Sleep architecture as a candidate for phenotyping sleep bruxism: A narrative physiological review.

BACKGROUND: Sleep bruxism (SB), an oral behaviour in otherwise healthy individuals, is characterised by frequent rhythmic masticatory muscle activity (RMMA) during sleep. RMMA/SB episodes occur over various sleep stages (N1-N3 and rapid eye movement (REM)), sleep cycles (non-REM to REM), and frequently with microarousals. It currently remains unclear whether these characteristics of sleep architecture are phenotype candidates for the genesis of RMMA/SB. OBJECTIVES: This narrative review investigated the relationship between sleep architecture and the occurrence of RMMA as a SB phenotype candidate. METHODS: PubMed research was performed using keywords related to RMMA/SB and sleep architecture. RESULTS: In non-SB and SB healthy individuals, RMMA episodes were most frequent in the light non-REM sleep stages N1 and N2, particularly during the ascending phase of sleep cycles. The onset of RMMA/SB episodes in healthy individuals was preceded by a physiological arousal sequence of autonomic cardiovascular to cortical activation. It was not possible to extract a consistent sleep architecture pattern in the presence of sleep comorbidities. The lack of standardisation and variability between subject complexified the search for specific sleep architecture phenotype(s). CONCLUSION: In otherwise healthy individuals, the genesis of RMMA/SB episodes is largely affected by oscillations in the sleep stage and cycle as well as the occurrence of microarousal. Furthermore, a specific sleep architecture pattern cannot be confirmed in the presence of sleep comorbidity. Further studies are needed to delineate sleep architecture phenotype candidate(s) that contribute to the more accurate diagnosis of SB and treatment approaches using standardised and innovative methodologies.

Classification of bruxism based on time-frequency and nonlinear features of single channel EEG.

BACKGROUND: In the classification of bruxism patients based on electroencephalogram (EEG), feature extraction is essential. The method of using multi-channel EEG fusing electrocardiogram (ECG) and Electromyography (EMG) signal features has been proved to have good performance in bruxism classification, but the classification performance based on single channel EEG signal is still understudied. We investigate the efficacy of single EEG channel in bruxism classification. METHODS: We have extracted time-domain, frequency-domain, and nonlinear features from single EEG channel to classify bruxism. Five common bipolar EEG recordings from 2 bruxism patients and 4 healthy controls during REM sleep were analyzed. The time domain (mean, standard deviation, root mean squared value), frequency domain (absolute, relative and ratios power spectral density (PSD)), and non-linear features (sample entropy) of different EEG frequency bands were analyzed from five EEG channels of each participant. Fine tree algorithm was trained and tested for classifying sleep bruxism with healthy controls using five-fold cross-validation. RESULTS: Our results demonstrate that the C4P4 EEG channel was most effective for classification of sleep bruxism that yielded 95.59% sensitivity, 98.44% specificity, 97.84% accuracy, and 94.20% positive predictive value (PPV). CONCLUSIONS: Our results illustrate the feasibility of sleep bruxism classification using single EEG channel and provides an experimental foundation for the development of a future portable automatic sleep bruxism detection system.

Real-Time Deep Learning-Based Drowsiness Detection: Leveraging Computer-Vision and Eye-Blink Analyses for Enhanced Road Safety.

Drowsy driving can significantly affect driving performance and overall road safety. Statistically, the main causes are decreased alertness and attention of the drivers. The combination of deep learning and computer-vision algorithm applications has been proven to be one of the most effective approaches for the detection of drowsiness. Robust and accurate drowsiness detection systems can be developed by leveraging deep learning to learn complex coordinate patterns using visual data. Deep learning algorithms have emerged as powerful techniques for drowsiness detection because of their ability to learn automatically from given inputs and feature extractions from raw data. Eye-blinking-based drowsiness detection was applied in this study, which utilized the analysis of eye-blink patterns. In this study, we used custom data for model training and experimental results were obtained for different candidates. The blinking of the eye and mouth region coordinates were obtained by applying landmarks. The rate of eye-blinking and changes in the shape of the mouth were analyzed using computer-vision techniques by measuring eye landmarks with real-time fluctuation representations. An experimental analysis was performed in real time and the results proved the existence of a correlation between yawning and closed eyes, classified as drowsy. The overall performance of the drowsiness detection model was 95.8% accuracy for drowsy-eye detection, 97% for open-eye detection, 0.84% for yawning detection, 0.98% for right-sided falling, and 100% for left-sided falling. Furthermore, the proposed method allowed a real-time eye rate analysis, where the threshold served as a separator of the eye into two classes, the "Open" and "Closed" states.

