title: 50 year trends in atrial fibrillation prevalence, incidence, risk factors, and mortality in the Framingham Heart Study: a cohort study.
abstract: BACKGROUND
  Comprehensive long-term data on atrial fibrillation trends in men and women are scant. We aimed to provide such data through analysis of the Framingham cohort over 50 years.
  
  
  METHODS
  We investigated trends in incidence, prevalence, and risk factors for atrial fibrillation and its association with stroke and mortality after onset in 9511 participants enrolled in the Framingham Heart Study between 1958 and 2007. We analysed trends within 10 year groups (1958-67, 1968-77, 1978-87, 1988-97, and 1998-2007), stratified by sex.
  
  
  RESULTS
  During 50 years of observation (202,417 person-years), 1544 cases of new-onset atrial fibrillation occurred (of whom 723 [47%] were women). Between 1958-67 and 1998-2007, age-adjusted prevalence of atrial fibrillation quadrupled from 20·4 to 96·2 cases per 1000 person-years in men and from 13·7 to 49·4 cases per 1000 person-years in women; age-adjusted incidence increased from 3·7 to 13·4 new cases per 1000 person-years in men and from 2·5 to 8·6 new cases per 1000 person-years in women (ptrend<0·0001 for all comparisons). For atrial fibrillation diagnosed by electrocardiograph (ECG) during routine Framingham examinations, age-adjusted prevalence per 1000 person-years increased (12·6 in 1958-67 to 25·7 in 1998-2007 in men, ptrend=0·0007; 8·1 to 11·8 in women, ptrend=0·009). However, age-adjusted incidence of atrial fibrillation by Framingham Heart Study ECGs did not change significantly with time. Although the prevalence of most risk factors changed over time, their associated hazards for atrial fibrillation changed little. Multivariable-adjusted proportional hazards models revealed a 74% (95% CI 50-86%) decrease in stroke (hazards ratio [HR] 3·77, 95% CI 1·98-7·20 in 1958-1967 compared with 1998-2007; ptrend=0·0001) and a 25% (95% CI -3-46%) decrease in mortality (HR 1·34, 95% CI 0·97-1·86 in 1958-1967 compared with 1998-2007; ptrend=0·003) in 20 years following atrial fibrillation onset.
  
  
  CONCLUSIONS
  Trends of increased incidence and prevalence of atrial fibrillation in the community were probably partly due to enhanced surveillance. Measures are needed to enhance early detection of atrial fibrillation, through increased awareness coupled with targeted screening programmes and risk factor-specific prevention.
  
