title: Carotid plaque surface irregularity predicts ischemic stroke: the northern Manhattan study.
abstract: OBJECTIVE
  There is scant population-based evidence regarding extracranial carotid plaque surface irregularity and ischemic stroke. Using a prospective cohort design, we evaluated the association of carotid plaque surface irregularity and the risk of ischemic stroke in a multiethnic population.
  
  
  METHODS
  High-resolution B-mode ultrasound of the carotid arteries was performed in 1939 stroke-free subjects (mean age 69+/-10.0 years; 59% women; 53% Hispanic, 25% black, 22% white). Plaque was defined as a focal protrusion 50% greater than the surrounding area and localized along the extracranial carotid tree (internal carotid artery/bifurcation vs common carotid artery). Plaque surface was categorized as regular or irregular. Cox proportional hazard models were used to assess the association of surface characteristics and the risk of ischemic stroke.
  
  
  RESULTS
  Among 1939 total subjects, carotid plaque was visualized in 56.3% (1 plaque: 21.6%, >1 plaque: 34.7%, irregular plaque: 5.5%). During a mean follow up of 6.2 years after ultrasound examination, 69 ischemic strokes occurred. Unadjusted cumulative 5-year risks of ischemic stroke were: 1.3%, 3.0%, and 8.5% for no plaque, regular plaque, and irregular plaque, respectively. After adjusting for demographics, traditional vascular risk factors, degree of stenosis, and plaque thickness, presence of irregular plaque (vs no plaque) was independently associated with ischemic stroke (Hazard ratio, 3.1; 95% CI, 1.1 to 8.5).
  
  
  CONCLUSIONS
  The presence of irregular carotid plaque independently predicted ischemic stroke in a multiethnic cohort. Plaque surface irregularities assessed by B-mode ultrasonography may help identify intermediate- to high-risk individuals beyond their vascular risk assessed by the presence of traditional risk factors.
authors.affiliation: The Neurological Institute, Columbia University, Stroke and Critical Care Division, 710 W 168th Street, Room 640, New York, NY 10032, USA.
authors.forename: Shyam
authors.initials: S
authors.lastname: Prabhakaran
authors.forename: Tatjana
authors.initials: T
authors.lastname: Rundek
authors.forename: Romel
authors.initials: R
authors.lastname: Ramas
authors.forename: Mitchell S V
authors.initials: MS
authors.lastname: Elkind
authors.forename: Myunghee Cho
authors.initials: MC
authors.lastname: Paik
authors.forename: Bernadette
authors.initials: B
authors.lastname: Boden-Albala
authors.forename: Ralph L
authors.initials: RL
authors.lastname: Sacco
mesh_terms: D000368:Aged; D016893:Carotid Stenosis / Q000453:epidemiology / Q000473:pathology*; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009519:New York City; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012307:Risk Factors; D020521:Stroke / Q000453:epidemiology / Q000473:pathology*