title: Impact of atrial fibrillation on mortality and readmission in older adults hospitalized with heart failure.
abstract: BACKGROUND
  Atrial fibrillation is common in older adults with heart failure. It is known to adversely affect outcomes.
  
  
  OBJECTIVE
  To examine the associations of atrial fibrillation with 4-year mortality and 30-day readmission in older adults hospitalized with heart failure.
  
  
  METHODS
  Patients were Medicare beneficiaries 65 years of age and older discharged with a primary diagnosis of heart failure. Baseline data were obtained by retrospective chart reviews and data on mortality and readmission were obtained from Medicare administrative files. Presence of atrial fibrillation was confirmed using electrocardiogram during hospital admission. Using Cox proportional hazards models we estimated bivariate and multivariable (adjusted for various patient and care covariates) hazards ratios (HR) and 95% confidence intervals (CI) for 4-year mortality and 30-day readmission of patients with atrial fibrillation compared with those without.
  
  
  RESULTS
  Patients (n=944) had a mean age (+/-S.D.) of 79 (+/-7) years, 61% were women, 18% African-Americans, 25% had atrial fibrillation by admission electrocardiogram, 64% died within 4 years, and 8% were readmitted. Patients with atrial fibrillation had a 52% increased risk of 4-year mortality (adjusted HR=1.52; 95%CI=1.11-2.07). Atrial fibrillation was also associated with higher risk of readmission (unadjusted HR=1.64; 95%CI=1.01-2.68). However, the association lost its statistical significance after adjustment for various patient and care variables (adjusted HR=2.09; 95%CI=0.94-4.65).
  
  
  CONCLUSIONS
  Presence of atrial fibrillation was associated with significant increased risk of long-term mortality in older adults hospitalized with heart failure and was associated with a non-significant higher risk of hospital readmission.
authors.affiliation: Division of Gerontology and Geriatric Medicine, Department of Medicine, School of Medicine, Center for Aging and Geriatric Heart Failure Clinic, University of Alabama at Birmingham, Birmingham, AL, USA. aahmed@uab.edu
authors.forename: Ali
authors.initials: A
authors.lastname: Ahmed
authors.forename: Phillip
authors.initials: P
authors.lastname: Thornton
authors.forename: Gilbert J
authors.initials: GJ
authors.lastname: Perry
authors.forename: Richard M
authors.initials: RM
authors.lastname: Allman
authors.forename: James F
authors.initials: JF
authors.lastname: DeLong
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000407:Alabama / Q000453:epidemiology; D001281:Atrial Fibrillation / Q000401:mortality* / Q000628:therapy*; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000401:mortality* / Q000628:therapy*; D006801:Humans; D008297:Male; D010351:Patient Discharge; D010359:Patient Readmission; D015203:Reproducibility of Results; D012307:Risk Factors; D013223:Statistics as Topic; D016019:Survival Analysis; D013997:Time Factors; D018487:Ventricular Dysfunction, Left / Q000401:mortality / Q000628:therapy