Comorbid neuropathology and atypical presentation of Alzheimer's disease.

Introduction: Alzheimer's disease (AD) neuropathological changes present with amnestic and nonamnestic (atypical) syndromes. The contribution of comorbid neuropathology as a substratum of atypical expression of AD remains under investigated.

Methods: We examined whether atypical AD exhibited increased comorbid neuropathology compared to typical AD and if such neuropathologies contributed to the accelerated clinical decline in atypical AD.

Livestream, group movement program for people living with cognitive impairment and care partners: A randomized clinical trial.

Introduction: There are few widely-available, evidence-based options to support quality of life (QOL) for people living with Alzheimer's disease and related dementias.

Methods: We performed a randomized, controlled trial with a Waitlist control group to determine whether an online, livestream, mind-body, group movement program (Moving Together, 1 hour, 2 days/week, 12 weeks) improves QOL in people with cognitive impairment (PWCI) or care partners (CPs) and explore mechanisms of action. The primary outcome for both participants was self-reported QOL.

Thresholding approaches for estimating paraspinal muscle fat infiltration using T1- and T2-weighted MRI: Comparative analysis using water-fat MRI.

Background: Paraspinal muscle fat infiltration is associated with spinal degeneration and low back pain, however, quantifying muscle fat using clinical magnetic resonance imaging (MRI) techniques continues to be a challenge. Advanced MRI techniques, including chemical-shift encoding (CSE) based water-fat MRI, enable accurate measurement of muscle fat, but such techniques are not widely available in routine clinical practice.

Methods: To facilitate assessment of paraspinal muscle fat using clinical imaging, we compared four thresholding approaches for estimating muscle fat fraction (FF) using T1- and T2-weighted images, with measurements from water-fat MRI as the ground truth: Gaussian thresholding, Otsu's method, K-mean clustering, and quadratic discriminant analysis.

Participant completion of longitudinal assessments in an online cognitive aging registry: The role of medical conditions.

Introduction: This study aimed to understand whether older adults' longitudinal completion of assessments in an online Alzheimer's disease and related dementias (ADRD)-related registry is influenced by self-reported medical conditions.

Methods: Brain Health Registry (BHR) is an online cognitive aging and ADRD-related research registry that includes longitudinal health and cognitive assessments. Using logistic regressions, we examined associations between longitudinal registry completion outcomes and self-reported (1) number of medical conditions and (2) eight defined medical condition groups (cardiovascular, metabolic, immune system, ADRD, current psychiatric, substance use/abuse, acquired, other specified conditions) in adults aged 55+ ( 23,888).

Variation in skeletal muscle mass among patients with cirrhosis of different self-identified race/ethnicity.

Skeletal muscle index (SMI) remains a strong predictor of mortality in cirrhosis patients. However, the extent to which SMI varies by race/ethnicity has not been fully evaluated. Among 317 patients, 55% identified themselves as non-Hispanic White (NHW), 26% Hispanic White (HW), 13% Asian, and 6% Black.

Bayesian inference of a spectral graph model for brain oscillations.

The relationship between brain functional connectivity and structural connectivity has caught extensive attention of the neuroscience community, commonly inferred using mathematical modeling. Among many modeling approaches, spectral graph model (SGM) is distinctive as it has a closed-form solution of the wide-band frequency spectra of brain oscillations, requiring only global biophysically interpretable parameters. While SGM is parsimonious in parameters, the determination of SGM parameters is non-trivial.

A universal neocortical mask for Centiloid quantification.

Introduction: The Centiloid (CL) project was developed to harmonize the quantification of amyloid beta (Aβ) positron emission tomography (PET) scans to a unified scale. The CL neocortical mask was defined using C Pittsburgh compound B (PiB), overlooking potential differences in regional distribution among Aβ tracers. We created a universal mask using an independent dataset of five Aβ tracers, and investigated its impact on inter-tracer agreement, tracer variability, and group separation.

