Detection of Respiratory Events during Sleep Based on Fusion Analysis and Entropy Features of Cardiopulmonary Signals.

Sleep apnea hypopnea syndrome (SAHS) is a common sleep disorder with a high prevalence. The apnea hypopnea index (AHI) is an important indicator used to diagnose the severity of SAHS disorders. The calculation of the AHI is based on the accurate identification of various types of sleep respiratory events. In this paper, we proposed an automatic detection algorithm for respiratory events during sleep. In addition to the accurate recognition of normal breathing, hypopnea and apnea events using heart rate variability (HRV), entropy and other manual features, we also presented a fusion of ribcage and abdomen movement data combined with the long short-term memory (LSTM) framework to achieve the distinction between obstructive and central apnea events. While only using electrocardiogram (ECG) features, the accuracy, precision, sensitivity, and F1 score of the XGBoost model are 0.877, 0.877, 0.876, and 0.876, respectively, demonstrating that it performs better than other models. Moreover, the accuracy, sensitivity, and F1 score of the LSTM model for detecting obstructive and central apnea events were 0.866, 0.867, and 0.866, respectively. The research results of this paper can be used for the automatic recognition of sleep respiratory events as well as AHI calculation of polysomnography (PSG), which provide a theoretical basis and algorithm references for out-of-hospital sleep monitoring.

Mattress-Based Non-Influencing Sleep Apnea Monitoring System.

A mattress-type non-influencing sleep apnea monitoring system was designed to detect sleep apnea-hypopnea syndrome (SAHS). The pressure signals generated during sleep on the mattress were collected, and ballistocardiogram (BCG) and respiratory signals were extracted from the original signals. In the experiment, wavelet transform (WT) was used to reduce noise and decompose and reconstruct the signal to eliminate the influence of interference noise, which can directly and accurately separate the BCG signal and respiratory signal. In feature extraction, based on the five features commonly used in SAHS, an innovative respiratory waveform similarity feature was proposed in this work for the first time. In the SAHS detection, the binomial logistic regression was used to determine the sleep apnea symptoms in the signal segment. Simulation and experimental results showed that the device, algorithm, and system designed in this work were effective methods to detect, diagnose, and assist the diagnosis of SAHS.

A novel deep domain adaptation method for automated detection of sleep apnea/hypopnea events.

Objective.Sleep apnea-hypopnea syndrome (SAHS) is a common sleep-related respiratory disorder that is generally assessed for severity using polysomnography (PSG); however, the diversity of sampling devices and patients makes this not only costly but may also degrade the performance of the algorithms.Approach.This paper proposes a novel deep domain adaptation module which uses a long short-term memory-convolutional neural network embedded with the channel attention mechanism to achieve autonomous extraction of high-quality features. Meanwhile, a domain adaptation module was built to achieve domain-invariant feature extraction for reducing the differences in data distribution caused by different devices and other factors. In addition, during the training process, the algorithm used the last second label as the label of the PSG segment, so that second-by-second evaluation of respiratory events could be achieved.Main results.The algorithm applied the two datasets provided by PhysioNet as the source and target domains. The accuracy, sensitivity and specificity of the algorithm on the source domain were 86.46%, 86.11% and 93.17%, respectively, and on the target domain were 83.63%, 82.52%, 91.62%, respectively. The proposed algorithm showed strong generalization ability and the classification results were comparable to the current advanced methods. Besides, the apnea-hypopnea index values estimated by the proposed algorithm showed a high correlation with the manual scoring values on both domains.Significance.The proposed algorithm can effectively perform SAHS detection and evaluation with certain generalization.

Hellenic registry of patients with home mechanical ventilation (HR-HMV): profiling sleep Apnea-Hypopnea syndrome patients across Greece.

