Clinical-neuroimaging characteristics of dysexecutive mild cognitive impairment.
OBJECTIVE
Subgroups of mild cognitive impairment (MCI) have been proposed, but few studies have investigated the nonamnestic, single-domain subgroup of MCI. The goal of the study was to compare clinical and neuroimaging characteristics of two single-domain MCI subgroups: amnestic MCI and dysexecutive MCI.


METHODS
We compared the cognitive, functional, behavioral, and brain imaging characteristics of patients with amnestic MCI (n = 26), patients with dysexecutive MCI (n = 32), and age- and education-matched control subjects (n = 36) using analysis of variance and chi(2) tests. We used voxel-based morphometry to examine group differences in brain magnetic resonance imaging atrophy patterns.


RESULTS
Patients with dysexecutive MCI had significantly lower scores on the majority of executive function tests, increased behavioral symptoms, and left prefrontal cortex atrophy on magnetic resonance imaging when compared with control subjects. In contrast, patients with amnestic MCI had significantly lower scores on tests of memory and a pattern of atrophy including bilateral hippocampi and entorhinal cortex, right inferior parietal cortex, and posterior cingulate gyrus when compared with control subjects.


CONCLUSIONS
Overall, the clinical and neuroimaging findings provide support for two distinct single-domain subgroups of MCI, one involving executive function and the other involving memory. The brain imaging differences suggest that the two MCI subgroups have distinct patterns of brain atrophy.
Pa
Judy
J
Memory and Aging Center, Department of Neurology, University of California, San Francisco, CA 94117, USA.
Boxer
Adam
A
Chao
Linda L
LL
Gazzaley
Adam
A
Freeman
Katie
K
Kramer
Joel
J
Miller
Bruce L
BL
Weiner
Michael W
MW
Neuhaus
John
J
Johnson
Julene K
JK
D000203:Activities of Daily Living; D000368:Aged; D053327:Apolipoprotein E4 / Q000235:genetics; D001284:Atrophy / Q000473:pathology / Q000503:physiopathology; D001519:Behavior / Q000502:physiology; D001931:Brain Mapping; D016022:Case-Control Studies; D003072:Cognition Disorders / Q000235:genetics / Q000473:pathology* / Q000503:physiopathology* / Q000523:psychology; D005260:Female; D007839:Functional Laterality; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008568:Memory / Q000502:physiology; D008609:Mental Status Schedule; D008875:Middle Aged; D009483:Neuropsychological Tests; D017397:Prefrontal Cortex / Q000473:pathology; D011340:Problem Solving / Q000502:physiology*; D011446:Prospective Studies; D011795:Surveys and Questionnaires
D053327:Apolipoprotein E4