Polysomnographic Study Research Articles

Sleep in the dromedary camel: features of the 'first night effect'.

The 'first night effect' (FNE) is a well-known phenomenon in polysomnographic (PSG) sleep studies, resulting in significant variations in the macrostructure of wakefulness and sleep states, particularly between the initial and subsequent sleep recording sessions. The FNE phenomenon during sleep has been studied in various species, revealing complex variations between several sessions of sleep recording. The present study used a non-invasive PSG method to examine differences between various vigilance states in four adult female dromedary camels during 4 consecutive nights and days of sleep recording. The results indicate the presence of a FNE in the architecture of the dromedary camel's vigilance states. On the first night, the proportions of wakefulness and light non-rapid eye movment (NREM) sleep (drowsiness) were higher, at a mean (standard error of the mean [SEM]) of 40.92% (0.88%) and 14.93% (0.37%), respectively; while the proportion of rumination (mean [SEM] 29.55% [0.92%]) was lower compared to consecutive nights. No FNE was found on deep NREM sleep, while night-time REM sleep had a shorter proportion during the first night compared to subsequent consecutive nights. A significantly lower REM/total sleep time (TST) ratio was observed on the first night. Daytime comparisons did not show any significant differences for the different vigilance states. The increase in wakefulness and light NREM sleep and the reduction in REM sleep and REM/TST sleep on the first night indicate a decline in sleep quality in the dromedary camel due to the FNE. Thus, we recommend excluding from a PSG sleep study at least the first session/night of the recordings to ensure accurate results.

Utility of cardiac implantable electronic device algorithm for detecting severe sleep‐disordered breathing in cardiomyopathy

AbstractBackgroundHalf of patients with heart failure are estimated to have sleep‐disordered breathing (SDB). However, many are undiagnosed as they do not report typical symptoms. This study aims to evaluate the implantable cardiac defibrillator (ICD) sleep‐disordered breathing algorithm in a cohort of multi‐racial Asian patients for detection of SDB against polysomnography (PSG).MethodsIn this prospective pilot study, participants who fulfill the American College of Cardiology (ACC) indication for ICD were recruited. The ICD algorithm uses transthoracic impedance sensing to calculate respiratory disturbance index (RDI).ResultsTwenty‐four patients were enrolled between August 2020 and December 2021. All patients underwent PSG exams and were followed up for up to 12 months. Eighteen participants completed the PSG study as of August 23, 2022. Severe SDB (defined as PSG‐AHI ≥30 episodes/h) was diagnosed in 66.7% of the patients. No significant direct linear correlation was found between the PSG‐AHI measurements and the RDI measurements (adjusted r2 = .224, r = .473, p = .027). Applying a binary threshold cut‐off RDI value of 32 episodes/h for the detection of severe SDB yielded a sensitivity of 91.7% and specificity of 16.7%.ConclusionsTransthoracic impedance sensing with an advanced inbuilt algorithm may be helpful as a screening test in detecting severe SDB in patients with heart failure and cardiomyopathy, potentially by applying a binary threshold cut‐off value. This is the first study known to validate the algorithm in an exclusively multi‐ethnic Asian population with heart failure.

Polysomnographic insights into the attention-deficit/hyperactivity disorder and obstructive sleep apnea connection in children

