Obstructive Sleep Apnea Episodes Research Articles

Blood Pressure Regulation and Hypertension in Obstructive Sleep Apnea Syndrome: A Historical Perspective.

In obstructive sleep apnea syndrome (OSAS), an underlying disease of secondary hypertension, repeated episodes of asphyxia due to obstructive sleep apnea (OSA), followed by arousal, lead to various cardiovascular consequences. Using a canine model of OSAS, it was found that a single load of OSA caused an abrupt increase in blood pressure (BP) (Apnea Surge in seconds), while multiple OSA episodes occurring nightly for 1-3 months led to a sustained elevation of BP during both nighttime and daytime. Epidemiological studies on 24-hour ambulatory BP measurements revealed that some hypertensive patients experienced elevated BP in the early morning (Morning Surge), which could be intensified by OSAS. The resonance of Apnea Surge in seconds and Morning Surge increases the risk of organ damage, triggers the cardiovascular events, and adversely affects the prognosis of hypertensive patients with OSAS.For ameliorating these risks, OSA should be treated with positive airway pressure properly.

Obstructive sleep apnea syndrome in patients with chronic rheumatic heart disease

Introduction. The presence of obstructive sleep apnea (OSAS) in patients with chronic heart failure (CHF) increases cardiovascular and overall mortality in comparison with patients without breathing disorders during sleep.Aim of study. Assessment of prevalence and dynamics of OSAS in patients with CHF due to rheumatic heart disease (RHD).Materials and methods. The study included 172 patients with RHD. OSAS was assessed using a cardiorespiratory monitor “Kardiotekhnika-04-3Р (M)”.Results and discussion. Analysis of echocardiography results of showed a significant increase in the linear dimensions of the LV: for LVED B = 0.020 (0.013; 0.027), p = 0.001, R2 = 0.087; for LVES B = 0.017 (0.010; 0.024), p = 0.001, R2 = 0.073. An increase in the indices of hypertrophy was also revealed – LVPW and IVS: for IVS B = 0.008 (0.006; 0.010), p = 0.001, R2 = 0.148; for LVPW B = 0.006 (0.004; 0.08), p = 0.001, R2 = 0.087. The highest values of echocardiography indicators were achieved in the group with OSAS III, in comparison with patients without OSAS. significantly differed: for LVED – 0.86 cm, for LVES – 0.56 cm, for IVS – 0.41 cm, for LVPW – 0.34 cm. but there was also the maximum distance of the 6-minute walk test – 390.02 (360.15; 419.88) meters. Assessment of the quality of life according to the summary scales of the questionnaires showed a higher level of quality of life in the group without OSAS according to the physical health SF-36 (B = -0.100 (-0.169; -0.031), p = 0.005, R2 = 0.029), mental health SF-36 B = 0.120 (-0.091; 0.115), p = 0.821) and according to overall summary score KCCQ (B = -0.289 (-0.473; -0.105), p = 0.002, R2 = 0.036).Conclusion. In the dynamics over 10 years, in patients with RHD, there was an increase in the number of episodes of obstructive and central apnea, an increase in the frequency of episodes of apnea / hypopnea with desaturation and snoring. However, a significant increase was achieved only in the case of obstructive sleep apnea episodes – by 14.60 episodes.

Successful continuous positive airway pressure treatment reduces skin sympathetic nerve activity in patients with obstructive sleep apnea.

