title: Prevention of functional impairment by endarterectomy for symptomatic high-grade carotid stenosis. North American Symptomatic Carotid Endarterectomy Trial Collaborators.
abstract: OBJECTIVE
  To determine whether carotid endarterectomy prevents deterioration of functional status among patients with transient ischemic attacks or nondisabling strokes and ipsilateral carotid stenosis of 70% to 99%.
  
  
  METHODS
  Multicentered randomized controlled trial with an average 18-month follow-up.
  
  
  METHODS
  Fifty clinical centers in North America.
  
  
  METHODS
  A total of 659 patients presenting with recent transient attacks of nondisabling stroke and ipsilateral atherosclerotic carotid stenosis of 70% to 99% were included. Patients were stable neurologically at the time of entry. No patient was lost to follow-up.
  
  
  METHODS
  Vascular surgeons and neurosurgeons were prescreened for low perioperative complication rates. Patients were randomly allocated to carotid endarterectomy plus continuing medical care (n = 328) or medical care alone (n = 331), including antiplatelet therapy.
  
  
  METHODS
  All patients were assessed by neurologists for the occurrence of stroke and functional status at scheduled intervals after entry.
  
  
  RESULTS
  In addition to a previously reported risk reduction for ipsilateral stroke for patients assigned to carotid endarterectomy, there was an absolute risk reduction (and relative risk reduction [RRR]) for functional status impairment of 5.6% (RRR, 69%) for vision, 4.6% (RRR, 87%) for comprehension of language, 8.3% (RRR, 88%) for fluency of speech, 4.3% (RRR, 84%) for swallowing, 6.0% (RRR, 53%) for lower-limb function, 9.3% (RRR, 75%) for upper-limb function, 7.4% (RRR, 60%) for shopping, and 10.5% (RRR, 50%) for visiting outside usual residence (P < .05, two-tailed, for all items).
  
  
  CONCLUSIONS
  Carotid endarterectomy reduced the risk for impairment of function among patients with recent symptomatic cerebral ischemia and ipsilateral high-grade carotid stenosis.
authors.affiliation: Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada.
authors.forename: R B
authors.initials: RB
authors.lastname: Haynes
authors.forename: D W
authors.initials: DW
authors.lastname: Taylor
authors.forename: D L
authors.initials: DL
authors.lastname: Sackett
authors.forename: K
authors.initials: K
authors.lastname: Thorpe
authors.forename: G G
authors.initials: GG
authors.lastname: Ferguson
authors.forename: H J
authors.initials: HJ
authors.lastname: Barnett
mesh_terms: D002343:Carotid Artery, Internal; D016893:Carotid Stenosis / Q000503:physiopathology / Q000601:surgery* / Q000628:therapy; D002561:Cerebrovascular Disorders / Q000209:etiology / Q000517:prevention & control*; D004691:Endarterectomy; D006801:Humans; D002546:Ischemic Attack, Transient / Q000209:etiology / Q000517:prevention & control*; D009460:Neurologic Examination; D012044:Regression Analysis; D016896:Treatment Outcome