IntroductionThere is a high prevalence of sleep disturbances and disorders such as obstructive sleep apnea (OSA) in children with attention-deficit hyperactivity disorder (ADHD), though this relationship remains poorly characterized by objective measures. Polysomnographic studies (PSGs) on sleep disruptions in ADHD have yielded inconsistent results. Few have studied polysomnograms in stimulant-medicated vs. non-medicated children with ADHD+/-OSA. This study aimed to elucidate pathognomonic polysomnographic sleep disturbances in children diagnosed with ADHD+/-OSA.MethodsMedical charts and polysomnograms were retrospectively reviewed for children ages 4-18 who underwent overnight polysomnography at a tertiary care center from 2019 to 2022. ADHD diagnosis was determined by ICD code F90, and OSA was defined by apnea-hypopnea indices (AHI) ≥5 events/hour. Four groups were evaluated: children without OSA or ADHD, children with OSA alone, children with ADHD alone, and children with ADHD+OSA. Statistical analyses identified significant differences among variables of interest.Results4,013 children met the study criteria. 2,372 children were without OSA and without ADHD (59.1%), 1,197 with OSA alone (29.8%), 333 with ADHD alone (8.3%), and 111 with ADHD and OSA (2.8%). Insomnia (ICD code G47.00) was prevalent in children with ADHD alone. However, they exhibited significantly better sleep efficiency (SE), than children with OSA alone, and SE did not significantly differ from the other groups. No significant difference in periodic limb movements (PLMs) was found across all groups. The above results held true even after correcting for stimulant prescription.ConclusionThe increased frequency of clinical insomnia diagnoses in children with ADHD is not associated with any traditional parameters on polysomnogram. Innovative subclinical polysomnographic biomarkers are needed to identify sleep characteristics unique to ADHD. In children with both ADHD and OSA, PSG results do not reveal any distinctive sleep disturbances which cannot be better explained by OSA alone. These findings underscore the importance of screening for OSA in patients with ADHD and clinically assessing for other sleep concerns.

A study of sleep disorders in Indian children: Tip of the iceberg

BackgroundInsufficient quality and quantity of sleep has dangerous neurodevelopmental outcomes in the form of poor concentration, poor scholastic performance, hyperactivity and obstructive sleep apnea. There is no structured data on prevalence of various sleep behaviours and sleep related disorders in children in India. We aim to study sleep behaviour of children to know the common paediatric sleep related disorders. MethodsWe enrolled 270 children between the age of 1 to 18 years visiting pediatric OPDs for minor ailments between June 2022 to June 2023 using Children Sleep habit questionnaire – (NICHD SECCYD, Wisconsin). Children having clinical features suggestive of obstructive sleep apnoea were further subjected to overnight level 1 Polysomnography study. ResultsMost children had bed time consistency with average sleep duration of Mean ± 2SD (8.58 ± 1.35 h, N=270), which was shorter than global average. Allergic disorders were significantly high with prevalence of allergic rhinitis up to 30 % and asthma between 8-10 % in our study. Prevalence of obstructive sleep apnea on Polysomnography study was 5.6%, parent reported snoring 10 %, restless leg movements 30% and open mouth breathing in 35% Indian children. In our study, Asthma had statistically significant association with sleep disordered breathing and obstructive sleep apnea with p value < 0.01. ConclusionsAsthma has statistically significant association with obstructive sleep apnoea in our study. Proper asthma treatment may reduce the burden of obstructive sleep apnoea in children. There is a growing need to screen children regularly for sleep related issues on routine visits.

Pentraxin-3 marker as a predictor of cardiovascular events in obstructive sleep apnea; a cross-sectional study

Introduction A large population suffers from obstructive sleep apnea (OSA). Most of these individuals (almost 90%) are either unrecognized or untreated OSA. These patients are at increased risk of cardiovascular diseases. Aim The aim of this study was to assess the prognostic value of Pentraxin 3 (PTX3) in OSA compared with the clinically relevant biological markers (HbA1c, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), uric acid, and fibrinogen) and to evaluate the relationship between PTX3 levels and risk of cardiovascular diseases. Patients and methods This research used a cross-sectional design and enrolled 100 participants with suspected OSA. All the participants underwent a full clinical history, a STOP-Bang questionnaire, and a polysomnography (PSG) study, and the serum biomarkers were also analyzed. Results The apnea-hypopnea index (AHI) from PSG was used to measure the OSA severity, and the individuals were distributed into three groups accordingly. Our findings showed that there was a significant difference in Pentraxin 3 and fibrinogen levels between patients with mild or moderate OSA and those with severe OSA. Pentraxin 3, at a cutoff point of greater than 4.25 ng/ml, had the highest prognostic accuracy in OSA (96%), with an AUC of 0.96. Regression analysis revealed that Pentraxin 3, with a cutoff point greater than 4.25, and CRP were significant predictors of cardiovascular disease in individuals with OSA. Furthermore, Pentraxin 3 (with a cutoff point of greater than 4.25 ng/ml) and fibrinogen were significant predictors of pulmonary embolism in patients with OSA. Conclusion Serum PTX3 was higher in patients with severe OSA than in those with mild- to moderate OSA. Furthermore, we found that OSA severity as indicated by the AHI was significantly correlated with serum PTX3. PTX3 and CRP are useful markers of cardiovascular risk in OSA.