Obstructive sleep apnea (OSA) is associated with cardiovascular diseases and increased sympathetic tone. We previously demonstrated that patients with OSA have increased skin sympathetic nerve activity (SKNA). The purpose of this study was to test the hypothesis that continuous positive airway pressure (CPAP) treatment reduces SKNA. The electrocardiogram, SKNA, and polysomnographic recording were recorded simultaneously in 9 patients with OSA. After baseline recording, CPAP titration was performed and the pressure was adjusted gradually for the optimal treatment, defined by reducing the apnea-hypopnea index (AHI) to ≤5/h. Otherwise the treatment was considered suboptimal (AHI > 5/h). Fast Fourier transform analyses were performed to investigate the frequency spectrum of SKNA. There were very low frequency (VLF), low frequency (LF), and high frequency (HF) oscillations in SKNA. The HF oscillation matched the frequency of respiration. OSA episodes were more frequently associated with the VLF and LF than with the HF oscillations of SKNA. Compared with baseline, CPAP significantly decreased the arousal index and AHI and increased the minimal and mean oxyhemoglobin levels. Optimal treatment significantly increased the dominant frequency and reduced the heart rate, average SKNA (aSKNA), SKNA burst duration, and total burst area. The dominant frequency negatively correlated with aSKNA. VLF, LF, and HF oscillations are observed in human SKNA recordings. Among them, VLF and LF oscillations are associated with OSA while HF oscillations are associated with normal breathing. CPAP therapy reduces aSKNA and shifts the frequency of SKNA oscillation from VLF or LF to HF.

460 Assessment of long-term arrhytmic sequelae in patients recovering from COVID-19 infection

AimsCOVID-19 has been associated with acute cardiac complications including cardiac arrhythmias. We aimed to assess the prevalence of long-term cardiac arrhythmias in patients recovering from severe COVID-19 infection with proved or suspected of cardiac involvement.Methods and resultsAll patients with COVID-19 infection discharged from the cardiology department of our institution from the 1 March to the 30 April 2020 were considered eligible for this study. Patients were fitted out with an adhesive patch and a wireless single-lead 24-h electrocardiogram (ECG) Holter monitor (Rooti Rx® System, Rooti Labs Ltd, Taipei, Taiwan). RootiRx® is a small device consisting of an integrated sensor system, a microelectronic board with memory storage, and an internal rechargeable battery. This system can provide continuous ECG and was set to monitor heart rhythm for 24 h. The Holter system provides also blood pressure measurements and sleep apnea data which are evaluated through chest wall motion/cyclic variation of heart rate and reported along with the sleep efficiency (percentage of time spent asleep while in bed). Arrhythmic findings, sleep apnea detections, and residual COVID-19 symptoms were reported. The study follow-up was performed 174 (range = 166–190) days after hospital discharge in a cohort of 63 (76% males, median age 66 years) patients. New diagnosis of atrial fibrillation (AF) was performed in three sinus rhythm patients (4.8%). Eleven (18%) patients had asymptomatic bradycardia (<45 b.p.m.) with no pauses lasting more than 3 s. Non-sustained ventricular tachycardia (<30 s) episodes were recorded in two (3.2%) patients, while no sustained ventricular arrhythmia was documented. The Holter system indicated the presence of moderate-to-severe obstructive sleep apnea episodes in 33 (53%) patients without known history of sleep disorders. Some previously unrecognized long-lasting COVID-19 symptoms were also described: fatigue (10, 16%), myalgia (3, 4.8%), and impaired attention (1, 1.6%).ConclusionsSix months after the infection, we performed new diagnoses of AF in patients who recovered from severe COVID-19 infection with proved or suspected cardiac involvement using 24-h Holter monitoring. No other arrhythmias were observed, but the Holter system identified obstructive sleep apnea episodes in half of the patients. A relevant percentage of patients also described persisting symptoms of COVID-19 infection. These findings suggest further prospective studies to better describe long-term arrhythmic manifestations and residual symptoms in patients hospitalized with COVID-19 infection.

Swallowing disorders in patients with obstructive sleep apnea: a critical literature review.

