Episodic Memory and Hippocampal Volume Predict 5-Year Mild Cognitive Impairment Conversion in Healthy Apolipoprotein ε4 Carriers. J Int Neuropsychol Soc 2020 Aug;26(7):733-738
Date
03/07/2020Pubmed ID
32131913Pubmed Central ID
PMC7423643DOI
10.1017/S1355617720000181Scopus ID
2-s2.0-85082035366 (requires institutional sign-in at Scopus site) 8 CitationsAbstract
OBJECTIVE: The Apolipoprotein (APOE) ε4 allele increases the risk for mild cognitive impairment (MCI) and dementia, but not all carriers develop MCI/dementia. The purpose of this exploratory study was to determine if early and subtle preclinical signs of cognitive dysfunction and medial temporal lobe atrophy are observed in cognitively intact ε4 carriers who subsequently develop MCI.
METHODS: Twenty-nine healthy, cognitively intact ε4 carriers (ε3/ε4 heterozygotes; ages 65-85) underwent neuropsychological testing and MRI-based measurements of medial temporal volumes over a 5-year follow-up interval; data were converted to z-scores based on a non-carrier group consisting of 17 ε3/ε3 homozygotes.
RESULTS: At follow-up, 11 ε4 carriers (38%) converted to a diagnosis of MCI. At study entry, the MCI converters had significantly lower scores on the Mini-Mental State Examination, Rey Auditory Verbal Learning Test (RAVLT) Trials 1-5, and RAVLT Immediate Recall compared to non-converters. MCI converters also had smaller MRI volumes in the left subiculum than non-converters. Follow-up logistic regressions revealed that left subiculum volumes and RAVLT Trials 1-5 scores were significant predictors of MCI conversion.
CONCLUSIONS: Results from this exploratory study suggest that ε4 carriers who convert to MCI exhibit subtle cognitive and volumetric differences years prior to diagnosis.
Author List
Abraham M, Seidenberg M, Kelly DA, Nielson KA, Woodard JL, Carson Smith J, Durgerian S, Rao SMAuthor
Kristy Nielson PhD Professor in the Psychology department at Marquette UniversityMESH terms used to index this publication - Major topics in bold
AgedAged, 80 and over
Apolipoprotein E4
Atrophy
Cognitive Dysfunction
Female
Heterozygote
Hippocampus
Humans
Magnetic Resonance Imaging
Male
Memory, Episodic
Neuropsychological Tests
Risk Factors