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.

The Accuracy and Reliability of Sleep Staging and Sleep Biomarkers in Patients with Isolated Rapid Eye Movement Sleep Behavior Disorder.

Purpose: This study aimed to establish the diagnostic accuracy of a previously validated sleep staging system in patients with probable isolated REM sleep behavior disorder (iRBD), and to compare physicians' diagnoses of iRBD based on REM sleep without atonia (RSWA) to non-REM hypertonia (NRH), a sleep measure independently associated with Parkinsonian spectrum disorders.

Patients And Methods: Twenty-six patients with a history of dream enactment behavior underwent a diagnostic PSG with simultaneous Sleep Profiler (SP) acquisition at two sites. PSG and SP records were sleep staged, and two sleep neurologists independently diagnosed iRBD based on the presence or absence of polysomnographic identified RSWA.

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).

Sleep Architecture in Response to a Late Evening Competition in Team-Sport Athletes.

Purpose: The aim of this study was to assess the effect of a late evening competition on sleep characteristics and perceived recovery in team-sport players using a validated self-applicable and portable polysomnographic device.

Methods: Sixteen team-sport players (age: 25.4 [1.

Criteria for oral appliance and/or supine avoidance therapy selection based on outcome optimization and cost-effectiveness.

Aim: Produce empirical support for further enhancements to a therapy selection protocol for obstructive sleep apnea (OSA) patients intolerant of positive airway pressure.

Methods: A retrospective analysis was conducted in 101 men and 69 women patients. Two-night home sleep apnea studies were conducted at baseline and with a trial oral appliance.

A comparison between auto-scored apnea-hypopnea index and oxygen desaturation index in the characterization of positional obstructive sleep apnea.

Objective: Evaluate the concordance between overall and positional oxygen desaturation indices (ODI) and apnea-hypopnea indices (AHI) according to two different definitions for positional obstructive sleep apnea (POSA).

Methods: A total of 184 in-home polysomnograms were edited to simulate Level III home sleep apnea tests (HSAT) with the auto-scored AHI and ODI based on recording time. POSA was determined using 132 records with an AHI≥5 and at least 20 mins of recording time in both supine and non-supine positions.

Effects of deep sedation on sleep in critically ill medical patients on mechanical ventilation.

Atypical EEG patterns not consistent with standard sleep staging criteria have been observed in medical intensive care unit (ICU) patients. Our aim was to examine the relationship between sleep architecture and sedation in critically ill mechanically ventilated patients pre- and post-extubation. We performed a prospective observational repeated measures study where 50 mechanically ventilated patients with 31 paired analyses were examined at an academic medical centre.

Head Position During Sleep: Potential Implications for Patients with Neurodegenerative Disease.

Background: The characterization of sleep in those with neurodegenerative disease (NDD) is essential in understanding the potential neurobiological mechanisms that underlie the connection between sleep disruption and NDD manifestations and progression.

Objective: Explore the inter-relationships between NDD and age, sex, diagnosis of obstructive sleep apnea, snoring, and duration of sleep time with the head in the supine and non-supine positions.

Methods: A case-control design was used to evaluate differences in sleep position obtained from multi-night, in-home Sleep Profiler recordings in 45 patients with diagnosed NDD (24 with mild cognitive impairment, 15 with Alzheimer's disease, and 6 with Lewy Body, Parkinson's, or other dementias) and 120 age-sex matched controls with normal cognition (NC).

Comparison of EMG power during sleep from the submental and frontalis muscles.

Objective: Submentalis electromyography (EMG) and frontalis electromyography (EMG) muscle activities have been used to assist in the staging of sleep and detection of disruptions in sleep. This study was designed to assess the concordance between EMG and EMG power, by and across sleep stages.

Methods: Forty-three records with simultaneous acquisition of differential signals from the submental and frontalis muscles were evaluated.

The Accuracy, Night-to-Night Variability, and Stability of Frontopolar Sleep Electroencephalography Biomarkers.

Study Objectives: To assess the validity of sleep architecture and sleep continuity biomarkers obtained from a portable, multichannel forehead electroencephalography (EEG) recorder.

Methods: Forty-seven subjects simultaneously underwent polysomnography (PSG) while wearing a multichannel frontopolar EEG recording device (Sleep Profiler). The PSG recordings independently staged by 5 registered polysomnographic technologists were compared for agreement with the autoscored sleep EEG before and after expert review.

User Compliance and Behavioral Adaptation Associated With Supine Avoidance Therapy.

This study investigates behavioral adaptation to vibrotactile position-avoidance therapy during sleep in patients with obstructive sleep apnea (n =135) across 15 to 52 weeks. The overall compliance, based on nights used ≥ 4 hr, was 71%. Overall regular use, that is, ≥ 4 hr/night over 70% of nights, was 88%.

Modeling temporal sequences of cognitive state changes based on a combination of EEG-engagement, EEG-workload, and heart rate metrics.

The objective of this study was to investigate the feasibility of physiological metrics such as ECG-derived heart rate and EEG-derived cognitive workload and engagement as potential predictors of performance on different training tasks. An unsupervised approach based on self-organizing neural network (NN) was utilized to model cognitive state changes over time. The feature vector comprised EEG-engagement, EEG-workload, and heart rate metrics, all self-normalized to account for individual differences.

Assessment of a neck-based treatment and monitoring device for positional obstructive sleep apnea.

