Concordance and test-retest consistency of sleep biomarker-based neurodegenerative disorder profiling.

Biomarkers that aid in early detection of neurodegeneration are needed to enable early symptomatic treatment and enable identification of people who may benefit from neuroprotective interventions. Increasing evidence suggests that sleep biomarkers may be useful, given the bi-directional relationship between sleep and neurodegeneration and the prominence of sleep disturbances and altered sleep architectural characteristics in several neurodegenerative disorders. This study aimed to demonstrate that sleep can accurately characterize specific neurodegenerative disorders (NDD).

Curation and validation of electronic medical record-based dementia diagnoses in the VA Million Veteran Program.

Background: The age distribution and diversity of the VA Million Veteran Program (MVP) cohort make it a valuable resource for studying the genetics of Alzheimer's disease (AD) and related dementias (ADRD).

Objective: We present and evaluate the performance of several International Classification of Diseases (ICD) code-based classification algorithms for AD, ADRD, and dementia for use in MVP genetic studies and other studies using VA electronic medical record (EMR) data. These were benchmarked relative to existing ICD algorithms and AD-medication-identified cases.

Missense and loss-of-function variants at GWAS loci in familial Alzheimer's disease.

Background: Few rare variants have been identified in genetic loci from genome-wide association studies (GWAS) of Alzheimer's disease (AD), limiting understanding of mechanisms, risk assessment, and genetic counseling.

Methods: Using genome sequencing data from 197 families in the National Institute on Aging Alzheimer's Disease Family Based Study and 214 Caribbean Hispanic families, we searched for rare coding variants within known GWAS loci from the largest published study.

Results: Eighty-six rare missense or loss-of-function (LoF) variants completely segregated in 17.

Association of CSF α-Synuclein Seeding Amplification Assay Results With Clinical Features of Possible and Probable Dementia With Lewy Bodies.

Background And Objectives: The clinical diagnosis of dementia with Lewy bodies (DLB) depends on identifying significant cognitive decline accompanied by core features of parkinsonism, visual hallucinations, cognitive fluctuations, and REM sleep behavior disorder (RBD). Hyposmia is one of the several supportive features. α-Synuclein seeding amplification assays (αSyn-SAAs) may enhance diagnostic accuracy by detecting pathologic αSyn seeds in CSF.

Missense and Loss of Function Variants at GWAS Loci in Familial Alzheimer's Disease.

Background: Few rare variants have been identified in genetic loci from genome wide association studies of Alzheimer's disease (AD), limiting understanding of mechanisms and risk assessment, and genetic counseling.

Methods: Using genome sequencing data from 197 families in The NIA Alzheimer's Disease Family Based Study, and 214 Caribbean Hispanic families, we searched for rare coding variants within known GWAS loci from the largest published study.

Results: Eighty-six rare missense or loss of function (LoF) variants completely segregated in 17.

Autonomic dysregulation during sleep in Parkinsonian spectrum disorders - A proof of concept.

Introduction: Autonomic dysfunction is common in α-synucleinopathies such as Lewy Body dementias (LBD), Parkinson's disease (PD), and isolated REM Sleep Behavior Disorder (iRBD). We analyzed pulse-rate changes during sleep to index autonomic nervous system (ANS) dysfunction in patients with α-synucleinopathies vs. non-synucleinopathy groups expected to have normal ANS function.

Proof-of-concept for characterization of neurodegenerative disorders utilizing two non-REM sleep biomarkers.

Study Objective: This proof-of-concept study aimed to determine whether the combined features of two non-rapid eye movement (NREM) sleep biomarkers acquired predominantly in-home could characterize different neurodegenerative disorders.

Methods: Sleep spindle duration and non-REM hypertonia (NRH) were evaluated in seven groups including a control group (CG = 61), and participants with isolated REM sleep behavior disorder (iRBD = 19), mild cognitive impairment (MCI = 41), Parkinson disease (PD = 16), Alzheimer disease dementia (ADem = 29), dementia with Lewy Bodies or Parkinson disease dementia (LBD = 19) and progressive supranuclear palsy (PSP = 13). One-way analysis of variance (ANOVA), Mann-Whitney , intra-class (ICC) and Spearman ranked correlations, Bland-Altman plots and Kappa scores, Chi-square and Fisher exact probability test, and multiple-logistic regression were focused primarily on spindle duration and NRH and the frequencies assigned to the four normal/abnormal spindle duration/NRH combinations.