BACKGROUND: Chronic respiratory conditions are a prominent public health issue and thus, building a patient registry might facilitate both policy decision making and improvement of clinical management processes. Hellenic Registry of patients with Home Mechanical Ventilation (HR-HMV) was initiated in 2017 and a web-based platform is used to support patient data collection. Eighteen hospital departments (including sleep labs) across Greece participate in this initiative, focusing on recording data for both children and adult patients supported by mechanical ventilation at home, including patients with Sleep Apnea-Hypopnea Syndrome (SAHS) under Positive Airway Pressure (PAP) therapy. METHODS: The HR-HMV initiative ultimately aims to provide a database for evidence-based care and policy making in this specific domain. To this end, a web information system was developed and data were manually collected by clinics and hospital departments. Legal and privacy issues (such as General Data Protection Rule compliance and technical information security measures) have been considered while designing the web application. Based on the collected data, an exploratory statistical report of SAHS patients in Greece is presented. RESULTS: Eleven out of the eighteen participating clinics and hospital departments have contributed with data by the time of the current study. More than 5000 adult and children patient records have been collected so far, the vast majority of which (i.e., 4900 patients) diagnosed with SAHS. CONCLUSION: The development and maintenance of patient registries is a valuable tool for policy decision making, observational/epidemiological research and beyond (e.g., health technology assessment procedures). However, as all data collection and processing approaches, registries are also related with potential biases. Along these lines, strengths and limitations must be considered when interpreting the collected data, and continuous validation of the collected clinical data per se should be emphasized. Especially for Greece, where the lack of national registries is eminent, we argue that HR-HMV could be a useful tool for the development and the update of related policies regarding the healthcare services for patients with home mechanical ventilation support and SAHS patients, which could be useful for related initiatives at a European level as well.

Multi-Scale Evaluation of Sleep Quality Based on Motion Signal from Unobtrusive Device.

Sleep disorders are a growing threat nowadays as they are linked to neurological, cardiovascular and metabolic diseases. The gold standard methodology for sleep study is polysomnography (PSG), an intrusive and onerous technique that can disrupt normal routines. In this perspective, m-Health technologies offer an unobtrusive and rapid solution for home monitoring. We developed a multi-scale method based on motion signal extracted from an unobtrusive device to evaluate sleep behavior. Data used in this study were collected during two different acquisition campaigns by using a Pressure Bed Sensor (PBS). The first one was carried out with 22 subjects for sleep problems, and the second one comprises 11 healthy shift workers. All underwent full PSG and PBS recordings. The algorithm consists of extracting sleep quality and fragmentation indexes correlating to clinical metrics. In particular, the method classifies sleep windows of 1-s of the motion signal into: displacement (DI), quiet sleep (QS), disrupted sleep (DS) and absence from the bed (ABS). QS proved to be positively correlated (0.72±0.014) to Sleep Efficiency (SE) and DS/DI positively correlated (0.85±0.007) to the Apnea-Hypopnea Index (AHI). The work proved to be potentially helpful in the early investigation of sleep in the home environment. The minimized intrusiveness of the device together with a low complexity and good performance might provide valuable indications for the home monitoring of sleep disorders and for subjects' awareness.

The Recumbent Position Affects Nasal Resistance: A Systematic Review and Meta-Analysis.

OBJECTIVE: Nasal diseases are among the main motives for the early discontinuation of continuous positive airway pressure therapy and for long-term therapeutic compliance with mandibular advancement device. Although our clinical experience leads us to the belief that recumbency impacts nasal airflow in some patient populations, there is no consensus regarding the magnitude of this effect and the specific group of patients who are the most affected by this condition. In this study, we conducted a meta-analysis to assess the effect of the recumbent position on nasal resistance and nasal airflow. REVIEW METHODS: PubMed (Medline), Cochrane Library, EMBASE, Scopus, and SciELO databases were checked for relevant studies by two members of the YO-IFOS study group. The two authors extracted the data. The main outcome was expressed as the difference between nasal resistance and nasal airflow before and after recumbency. RESULTS: Nine studies with a total population of 291 individuals were included in the meta-analysis for nasal resistance after recumbency. We found a statistically significant difference in nasal airway resistance of -0.18 Pa sec/cm3 as compared to before and after recumbency through rhinomanometry (RMM) analysis. A subgroup analysis revealed a variation of -0.20 Pa sec/cm3 for patients with snoring or sleep apnea and - 0.10 Pa sec/cm3 for healthy individuals. Regarding nasal airflow measured with RMM, three studies (n = 32) in asymptomatic controls revealed a statistically significant difference of 47.33 ml/sec. CONCLUSIONS: Recumbency increases nasal resistance and diminishes nasal airflow. This finding is of utmost importance in snorers and sleep apnea patients. Laryngoscope, 132:6-16, 2022.

