The Association between APOE Genotype and Memory Dysfunction in Subjects with Mild Cognitive Impairment Is Related to Age and Alzheimer Pathology

• Published in: Dementia and geriatric cognitive disorders Vol. 26; no. 2; pp. 101 - 108
• Main Authors: Ramakers, I.H.G.B., Visser, P.J., Aalten, P., Bekers, O., Sleegers, K., van Broeckhoven, C.L., Jolles, J., Verhey, F.R.J.
• Format: Journal Article
• Language: English
• Published: Basel, Switzerland Karger 01.01.2008; S. Karger AG
• Subjects: Aged; Alzheimer Disease - genetics; Alzheimer Disease - pathology; Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; Apolipoprotein E4 - genetics; Biological and medical sciences; Cognition Disorders - genetics; Cognition Disorders - pathology; Degenerative and inherited degenerative diseases of the nervous system. Leukodystrophies. Prion diseases; Emergency and intensive cardiocirculatory care. Cardiogenic shock. Coronary intensive care; Female; Follow-Up Studies; Genetic Predisposition to Disease; Genotype; Humans; Intensive care medicine; Logistic Models; Male; Medical sciences; Memory Disorders - genetics; Memory Disorders - pathology; Middle Aged; Neurology; Original Research Article; Severity of Illness Index; Memory strategies; Apolipoprotein E; Mild cognitive impairment; Alzheimer's disease; Human; Nervous system diseases; Cognitive disorder; Alzheimer disease; Memory; Genotype; Cerebral disorder; Anatomic pathology; Central nervous system disease; mild cognitive impairment; Degenerative disease
• ISSN: 1420-8008; 1421-9824; 1421-9824
• DOI: 10.1159/000144072

Background: Memory problems are a main feature of mild cognitive impairment (MCI) and may be related to the apolipoprotein E (APOE) Ε4 allele. We investigated whether the effect of the APOE genotype on memory in subjects with MCI was dependent on age and underlying Alzheimer disease (AD) pathology. Methods: Subjects with MCI (n = 180) were selected from a memory clinic setting. Subjects with at least one APOE Ε4 allele (n = 83) were compared to non-carriers on several memory measures. Subjects were reassessed 5–10 years later in order to identify those who developed AD. Results: In the middle-aged subgroup, the APOE Ε4 allele was most strongly related to decreased subjective organization and in the old subgroup to a decreased delayed recall. After excluding subjects with incipient AD (n = 33), results remained similar in the middle-aged subgroup, but in the old subgroup the APOE genotype was no longer associated with memory dysfunction. Conclusion: The presence of the APOE Ε4 allele is associated with impaired memory functioning in both middle-aged and old subjects with MCI, although the memory function affected varies with age. Its effect on memory function may be dependent on underlying AD pathology in elderly subjects, but not in middle-aged subjects.