Patients with obstructive sleep apnea (OSA) may show signs and symptoms of altered swallowing function since repetitive episodes of OSA may cause hypoxia (decreased oxygen concentration in the blood) and hypercapnia (increased carbon dioxide concentration in the blood), as well as neuromuscular changes in the tissues involved, including the pharynx. This study aims to analyze whether patients with OSA show signs and symptoms of altered swallowing function. A literature search was performed in the PubMed, LILACS, Medline, Scopus, and SciELO databases by using the following search strategy: (“dysphagia”) or (“deglutition disorders”) and (“obstructive sleep apnea”) or (“obstructive sleep apnea syndrome”). The included articles were sorted by authors, year, country, journal of publication, and type of study, as well as analyzed according to the objectives, case series, OSA and swallowing assessment methods, results and conclusions. After applying the inclusion and exclusion criteria, ten articles published in medicine, dentistry and physiology journals between 1999 and 2018 were selected. The analysis of the selected articles showed that the number of participants and group structuring vary according to the study and instrumental and objective exams are used to assess swallowing and sleep in most articles. Also, the results show that groups of patients with OSA can present altered swallowing reflex, altered latency time and inspiratory suppression time, and presence of premature posterior escape, residues, penetration and aspiration. Premature posterior escape was the most frequent sign found. In conclusion, patients with OSA may show signs and symptoms of altered swallowing function.

Shared pathways, targets and biomarkers of sleep apnea and gout

In the period from 2011 to 2020, 4 large-scale population-based studies were conducted to identify gout in patients with obstructive sleep apnea (OSA), as well as one study to detect the frequency of sleep apnea in patients with gout.All recently published studies confirm connection between the development of OSA and an increase in the level of uric acid in blood serum, both against the background of clinically significant gout arthritis and without it. However, only one big population-based study during 2010 — 2020 assessed the development of OSA against the background of gout. According to this study, incidence of OSA was 14.3 per 1.000 person-years in patients with gout, compared with 3.9 per 1.000 person-years without gout, with HR = 2.07 (95 % CI 2.00 — 2.15 %), which is significantly higher than the incidence of gout in patients with OSA, even taking into account hypertension and hyperlipidemia.The data from these studies showed an undoubted relationship between the two diseases, but to date it is not completely known how much it is due to common risk factors and how interlinked the development mechanisms are. Older age and restricted mobility put patients with gout at a significant risk during OSA episodes. In cases where the treatment of both diseases is conducted independently, the volume of drug therapy and the likelihood of developing negative side effects increase. In this regard, it is necessary to monitor patients with gout who develop sleep apnea differently to gout only patients, as well as to prescribe adequate treatment for both diseases.In our review, we aimed to show the most recent information on the mechanisms of gout-OSA development, shared pathways, targets and biomarkers, emphasizing the likely ways that cause the progression of OSA in patients with gout. In addition, analysis of the latest publications to date showed nonuniformity in study subjects, allowing to identify different subtypes of gout-OSA patients: combined with metabolic syndrome (most common), combined with renal dysfunction without obesity, and others (dietary violations, genetic diseases, acidosis).

Abstract 14965: Atrial Conduction During Obstructive Sleep Apnea: Comparison of Stacked Versus Isolated Apnea Episodes

Introduction: Obstructive sleep apnea (OSA) is associated with increased rates of atrial fibrillation (AF). Recent randomized data suggest that traditional scoring of OSA needs to evolve to improve cardiovascular outcomes. Traditional scoring of OSA does not fully reflect pathophysiological links between OSA and AF, particularly regarding OSA-induced prolongation of p-wave duration (PWD), which is the most powerful predictor of AF occurrence. Hypothesis: We hypothesized that OSA episodes that closely follow each other (serially stacked apneas, ssOSA) exert greater effect on PWD compared to isolated OSA (iOSA) episodes. Methods: Sleeping patients (adults with mild-moderate OSA and presence of both iOSA and ssOSA, but without other cardiovascular comorbidities) undergoing diagnostic polysomnography were recorded by continuous 8-lead ECG. iOSA was defined as OSA episodes with no other episode within 30 seconds. ssOSA consisted of ≥3 consecutive apneas with inter-OSA intervals &lt;30 seconds. PWD was defined from onset of p-wave in any ECG lead to termination in any lead (measured by digital calipers, averaged over 3 beats from first half of OSA and 3 beats from second half of OSA). Wilcoxon rank-sum test was used. Results: We analyzed 208 OSA episodes (51.0% iOSA, 49.0% ssOSA) which occurred in 12 patients (7 women; age 63.1±11.5 years; apnea hypopnea index 16.8±5.4). PWD was longer during ssOSA compared to iOSA (median 117.7ms vs 109.6ms; p&lt;0.0001). The following variables did not differ between ssOSA and iOSA: PR interval (p=0.3139), RR interval (p=0.7531), peripheral oxygen saturation (p=0.7776). Conclusions: The impact of OSA on atrial conduction delay is exacerbated by the phenomenon of OSA stacking, which seems independent of oxygen desaturation and heart rate. Stacking of OSA episodes may be an underused and cost-efficient variable in evaluating the severity of OSA and the effectiveness of OSA treatments with the ultimate goal of reducing occurrence of AF.