[Study on the method of polysomnography sleep stage staging based on attention mechanism and bidirectional gate recurrent unit].

Polysomnography (PSG) monitoring is an important method for clinical diagnosis of diseases such as insomnia, apnea and so on. In order to solve the problem of time-consuming and energy-consuming sleep stage staging of sleep disorder patients using manual frame-by-frame visual judgment PSG, this study proposed a deep learning algorithm model combining convolutional neural networks (CNN) and bidirectional gate recurrent neural networks (Bi GRU). A dynamic sparse self-attention mechanism was designed to solve the problem that gated recurrent neural networks (GRU) is difficult to obtain accurate vector representation of long-distance information. This study collected 143 overnight PSG data of patients from Shanghai Mental Health Center with sleep disorders, which were combined with 153 overnight PSG data of patients from the open-source dataset, and selected 9 electrophysiological channel signals including 6 electroencephalogram (EEG) signal channels, 2 electrooculogram (EOG) signal channels and a single mandibular electromyogram (EMG) signal channel. These data were used for model training, testing and evaluation. After cross validation, the accuracy was (84.0±2.0)%, and Cohen's kappa value was 0.77±0.50. It showed better performance than the Cohen's kappa value of physician score of 0.75±0.11. The experimental results show that the algorithm model in this paper has a high staging effect in different populations and is widely applicable. It is of great significance to assist clinicians in rapid and large-scale PSG sleep automatic staging.

Suppressing the Morning Cortisol Rise After Memory Reactivation at 4 A.M. enhances Episodic Memory Reconsolidation in Humans.

Evidence from animal and human research shows that established memories can undergo changes after reactivation through a process called reconsolidation. Alterations of the level of the stress hormone cortisol may provide a way to manipulate reconsolidation in humans. Here, in a double-blind, within-subject design, we reactivated a 3-d-old memory at 3:55 A.M. in sixteen men and four women, immediately followed by oral administration of metyrapone versus placebo, to examine whether metyrapone-induced suppression of the morning cortisol rise may influence reconsolidation processes during and after early morning sleep. Crucially, reactivation followed by cortisol suppression versus placebo resulted in enhanced memory for the reactivated episode tested 4 d after reactivation. This enhancement after cortisol suppression was specific for the reactivated episode versus a non-reactivated episode. These findings suggest that when reactivation of memories is immediately followed by suppression of cortisol levels during early morning sleep in humans, reconsolidation processes change in a way that leads to the strengthening of episodic memory traces.SIGNIFICANCE STATEMENT How can we change formed memories? Modulation of established memories has been long debated in cognitive neuroscience and remains a crucial question to address for basic and clinical research. Stress-hormone cortisol and sleep are strong candidates for changing consolidated memories. In this double-blind, placebo-controlled, within-subject pharmacological study, we investigate the role of cortisol on the modulation of reconsolidation of episodic memories in humans. Blocking cortisol synthesis (3 g metyrapone) during early morning sleep boosts memory for a reactivated but not for a non-reactivated story. This finding contributes to our understanding of the modulatory role of cortisol and its circadian variability on reconsolidation, and moreover can critically inform clinical interventions for the case of memory dysfunctions, and trauma and stress-related disorders.

Sleep structure in sleep bruxism: A polysomnographic study including bruxism activity phenotypes across sleep stages.

