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- Fjell, Anders M., et al.
(författare)
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Self-reported sleep relates to hippocampal atrophy across the adult lifespan : results from the Lifebrain consortium
- 2020
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Ingår i: Sleep. - : Oxford University Press. - 0161-8105 .- 1550-9109. ; 43:5
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Tidskriftsartikel (refereegranskat)abstract
- Objectives: Poor sleep is associated with multiple age-related neurodegenerative and neuropsychiatric conditions. The hippocampus plays a special role in sleep and sleep-dependent cognition, and accelerated hippocampal atrophy is typically seen with higher age. Hence, it is critical to establish how the relationship between sleep and hippocampal volume loss unfolds across the adult lifespan.Methods: Self-reported sleep measures and MRI-derived hippocampal volumes were obtained from 3105 cognitively normal participants (18–90 years) from major European brain studies in the Lifebrain consortium. Hippocampal volume change was estimated from 5116 MRIs from 1299 participants for whom longitudinal MRIs were available, followed up to 11 years with a mean interval of 3.3 years. Cross-sectional analyses were repeated in a sample of 21,390 participants from the UK Biobank.Results: No cross-sectional sleep—hippocampal volume relationships were found. However, worse sleep quality, efficiency, problems, and daytime tiredness were related to greater hippocampal volume loss over time, with high scorers showing 0.22% greater annual loss than low scorers. The relationship between sleep and hippocampal atrophy did not vary across age. Simulations showed that the observed longitudinal effects were too small to be detected as age-interactions in the cross-sectional analyses.Conclusions: Worse self-reported sleep is associated with higher rates of hippocampal volume decline across the adult lifespan. This suggests that sleep is relevant to understand individual differences in hippocampal atrophy, but limited effect sizes call for cautious interpretation.
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| 2. |
- Halaas, Nathalie Bodd, et al.
(författare)
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CSF sTREM2 and Tau Work Together in Predicting Increased Temporal Lobe Atrophy in Older Adults.
- 2020
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Ingår i: Cerebral cortex (New York, N.Y. : 1991). - : Oxford University Press (OUP). - 1460-2199 .- 1047-3211. ; 30:4, s. 2295-2306
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Tidskriftsartikel (refereegranskat)abstract
- Neuroinflammation may be a key factor in brain atrophy in aging and age-related neurodegenerative disease. The objective of this study was to test the association between microglial expression of soluble Triggering Receptor Expressed on Myeloid Cells 2 (sTREM2), as a measure of neuroinflammation, and brain atrophy in cognitively unimpaired older adults. Brain magnetic resonance imagings (MRIs) and cerebrospinal fluid (CSF) sTREM2, total tau (t-tau), phosphorylated181 tau (p-tau), and Aβ42 were analyzed in 115 cognitively unimpaired older adults, classified according to the A/T/(N)-framework. MRIs were repeated after 2 (n = 95) and 4 (n = 62) years. High baseline sTREM2 was associated with accelerated cortical thinning in the temporal cortex of the left hemisphere, as well as bilateral hippocampal atrophy, independently of age, Aβ42, and tau. sTREM2-related atrophy only marginally increased with biomarker positivity across the AD continuum (A-T- #x2292; A+T- #x2292; A+T+) but was significantly stronger in participants with a high level of p-tau (T+). sTREM2-related cortical thinning correlated significantly with areas of high microglial-specific gene expression in the Allen Human Brain Atlas. In conclusion, increased CSF sTREM2 was associated with accelerated cortical and hippocampal atrophy in cognitively unimpaired older participants, particularly in individuals with tau pathology. This suggests a link between neuroinflammation, neurodegeneration, and amyloid-independent tauopathy.
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