Density Spectral Array EEG for Sleep Staging in Pediatric Patients.

Sleep is an essential physiologic process, which is frequently disrupted in children with illness and/or injury. Accurate identification and quantification of sleep may provide insights to improve long-term clinical outcomes. Traditionally, however, the identification of sleep stages has relied on the resource-intensive and time-consuming gold standard polysomnogram. We sought to use limited EEG data, converted into density spectrum array EEG, to accurately identify sleep stages in a clinical pediatric population. We reviewed 87 clinically indicated pediatric polysomnographic studies with concurrent full montage EEG, between March 2017 and June 2020, of which 11 had normal polysomnogram and EEG interpretations. We then converted the EEG data of those normal studies into density spectral array EEG trends and had five blinded raters classify sleep stage (wakefulness, nonrapid eye movement [NREM] 1, NREM 2, NREM 3, and rapid eye movement) in 5-minute epochs. We compared the classified sleep stages from density spectral array EEG to the gold standard polysomnogram. Inter-rater reliability was highest (κ = 0.745, P < 0.0001) when classifying state into wakefulness, NREM sleep, and rapid eye movement sleep. Agreement between group classification and polysomnogram was highest (κ = 0.873, [0.819, 0.926], P < 0.0001) when state was classified into wakefulness and sleep and was lowest (κ = 0.674 [0.645, 0.703], P < 0.0001) when classified into wakefulness, NREM 1, NREM 2, NREM 3, and rapid eye movement. The most common error that raters made was overscoring of NREM 1. Density spectral array EEG can be used to identify sleep stages in clinical pediatric patients without relying on traditional polysomnography.

Effect of exercise versus mandibular advancement device in moderate obstructive sleep apnea patients with mandibular retrognathia: A randomized clinical trial

ABSTRACT Objective The aim of this study was to investigate the effects of exercise and mandibular advancement device (MAD) on severity of Obstructive sleep apnea syndrome (OSAS) with mandibular retrognathia. Methods Patients were randomly allocated into either exercise group or MAD group. All patients underwent blood tests, polysomnography studies and questionnaires studies at enrollment and at the 12-week’s follow-up. Results Our study showed MAD was superior to exercise in improving polysomnographic outcomes and Snore Scale (SS) score. No significant difference was observed between the two treatments in terms of Epworth Sleepiness Scale (ESS) score. Moreover, in the exercise group, improvements were also observed in total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C). Conclusion MAD was more effective than exercise in improving sleep efficiency. Exercise can improve daytime sleepiness and lipid metabolism, independent of the effects on BMI. Trial registration ChiCTR2000034188

Exploring Sleep Architecture in Polish Patients with Multiple Sclerosis: A Polysomnography Study.

Sleep disturbances are a prevalent phenomenon in patients with multiple sclerosis (PwMS). The present study employs polysomnography (PSG) to quantify sleep efficiency and architecture in PwMS, aiming to elucidate the relationships between PSG parameters and factors including gender, disability level, brain lesion location, and subjective measures of insomnia, excessive daytime sleepiness (EDS), fatigue, pain, and mood disorders. The study cohort comprised 51 adult PwMS, of whom 31 underwent overnight PSG. The demographic and clinical characteristics, including age, gender, and Expanded Disability Status Scale (EDSS), were collated. The Athens Insomnia Scale, the Epworth Sleepiness Scale, the Fatigue Severity Scale, the Modified Fatigue Impact Scale (MFIS), the Numerical Pain Rating Scale, and the Hospital Anxiety and Depression Scale were employed for the assessment of insomnia, EDS, fatigue, pain, and mood disorders. The brain and spinal cord magnetic resonance imaging (MRI) were evaluated. A reduced sleep efficiency was observed among 30 PwMS (aged 38.9 ± 12.9), with a mean of 80 ± 12%, especially in those with brainstem demyelinating lesions. In those PwMS aberrant sleep onset latency (SOL) and wake after sleep onset were also noted (p < 0.05). The prevalence of sleep fragmentation, as measured by the total arousal index, was greater in male PwMS than in female (p < 0.05). Higher disability according to the EDSS correlated with longer SOL (ρ = 0.48, p < 0.05), and reduced N2 sleep stage correlated with cognitive fatigue according to MFIS (ρ = -0.46, p < 0.05). Age, disease duration, insomnia, EDS, physical fatigue, and mood disorders did not impact PSG parameters. The study demonstrated the disruption of sleep architecture in PwMS, and highlighted the importance of a comprehensive PSG assessment of sleep disturbances in this population.