The aim of the study was to assess sleep structure, phenotypes related to bruxism activity and basic respiratory parameters among a large group of participants with sleep bruxism and without obstructive sleep apnea. Adult participants with clinical suspicion of sleep bruxism and with no other significant medical history were recruited. Video-polysomnography was performed to detect masseter muscles activity. Polysomnographic scoring was performed according to the American Academy of Sleep Medicine Criteria. Finally, 146 participants were included. The participants were divided into three subgroups: severe, mild and no sleep bruxism. There were no differences in total sleep time, sleep latency, sleep efficiency, wake duration after sleep onset, rapid eye movement, and measured respiratory parameters. The severity of sleep bruxism contributed to the increased intensity of all sleep bruxism phenotypes in almost all sleep stages, apart from tonic and mixed activity in non-rapid eye movement stage 3 sleep (slow-wave sleep). Those with bruxism spent more time in rapid eye movement sleep compared to controls; there were no differences in non-rapid eye movement sleep stages. The results confirmed that sleep bruxism does not significantly affect sleep duration, efficiency and continuity (in terms of sleep-wake cycles). Sleep bruxism contributes to a higher percentage of rapid eye movement sleep in the total sleep time. Those with bruxism present more frequent episodes during all stages of sleep; however, in the case of slow-wave sleep, tonic and mixed activity observed in participants with sleep bruxism are comparable to those of healthy people.

Is there an association between sleep bruxism and obstructive sleep apnea syndrome? A systematic review.

PURPOSE: To elucidate current knowledge on the potential association and causality between sleep bruxism (SB) and obstructive sleep apnea (OSA) using full-night polysomnography. METHODS: Search strategies were developed for PubMed, Web of Science, Cochrane, LILACS, MEDLINE, and BBO-ODO and conducted until May 2019. The methodological quality was evaluated using the Qu-ATEBS tool. RESULTS: Two hundred seventy articles were identified and after independent screening of abstracts by two authors, 17 articles underwent full-text reading. Ten articles were excluded for not meeting the inclusion criteria and 7 were included in qualitative synthesis. Four studies support the association between SB and OSA: (a) a subtype of OSA patients may have SB as a protective response to respiratory events, (b) most episodes of bruxism occur shortly after the end of apnea/hypopnea (AH) events, (c) bruxism episodes occur secondary to arousals arising from AH events, and (d) there is a correlation between the frequency of SB and AH events, and three studies did not support: (e) AH episodes are related to non-specific SB oromotor activities, (f) SB episodes are not directly associated with the end of AH events, and (g) patients with OSA did not experience more SB events than control group. CONCLUSION: There is no scientific evidence to support a conclusive relationship between SB and OSA. Further, well-designed and randomized studies with control groups are needed to investigate whether possible mechanisms common to SB and OSA exist and whether OSA treatment could improve SB negative oral health outcomes in patients with SB and comorbidity of OSA.

A Portable Fuzzy Driver Drowsiness Estimation System.

The adequate automatic detection of driver fatigue is a very valuable approach for the prevention of traffic accidents. Devices that can determine drowsiness conditions accurately must inherently be portable, adaptable to different vehicles and drivers, and robust to conditions such as illumination changes or visual occlusion. With the advent of a new generation of computationally powerful embedded systems such as the Raspberry Pi, a new category of real-time and low-cost portable drowsiness detection systems could become standard tools. Usually, the proposed solutions using this platform are limited to the definition of thresholds for some defined drowsiness indicator or the application of computationally expensive classification models that limits their use in real-time. In this research, we propose the development of a new portable, low-cost, accurate, and robust drowsiness recognition device. The proposed device combines complementary drowsiness measures derived from a temporal window of eyes (PERCLOS, ECD) and mouth (AOT) states through a fuzzy inference system deployed in a Raspberry Pi with the capability of real-time response. The system provides three degrees of drowsiness (Low-Normal State, Medium-Drowsy State, and High-Severe Drowsiness State), and was assessed in terms of its computational performance and efficiency, resulting in a significant accuracy of 95.5% in state recognition that demonstrates the feasibility of the approach.

[Newer studies on the strong link between sleep and epilepsy: Epilepsy as an epileptic transformation of sleep plastic functions]. / Az alvás és az epilepszia szoros kapcsolatának újabb vizsgálatai: az epilepszia mint az alvási plaszticitásfunkció epilepsziás transzformációja.

