.020. Private insurance was associated with lower odds compared to Medicare (aOR: 0.83, 95% CI: 0.73 to 0.95, p=0.008). A higher Charlson Comorbidity Index and longer length of stay were associated with increased odds of readmission, while a higher Sequential Organ Failure Assessment score was associated with lower odds. Conclusion: This study highlights that social and clinical factors are associated with 30-day readmission in critically ill patients with heart failure. Consideration of social context alongside clinical risk may improve identification of patients at higher risk of rehospitalization.