Publications by authors named "Rebecca E. Langhough"
Importance: Alzheimer disease (AD) predominates in females at almost twice the rate relative to males. Mounting evidence in adults without AD indicates that females exhibit higher tau deposition than age-matched males, particularly in the setting of elevated β-amyloid (Aβ), but the evidence for sex differences in tau accumulation rates is inconclusive.
Objective: To examine whether female sex is associated with faster tau accumulation in the setting of high Aβ (as measured with positron emission tomography [PET]) and the moderating influence of sex on the association between APOEε4 carrier status and tau accumulation.
Background: Alzheimer's disease (AD) can be diagnosed by in vivo abnormalities of amyloid-β plaques (A) and tau accumulation (T) biomarkers. Previous studies have shown that analyses of serial position performance in episodic memory tests, and especially, delayed primacy, are associated with AD pathology even in individuals who are cognitively unimpaired. The earliest signs of cortical tau pathology are observed in medial temporal lobe (MTL) regions, yet it is unknown if serial position markers are also associated with early tau load in these regions.
View Article and Find Full Text PDFIntroduction: Targeted proteomic assays may be useful for diagnosing and staging Alzheimer's disease and related dementias (ADRD). We evaluated the performance of a 120-marker central nervous system (CNS) NUcleic acid-Linked Immuno-Sandwich Assay (NULISA) panel in samples spanning the AD spectrum.
Methods: Cross-sectional plasma samples (n=252) were analyzed using Alamar's NULISAseq CNS panel.
Visual read of [F-18]florquinitau PET that includes and extends beyond the mesial temporal lobe is associated with increased plasma pTau217 and cognitive decline in a cohort that is enriched with risk for Alzheimer's disease.
Alzheimers Dement
February 2025
Introduction: Patterns of signal from tau positron emission tomography (tau-PET) confined to the medial temporal lobe (MTL) or extended into the neocortex may be relevant for Alzheimer's disease (AD) research if they are linked to differential biomarker levels and cognitive decline.
Methods: Visual assessment of Tau-PET [F-18]florquinitau (FQT) exams from 728 initially non-demented older adults yielded four uptake groups: tau-negative (T-), MTL-only (T+), neocortex-only (T+), or both (T+). Mixed effects models assessed group differences in retrospective cognitive and plasma pTau217 trajectories.
Article Synopsis
- This study focuses on identifying individuals with advanced Alzheimer's disease (specifically Braak V or VI) using plasma biomarkers in those who are already confirmed to have amyloid-β (Aβ).
- Researchers evaluated 595 participants from two studies, employing tests like amyloid-PET and tau-PET while measuring various plasma tau levels.
- Findings suggest that elevated levels of plasma pTau-217 are strongly associated with Braak V positivity, indicating it could be a useful biomarker for patient stratification in treatment and clinical studies.
Introduction: Multi-etiology dementia necessitates in-vivo markers of copathologies including misfolded -synuclein (syn). We measured misfolded syn aggregates (syn-seeds) via qualitative seed amplifcation assays (synSAA) and examined relationships with markers of Alzheimer's disease (AD).
Methods: Cerebrospinal fluid (CSF) was obtained from 420 participants in two Wisconsin AD risk cohorts (35% male; 91% cognitively unimpaired; mean (SD) age, 65.
The current study examined the longitudinal relationship between cognitive reserve (CR), depression, and executive function (EF) in a cohort of older adults. : 416 participants were selected from the Wisconsin Registry for Alzheimer's Prevention. They were native English speakers, aged ≥50+, and cognitively unimpaired at baseline, with no history of neurological or other psychiatric disorders aside from depression.
View Article and Find Full Text PDFBackground: Early detection of Alzheimer's disease (AD) is one of the critical components of the global response to the growing dementia crisis. Analysis of serial position performance in story recall tests has yielded sensitive metrics for the prediction of AD at low cost. In this study, we examined whether serial position markers in two story recall tests (the logical memory test, LMT, and the Craft Story 21 test, CST) were sensitive to cross-sectional biomarker-based assessment of in vivo neuropathology.
