Dissociation of neuropathologic findings and cognition: case report of an apolipoprotein E epsilon2/epsilon2 genotype.

Abstract

BACKGROUND:

The apolipoprotein E (APOE) epsilon2 allele has been suggested as having a protective effect and delaying the age at onset of Alzheimer disease.

OBJECTIVE:

To describe a dissociation between neuropathologic findings with normal cognition in a woman with severe Alzheimer disease with the APOE epsilon2/epsilon2 genotype.

DESIGN:

Case report from a community-based prospective study of persons 90 years or older (The 90+ Study).

PARTICIPANT:

A 92-year-old woman without dementia with the APOE epsilon2/epsilon2 genotype who lived independently without significant cognitive or functional loss and was a participant in The 90+ Study. She died in December 2004, and postmortem examination of her brain was performed.

INTERVENTION:

Neurologic examination and a battery of neuropsychological tests were performed 6 months and 1 month before death. Neuropathologic examination included Braak and Braak staging for senile plaques and neurofibrillary tangles.

RESULTS:

Neuropathologic examination of the brain revealed advanced senile plaque and neurofibrillary tangle disease consistent with a high likelihood of Alzheimer disease. At clinical evaluation, the participant demonstrated no dementia and only mild cognitive deficits.

CONCLUSIONS:

The APOE genotype may have contributed to maintenance of cognition despite advanced neuropathologic findings of Alzheimer disease. This case suggests that the APOE epsilon2 isoform may have a protective effect against cognitive decline in Alzheimer disease that may be independent from senile plaques and neurofibrillary tangles.

• Authors: Daniel J Berlau, Kristin Kahle-Wrobleski, Elizabeth Head, Matthew Goodus, Ronald Kim, Claudia Kawas
• Journal: Archives of neurology (Arch Neurol) Vol. 64 Issue 8 Pg. 1193-6 (Aug 2007) ISSN: 0003-9942 [Print] United States
• PMID: 17698712 (Publication Type: Case Reports, Journal Article, Research Support, N.I.H., Extramural)

Chemical References

• Apolipoprotein E2

Topics

• Aged, 80 and over
• Alzheimer Disease (diagnosis, genetics, pathology, psychology)
• Apolipoprotein E2 (genetics)
• Brain (pathology)
• Cognition
• Female
• Genotype
• Humans
• Neurofibrillary Tangles (pathology)
• Neurologic Examination
• Neuropsychological Tests
• Plaque, Amyloid (pathology)