Validation of the Nox-T3 Portable Monitor for Diagnosis of Obstructive Sleep Apnea in Patients With Chronic Obstructive Pulmonary Disease

Telemedicine management of obstructive sleep apnea disorder in China: a randomized, controlled, non-inferiority trial

PURPOSE

Previous studies assessed different components of telemedicine management pathway for OSA instead of the whole pathway. This randomized, controlled, and non-inferiority trial aimed to assess whether telemedicine management is clinically inferior to in-person care in China.

METHODS

Adults suspected of OSA were randomized to telemedicine (web-based questionnaires, self-administered home sleep apnea test [HSAT], automatically adjusting positive airway pressure [APAP], and video-conference visits) or in-person management (paper questionnaires, in-person HSAT set-up, APAP, and face-to-face visits). Participants with an apnea-hypopnea index (AHI) ≥ 15 events/hour received APAP for 3 months. The non-inferiority analysis was based on the change in Functional Outcomes of Sleep Questionnaire (FOSQ) score and APAP adherence. Cost-effectiveness analysis was performed.

RESULTS

In the modified intent-to-treat analysis set (n = 111 telemedicine, 111 in-person), FOSQ scores improved 1.73 (95% confidence interval [CI], 1.31-2.14) points with telemedicine and 2.05 (1.64-2.46) points with in-person care. The lower bound of the one-sided 95% non-inferiority CI for the difference in change between groups of - 0.812 was larger than the non-inferiority threshold of - 1. APAP adherence at 3 months was 243.3 (223.1-263.5) minutes/night for telemedicine and 241.6 (221.3-261.8) minutes/night for in-person care. The lower bound of the one-sided 95% non-inferiority CI of - 22.2 min/night was higher than the non-inferiority delta of - 45 min/night. Telemedicine had lower total costs than in-person management (CNY 1482.7 ± 377.2 vs. 1912.6 ± 681.3; p < 0.0001), driven by patient costs, but no significant difference in QALYs.

CONCLUSIONS

Functional outcomes and adherence were not clinically inferior in patients managed by a comprehensive telemedicine approach compared to those receiving in-person care in China.

CLINICAL TRIAL REGISTRATION

https://www.chictr.org.cn , Registration number ChiCTR2000030546. Retrospectively registered on March 06, 2020.

Noninvasive monitoring technologies to identify discomfort and distressing symptoms in persons with limited communication at the end of life: a scoping review

BACKGROUND

Discomfort and distressing symptoms are common at the end of life, while people in this stage are often no longer able to express themselves. Technologies may aid clinicians in detecting and treating these symptoms to improve end-of-life care. This review provides an overview of noninvasive monitoring technologies that may be applied to persons with limited communication at the end of life to identify discomfort.

METHODS

A systematic search was performed in nine databases, and experts were consulted. Manuscripts were included if they were written in English, Dutch, German, French, Japanese or Chinese, if the monitoring technology measured discomfort or distressing symptoms, was noninvasive, could be continuously administered for 4 hours and was potentially applicable for bed-ridden people. The screening was performed by two researchers independently. Information about the technology, its clinimetrics (validity, reliability, sensitivity, specificity, responsiveness), acceptability, and feasibility were extracted.

RESULTS

Of the 3,414 identified manuscripts, 229 met the eligibility criteria. A variety of monitoring technologies were identified, including actigraphy, brain activity monitoring, electrocardiography, electrodermal activity monitoring, surface electromyography, incontinence sensors, multimodal systems, and noncontact monitoring systems. The main indicators of discomfort monitored by these technologies were sleep, level of consciousness, risk of pressure ulcers, urinary incontinence, agitation, and pain. For the end-of-life phase, brain activity monitors could be helpful and acceptable to monitor the level of consciousness during palliative sedation. However, no manuscripts have reported on the clinimetrics, feasibility, and acceptability of the other technologies for the end-of-life phase.

CONCLUSIONS

Noninvasive monitoring technologies are available to measure common symptoms at the end of life. Future research should evaluate the quality of evidence provided by existing studies and investigate the feasibility, acceptability, and usefulness of these technologies in the end-of-life setting. Guidelines for studies on healthcare technologies should be better implemented and further developed.

The Overlap Syndrome: A Combination of Chronic Obstructive Pulmonary Disease and Obstructive Sleep Apnea

Chronic obstructive pulmonary disease (COPD) is a severe lung disease that results in persistent and progressively worsening airflow obstruction due to abnormalities in the airway and alveoli. Obstructive sleep apnea (OSA) is a critical condition characterized by obstructive apneas, hypopneas, and respiratory effort-related arousals. These events occur due to the repetitive collapse of the upper airway during sleep, and it is essential to address this condition. These two conditions, when co-occur, are known as overlap syndrome (OS), which is associated with a higher likelihood of morbidity and mortality compared to either condition alone. Effective management of overlap syndrome is critical to maintain normal oxygen levels during sleep and reduce the incidence of hypoxemia and hypoventilation while improving sleep quality. Positive pressure ventilation is a standard technique used to effectively lower hospitalizations, emergency room visits, moderate and severe exacerbations, and related healthcare expenses in patients diagnosed with COPD and OSA. Despite the lack of literature on overlap syndrome, it is imperative to understand that this condition requires prompt and effective management to prevent further complications. Therefore, this review provides a detailed discussion highlighting the importance of proactive measures to manage overlap syndrome.

