0579 Non Intrusive and Unattended Sleep Analyzer Effectively Screens Patients Suspected of Sleep Apnea: A Comparison With Polysomnography

Abstract Introduction Sleep Apnea Syndrome (SAS) is largely underdiagnosed due to the cost and availability of Polysomnography (PSG). We aimed at evaluating the diagnosis of SAS with the WITHINGS Sleep Apnea Detector (SAD), a non-intrusive pressure and sound sensor placed under the mattress. Methods 118 patients (67 F, 49 years, BMI 33kg/m²) suspected of SAS had an in-laboratory PSG together with Sleep Apnea Detector. From the pressure signal, Sleep Apnea Detector derives respiratory and cardiac signals and movements. From the microphone, snoring and snorting are detected. These features are used to detect sleep periods with a Random Forest classifier and apnea and hypopnea events with a Convolutional Neural Network. The Total Sleep Time (TST) and Apnea Hypopnea Index (AHI) deduced (TSTsad, AHIsad) are compared with the PSG results scored according to AASM rules (TSTpsg, AHIpsg). AHI and TST were compared using bias and Mean Absolute Error (MAE). Sensitivity, specificity, likelihood ratios (LR) and AUROC were calculated for AHI thresholds of 15 and 30/hr. Results The average (SD) TSTpsg was 367 (61) minutes. Sleep Apnea Detector overestimated TST by 25 minutes, 7.0% of the average duration in the sample. The precision is acceptable, with a MAE=53 minutes. Average AHIpsg was 32.5 (30.1) and AHIsad 32.8 (29.9). The bias was 0.3 (95% CI [-2.7, 3.3]), MAE=10.3. The sensitivity (Se15) and specificity (Sp15) and their 95% confidence intervals were Se15=88.0% [79.0, 94.1] and Sp15=88.6% [73.3, 96.8]. Positive and negative LR were respectively LR+15=7.70 and LR-15=0.136. AUROC15=0.926. At the 30 threshold, Se30=86.0% [73.3, 94.2] and Sp30=91.2% [81.8, 96.7]. Positive and negative LR were LR+30=9.75 and LR-30=0.153. AUROC30=0.954. Conclusion Sleep Apnea Detector has excellent sensitivity and specificity, low bias and good precision. Thus it can be used as an unattended SAS screening device in patients likely to suffer from SAS. Support WITHINGS

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Morning Headache as an Obstructive Sleep Apnea-Related Symptom among Sleep Clinic Patients—A Cross-Section Analysis

Brain Sciences ◽

10.3390/brainsci10010057 ◽

2020 ◽

Vol 10 (1) ◽

pp. 57

Author(s):

Jakub Spałka ◽

Konrad Kędzia ◽

Wojciech Kuczyński ◽

Aleksandra Kudrycka ◽

Aleksandra Małolepsza ◽

...

Keyword(s):

Obstructive Sleep Apnea ◽

Sleep Apnea ◽

Sleep Apnea Syndrome ◽

Sleep Time ◽

Apnea Hypopnea Index ◽

Blood Oxygen Saturation ◽

Arousal Index ◽

Unrefreshing Sleep ◽

Obstructive Sleep ◽

Morning Headache

Morning headache is considered to be a symptom of obstructive sleep apnea syndrome (OSAS). Despite not being as common as excessive daytime sleepiness or unrefreshing sleep, it can similarly impair everyday activities. The aim of the present study was to evaluate the prevalence of and factors associated with morning headaches (MH) among patients referred for polysomnography due to suspected OSAS. This is a retrospective study on 1131 patients who underwent polysomnography between 2013 and 2015. Morning headaches (MH) were reported in 29% of them. In a logistic regression model, a rise in the n probability of MH was associated with female sex (odds ratio, OR, 1.38, 95% confidence interval, CI, 1.08–1.75), history of hypertension (OR 1.25, 95% CI 1.06–1.46), complaint on unrefreshing sleep (OR 1.42, 95% CI 1.19–1.70), choking at night (OR 1.25, 95% CI 1.05–1.49), and fall in total sleep time (OR 0.872 per each hour, 95% CI 0.76–0.99). The risk between MH and apnea–hypopnea index, blood oxygen saturation parameters or arousal index was found to be statistically insignificant. There is a lack of evidence that MH is associated with the severity of OSAS or nocturnal hypoxemia.

