title: The apolipoprotein E epsilon 4 allele is not associated with psychiatric symptoms or extrapyramidal signs in probable Alzheimer's disease.
abstract: The objective of our study was to examine the relationship between the presence of the apolipoprotein E (apo E) epsilon 4 allele, psychiatric symptoms, and extrapyramidal signs (EPS) in probable Alzheimer's disease (AD). The apo E epsilon 4 allele modifies the risk and age at onset of AD. However, it still needs to be determined whether it is a marker for specific clinical subgroups. The frequency of clinical signs and symptoms was examined in 194 AD patients with the apo E epsilon 3/3 (N = 79), epsilon 3/4 (N = 96), and epsilon 4/4 (N = 19) genotypes participating in a longitudinal study of dementia. Each patient was assessed with semistructured psychiatric and neurologic examinations. Patients with the epsilon 4/4 genotype had an earlier age at onset of dementia (p = 0.03). However, no individual psychiatric symptom or neurologic sign was associated with the presence of the apo E epsilon 4 allele, including major depression (odds ratio [OR], 1.14; CI, 0.50 to 2.45; p = 0.78), psychosis (e.g., delusions and hallucinations) (OR, 0.66, CI, 0.35 to 1.25; p = 0.20), and EPS (in neuroleptic-free patients) (OR, 0.82, CI, 0.45 to 1.49; p = 0.52), after controlling by age at onset, duration of the symptoms, education, and severity of dementia. The presence of the apo E epsilon 4 allele has limited utility in the characterization of neurologic and psychiatric subgroups in probable AD patients. The apo E epsilon 4/4 genotype appears to be related to age at onset of AD, consistent with previous findings.
authors.affiliation: Alzheimer's Disease Research Center, Department of Neurology, University of Pittsburgh School of Medicine, PA, USA.
authors.forename: O L
authors.initials: OL
authors.lastname: Lopez
authors.forename: M I
authors.initials: MI
authors.lastname: Kamboh
authors.forename: J T
authors.initials: JT
authors.lastname: Becker
authors.forename: D I
authors.initials: DI
authors.lastname: Kaufer
authors.forename: S T
authors.initials: ST
authors.lastname: DeKosky
mesh_terms: D017668:Age of Onset; D000368:Aged; D000483:Alleles; D000544:Alzheimer Disease / Q000175:diagnosis* / Q000235:genetics*; D001057:Apolipoproteins E / Q000235:genetics*; D001480:Basal Ganglia Diseases / Q000175:diagnosis / Q000235:genetics*; D005260:Female; D006801:Humans; D008297:Male; D001523:Mental Disorders / Q000175:diagnosis / Q000235:genetics*; D009460:Neurologic Examination; D011569:Psychiatric Status Rating Scales; D012307:Risk Factors
chemical_list: D001057:Apolipoproteins E