title: Carotid artery stenting compared with endarterectomy in patients with symptomatic carotid stenosis (International Carotid Stenting Study): a randomised controlled trial with cost-effectiveness analysis.
abstract: BACKGROUND
  Carotid artery stenting (CAS) is an alternative to carotid endarterectomy (CEA) for the treatment of carotid stenosis, but safety and long-term efficacy were uncertain.
  
  
  OBJECTIVE
  To compare the risks, benefits and cost-effectiveness of CAS versus CEA for symptomatic carotid stenosis.
  
  
  METHODS
  International, multicentre, randomised controlled, open, prospective clinical trial.
  
  
  METHODS
  Hospitals at 50 centres worldwide.
  
  
  METHODS
  Patients older than 40 years of age with symptomatic atheromatous carotid artery stenosis.
  
  
  METHODS
  Patients were randomly allocated stenting or endarterectomy using a computerised service and followed for up to 10 years.
  
  
  METHODS
  The primary outcome measure was the long-term rate of fatal or disabling stroke, analysed by intention to treat (ITT). Disability was assessed using the modified Rankin Scale (mRS). A cost-utility analysis estimating mean costs and quality-adjusted life-years (QALYs) was calculated over a 5-year time horizon.
  
  
  RESULTS
  A total of 1713 patients were randomised but three withdrew consent immediately, leaving 1710 for ITT analysis (853 were assigned to stenting and 857 were assigned to endarterectomy). The incidence of stroke, death or procedural myocardial infarction (MI) within 120 days of treatment was 8.5% in the CAS group versus 5.2% in the CEA group (72 vs. 44 events) [hazard ratio (HR) 1.69, 95% confidence interval (CI) 1.16 to 2.45; p = 0.006]. In the analysis restricted to patients who completed stenting, age independently predicted the risk of stroke, death or MI within 30 days of CAS (relative risk increase 1.17% per 5 years of age, 95% CI 1.01% to 1.37%). Use of an open-cell stent conferred higher risk than a closed-cell stent (relative risk 1.92, 95% CI 1.11 to 3.33), but use of a cerebral protection device did not modify the risk. CAS was associated with a higher risk of stroke in patients with an age-related white-matter changes score of 7 or more (HR 2.98, 95% CI 1.29 to 6.93; p = 0.011). After completion of follow-up with a median of 4.2 years, the number of patients with fatal or disabling stroke in the CAS and CEA groups (52 vs. 49), and the cumulative 5-year risk did not differ significantly (6.4% vs. 6.5%) (HR 1.06, 95% CI 0.72 to 1.57; p = 0.776). Stroke of any severity was more frequent in the CAS group (15.2% vs. 9.4% in the CEA group) (HR 1.712, 95% CI 1.280 to 2.300; p < 0.001). There was no significant difference in long-term rates of severe carotid restenosis or occlusion (10.8% in the CAS group vs. 8.6% in the CEA group) (HR 1.25, 95% CI 0.89 to 1.75; p = 0.20). There was no difference in the distribution of mRS scores at 1-year, 5-year or final follow-up. There were no differences in costs or QALYs between the treatments.
  
  
  CONCLUSIONS
  Patients and investigators were not blinded to treatment allocation. Interventionists' experience of stenting was less than that of surgeons with endarterectomy. Data on costs of managing strokes were not collected.
  
  
  CONCLUSIONS
  The functional outcome after stenting is similar to endarterectomy, but stenting is associated with a small increase in the risk of non-disabling stroke. The choice between stenting and endarterectomy should take into account the procedural risks related to individual patient characteristics. Future studies should include measurement of cognitive function, assessment of carotid plaque morphology and identification of clinical characteristics that determine benefit from revascularisation.
  
  
  BACKGROUND
  Current Controlled Trials ISRCTN25337470.
  
  
  BACKGROUND
  This project was funded by the National Institute for Health Research Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 20, No. 20. See the NIHR Journal Library website for further project information. Further funding was provided by the Medical Research Council, Stroke Association, Sanofi-Synthélabo and the European Union.
authors.affiliation: Department of Brain Repair and Rehabilitation, UCL Institute of Neurology, University College London, London, UK.
authors.forename: Roland L
authors.initials: RL
authors.lastname: Featherstone
authors.affiliation: Department of Medical Statistics Unit, Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, UK.
authors.forename: Joanna
authors.initials: J
authors.lastname: Dobson
authors.affiliation: Department of Brain Repair and Rehabilitation, UCL Institute of Neurology, University College London, London, UK.
authors.forename: Jörg
authors.initials: J
authors.lastname: Ederle
authors.affiliation: Department of Brain Repair and Rehabilitation, UCL Institute of Neurology, University College London, London, UK.
authors.forename: David
authors.initials: D
authors.lastname: Doig
authors.affiliation: Department of Brain Repair and Rehabilitation, UCL Institute of Neurology, University College London, London, UK.|Department of Neurology and Stroke Centre, University Hospital Basel, Basel University, Basel, Switzerland.
authors.forename: Leo H
authors.initials: LH
authors.lastname: Bonati
authors.affiliation: Department of Applied Health Research, University College London, London, UK.
authors.forename: Stephen
authors.initials: S
authors.lastname: Morris
authors.affiliation: Department of Applied Health Research, University College London, London, UK.
authors.forename: Nishma V
authors.initials: NV
authors.lastname: Patel
authors.affiliation: Department of Brain Repair and Rehabilitation, UCL Institute of Neurology, University College London, London, UK.
authors.forename: Martin M
authors.initials: MM
authors.lastname: Brown
mesh_terms: D000368:Aged; D002339:Carotid Arteries / Q000601:surgery; D016893:Carotid Stenosis / Q000401:mortality / Q000601:surgery / Q000628:therapy*; D003362:Cost-Benefit Analysis; D016894:Endarterectomy, Carotid; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012307:Risk Factors; D015607:Stents; D020521:Stroke / Q000209:etiology / Q000401:mortality / Q000517:prevention & control; D013997:Time Factors; D016896:Treatment Outcome