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Detecting Apnea/Hypopnea Events Time Location from Sound Recordings for Patients with Severe or Moderate Sleep Apnea Syndrome

Applied Sciences ◽

10.3390/app11156888 ◽

2021 ◽

Vol 11 (15) ◽

pp. 6888

Author(s):

Georgia Korompili ◽

Lampros Kokkalas ◽

Stelios A. Mitilineos ◽

Nicolas-Alexander Tatlas ◽

Stelios M. Potirakis

Keyword(s):

Sleep Apnea ◽

Sleep Apnea Syndrome ◽

Apnea Hypopnea Index ◽

Event Time ◽

Severity Estimation ◽

Apnea Duration ◽

Respiratory Events ◽

Moderate Sensitivity ◽

Apnea Syndrome

The most common index for diagnosing Sleep Apnea Syndrome (SAS) is the Apnea-Hypopnea Index (AHI), defined as the average count of apnea/hypopnea events per sleeping hour. Despite its broad use in automated systems for SAS severity estimation, researchers now focus on individual event time detection rather than the insufficient classification of the patient in SAS severity groups. Towards this direction, in this work, we aim at the detection of the exact time location of apnea/hypopnea events. We particularly examine the hypothesis of employing a standard Voice Activity Detection (VAD) algorithm to extract breathing segments during sleep and identify the respiratory events from severely altered breathing amplitude within the event. The algorithm, which is tested only in severe and moderate patients, is applied to recordings from a tracheal and an ambient microphone. It proves good sensitivity for apneas, reaching 81% and 70.4% for the two microphones, respectively, and moderate sensitivity to hypopneas—approx. 50% were identified. The algorithm also presents an adequate estimator of the Mean Apnea Duration index—defined as the average duration of the detected events—for patients with severe or moderate apnea, with mean error 1.7 s and 3.2 s for the two microphones, respectively.

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Analysis of nocturnal desaturation waveforms using algorithms in patients with idiopathic pulmonary fibrosis

Sleep And Breathing ◽

10.1007/s11325-021-02456-3 ◽

2021 ◽

Author(s):

Yuichiro Yasuda ◽

Tatsuya Nagano ◽

Shintaro Izumi ◽

Mina Yasuda ◽

Kosuke Tsuruno ◽

...

Keyword(s):

Sleep Apnea ◽

Idiopathic Pulmonary Fibrosis ◽

Pulmonary Fibrosis ◽

Diagnostic Algorithm ◽

Sleep Time ◽

Periodic Pattern ◽

Apnea Hypopnea Index ◽

Apnea Test ◽

Eligibility Criteria ◽

Obstructive Sleep

Abstract Purpose Sleep-disordered breathing is recognized as a comorbidity in patients with idiopathic pulmonary fibrosis (IPF). Among them, nocturnal hypoxemia has been reported to be associated with poor prognosis and disease progression. We developed a diagnostic algorithm to classify nocturnal desaturation from percutaneous oxygen saturation (SpO2) waveform patterns: sustained pattern, periodic pattern, and intermittent pattern. We then investigated the prevalence of nocturnal desaturation and the association between the waveform patterns of nocturnal desaturation and clinical findings of patients with IPF. Methods We prospectively enrolled patients with IPF from seven general hospitals between April 2017 and March 2020 and measured nocturnal SpO2 and nasal airflow by using a home sleep apnea test. An algorithm was used to classify the types of nocturnal desaturation. We evaluated the association between sleep or clinical parameters and each waveform pattern of nocturnal desaturation. Results Among 60 patients (47 men) who met the eligibility criteria, there were 3 cases with the sustained pattern, 49 cases with the periodic pattern, and 41 cases with the intermittent pattern. Lowest SpO2 during sleep and total sleep time spent with SpO2 < 90% were associated with the sustained pattern, and apnea–hypopnea index was associated with the intermittent pattern. Conclusion We demonstrated the prevalence of each waveform and association between each waveform and sleep parameters in patients with IPF. This classification algorithm may be useful to predict the degree of hypoxemia or the complication of obstructive sleep apnea.

