title: Family history of atrial fibrillation is associated with earlier-onset and more symptomatic atrial fibrillation: Results from the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation (ORBIT-AF) registry.
abstract: BACKGROUND
  We addressed whether patients with a family history of atrial fibrillation (AF) were diagnosed as having AF earlier in life, were more symptomatic, and had worse outcomes compared with those without a family history of AF.
  
  
  METHODS
  Using the ORBIT-AF, we compared symptoms and disease characteristics in those with and without a family history of AF. A family history of AF was defined as AF in a first-degree family member and obtained by patient self-reporting. Multivariable Cox proportional hazard analyses were performed to compare the incidence of cardiovascular outcomes, AF progression, all-cause hospitalization, and all-cause death.
  
  
  RESULTS
  Among 9,999 patients with AF from 176 US outpatient clinics, 1,481 (14.8%) had a family history of AF. Relative to those without, those with a family history of AF developed AF 5 years earlier on average (median age 65 vs 70 years, P < .01), with less comorbidity, and had more severe AF-related symptoms. No differences were found between the 2 groups in the risk of AF progression (adjusted hazard ratio [HR] 0.98, 95% CI 0.85-1.14), stroke, non-central nervous system embolism, or transient ischemic attack (adjusted HR 0.95, 95% CI 0.67-1.34), all-cause hospitalization (adjusted HR 1.03, 95% CI 0.94-1.12), and all-cause death (adjusted HR 1.05, 95% CI 0.86-1.27).
  
  
  CONCLUSIONS
  Patients with a family history of AF developed AF at a younger age, had less comorbidity, and were more symptomatic. Once AF developed, no significantly increased risks of AF progression and thromboembolism were associated with a family history of AF compared with no family history.
authors.affiliation: Department of Cardiology, University Hospital of Gentofte, Hellerup, Denmark. Electronic address: annagundlund@gmail.com.
authors.forename: Anna
authors.initials: A
authors.lastname: Gundlund
authors.affiliation: Department of Cardiology, University Hospital of Copenhagen, Rigshospitalet, Denmark.
authors.forename: Emil Loldrup
authors.initials: EL
authors.lastname: Fosbøl
authors.affiliation: Duke Clinical Research Institute, Durham, NC.
authors.forename: Sunghee
authors.initials: S
authors.lastname: Kim
authors.affiliation: Ahmanson-UCLA Cardiomyopathy Center, Los Angeles, CA.
authors.forename: Gregg C
authors.initials: GC
authors.lastname: Fonarow
authors.affiliation: Mayo Clinic College of Medicine, Rochester, MN.
authors.forename: Bernard J
authors.initials: BJ
authors.lastname: Gersh
authors.affiliation: Boston University School of Medicine, Boston, MA.
authors.forename: Peter R
authors.initials: PR
authors.lastname: Kowey
authors.affiliation: Boston University School of Medicine, Boston, MA.
authors.forename: Elaine
authors.initials: E
authors.lastname: Hylek
authors.affiliation: Department of Medicine, Stanford University School of Medicine, Palo Alto, CA.
authors.forename: Kenneth W
authors.initials: KW
authors.lastname: Mahaffey
authors.affiliation: Duke Clinical Research Institute, Durham, NC.
authors.forename: Laine
authors.initials: L
authors.lastname: Thomas
authors.affiliation: Duke Clinical Research Institute, Durham, NC.
authors.forename: Jonathan P
authors.initials: JP
authors.lastname: Piccini
authors.affiliation: Duke Clinical Research Institute, Durham, NC.
authors.forename: Eric D
authors.initials: ED
authors.lastname: Peterson
mesh_terms: D017668:Age of Onset; D000368:Aged; D001281:Atrial Fibrillation / Q000150:complications / Q000175:diagnosis / Q000453:epidemiology / Q000628:therapy; D015897:Comorbidity; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D008487:Medical History Taking / Q000379:methods / Q000706:statistics & numerical data; D008875:Middle Aged; D010045:Outpatients / Q000706:statistics & numerical data; D016016:Proportional Hazards Models; D012042:Registries; D012307:Risk Factors; D063189:Symptom Assessment / Q000379:methods; D013923:Thromboembolism / Q000453:epidemiology / Q000209:etiology