APOE ε4 influences within and between network functional connectivity in posterior cortical atrophy and logopenic progressive aphasia.

ABSTRACT:

Introduction

Presence of apolipoprotein E (APOE) ε4 has shown greater predisposition to medial temporal involvement in posterior cortical atrophy (PCA) and logopenic progressive aphasia (LPA). Little is known about its influence on memory network connectivity, a network comprised of medial temporal structures.

Methods

Fifty-eight PCA and 82 LPA patients underwent structural and resting state functional magnetic resonance imaging (MRI). Bayesian hierarchical linear models assessed the influence of APOE ε4 on within and between-network connectivity for five networks.

Results

APOE ε4 carriers showed reduced memory and language within-network connectivity in LPA and increased salience within-network connectivity in PCA compared to non-carriers. Between-network analysis showed evidence of reduced DMN connectivity in APOE ε4 carriers, with reduced DMN-to-salience and DMN-to-language network connectivity in PCA, and reduced DMN-to-visual network connectivity in LPA.

Discussion

The APOE genotype influences brain connectivity, both within and between-networks, in atypical Alzheimer's disease. However, there was evidence that the modulatory effects of APOE differ across phenotype.

Highlights

APOE genotype is associated with reductions in within-network connectivity for the memory and language networks in LPA APOE genotype is associated with reductions in language-to-visual connectivity in LPA and PCA APOE genotype has no effect on the memory network in PCA.

SUBMITTER: Singh NA 

PROVIDER: S-EPMC10523970 | biostudies-literature | 2023 Sep

REPOSITORIES: biostudies-literature