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Altered K-complex morphology during sustained inspiratory airflow limitation is associated with next-day lapses in vigilance in obstructive sleep apnea

SLEEP ◽

10.1093/sleep/zsab010 ◽

2021 ◽

Author(s):

Ankit Parekh ◽

Korey Kam ◽

Anna E Mullins ◽

Bresne Castillo ◽

Asem Berkalieva ◽

...

Keyword(s):

Obstructive Sleep Apnea ◽

Sleep Apnea ◽

Spectral Characteristics ◽

Sleep Time ◽

Airflow Limitation ◽

Apnea Hypopnea Index ◽

Complex Morphology ◽

Obstructive Sleep ◽

Inspiratory Airflow Limitation ◽

Psychomotor Vigilance

Abstract Study Objectives Determine if changes in K-complexes associated with sustained inspiratory airflow limitation (SIFL) during N2 sleep are associated with next-day vigilance and objective sleepiness. Methods Data from thirty subjects with moderate-to-severe obstructive sleep apnea who completed three in-lab polysomnograms: diagnostic, on therapeutic continuous positive airway pressure (CPAP), and on suboptimal CPAP (4 cmH2O below optimal titrated CPAP level) were analyzed. Four 20-min psychomotor vigilance tests (PVT) were performed after each PSG, every 2 h. Changes in the proportion of spontaneous K-complexes and spectral characteristics surrounding K-complexes were evaluated for K-complexes associated with both delta (∆SWAK), alpha (∆αK) frequencies. Results Suboptimal CPAP induced SIFL (14.7 (20.9) vs 2.9 (9.2); %total sleep time, p < 0.001) with a small increase in apnea–hypopnea index (AHI3A: 6.5 (7.7) vs 1.9 (2.3); p < 0.01) versus optimal CPAP. K-complex density (num./min of stage N2) was higher on suboptimal CPAP (0.97 ± 0.7 vs 0.65±0.5, #/min, mean ± SD, p < 0.01) above and beyond the effect of age, sex, AHI3A, and duration of SIFL. A decrease in ∆SWAK with suboptimal CPAP was associated with increased PVT lapses and explained 17% of additional variance in PVT lapses. Within-night during suboptimal CPAP K-complexes appeared to alternate between promoting sleep and as arousal surrogates. Electroencephalographic changes were not associated with objective sleepiness. Conclusions Sustained inspiratory airflow limitation is associated with altered K-complex morphology including the increased occurrence of K-complexes with bursts of alpha as arousal surrogates. These findings suggest that sustained inspiratory flow limitation may be associated with nonvisible sleep fragmentation and contribute to increased lapses in vigilance.

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Endothelial dysfunction in obstructive sleep apnea patients

Sleep And Breathing ◽

10.1007/s11325-021-02382-4 ◽

2021 ◽

Author(s):

Michał Harańczyk ◽

Małgorzata Konieczyńska ◽

Wojciech Płazak

Keyword(s):