Prevalence and clinical characteristics of sleep disorders in chronic obstructive pulmonary disease: A systematic review and meta-analysis

BACKGROUND

Sleep disorders, including obstructive sleep apnea (OSA), restless leg syndrome (RLS) and insomnia, are present in chronic obstructive pulmonary disease (COPD) with varied prevalence. The aim of this systematic review and meta-analysis was to investigate prevalence of OSA, RLS and insomnia in patients with COPD and summarize their clinical characteristics.

METHODS

We searched PubMed, Web of Science and Scopus for eligible articles reporting the prevalence of OSA, RLS, and insomnia in COPD patients. The Newcastle‒Ottawa scale was applied for quality assessment. Odds ratios or mean differences with 95 % confidence intervals (CIs) were applied for the overall prevalence calculation and clinical characteristics assessment. Sensitivity analysis, subgroup analysis and meta-regression were conducted to evaluate the heterogeneity of the results.

RESULTS

Sixty articles reporting the prevalence of sleep disorders in patients with COPD were included, and the prevalence of OSA, RLS, and insomnia reached 29.1 %(95%CI 27.2%-30.9 %), 21.6 %(95%CI 11.8%-33.3 %) and 29.5 %(95%CI 16.9%-44.0 %), respectively. COPD patients with OSA were characterized by male sex (OR 1.631 95 % CI: 1.231-2.161), obesity(kg/m2) (MD 4.435, 95 % CI 3.218-5.652), higher Epworth Sleepiness Scale (MD: 3.741, 95 % CI: 0.655-6.828, p = 0.018), better pulmonary function (MD 5.66, 95 % CI 3.546-7.774) and higher risks of hypertension (OR 1.933 95 % CI 1.382-2.70) and diabetes (OR 1.898 95 % CI 1.264-2.849). COPD patients with RLS were associated with a higher Epworth sleepiness scale (ESS) score (MD 3.444, 95 % CI 1.880-5.008) and a longer COPD duration(year) (MD: 3.656, 95 % CI: 2.209-5.103). COPD patients with insomnia were characterized by female sex(OR 0.556, 95%CI 0.545,0.567, p < 0.001).

CONCLUSION

Our study suggests that OSA, RLS and insomnia are common in COPD patients with specific clinical characteristics. Further studies are needed to explore the interactions between COPD and sleep disorders.

Home monitoring for clinically suspected obstructive sleep apnea in pregnancy

STUDY OBJECTIVES

To determine if a home sleep apnea test (HSAT) using a type III portable monitor (PM), Nox-T3 (Nox Medical, Inc., Reykjavik, Iceland), detects obstructive sleep apnea in pregnant women.

METHODS

Ninety-two pregnant women (34.5 ± 4.3 years; gestational age 25.4 ± 8.9 weeks; body mass index 29.9 ± 4.7 kg/m2) with suspected obstructive sleep apnea underwent HSAT with the Nox-T3 PM followed by overnight polysomnography (PSG) and PM recording simultaneously in the laboratory within 1 week. PMs were scored automatically and manually using a 3% criteria and compared with PSGs scored by following guidelines.

RESULTS

Apnea-hypopnea indexes were 8.56 ± 10.42, 8.19 ± 13.79, and 8.71 ± 14.19 events/h on HSAT, in-laboratory PM recording, and PSG (P = .955), respectively. Bland-Altman analysis of the apnea-hypopnea index on PSG vs HSAT showed a mean difference (95% confidence interval) of -0.15 (-1.83, 1.53); limits of agreement (± 2 SD) were -16.26 to 16.56 events/h. Based on a threshold apnea-hypopnea index ≥ 5 events/h, HSAT had 91% sensitivity, 85% specificity, 84% positive-predictive value, and 92% negative-predictive value compared with PSG. When comparing the simultaneous recordings, closer agreement was observed. Automated vs manual analysis of PM showed no significant difference.

CONCLUSIONS

A type III PM had an acceptable failure rate and high diagnostic performance operating as a reasonable alternative for in-laboratory PSG in pregnant women.

CITATION

Wang J, Zhang C, Xu L, et al. Home monitoring for clinically suspected obstructive sleep apnea in pregnancy. J Clin Sleep Med. 2023;19(11):1951-1960.

