title: Impact of carotid endarterectomy upon cognitive functioning. A systematic review of the literature.
abstract: OBJECTIVE
  The extent to which carotid endarterectomy (CEA) influences cognitive functioning has been the subject of a number of studies often with conflicting conclusions. This paper systematically reviews the literature in an attempt to clarify this issue.
  
  
  RESULTS
  Although the majority of studies (16/28) reported an improvement in cognition after surgery, a substantial minority (12/28) found no change. Studies before 1984 tended to report an improvement, while later studies tended to report no change in cognition. Cognitive improvement was also more likely the longer the time interval between CEA and assessment. The studies were found to differ on many methodological factors, e.g. sample size, type of patient and control group, severity and side of carotid stenosis, the range of cognitive tests and timing of postoperative assessment.
  
  
  CONCLUSIONS
  Given the conflicting findings, and the methodological issues, it is not possible to draw a clear conclusion regarding the impact of carotid endarterectomy upon cognition. Future research which pays attention to these methodological factors is needed in order to adequately resolve the current debate.
authors.affiliation: Department of Psychiatry and Behavioural Sciences, University College London Medical School, Middlesex Hospital, London, UK.
authors.forename: S
authors.initials: S
authors.lastname: Lunn
authors.forename: F
authors.initials: F
authors.lastname: Crawley
authors.forename: M J
authors.initials: MJ
authors.lastname: Harrison
authors.forename: M M
authors.initials: MM
authors.lastname: Brown
authors.forename: S P
authors.initials: SP
authors.lastname: Newman
mesh_terms: D002339:Carotid Arteries / Q000601:surgery*; D003071:Cognition / Q000502:physiology*; D004691:Endarterectomy; D006801:Humans; D011184:Postoperative Period