title: Newly diagnosed atrial fibrillation linked to wake-up stroke and TIA: hypothetical implications.
abstract: BACKGROUND
  Based on the higher frequency of paroxysmal atrial fibrillation during night and early morning hours, we sought to analyze the association between newly diagnosed atrial fibrillation and wake-up ischemic cerebrovascular events.
  
  
  METHODS
  We prospectively assessed every acute ischemic stroke and TIA patient admitted to our hospital between 2008 and 2011. We used a forward step-by-step multiple logistic regression analysis to assess the relationship between newly diagnosed atrial fibrillation and wake-up ischemic stroke or TIA, after adjusting for significant covariates.
  
  
  RESULTS
  The study population comprised 356 patients, 274 (77.0%) with a diagnosis of acute ischemic stroke and 82 (23.0%) with TIA. A total of 41 (11.5%) of these events occurred during night sleep. A newly diagnosed atrial fibrillation was detected in 27 patients of 272 without known atrial fibrillation (9.9%). We found an independent association between newly diagnosed atrial fibrillation and wake-up ischemic stroke and TIA (odds ratio 3.6, 95% confidence interval 1.2-7.7, p = 0.019).
  
  
  CONCLUSIONS
  The odds of detecting a newly diagnosed atrial fibrillation were 3-fold higher among wake-up cerebrovascular events than among non-wake-up events. The significance of this independent association between newly diagnosed atrial fibrillation and wake-up ischemic stroke and TIA and the role of other comorbidities should be investigated in future studies.
authors.affiliation: Stroke Center at the Institute of Neurosciences, University Hospital, Favaloro Foundation, Buenos Aires, Argentina.
authors.forename: Patricia M
authors.initials: PM
authors.lastname: Riccio
authors.forename: Francisco R
authors.initials: FR
authors.lastname: Klein
authors.forename: Fátima
authors.initials: F
authors.lastname: Pagani Cassará
authors.forename: Francisco
authors.initials: F
authors.lastname: Muñoz Giacomelli
authors.forename: María E
authors.initials: ME
authors.lastname: González Toledo
authors.forename: Juan M
authors.initials: JM
authors.lastname: Racosta
authors.forename: Matías
authors.initials: M
authors.lastname: Delfitto
authors.forename: Eleanor S
authors.initials: ES
authors.lastname: Roberts
authors.forename: M Cecilia
authors.initials: MC
authors.lastname: Bahit
authors.forename: Luciano A
authors.initials: LA
authors.lastname: Sposato
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology; D005260:Female; D006801:Humans; D002546:Ischemic Attack, Transient / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012307:Risk Factors; D020521:Stroke / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology; D014851:Wakefulness / Q000502:physiology