Pimavanserin Treatment for Psychosis in Patients with Dementia with Lewy Bodies: A Case Series.

BACKGROUND Many patients with dementia with Lewy bodies (DLB) experience cholinesterase inhibitor- and antipsychotic-resistant psychosis. The new second-generation antipsychotic pimavanserin has been used with some success in the treatment of psychosis in other forms of dementia, including Alzheimer disease and Parkinson disease dementia. It is possible that pimavanserin may also be useful in the treatment of psychosis in DLB.

ATN cerebrospinal fluid biomarkers in dementia with Lewy bodies: Initial results from the United States Dementia with Lewy Bodies Consortium.

Introduction: The National Institute on Aging - Alzheimer's Association (NIA-AA) ATN research framework proposes to use biomarkers for amyloid (A), tau (T), and neurodegeneration (N) to stage individuals with AD pathological features and track changes longitudinally. The overall aim was to utilize this framework to characterize pre-mortem ATN status longitudinally in a clinically diagnosed cohort of dementia with Lewy bodies (DLB) and to correlate it with the post mortem diagnosis.

Methods: The cohort was subtyped by cerebrospinal fluid (CSF) ATN category.

NOTCH3 C201R variant causes cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) that can be confused with early-onset Alzheimer's disease.

Background: NOTCH3 is the causative gene for autosomal dominant cerebral arteriopathy with subcortical infarctions and leukoencephalopathy (CADASIL) which is associated with both stroke and dementia. When CADASIL presents primarily as dementia it can be difficult to distinguish from Alzheimer's disease (AD) at both the clinical and neuropathological levels.

Methods: We performed exome sequencing of several affected individuals from a large family affected with AD.

A Preliminary Comparison of the Methylome and Transcriptome from the Prefrontal Cortex Across Alzheimer's Disease and Lewy Body Dementia.

Background: Pathological amyloid-β and -synuclein are associated with a spectrum of related dementias, ranging from Alzheimer's disease (AD) and dementia with Lewy bodies (DLB) to Parkinson disease dementia (PDD). While these diseases share clinical and pathological features, they also have unique patterns of pathology. However, epigenetic factors that contribute to these pathological differences remain unknown.

Polygenic risk score penetrance & recurrence risk in familial Alzheimer disease.

Objective: To compute penetrance and recurrence risk using a genome-wide PRS (including and excluding the APOE region) in families with Alzheimer's disease.

Methods: Genotypes from the National Institute on Aging Late-Onset Alzheimer's Disease Family-Based Study and a study of familial Alzheimer's disease in Caribbean Hispanics were used to compute PRS with and without variants in the 2 MB region flanking APOE. PRS was calculated in using clumping/thresholding and Bayesian methods and was assessed for association with Alzheimer's disease and age at onset.

Identifying probable dementia in undiagnosed Black and White Americans using machine learning in Veterans Health Administration electronic health records.

The application of machine learning (ML) tools in electronic health records (EHRs) can help reduce the underdiagnosis of dementia, but models that are not designed to reflect minority population may perpetuate that underdiagnosis. To address the underdiagnosis of dementia in both Black Americans (BAs) and white Americans (WAs), we sought to develop and validate ML models that assign race-specific risk scores. These scores were used to identify undiagnosed dementia in BA and WA Veterans in EHRs.

Correction: Valcic et al. Determining Whether Sex and Zygosity Modulates the Association between APOE4 and Psychosis in a Neuropathologically-Confirmed Alzheimer's Disease Cohort. 2022, , 1266.

In the original publication [...

African ancestry GWAS of dementia in a large military cohort identifies significant risk loci.