Study Objectives: A majority of patients diagnosed with obstructive sleep apnea are position dependent whereby they are at least twice as severe when sleeping supine (POSA). This study evaluated the accuracy and efficacy of a neck-worn device designed to limit supine sleep. The study included nightly measurements of snoring, sleep/wake, time supine, and the frequency and duration of feedback to monitor compliance.

Capability of a neck worn device to measure sleep/wake, airway position, and differentiate benign snoring from obstructive sleep apnea.

To evaluate the accuracy of a neck-worn device in measuring sleep/wake, detecting supine airway position, and using loud snoring to screen for obstructive sleep apnea. Study A included 20 subjects who wore the neck-device during polysomnography (PSG), with 31 records obtained from diagnostic and split-night studies. Study B included 24 community-based snorers studied in-home for up to three-nights with obstructive sleep apnea (OSA) severity measured with a validated Level III recorder.

Scoring accuracy of automated sleep staging from a bipolar electroocular recording compared to manual scoring by multiple raters.

Objectives: Electroencephalography (EEG) assessment in research and clinical studies is limited by the patient burden of multiple electrodes and the time needed to manually score records. The objective of our study was to investigate the accuracy of an automated sleep-staging algorithm which is based on a single bipolar EEG signal.

Methods: Three raters each manually scored the polysomnographic (PSG) records from 44 patients referred for sleep evaluation.

Retrospective cross-validation of automated sleep staging using electroocular recording in patients with and without sleep disordered breathing.

Background: Alterations of sleep duration and architecture have been associated with increased morbidity and mortality, and specifically linked to chronic cardiovascular disease and psychiatric disorders, such as type 2 diabetes or depression. Measurement of sleep quality to assist in the diagnosis or treatment of these diseases is not routinely performed due to the complexity and cost of conventional methods. The objective of this study is to cross-validate the accuracy of an automated algorithm that stages sleep from the EEG signal acquired with sensors that can be self-applied by patients.

Initial Evaluation of a Titration Appliance for Temporary Treatment of Obstructive Sleep Apnea.

Background: Custom oral appliances that adjustably advance the mandible provide superior outcomes when treating patients with moderate or severe sleep apnea. Custom appliances, however, are expensive, must be fitted by a dentist, and the likelihood of successful outcomes are difficult to predict. An inexpensive trial appliance, if proven efficacious, might be used to predict custom appliance outcomes or to provide temporary therapeutic benefit.

EEG-derived estimators of present and future cognitive performance.

Previous electroencephalography (EEG)-based fatigue-related research primarily focused on the association between concurrent cognitive performance and time-locked physiology. The goal of this study was to investigate the capability of EEG to assess the impact of fatigue on both present and future cognitive performance during a 20-min sustained attention task, the 3-choice active vigilance task (3CVT), that requires subjects to discriminate one primary target from two secondary non-target geometric shapes. The current study demonstrated the ability of EEG to estimate not only present, but also future cognitive performance, utilizing a single, combined reaction time (RT), and accuracy performance metric.

Drowsiness/alertness algorithm development and validation using synchronized EEG and cognitive performance to individualize a generalized model.

A great deal of research over the last century has focused on drowsiness/alertness detection, as fatigue-related physical and cognitive impairments pose a serious risk to public health and safety. Available drowsiness/alertness detection solutions are unsatisfactory for a number of reasons: (1) lack of generalizability, (2) failure to address individual variability in generalized models, and/or (3) lack of a portable, un-tethered application. The current study aimed to address these issues, and determine if an individualized electroencephalography (EEG) based algorithm could be defined to track performance decrements associated with sleep loss, as this is the first step in developing a field deployable drowsiness/alertness detection system.

Patients with positional versus nonpositional obstructive sleep apnea: a retrospective study of risk factors associated with apnea-hypopnea severity.

Objective: The aim of this study was to investigate the differences in and risk factors for positional and nonpositional obstructive sleep apnea (OSA).

Study Design: One hundred twenty-three nonpositional (supine apnea-hypopnea index [AHI] < 2 times the lateral AHI), 218 positional (supine AHI ≥ 2 times the lateral AHI), and 109 age-, gender-, and BMI-matched patients with positional OSA performed 2 nights of sleep study. Gender, age, BMI, and percentage of time in supine position, and percentage of time snoring louder than 40 dB were evaluated as risk factors.

Treatment outcomes of mandibular advancement devices in positional and nonpositional OSA patients.

Objective: The aim of the study was to investigate treatment outcome of mandibular advancement devices (MADs) for positional and nonpositional obstructive sleep apnea (OSA).

Study Design: Forty-two positional (supine apnea-hypopnea index [AHI] > or = 2 times lateral AHI) and 30 nonpositional (supine AHI < 2 times lateral AHI) OSA patients performed 2-nights of sleep study before and after insertion of MADs.

Results: The decreases in apnea severity based on a reduction in the overall and supine AHI values after MADs therapy were significantly greater for the positional OSA than nonpositional OSA group.

The impact of obstructive sleep apnea variability measured in-lab versus in-home on sample size calculations.

Background: When conducting a treatment intervention, it is assumed that variability associated with measurement of the disease can be controlled sufficiently to reasonably assess the outcome. In this study we investigate the variability of Apnea-Hypopnea Index obtained by polysomnography and by in-home portable recording in untreated mild to moderate obstructive sleep apnea (OSA) patients at a four- to six-month interval.

Methods: Thirty-seven adult patients serving as placebo controls underwent a baseline polysomnography and in-home sleep study followed by a second set of studies under the same conditions.