Morphological Prediction of CPAP Associated Acute Respiratory Instability.

Multiple mechanisms are involved in the pathogenesis of obstructive sleep apnea (OSA). Elevated loop gain is a key target for precision OSA care and may be associated with treatment intolerance when the upper airway is the sole therapeutic target. Morphological or computational estimation of LG is not yet widely available or fully validated - there is a need for improved phenotyping/endotyping of apnea to advance its therapy and prognosis. This study proposes a new algorithm to assess self-similarity as a signature of elevated loop gain using respiratory effort signals and presents its use to predict the probability of acute failure (high residual event counts) of continuous positive airway pressure (CPAP) therapy. Effort signals from 2145 split-night polysomnography studies from the Massachusetts General Hospital were analyzed for SS and used to predict acute CPAP therapy effectiveness. Logistic regression models were trained and evaluated using 5-fold cross-validation. Receiver operating characteristic (ROC) and precision-recall (PR) curves with AUC values of 0.82 and 0.84, respectively, were obtained. Self-similarity combined with the central apnea index (CAI) and hypoxic burden outperformed CAI alone. Even in those with a low CAI by conventional scoring criteria or only mild desaturation, SS was related to poor therapy outcomes. The proposed algorithm for assessing SS as a measure of expressed high loop gain is accurate, non-invasive, and has the potential to improve phenotyping/endotyping of apnea, leading to more precise sleep apnea treatment strategies.

Non-rapid eye movement sleep slow-wave activity features are associated with amyloid accumulation in older adults with obstructive sleep apnoea.

Obstructive sleep apnoea (OSA) is associated with an increased risk for cognitive impairment and dementia, which likely involves Alzheimer's disease pathology. Non-rapid eye movement slow-wave activity (SWA) has been implicated in amyloid clearance, but it has not been studied in the context of longitudinal amyloid accumulation in OSA. This longitudinal retrospective study aims to investigate the relationship between polysomnographic and electrophysiological SWA features and amyloid accumulation. From the Mayo Clinic Study of Aging cohort, we identified 71 participants ≥60 years old with OSA (mean baseline age = 72.9 ± 7.5 years, 60.6% male, 93% cognitively unimpaired) who had at least 2 consecutive Amyloid Pittsburgh Compound B (PiB)-PET scans and a polysomnographic study within 5 years of the baseline scan and before the second scan. Annualized PiB-PET accumulation [global ΔPiB(log)/year] was estimated by the difference between the second and first log-transformed global PiB-PET uptake estimations divided by the interval between scans (years). Sixty-four participants were included in SWA analysis. SWA was characterized by the mean relative spectral power density (%) in slow oscillation (SO: 0.5-0.9 Hz) and delta (1-3.9 Hz) frequency bands and by their downslopes (SO-slope and delta-slope, respectively) during the diagnostic portion of polysomnography. We fit linear regression models to test for associations among global ΔPiB(log)/year, SWA features (mean SO% and delta% or mean SO-slope and delta-slope), and OSA severity markers, after adjusting for age at baseline PiB-PET, APOE ɛ4 and baseline amyloid positivity. For 1 SD increase in SO% and SO-slope, global ΔPiB(log)/year increased by 0.0033 (95% CI: 0.0001; 0.0064, P = 0.042) and 0.0069 (95% CI: 0.0009; 0.0129, P = 0.026), which were comparable to 32% and 59% of the effect size associated with baseline amyloid positivity, respectively. Delta-slope was associated with a reduction in global ΔPiB(log)/year by -0.0082 (95% CI: -0.0143; -0.0021, P = 0.009). Sleep apnoea severity was not associated with amyloid accumulation. Regional associations were stronger in the pre-frontal region. Both slow-wave slopes had more significant and widespread regional associations. Annualized PiB-PET accumulation was positively associated with SO and SO-slope, which may reflect altered sleep homeostasis due to increased homeostatic pressure in the setting of unmet sleep needs, increased synaptic strength, and/or hyper-excitability in OSA. Delta-slope was inversely associated with PiB-PET accumulation, suggesting it may represent residual physiological activity. Further investigation of SWA dynamics in the presence of sleep disorders before and after treatment is necessary for understanding the relationship between amyloid accumulation and SWA physiology.