While genome wide association studies (GWASs) of Alzheimer's Disease (AD) in European (EUR) ancestry cohorts have identified approximately 83 potentially independent AD risk loci, progress in non-European populations has lagged. In this study, data from the Million Veteran Program (MVP), a biobank which includes genetic data from more than 650,000 US Veteran participants, was used to examine dementia genetics in an African descent (AFR) cohort. A GWAS of Alzheimer's disease and related dementias (ADRD), an expanded AD phenotype including dementias such as vascular and non-specific dementia that included 4012 cases and 18,435 controls age 60+ in AFR MVP participants was performed.

Sex Modifies the Associations of APOEɛ4 with Neuropsychiatric Symptom Burden in Both At-Risk and Clinical Cohorts of Alzheimer's Disease.

Background: Recent work suggests that APOEɛ4/4 females with Alzheimer's disease (AD) are more susceptible to developing neuropsychiatric symptoms (NPS).

Objective: To examine the interaction of sex and APOEɛ4 status on NPS burden using two independent cohorts: 1) patients at risk for AD with mild cognitive impairment and/or major depressive disorder (n = 252) and 2) patients with probable AD (n = 7,261).

Methods: Regression models examined the interactive effects of sex and APOEɛ4 on the number of NPS experienced and NPS Severity.

Non-REM sleep with hypertonia in Parkinsonian Spectrum Disorders: A pilot investigation.

Introduction: From an ongoing multicenter effort toward differentiation of Parkinsonian spectrum disorders (PSD) from other types of neurodegenerative disorders, the sleep biomarker non-rapid-eye-movement sleep with hypertonia (NRH) emerged.

Methods: This study included in the PSD group patients with dementia with Lewy bodies/Parkinson disease dementia (DLB/PDD = 16), Parkinson disease (PD = 16), and progressive supranuclear palsy (PSP = 13). The non-PSD group included patients with Alzheimer disease dementia (AD = 24), mild cognitive impairment (MCI = 35), and a control group with normal cognition (CG = 61).

Determining Whether Sex and Zygosity Modulates the Association between APOE4 and Psychosis in a Neuropathologically-Confirmed Alzheimer's Disease Cohort.

Background: The APOE4 allele is a genetic risk factor for developing late-onset Alzheimer's disease (AD). Previous work by our group revealed that female APOE4 homozygotes with Lewy body (LB) pathology were more likely to experience psychosis compared to female APOE4 non-carriers, whereas in males there was no APOE4 dose-dependent significant effect. The objective of this study was to refine our previous findings by adjusting for covariates and determining the probability of an APOE4 sex-mediated effect on psychosis.

Homozygous CADPS2 Mutations Cause Neurodegenerative Disease with Lewy Body-like Pathology in Parrots.

Background: Several genetic models that recapitulate neurodegenerative features of Parkinson's disease (PD) exist, which have been largely based on genes discovered in monogenic PD families. However, spontaneous genetic mutations have not been linked to the pathological hallmarks of PD in non-human vertebrates.

Objective: To describe the genetic and pathological findings of three Yellow-crowned parrot (Amazona ochrocepahala) siblings with a severe and rapidly progressive neurological phenotype.

Correlates of Conversion from Mild Cognitive Impairment to Dementia with Lewy Bodies: Data from the National Alzheimer's Coordinating Center.

Background: Many patients with dementia with Lewy bodies (DLB) miss out on the best standards of care and psychosocial support due to diagnostic delays or inaccuracies following symptom onset.

Objective: This study seeks to identify baseline characteristics in individuals with mild cognitive impairment (MCI) that correlate with eventual conversion to DLB or Alzheimer's disease (AD).

Methods: Baseline neuropsychological and neuropsychiatric data were analyzed in National Alzheimer's Coordinating Center participants who completed the Uniform Data Set between 2006 and 2020 and subsequently converted from MCI to DLB or AD (n = 1632).

The National Institute on Aging Late-Onset Alzheimer's Disease Family Based Study: A resource for genetic discovery.

Introduction: The National Institute on Aging Late-Onset Alzheimer's Disease Family Based Study (NIA-LOAD FBS) was established to study the genetic etiology of Alzheimer's disease (AD).

Methods: Recruitment focused on families with two living affected siblings and a third first-degree relative similar in age with or without dementia. Uniform assessments were completed, DNA was obtained, as was neuropathology, when possible.