title: Atrial fibrillation in stroke-free patients is associated with memory impairment and hippocampal atrophy.
abstract: OBJECTIVE
  To determine whether atrial fibrillation (AF) in stroke-free patients is associated with impaired cognition and structural abnormalities of the brain. AF contributes to stroke and secondary cognitive decline. In the absence of manifest stroke, AF can activate coagulation and cause cerebral microembolism which could damage the brain.
  
  
  RESULTS
  We cross-sectionally evaluated 122 stroke-free individuals with AF recruited locally within the German Competence Network on AF. As comparator, we recruited 563 individuals aged 37-84 years without AF from the same community. Subjects underwent 3 T magnetic resonance imaging to assess covert territorial brain infarction, white matter lesions, and brain volume measures. Subjects with evidence for stroke, dementia, or depression were excluded. Cognitive function was assessed by an extensive neuropsychological test battery covering the domains learning and memory, attention and executive functions, working memory, and visuospatial skills. Cognitive scores and radiographic measures were compared across individuals with and without AF by stepwise multiple regression models. Stroke-free individuals with AF performed significantly worse in tasks of learning and memory (ß = -0.115, P < 0.01) as well as attention and executive functions (ß = -0.105, P < 0.01) compared with subjects without AF. There was also a trend (P = 0.062) towards worse performance in learning and memory tasks in patients with chronic as compared with paroxysmal AF. Corresponding to the memory impairment, hippocampal volume was reduced in patients with AF. Other radiographic measures did not differ between groups.
  
  
  CONCLUSIONS
  Even in the absence of manifest stroke, AF is a risk factor for cognitive impairment and hippocampal atrophy. Therefore, cognition and measures of structural brain integrity should be considered in the evaluation of novel treatments for AF.
authors.affiliation: Department of Neurology, University of Münster, A. Schweitzer Street 33, 48129 Münster, Germany. knecht@uni-muenster.de
authors.forename: Stefan
authors.initials: S
authors.lastname: Knecht
authors.forename: Christian
authors.initials: C
authors.lastname: Oelschläger
authors.forename: Thomas
authors.initials: T
authors.lastname: Duning
authors.forename: Hubertus
authors.initials: H
authors.lastname: Lohmann
authors.forename: Johannes
authors.initials: J
authors.lastname: Albers
authors.forename: Christoph
authors.initials: C
authors.lastname: Stehling
authors.forename: Walter
authors.initials: W
authors.lastname: Heindel
authors.forename: Günter
authors.initials: G
authors.lastname: Breithardt
authors.forename: Klaus
authors.initials: K
authors.lastname: Berger
authors.forename: E Bernd
authors.initials: EB
authors.lastname: Ringelstein
authors.forename: Paulus
authors.initials: P
authors.lastname: Kirchhof
authors.forename: Heike
authors.initials: H
authors.lastname: Wersching
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000473:pathology / Q000523:psychology*; D001284:Atrophy / Q000523:psychology; D003430:Cross-Sectional Studies; D005260:Female; D006624:Hippocampus / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008569:Memory Disorders / Q000209:etiology* / Q000473:pathology; D008875:Middle Aged; D020521:Stroke / Q000473:pathology / Q000523:psychology*