Interaction of BMI and respiratory status in obstructive sleep apnea, a cross-sectional COPD study

This cross-sectional study of 136 patients with chronic obstructive pulmonary disease (COPD) investigated the mechanism underlying overlap syndrome, defined as coexisting COPD and obstructive sleep apnea (OSA). OSA was defined as a respiratory event index (REI) ≥ 5 events/h, determined using type-3 portable monitors. The mean REI was 12.8 events/h. Most participants (60.1%) had mild OSA (REI: 5-15 events/h). The REI was positively correlated with forced expiratory volume in one second (%FEV1) (r = 0.33, p < 0.001), body mass index (BMI) (r = 0.24, p = 0.005), and fat-free mass index (r = 0.31, p = 0.005), and negatively correlated with residual volume divided by total lung capacity (r = -0.27, p = 0.003). Receiver-operating characteristic curve analysis revealed an optimal BMI cutoff of 21.96 kg/m2 for predicting moderate/severe OSA. A BMI ≥ 21.96 kg/m2 was associated with OSA among participants with %FEV1 ≥ 50%, but not those with %FEV1 < 50%. This study revealed an interaction between airflow limitation and hyperinflation, nutritional status, and OSA.

International Consensus Statement on Obstructive Sleep Apnea

BACKGROUND

Evaluation and interpretation of the literature on obstructive sleep apnea (OSA) allows for consolidation and determination of the key factors important for clinical management of the adult OSA patient. Toward this goal, an international collaborative of multidisciplinary experts in sleep apnea evaluation and treatment have produced the International Consensus statement on Obstructive Sleep Apnea (ICS:OSA).

METHODS

Using previously defined methodology, focal topics in OSA were assigned as literature review (LR), evidence-based review (EBR), or evidence-based review with recommendations (EBR-R) formats. Each topic incorporated the available and relevant evidence which was summarized and graded on study quality. Each topic and section underwent iterative review and the ICS:OSA was created and reviewed by all authors for consensus.

RESULTS

The ICS:OSA addresses OSA syndrome definitions, pathophysiology, epidemiology, risk factors for disease, screening methods, diagnostic testing types, multiple treatment modalities, and effects of OSA treatment on multiple OSA-associated comorbidities. Specific focus on outcomes with positive airway pressure (PAP) and surgical treatments were evaluated.

CONCLUSION

This review of the literature consolidates the available knowledge and identifies the limitations of the current evidence on OSA. This effort aims to create a resource for OSA evidence-based practice and identify future research needs. Knowledge gaps and research opportunities include improving the metrics of OSA disease, determining the optimal OSA screening paradigms, developing strategies for PAP adherence and longitudinal care, enhancing selection of PAP alternatives and surgery, understanding health risk outcomes, and translating evidence into individualized approaches to therapy.

Validation of a portable monitor compared with polysomnography for screening of obstructive sleep apnea in polio survivors

Subjective

Sleep-disordered breathing (SDB) is highly prevalent in polio survivors. Obstructive sleep apnea (OSA) is the most frequent type. Full polysomnography (PSG) is recommended for OSA diagnosis in patients with comorbidities by current practice guidelines, but it is not always accessible. The purpose of this study was to evaluate whether type 3 portable monitor (PM) or type 4 PM might be a viable alternative to PSG for the diagnosis of OSA in postpolio subjects.

Methods

A total of 48 community-living polio survivors (39 men and 9 women) with an average age of 54.4 ± 5.3 years referred for the evaluation of OSA and who volunteered to participate were recruited. First, they completed the Epworth Sleepiness Scale (ESS) questionnaire and underwent pulmonary function testing and blood gas tests the day before PSG night. Then, they underwent an overnight in-laboratory PSG with a type 3 PM and type 4 PM recording simultaneously.

Results

The AHI from PSG, respiratory event index (REI) from type 3 PM, and ODI₃ from type 4 PM was 30.27 ± 22.51/h vs. 25.18 ± 19.11/h vs. 18.28 ± 15.13/h, respectively (P < 0.001). For AHI ≥ 5/h, the sensitivity and specificity of REI were 95.45 and 50%, respectively. For AHI ≥ 15/h, the sensitivity and specificity of REI were 87.88% and 93.33%, respectively. The Bland-Altman analysis of REI on PM vs. AHI on PSG showed a mean difference of -5.09 (95% confidence interval [CI]: -7.10, -3.08; P < 0.001) with limits of agreement ranging from -18.67 to 8.49 events/h. ROC curve analysis for patients with REI ≥ 15/h showed an area under the curve (AUC) of 0.97. For AHI ≥ 5/h, the sensitivity and specificity of ODI₃ from type 4 PM were 86.36 and 75%, respectively. For patients with AHI ≥ 15/h, the sensitivity was 66.67%, and the specificity was 100%.

