Small vessel disease more than Alzheimer's disease determines diffusion MRI alterations in memory clinic patients.
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ABSTRACT: Introduction
Microstructural alterations as assessed by diffusion tensor imaging (DTI) are key findings in both Alzheimer's disease (AD) and small vessel disease (SVD). We determined the contribution of each of these conditions to diffusion alterations.Methods
We studied six samples (N = 365 participants) covering the spectrum of AD and SVD, including genetically defined samples. We calculated diffusion measures from DTI and free water imaging. Simple linear, multivariable random forest, and voxel-based regressions were used to evaluate associations between AD biomarkers (amyloid beta, tau), SVD imaging markers, and diffusion measures.Results
SVD markers were strongly associated with diffusion measures and showed a higher contribution than AD biomarkers in multivariable analysis across all memory clinic samples. Voxel-wise analyses between tau and diffusion measures were not significant.Discussion
In memory clinic patients, the effect of SVD on diffusion alterations largely exceeds the effect of AD, supporting the value of diffusion measures as markers of SVD.
SUBMITTER: Finsterwalder S
PROVIDER: S-EPMC8102202 | biostudies-literature | 2020 Nov
REPOSITORIES: biostudies-literature
Publications
Small vessel disease more than Alzheimer's disease determines diffusion MRI alterations in memory clinic patients.
Finsterwalder Sofia S Vlegels Naomi N Gesierich Benno B Araque Caballero Miguel Á MÁ Weaver Nick A NA Franzmeier Nicolai N Georgakis Marios K MK Konieczny Marek J MJ Koek Huiberdina L HL Karch Celeste M CM Graff-Radford Neill R NR Salloway Stephen S Oh Hwamee H Allegri Ricardo F RF Chhatwal Jasmeer P JP Jessen Frank F Düzel Emrah E Dobisch Laura L Metzger Coraline C Peters Oliver O Incesoy Enise I EI Priller Josef J Spruth Eike J EJ Schneider Anja A Fließbach Klaus K Buerger Katharina K Janowitz Daniel D Teipel Stefan J SJ Kilimann Ingo I Laske Christoph C Buchmann Martina M Heneka Michael T MT Brosseron Frederic F Spottke Annika A Roy Nina N Ertl-Wagner Birgit B Scheffler Klaus K Seo Sang Won SW Kim Yeshin Y Na Duk L DL Kim Hee Jin HJ Jang Hyemin H Ewers Michael M Levin Johannes J Schmidt Reinhold R Pasternak Ofer O Dichgans Martin M Biessels Geert Jan GJ Duering Marco M
Alzheimer's & dementia : the journal of the Alzheimer's Association 20200818 11
<h4>Introduction</h4>Microstructural alterations as assessed by diffusion tensor imaging (DTI) are key findings in both Alzheimer's disease (AD) and small vessel disease (SVD). We determined the contribution of each of these conditions to diffusion alterations.<h4>Methods</h4>We studied six samples (N = 365 participants) covering the spectrum of AD and SVD, including genetically defined samples. We calculated diffusion measures from DTI and free water imaging. Simple linear, multivariable random ...[more]
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