Faringoplastia de reposición modificada para el tratamiento del SAHS: cómo lo hacemos y nuestros resultados / Modified reposition pharyngoplasty for OSAS treatment: How we do it and our results

Introducción y objetivos: En los últimos 20años se ha descrito la relevancia de las paredes laterales faríngeas en el colapso de la vía aérea superior de pacientes con síndrome de apneas e hipopneas del sueño (SAHS). De ahí que hayan ido apareciendo nuevas técnicas quirúrgicas para mejorar este colapso. Nuestro objetivo es describir la técnica quirúrgica de la faringoplastia que realizamos y mostrar nuestros resultados iniciales.Material y métodosSe trata de un estudio retrospectivo en el que incluimos pacientes diagnosticados de SAHS que no toleran (o en los que no está indicado) el uso de CPAP. Los pacientes rellenaron un cuestionario previo a la cirugía en relación con sus hábitos de vida y con su roncopatía. Tras una exploración física completa tanto despierto como bajo somnoscopia, se procedió a esta intervención cuando observamos un colapso retropalatal y de paredes laterales faríngeas. En todos los pacientes se realizó un estudio de sueño preoperatorio así como entre los 3 y los 6meses tras la intervención, rellenando el mismo cuestionario en el postoperatorio a los 6meses. Calculamos la tasa de éxito según los criterios de Sher y, de una forma más restrictiva, según el criterio de índice de apnea-hipopnea (IAH) <10/h.ResultadosIncluimos un total de 26 pacientes, obteniendo un descenso significativo en el IAH de 29,1±18,3 a 12,3±12, sin cambios significativos en el IMC. Según criterios de Sher, en el 65,4% de los pacientes hubo un descenso del IAH a la mitad y <20/h, y el 42,3% del total consiguió un IAH <10/h. Obtuvimos resultados estadísticamente significativos en el resto de parámetros estudiados. La complicación más frecuente fue la extrusión parcial de la sutura.ConclusionesEsta cirugía obtiene resultados estadísticamente significativos tanto en los parámetros objetivos como subjetivos estudiados, sin complicaciones mayores asociadas. (AU)

Introduction and purposes: The relevance of the lateral pharyngeal walls in the collapse of the upper airway in obstructive sleep apnea patients has been revealed in the last 20years. New surgical techniques that address this collapse have been published. The aim of this study is to show the technique that we are currently using to treat the collapse and its results.Materials and methodsThis is a retrospective study of surgically treated OSAS patients who did not tolerate conventional positive airway pressure (CPAP) or for whom it was not indicated. After a complete physical examination either awake or under drug-induced sleep endoscopy, tonsillectomy with reposition pharyngoplasty was performed using barbed bidirectional suture and removing the supratonsillar fat. Three to 6months after surgery the subjective parameters were evaluated and a sleep study was performed.ResultsTwenty-six patients were enrolled with a significative decrease in the AHI and also significative improvement in all the rest parameters studied. In 65.4% of the patients the AHI decreased 50% and was lower than 20/h, in 42.3% postoperative AHI was lower than 10/h. The most frequent complication was the partial extrusion of the suture.ConclusionsThis surgical procedure obtains statistically significant results in objective and subjective parameters of sleep apnoea without major associated complications. (AU)

The Efficacy of Powered Oscillating Heads vs. Powered Sonic Action Heads Toothbrushes to Maintain Periodontal and Peri-Implant Health: A Narrative Review.

OBJECTIVES: To compare the efficacy of rotating-oscillating heads (ORHs) VS sonic action heads (SAHs) powered toothbrushes on plaque accumulation and gingival inflammation. METHODS: An electronic (MEDLINE, Embase, Inspec, PQ SciTech and BIOSIS) and a complementary manual search were made to detect eligible studies. RCTs meeting the following criteria were included: final timepoint longer than 15 days; year of publication after 2000; patients without orthodontic appliances or severe systemic/psychiatric diseases. Studies comparing two or more different types of sonic/roto-oscillating toothbrushes were excluded. Selection of articles, extraction of data, and assessment of quality were made independently by several reviewers. RESULTS: 12 trials (1433 participants) were included. The differences between ORHs and SAHs toothbrushes were expressed as weighted mean differences (WMD) and 95% confidence intervals (CI). The heterogeneity of data was evaluated. Concerning Plaque Index, both toothbrushes obtained comparable results. Six trials of up to 3 months and at an unclear risk of bias provided significant outcomes in terms of gingival inflammation in favor of ORHs toothbrush. Evidence resulting from three trials of up to 6 months and at a high/low risk of bias stated SAHs toothbrush superiority in gingival inflammation. CONCLUSIONS: Both ORHs and SAHs toothbrushes improved the outcomes measured from the baseline. In most of the good quality trials included, SAHs toothbrush showed statistical better long-term results. Due to the shortage of investigations, no further accurate conclusions can be outlined with reference to the superiority of a specific powered toothbrush over the other.