Conclusion

Type 3 PM and Type 4 PM could be alternative ways to screen OSA for polio survivors, especially for moderate to severe OSA.

Feasibility study of the Nox-T3 device to detect swallowing and respiration pattern in neurologically impaired patients in the acute phase

Dysphagia is a frequent complication in neurologically impaired patients, which can lead to aspiration pneumonia and thus prolonged hospitalization or even death. It is essential therefore, to detect and assess dysphagia early for best patient care. Fiberoptic endoscopic and Videofluoroscopy evaluation of swallowing are the gold standard exams in swallowing studies but neither are perfectly suitable for patients with disorders of consciousness (DOC). In this study, we aimed to find the sensitivity and specificity of the Nox-T3 sleep monitor for detection of swallowing. A combination of submental and peri-laryngeal surface electromyography, nasal cannulas and respiratory inductance plethysmography belts connected to Nox-T 3 allows recording swallowing events and their coordination with breathing, providing time-coordinated patterns of muscular and respiratory activity. We compared Nox-T3 swallowing capture to manual swallowing detection on fourteen DOC patients. The Nox-T3 method identified swallow events with a sensitivity of 95% and a specificity of 99%. In addition, Nox-T3 has qualitative contributions, such as visualization of the swallowing apnea in the respiratory cycle which provide additional information on the swallowing act that is useful to clinicians in the management and rehabilitation of the patient. These results suggest that Nox-T3 could be used for swallowing detection in DOC patients and support its continued clinical use for swallowing disorder investigation.

Diagnosing sleep disordered breathing in patients with chronic pulmonary disease: which test for which patient?

Overnight polysomnography should be the first-line diagnostic test in patients with severe respiratory disease. However, if access to polysomnography is limited, overnight polygraphy can be used as an alternative first-line diagnostic. https://bit.ly/3KlmFED.

Portable evaluation of obstructive sleep apnea in adults: A systematic review

Obstructive sleep apnea (OSA) is a significant healthcare burden affecting approximately one billion people worldwide. The prevalence of OSA is rising with the ongoing obesity epidemic, a key risk factor for its development. While in-laboratory polysomnography (PSG) is the gold standard for diagnosing OSA, it has significant drawbacks that prevent widespread use. Portable devices with different levels of monitoring are available to allow remote assessment for OSA. To better inform clinical practice and research, this comprehensive systematic review evaluated diagnostic performances, study cost and patients' experience of different levels of portable sleep studies (type 2, 3, and 4), as well as wearable devices and non-contact systems, in adults. Despite varying study designs and devices used, portable diagnostic tests are found to be sufficient for initial screening of patients at risk of OSA. Future studies are needed to evaluate cost effectiveness with the incorporation of portable diagnostic tests into the diagnostic pathway for OSA, as well as their application in patients with chronic respiratory diseases and other comorbidities that may affect test performance.

ERS technical standards for using type III devices (limited channel studies) in the diagnosis of sleep disordered breathing in adults and children

For more than three decades, type III devices have been used in the diagnosis of sleep disordered breathing in supervised as well as unsupervised settings. They have satisfactory positive and negative predictive values for detecting obstructive and central sleep apnoea in populations with moderately high pre-test probability of symptoms associated with these events. However, standardisation of commercially available type III devices has never been undertaken and the technical specifications can vary widely. None have been subjected to the same rigorous processes as most other diagnostic modalities in the medical field. Although type III devices do not include acquisition of electroencephalographic signals overnight, the minimum number of physical sensors required to allow for respiratory event scoring using standards outlined by the American Academy of Sleep Medicine remains debatable. This technical standard summarises data on type III studies published since 2007 from multiple perspectives in both adult and paediatric sleep practice. Most importantly, it aims to provide a framework for considering current type III device limitations in the diagnosis of sleep disordered breathing while raising research- and practice-related questions aimed at improving our use of these devices in the present and future.

Smart home healthcare for chronic disease management: A scoping review

Objective

Chronic disease is the leading cause of morbidity and mortality on a global scale. Recent use of intelligent home environments for remote health monitoring has allowed patients to feel safe at home. By encouraging patient engagement and, if necessary, care delivery, smart home environments may be a useful method for managing chronic diseases at home. The purpose of this study is to synthesize the evidence on the usage of smart healthcare in the home for chronic illness management.

Methods

We conducted a scoping review using the Joanna Briggs Methodology and searched three databases from 2017 to 2022 for original research papers on smart healthcare, smart home technology, home-based technology, home monitoring, and physiological monitoring for chronic illness management. We did a descriptive study on the pertinent data we collected, as well as an analysis of whether the devices met its objectives.

Results

The final analysis included nine papers, the majority of which were randomized controlled trials. All of the studies were carried out in developed countries. The gadgets or smart healthcare in these studies are categorized based on the technology used and the outcomes measured. Respiratory, weight, and ballistocardiograph measurements, as well as changes in questionnaire ratings, hospitalization, activity monitoring, device acceptability, medication adherence, exercise capacity, and body function, were all measured.

