In-Hospital Complications of Acute Decompensated Heart Failure Patients With Comorbid Rheumatoid Arthritis: A Retrospective Cohort Study.

Introduction Rheumatoid arthritis (RA) is associated with increased cardiovascular risk and chronic systemic inflammation, which may influence outcomes of heart failure (HF) hospitalization. However, the effect of RA on acute inpatient complications, bleeding risk, and mortality during HF admissions remains unclear. Methods We conducted a retrospective cohort study of adults hospitalized with HF across a large tertiary healthcare system from 2016 to 2024. The primary outcome was in-hospital mortality. Secondary outcomes included length of stay, gastrointestinal (GI) and major bleeding, pneumonia, respiratory failure, acute kidney injury (AKI), thromboembolism, and major adverse cardiac events (MACE). Multivariable logistic and negative binomial regression were used to assess associations after adjusting for demographics, comorbidities, laboratory values, and medications. Propensity score matching (PSM) minimized baseline confounding. Results The study included 81,366 HF patients. Those with RA were older, more often female, and had higher rates of chronic lung disease, systemic lupus erythematosus (SLE), and thrombocytopenia. After adjustment, RA was associated with higher odds of GI and major bleeding and longer hospital stays, but not with increased mortality or cardiovascular complications. Among those with RA, elevated C-reactive protein was associated with a higher risk of thromboembolic and cardiac complications. Pre-admission disease-modifying antirheumatic drug use was associated with lower thromboembolic risk, but higher risk of major adverse cardiac events. Conclusion RA was associated with a greater risk of bleeding complications and prolonged hospitalization during HF admissions but not increased in-hospital mortality. Elevated inflammatory markers and immunosuppressive therapy may contribute to thrombotic and cardiac complications and highlight the need for targeted monitoring strategies during hospitalization.