Modified reposition pharyngoplasty for OSAS treatment: How we do it and our results. / Faringoplastia de reposición modificada para el tratamiento del SAHS: cómo lo hacemos y nuestros resultados.

INTRODUCTION AND PURPOSES: The relevance of the lateral pharyngeal walls in the collapse of the upper airway in obstructive sleep apnea patients has been revealed in the last 20years. New surgical techniques that address this collapse have been published. The aim of this study is to show the technique that we are currently using to treat the collapse and its results. MATERIALS AND METHODS: This is a retrospective study of surgically treated OSAS patients who did not tolerate conventional positive airway pressure (CPAP) or for whom it was not indicated. After a complete physical examination either awake or under drug-induced sleep endoscopy, tonsillectomy with reposition pharyngoplasty was performed using barbed bidirectional suture and removing the supratonsillar fat. Three to 6months after surgery the subjective parameters were evaluated and a sleep study was performed. RESULTS: Twenty-six patients were enrolled with a significative decrease in the AHI and also significative improvement in all the rest parameters studied. In 65.4% of the patients the AHI decreased 50% and was lower than 20/h, in 42.3% postoperative AHI was lower than 10/h. The most frequent complication was the partial extrusion of the suture. CONCLUSIONS: This surgical procedure obtains statistically significant results in objective and subjective parameters of sleep apnoea without major associated complications.

Usefulness of recurrence plots from airflow recordings to aid in paediatric sleep apnoea diagnosis.

BACKGROUND AND OBJECTIVE: In-laboratory overnight polysomnography (PSG) is the gold standard method to diagnose the Sleep Apnoea-Hypopnoea Syndrome (SAHS). PSG is a complex, expensive, labour-intensive and time-consuming test. Consequently, simplified diagnostic methods are desirable. We propose the analysis of the airflow (AF) signal by means of recurrence plots (RP) features. The main goal of our study was to evaluate the utility of the information from RPs of the AF signals to detect paediatric SAHS at different levels of severity. In addition, we also evaluated the complementarity with the 3% oxygen desaturation index (ODI3). METHODS: 946 AF and blood oxygen saturation (SpO2) recordings from children ages 0-13 years were used. The population under study was randomly split into training (60%) and test (40%) sets. RP was computed and 9 RP features were extracted from each AF recording. ODI3 was also calculated from each SpO2 recording. A feature selection stage was conducted in the training group by means of the fast correlation-based filter (FCBF) methodology to obtain a relevant and non-redundant optimum feature subset. A multi-layer perceptron neural network with Bayesian approach (BY-MLP), trained with these optimum features, was used to estimate the apnoea-hypopnoea index (AHI). RESULTS: 8 of the RP features showed statistically significant differences (p-value <0.01) among the SAHS severity groups. FCBF selected the maximum length of the diagonal lines from RP, as well as the ODI3. Using these optimum features, the BY-MLP model achieved 83.2%, 78.5%, and 91.0% accuracy in the test group for the AHI thresholds 1, 5, and 10 events/h, respectively. Moreover, this model reached a negative likelihood ratio of 0.1 for 1 event/h and a positive likelihood ratio of 13.7 for 10 events/h. CONCLUSIONS: RP analysis enables extraction of useful SAHS-related information from overnight AF paediatric recordings. Moreover, it provides complementary information to the widely-used clinical variable ODI3. Thus, RP applied to AF signals can be used along with ODI3 to help in paediatric SAHS diagnosis, particularly to either confirm the absence of SAHS or the presence of severe SAHS.

The Four Horsemen (and their Nags): Recollections of the founding and early years of the American Academy of Neurology.