Associations between self-reported parasomnias and psychiatric illness in 370,000 patients with sleep disorders.

To assess self-reported parasomnias in patients with sleep disorders and explore relationships with psychiatric illness, comorbidities, subjective sleep assessments, and polysomnographic study results. Results from intake questionnaires and polysomnographic assessments, collected from 240 sleep centers across 30 US states between 2004 and 2019, were analyzed retrospectively. Of 540,000 total patients, 371,889 who answered parasomnia-specific questions were included. Patients responding "often" or "always" to parasomnia-specific questions were considered "symptom-positive," whereas a "few times" or "never" were considered "symptom-negative" (controls). The study sample was 54.5% male with mean age 54 years (range, 2-107 years). Frequencies for the different parasomnias were 16.0% for any parasomnia, 8.8% for somniloquy, 6.0% for hypnagogic hallucinations, 4.8% for sleep-related eating disorder, 2.1% for sleep paralysis, and 1.7% for somnambulism. Frequent parasomnias were highly associated with diagnosed depression (odds ratio = 2.72). All parasomnias were associated with being younger and female and with symptoms of depression, anxiety, insomnia, restless legs, pain, medical conditions, fatigue, and sleepiness. Associations with objective sleep metrics showed characteristics of consolidated sleep and differentiated weakly between nonrapid eye movement sleep and rapid eye movement sleep parasomnias. Machine learning accurately classified patients with parasomnia versus controls (balanced accuracies between 71% and 79%). Benzodiazepines, antipsychotics, and opioids increased the odds of experiencing parasomnias, while antihistamines and melatonin reduced the odds. Z-drugs were found to increase the likelihood of a sleep-related eating disorder. Our findings suggest that parasomnias may be clinically relevant, yet understudied, symptoms of depression and anxiety. Further investigation is needed to quantify the nature of multimorbidity, including causality and implications for diagnosis and treatment.

Narcolepsy and Idiopathic Daytime Hypersomnia: A Study of Cohort in the Chilean Population

Introduction: Central disorders with hypersomnolence (CDH) are a group of sleep disorders characterized by excessive daytime sleepiness (EDS) that can be related to REM-sleep dissociative symptoms. They have a low prevalence in the population and may not be explained by other medical conditions. Materials and methods: A cohort of 59 Chilean patients with the most common types of CDH were studied. Clinical data, and results of polysomnography (PSG) plus multiple sleep latency tests (MSLT) were analyzed.. Results: The median age of the cohort was 35.26 ± 13.23 years (69.5% female). Diagnosis of narcolepsy Type 1, narcolepsy Type 2, and idiopathic daytime hypersomnia, were determined in 54.2%, 23.7% and 22% of patients respectively. All patients reported EDS, while 57.6%, 81.4% and 78% reported cataplexy, sleep paralysis and hypnagogic/hypnopompic hallucinations respectively. Polysomnographic studies showed non relevant alterations in the majority of patients. The MLTS was abnormal in all patients, 78% of them with 2 or more sleep onset REM periods (SOREMP). In 52.5% of cases, the delay in final diagnosis was more than 5 years. About a third of patients had another sleep disorder that could not explain the severity of EDS. We observed a comorbidity with an immunological disorder in 30.5% of patients. Conclusion: The EDS is the main symptom in CDH. Related REM-sleep symptoms and MSLT alterations were the second most important features to establish final diagnosis. However, we observed a significant delay in CDH diagnosis in the majority of patients.

