Publications by authors named "J Fripp"
Sleep discrepancy (negative discrepancy reflects worse self-reported sleep than objective measures, such as actigraphy, and positive discrepancy the opposite) has been linked to adverse health outcomes. This study is first to investigate the relationship between sleep discrepancy and brain glucose metabolism (assessed globally and regionally via positron emission tomography), and to evaluate the contribution of insomnia severity and depressive symptoms to any associations. Using data from cognitively unimpaired community-dwelling older adults ( = 68), cluster analysis was used to characterise sleep discrepancy (for total sleep time (TST), wake after sleep onset (WASO), and sleep efficiency (SE)), and logistic regression was used to explore sleep discrepancy's associations with brain glucose metabolism, while controlling for insomnia severity and depressive symptoms.
View Article and Find Full Text PDFDeficits in memory are seen as a canonical sign of aging and a prodrome to dementia in older adults. However, our understanding of age-related cognition and brain morphology occurring throughout a broader spectrum of adulthood remains limited. We quantified the relationship between cognitive function and brain morphology (sulcal width, SW) using three cross-sectional observational datasets (PISA, AIBL, ADNI) from mid-life to older adulthood, assessing the influence of age, sex, amyloid (Aβ) and genetic risk for dementia.
View Article and Find Full Text PDFThe current study compared the reliability of manual collateral sulcus depth and entorhinal and transentorhinal cortical volume measurements between native oriented MRI scans versus MRI scans realigned to the hippocampal long axis. Data included 10 participants with two serial 3.0T MRI scans from the Alzheimer's Disease Neuroimaging Initiative.
View Article and Find Full Text PDFArticle Synopsis
- Plasma phospho-tau 217 (pTau217) assays, when performed on the common Lumipulse-G® platform, can effectively identify Alzheimer's disease (AD) by analyzing β-amyloid (Aβ) status and tau staging in patients.
- In a study with 388 participants, pTau217 showed strong correlations with PET imaging results, achieving high accuracy rates in distinguishing between Aβ-negative and Aβ-positive individuals, as well as different stages of tau pathology.
- The findings suggest that the plasma pTau217 assay is a reliable tool for predicting who might benefit from anti-β-amyloid treatments, emphasizing its potential for broader clinical use in AD diagnostics.
Article Synopsis
- Alzheimer's disease (AD) exhibits varied brain atrophy patterns, identified through a semi-supervised learning technique (Surreal-GAN) that distinguishes between "diffuse-AD" (widespread atrophy) and "MTL-AD" (focal atrophy in the medial temporal lobe) dimensions in patients with mild cognitive impairment (MCI) and AD.
- Only the "MTL-AD" dimension was linked to known AD genetic risk factors like APOE ε4, and both dimensions were later detected in asymptomatic individuals, revealing their association with different genetic and pathological mechanisms.
- Aside from brain-related genes, up to 77 additional genes were identified in various organs, pointing to broader