title: Association between the APOE genotype and psychopathologic symptoms in Alzheimer's disease.
abstract: BACKGROUND
  Psychiatric symptoms occur frequently in the course of AD, are a frequent contributor to institutionalization, predict cognitive decline and death, and often require treatment with psychotropic medications. Previous studies investigating the association between APOE genotype and psychiatric symptomatology in AD have reported contradictory results.
  
  
  OBJECTIVE
  To determine whether APOE genotype predicts incident psychiatric symptomatology in patients with AD.
  
  
  METHODS
  Eighty-seven patients with AD at early stages and no psychiatric history were followed semiannually for up to 9.3 years (mean 5.5 years) for development of delusions, illusions, hallucinations, behavioral symptoms, and depression. Cox proportional hazards models were used to examine the relative risk for incident psychiatric symptomatology (outcome) in relation to APOE genotype (predictor).
  
  
  RESULTS
  The presence of one epsilon4 allele carried a 2.5-fold risk, whereas the presence of two epsilon4 alleles carried a 5.6-fold risk for development of delusions. The associations remained significant even when age, ethnicity, sex, education, duration of disease, and cognitive and functional performance were controlled for. The presence of two epsilon4 alleles was associated with reduced risk for developing hallucinations in the adjusted analysis only. No significant associations were detected between APOE genotype and the incidence of illusions, behavioral symptoms, or depression.
  
  
  CONCLUSIONS
  The presence of one or more epsilon4 alleles is a significant predictor for the incidence of delusions in the course of AD.
authors.affiliation: Cognitive Neuroscience Division, Taub Institute for Research in Alzheimer's Disease and the Aging Brain, New York, NY, USA.
authors.forename: N
authors.initials: N
authors.lastname: Scarmeas
authors.forename: J
authors.initials: J
authors.lastname: Brandt
authors.forename: M
authors.initials: M
authors.lastname: Albert
authors.forename: D P
authors.initials: DP
authors.lastname: Devanand
authors.forename: K
authors.initials: K
authors.lastname: Marder
authors.forename: K
authors.initials: K
authors.lastname: Bell
authors.forename: A
authors.initials: A
authors.lastname: Ciappa
authors.forename: B
authors.initials: B
authors.lastname: Tycko
authors.forename: Y
authors.initials: Y
authors.lastname: Stern
mesh_terms: D000368:Aged; D000483:Alleles; D000544:Alzheimer Disease / Q000235:genetics* / Q000523:psychology*; D001057:Apolipoproteins E / Q000235:genetics*; D003710:Demography; D005260:Female; D006801:Humans; D008297:Male; D008960:Models, Psychological; D011446:Prospective Studies; D011569:Psychiatric Status Rating Scales; D018570:Risk Assessment
chemical_list: D001057:Apolipoproteins E