  
  BACKGROUND
  NIH, NHLBI, NINDS, Deutsche Forschungsgemeinschaft.
authors.affiliation: National Heart, Lung, and Blood Institute's Framingham Study, Framingham, MA, USA; Deutsches Zentrum fuer Herz-Kreislauf-Forschung, University Heart Center, Department of General and Interventional Cardiology, Hamburg, Germany. Electronic address: r.schnabel@uke.de.
authors.forename: Renate B
authors.initials: RB
authors.lastname: Schnabel
authors.affiliation: National Heart, Lung, and Blood Institute's Framingham Study, Framingham, MA, USA; Department of Biostatistics, Boston University School of Public Health, Boston, MA, USA.
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Yin
authors.affiliation: National Heart, Lung, and Blood Institute's Framingham Study, Framingham, MA, USA; Division of Biostatistics and Health Services Research, Department of Quantitative Health Sciences, University of Massachusetts Medical School, Boston, MA, USA.
authors.forename: Philimon
authors.initials: P
authors.lastname: Gona
authors.affiliation: National Heart, Lung, and Blood Institute's Framingham Study, Framingham, MA, USA; Department of Biostatistics, Boston University School of Public Health, Boston, MA, USA; Department of Mathematics and Statistics, Boston University, Boston, MA, USA.
authors.forename: Martin G
authors.initials: MG
authors.lastname: Larson
authors.affiliation: National Heart, Lung, and Blood Institute's Framingham Study, Framingham, MA, USA; Department of Biostatistics, Boston University School of Public Health, Boston, MA, USA; Neurology Department, School of Medicine, Boston University, Boston, MA, USA.
authors.forename: Alexa S
authors.initials: AS
authors.lastname: Beiser
authors.affiliation: Cardiology Division, Department of Medicine, University of Massachusetts Medical School, Boston, MA, USA.
authors.forename: David D
authors.initials: DD
authors.lastname: McManus
authors.affiliation: National Heart, Lung, and Blood Institute's Framingham Study, Framingham, MA, USA; Cardiovascular Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Center for Human Genetic Research, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Cardiology Division, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Program in Medical Population Genetics, Broad Institute of Harvard and Massachusetts Institute of Technology, Cambridge, MA, USA.
authors.forename: Christopher
authors.initials: C
authors.lastname: Newton-Cheh
authors.affiliation: Cardiology Division, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Steven A
authors.initials: SA
authors.lastname: Lubitz
authors.affiliation: Cardiology Section, School of Medicine, Boston University, Boston, MA, USA.
authors.forename: Jared W
authors.initials: JW
authors.lastname: Magnani
authors.affiliation: Cardiovascular Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Cardiology Division, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Program in Medical Population Genetics, Broad Institute of Harvard and Massachusetts Institute of Technology, Cambridge, MA, USA.
authors.forename: Patrick T
authors.initials: PT
authors.lastname: Ellinor
authors.affiliation: National Heart, Lung, and Blood Institute's Framingham Study, Framingham, MA, USA.
authors.forename: Sudha
authors.initials: S
authors.lastname: Seshadri
authors.affiliation: National Heart, Lung, and Blood Institute's Framingham Study, Framingham, MA, USA; Neurology Department, School of Medicine, Boston University, Boston, MA, USA; Preventive Medicine Section, School of Medicine, Boston University, Boston, MA, USA.
authors.forename: Philip A
authors.initials: PA
authors.lastname: Wolf
authors.affiliation: National Heart, Lung, and Blood Institute's Framingham Study, Framingham, MA, USA; Whitaker Cardiovascular Institute, School of Medicine, Boston University, Boston, MA, USA; Evans Memorial Medicine Department, School of Medicine, Boston University, Boston, MA, USA; Cardiology Section, School of Medicine, Boston University, Boston, MA, USA; Preventive Medicine Section, School of Medicine, Boston University, Boston, MA, USA.
authors.forename: Ramachandran S
authors.initials: RS
authors.lastname: Vasan
authors.affiliation: National Heart, Lung, and Blood Institute's Framingham Study, Framingham, MA, USA; Department of Epidemiology, Boston University School of Public Health, Boston, MA, USA; Whitaker Cardiovascular Institute, School of Medicine, Boston University, Boston, MA, USA; Evans Memorial Medicine Department, School of Medicine, Boston University, Boston, MA, USA; Cardiology Section, School of Medicine, Boston University, Boston, MA, USA; Preventive Medicine Section, School of Medicine, Boston University, Boston, MA, USA.
authors.forename: Emelia J
authors.initials: EJ
authors.lastname: Benjamin
authors.affiliation: National Heart, Lung, and Blood Institute's Framingham Study, Framingham, MA, USA; Preventive Medicine Section, School of Medicine, Boston University, Boston, MA, USA; Population Sciences Branch, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA.
authors.forename: Daniel
authors.initials: D
authors.lastname: Levy
mesh_terms: D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000453:epidemiology* / Q000209:etiology; D015331:Cohort Studies; D004562:Electrocardiography; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009026:Mortality / Q000639:trends; D015995:Prevalence; D012307:Risk Factors; D017678:Sex Distribution; D020521:Stroke / Q000453:epidemiology / Q000209:etiology; D014481:United States / Q000453:epidemiology