Aims - Overview of the new data about the strong link of sleep and epilepsy and conjoining cognitive impairment. Methods - Search for relevant references and summary of our own research activity on the topic. Results - Strong interrealtionship exists between epilepsy and plastic brain functions (memory processing and synaptic homeostasis) and the working modes of NREM sleep. In the most frequent childhood and adult epilepsy networks responsible for plastic functions can be derailed to an epileptic level of excitability, and suffer a transitory or permanent epileptic transformation. Exampling on the three big epilepsies: absence epilepsy; medial temporal lobe epilepsy; and childhood idiopathic focal age dependent epilepsy spectrum we demonstrate the most important features of this epileptic transformation. The association of cognitive impairment to certain sleep dependent epilepsies gains explanation by the epilepsy caused interference with slow wave decline (ICFE) and memory consolidation (MTLE) during NREM sleep. This paper serves also to introduce the concept of sleep dependent system epilepsies. Conclusions - We provide evidences about shared mechanisms among sleep related epilepsies being the derailment of sleep plastic funcions toward exaggerated excitability determined by the inherent possibilities of the signal transduction properties.

Screen-printed ambulatory electrode set enables accurate diagnostics of sleep bruxism.

Currently, definite diagnosis of sleep bruxism requires polysomnography. However, it is restrictedly available, and too cumbersome and expensive for the purpose. The aim of this study was to introduce an ambulatory electrode set and evaluate its feasibility for more cost-effective diagnostics of sleep bruxism. Six self-assessed bruxers (one male, five females; aged 21-58 years) and six healthy controls (four males, two females, aged 21-25 years) underwent a standard polysomnographic study and a concurrent study with the ambulatory electrode set. Bruxism events, cortical arousals and sleep stages were scored for the two montages separately in a random order, and obtained sleep parameters were compared. In addition, the significance of video recording and sleep stage scoring for the diagnostic accuracy of ambulatory electrode set was determined. Ambulatory electrode set yielded similar diagnoses as standard polysomnography in all subjects. However, compared with standard polysomnography the median (interquartile range) tonic bruxism event index was significantly higher in the control group [+0.38 (+0.08 to +0.56) events per hour, P = 0.046], and the phasic bruxism event index was significantly lower in the bruxer group [-0.44 (-1.30 to +0.07) events per hour, P = 0.046]. Exclusion of video recording and both video recording and sleep stage scoring from analysis increased overestimation of the tonic bruxism event index in the control group +0.86 (+0.42 to +1.03) and +1.19 (+0.55 to +1.39) events per hour, P = 0.046 and P = 0.028, respectively], resulting in one misdiagnosed control subject. To conclude, ambulatory electrode set is a sensitive method for ambulatory diagnostics of sleep bruxism, and video recording and sleep stage scoring help reaching the highest specificity of sleep bruxism diagnostics.

Effectiveness of a mandibular advancement device in obstructive sleep apnea patients: a prospective clinical trial.

PURPOSE: This study aimed to determine the effectiveness of a mandibular advancement device in a sample of obstructive sleep apnea syndrome patients by the evaluation of respiratory and neurophysiologic parameters and clinical symptoms. Second, the influence of certain predictor factors related with the patient and the intraoral device, were considered in the final response with this treatment option. METHODS: Forty-one patients constituted the final sample. Outcomes were measured using polysomnography, Epworth sleepiness scale and an analogue visual snoring scale, before treatment and once the device was properly titrated. RESULTS: Mean apnea-hypopnea index decreased from 22.5 ± 16.8 to 9.1 ± 11.6 (p ≤ 0.05), influencing only gender and Fujita index as predictor factors. The oxygen saturation, arousal index, percentages of sleep stages and sleep efficiency significantly improved with the mandibular advancement device (MAD) placement. The snoring index improved in absolute terms in 6.1 units and the excessive daytime sleepiness was reduced from 12.2 ± 4.7 to 8.5 ± 3.8 (p ≤ 0.00). CONCLUSIONS: The successful treatment rate with the MAD was 65.8%. The placement and posterior regulation of the intraoral appliance efficiently reduced the apnea-hypopnea index, improved the sleep quality and the clinical symptomatology associated. Obstructive sleep apnea syndrome is a highly prevalent disease. and dentists should be aware of the benefits enhanced by this prosthetic device, considered the first treatment option by certain physicians.

An experimental study of adolescent sleep restriction during a simulated school week: changes in phase, sleep staging, performance and sleepiness.