Apache Spark SVM for Predicting Obstructive Sleep Apnea

Obstructive sleep apnea (OSA), a common form of sleep apnea generally caused by a collapse of the upper respiratory airway, is associated with one of the leading causes of death in adults: hypertension, cardiovascular and cerebrovascular disease. In this paper, an algorithm for predicting obstructive sleep apnea episodes based on a spark-based support vector machine (SVM) is proposed. Wavelet decomposition and wavelet reshaping were used to denoise sleep apnea data, and cubic B-type interpolation wavelet transform was used to locate the QRS complex in OSA data. Twelve features were extracted, and SVM was used to predict OSA onset. Different configurations of SVM were compared with the regular, as well as Spark Big Data, frameworks. The results showed that Spark-based kernel SVM performs best, with an accuracy of 90.52% and specificity of 93.4%. Overall, Spark-SVM performed better than regular SVM, and polynomial SVM performed better than linear SVM, both for regular SVM and Spark-SVM.

Increased heart rate with sleep disordered breathing in hypertrophic cardiomyopathy

BackgroundCurrent guidelines recommend medications with rate control properties for symptomatic patients with hypertrophic cardiomyopathy (HCM) based on the rationale that lowering heart rate (HR) improves their symptoms. Whether sleep disordered breathing (SDB) is associated with increased HR in HCM patients is not known. MethodWe diagnosed uncontrolled SDB (oxygen desaturation index ≥5) in consecutive echocardiographically confirmed HCM patients seen at Mayo Clinic, Rochester, and analyzed their HR as recorded by a 24-h Holter monitor. We compared mean, minimum, maximum HR between those with vs without SDB. In a pilot subanalysis of HCM patients with SDB who also underwent subsequent diagnostic polysomnography (PSG), we analyzed RR interval changes coinciding with obstructive sleep apnea and hypopnea episodes. ResultsOf the 230 HCM patients included in this study (age 54 ± 16 years; 138 male; LVOT pressure gradient at rest 45 ± 39 mmHg), 115 (50%) patients had SDB. HCM patients with SDB were recorded to have higher mean HR (71 vs. 67 bpm; p = .002, adjusted p = .001), and this difference was most pronounced during night hours of 10 PM to 5 AM (61 vs. 67 bpm; p < .001). In the pilot analysis of the available PSG data, the release of obstructive sleep apneas and hypopneas coincided with fluctuation of HR. ConclusionsSDB is independently associated with higher mean HR in patients with HCM, and this difference is most significant during sleep. Treatment of SDB, which is readily available, should be tested as a complementary modality to the currently recommended pharmacotherapy aimed at lowering HR in patients with symptomatic HCM.

