title: Mitral annular calcification and incident atrial fibrillation in the Multi-Ethnic Study of Atherosclerosis.
abstract: OBJECTIVE
  The associations of mitral annular calcification (MAC) with atrial fibrillation (AF) risk factors and related outcomes suggest a possible association between MAC and AF. The aim of this study was to examine the association between MAC and AF in a racially and ethnically diverse population.
  
  
  RESULTS
  This analysis included 6641 participants (mean age 62 ± 10 years; 53% women; 27% Blacks; 22% Hispanics; 12% Chinese-Americans) from the Multi-Ethnic Study of Atherosclerosis (MESA) who were free of clinical cardiovascular disease and AF at baseline. The presence of MAC was defined by cardiac computed tomography (CT) as an Agatston score >0. Atrial fibrillation was ascertained by hospital discharge records and from Medicare claims data until 31 December 2010. Cox regression was used to compute hazard ratios (HRs) and 95% confidence intervals (95% CIs) for the association between MAC and AF. At baseline, 619 (9.3%) participants had MAC. Over a median follow-up of 8.5 years, 308 (4.6%) participants developed AF. In a multivariable adjusted model, MAC was associated with an increased risk of AF (HR = 1.9, 95% CI = 1.5, 2.5). This association was consistent across subgroups of age, sex, race/ethnicity (Whites vs. non-Whites), hypertension, diabetes, and left atrial enlargement. The addition of MAC to the Framingham Heart Study and CHARGE AF risk scores for AF improved the C-statistics from 0.769 to 0.776 (P = 0.038) and 0.788 to 0.792 (P = 0.089), respectively.
  
  
  CONCLUSIONS
  The presence of MAC was predictive of incident AF in MESA. Potentially, these findings suggest a usefulness of cardiac CT to identify individuals at risk for AF.
authors.affiliation: Department of Internal Medicine, Wake Forest School of Medicine, Winston-Salem, NC, USA woneal@wakehealth.edu.
authors.forename: Wesley T
authors.initials: WT
authors.lastname: O'Neal
authors.affiliation: Department of Cardiovascular Sciences, East Carolina Heart Institute, Brody School of Medicine, East Carolina University, Greenville, NC, USA.
authors.forename: Jimmy T
authors.initials: JT
authors.lastname: Efird
authors.affiliation: Departments of Medicine and Cardiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Saman
authors.initials: S
authors.lastname: Nazarian
authors.affiliation: Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis, MN, USA.
authors.forename: Alvaro
authors.initials: A
authors.lastname: Alonso
authors.affiliation: Cardiovascular Health Research Unit and Department of Epidemiology, University of Washington, and Group Health Research Institute, Seattle, WA, USA.
authors.forename: Susan R
authors.initials: SR
authors.lastname: Heckbert
authors.affiliation: Epidemiological Cardiology Research Center (EPICARE), Department of Epidemiology and Prevention, and Department of Internal Medicine, Section on Cardiology, Wake Forest School of Medicine, Winston-Salem, NC, USA.
authors.forename: Elsayed Z
authors.initials: EZ
authors.lastname: Soliman
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000453:epidemiology*; D002114:Calcinosis / Q000000981:diagnostic imaging / Q000453:epidemiology*; D015331:Cohort Studies; D003920:Diabetes Mellitus / Q000453:epidemiology; D005006:Ethnicity / Q000706:statistics & numerical data; D005260:Female; D006349:Heart Valve Diseases / Q000000981:diagnostic imaging / Q000453:epidemiology*; D006801:Humans; D006973:Hypertension / Q000453:epidemiology; D015994:Incidence; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000000981:diagnostic imaging*; D061330:Multidetector Computed Tomography; D015999:Multivariate Analysis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D014057:Tomography, X-Ray Computed; D014481:United States / Q000453:epidemiology
keywords: Atrial fibrillation; Epidemiology; Mitral annulus calcification