"The Four Horsemen" was the nickname given to the four neurologists-Abraham Baker, Francis Forster, Russell DeJong, and Adolph Sahs-who were most instrumental in founding and developing the American Academy of Neurology (AAN) beginning around 1948. Forster later humorously added "and their nags" to the epithet to reflect the cohesion of the founders and their wives. This article presents the personal recollections of these founders from correspondence and oral histories. When the AAN was founded, private-practice neurologists and residents were excluded from the academically oriented and restrictive American Neurological Association (ANA). Baker conceptualized the AAN as an inclusive professional society that would accept all neurologists of whatever age and level of training, and that would strive to strengthen their knowledge, competencies, and skills through continuing medical education and guideline development. Baker recruited supportive colleagues to help create and develop the organization. Their intention was not to compete with or subvert the ANA, but to offer an inclusive professional organization for all neurologists. Nevertheless, their efforts produced opposition among ANA members. To defuse the antagonism, neurologist Alphonse Vonderahe proposed an influential House-Senate formulation of the AAN-ANA relationship, modeled after the U.S. Congress, both as a supporting rationale for the AAN and as a conceptual model for the functional relationship between the two organizations. The inclusive approach greatly augmented the ranks of the fledgling AAN, whereas those of the ANA stayed relatively stagnant, with the AAN ultimately becoming the dominant neurological society. These neurologic pioneers laid the groundwork for an invigorated, well-trained, scientifically based specialty of neurology in the second half of the twentieth century.

Francis Forster, the last Horseman: A career in academic neurology.

American neurologist and epileptologist Francis M. Forster (1912-2006) was the last survivor of the "Four Horsemen," a nickname given to the four neurologists-Forster, Abe Baker, Russell DeJong, and Adolph Sahs-who were most instrumental in founding the American Academy of Neurology under Baker's leadership in 1948. Forster was a consulting physician for many high-profile patients, including President Dwight Eisenhower, President Quirino and Archbishop Reyes of the Philippines, Provisional President Lonardi of Argentina, and Cardinal Albert Meyer of Chicago. Forster was also an expert witness for the prosecution in the trial of Jack Ruby, who killed Lee Harvey Oswald. Forster's greatest legacy, though, was as a teacher: During his career as chairman of two robust academic neurology departments, he trained more than 100 residents, at least 17 of whom went on to become chairmen of neurology departments in the United States, Europe, Asia, and South America.

Joseph Resch and the plea of the practicing neurologists: A postwar neurology resident's tale.

When University of Minnesota neurology resident Joseph A. Resch complained to the department director, A. B. Baker, in 1946 about the lack of a professional neurological association open to young neurologists like himself, he set into motion a chain of events that culminated in the founding of the American Academy of Neurology in June of 1948. This provided a supportive professional organization for practicing neurologists as the traditional bond between neurology and psychiatry was broken during the postwar era. Resch went on to become a pivotal figure in the practice of neurology in the Twin Cities and succeeded Baker as chairman of the University of Minnesota neurology department.

Adolph Sahs: A neurologist who could take on still another job.

Adolph Louis Sahs (1906-1986) became chair of the Department of Neurology at the University of Iowa in 1948 and retired in 1974. Through his academic neurology organizational skills, coordination of multicenter research on subarachnoid hemorrhage, and education of more than 50 neurologists, he helped bring the department to national and international prominence. Sahs was one of the founders of the American Academy of Neurology. He served as president of the Academy, the American Neurological Association, and the American Board of Psychiatry and Neurology. Sahs was known as a neurologist who could always take on yet another job in the interest of the specialty.

Utility of bispectrum in the screening of pediatric sleep apnea-hypopnea syndrome using oximetry recordings.

BACKGROUND AND OBJECTIVE: The aim of this study was to assess the utility of bispectrum-based oximetry approaches as a complementary tool to traditional techniques in the screening of pediatric sleep apnea-hypopnea syndrome (SAHS). METHODS: 298 blood oxygen saturation (SpO2) signals from children ranging 0-13 years of age were recorded during overnight polysomnography (PSG). These recordings were divided into three severity groups according to the PSG-derived apnea hypopnea index (AHI): AHI < 5 events per hour (e/h), 5 ≤ AHI < 10 e/h, AHI ≥ 10 e/h. For each pediatric subject, anthropometric variables, 3% oxygen desaturation index (ODI3) and spectral features from power spectral density (PSD) and bispectrum were obtained. Then, the fast correlation-based filter (FCBF) was applied to select a subset of relevant features that may be complementary, excluding those that are redundant. The selected features fed a multiclass multi-layer perceptron (MLP) neural network to build a model to estimate the SAHS severity degrees. RESULTS: An optimum subset with features from all the proposed methodological approaches was obtained: variables from bispectrum, as well as PSD, ODI3, Age, and Sex. In the 3-class classification task, the MLP model trained with these features achieved an accuracy of 76.0% and a Cohen's kappa of 0.56 in an independent test set. Additionally, high accuracies were reached using the AHI cutoffs for diagnosis of moderate (AHI = 5 e/h) and severe (AHI = 10 e/h) SAHS: 81.3% and 85.3%, respectively. These results outperformed the diagnostic ability of a MLP model built without using bispectral features. CONCLUSIONS: Our results suggest that bispectrum provides additional information to anthropometric variables, ODI3 and PSD regarding characterization of changes in the SpO2 signal caused by respiratory events. Thus, oximetry bispectrum can be a useful tool to provide complementary information for screening of moderate-to-severe pediatric SAHS.

