Longitudinal stability of medial temporal lobe connectivity is associated with tau-related memory decline
- University of Rochester, United States
Abstract
The relationship between AD pathology and cognitive decline is an important topic in the aging research field. Recent studies suggest that memory deficits are more susceptible to phosphorylated tau (Ptau), than amyloid-beta. However, little is known regarding the neurocognitive mechanisms linking Ptau and memory related decline. Here, we extracted data from ADNI participants with CSF (cerebrospinal fluid) Ptau collected at baseline, diffusion tensor imaging measure twice, two-year apart, and longitudinal memory data over five years. We defined three age- and education-matched groups: Ptau negative cognitively unimpaired, Ptau positive cognitively unimpaired, and Ptau positive individuals with mild cognitive impairment. We found the presence of CSF Ptau at baseline was related to a loss of structural stability in medial temporal lobe connectivity in a way that matched proposed disease progression, and this loss of stability in connections known to be important for memory moderated the relationship between Ptau accumulation and memory decline.
Data availability
Data used in preparation of this article were obtained from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database (adni.loni.usc.edu). As such, the investigators within the ADNI contributed to the design and implementation of ADNI and/or provided data but did not participate in analysis or writing of this report. A complete listing of ADNI investigators can be found at: http://adni.loni.usc.edu/wp-content/uploads/how_to_apply/ADNI_Acknowledgement_List.pdf
Article and author information
Author details
Funding
National Institutes of Health (R01 NR015452)
- Feng V Lin
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: Human subjects: The current study is a secondary data analysis of limited-identified data per data user agreement between ADNI and F.L.. The human subject research of original ADNI data collection was conducted at each ADNI data collection site (see the full list of sites http://adni.loni.usc.edu/wp-content/uploads/how_to_apply/ADNI_Acknowledgement_List.pdf); and written informed consent was obtained from each participant (see http://adni.loni.usc.edu/wp-content/uploads/2008/07/adni2-procedures-manual.pdf for detailed information about ethical procedures for ADNI). Protocol_11.19.14
Copyright
© 2020, Chen et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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