Apolipoprotein E epsilon 4 allele is associated with increased atrophy in progressive mild cognitive impairment: a voxel-based morphometric study.
BACKGROUND
The apolipoprotein E (APOE) epsilon4 allele is a risk factor for Alzheimer's disease. Earlier studies have shown differences in brain structure according to the APOE epsilon4 status.


OBJECTIVE
To assess possible differences in brain structure according to the APOE epsilon4 status in mild cognitive impairment (MCI) subjects in relation to conversion to dementia.


METHODS
In a follow-up study of 56 MCI subjects, 13 MCI subjects progressed to dementia (PMCI) during a mean follow-up time of 31 months. Brain structure differences in both stable MCI (SMCI) and PMCI epsilon4 carriers and noncarriers in the baseline MRI scan were assessed with voxel-based morphometry.


RESULTS
The SMCI epsilon4 carriers had atrophy in the amygdala and hippocampus compared to the SMCI noncarriers. The PMCI epsilon4 carriers revealed atrophy of the left inferior frontal gyrus and parietal cortex compared to the PMCI noncarriers.


CONCLUSIONS
The rate of brain atrophy in certain brain areas may be increased in epsilon4-positive MCI subjects progressing to dementia.
Hämäläinen
A
A
Department of Neuroscience and Neurology, University of Kuopio and Brain Research Unit, Clinical Research Center, Mediteknia, Kuopio, Finland.
Grau-Olivares
M
M
Tervo
S
S
Niskanen
E
E
Pennanen
C
C
Huuskonen
J
J
Kivipelto
M
M
Hänninen
T
T
Tapiola
M
M
Vanhanen
M
M
Hallikainen
M
M
Helkala
E-L
EL
Nissinen
A
A
Vanninen
R L
RL
Soininen
H
H
D000368:Aged; D000369:Aged, 80 and over; D000483:Alleles; D053327:Apolipoprotein E4 / Q000096:biosynthesis / Q000235:genetics*; D001284:Atrophy; D001931:Brain Mapping / Q000379:methods; D002540:Cerebral Cortex / Q000473:pathology* / Q000502:physiology; D003072:Cognition Disorders / Q000235:genetics* / Q000473:pathology* / Q000523:psychology; D015331:Cohort Studies; D003704:Dementia / Q000235:genetics* / Q000473:pathology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D012307:Risk Factors
D053327:Apolipoprotein E4