View Article and Find Full Text PDFIntroduction: Understanding longitudinal change in key plasma biomarkers will aid in detecting presymptomatic Alzheimer's disease (AD).
Methods: Serial plasma samples from 424 Wisconsin Registry for Alzheimer's Prevention participants were analyzed for phosphorylated-tau217 (p-tau217; ALZpath) and other AD biomarkers, to study longitudinal trajectories in relation to disease, health factors, and cognitive decline. Of the participants, 18.
Objective: Neighborhood disadvantage is associated with worse health and cognitive outcomes. Morphological similarity network (MSN) is a promising approach to elucidate cortical network patterns underlying complex cognitive functions. We hypothesized that MSNs could capture intricate changes in cortical patterns related to neighborhood disadvantage and cognitive function, potentially explaining some of the risk for later life cognitive impairment among individuals who live in disadvantaged contexts.
View Article and Find Full Text PDFRecent longitudinal PET imaging studies have established methods to estimate the age at which amyloid becomes abnormal at the level of the individual. Here we recontextualized amyloid levels into the temporal domain to better understand the downstream Alzheimer's disease processes of tau neurofibrillary tangle (NFT) accumulation and cognitive decline. This cohort study included a total of 601 individuals from the Wisconsin Registry for Alzheimer's Prevention and Wisconsin Alzheimer's Disease Research Center that underwent amyloid and tau PET, longitudinal neuropsychological assessments and met clinical criteria for three clinical diagnosis groups: cognitively unimpaired (n = 537); mild cognitive impairment (n = 48); or dementia (n = 16).
View Article and Find Full Text PDFArticle Synopsis
- Published norms typically miss early cognitive changes linked to dementia, prompting the development of new standards using data from two Alzheimer's risk cohorts.
- The research utilized quantitative regression to create both cross-sectional and longitudinal normative standards based on data from nearly 1,400 cognitively healthy participants over an average of 9 years.
- Findings indicate that lower percentile scores correlate with cognitive impairment and higher Alzheimer’s biomarker levels, while a ShinyApp was created to help visualize scores and identify low performance.
Neurovascular 4D-Flow MRI enables non-invasive evaluation of cerebral hemodynamics including measures of cerebral blood flow (CBF), vessel pulsatility index (PI), and cerebral pulse wave velocity (PWV). 4D-Flow measures have been linked to various neurovascular disorders including small vessel disease and Alzheimer's disease; however, physiological and technical sources of variability are not well established. Here, we characterized sources of diurnal physiological and technical variability in cerebral hemodynamics using 4D-Flow in a retrospective study of cognitively unimpaired older adults (N = 750) and a prospective study of younger adults (N = 10).
View Article and Find Full Text PDFArticle Synopsis
- Phosphorylated tau (p-tau) is a key blood biomarker for detecting Alzheimer disease (AD), with p-tau217 being particularly useful; however, access to p-tau217 tests has been limited, hindering research and clinical applications.
- The study aimed to evaluate a new commercial immunoassay for plasma p-tau217, focusing on its ability to detect AD pathology and establish reference ranges for abnormal amyloid β (Aβ) across three different cohorts.
- Involving 786 participants, the study found that plasma p-tau217 demonstrated high accuracy (AUC 0.92-0.96) in identifying elevated Aβ and tau pathology, suggesting its effectiveness as
Article Synopsis
- Phosphorylated tau (pTau217) is a promising blood biomarker for Alzheimer's disease, but its availability for tests in research and clinical settings has been limited, highlighting the need for broader access.
- The study aimed to assess the effectiveness of a new plasma pTau217 test (ALZpath) to detect Alzheimer's pathology and to evaluate reference ranges for abnormal amyloid across three observational cohorts.
- Results from 786 participants showed pTau217 had high accuracy (0.92-0.97) in identifying abnormal amyloid and tau pathology, outperforming other plasma biomarker combinations and matching the accuracy of established imaging methods.