This laboratory study investigated the impact of restricted sleep during a simulated school week on circadian phase, sleep stages and daytime functioning. Changes were examined across and within days and during a simulated weekend recovery. Participants were 12 healthy secondary school students (six male) aged 15-17 years [mean = 16.1 years, standard deviation (SD) = 0.9]. After 2 nights with 10 h (21:30-07:30 hours), time in bed was restricted to 5 h for 5 nights (02:30-07:30 hours), then returned to 10 h time in bed for 2 nights (21:30-07:30 hours). Saliva was collected in dim light on the first and last sleep restriction nights to measure melatonin onset phase. Sleep was recorded polysomnographically, and the Psychomotor Vigilance Task (PVT) and Karolinska Sleepiness Scale were undertaken 3-hourly while awake. Average phase delay measured by melatonin was 3 h (SD = 50 min). Compared to baseline, sleep during the restriction period contained a smaller percentage of Stages 1 and 2 and rapid eye movement (REM) and a greater percentage of Stage 4. PVT lapses increased significantly during sleep restriction and did not return to baseline levels during recovery. Subjective sleepiness showed a similar pattern during restriction, but returned to baseline levels during recovery. Results suggest that sustained attention in adolescents is affected negatively by sleep restriction, particularly in the early morning, and that a weekend of recovery sleep is insufficient to restore performance. The discrepancy between sleepiness ratings and performance may indicate a lack of perception of this residual impairment.

Insomnia complaints in lean patients with obstructive sleep apnea negatively affect positive airway pressure treatment adherence.

The objective of this study was to evaluate the determinants of long-term adherence to positive airway pressure treatment among patients with obstructive sleep apnea, with special emphasis on patients who stop positive airway pressure treatment within 1 year. This is a prospective long-term follow-up of subjects in the Icelandic Sleep Apnea Cohort who were diagnosed with obstructive sleep apnea between 2005 and 2009, and started on positive airway pressure treatment. In October 2014, positive airway pressure adherence was obtained by systematically evaluating available clinical files (n = 796; 644 males, 152 females) with moderate to severe obstructive sleep apnea (apnea-hypopnea index ≥15 events per h). The mean follow-up time was 6.7 ± 1.2 years. In total, 123 subjects (15.5%) returned their positive airway pressure device within the first year, 170 (21.4%) returned it later and 503 (63.2%) were still using positive airway pressure. The quitters within the first year had lower body mass index, milder obstructive sleep apnea, less sleepiness, and more often had symptoms of initial and late insomnia compared with long-term positive airway pressure users at baseline. Both initial and late insomnia were after adjustment still significantly associated with being an early quitter among subjects with body mass index <30 kg m-2 , but not among those with body mass index ≥30 kg m-2 . The prevalence of early quitters decreased significantly during the study period (2005-2009). Almost two-thirds of patients with moderate to severe obstructive sleep apnea are positive airway pressure users after 7 years. Obesity level, obstructive sleep apnea severity and daytime sleepiness are important determinants of long-term adherence. Symptoms of initial and late insomnia are associated with early quitting on positive airway pressure among non-obese subjects.

Oxycodone for cancer-related pain.