Conclusion

Smart healthcare applications boost health by monitoring health and wellness, recording physical activity and rehabilitation, and improving overall quality of life. Not all smart home applications, however, served their intended purpose. As a result, more research into the efficacy of smart healthcare is needed to improve its application for chronic illness treatment.

The Overlap Syndrome of Obstructive Sleep Apnea and Chronic Obstructive Pulmonary Disease: A Systematic Review

Chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea (OSA) are common diseases that strongly impact the quality and length of life. Their coexistence is determined by overlap syndrome (OS). This systematic review aims to define the significance of these comorbidities according to the current state of knowledge. For this systematic review, we searched PubMed, Scopus, and Cochrane for studies published between 2018 and 26 October 2022, to find original, observational, human studies published in English, where the diagnosis of COPD was according to the Global Initiative for Obstructive Lung Disease guidelines and the diagnosis of OSA was based on polysomnography. The quality of studies was assessed using the Newcastle-Ottawa quality assessment tool for cohort and case-control studies, as well as its modification for cross-sectional studies. Of the 1548 records identified, 38 were eligible and included in this systematic review. The included studies covered a total population of 27,064 participants. This paper summarizes the most important, up-to-date information regarding OS, including the prevalence, meaning of age/gender/body mass index, polysomnography findings, pulmonary function, comorbidities, predicting OSA among COPD patients, and treatment of this syndrome.

Sleep Deficiency, Sleep Apnea, and Chronic Lung Disease

With sleep occupying up to one-third of every adult's life, addressing sleep is essential to overall health. Sleep disturbance and deficiency are common in patients with chronic lung diseases and associated with worse clinical outcomes and poor quality of life. A detailed history incorporating nocturnal respiratory symptoms, symptoms of obstructive sleep apnea (OSA) and restless legs syndrome, symptoms of anxiety and depression, and medications is the first step in identifying and addressing the multiple factors often contributing to sleep deficiency in chronic lung disease. Additional research is needed to better understand the relationship between sleep deficiency and the spectrum of chronic lung diseases.

Diagnosis of Obstructive Sleep Apnea in Patients with Associated Comorbidity

Obstructive sleep apnea (OSA) is a heterogeneous disease with many physiological implications. OSA is associated with a great diversity of diseases, with which it shares common and very often bidirectional pathophysiological mechanisms, leading to significantly negative implications on morbidity and mortality. In these patients, underdiagnosis of OSA is high. Concerning cardiorespiratory comorbidities, several studies have assessed the usefulness of simplified screening tests for OSA in patients with hypertension, COPD, heart failure, atrial fibrillation, stroke, morbid obesity, and in hospitalized elders.The key question is whether there is any benefit in the screening for the existence of OSA in patients with comorbidities. In this regard, there are few studies evaluating the performance of the various diagnostic procedures in patients at high risk for OSA. The purpose of this chapter is to review the existing literature about diagnosis in those diseases with a high risk for OSA, with special reference to artificial intelligence-related methods.

Obstructive Sleep Apnea with COVID-19

The novel coronavirus disease-2019 (COVID-19) and the ensuing pandemic have greatly impacted the global healthcare system due to its high infectiousness, associated high mortality, and a complete lack of immunity in the population. Globally, the COVID-19 pandemic has unleashed a health crisis that has not only seriously disrupted people's lives but also affected their normal sleep, along with physical and mental health; this situation is especially exacerbated in people suffering from pre-existing conditions, such as sleep apnea. A recent meta-analysis of 18 studies by Miller et al. (September 2020) showed that obstructive sleep apnea (OSA) is related to higher mortality and morbidity in patients with COVID-19 and is most likely independent of other risk factors. A recent meta-analysis indicated that COVID-19 patients with OSA are more severely affected than those without OSA, thereby providing further evidence that concurrent OSA may elevate the severity of COVID-19 infection, along with the risk of mortality. The COVID-19 pandemic has significantly impacted the diagnosis and therapeutic management of patients with OSA. Thus, it is necessary to identify and develop new diagnostic and therapeutic avenues in the future. In this context, the current study summarizes known associations between COVID-19 and OSA and the regular diagnostic and therapeutic strategies for OSA in the light of COVID-19 pandemic prevention and control.

Accuracy and usability of AcuPebble SA100 for automated diagnosis of obstructive sleep apnoea in the home environment setting: an evaluation study

OBJECTIVES

Obstructive sleep apnoea (OSA) is a heavily underdiagnosed condition, which can lead to significant multimorbidity. Underdiagnosis is often secondary to limitations in existing diagnostic methods. We conducted a diagnostic accuracy and usability study, to evaluate the efficacy of a novel, low-cost, small, wearable medical device, AcuPebble_SA100, for automated diagnosis of OSA in the home environment.