The relationship between apnoea hypopnoea index and Gensini score in patients with acute myocardial infarction undergoing emergency primary percutaneous coronary intervention.

BACKGROUND: Sleep apnoea hypopnoea syndrome (SAHS) is characterised by repetitive nocturnal hypoxemia and has a high prevalence among patients with acute myocardial infarction (AMI). But there are few studies on patients with AMI undergoing emergency primary percutaneous coronary intervention (pPCI). In this study, we want to find the prevalence of SAHS among patients with AMI undergoing emergency pPCI and determine whether SAHS would worsen the condition among these people, and especially affect the damage degree of the coronary artery. METHODS: Over four months, 95 patients admitted for the first time for AMI were observed. All of them had emergency primary PCIs. A total of 86 patients accepted the sleep study and were divided into four groups according to the apnoea hypopnoea index (AHI): SAHS was diagnosed when AHI ≥5/h and was defined as mild for AHI ≥5/h and <15/h, moderate for AHI ≥15/h and <30/h, and severe for AHI ≥30/h. On the contrary, the patients whose AHI <5/h were Non-SAHS. And the characteristics of the patients among these four groups were compared. According to the time of chest pain onset, the number of the patients between SAHS and non-SAHS, and patients' AHI during three intervals of one day were measured and compared; Makers including the sensitivity of serum troponin T (hs-TnT), creatine kinase isoenzyme MB (CK-MB), left ventricular ejection fraction (LVEF), pro-brain-type natriuretic peptide (pro-BNP), Gensini score and collateral vessels between the SAHS and non-SAHS were compared. And the relationships between the AHI of these patients and the markers were analysed. RESULTS: Of the 86 patients studied, 65 had SAHS, representing a SAHS prevalence of 75.58% among patients with AMI undergoing emergency pPCI. There were significant differences in average ages, smoking and arrhythmia (P<0.05) between these four groups. There was no significant difference between AMI patients with or without SAHS regarding the day-night pattern. But there showed significant differences between SAHS and non-SAHS in Gensini score (P<0.05) and pro-BNP (P<0.05). Also, there were positive correlations between AHI and Gensini score (r=0.490, P<0.05) and pro-BNP (r=0.338, P<0.05). CONCLUSIONS: Among patients with AMI undergoing emergency pPCI, there is a high prevalence of SAHS. There are also positive correlations between AHI and Gensini score, and pro-BNP. Therefore, guided by the results, should we conduct a routine screening to those patients normally and could we relieve the damage to the coronary artery by curing the SAHS?

A novel method to precisely detect apnea and hypopnea events by airflow and oximetry signals.

Sleep apnea hypopnea syndrome (SAHS) affects people's quality of life. The apnea hypopnea index (AHI) is the key indicator for diagnosing SAHS. The determination of the AHI is based on accurate detection of apnea and hypopnea events. This paper provides a novel method to detect apnea and hypopnea events based on the respiratory nasal airflow signal and the oximetry signal. The method uses sliding window and short time slice methods to eliminate systematic and sporadic noise of the airflow signal for improving the detection precision. Using this algorithm, the sleep data of 30 subjects from the Huaxi Sleep Center of Sichuan University (HSCSU) and the Teaching Hospital of Chengdu University of Traditional Chinese Medicine (THCUTCM) were auto-analyzed for detecting the apnea and hypopnea events. The total predicted apnea and hypopnea events were 8470. By manual investigation, the sensitivity and positive predictive value (PPV) of detecting apnea and hypopnea events were 97.6% and 95.7%, respectively. The sleep data of 28 subjects form HSCSU were auto-diagnosed SAHS according to the AHI. The sensitivity and PPV were 92.3% and 92.3%, respectively. This is an effective and precise method to diagnose SAHS. It can fit the home care SAHS screener.