Autonomic cardiovascular control is unaffected in children referred for assessment of excessive daytime sleepiness.

There is conflicting evidence for impaired autonomic control of heart rate (HR) in adults with narcolepsy and idiopathic hypersomnolence (IH). Despite these chronic hypersomnia conditions primarily being diagnosed around the age of puberty, there are limited studies in children. The present study investigated cardiovascular control using heart rate variability (HRV) and the extent of nocturnal HR dipping during sleep in children and adolescents with narcolepsy and IH. Children having an overnight polysomnographic study followed by a multiple sleep latency test (MSLT) for investigation of excessive daytime sleepiness (EDS) between May 2010 to December 2023 were included: 28 children diagnosed with narcolepsy, 11 with IH, and 26 subjectively sleepy children who did not meet the diagnostic criteria for either narcolepsy or IH. Each clinically referred child was matched for age and sex with a control. Time domain and frequency domain HRV were calculated from ECG recorded at 512 Hz. There were no differences in either time domain or spectral analysis of HRV between clinical groups or between clinical groups and their control group. The expected sleep state differences in HRV were observed in all groups. There was also no difference in HR nocturnal dipping between groups. Despite evidence for abnormal autonomic function in adults with narcolepsy and IH, our study did not identify any abnormalities in HR, HR control, or nocturnal dipping of HR in children referred for assessment of EDS. This suggests that autonomic dysfunction may be a feature of these conditions that develops in later life.

Duration of N1 sleep is a factor for excessive daytime sleepiness in epilepsy patients with interictal epileptiform discharges: A polysomnographic study

PurposeThis study aimed to identify the occurrence of excessive daytime sleepiness (EDS) in epilepsy patients with interictal epileptiform discharges and to explore the impact of interictal sleep architecture and sleep-related events on EDS. MethodsThis study included 101 epilepsy patients with interictal epileptiform discharges (IED) and 100 control patients who underwent simultaneous polysomnography and video ambulatory electroencephalography for >7 h throughout a single night. Multiple sleep latency tests were used to assess EDS. Comorbid EDS was present in 25 and 11 patients in the IED epilepsy and control groups, respectively. In addition, univariate and multivariate logistic regression analyses were performed to explore the factors influencing EDS. ResultsThe epilepsy group had a higher prevalence of comorbid EDS and shorter R sleep duration. Univariate logistic regression analysis indicated that an increased risk of EDS may be associated with prolonged N1 sleep duration, higher arousal index, lower mean saturation (mSaO2), higher oxygen desaturation index (ODI), and duration of wake after sleep onset (WASO). Multivariate logistic regression analysis revealed that N1 sleep duration was significantly correlated with EDS. ConclusionIn epilepsy patients with IED, the arousal index, mSaO2, ODI, and duration of WASO were weakly correlated with EDS, and the duration of N1 sleep demonstrated a significant positive correlation with EDS, which requires further research.

Safinamide effect on sleep architecture of motor fluctuating Parkinson's disease patients: A polysomnographic rasagiline-controlled study

IntroductionSleep problems commonly occur in Parkinson's disease (PD) and significantly affect patients' quality of life. A possible effect on subjective sleep disturbances of monoamine oxidase-B inhibitors (MAOB-Is) has been described. MethodsThis prospective, observational, single-centre study involved 45 fluctuating PD patients complaining sleep problems as documented by the PD Sleep Scale -2nd version (PDSS-2 ≥18) starting rasagiline 1 mg/daily or safinamide 100 mg/daily, according to common clinical practice, and maintaining antiparkinsonian therapy unchanged. Polysomnography (PSG), sleep questionnaires (PDSS-2, Epworth Sleepiness Scale - ESS), and motor function were evaluated at baseline (T0) and after 4 months of treatment (T1). ResultsSafinamide was prescribed in thirty patients and rasagiline in fifteen patients. Both drugs induced a significant improvement in Movement Disorder Society Unified PD Rating Scale III scores. Patients treated with rasagiline showed a significant increase in stage 1 (N1) Non-REM sleep compared to T0, with no significant effects on sleep scales. Patients treated with safinamide showed a significant increase in stage 3 of Non-REM sleep and sleep efficiency and a reduction in the rate of periodic limb movements, matching a significant reduction in PDSS-2 and ESS scales compared to T0. ConclusionThis study showed that safinamide, in addition to having a significant effect on PD motor symptoms, like the other MAOB-Is, may exert a specific beneficial effect on subjective and objective sleep, probably driven by its dual mechanism of action, which involves both dopaminergic and glutamatergic neurotransmission.

