title: Optimal selection of asymptomatic patients for carotid endarterectomy based on predicted 5-year survival.
abstract: OBJECTIVE
  Although carotid endarterectomy (CEA) is performed to prevent stroke, long-term survival is essential to ensure benefit, especially in asymptomatic patients. We examined factors associated with 5-year survival following CEA in patients with asymptomatic internal carotid artery (ICA) stenosis.
  
  
  METHODS
  Prospectively collected data from 4114 isolated CEAs performed for asymptomatic stenosis across 24 centers in the Vascular Study Group of New England between 2003 and 2011 were used for this analysis. Late survival was determined with the Social Security Death Index. Cox proportional hazard models were used to identify risk factors for mortality within the first 5 years after CEA and to calculate a risk score for predicting 5-year survival.
  
  
  RESULTS
  Overall 3- and 5-year survival after CEA in asymptomatic patients were 90% (95% CI 89%-91%) and 82% (95% CI 81%-84%), respectively. By multivariate analysis, increasing age, diabetes, smoking history, congestive heart failure, chronic obstructive pulmonary disease, poor renal function (estimated glomerular filtration rate <60 or dialysis dependence), absence of statin use, and worse contralateral ICA stenosis were all associated with worse survival. Patients classified as low (27%), medium (68%), and high risk (5%) based on number of risk factors had 5-year survival rates of 96%, 80%, and 51%, respectively (P < .001).
  
  
  CONCLUSIONS
  More than four out of five asymptomatic patients selected for CEA in the Vascular Study Group of New England achieved 5-year survival, demonstrating that, overall, surgeons in our region selected appropriate patients for carotid revascularization. However, there were patients selected for surgery with high risk profiles, and our models suggest that the highest risk patients (such as those with multiple major risk factors including age ≥ 80, insulin-dependent diabetes, dialysis dependence, and severe contralateral ICA stenosis) are unlikely to survive long enough to realize a benefit of prophylactic CEA for asymptomatic stenosis. Predicting survival is important for decision making in these patients.
authors.affiliation: VA Outcomes Group, Dartmouth Hitchcock Medical Center, Lebanon, NH 03765, USA. jessica.wallaert@hitchcock.org
authors.forename: Jessica B
authors.initials: JB
authors.lastname: Wallaert
authors.forename: Jack L
authors.initials: JL
authors.lastname: Cronenwett
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Bertges
authors.forename: Andres
authors.initials: A
authors.lastname: Schanzer
authors.forename: Brian W
authors.initials: BW
authors.lastname: Nolan
authors.forename: Randall
authors.initials: R
authors.lastname: De Martino
authors.forename: Jens
authors.initials: J
authors.lastname: Eldrup-Jorgensen
authors.forename: Philip P
authors.initials: PP
authors.lastname: Goodney
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D058070:Asymptomatic Diseases; D002343:Carotid Artery, Internal / Q000601:surgery*; D016893:Carotid Stenosis / Q000175:diagnosis / Q000401:mortality / Q000601:surgery*; D003661:Decision Support Techniques; D016894:Endarterectomy, Carotid / Q000009:adverse effects / Q000401:mortality; D005260:Female; D006801:Humans; D008297:Male; D015999:Multivariate Analysis; D018579:Patient Selection; D016016:Proportional Hazards Models; D012042:Registries; D018570:Risk Assessment; D012307:Risk Factors; D012720:Severity of Illness Index; D013997:Time Factors; D016896:Treatment Outcome; D014481:United States