Dataset Information

APOE?4 Gene Dose and Sex Effects on Alzheimer's Disease MRI Biomarkers in Older Adults with Mild Cognitive Impairment.

ABSTRACT:

Background

APOE?4 and sex have been linked to increased risk for conversion to Alzheimer's disease (AD). However, the relationship between APOE?4 gene dose, sex, and AD biomarkers remains understudied.

Objective

To investigate the effect of APOE?4 dose on AD biomarkers in a sample of older adults with mild cognitive impairment (MCI), and to examine whether APOE?4 dose modifies AD risk differently in MCI women and men.

Methods

We examined cross-sectional AD biomarkers for participants with MCI (n?=?930, 55-96 years old) from three large aging cohorts. Region of interest MRI volumes, global cognition, and episodic memory were analyzed by number of APOE?4 alleles and stratified by sex.

Results

Across all participants, number of APOE?4 alleles was associated with smaller hippocampal and amygdala volumes and poorer cognition. When stratified by sex, women showed an APOE?4 dose effect for bilateral hippocampal and left amygdala volumes and cognition. In contrast, men showed an APOE?4 dose effect for hippocampal volumes with a trend in amygdala, but cognition did not differ between men with 1 and 2 APOE?4 alleles. Women with 2 APOE?4 alleles had poorer memory between 65-69 and poorer global cognition between 70-74 compared to men with 2 APOE?4 alleles.

Conclusion

APOE?4 confers a dose effect on AD biomarkers in patients with MCI, and the number of APOE?4 alleles has a greater detrimental impact in women than men, which may be specific to a critical time window.

SUBMITTER: Hobel Z

PROVIDER: S-EPMC6839478 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Publications

APOEɛ4 Gene Dose and Sex Effects on Alzheimer's Disease MRI Biomarkers in Older Adults with Mild Cognitive Impairment.

Hobel Zachary Z Isenberg A Lisette AL Raghupathy Dhvani D Mack Wendy W Pa Judy J

Journal of Alzheimer's disease : JAD 20190101 2

<h4>Background</h4>APOEɛ4 and sex have been linked to increased risk for conversion to Alzheimer's disease (AD). However, the relationship between APOEɛ4 gene dose, sex, and AD biomarkers remains understudied.<h4>Objective</h4>To investigate the effect of APOEɛ4 dose on AD biomarkers in a sample of older adults with mild cognitive impairment (MCI), and to examine whether APOEɛ4 dose modifies AD risk differently in MCI women and men.<h4>Methods</h4>We examined cross-sectional AD biomarkers for pa ...[more]

PMID: 31424388

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