title: Physical activity, obesity, weight change, and risk of atrial fibrillation: the Atherosclerosis Risk in Communities study.
abstract: BACKGROUND
  Physical activity (PA) has previously been suggested to attenuate the risk of atrial fibrillation (AF) conferred by excess body weight and weight gain. We prospectively examined the relationship between body size, weight change, and level of PA in a biracial cohort of middle-aged men and women.
  
  
  RESULTS
  Baseline characteristics on risk factor levels were obtained on 14 219 participants from the Atherosclerosis Risk in Communities Study. AF incidence was ascertained from 1987 to 2009. Adjusted Cox proportional hazards models were used to estimate the associations between body mass index, waist circumference, relative weight change, and PA level with incident AF. During follow-up, there were 1775 cases of incident AF. Body mass index and waist circumference were positively associated with AF as was weight loss/gain of >5% initial body weight. An ideal level of PA had a small protective effect on AF risk and partially attenuated the risk of AF associated with excess weight in men but not women: compared with men with a normal body mass index, the risk of AF in obese men with an ideal, intermediate, and poor level of PA at baseline was increased by 37%, 129%, and 156% (Pinteraction=0.04). During follow-up, PA did not modify the association between weight gain and risk of AF.
  
  
  CONCLUSIONS
  Obesity and extreme weight change are risk factors for incident AF, whereas being physically active is associated with a small reduction in risk. In men only, being physically active offset some, but not all, of the risk incurred with excess body weight.
authors.affiliation: From the School of Population Health, University of Queensland, Brisbane, Queensland, Australia (R.R.H.); Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis (J.R.M., A.A.); Johns Hopkins University, Baltimore, MD (S.K.A., L.R.L.); Department of Epidemiology and Prevention, Epidemiological Cardiology Research Center, Wake Forest University School of Medicine, Winston Salem, NC (E.Z.S.); and Cardiovascular Division, Department of Medicine, University of Minnesota Medical School, Minneapolis (L.Y.C.). r.huxley@uq.edu.au.
authors.forename: Rachel R
authors.initials: RR
authors.lastname: Huxley
authors.affiliation: From the School of Population Health, University of Queensland, Brisbane, Queensland, Australia (R.R.H.); Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis (J.R.M., A.A.); Johns Hopkins University, Baltimore, MD (S.K.A., L.R.L.); Department of Epidemiology and Prevention, Epidemiological Cardiology Research Center, Wake Forest University School of Medicine, Winston Salem, NC (E.Z.S.); and Cardiovascular Division, Department of Medicine, University of Minnesota Medical School, Minneapolis (L.Y.C.).
authors.forename: Jeffrey R
authors.initials: JR
authors.lastname: Misialek
authors.affiliation: From the School of Population Health, University of Queensland, Brisbane, Queensland, Australia (R.R.H.); Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis (J.R.M., A.A.); Johns Hopkins University, Baltimore, MD (S.K.A., L.R.L.); Department of Epidemiology and Prevention, Epidemiological Cardiology Research Center, Wake Forest University School of Medicine, Winston Salem, NC (E.Z.S.); and Cardiovascular Division, Department of Medicine, University of Minnesota Medical School, Minneapolis (L.Y.C.).
authors.forename: Sunil K
authors.initials: SK
authors.lastname: Agarwal
authors.affiliation: From the School of Population Health, University of Queensland, Brisbane, Queensland, Australia (R.R.H.); Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis (J.R.M., A.A.); Johns Hopkins University, Baltimore, MD (S.K.A., L.R.L.); Department of Epidemiology and Prevention, Epidemiological Cardiology Research Center, Wake Forest University School of Medicine, Winston Salem, NC (E.Z.S.); and Cardiovascular Division, Department of Medicine, University of Minnesota Medical School, Minneapolis (L.Y.C.).
authors.forename: Laura R
authors.initials: LR
authors.lastname: Loehr
authors.affiliation: From the School of Population Health, University of Queensland, Brisbane, Queensland, Australia (R.R.H.); Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis (J.R.M., A.A.); Johns Hopkins University, Baltimore, MD (S.K.A., L.R.L.); Department of Epidemiology and Prevention, Epidemiological Cardiology Research Center, Wake Forest University School of Medicine, Winston Salem, NC (E.Z.S.); and Cardiovascular Division, Department of Medicine, University of Minnesota Medical School, Minneapolis (L.Y.C.).
authors.forename: Elsayed Z
authors.initials: EZ
authors.lastname: Soliman
authors.affiliation: From the School of Population Health, University of Queensland, Brisbane, Queensland, Australia (R.R.H.); Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis (J.R.M., A.A.); Johns Hopkins University, Baltimore, MD (S.K.A., L.R.L.); Department of Epidemiology and Prevention, Epidemiological Cardiology Research Center, Wake Forest University School of Medicine, Winston Salem, NC (E.Z.S.); and Cardiovascular Division, Department of Medicine, University of Minnesota Medical School, Minneapolis (L.Y.C.).
authors.forename: Lin Y
authors.initials: LY
authors.lastname: Chen
authors.affiliation: From the School of Population Health, University of Queensland, Brisbane, Queensland, Australia (R.R.H.); Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis (J.R.M., A.A.); Johns Hopkins University, Baltimore, MD (S.K.A., L.R.L.); Department of Epidemiology and Prevention, Epidemiological Cardiology Research Center, Wake Forest University School of Medicine, Winston Salem, NC (E.Z.S.); and Cardiovascular Division, Department of Medicine, University of Minnesota Medical School, Minneapolis (L.Y.C.).
authors.forename: Alvaro
authors.initials: A
authors.lastname: Alonso
mesh_terms: D001281:Atrial Fibrillation / Q000175:diagnosis / Q000453:epidemiology* / Q000517:prevention & control; D015992:Body Mass Index; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009043:Motor Activity; D009765:Obesity / Q000175:diagnosis / Q000453:epidemiology* / Q000517:prevention & control; D011379:Prognosis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D012737:Sex Factors; D013997:Time Factors; D014481:United States / Q000453:epidemiology; D055105:Waist Circumference; D015430:Weight Gain / Q000208:ethnology; D015431:Weight Loss / Q000208:ethnology
keywords: atrial fibrillation; motor activity; obesity