BACKGROUND: Many people with cancer experience moderate to severe pain that requires treatment with strong opioids, such as oxycodone and morphine. Strong opioids are, however, not effective for pain in all people, neither are they well-tolerated by all people. The aim of this review was to assess whether oxycodone is associated with better pain relief and tolerability than other analgesic options for adults with cancer pain. This is an updated version of the original Cochrane review published in 2015, Issue 2 on oxycodone for cancer-related pain. OBJECTIVES: To assess the effectiveness and tolerability of oxycodone by any route of administration for pain in adults with cancer. SEARCH METHODS: For this update, we searched the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library, MEDLINE and MEDLINE In-Process (Ovid), Embase (Ovid), Science Citation Index, Conference Proceedings Citation Index - Science (ISI Web of Science), BIOSIS (ISI), and PsycINFO (Ovid) to November 2016. We also searched four trial registries, checked the bibliographic references of relevant studies, and contacted the authors of the included studies. We applied no language, date, or publication status restrictions. SELECTION CRITERIA: We included randomised controlled trials (parallel group or cross-over) comparing oxycodone (any formulation or route of administration) with placebo or an active drug (including oxycodone) for cancer background pain in adults by examining pain intensity/relief, adverse events, quality of life, and participant preference. DATA COLLECTION AND ANALYSIS: Two review authors independently extracted data and assessed the included studies using standard Cochrane methodology. We meta-analysed pain intensity data using the generic inverse variance method, and adverse events using the Mantel-Haenszel method, or summarised these data narratively along with the quality of life and participant preference data. We assessed the overall quality of the evidence using GRADE. MAIN RESULTS: For this update, we identified six new studies (1258 participants) for inclusion. In total, we included 23 studies which enrolled/randomised 2648 participants, with 2144 of these analysed for efficacy and 2363 for safety. The studies examined a number of different drug comparisons.Pooled analysis of three of the four studies comparing controlled-release (CR) oxycodone to immediate-release (IR) oxycodone showed that the ability of CR and IR oxycodone to provide pain relief were similar (standardised mean difference (SMD) 0.1, 95% confidence interval (CI) -0.06 to 0.26; low quality evidence). Pooled analyses of adverse events showed no significant differences between CR and IR oxycodone for asthenia (risk ratio (RR) 0.58, 95% CI 0.2 to 1.68), confusion (RR 0.78, 95% CI 0.2 to 3.02), constipation (RR 0.71, 95% CI 0.45 to 1.13), dizziness/lightheadedness (RR 0.74, 95% CI 0.4 to 1.37), drowsiness/somnolence (RR 1.03, 95% CI 0.69 to 1.54), dry mouth (RR 1.14, 95% CI 0.48 to 2.75), insomnia (RR 1.04, 95% CI 0.31 to 3.53), nausea (RR 0.85, 95% CI 0.56 to 1.28), nervousness (RR 0.57, 95% CI 0.2 to 1.64), pruritus (RR 1.46, 95% CI 0.65 to 3.25), vomiting (RR 0.66, 95% CI 0.38 to 1.15), and discontinuation due to adverse events (RR 0.6, 95% CI 0.29 to 1.22). The quality of the evidence was very low for all these adverse events. Three of the four studies found similar results for treatment acceptability.Pooled analysis of seven of the nine studies comparing CR oxycodone to CR morphine indicated that pain relief was significantly better after treatment with CR morphine than CR oxycodone (SMD 0.14, 95% CI 0.01 to 0.27; low quality evidence). However, sensitivity analysis did not corroborate this result (SMD 0.12, 95% CI -0.02 to 0.26).Pooled analyses of adverse events showed no significant differences between CR oxycodone and CR morphine for confusion (RR 1.01 95% CI 0.78 to 1.31), constipation (RR 0.98, 95% CI 0.82 to 1.16), dizziness/lightheadedness (RR 0.76, 95% CI 0.33 to 1.76), drowsiness/somnolence (RR 0.9, 95% CI 0.75 to 1.08), dry mouth (RR 1.01, 95% CI 0.8 to 1.26), dysuria (RR 0.71, 95% CI 0.4 to 1.26), nausea (RR 1.02, 95% CI 0.82 to 1.26), pruritus (RR 0.81, 95% CI 0.51 to 1.29), vomiting (RR 0.94, 95% CI 0.68 to 1.29), and discontinuation due to adverse events (RR 1.06, 95% CI 0.43 to 2.6). However, the RR for hallucinations was significantly lower after treatment with CR oxycodone compared to CR morphine (RR 0.52, 95% CI 0.28 to 0.97). The quality of the evidence was very low for all these adverse events. There were no marked differences in treatment acceptability or quality of life ratings.The remaining studies either compared oxycodone in various formulations or compared oxycodone to different alternative opioids. None found any clear superiority or inferiority of oxycodone for cancer pain, neither as an analgesic agent nor in terms of adverse event rates and treatment acceptability.The quality of this evidence base was limited by the high or unclear risk of bias of the studies and by imprecision due to low or very low event rates or participant numbers for many outcomes. AUTHORS' CONCLUSIONS: The conclusions have not changed since the previous version of this review. The data suggest that oxycodone offers similar levels of pain relief and overall adverse events to other strong opioids including morphine. Although we identified a clinically insignificant benefit on pain relief in favour of CR morphine over CR oxycodone, this did not persist following sensitivity analysis and so we do not consider this important. However, in this updated analysis, we found that hallucinations occurred less often with CR oxycodone than with CR morphine, but the quality of this evidence was very low so this finding should be treated with utmost caution. Our conclusions are consistent with other reviews and suggest that while the reliability of the evidence base is low, given the absence of important differences within this analysis it seems unlikely that larger head to head studies of oxycodone versus morphine are justified, although well-designed trials comparing oxycodone to other strong analgesics may well be useful. For clinical purposes, oxycodone or morphine can be used as first-line oral opioids for relief of cancer pain in adults.

