title: Apolipoprotein E genotype and the risk of recurrent lobar intracerebral hemorrhage.
abstract: BACKGROUND
  Recurrent lobar intracerebral hemorrhage is the hallmark of cerebral amyloid angiopathy. The factors that predispose patients to early recurrence of lobar hemorrhage are unknown. One candidate is the apolipoprotein E gene, since both the epsilon2 and the epsilon4 alleles of apolipoprotein E appear to be associated with the severity of amyloid angiopathy.
  
  
  METHODS
  We performed a prospective, longitudinal study of consecutive elderly patients who survived a lobar intracerebral hemorrhage. The patients were followed for recurrent hemorrhagic stroke by interviews at six-month intervals and reviews of medical records and computed tomographic scans.
  
  
  RESULTS
  Nineteen of 71 enrolled patients had recurrent hemorrhages during a mean follow-up period of 23.9+/-14.8 months, yielding a 2-year cumulative rate of recurrence of 21 percent. The apolipoprotein E genotype was significantly associated with the risk of recurrence. Carriers of the epsilon2 or epsilon4 allele had a two-year rate of recurrence of 28 percent, as compared with only 10 percent for patients with the common apolipoprotein E epsilon3/epsilon3 genotype (risk ratio, 3.8; 95 percent confidence interval, 1.2 to 11.6; P=0.01). Early recurrence occurred in eight patients, four of whom had the uncommon epsilon2/epsilon4 genotype. Also at increased risk for recurrence were patients with a history of hemorrhagic stroke before entry into the study (two-year recurrence, 61 percent; risk ratio, 6.4; 95 percent confidence interval, 2.2 to 18.5; P<0.001).
  
  
  CONCLUSIONS
  The apolipoprotein E genotype can identify patients with lobar intracerebral hemorrhage who are at highest risk for early recurrence. This finding makes possible both the provision of prognostic information to patients with lobar hemorrhage and a method of targeting and assessing potential strategies for prevention.
authors.affiliation: Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston 02114, USA.
authors.forename: H C
authors.initials: HC
authors.lastname: O'Donnell
authors.forename: J
authors.initials: J
authors.lastname: Rosand
authors.forename: K A
authors.initials: KA
authors.lastname: Knudsen
authors.forename: K L
authors.initials: KL
authors.lastname: Furie
authors.forename: A Z
authors.initials: AZ
authors.lastname: Segal
authors.forename: R I
authors.initials: RI
authors.lastname: Chiu
authors.forename: D
authors.initials: D
authors.lastname: Ikeda
authors.forename: S M
authors.initials: SM
authors.lastname: Greenberg
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001057:Apolipoproteins E / Q000235:genetics*; D016657:Cerebral Amyloid Angiopathy / Q000150:complications / Q000235:genetics* / Q000473:pathology; D002543:Cerebral Hemorrhage / Q000209:etiology / Q000235:genetics*; D005260:Female; D005838:Genotype; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016133:Polymerase Chain Reaction; D011379:Prognosis; D016016:Proportional Hazards Models; D012008:Recurrence; D012307:Risk Factors
chemical_list: D001057:Apolipoproteins E