Obstructive Sleep Apnea ◽

Sleep Apnea ◽

Endothelial Dysfunction ◽

Right Ventricular ◽

Contractile Function ◽

Sleep Apnea Syndrome ◽

Apnea Hypopnea Index ◽

Endothelin 1 ◽

Obstructive Sleep

Abstract Purpose Obstructive sleep apnea syndrome (OSAS) is an independent risk factor for cardiovascular diseases. The aim of the study was to assess the influence of OSAS on endothelial dysfunction and thrombosis biomarkers and to evaluate the effect of treatment with continuous positive airway pressure (CPAP) on biomarker levels. Methods NT-proBNP, sICAM-1, endothelin-1, von Willebrand factor, D-dimers, and thrombin-antithrombin complex (TAT) were measured in 50 patients diagnosed with moderate-to-severe OSAS. All patients underwent transthoracic echocardiography, and 38 months after the inclusion, 16 CPAP users and 22 non-CPAP users were reassessed. Results Sleep-related indices of apnea-hypopnea index (AHI) and mean SpO2 were associated with higher sICAM-1 levels (AHI < 30: 7.3 ± 4.7 vs. AHI ≥ 30: 19.5 ± 19.4 mg/ml, p = 0.04; SpO2 ≥ 90%: 11.9 ± 9.3 vs. SpO2 < 90%: 23.6 ± 25.8, p = 0.04). sICAM-1 levels were significantly higher in obese patients, particularly with BMI ≥ 40. Plasma levels of TAT were significantly correlated with the increased right ventricular size (right ventricular diameter ≤ 37 mm: 0.86 ± 0.70 vs. > 37 mm: 1.96 ± 1.20 ng/ml, p = 0.04). Endothelin-1 levels were higher in patients with decreased right ventricular function (right ventricle TDI-derived S′ ≥ 12 cm/s: 11.5 ± 10.9 vs. < 12 cm/s: 26.0 ± 13.2 pg/ml, p = 0.04). An increase in NT-proBNP was related to impaired parameters of the right ventricular contractile function. There were no correlations between long-term CPAP therapy and the levels of biomarkers. Conclusion Severe OSAS influences endothelial damage as manifested by an increase in sICAM-1 levels. Changes in right ventricular structure and function, observed mainly in patients with higher TAT and endothelin-1 levels, are also manifested by an increase in NT-proBNP levels. Long-term CPAP treatment does not seem to influence biomarkers in patients with moderate-to-severe OSAS, which may help to explain the lack of influence of CPAP on cardiovascular risk reduction.

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Effect of a Graduated Walking Program on the Severity of Obstructive Sleep Apnea Syndrome. A Randomized Clinical Trial

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17176334 ◽

2020 ◽

Vol 17 (17) ◽

pp. 6334

Author(s):

Antonio Jurado-García ◽

Guillermo Molina-Recio ◽

Nuria Feu-Collado ◽

Ana Palomares-Muriana ◽

Adela María Gómez-González ◽

...

Keyword(s):

Obstructive Sleep Apnea ◽

Sleep Apnea ◽

Obstructive Sleep Apnea Syndrome ◽

Sleep Apnea Syndrome ◽

Intervention Group ◽

Exercise Program ◽

Density Lipoprotein ◽

Apnea Hypopnea Index ◽

Obstructive Sleep ◽

Apnea Syndrome

Background: Obstructive sleep apnea syndrome (OSAS) is a common disease. The objective of this research was to determine the effectiveness of a graduated walking program in reducing the apnea–hypopnea index number in patients with obstructive sleep apnea syndrome (OSAS). Methods: A randomized controlled clinical trial with a two-arm parallel in three tertiary hospitals was carried out with seventy sedentary patients with moderate to severe OSAS. Twenty-nine subjects in each arm were analyzed by protocol. The control group received usual care, while usual care and an exercise program based on progressive walks without direct supervision for 6 months were offered to the intervention group. Results: The apnea–hypopnea index decreased by six points in the intervention group, and improvements in oxygen desaturation index, total cholesterol, and Low-Density Lipoprotein of Cholesterol (LDL-c) were observed. A higher decrease in sleep apnea–hypopnea index (45 ± 20.6 vs. 34 ± 26.3/h; p = 0.002) was found in patients with severe vs. moderate OSAS, as well as in oxygen desaturation index from baseline values (43.3 vs. 34.3/h; p = 0.046). Besides, High-Density Lipoprotein of Cholesterol (HDL-c) values showed a higher increase in the intervention group (45.3 vs. 49.5 mg/dL; p = 0.009) and also, a higher decrease in LDL-c was found in this group (141.2 vs. 127.5 mg/dL; p = 0.038). Conclusion: A home physical exercise program is a useful and viable therapeutic measure for the management of OSAS.