Cobalt ferrite-embedded polyvinylidene fluoride electrospun nanocomposites as flexible triboelectric sensors for healthcare and polysomnographic monitoring applications

Human respiration is a vital physiological function of the body and a key metric for assessing overall health, particularly in conditions related to sleep deprivation. However, developing a real-time system for detecting sleeping position, heartbeat, and respiration is challenging yet crucial. Such a system should be easy to fabricate, comfortable to wear, and highly sensitive. In this study, we fabricated a flexible electrospun cobalt ferrite (CoFe2O4, CF) embedded polyvinylidene fluoride (PVDF) nanocomposite (NC) using an electrospinning technique. Additionally, we investigated the influence of varying CF content (0, 1, 3, and 5 wt%) on the crystalline β-phase in PVDF. The triboelectric nanogenerator (TENG) device was fabricated using PVDF-CF (P-CF) NC as the tribo-negative layer and non-woven fabric of thermoplastic polyurethane (TPU) as the tribo-positive layer. Among the four sample combinations used in this study, P-CF-3 (3 wt% CF in PVDF)/TPU TENG exhibited a significantly higher triboelectric open circuit voltage (Voc) of 5.8 V, nearly three times higher as compared to P-CF-0/TPU TENG (1.7 V). This work demonstrates an efficient method for enhancing the output efficacy of flexible TENG devices by varying the nanofiller concentration. Moreover, the fabricated TENG device was efficiently tested for real-time healthcare monitoring (HCM) and polysomnographic (PSG) related studies. This study aspires to provide a novel and pragmatic way of identifying real-time sleeping disorders and respiratory monitoring.

The role of obstructive sleep apnea and nocturnal hypoxia as predictors of mortality in cancer patients

BackgroundObstructive sleep apnea (OSA), due to its high prevalence, has been associated with a number of comorbidities, frequently impacting the overall course of these other diseases if left untreated. Recent studies highlight a potential association between OSA and cancer. This study investigates how OSA severity and hypoxia affect cancer prognosis, aiming to elucidate how they interplay. MethodsRetrospective study including patients with a diagnosis of OSA after any cancer type followed up in a tertiary center during a 10-year period. OSA was mainly diagnosed after level III polysomnographic studies. ResultsNocturnal hypoxia was significantly more prevalent in patients presenting lung cancer versus other malignancies and was associated with higher rates of oncologic disease progression. Overall survival was significantly lower in severe OSA patients and also in patients presenting nocturnal hypoxia. A composite hypoxia score considering both OSA severity and significant hypoxia was an independent predictor of mortality regardless of clinical cancer staging and treatment. Shorter time between cancer and OSA diagnosis was also associated with worse prognosis. ConclusionThis study suggests an association between OSA severity and nocturnal hypoxia and increased cancer mortality independently from possible confounding factors such as age, cancer clinical staging at diagnosis, treatment modality and also progression. Neoplastic patients with severe OSA and/or complex hypoxia seem to have lower overall survival rates than those with less severe OSA and nocturnal hypoxia.

The yin and yang of two opponent processes of sleep-wake regulation: Sex-associated differences in the spectral EEG markers of the drives for sleep and wake