1065 A Bout of Sleep Apnea or a Posttrauma Nightmare Occurrence?

Abstract Introduction The enigmatic nature of Posttrauma Nightmares (PTNs) has left research without an agreed upon operational definition. This is partially due to PTNs often containing well remembered content that is similar to the triggering trauma, but also manifesting as severe nighttime awakenings without a concise or remembered dream narrative. Given that recent research has linked episodes of Obstructive Sleep Apnea (OSA) to PTNs, this study aimed to examine if OSA could explain why some distressed awakenings occur without memory of nightmare content. Methods Participants included 36 trauma survivors who reported experiencing PTNs, recruited from a clinical referral or at a Veterans Affairs Hospital. Presence of OSA was captured from self-reports of previous polysomnography-based sleep study results. PTNs were measured via a self-report measure that assessed past month nightmare frequency and if the content was remembered upon awakening. Analysis included descriptive statistics and chi-square tests. Results Out of the group with a reported diagnosis of OSA (N = 8), 75% (n = 6) reported they did not remember the content of their nightmares upon awakening, whereas out of the group without a reported OSA diagnosis (N = 28), only 4% of participants (n = 1) reported not remembering the content of their nightmares. There was a significant difference between OSA diagnosis and remembering nightmare content (X2 = 57.83, p &amp;lt; 0.001). Conclusion Individuals with diagnosed OSA commonly experienced nightmares that were often not remembered upon awakening, while the group without OSA most often remembered the content of their nightmares. Due to this relationship, it is possible that some PTNs experienced by the OSA group may instead be misinterpreted respiratory events. Understanding the relationship between OSA and PTNs is crucial for developing the most effective treatment course. Support None.

0439 Nonlinear Dynamics Forecasting for Personalize Prognosis of Obstructive Sleep Apnea Onsets

Abstract Introduction The emphasis on disease prevention, early detection, and preventive treatments will revolutionize the way sleep clinicians evaluate their patients. Obstructive Sleep Apnea (OSA) is one of the most prevalent sleep disorders with approximately 100 millions patients been diagnosed worldwide. The effectiveness of sleep disorder therapies can be enhanced by providing personalized and real-time prediction of OSA episode onsets. Previous attempts at OSA prediction are limited to capturing the nonlinear, nonstationary dynamics of the underlying physiological processes. Methods This paper reports an investigation into heart rate dynamics aiming to predict in real time the onsets of OSA episode before the clinical symptoms appear. The method includes (a) a representation of a transition state space network to characterize dynamic transition of apneic states (b) a Dirichlet-Process Mixture-Gaussian-Process prognostic method for estimating the distribution of the time estimate the remaining time until the onset of an impending OSA episode by considering the stochastic evolution of the normal states to an anomalous (apnea) Results The approach was tested using three datasets including (1) 20 records from 14 OSA subjects in benchmark ECG apnea databases (Physionet.org), (2) records of eight subjects from previous work. The average prediction accuracy (R2) is reported as 0.75%, with 87% of observations within the 95% confidence interval. Estimated risk indicators at 1 to 3 min till apnea onset are reported as 85.8 %, 80.2 %, and 75.5 %, respectively. Conclusion The present prognosis approach can be integrated with wearable devices to facilitate individualized treatments and timely prevention therapies. Support N/A

P4415Long obstructive sleep apneas as a biomarker of atrial fibrillation

Abstract Background Even though obstructive sleep apnea (OSA) is strongly associated with atrial fibrillation (AF), the use of traditional OSA scoring by apnea hypopnea index (AHI) did not result in improved arrhythmia outcomes in recent randomized trials. Longer OSA episodes lead to stronger pro-arrhythmic changes, and whether very long OSA episodes are more prevalent in AF patients remains unknown. Purpose We hypothesized that AF patients with mild-moderate OSA manifest greater percentage of long (&gt;20s), very long (&gt;30s), and extremely long (&gt;40s) OSA episodes, compared to control OSA patients matched to AHI, age and sex. Methods From patients studied with diagnostic polysomnography in our laboratory between 2016 and 2018, we selected 22 patients with mild-moderate untreated OSA of which 11 patients had history of paroxysmal AF and 11 patients did not have any cardiac history. The length, oxygen desaturation, and relationship to neighboring events was manually re-measured in all recorded apnea and hypopnea events. Results In the 22 included patients (age 62.5±9.1 years, AHI 12.8±6.1, 40% female) we recorded 1021 apneas: 508 in the AF group and 513 in the control group. AF patients had longer apneas compared to the patients without AF history (mean length 28.7±11.7s vs. 23.3±9.9s; p&lt;0.0001). The proportion of apneas that were long (&gt;20s), very long (&gt;30s), and extremely long (&gt;40s) was greater in the AF group as compared to the control (p=0.0039, p=0.0215, p=0.0104, respectively; see figure). The acute oxygen saturation drops (&gt;2%) during apneas were comparable between the AF group and control groups (p=0.13), but the long (&gt;20s) apneas were prone to greater oxygen desaturations. Length of Apneas Conclusions While traditional scoring of OSA focuses on episodes lasting &gt;10s, our data newly show that longer durations of OSA events are particularly prevalent in AF patients. These results, combined with recent mechanistic studies showing that longer apneas exert greater pro-arrhythmic effect on atrial conduction, suggest that novel scoring of OSA placing more weight on longer apneas should be explored, especially when screening and titrating OSA therapy in patients at risk of AF.