SETTINGS

Patients were recruited to a standard OSA diagnostic pathway in an UK hospital. They were trained on the use of type-III-cardiorespiratory polygraphy, which they took to use at home. They were also given AcuPebble_SA100; but they were not trained on how to use it.

PARTICIPANTS

182 consecutive patients had been referred for OSA diagnosis in which 150 successfully completed the study.

PRIMARY OUTCOME MEASURES

Efficacy of AcuPebble_SA100 for automated diagnosis of moderate-severe-OSA against cardiorespiratory polygraphy (sensitivity/specificity/likelihood ratios/predictive values) and validation of usability by patients themselves in their home environment.

RESULTS

After returning the systems, two expert clinicians, blinded to AcuPebble_SA100's output, manually scored the cardiorespiratory polygraphy signals to reach a diagnosis. AcuPebble_SA100 generated automated diagnosis corresponding to four, typically followed, diagnostic criteria: Apnoea Hypopnoea Index (AHI) using 3% as criteria for oxygen desaturation; Oxygen Desaturation Index (ODI) for 3% and 4% desaturation criteria and AHI using 4% as desaturation criteria. In all cases, AcuPebble_SA100 matched the experts' diagnosis with positive and negative likelihood ratios over 10 and below 0.1, respectively. Comparing against the current American Academy of Sleep Medicine's AHI-based criteria demonstrated 95.33% accuracy (95% CI (90·62% to 98·10%)), 96.84% specificity (95% CI (91·05% to 99·34%)), 92.73% sensitivity (95% CI (82·41% to 97·98%)), 94.4% positive-predictive value (95% CI (84·78% to 98·11%)) and 95.83% negative-predictive value (95% CI (89·94% to 98·34%)). All patients used AcuPebble_SA100 correctly. Over 97% reported a strong preference for AcuPebble_SA100 over cardiorespiratory polygraphy.

CONCLUSIONS

These results validate the efficacy of AcuPebble_SA100 as an automated diagnosis alternative to cardiorespiratory polygraphy; also demonstrating that AcuPebble_SA100 can be used by patients without requiring human training/assistance. This opens the doors for more efficient patient pathways for OSA diagnosis.

TRIAL REGISTRATION NUMBER

NCT03544086; ClinicalTrials.gov.

A Minimum Set of Physiological Parameters to Diagnose Obstructive Sleep Apnea Syndrome Using Non-Invasive Portable Monitors. A Systematic Review

Introduction. Despite its high accuracy, polysomnography (PSG) has several drawbacks for diagnosing obstructive sleep apnea (OSA). Consequently, multiple portable monitors (PMs) have been proposed. Objective. This systematic review aims to investigate the current literature to analyze the sets of physiological parameters captured by a PM to select the minimum number of such physiological signals while maintaining accurate results in OSA detection. Methods. Inclusion and exclusion criteria for the selection of publications were established prior to the search. The evaluation of the publications was made based on one central question and several specific questions. Results. The abilities to detect hypopneas, sleep time, or awakenings were some of the features studied to investigate the full functionality of the PMs to select the most relevant set of physiological signals. Based on the physiological parameters collected (one to six), the PMs were classified into sets according to the level of evidence. The advantages and the disadvantages of each possible set of signals were explained by answering the research questions proposed in the methods. Conclusions. The minimum number of physiological signals detected by PMs for the detection of OSA depends mainly on the purpose and context of the sleep study. The set of three physiological signals showed the best results in the detection of OSA.

Improving Machine Learning Technology in the Field of Sleep

The authors discuss the challenges of machine- and deep learning-based automatic analysis of obstructive sleep apnea with respect to known issues with the signal interpretation, patient physiology, and the apnea-hypopnea index. Their goal is to provide guidance for sleep and machine learning professionals working in this area of sleep medicine. They suggest that machine learning approaches may well be better targeted at examining and attempting to improve the diagnostic criteria, in order to build a more nuanced understanding of the detailed circumstances surrounding OSA, rather than merely attempting to reproduce human scoring.

Using a portable monitoring device for diagnosing obstructive sleep apnea in patients with multiple coexisting medical illnesses

INTRODUCTION

The existing guidelines recommend type III devices should be used in patients without significant comorbidities.

OBJECTIVES

This study explored the reliability of using a type III device in patients with significant medical conditions to diagnose sleep apnea.

METHODS

Patients had an overnight sleep study conducted simultaneously with both polysomnography (PSG) and a type III (NOX-T3) monitoring device. All patients had stable multiple coexisting medical illnesses without any changes in medications and conditions within 1 month of sleep study.