Safety and tolerability of lumbar puncture for the evaluation of Alzheimer's disease.

Introduction: Lumbar puncture (LP) to collect and examine cerebrospinal fluid (CSF) is an important option for the evaluation of Alzheimer's disease (AD) biomarkers but it is not routinely performed due to its invasiveness and link to adverse effects (AE).

Methods: We include all participants who received at least one LP in the Alzheimer's Disease Neuroimaging Initiative (ADNI) Study. For comparison between groups, two-sample -tests for continuous, and Pearson's chi-square test for categorical variables were performed.

A 1-year randomized controlled trial of a nutritional blend to improve nutritional biomarkers and prevent cognitive decline among community-dwelling older adults: The Nolan Study.

Introduction: This study aimed to test the efficacy of a nutritional blend (NB) in improving nutritional biomarkers and preventing cognitive decline among older adults.

Methods: A 1-year randomized, double-blind, multicenter, placebo-controlled trial with 362 adults (58.6% female, mean 78.

Development and implementation of an electronic Clinical Dementia Rating and Financial Capacity Instrument-Short Form.

Introduction: To address the need for remote assessments of cognitive decline and dementia, we developed and administered electronic versions of the Clinical Dementia Rating (CDR®) and the Financial Capacity Instrument-Short Form (FCI-SF) (F-CAP), called the eCDR and eFCI, respectively.

Methods: The CDR and FCI-SF were adapted for remote, unsupervised, online use based on item response analysis of the standard instruments. Participants completed the eCDR and eFCI first in clinic, and then at home within 2 weeks.

Automatic detection and voxel-wise mapping of lumbar spine Modic changes with deep learning.

Background: Modic changes (MCs) are the most prevalent classification system for describing magnetic resonance imaging (MRI) signal intensity changes in the vertebrae. However, there is a growing need for novel quantitative and standardized methods of characterizing these anomalies, particularly for lesions of transitional or mixed nature, due to the lack of conclusive evidence of their associations with low back pain. This retrospective imaging study aims to develop an interpretable deep learning-based detection tool for voxel-wise mapping of MCs.

Comparison of plasma and CSF biomarkers across ethnoracial groups in the ADNI.

Introduction: Ethnoracial differences in cerebrospinal fluid (CSF; amyloid beta 42 [Aβ42], total tau [t-tau], phosphorylated tau 181 [p-tau181], and plasma (p-tau181, neurofilament light [NfL]) biomarkers of Alzheimer's disease (AD) are incompletely understood.

Methods: We performed cross-sectional analyses with and without adjustment for covariates comparing baseline CSF (Aβ42, t-tau, p-tau181) and plasma (p-tau181, NfL) values in 47 African Americans (AAs) matched to 141 non-Hispanic Whites (NHWs) and 43 Latinos (LAs) matched to 129 NHWs from the Alzheimer's Disease Neuroimaging Initiative (ADNI).

Results: Unadjusted comparisons revealed no significant differences in plasma or CSF biomarkers between AAs and NHWs.

Machine learning approaches to predicting amyloid status using data from an online research and recruitment registry: The Brain Health Registry.

Introduction: This study investigated the extent to which subjective and objective data from an online registry can be analyzed using machine learning methodologies to predict the current brain amyloid beta (Aβ) status of registry participants.

Methods: We developed and optimized machine learning models using data from up to 664 registry participants. Models were assessed on their ability to predict Aβ positivity using the results of positron emission tomography as ground truth.

Dutch Brain Research Registry for study participant recruitment: Design and first results.

Introduction: The Dutch Brain Research Registry aims to facilitate online recruitment of participants for brain disease studies.

Methods: Registrants were primarily recruited through an online social media campaign. The registration process included a short questionnaire, which was subsequently used in the prescreening process to match participants to studies.

Brain health registry GenePool study: A novel approach to online genetics research.

