title: Does CHA2DS2-VASc improve stroke risk stratification in postmenopausal women with atrial fibrillation?
abstract: BACKGROUND
  Risk stratification of atrial fibrillation patients with a congestive heart failure (C), hypertension (H), age ≥ 75 (A), diabetes (D), stroke or transient ischemic attack (TIA) (S2) (CHADS2) score of <2 remains imprecise, particularly in women. Our objectives were to validate the CHADS2 and congestive heart failure (C), hypertension (H), age ≥ 75 (A2), diabetes (D), stroke, TIA or prior thromboembolic disease (S2)- vascular disease (V), age 65-74 (A), female gender (S) (CHA2DS2-VASc) stroke risk scores in a healthy cohort of American women with atrial fibrillation and to determine whether CHA2DS2-VASc further risk-stratifies individuals with a CHADS2 score of <2.
  
  
  METHODS
  We identified a cohort of 5981 women with atrial fibrillation not on warfarin at baseline (mean age 65.9 ± 7.2 years) enrolled in the Women's Health Initiative and followed for a median of 11.8 years. Univariate and multivariate proportional hazards analyses were used to examine these 2 risk scores, with main outcome measures being annualized event rates of ischemic stroke or transient ischemic attack stratified by risk score.
  
  
  RESULTS
  Annualized stroke/transient ischemic attack rates ranged from 0.36% to 2.43% with increasing CHADS2 score (0-4+) (hazard ratio [HR] 1.57; 95% confidence interval [CI], 1.45-1.71 for each 1-point increase) and 0.20%-2.02% with increasing CHA2DS2-VASc score (1-6+) (HR 1.50; 95% CI, 1.41-1.60 for each 1-point increase). CHA2DS2-VASc had a higher c statistic than CHADS2: 0.67 (95% CI, 0.65-0.69) versus 0.65 (95% CI, 0.62-0.67), P <.01. For CHADS2 scores <2, stroke risk almost doubled with every additional CHA2DS2-VASc point.
  
  
  CONCLUSIONS
  Although both CHADS2, and CHA2DS2-VASc are predictive of stroke risk in postmenopausal women with atrial fibrillation, CHA2DS2-VASc further risk-stratifies patients with a CHADS2 score <2.
authors.affiliation: Department of Cardiovascular Medicine, Cleveland Clinic, Cleveland, Ohio. Electronic address: abrahaj3@ccf.org.
authors.forename: Joellyn M
authors.initials: JM
authors.lastname: Abraham
authors.forename: Joseph
authors.initials: J
authors.lastname: Larson
authors.forename: Mina K
authors.initials: MK
authors.lastname: Chung
authors.forename: Anne B
authors.initials: AB
authors.lastname: Curtis
authors.forename: Kamakshi
authors.initials: K
authors.lastname: Lakshminarayan
authors.forename: Jonathan D
authors.initials: JD
authors.lastname: Newman
authors.forename: Marco
authors.initials: M
authors.lastname: Perez
authors.forename: Kathryn
authors.initials: K
authors.lastname: Rexrode
authors.forename: Nawar M
authors.initials: NM
authors.lastname: Shara
authors.forename: Allen J
authors.initials: AJ
authors.lastname: Solomon
authors.forename: Marcia L
authors.initials: ML
authors.lastname: Stefanick
authors.forename: James C
authors.initials: JC
authors.lastname: Torner
authors.forename: Bruce L
authors.initials: BL
authors.lastname: Wilkoff
authors.forename: Sylvia
authors.initials: S
authors.lastname: Wassertheil-Smoller
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000150:complications*; D002318:Cardiovascular Diseases / Q000150:complications; D015331:Cohort Studies; D048909:Diabetes Complications / Q000150:complications; D005260:Female; D006333:Heart Failure / Q000150:complications; D006801:Humans; D008875:Middle Aged; D015999:Multivariate Analysis; D017698:Postmenopause; D016016:Proportional Hazards Models; D012107:Research Design; D012307:Risk Factors; D020521:Stroke / Q000209:etiology*; D016387:Women's Health
keywords: Atrial fibrillation; CHA(2)DS(2)-VASc; CHADS(2); Stroke; Women