RESULTS

Between July 2019 and March 2020, there were altogether 74 patients recruited with analyzable data. Five major disease groups were identified in the cohort: psychiatric illnesses, stroke, ischemic heart diseases (IHDs), chronic kidney diseases (CKDs), and others. Psychiatric patients with medications were found to have the lowest apnea hypopnea index (AHI) (23.7 per hour) and arousal index (46.6 per hour). The CKD group had the highest mean arousal index (71.4 per hour) and obstructive apnea count (110.2). NOX-T3 respiratory event index (REI) was significantly lower than the PSG AHI (mean REI 31.4 vs. mean AHI: 42.2). The number of patients with no/mild/moderate/severe obstructive sleep apnea (OSA) diagnosed by NOX-T3 and PSG was 7/17/19/31 and 5/11/20/38, respectively.

CONCLUSION

NOX-T3 device can reliably diagnose OSA in patients with different stable coexisting medical conditions. There is a tendency for underestimation of the severity of the OSA with NOX-T3 in patients with coexisting medical conditions especially with sedative medications. A positive NOX-T3 reliably diagnoses OSA whereas a negative NOX-T3 result needs to be interpreted with caution.

Obstructive Sleep Apnea in Patients with Chronic Obstructive Pulmonary Disease: Facts and Perspectives

The co-occurrence of obstructive sleep apnea (OSA) and chronic obstructive pulmonary disease (COPD) in the same patient, named the overlap syndrome (OS), was first described in 1985. Although the American Thoracic Society underlined the limited knowledge of OS, stated research priorities for this condition, and recommended a "screening" strategy to identify OSA in COPD patients with chronic stable hypercapnia, research studies on OS remain scarce. This review aims to summarize the current knowledge and perspectives related to OSA in COPD patients. OS prevalence is 1.0-3.6% in the general population, 3-66% in COPD patients, and 7-55% in OSA patients. OS patients may have worse sleep quality than those with OSA or COPD alone. Scoring hypopneas may be difficult in COPD patients; desaturation episodes may have origins in these patients, namely upper airway obstruction, hypoventilation during paradoxical sleep, ventilation/perfusion mismatches, and obesity. The apnea-hypopnea index is similar in OSA and OS patients. Desaturations may be greater and more prolonged in OS patients than in patients with COPD or OSA alone. Low body mass index, hyperinflation, and less collapsible airways reduce the risk of OSA in COPD patients. OSA is a risk factor for pulmonary hypertension in COPD patients. Whether OS increases mortality and morbidity risks compared to COPD or OSA alone remains to be confirmed. No guidelines currently recommend specific approaches to the treatment of OSA in patients with COPD.

A review of therapies for the overlap syndrome of obstructive sleep apnea and chronic obstructive pulmonary disease

Obstructive sleep apnea (OSA) and chronic obstructive pulmonary disease (COPD) are common chronic diseases. These two noncommunicable diseases (NCDs) are prevalent among approximately 10% of the general population. Approximately 1% of the population is affected by the co-existence of both conditions, known as the overlap syndrome (OS). OS patients suffer from greater degrees of nocturnal oxygen desaturation and cardiovascular consequences than those with either condition in isolation. Besides OS, patients with COPD may suffer from a spectrum of sleep-related breathing disorders, including hypoventilation and central sleep apnea. The article provides an overview of the pathogenesis, associated risk factors, prevalence, and management of sleep-related breathing disorders in COPD. It examines respiratory changes during sleep caused by COPD and OSA. It elaborates upon the factors that link the two conditions together to lead to OS. It also discusses the clinical evaluation and diagnosis of these patients. Subsequently, it reviews the pathophysiological basis and the current evidence for three potential therapies: positive airway pressure therapy [including continuous positive airway pressure (CPAP) and bilevel positive airway pressure], oxygen therapy, and pharmacological therapy. It also proposes a phenotypic approach toward the diagnosis and treatment of OS and the entire spectrum of sleep-related breathing disorders in COPD. It concludes with the current evidence gaps and future areas of research in the management of OS.

Home sleep apnea testing of adults with chronic heart failure

STUDY OBJECTIVES

To evaluate home sleep apnea testing (HSAT) using a type 3 portable monitor to help diagnose sleep-disordered breathing (SDB) and identify respiratory events including obstructive sleep apnea, central sleep apnea, and Cheyne-Stokes respiration in adults with stable chronic heart failure.

METHODS

Eighty-four adults with chronic heart failure (86.9% males, age [mean ± standard deviation] 58.7 ± 16.3 years, body mass index 29.4 ± 13.0 kg/m², left ventricular ejection fraction 40.3% ± 11.5%) performed unattended HSAT followed by an in-laboratory polysomnography (PSG) with simultaneous portable monitor recording.