Nocturnal Desaturation Early After Delivery: Impact of Delivery Type and the Beneficial Effects of Fowler’s Position

(Br J Anaesth. 2019;122:e64–e66) The authors of the present study previously reported that 20% of women experience obstructive sleep apnea episodes in the immediate postpartum period. They have also found that women sleeping in a 45-degree elevated upper body position, rather than supine, may have significantly reduced apnea-hypopnea indices. Subsequently, in this article, the authors reported on their continuing investigation, which evaluates the impact of delivery type on nocturnal oxygenation and the potential influence of elevated upper body position.

Evolution-based configuration optimization of a Deep Neural Network for the classification of Obstructive Sleep Apnea episodes

Abstract Deep Neural Networks (DNNs) may be very effective for the classification over highly-sized data sets, especially in the medical domain, where the recognition of the occurrence of a specific event related to a disease is of high importance. Unfortunately, DNNs suffer from the drawback that a good set of values for their configuration hyper-parameters must be found. Currently, this is done through the use of either trial-and-error methods or sampling-based ones. In this paper we propose a new approach to find the most suitable structure for a DNN used for a classification problem in terms of achievement of the highest classification accuracy. This approach is based on a distributed version of Differential Evolution (DE), a variety of an Evolutionary Algorithm. To evaluate the approach, in this paper we investigate this issue with reference to Obstructive Sleep Apnea (OSA). OSA is an important medical problem consisting of episodes taking place during night in which a subject stops breathing due to a constriction of the upper airways. This deteriorates the quality of life and may have dangerous, and even lethal, consequences on both short and long term. An accurate classification is a very crucial step for the OSA treatment, because understanding automatically that a subject is experiencing such an episode may be decisive if prompt medical action is needed. In our experiments, classification takes place on a data set in which each item contains the values of 17 Heart Rate Variability parameters, extracted from ElectroCardiography signals, and the annotation of OSA events. We have extracted this data set from the real-world Sleep Heart Health Study database. The results obtained by the distributed DE are compared against those of the Grid Search as well as against those achieved by 13 well-known classification tools. The use of a distributed DE version turns out to be very effective in automatically obtaining DNN structures with higher classification accuracy with respect to Grid Search (72.95% versus 72.61%), and allows saving a high amount of time (three hours as opposed to 65 h and 40 min). Moreover, the proposed method outperforms in terms of higher accuracy all the other classifiers investigated, as it is evidenced also by statistical analysis. Numerically, the runner-up, i.e., JRip, achieves as its best value 72.01% and 71.50% on average over 25 runs, both values being lower than 72.95% and 72.74% obtained by our dDE.

Associations Between Characteristics of Obstructive Sleep Apnea and Nocturnal Blood Pressure Surge.

