Altered fornix integrity is associated with sleep apnea-related hypoxemia in mild cognitive impairment.

Introduction: The limbic system is critical for memory function and degenerates early in the Alzheimer's disease continuum. Whether obstructive sleep apnea (OSA) is associated with alterations in the limbic white matter tracts remains understudied.

Methods: Polysomnography, neurocognitive assessment, and brain magnetic resonance imaging (MRI) were performed in 126 individuals aged 55-86 years, including 70 cognitively unimpaired participants and 56 participants with mild cognitive impairment (MCI).

Technical challenges in REM sleep microstructure classification: A study of patients with REM sleep behaviour disorder.

While commonly treated as a uniform state in practice, rapid eye movement sleep contains two distinct microstructures-phasic (presence of rapid eye movement) and tonic (no rapid eye movement). This study aims to identify technical challenges during rapid eye movement sleep microstructure visual classification in patients with rapid eye movement sleep behaviour disorder, and to propose solutions to enhance reliability between scorers. Fifty-seven sleep recordings were randomly allocated into three subsequent batches (n = 10, 13 and 34) for scoring.

Nocturnal sleep duration trajectories in early childhood and school performance at age 10 years.

Sleep plays a fundamental role in brain development and resultant functions. The aim was to verify whether nocturnal sleep duration during early childhood has long-term associations with academic achievement at age 10 years. The present study is part of the Quebec Longitudinal Study of Child Development, a representative cohort of infants born in 1997-1998 in the province of Quebec, Canada.

Progression of clinical markers in prodromal Parkinson's disease and dementia with Lewy bodies: a multicentre study.

The neurodegenerative synucleinopathies, including Parkinson's disease and dementia with Lewy bodies, are characterized by a typically lengthy prodromal period of progressive subclinical motor and non-motor manifestations. Among these, idiopathic REM sleep behaviour disorder is a powerful early predictor of eventual phenoconversion, and therefore represents a critical opportunity to intervene with neuroprotective therapy. To inform the design of randomized trials, it is essential to study the natural progression of clinical markers during the prodromal stages of disease in order to establish optimal clinical end points.

Medial temporal lobe and obstructive sleep apnea: Effect of sex, age, cognitive status and free-water.

Medial temporal structures, namely the hippocampus, the entorhinal cortex and the parahippocampal gyrus, are particularly vulnerable to Alzheimer's disease and hypoxemia. Here, we tested the associations between obstructive sleep apnea (OSA) severity and medial temporal lobe volumes in 114 participants aged 55-86 years (35 % women). We also investigated the impact of sex, age, cognitive status, and free-water fraction correction on these associations.

Cardiovascular Risk Factors and Phenoconversion to Neurodegenerative Synucleinopathies in Idiopathic REM Sleep Behavior Disorder.

Several studies have suggested that atherosclerotic diseases and diabetes may be risk factors for α-synucleinopathies. This prospective cohort study evaluated whether cardiovascular diseases and metabolic risk factors alter the rate or type of phenoconversion from idiopathic/isolated REM sleep behavior disorder (iRBD) to parkinsonism or dementia. Polysomnography-confirmed iRBD patients recruited between 2004 and 2020 were followed annually.

Risk Factors for Phenoconversion in Rapid Eye Movement Sleep Behavior Disorder.

Objective: This study was undertaken to follow up predictive factors for α-synuclein-related neurodegenerative diseases in a multicenter cohort of idiopathic/isolated rapid eye movement sleep behavior disorder (iRBD).

Methods: Patients with iRBD from 12 centers underwent a detailed assessment for potential environmental and lifestyle risk factors via a standardized questionnaire at baseline. Patients were then prospectively followed and received assessments for parkinsonism or dementia during follow-up.

Does the adenosine deaminase (ADA) gene confer risk of sleepwalking?

Sleepwalking is a common non-rapid eye movement (NREM) parasomnia and a significant cause of sleep-related injuries. While evidence suggest that the occurrence of this condition is partly determined by genetic factors, its pattern of inheritance remains unclear, and few molecular studies have been conducted. One promising candidate is the adenosine deaminase (ADA) gene.

Rare PSAP Variants and Possible Interaction with GBA in REM Sleep Behavior Disorder.

