Publications by authors named "Lon S Schneider"

Article Synopsis
  • Pathological tau isoforms, particularly hyperphosphorylated tau at serine 396, and tau oligomers were found in the retinas of patients with mild cognitive impairment (MCI) and Alzheimer's disease (AD), indicating a potential link between tauopathy and retinal changes.
  • The study analyzed retinal cross-sections from 25 patients with MCI or AD and 16 cognitively normal controls, revealing a significant reduction in retinal ganglion cells (RGCs) and increased signs of cell distress in MCI and AD patients compared to controls.
  • Findings showed that higher amounts of pS396-tau in RGCs were strongly correlated with decreased RGC integrity and related to severity in cognitive decline, suggesting that retinal
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Importance: Black or African American (hereinafter, Black) and Hispanic or Latino/a/x (hereinafter, Latinx) adults are disproportionally affected by Alzheimer disease, but most research studies do not enroll adequate numbers of both of these populations. The Alzheimer's Disease Neuroimaging Initiative-3 (ADNI3) launched a diversity taskforce to pilot a multipronged effort to increase the study inclusion of Black and Latinx older adults.

Objective: To describe and evaluate the culturally informed and community-engaged inclusion efforts to increase the screening and enrollment of Black and Latinx older adults in ADNI3.

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Objective: Understanding the course of individual neuropsychiatric symptoms (NPS) and their relationship with function is important for planning targeted interventions for preventing and delaying functional decline. This study aims to disentangle relative contributions of individual NPS on functional decline.

Methods: Longitudinal study of 9,358 well-characterized participants with baseline diagnoses of Mild Cognitive Impairment or AD in the National Alzheimer's Coordinating Center Uniform Data Set.

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Article Synopsis
  • * Researchers analyzed retinal samples from AD patients (both mild cognitive impairment and dementia) and matched controls, finding significant increases in various tau isoforms, particularly in advanced AD cases.
  • * Strong correlations were identified between specific retinal tau isoforms and brain pathology, indicating that changes in the retina could reflect the severity of cognitive decline and neurodegeneration in AD patients.
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Article Synopsis
  • This study focused on developing composite scores for two new cognitive assessments aimed at early-stage Alzheimer's disease (AD) to evaluate their effectiveness and compare them with traditional measures.
  • Researchers analyzed data from 291 older adults to assess the reliability and validity of the new assessments, utilizing exploratory factor analyses to understand their structure.
  • The findings indicated that the new measures, No Practice Effect (NPE) and Miami Computerized Functional Skills Assessment, have superior psychometric properties and stronger links to AD risk markers, suggesting their potential use in clinical trials for early Alzheimer's detection.
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Article Synopsis
  • - This study investigates the presence of various pathological tau proteins in the retinas of individuals with early and advanced Alzheimer's disease (AD) and their connection to the severity of the disease.
  • - Researchers analyzed retinal and brain samples from 75 donors with conditions ranging from normal cognition to mild cognitive impairment (MCI) and AD, using advanced histopathology and digital profiling methods.
  • - The results showed significant increases in multiple tau isoforms in the retinas of AD and MCI patients compared to normal controls, suggesting a correlation between retinal changes and cognitive decline.
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Background: Per cent slowing of decline is frequently used as a metric of outcome in Alzheimer's disease (AD) clinical trials, but it may be misleading. Our objective was to determine whether per cent slowing of decline or Cohen's d is the more valid and informative measure of efficacy.

Methods: Outcome measures of interest were per cent slowing of decline; Cohen's d effect size and number-needed-to-treat (NNT).

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Objective: Prior studies have reported an association between depression and quality of life (QOL) in Alzheimer's disease (AD), but the effect of self- versus proxy rating of mood and QOL has not been described.

Design: In this secondary analysis of data from a cohort study, the authors used a linear mixed-effects model to determine if the association between depression and QOL is affected by whether both measures are assessed by the same member of the patient-caregiver dyad.

Setting: Participants and caregiver informants were recruited from 10 California Alzheimer Disease Centers.

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Introduction The purpose of this guide is to provide convenient and useful information on about Alzheimer's disease and dementias of late life. The information includes selected facts, diagnostic criteria tables, descriptions of selected tests and screens, guidelines, clinical pharmacological data and references. This guide is divided into several sections: Background factsDiagnostic aids and criteria for dementia diagnosesMedications used for Alzheimer's disease and dementia Basic information on marketed treatments is provided although the treatment may not be FDA approved for this use.

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Article Synopsis
  • - The study addresses the issue of limited ancestral diversity in genome-wide association studies (GWAS), which makes it hard to find genetic risk variants in non-European ancestry groups, focusing on Alzheimer's Disease (AD).
  • - Researchers analyzed a multi-ancestry GWAS dataset within the Alzheimer's Disease Genetics Consortium (ADGC) involving individuals from various ancestries, identifying 13 shared risk loci and 3 ancestry-specific loci, highlighting the benefits of diverse samples.
  • - The findings underscore the importance of including underrepresented populations in genetic research, suggesting that even smaller sample sizes can lead to the discovery of novel genetic variants related to AD and implicating specific biological pathways like amyloid regulation and neuronal development.
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Introduction: Dementia is characterized by significant declines in cognitive, physical, social, and behavioral functioning, and includes multiple subtypes that differ in etiology. There is limited evidence of the influence of psychiatric and substance use history on the risk of dementia subtypes among older underrepresented racial/ethnic minorities in the United States. Our study explored the role of psychiatric and substance use history on the risk of etiology-specific dementias: Alzheimer's disease (AD) and vascular dementia (VaD), in the context of a racially and ethnically diverse sample based on national data.