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Cardiac arrhythmias and conduction disturbances in the obstructive sleep apnea syndrome

In a good rythm ◽

10.5604/01.3001.0012.0392 ◽

2018 ◽

Vol 2 (47) ◽

pp. 10-15

Author(s):

Danuta Łoboda ◽

Karolina Simionescu ◽

Anna Szajerska-Kurasiewicz ◽

Dorota Lasyk ◽

Grzegorz Jarosiński ◽

...

Keyword(s):

Obstructive Sleep Apnea ◽

Sleep Apnea ◽

Cardiac Arrhythmias ◽

Sleep Apnea Syndrome ◽

The Body ◽

Apnea Hypopnea Index ◽

Premature Ventricular Contractions ◽

Mortality And Morbidity ◽

Conduction Disturbances ◽

Obstructive Sleep

Cardiac arrhythmias during sleep are reported in almost half of the population suffering from obstructive sleep apnea (OSA). The most common are bradyarrhythmias and atrial fibrillation whereas premature ventricular contractions and nonsustained ventricular tachycardia are less frequent. The risk of arrhythmia is proportional to the body mass index (BMI), number of respiratory events per hour of sleep described with apnea/hypopnea index (AHI) and the level of oxygen desaturation during these episodes. Continuous positive airway pressure (CPAP) treatment in OSA reduces the incidence of cardiac arrhythmias therefore reduce mortality and morbidity from cardiovascular disease.

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Detection of obstructive sleep apnea using Belun Sleep Platform wearable with neural network-based algorithm and its combined use with STOP-Bang questionnaire

PLoS ONE ◽

10.1371/journal.pone.0258040 ◽

2021 ◽

Vol 16 (10) ◽

pp. e0258040

Author(s):

Eric Yeh ◽

Eileen Wong ◽

Chih-Wei Tsai ◽

Wenbo Gu ◽

Pai-Lien Chen ◽

...

Keyword(s):

Neural Network ◽

Obstructive Sleep Apnea ◽

Sleep Apnea ◽

Physiological Data ◽

Apnea Hypopnea Index ◽

Clinical Practices ◽

Sleep Study ◽

Link Type ◽

Obstructive Sleep ◽

Sensitivity Specificity

Many wearables allow physiological data acquisition in sleep and enable clinicians to assess sleep outside of sleep labs. Belun Sleep Platform (BSP) is a novel neural network-based home sleep apnea testing system utilizing a wearable ring device to detect obstructive sleep apnea (OSA). The objective of the study is to assess the performance of BSP for the evaluation of OSA. Subjects who take heart rate-affecting medications and those with non-arrhythmic comorbidities were included in this cohort. Polysomnography (PSG) studies were performed simultaneously with the Belun Ring in individuals who were referred to the sleep lab for an overnight sleep study. The sleep studies were manually scored using the American Academy of Sleep Medicine Scoring Manual (version 2.4) with 4% desaturation hypopnea criteria. A total of 78 subjects were recruited. Of these, 45% had AHI < 5; 18% had AHI 5–15; 19% had AHI 15–30; 18% had AHI ≥ 30. The Belun apnea-hypopnea index (bAHI) correlated well with the PSG-AHI (r = 0.888, P < 0.001). The Belun total sleep time (bTST) and PSG-TST had a high correlation coefficient (r = 0.967, P < 0.001). The accuracy, sensitivity, specificity in categorizing AHI ≥ 15 were 0.808 [95% CI, 0.703–0.888], 0.931 [95% CI, 0.772–0.992], and 0.735 [95% CI, 0.589–0.850], respectively. The use of beta-blocker/calcium-receptor antagonist and the presence of comorbidities did not negatively affect the sensitivity and specificity of BSP in predicting OSA. A diagnostic algorithm combining STOP-Bang cutoff of 5 and bAHI cutoff of 15 events/h demonstrated an accuracy, sensitivity, specificity of 0.938 [95% CI, 0.828–0.987], 0.944 [95% CI, 0.727–0.999], and 0.933 [95% CI, 0.779–0.992], respectively, for the diagnosis of moderate to severe OSA. BSP is a promising testing tool for OSA assessment and can potentially be incorporated into clinical practices for the identification of OSA. Trial registration: ClinicalTrial.org NCT03997916 https://clinicaltrials.gov/ct2/show/NCT03997916?term=belun+ring&draw=2&rank=1