Introduction: Remote data collection, including the establishment of online registries, is a novel approach to efficiently identify risk for cognitive decline and Alzheimer's disease (AD) in older adults, with growing evidence for feasibility and validity. Addition of genetic data to online registries has the potential to facilitate identification of older adults at risk and to advance the understanding of genetic contributions to AD.

Methods: 573 older adult participants with longitudinal online Brain Health Registry (BHR) data underwent apolipoprotein E (APOE) genotyping using remotely collected saliva samples and a novel, automated Biofluid Collection Management Portal.

Cerebrospinal Fluid-Venous Fistulas: A Systematic Review and Examination of Individual Patient Data.

Background: Spontaneous intracranial hypotension (SIH) is usually caused by a spinal cerebrospinal fluid (CSF) leak. CSF-venous fistula is an underdiagnosed cause of spinal CSF leak, as it is challenging to identify on myelography.

Objective: To review existing literature to summarize common presentations, diagnostic imaging modalities, and current treatment strategies for CSF-venous fistulas.

Fetal Cerebral Oxygenation Is Impaired in Congenital Heart Disease and Shows Variable Response to Maternal Hyperoxia.

Background Impairments in fetal oxygen delivery have been implicated in brain dysmaturation seen in congenital heart disease (CHD), suggesting a role for in utero transplacental oxygen therapy. We applied a novel imaging tool to quantify fetal cerebral oxygenation by measuring T2* decay. We compared T2* in fetuses with CHD with controls with a focus on cardiovascular physiologies (transposition or left-sided obstruction) and described the effect of brief administration of maternal hyperoxia on T2* decay.

Evaluation of a visual interpretation method for tau-PET with F-flortaucipir.

Introduction: Positron emission tomography targeting tau (tau-PET) is a promising diagnostic tool for the identification of Alzheimer's disease (AD). Currently available data rely on quantitative measures, and a visual interpretation method, critical for clinical translation, is needed.

Methods: We developed a visual interpretation method for F-flortaucipir tau-PET and tested it on 274 individuals (cognitively normal controls, patients with mild cognitive impairment [MCI], AD dementia, and non-AD diagnoses).

Symptomatic amyloid-related imaging abnormalities in an APOE ε4/ε4 patient treated with aducanumab.

Introduction: Amyloid-related imaging abnormalities (ARIA) are a common, dose-dependent effect of amyloid-targeting antibodies, strongly associated with the apolipoprotein E (APOE) ε4 allele.

Methods: We describe the clinical course and management of a 66-year-old white male (APOE ε4/ε4) enrolled in an observational study that included amyloid and tau positron emission tomography (PET), who received aducanumab through the ENGAGE clinical trial.

Results: Acute symptoms included headache and encephalopathy, and magnetic resonance imaging revealed ARIA-E and ARIA-H.

Predicting amyloid status using self-report information from an online research and recruitment registry: The Brain Health Registry.

Introduction: This study aimed to predict brain amyloid beta (Aβ) status in older adults using collected information from an online registry focused on cognitive aging.

Methods: Aβ positron emission tomography (PET) was obtained from multiple in-clinic studies. Using logistic regression, we predicted Aβ using self-report variables collected in the Brain Health Registry in 634 participants, as well as a subsample (N = 533) identified as either cognitively unimpaired (CU) or mild cognitive impairment (MCI).

BHA-CS: A novel cognitive composite for Alzheimer's disease and related disorders.

Introduction: Composite scores based on psychometrically rigorous cognitive assessments are well suited for early diagnosis and disease monitoring.

Methods: We developed and cross-validated the Brain Health Assessment-Cognitive Score (BHA-CS), based on a brief computerized battery, in 451 cognitively normal (CN) and 399 cognitively impaired (mild cognitive impairment [MCI] or dementia) older adults. We investigated its long-term reliability and reliable change indices at longitudinal follow-up (N = 340), and the association with amyloid beta (Aβ) burden in the CN subgroup with Aβ positron emission tomography (N = 119).