title: Significance of earlier carotid atherosclerosis for stroke subtypes.
abstract: OBJECTIVE
  In addition to advanced stenosis, earlier stages of carotid atherosclerosis are associated with the risk for stroke. However, the significance has not been established for specific stroke subtypes. This study examines the association of earlier carotid atherosclerosis with stroke subtypes.
  
  
  METHODS
  The subjects comprised 1059 patients (mean+/-SD age, 62+/-11 years) with <60% carotid stenosis. With the use of ultrasound, carotid atherosclerosis was evaluated by the plaque score, as defined by the sum of all plaque heights in bilateral carotid arteries. On the basis of neurological signs and symptoms, medical history, and brain MRI, we diagnosed stroke and its subtypes as follows: no stroke (n=738), atherothrombotic infarction (AI) (n=56), lacunar infarction (LI) (n=117), cardioembolic infarction (n=65), cerebral hemorrhage (n=26), and other or unclassified stroke (n=57).
  
  
  RESULTS
  The plaque score was higher in AI (10.5+/-5.9) and LI (6.0+/-5.1) groups than in the no-stroke group (4.3+/-4.9) (both P<0.05), although it was similar between other stroke groups and the no-stroke group. Each 1 SD greater plaque score was associated with 2.5-fold (95% CI, 2.0 to 3.2) higher risk for AI and 1.4-fold (95% CI, 1.2 to 1.7) higher risk for LI compared with the no-stroke group. When we adjusted for cardiovascular risk factors, plaque score remained significantly associated with AI but not with LI. By receiver operating characteristic curve analyses, the receiver operating characteristic area for AI (0.81 to 0.86) was greater than that for LI (0.62 to 0.67) when we used plaque score either alone or in combination with cardiovascular risk factors.
  
  
  CONCLUSIONS
  Although evaluation of carotid atherosclerosis may aid in the risk assessment for AI and LI, the benefit appears to be greater for AI.
authors.affiliation: Department of Internal Medicine and Therapeutics, Osaka University Graduate School of Medicine, Japan. nagaiy@medone.med.osaka-u.ac.jp
authors.forename: Y
authors.initials: Y
authors.lastname: Nagai
authors.forename: K
authors.initials: K
authors.lastname: Kitagawa
authors.forename: M
authors.initials: M
authors.lastname: Sakaguchi
authors.forename: Y
authors.initials: Y
authors.lastname: Shimizu
authors.forename: H
authors.initials: H
authors.lastname: Hashimoto
authors.forename: H
authors.initials: H
authors.lastname: Yamagami
authors.forename: M
authors.initials: M
authors.lastname: Narita
authors.forename: T
authors.initials: T
authors.lastname: Ohtsuki
authors.forename: M
authors.initials: M
authors.lastname: Hori
authors.forename: M
authors.initials: M
authors.lastname: Matsumoto
mesh_terms: D000368:Aged; D002339:Carotid Arteries / Q000000981:diagnostic imaging / Q000473:pathology; D002340:Carotid Artery Diseases / Q000175:diagnosis / Q000453:epidemiology*; D015984:Causality; D015897:Comorbidity; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012372:ROC Curve; D018570:Risk Assessment; D012307:Risk Factors; D012720:Severity of Illness Index; D020521:Stroke / Q000145:classification* / Q000453:epidemiology*; D014463:Ultrasonography