Background: PSAP encodes saposin C, the co-activator of glucocerebrosidase, encoded by GBA. GBA mutations are associated with idiopathic/isolated REM sleep behavior disorder (iRBD), a prodromal stage of synucleinopathy.

Objective: To examine the role of PSAP mutations in iRBD.

Characterization of Depressive and Anxiety Symptoms in Idiopathic REM Sleep Behavior Disorder.

Background: Depression and anxiety are common in synucleinopathies and often present during prodromal stages, including idiopathic/isolated REM sleep behavior disorder (iRBD). However, the specific profiles of depression/anxiety and their predictive values for phenoconversion remain unclear.

Objective: To assess the predominant manifestations, predictive value, and changes over time in depressive and anxiety symptoms in iRBD.

Novel Associations of and With REM Sleep Behavior Disorder.

Objective: To examine the role of genes identified through genome-wide association studies (GWASs) of Parkinson disease (PD) in the risk of isolated REM sleep behavior disorder (iRBD).

Methods: We fully sequenced 25 genes previously identified in GWASs of PD in a total of 1,039 patients with iRBD and 1,852 controls. The role of rare heterozygous variants in these genes was examined with burden tests.

Comprehensive Analysis of Familial Parkinsonism Genes in Rapid-Eye-Movement Sleep Behavior Disorder.

Background: There is only partial overlap in the genetic background of isolated rapid-eye-movement sleep behavior disorder (iRBD) and Parkinson's disease (PD).

Objective: To examine the role of autosomal dominant and recessive PD or atypical parkinsonism genes in the risk of iRBD.

Methods: Ten genes, comprising the recessive genes PRKN, DJ-1 (PARK7), PINK1, VPS13C, ATP13A2, FBXO7, and PLA2G6 and the dominant genes LRRK2, GCH1, and VPS35, were fully sequenced in 1039 iRBD patients and 1852 controls of European ancestry, followed by association tests.

variants in REM sleep behavior disorder: A multicenter study.

Objective: To study the role of variants in the risk for isolated REM sleep behavior disorder (iRBD) and conversion to overt neurodegeneration.

Methods: A total of 4,147 individuals were included: 1,061 patients with iRBD and 3,086 controls. was fully sequenced using molecular inversion probes and Sanger sequencing.

Pareidolias and cognition in isolated REM sleep behavior disorder.

Background: Though visual illusions and hallucinations are common in dementia with Lewy bodies (DLB) and Parkinson's disease (PD), they are not typically observed clinically in prodromal stages, including isolated REM sleep behavior disorder (iRBD). False-noise errors on the pareidolia test (seeing faces when none are present) may be an effective measure of susceptibility to future hallucinations in iRBD.

Methods: One hundred patients with iRBD underwent the 20-image pareidolia test.

Chronic Neuroleptic-Induced Parkinsonism Examined With Positron Emission Tomography.

Background: Neuroleptic drug-induced parkinsonism (NIP) is a leading cause of parkinsonism, particularly in aging. Based on abnormal dopamine transporter scan results, individuals displaying chronic NIP are often diagnosed with Lewy-body Parkinson's disease (PD), but this assumption needs further substantiation.

Objective: To quantitate the profile of striatal dopaminergic nerve terminal density in NIP relative to PD.

Analysis of common and rare variants in late-onset Parkinson disease.

Objective: We aimed to study the role of coding variants in a large cohort of patients with late-onset Parkinson disease (PD) (LOPD).

Methods: and its untranslated regions were sequenced using targeted next-generation sequencing in 1,567 patients with PD and 1,667 controls from 3 cohorts. Association tests of rare potential homozygous and compound heterozygous variants and burden tests for rare heterozygous variants were performed.

Fine-Mapping of SNCA in Rapid Eye Movement Sleep Behavior Disorder and Overt Synucleinopathies.

Objective: Rapid eye movement sleep behavior disorder (RBD) is a prodromal synucleinopathy, as >80% will eventually convert to overt synucleinopathy. We performed an in-depth analysis of the SNCA locus to identify RBD-specific risk variants.

Methods: Full sequencing and genotyping of SNCA was performed in isolated/idiopathic RBD (iRBD, n = 1,076), Parkinson disease (PD, n = 1,013), dementia with Lewy bodies (DLB, n = 415), and control subjects (n = 6,155).