Research suggests that oxygen desaturation and sleep stage during obstructive sleep apnea (OSA) are related to the magnitude of high blood pressure (BP) in a laboratory setting. However, in a clinical setting, these associations have not been well studied. We used a noninvasive oscillometric BP measurement device to investigate the association between oxygen-triggered BP levels at the end of each OSA episode and the characteristics of the preceding OSA episode. In 42 newly diagnosed OSA patients (average age, 63.5±12.5 years; average apnea-hypopnea index, 32.6±18.2 per hour), 258 BP measurements were obtained at the end of OSA episodes. Hypoxia-peak systolic BP (SBP), defined as the maximum oxygen-triggered SBP value, was significantly higher in rapid eye movement sleep (144.9±19.9 mm Hg) than in non-rapid eye movement stage 1 sleep (129.5±15.1 mm Hg; P<0.001) and non-rapid eye movement stage 2 sleep (129.4±14.7 mm Hg; P<0.001). In a multivariate-linear mixed model, the lowest oxygen saturation percentage during each OSA episode was associated with increased hypoxia-peak SBP (-0.501 mm Hg; P<0.001), nocturnal SBP surge (-0.395 mm Hg; P<0.001), defined as the difference between the hypoxia-peak SBP and the mean nocturnal SBP, and maximum value of SBP surge (-0.468 mm Hg; P<0.001), defined as the difference between the hypoxia-peak SBP and the minimum nocturnal SBP independent of sleep stage. These values were not associated with the duration of each OSA episode. The contribution of rapid eye movement sleep and severe oxygen desaturation to OSA-related BP elevation measured with a noninvasive oscillometric method was determined in a clinical setting.

Associations of Obstructive Sleep Apnea With Atrial Fibrillation and Continuous Positive Airway Pressure Treatment

Obstructive sleep apnea (OSA) is the most common clinically significant breathing abnormality during sleep. It is highly prevalent among patients with atrial fibrillation (AF), and it promotes arrhythmogenesis and impairs treatment efficacy. The prevalence of OSA ranges from 3% to 49% in population-based studies and from 21% to 74% in patients with AF. Diagnosis and treatment of OSA in patients with AF requires a close interdisciplinary collaboration between electrophysiologists, cardiologists, and sleep specialists. Because the prevalence of OSA is high in patients with AF and most do not report daytime sleepiness, sleep-study evaluation may be reasonable for patients being considered for rhythm control strategy. Acute, transient apnea-associated atrial electrophysiological changes and increased occurrence of AF triggers associated with short episodes of intermittent deoxygenation and reoxygenation, intrathoracic pressure changes during obstructed breathing efforts, and sympathovagal activation combine to create a stimulus for AF triggers and a complex and dynamic substrate for AF during sleep. Repeated episodes of long-term OSA are eventually associated with structural remodeling and changes in electrical conduction in the atrium. Observational data suggest OSA reduces the efficacy of catheter-based and pharmacological antiarrhythmic therapy. Nonrandomized studies have shown that treatment of OSA by continuous positive airway pressure can help to maintain a sinus rhythm after electrical cardioversion and catheter ablation in patients with AF. However, it remains unclear which sleep apnea metric should be used to determine severity and guide such treatment in patients with AF. Data from nonrandomized studies of patients with AF suggest that treatment of OSA by continuous positive airway pressure may help to maintain sinus rhythm after electrical cardioversion and improve catheter ablation success rates. Randomized clinical trials are needed to confirm the association between OSA and AF the benefits of treatment of OSA and the need for and cost-effectiveness of routine OSA screening and treatment.