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Abstract TMP55: Polysomnographic and Sleep-related Variables Associated to Leukoaraiosis in Patients with Obstructive Sleep Apnea

Stroke ◽

10.1161/str.48.suppl_1.tmp55 ◽

2017 ◽

Vol 48 (suppl_1) ◽

Author(s):

Kevin R Duque ◽

Brian Villafuerte ◽

Fiorella Adrianzen ◽

Rodrigo Zamudio ◽

Andrea Mendiola ◽

...

Keyword(s):

Obstructive Sleep Apnea ◽

Logistic Regression ◽

Sleep Apnea ◽

Multinomial Logistic Regression ◽

Sleep Time ◽

Cross Sectional Study ◽

Apnea Hypopnea Index ◽

Cross Sectional ◽

Obstructive Sleep ◽

Medical Histories

Introduction: Obstructive sleep apnea (OSA) is a biological plausible risk factor for leukoaraiosis (LA). We tested the hypothesis that polysomnographic (PSG) and sleep-related variables are associated to LA in OSA patients. Methods: Cross-sectional study in which PSG records, medical histories and brain 1.5T MRI were collected from all consecutive patients who had attended a Sleep Medicine Center between 2009-2014. LA was graded from 0 to 9 with the ’Atherosclerosis Risk In Communities’ study scale. OSA was defined by The International Classification of Sleep Disorders, 2014, and its severity categorizing according to apnea-hypopnea index (AHI, <15 mild, 15 to <30 moderate, 30 to <45 severe and ≥45 very severe). A multinomial logistic regression was performed to describe the association between OSA severity and LA (divided into 2 groups: mild-to-moderate LA and non-to-minimal LA). The covariates for all regression models were age, gender, BMI, hypertension, ischemic stroke, myocardial infarction, diabetes and pack-year of smoking. Results: From 82 OSA patients (77% male; mean age 58±9 years, range 19-91), 54 (66%) had LA. Mild-to-moderate LA was found in 13 patients (8 mild and 5 moderate LA) and non-to-minimal LA in 69 (41 minimal and 28 non LA). Spearman’s correlation coefficient between AHI and LA grade was 0.41 (p<0.001). Furthermore, the higher OSA severity, the higher LA severity (p<0.001, for Jonckheere-Terpstra test for ordered alternatives). In the multinomial logistic regression model adjusted for cofounders, severe OSA patients had higher risk for mild or moderate LA (HR 12.8, 95% IC 1.2-141) compared to mild-to-moderate OSA patients. Additionally, self-reported habitual sleep duration from 7 to 9 hours (HR 0.36, 90% IC 0.14-0.90) and proportion of time in apnea/hypopnea over total sleep time (HR 1.04 for one unit increase, 90% IC 1.01-1.08) could be associated with the presence of LA (adjusted only for age and gender). In a multiple regression analysis with all the aforementioned variables, age (p=0.002), diabetes (p=0.003), and OSA severity (p=0.04) were predictors of the presence of LA. Conclusion: Patients with severe OSA had higher risk for mild to moderate LA when compared to patients with mild or moderate OSA.

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