[Severe obstructive sleep apnea-hypopnea syndrome with dilated cardiomyopathy leading to pulmonary hypertension: case report and literature review].

Objective: To study the relationship between dilated cardiomyopathy and obstructive sleep apnea-hypopnea syndrome (OSAHS) and to evaluate the curative effects of continuous positive airway pressure (CPAP) in OSAHS complicated with dilated cardiomyopathy. Methods: We reported one case with the symptom of exertional dyspnea for 1 year and aggravating for 1 month. The patient finally was diagnosed with severe OSAHS complicated with dilated cardiomyopathy leading to pulmonary hypertension. A systematic literature review was performed for similar published cases in Pubmed, Wanfang and CNKI database, using the keywords (obstructive sleep apnea) OR(OSA) OR(OSAHS) AND(dilated cardiomyopathy OR DCM)from January 1990 to May 2016. Results: Our patient had no significant improvement after receiving initial treatments, including reducing cardiac preload, improving myocardial metabolism, increasing myocardial contractility, and anticoagulants. After the patient was diagnosed as having severe OSAHS by polysomnography(PSG) and treated with CPAP, his symptoms improved remarkably. The enlarged heart became smaller and the patient had no repeated dyspnea at follow-up examination. By literature review, we found 4 English original articles and 6 Chinese articles (1 review article, 1 expert note, 1 original article and 3 case reports) on OSAHS complicated by DCM.Four Chinese and 1 English articles reported that the symptoms and parameters of OSAHS with DCM was improved remarkably after treatment with CPAP. Conclusion: For patients with dilated cardiomyopathy which fails to conventional therapy, especially those accompanied by obesity, snoring, daytime sleepiness, morning dry mouth and other related symptoms, PSG should be carried out. Early CPAP therapy could improve symptoms and prognosis of OSAHS associated with DCM.

Assessment of the suitability of using a forehead EEG electrode set and chin EMG electrodes for sleep staging in polysomnography.

Recently, a number of portable devices designed for full polysomnography at home have appeared. However, current scalp electrodes used for electroencephalograms are not practical for patient self-application. The aim of this study was to evaluate the suitability of recently introduced forehead electroencephalogram electrode set and supplementary chin electromyogram electrodes for sleep staging. From 31 subjects (10 male, 21 female; age 31.3 ± 11.8 years), sleep was recorded simultaneously with a forehead electroencephalogram electrode set and with a standard polysomnography setup consisting of six recommended electroencephalogram channels, two electrooculogram channels and chin electromyogram. Thereafter, two experienced specialists scored each recording twice, based on either standard polysomnography or forehead recordings. Sleep variables recorded with the forehead electroencephalogram electrode set and separate chin electromyogram electrodes were highly consistent with those obtained with the standard polysomnography. There were no statistically significant differences in total sleep time, sleep efficiency or sleep latencies. However, compared with the standard polysomnography, there was a significant increase in the amount of stage N1 and N2, and a significant reduction in stage N3 and rapid eye movement sleep. Overall, epoch-by-epoch agreement between the methods was 79.5%. Inter-scorer agreement for the forehead electroencephalogram was only slightly lower than that for standard polysomnography (76.1% versus 83.2%). Forehead electroencephalogram electrode set as supplemented with chin electromyogram electrodes may serve as a reliable and simple solution for recording total sleep time, and may be adequate for measuring sleep architecture. Because this electrode concept is well suited for patient's self-application, it may offer a significant advancement in home polysomnography.

Depth-dependent changes of obstruction patterns under increasing sedation during drug-induced sedation endoscopy: results of a German monocentric clinical trial.