ABSTRACT Although objectively measured characteristics of sleep efficiency and quality were found to be better in women than men, women more frequently than men suffer from poor or insufficient or non-restorative sleep. We explored this apparent paradox by testing the sex-associated differences in electroencephalographic (EEG) indicators of two opponent processes of sleep-wake regulation, the drives for sleep and wake. We tried to provide empirical support for the hypothesis that a stronger women’s sleep drive can explain better objective characteristics of sleep quality in women than men, while a stronger women’s wake drive can be an explanation of a higher frequency of sleep-related complaints in women than men. To our knowledge, this was the first attempt to examine the associations of sex with scores on the 1st and 2nd principal components of the EEG spectrum that can serve as objective spectral EEG markers of the opponent drives for sleep and wake, respectively. The particular prediction was that, in women compared to men, not only the 1st principal component score but also the 2nd principal component score could be higher (i.e. both drives could be stronger). In a sample of 80 university students (40 females), the EEG signals were recorded during 160 afternoon napping attempts (50 min or longer). The difference between male and female students in sleep latencies did not reach a statistically significant level. In accordance with our prediction, both principal component scores were found to be higher in female than in male students irrespective of sleep stage. It is likely that the influence of the wake drive is entirely overlooked in the polysomnographic studies due to the predominant contribution of the indicators of the sleep drive to the conventional objective characteristics of sleep quality. Therefore, a stronger women’s sleep drive can be an explanation of women’s better sleep quality in the results of polysomnographic studies. On the other hand, if a stronger women’s wake drive can influence the perception of their sleep quality, this can explain their more frequent sleep-related complaints.

Excessive daytime sleepiness in myotonic dystrophy: a narrative review.

Excessive daytime sleepiness (EDS) is a common and debilitating symptom in both forms of myotonic dystrophy (DM), significantly impacting patients' quality of life. The review focuses on the purpose of examining the current understanding of EDS in these conditions, the difficulty in correctly accessing it, the recent findings related to its etiology and prevalence, and a summary of potential therapeutic implications. We conducted a comprehensive search through PubMed, selecting studies that provided significant insights into the mechanisms, prevalence, and management of EDS in DM1 and DM2. EDS is highly prevalent in both DM1 and DM2. Polysomnographic studies have revealed prominent dysregulation of REM sleep in DM1, suggesting a possible narcoleptic-like phenotype and alterations in NREM sleep that contributes to daytime sleepiness. Other factors have been proposed to explain EDS in DM1, including dysregulation of the sleep-wake circadian rhythm through nocturnal actigraphy analysis. The central origin of EDS is increasingly delineated supported by serotonin and orexin pathways dysfunction, and recent neuroradiological findings showing that in DM1 hippocampus volume was positively correlated with self-reported fatigue and somnolence. Sleep-disordered breathing and respiratory dysfunctions are prevalent in DM, their direct correlation with EDS remains complex and inconclusive, but respiratory evaluation should be recommended if obstructive sleep apneas or respiratory muscle dysfunctions are suspected. Drug interventions, such as modafinil and mexiletine, have shown promise in managing excessive daytime sleepiness and reducing myotonia without significant cardiac conduction effects. Enhancing EDS management in myotonic dystrophy is key to improving overall patient well-being.

OSApredictor: A tool for prediction of moderate to severe obstructive sleep apnea-hypopnea using readily available patient characteristics

Sleep apnea is a common sleep disorder. The availability of an easy-to-use sleep apnea predictor would provide a public health benefit by promoting early diagnosis and treatment. Our goal was to develop a prediction tool that used commonly available variables and was accessible to the public through a web site. Using data from polysomnography (PSG) studies that measured the apnea-hypopnea index (AHI), we built a machine learning tool to predict the presence of moderate to severe obstructive sleep apnea (OSA) (defined as AHI ≥15). Our tool employs only seven widely available predictor variables: age, sex, weight, height, pulse oxygen saturation, heart rate and respiratory rate. As a preliminary step, we used 16,958 PSG studies to examine eight machine learning algorithms via five-fold cross validation and determined that XGBoost exhibited superior predictive performance. We then refined the XGBoost predictor by randomly partitioning the data into a training and a test set (13,566 and 3392 PSGs, respectively) and repeatedly subsampling from the training set to construct 1000 training subsets. We evaluated each of the resulting 1000 XGBoost models on the single set-aside test set. The resulting classification tool correctly identified 72.5 % of those with moderate to severe OSA as having the condition (sensitivity) and 62.8 % of those without moderate to-severe OSA as not having it (specificity); overall accuracy was 66 %. We developed a user-friendly publicly available website (https://manticore.niehs.nih.gov/OSApredictor). We hope that our easy-to-use tool will serve as a screening vehicle that enables more patients to be clinically diagnosed and treated for OSA.