Publications by authors named "Kremers W"

Importance: Although 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) is a well-established cross-sectional biomarker of brain metabolism in dementia with Lewy bodies (DLB), the longitudinal change in FDG-PET has not been characterized.

Objective: To investigate longitudinal FDG-PET in prodromal DLB and DLB, including a subsample with autopsy data, and report estimated sample sizes for a hypothetical clinical trial in DLB.

Design, Setting, And Participants: Longitudinal case-control study with mean (SD) follow-up of 3.

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Cellular senescence is a biological mechanism of aging and age-related diseases. The aim of this study was to examine whether senescence biomarkers are associated with frailty and physical function trajectories in patients undergoing kidney transplantation (KT). We also discussed the relationship between senescence biomarkers and KT function.

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Article Synopsis
  • Physical activity (PA) in older adults is linked to improvements in gait speed and a reduced risk of falls, highlighting its importance for maintaining mobility.
  • A study followed over 4,000 individuals aged 50 and above for about four years, assessing their PA levels and various gait measures using advanced technology.
  • Results showed that higher PA, especially moderate-vigorous activity, correlated with better gait performance and significantly lowered fall risks over time.
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Background: Periprosthetic joint infection (PJI) is an uncommon, but serious complication in total joint arthroplasty. Personalized risk prediction and risk factor management may allow better preoperative assessment and improved outcomes. We evaluated different data-driven approaches to develop surgery-specific PJI prediction models using large-scale data from the electronic health records (EHRs).

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Objective: Few normative data for unsupervised, remotely-administered computerized cognitive measures are available. We examined variables to include in normative models for Mayo Test Drive (a multi-device remote cognitive assessment platform) measures, developed normative data, and validated the norms.

Method: 1240 Cognitively Unimpaired (CU) adults ages 32-100-years (96% white) from the Mayo Clinic Study of Aging and Mayo Alzheimer's Disease Research Center with Clinical Dementia Rating of 0 were included.

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Background: Easily accessible and self-administered cognitive assessments that can aid early detection for Alzheimer's disease (AD) dementia risk are critical for timely intervention.

Objectives/design: This cross-sectional study investigated continuous associations between Mayo Test Drive (MTD) - a remote, self-administered, multi-device compatible, web-based cognitive assessment - and AD-related imaging biomarkers.

Participants/setting: 684 adults from the Mayo Clinic Study of Aging and Mayo Clinic Alzheimer's Disease Research Center participated (age=70.

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Performance-based measures of frailty are associated with healthcare utilization after kidney transplantation (KT) but require in-person assessment. A promising alternative is self-reported frailty. The goal of this study was to examine the ability of performance-based and self-reported frailty measures to predict 30-day rehospitalizations after KT.

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  • Electrophysiologic changes in neurodegenerative disorders like Alzheimer's and Lewy Body disease can be identified using EEG, providing insight into disease severity.
  • Traditional EEG analysis is limited by biases from preset feature selection; this study uses a data-driven tensor decomposition method to extract key EEG activity features during resting states.
  • By analyzing data from over 11,000 patients, the researchers developed an algorithm to differentiate cognitive impairment and dementia types based on identifiable EEG patterns, which showed correlations with mental status and biomarkers.
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Background: Studies that assess cognition prospectively and study in detail anxiety history in the participants' medical records within the context of brain aging and Alzheimer's disease are limited.

Objective: To examine the associations of anxiety and unspecified emotional distress (UED) acquired throughout a person's life with prospectively collected cognitive outcomes.

Methods: Mayo Clinic Study of Aging participants who were cognitively unimpaired at baseline were included.

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Background: Conventional normative samples include individuals with undetected Alzheimer's disease neuropathology, lowering test sensitivity for cognitive impairment.

Objective: We developed Mayo Normative Studies (MNS) norms limited to individuals without elevated amyloid or neurodegeneration (A-N-) for Rey's Auditory Verbal Learning Test (AVLT). We compared these MNS A-N- norms in female, male, and total samples to conventional MNS norms with varying levels of demographic adjustments.

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Objective: To evaluate the performance of Alzheimer disease (AD) cerebrospinal fluid (CSF) biomarkers in a tertiary neurology clinic setting with high frequency of non-AD cases, including normal pressure hydrocephalus (NPH).

Methods: There were 534 patients who underwent AD CSF biomarkers (Roche Elecsys Aβ42, p-Tau181, total-Tau) from April 1, 2020, through April 23, 2021. A behavioral neurologist blinded to CSF results assigned a clinical diagnosis retrospectively on the basis of consensus criteria, and a neuroradiologist blinded to the diagnosis and CSF studies graded brain magnetic resonance images for indicators of CSF dynamics disorders.

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Background: Frontotemporal lobar degeneration (FTLD) is a leading cause of dementia in individuals aged <65 years. Several challenges to conducting in-person evaluations in FTLD illustrate an urgent need to develop remote, accessible, and low-burden assessment techniques. Studies of unobtrusive monitoring of at-home computer use in older adults with mild cognitive impairment show that declining function is reflected in reduced computer use; however, associations with smartphone use are unknown.

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In a previous study, we observed decreased 1,25-dihydroxyvitamin D levels, secondary hyperparathyroidism, and increased bone turnover markers in living kidney donors (LKDs) at 3 months and 36 months after kidney donation. In our recent survey-based study, we found no increased risk of fractures of all types but observed significantly more vertebral fractures in LKDs compared with matched controls. To elucidate the long-term effects of kidney donation on bone health, we recruited 139 LKDs and 139 age and sex matched controls from the survey-based participants for further mechanistic analyses.