Nurse-led intensive interventions improve adherence to continuous positive airway pressure therapy and quality of life in obstructive sleep apnea patients.

BACKGROUND: Continuous positive airway pressure (CPAP) is widely recommended for the treatment of sleep apnea/hypopnea syndrome (SAHS), but its usage by patients is very low. The aim of this study was to assess intensive educational programs and nursing support for the improvement of CPAP use and outcomes in SAHS patients. METHODS: Eighty new SAHS patients were randomized to receive nurse-led intensive interventions or usual support at hospital and home. The main outcome measure was CPAP use; changes in sleeping, symptoms, mood, and quality of life were also assessed after 12 months of treatment. RESULTS: All outcome measures were improved after treatment in both groups. However, patients receiving intensive support with significantly higher CPAP use (higher daily CPAP usage by 2.2 hours/day) had greater improvements in SAHS symptoms and mood (P<0.05). The intervention group further showed an improvement in the Short Form-36 domains of mental and physical health (P<0.05). CONCLUSION: The CPAP usage and quality of life can be significantly improved by nurse-led intensive program in obstructive sleep apnea patients.

Relationship Between Sleep Apnea and Cancer.

In the light of relationships reported between hypoxemia (tissue hypoxia) and cancer, Abrams et al. concluded in 2008 that sleep apnea-hypopnea syndrome (SAHS) and its main consequence, intermittent hypoxia, could be related with increased susceptibility to cancer or poorer prognosis of a pre-existing tumor. This pathophysiological association was confirmed in animal studies. Two large independent historical cohort studies subsequently found that the degree of nocturnal hypoxia in patients with SAHS was associated with higher cancer incidence and mortality. This finding has been confirmed in almost all subsequent studies, although the retrospective nature of some requires that they be considered as hypothesis-generating only. The relationship between sleep apnea and cancer, and the pathophysiological mechanisms governing it, could be clarified in the near future in a currently on-going study in a large group of melanoma patients.

Análisis multicanal de un sensor no obstructivo para la detección del Síndrome de Apnea-Hipopnea del Sueño / Multichannel Analysis of an Unobtrusive Sensor for Sleep Apnea-Hypopnea Detection

Este artículo presenta un método no obstructivo para la detección del síndrome de apnea-hipopnea del sueño (SAHS). El flujo respiratorio es medido indirectamente a través de un colchón sensorizado (PBS Pressure Bed Sensor) que incluye 8 transductores de presión. Mediante la transformada de Hilbert se obtiene la amplitud instantánea de las señales respiratorias y se reduce la información a través del análisis de componentes principales (ACP). Los eventos respiratorios (ERs apneas/hipopneas) se localizan como una reducción en la amplitud instantánea resultante y se contabilizan en el índice de eventos respiratorios (IER), un índice de severidad similar al oficial apnea-hypopnea index (AHI). El PBS se analiza agrupando primero la información de pares de canales y después utilizando los 8 canales. Los IER se evalúan comparándolos con el AHI en diferentes niveles de severidad. En el diagnóstico de pacientes sanos y patológicos se obtuvo una sensibilidad, especificidad y exactitud de 92%, 100% y 96% respectivamente, utilizando la información de dos u ocho canales. Con estos resultados podemos proponer el uso del PBS como una alternativa para el diagnóstico del SAHS en ambientes fuera del hospital, ya que no requiere la presencia de un clínico especialista para su uso.

This manuscript presents an unobtrusive method for sleep apneahypopnea syndrome (SAHS) detection. The airflow is indirectly measured through a sensitive mattress (Pressure Bed sensor, PBS) that incorporates multiple pressure sensors into a bed mattress. The instantaneous amplitude of each sensor signal is calculated through Hilbert transform, and then, the information is reduced via principal component analysis. The respiratory events (ERs -apneas/hypopneas) are detected as a reduction in the resulting instantaneous amplitude and accounted in the respiratory event index (IER), which is a severity indicator similar to the offcial apnea-hypopnea index (AHI). The respiratory signals extracted from PBS are analyzed first by clustering the information coming from channel pairs, and then using the eight channels. The IER performance is compared with the AHI for different severity categories. For the diagnosis of healthy and pathological patients we obtain a sensitivity, specificity and accuracy of 92%, 100% and 96%, respectively using two or eight PBS channels. These results suggest the possibility to propose PBS as an alternative tool for SAHS diagnosis in home environment.