0606 WEARABLE INNOVATION IN SLEEP: DIAGNOSIS AND TREATMENT OF OBSTRUCTIVE SLEEP APNEA

According to the World Health Organization, Obstructive Sleep Apnea (OSA) affects more than 100 million lives worldwide, with a disturbing 80% of undiagnosed cases. For the diagnosis of OSA, Polysomnography (PSG) is considered the gold standard, however, the system is severely handicapped by its high cost (can exceed $10,000 per night along with cost of technicians and physicians), long wait times for scheduling (2–8 months), uncomfortable testing procedure, and unfamiliar testing environment. In this work, we aim at developing a low-cost, and easy to use home sleep testing device with minimum wire configuration and near clinical equivalence with the PSG system. Further, we are working towards the development of a mechanical simulator system to reverse the imminent OSA episodes based on the early prediction. Our device includes a sleep pillow with the electronics embedded inside it. A reflective type poly plethysmography signal is measured from the neck which is used to compute the heart rate, breath rate and SpO2 signals. These signals are then used as an input to our novel prediction algorithm which can predict the apnea episodes 1–3 minutes ahead with more that 90% accuracy. Two mechanical motors are attached to the pillow which can simulate the neck muscle and reverse apnea episodes. We have begun human subject testing with elderly and obese OSA and healthy control. Our device can do real-time analysis and prediction continuously for 9 hours with great user comfort. Further, the breath rate and heart rate was calculated real-time and has an average difference of 2.27 bpm and 0.31 bpm respectively compared to the PSG system. Our device is a stand-alone solution for real-time wireless OSA monitoring. Given the fact that OSA diagnosis by PSG at sleep centers can be really time-consuming and costly, our device being 10 times cheaper, comfortable and available for at home use on a daily basis can bring great value to the OSA market. This research was supported by NSF PFI-AIR-TT (National Science Foundation: Partnership for Innovation: Accelerating Innovation Research-Technology Transfer)

A Review of Obstructive Sleep Apnea, Shift Work, Gender

The purpose of the review is to make connections between obstructive sleep apnea (OSA) and shift work while giving special attention to the factor of gender and rapid eye movement sleep. Obstructive sleep apnea is a common sleep disorder that has various detrimental effects on health and cognitive functioning. The prevalence and symptoms of OSA appear to be gender specific. The current clinical guideline has not yet included the evaluation of fatigue, the common symptoms among women with OSA, which may lead to an under diagnosis of OSA among women. Rapid eye movement sleep is associated with more severe OSA episodes. Shift work has a similar range of effects on health and cognitive functioning, however, it affects workers through both sleep disturbance and circadian disruption. Gender specific effects have also been observed among shift workers. Night shift interacts with REM sleep and may lead to a higher risk of cardiovascular disease. Finally, we proposed the question, “Is there a difference in the REM sleep of male and female night shift workers with OSA,” and “How is cognitive functioning of these two groups affected by the interaction of OSA and shift work?”.

Nonlinear Dynamics Forecasting of Obstructive Sleep Apnea Onsets.

Recent advances in sensor technologies and predictive analytics are fueling the growth in point-of-care (POC) therapies for obstructive sleep apnea (OSA) and other sleep disorders. The effectiveness of POC therapies can be enhanced by providing personalized and real-time prediction of OSA episode onsets. Previous attempts at OSA prediction are limited to capturing the nonlinear, nonstationary dynamics of the underlying physiological processes. This paper reports an investigation into heart rate dynamics aiming to predict in real time the onsets of OSA episode before the clinical symptoms appear. A prognosis method based on a nonparametric statistical Dirichlet-Process Mixture-Gaussian-Process (DPMG) model to estimate the transition from normal states to an anomalous (apnea) state is utilized to estimate the remaining time until the onset of an impending OSA episode. The approach was tested using three datasets including (1) 20 records from 14 OSA subjects in benchmark ECG apnea databases (Physionet.org), (2) records of 10 OSA patients from the University of Dublin OSA database and (3) records of eight subjects from previous work. Validation tests suggest that the model can be used to track the time until the onset of an OSA episode with the likelihood of correctly predicting apnea onset in 1 min to 5 mins ahead is 83.6 ± 9.3%, 80 ± 8.1%, 76.2 ± 13.3%, 66.9 ± 15.4%, and 61.1 ± 16.7%, respectively. The present prognosis approach can be integrated with wearable devices, enhancing proactive treatment of OSA and real-time wearable sensor-based of sleep disorders.

Finite An Early Warning Algorithm to Predict Obstructive Sleep Apnea (OSA) Episodes

Finite An Early Warning Algorithm to Predict Obstructive Sleep Apnea (OSA) Episodes