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The pathophysiological mechanisms driving disease progression of frontotemporal lobar degeneration (FTLD) and corresponding biomarkers are not fully understood. We leveraged aptamer-based proteomics (> 4,000 proteins) to identify dysregulated communities of co-expressed cerebrospinal fluid proteins in 116 adults carrying autosomal dominant FTLD mutations () compared to 39 noncarrier controls. Network analysis identified 31 protein co-expression modules.

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Article Synopsis
  • Frontotemporal lobar degeneration (FTLD) is a rare condition characterized by behavioral and motor symptoms, making traditional neuropsychological assessments less effective for early detection; smartphone-based cognitive tests may provide a solution for remote evaluations.
  • A study conducted over four years involved 360 participants with varying stages of FTLD using smartphone apps to assess cognitive function, splitting them into discovery and validation groups, with a majority being asymptomatic or at preclinical stages.
  • Results indicate the smartphone-based tests showed moderate to excellent reliability in measuring cognitive function, suggesting they could serve as valid tools for remote assessments in FTLD patients.
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Background: Primary progressive aphasia (PPA) defines a group of neurodegenerative disorders characterised by language decline. Three PPA variants correlate with distinct underlying pathologies: semantic variant PPA (svPPA) with transactive response DNA-binding protein of 43 kD (TDP-43) proteinopathy, agrammatic variant PPA (agPPA) with tau deposition and logopenic variant PPA (lvPPA) with Alzheimer's disease (AD). Our objectives were to differentiate PPA variants using clinical and neuroimaging features, assess progression and evaluate structural MRI and a novel 18-F fluorodeoxyglucose positron emission tomography (FDG-PET) image decomposition machine learning algorithm for neuropathology prediction.

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Importance: Living kidney donors may have an increased risk of fractures due to reductions in kidney mass, lower concentrations of serum 1,25-dihydroxyvitamin D, and secondary increases in serum parathyroid hormone.

Objective: To compare the overall and site-specific risk of fractures among living kidney donors with strictly matched controls from the general population who would have been eligible to donate a kidney but did not do so.

Design, Setting, And Participants: This survey study was conducted between December 1, 2021, and July 31, 2023.

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  • The study analyzed 1,738 participants aged 50 and older from the Mayo Clinic Study of Aging, focusing on the relationship between cerebrovascular imaging markers and mental health indicators.
  • It found that a high burden of white matter hyperintensities (WMH) was significantly linked to increased depression and anxiety scores among participants.
  • Additionally, both cerebrovascular biomarkers and mental health issues were independently associated with an increased likelihood of mild cognitive impairment (MCI).
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Objective: Normative neuropsychological data are essential for interpretation of test performance in the context of demographic factors. The Mayo Normative Studies (MNS) aim to provide updated normative data for neuropsychological measures administered in the Mayo Clinic Study of Aging (MCSA), a population-based study of aging that randomly samples residents of Olmsted County, Minnesota, from age- and sex-stratified groups. We examined demographic effects on neuropsychological measures and validated the regression-based norms in comparison to existing normative data developed in a similar sample.

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Background: Severe adolescent idiopathic scoliosis (AIS) can be treated with instrumented fusion, but the number of anchors needed for optimal correction is controversial.

Methods: We conducted a multicenter, randomized study that included patients undergoing spinal fusion for single thoracic curves between 45° and 65°, the most common form of operatively treated AIS. Of the 211 patients randomized, 108 were assigned to a high-density screw pattern and 103, to a low-density screw pattern.

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Brain imaging research studies increasingly use "de-facing" software to remove or replace facial imagery before public data sharing. Several works have studied the effects of de-facing software on brain imaging biomarkers by directly comparing automated measurements from unmodified vs de-faced images, but most research brain images are used in analyses of correlations with cognitive measurements or clinical statuses, and the effects of de-facing on these types of imaging-to-cognition correlations has not been measured. In this work, we focused on brain imaging measures of amyloid (A), tau (T), neurodegeneration (N), and vascular (V) measures used in Alzheimer's Disease (AD) research.

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Article Synopsis
  • Treatment options for Alzheimer’s disease (AD) are mainly symptomatic, but recent approval of anti-β-amyloid antibodies like lecanemab and aducanumab offers new approaches for early-stage AD.
  • * The study aimed to evaluate how well the clinical trial eligibility criteria for these treatments apply to participants from the Mayo Clinic Study of Aging, focusing on those with early AD.
  • * Out of 237 participants, applying the lecanemab eligibility reduced this to only 19 eligible candidates, suggesting that strict criteria limit access, while relaxing the criteria could increase eligibility to 17.4% of those with mild cognitive impairment.*
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Introduction: We examined associations between plasma-derived biomarkers of Alzheimer's disease (AD) and neuropsychiatric symptoms (NPS) in community-dwelling older adults.

Methods: Cross-sectional study involving 1005 persons ≥50 years of age (mean 74 years, 564 male, 118 cognitively impaired), who completed plasma-derived biomarker (amyloid beta 42 [Aβ42]/Aβ40, phosphorylated tau 181 [p-tau181], p-tau217, total tau [t-tau], neurofilament light [NfL]), and NPS assessment.

Results: P-tau181 (odds ratio [OR] 2.

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Objective: The Stricker Learning Span (SLS) is a computer-adaptive digital word list memory test specifically designed for remote assessment and self-administration on a web-based multi-device platform (Mayo Test Drive). We aimed to establish criterion validity of the SLS by comparing its ability to differentiate biomarker-defined groups to the person-administered Rey's Auditory Verbal Learning Test (AVLT).

Method: Participants ( = 353; mean age = 71, SD = 11; 93% cognitively unimpaired [CU]) completed the AVLT during an in-person visit, the SLS remotely (within 3 months) and had brain amyloid and tau PET scans available (within 3 years).

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