Spectral analysis of EEG in Alzheimer's disease: relation to apolipoprotein E polymorphism.
Apolipoprotein E (ApoE) epsilon 4 allele is a risk factor for late-onset Alzheimer's disease (AD) and proposed to have a direct impact on cholinergic function in AD. Slowing of the EEG is characteristic in AD and the cholinergic system has an important role in modulating EEG. Fifty-eight AD patients at the early stage of the disease and 34 age- and sex-matched controls were studied using the quantitative EEG recorded from T6-O2 derivation. AD patients were divided into two subgroups: a) according to the ApoE allele (2 epsilon, 1 epsilon 4, and 0 epsilon 4) and b) according to familial aggregation. AD subgroups did not differ in clinical severity or duration of dementia. The AD patients with the epsilon 4 allele had higher relative theta amplitude and lower relative beta amplitude than controls and patients without the epsilon 4 allele. The peak frequencies were lower in all AD subgroups compared to controls. In conclusion, we found a tendency towards more pronounced EEG slowing in AD patients carrying the epsilon 4 allele. The minor differences in EEG may suggest differences in the degree of the cholinergic deficit in these subgroups.
Lehtovirta
M
M
Department of Neurology, University Hospital, University of Kuopio, Finland.
Partanen
J
J
Könönen
M
M
Soininen
H
H
Helisalmi
S
S
Mannermaa
A
A
Ryynänen
M
M
Hartikainen
P
P
Riekkinen
P
P
D000368:Aged; D000483:Alleles; D000544:Alzheimer Disease / Q000235:genetics / Q000503:physiopathology*; D001057:Apolipoproteins E / Q000235:genetics*; D004569:Electroencephalography; D005260:Female; D006801:Humans; D008297:Male; D011110:Polymorphism, Genetic
D001057:Apolipoproteins E