Outcomes of medicare beneficiaries with heart failure and atrial fibrillation.

OBJECTIVES This study sought to examine the long-term outcomes of patients hospitalized with heart failure and atrial fibrillation. BACKGROUND Atrial fibrillation is common among patients hospitalized with heart failure. Associations of pre-existing and new-onset atrial fibrillation with long-term outcomes are unclear. METHODS We analyzed 27,829 heart failure admissions between 2006 and 2008 at 281 hospitals in the American Heart Association's Get With The Guidelines-Heart Failure program linked with Medicare claims. Patients were classified as having pre-existing, new-onset, or no atrial fibrillation. Cox proportional hazards models were used to identify factors that were independently associated with all-cause mortality, all-cause readmission, and readmission for heart failure, stroke, and other cardiovascular disease at 1 and 3 years. RESULTS After multivariable adjustment, pre-existing atrial fibrillation was associated with greater 3-year risks of all-cause mortality (hazard ratio [HR]: 1.14 [99% confidence interval (CI): 1.08 to 1.20]), all-cause readmission (HR: 1.09 [99% CI: 1.05 to 1.14]), heart failure readmission (HR: 1.15 [99% CI: 1.08 to 1.21]), and stroke readmission (HR: 1.20 [99% CI: 1.01 to 1.41]), compared with no atrial fibrillation. There was also a greater hazard of mortality at 1 year among patients with new-onset atrial fibrillation (HR: 1.12 [99% CI: 1.01 to 1.24]). Compared with no atrial fibrillation, new-onset atrial fibrillation was not associated with a greater risk of the readmission outcomes. Stroke readmission rates at 1 year were just as high for patients with preserved ejection fraction as for patients with reduced ejection fraction. CONCLUSIONS Both pre-existing and new-onset atrial fibrillation were associated with greater long-term mortality among older patients with heart failure. Pre-existing atrial fibrillation was associated with greater risk of readmission.