PURPOSE: Drug-induced sedation endoscopy (DISE) and simulated snoring (SimS) can locate the site of obstruction in patients with sleep-disordered breathing (SDB). There is clinical evidence for a change in collapsibility of the upper airway depending on the depth of sedation. So far, a dose-response relationship between sedation and collapsibility has not been demonstrated. METHODS: DISE and SimS were performed in 60 consecutive patients with SDB under monitoring of depth of sedation by BiSpectral Index® (BIS). Initially, SimS was conducted followed by DISE using bolus application of propofol. Sedation was performed up to a sedation level representing slow wave sleep (BIS = 40). The collapsibility of the upper airway was documented at decreasing sedation levels by an identical pictogram classification. RESULTS: For all levels and patterns of obstruction, a dose-dependent increase in the collapsibility of the upper airway was detected. A maximum collapsibility was achieved at sedation levels representing slow wave sleep. The collapsibility during SimS corresponded to light sleep stages and did not cover slow wave sleep. CONCLUSION: A dose-dependent change of patterns of obstructions can be observed during DISE under BIS monitoring indicating sedation depth. The obtained patterns of obstruction during DISE and SimS should thus be interpreted with regard to the sedation depth.

Objective and Subjective Outcomes Following Maxillomandibular Advancement Surgery for Treatment of Patients With Extremely Severe Obstructive Sleep Apnea (Apnea-Hypopnea Index >100).

PURPOSE: It is important for patients and treating clinicians to know whether maxillomandibular advancement (MMA) surgery is effective when treating patients with obstructive sleep apnea syndrome (OSAS) and an extremely high apnea-hypopnea index (AHI) score. The purpose of this study was to evaluate objective and subjective treatment outcomes after MMA surgery for the treatment of OSAS in patients with a preoperative AHI score higher than 100. PATIENTS AND METHODS: This retrospective study included all patients who underwent MMA surgery for OSAS by members of the Department of Oral and Maxillofacial Surgery, QEII Health Science Centre (Halifax, Nova Scotia, Canada) from November 1996 through February 2014. Objective data were available in the form of polysomnographs (PSGs) obtained before and a minimum of 6 months after surgery. Patients completed a self-administered questionnaire before and after surgery regarding snoring, witnessed apneas, continuous positive airway pressure (CPAP) use, daytime somnolence, and overall satisfaction. RESULTS: Two hundred sixty-five patients had MMA surgery, of which 13 had pre- and postoperative PSGs. PSGs showed a mean preoperative AHI score of 117.9 and a mean postsurgical AHI score of 16.1 (P < .001). Pre- and postoperative questionnaires were available for 9 patients. After surgery, 7 patients denied having any daytime sleepiness and 2 patients reported minimal daytime sleepiness. The mean preoperative Epworth Sleepiness Scale score was 12.9 (standard deviation [SD], 5.5), whereas the postoperative mean score was 5.0 (SD, 4.1; P = .004). Before surgery, all 9 patients reported loud snoring and 8 reported witnessed apneas. After surgery, 2 patients reported minimal snoring and only 1 patient continued to have witnessed apneas. Six patients used CPAP preoperatively and only 1 patient continued to use CPAP after surgery. CONCLUSIONS: The results of this study suggest that MMA surgery for treatment of extremely severe OSA can be a highly successful 1-stage surgery, which eliminates the use of CPAP, improves subjective outcomes, and considerably decreases the AHI score.

Spindle Oscillations in Sleep Disorders: A Systematic Review.

Measurement of sleep microarchitecture and neural oscillations is an increasingly popular technique for quantifying EEG sleep activity. Many studies have examined sleep spindle oscillations in sleep-disordered adults; however reviews of this literature are scarce. As such, our overarching aim was to critically review experimental studies examining sleep spindle activity between adults with and without different sleep disorders. Articles were obtained using a systematic methodology with a priori criteria. Thirty-seven studies meeting final inclusion criteria were reviewed, with studies grouped across three categories: insomnia, hypersomnias, and sleep-related movement disorders (including parasomnias). Studies of patients with insomnia and sleep-disordered breathing were more abundant relative to other diagnoses. All studies were cross-sectional. Studies were largely inconsistent regarding spindle activity differences between clinical and nonclinical groups, with some reporting greater or less activity, while many others reported no group differences. Stark inconsistencies in sample characteristics (e.g., age range and diagnostic criteria) and methods of analysis (e.g., spindle bandwidth selection, visual detection versus digital filtering, absolute versus relative spectral power, and NREM2 versus NREM3) suggest a need for greater use of event-based detection methods and increased research standardization. Hypotheses regarding the clinical and empirical implications of these findings, and suggestions for potential future studies, are also discussed.