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Introduction: Restrictions during the COVID-19 pandemic necessitated remote administration of neuropsychological testing. We assessed the test-retest reliability for a telephone-administered cognitive battery, recommended for use in the National Institute on Aging Alzheimer's Disease Research Center (ADRC).

Methods: 64 participants in the University of Southern California ADRC clinical core underwent repeat telephone evaluation using the T-cog Neuropsychological Battery.

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Despite considerable progress in pharmacotherapy over the past seven decades, many mental disorders remain insufficiently treated. This situation is in part due to the limited knowledge of the pathophysiology of these disorders and the lack of biological markers to stratify and individualize patient selection, but also to a still restricted number of mechanisms of action being targeted in monotherapy or combination/augmentation treatment, as well as to a variety of challenges threatening the successful development and testing of new drugs. In this paper, we first provide an overview of the most promising drugs with innovative mechanisms of action that are undergoing phase 2 or 3 testing for schizophrenia, bipolar disorder, major depressive disorder, anxiety and trauma-related disorders, substance use disorders, and dementia.

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Background: In amyloid-positive individuals at risk for Alzheimer's disease (AD), high soluble 42-amino acid amyloid-β (Aβ42) levels are associated with normal cognition. It is unknown if this relationship applies longitudinally in a genetic cohort.

Objective: To test the hypothesis that high Aβ42 preserves normal cognition in amyloid-positive individuals with Alzheimer's disease (AD)-causing mutations (APP, PSEN1, or PSEN2) to a greater extent than lower levels of brain amyloid, cerebrospinal fluid (CSF) phosphorylated tau (p-tau), or total tau (t-tau).

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Observational studies suggest that nutritional factors have a potential cognitive benefit. However, systematic reviews of randomised trials of dietary and nutritional supplements have reported largely null effects on cognitive outcomes and have highlighted study inconsistencies and other limitations. In this Personal View, the Nutrition for Dementia Prevention Working Group presents what we consider to be limitations in the existing nutrition clinical trials for dementia prevention.

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As the prevalence of dementia and Alzheimer's disease (AD) increases worldwide, it is imperative to reflect on the major clinical trials in the prevention of dementia and the challenges that surround them. The pharmaceutical industry has focused on developing drugs that primarily affect the Aβ cascade and tau proteinopathy, while academics have focused on repurposed therapeutics and multi-domain interventions for prevention studies. This paper highlights significant primary, secondary, and tertiary prevention trials for dementia and AD, overall design, methods, and systematic issues to better understand the current landscape of prevention trials.

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We propose the hypothesis that small high-density lipoprotein (HDL) particles reduce the risk of Alzheimer's disease (AD) by virtue of their capacity to exchange lipids, affecting neuronal membrane composition and vascular and synaptic functions. Concentrations of small HDLs in cerebrospinal fluid (CSF) and plasma were measured in 180 individuals ≥60 years of age using ion mobility methodology. Small HDL concentrations in CSF were positively associated with performance in three domains of cognitive function independent of apolipoprotein E (APOE) ε4 status, age, sex, and years of education.

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Introduction: Clinical trials for sporadic Alzheimer's disease generally use mixed models for repeated measures (MMRM) or, to a lesser degree, constrained longitudinal data analysis models (cLDA) as the analysis model with time since baseline as a categorical variable. Inferences using MMRM/cLDA focus on the between-group contrast at the pre-determined, end-of-study assessments, thus are less efficient (eg, less power).

Methods: The proportional cLDA (PcLDA) and proportional MMRM (pMMRM) with time as a categorical variable are proposed to use all the post-baseline data without the linearity assumption on disease progression.

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Introduction: Allopregnanolone (ALLO), an endogenous neurosteroid, promoted neurogenesis and oligogenesis and restored cognitive function in animal models of Alzheimer's disease (AD). Based on these discovery research findings, we conducted a randomized-controlled phase 1b/2a multiple ascending dose trial of ALLO in persons with early AD (NCT02221622) to assess safety, tolerability, and pharmacokinetics. Exploratory imaging outcomes to determine whether ALLO impacted hippocampal structure, white matter integrity, and functional connectivity are reported.

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Background: The COVID-19 pandemic disrupted Alzheimer disease randomized clinical trials (RCTs), forcing investigators to make changes in the conduct of such trials while endeavoring to maintain their validity. Changing ongoing RCTs carries risks for biases and threats to validity. To understand the impact of exigent modifications due to COVID-19, we examined several scenarios in symptomatic and disease modification trials that could be made.

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