Impact of APOE in mild cognitive impairment.
OBJECTIVE
The authors aimed to use baseline data of an ongoing large, prospective study in subjects with mild cognitive impairment (MCI) to investigate the impact of APOE genotype on the symptom profile of the condition.


METHODS
Cognitive assessments included the AD Assessment Scale cognitive subscale (ADAS-cog), the Mini-Mental State Examination (MMSE), and a cognitive battery for assessment of memory, attention, and executive function. Behavioral assessments included the Neuropsychiatric Inventory and Beck Depression Inventory. Activities of daily living were assessed by the AD Cooperative Study Activities of Daily Living (ADCS-ADL) scale. Hippocampal volumes were measured with MRI.


RESULTS
A total of 494 of 1,018 study subjects provided APOE data. Approximately 40% of the subjects were APOE epsilon4 carriers. APOE epsilon4 carriers had lower MMSE (p = 0.01) and higher ADAS-cog (p < 0.0001) scores than noncarriers, indicating worse cognitive impairment. APOE epsilon4 carriers also had greater deficits on New York University delayed paragraph recall and Buschke free and cued selective reminding tests, and on the ADCS-ADL scale (p < 0.001). They also had smaller hippocampal volumes (p = 0.002). Behavioral scores were similar across the subgroups.


CONCLUSIONS
MCI subjects carrying the APOE epsilon4 allele showed distinct cognitive and imaging profiles, which appeared to resemble those of early Alzheimer patients. APOE epsilon4 genotype was associated with greater impairments in memory and functional activities as well as hippocampal atrophy.
Farlow
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MR
Department of Neurology, Indiana University School of Medicine, Clinical Building, Room 299, 541 Clinical Drive, Indianapolis, IN 46202-5111, USA. mfarlow@iupui.edu
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D000203:Activities of Daily Living; D000368:Aged; D000369:Aged, 80 and over; D000483:Alleles; D000544:Alzheimer Disease / Q000235:genetics / Q000473:pathology / Q000517:prevention & control; D053327:Apolipoprotein E4; D001057:Apolipoproteins E / Q000235:genetics*; D001284:Atrophy; D003072:Cognition Disorders / Q000188:drug therapy / Q000235:genetics* / Q000473:pathology; D005260:Female; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006624:Hippocampus / Q000473:pathology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D018697:Nootropic Agents / Q000627:therapeutic use; D048448:Phenylcarbamates / Q000627:therapeutic use; D016032:Randomized Controlled Trials as Topic; D000068836:Rivastigmine
D053327:Apolipoprotein E4; D001057:Apolipoproteins E; D018697:Nootropic Agents; D048448:Phenylcarbamates; D000068836:Rivastigmine