title: Lean body mass and risk of incident atrial fibrillation in post-menopausal women.
abstract: High body mass index (BMI) is a risk factor for atrial fibrillation (AF). The aim of this study was to determine whether lean body mass (LBM) predicts AF.
  
  
  
  The Women's Health Initiative is a study of post-menopausal women aged 50-79 enrolled at 40 US centres from 1994 to 1998. A subset of 11 393 participants at three centres underwent dual-energy X-ray absorptiometry. Baseline demographics and clinical histories were recorded. Incident AF was identified using hospitalization records and diagnostic codes from Medicare claims. A multivariable Cox hazard regression model adjusted for demographic and clinical risk factors was used to evaluate associations between components of body composition and AF risk. After exclusion for prevalent AF or incomplete data, 8832 participants with an average age of 63.3 years remained for analysis. Over the 11.6 years of average follow-up time, 1035 women developed incident AF. After covariate adjustment, all measures of LBM were independently associated with higher rates of AF: total LBM [hazard ratio (HR) 1.24 per 5 kg increase, 95% confidence intervals (CI) 1.14-1.34], central LBM (HR 1.51 per 5 kg increase, 95% CI 1.31-1.74), and peripheral LBM (HR 1.39 per 5 kg increase, 95% CI 1.19-1.63). The association between total LBM and AF remained significant after adjustment for total fat mass (HR 1.22 per 5 kg increase, 95% CI 1.13-1.31).
  
  
  
  Greater LBM is a strong independent risk factor for AF. After adjusting for obesity-related risk factors, the risk of AF conferred by higher BMI is primarily driven by the association between LBM and AF.
authors.affiliation: Division of Cardiovascular Medicine, Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA.
authors.forename: Farnaz
authors.initials: F
authors.lastname: Azarbal
authors.affiliation: Department of Medicine, Stanford Prevention Research Center, Stanford University School of Medicine, Stanford, CA, USA.
authors.forename: Marcia L
authors.initials: ML
authors.lastname: Stefanick
authors.affiliation: Division of Cardiovascular Medicine, Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA.
authors.forename: Themistocles L
authors.initials: TL
authors.lastname: Assimes
authors.affiliation: Division of Preventive Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: JoAnn E
authors.initials: JE
authors.lastname: Manson
authors.affiliation: Department of Medicine, University of Arizona, Tucson, AZ, USA.
authors.forename: Jennifer W
authors.initials: JW
authors.lastname: Bea
authors.affiliation: Division of Preventive and Behavioral Medicine, University of Massachusetts Medical School, Worcester, MA, USA.
authors.forename: Wenjun
authors.initials: W
authors.lastname: Li
authors.affiliation: Division of Cardiovascular Medicine, Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA Department of Health Research and Policy, Stanford University School of Medicine, Stanford, CA, USA.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Hlatky
authors.affiliation: Data Coordinating Center, Fred Hutchinson Cancer Research Center, Seattle, WA, USA.
authors.forename: Joseph C
authors.initials: JC
authors.lastname: Larson
authors.affiliation: Center for Health Research, Kaiser Permanente Northwest, Portland, OR, USA.
authors.forename: Erin S
authors.initials: ES
authors.lastname: LeBlanc
authors.affiliation: Division of Preventive Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA Department of Medicine, Division of Cardiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Christine M
authors.initials: CM
authors.lastname: Albert
authors.affiliation: Department of Biochemistry and Molecular Medicine, University of California Davis, Davis, CA, USA.
authors.forename: Rami
authors.initials: R
authors.lastname: Nassir
authors.affiliation: School of Medicine and Health Sciences, George Washington University, Washington, DC, USA.
authors.forename: Lisa W
authors.initials: LW
authors.lastname: Martin
authors.affiliation: Division of Cardiovascular Medicine, Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA Stanford Center for Inherited Cardiovascular Disease, 300 Pasteur Drive #H2155, Stanford, CA 94305, USA mvperez@stanford.edu.
authors.forename: Marco V
authors.initials: MV
authors.lastname: Perez
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation; D001823:Body Composition; D015992:Body Mass Index; D005260:Female; D006801:Humans; D015994:Incidence; D008875:Middle Aged; D009765:Obesity; D017698:Postmenopause; D012307:Risk Factors
keywords: Arrhythmia; Atrial fibrillation; Epidemiology