Association of systemic lupus erythematosus with 90-day readmission following heart failure hospitalization: A national readmission database (NRD) analysis, 2016–2017

Background Systemic lupus erythematosus is a chronic autoimmune disease associated with heightened cardiovascular risk. Data on the impact of systemic lupus erythematosus on outcomes following heart failure hospitalization remain limited. This study aimed to evaluate whether systemic lupus erythematosus is independently associated with 90-days readmission and other clinical outcomes among patients hospitalized with heart failure. Methods We conducted a retrospective cohort study using the 2016–2017 Nationwide Readmissions Database to evaluate the association of systemic lupus erythematosus with 90-days readmission after heart failure hospitalization. Adults ≥18 years with an index admission for heart failure were included. The primary outcome was 90-days all-cause readmission. Secondary outcomes included in-hospital mortality, median length of stay, and hospitalization costs. Multivariable Cox proportional hazards were used to identify independent predictors of outcomes. Results Among 1,625,731 patients hospitalized with heart failure, 9096 had comorbid systemic lupus erythematosus. Compared with non-systemic lupus erythematosus patients, those with systemic lupus erythematosus were younger (mean age 61 vs 72 years), predominantly female, and more likely to have socioeconomic disadvantage and a higher comorbidity burden. The 90-days readmission rate was significantly higher in the systemic lupus erythematosus cohort (41%) versus the non-systemic lupus erythematosus cohort (34%) (HR: 1.07; 95% CI: 1.02–1.12; p = 0.010). In-hospital mortality did not differ significantly between groups; however, mortality during readmissions was nearly doubled compared with index admissions (5.4% vs 2.9%). SLE patients had a median length of stay of 4 days (vs 4 days in non-SLE) and incurred median hospitalization costs of USD 32,872 (13% higher than non-SLE patients). Independent predictors of readmission included Medicaid insurance, weekend admission, renal failure, myocardial infarction, and discharge to a non-home setting, whereas female sex, treatment at metropolitan teaching hospitals, and comorbid hypertension or diabetes were associated with a lower risk of readmission. Conclusion Systemic lupus erythematosus is independently associated with an increased risk of 90-days readmission following heart failure hospitalization, contributing to greater healthcare utilization and costs. These findings highlight the need for tailored strategies for transitional care, multidisciplinary follow-up, and socioeconomic support.