RESULTS

The apnea-hypopnea index was 22.0 ± 17.0 events/h according to HSAT, 26.8 ± 20.5 events/h on an in-laboratory portable monitor, and 23.8 ± 21.3 events/h using PSG (P = .373). A Bland-Altman analysis of the apnea-hypopnea index using HSAT vs PSG showed a mean difference (95% confidence interval) of -2.4 (-4.9 to 0.1) events/h and limits of agreement (±2 standard deviations) of -24.1 to 19.2 events/h. HSAT underestimated the apnea-hypopnea index to a greater extent at a higher apnea-hypopnea index (rho = -.358; P < .001). Similar levels of agreement from HSAT vs PSG were observed when comparing the obstructive apnea index, central apnea index, and percentage of time in a Cheyne-Stokes respiration pattern. When we used an apnea-hypopnea index ≥ 5 events/h to diagnose SDB, HSAT had 86.7% sensitivity, 76.5% specificity, 92.9% positive predictive value, and 61.9% negative predictive value compared to PSG. Detection of Cheyne-Stokes respiration using HSAT showed 94.6% sensitivity, 91.1% specificity, 88.6% positive predictive value, and 97.6% negative predictive value compared to PSG.

CONCLUSIONS

HSAT with a type 3 portable monitor can help diagnose SDB and identify obstructive sleep apnea, central sleep apnea, and Cheyne-Stokes respiration events in adults with chronic heart failure.

Metrics of sleep apnea severity: beyond the apnea-hypopnea index

Obstructive sleep apnea (OSA) is thought to affect almost 1 billion people worldwide. OSA has well established cardiovascular and neurocognitive sequelae, although the optimal metric to assess its severity and/or potential response to therapy remains unclear. The apnea-hypopnea index (AHI) is well established; thus, we review its history and predictive value in various different clinical contexts. Although the AHI is often criticized for its limitations, it remains the best studied metric of OSA severity, albeit imperfect. We further review the potential value of alternative metrics including hypoxic burden, arousal intensity, odds ratio product, and cardiopulmonary coupling. We conclude with possible future directions to capture clinically meaningful OSA endophenotypes including the use of genetics, blood biomarkers, machine/deep learning and wearable technologies. Further research in OSA should be directed towards providing diagnostic and prognostic information to make the OSA diagnosis more accessible and to improving prognostic information regarding OSA consequences, in order to guide patient care and to help in the design of future clinical trials.

Evaluation and Management of Adults with Obstructive Sleep Apnea Syndrome

Obstructive sleep apnea syndrome (OSAS) is a common and underdiagnosed medical condition characterized by recurrent sleep-dependent pauses and reductions in airflow. While a narrow, collapsible oropharynx plays a central role in the pathophysiology of OSAS, there are other equally important nonanatomic factors including sleep-stage dependent muscle tone, arousal threshold, and loop gain that drive obstructive apneas and hypopneas. Through mechanisms of intermittent hypoxemia, arousal-related sleep fragmentation, and intrathoracic pressure changes, OSAS impacts multiple organ systems. Risk factors for OSAS include obesity, male sex, age, specific craniofacial features, and ethnicity. The prevalence of OSAS is rising due to increasing obesity rates and improved sensitivity in the tools used for diagnosis. Validated questionnaires have an important but limited role in the identification of patients that would benefit from formal testing for OSA. While an in-laboratory polysomnography remains the gold standard for diagnosis, the widespread availability and accuracy of home sleep apnea testing modalities increase access and ease of OSAS diagnosis for many patients. In adults, the most common treatment involves the application of positive airway pressure (PAP), but compliance continues to be a challenge. Alternative treatments including mandibular advancement device, hypoglossal nerve stimulator, positional therapies, and surgical options coupled with weight loss and exercise offer possibilities of an individualized personal approach to OSAS. Treatment of symptomatic patients with OSAS has been found to be beneficial with regard to sleep-related quality of life, sleepiness, and motor vehicle accidents. The benefit of treating asymptomatic OSA patients, particularly with regard to cardiovascular outcomes, is controversial and more data are needed.

Sleep Disordered Breathing Diagnosis and Treatment During the COVID-19 Pandemic: A Nationwide Survey in China

BACKGROUND AND OBJECTIVE

The coronavirus disease 2019 (COVID-19) pandemic has markedly impacted the distribution of medical resources and healthcare delivery systems. The objective of this study was to investigate the influence of the pandemic on the diagnosis and treatment of sleep-disordered breathing (SDB) in China.

METHODS

A retrospective online survey of sleep centers from the assembly of SDB of the Chinese Thoracic Society was conducted from July 1 to July 20, 2020. The questionnaire focused on four main aspects: 1) general information about the centers; 2) changes in SDB management activities, including patient volumes, diagnostic and positive airway pressure (PAP) titration procedures, and follow-up methods, from February to June 2020, compared with before; 3) the application of telemedicine and sleep specialists' self-assessments of knowledge and their perspectives on telemedicine; and 4) changes in medical staff active in sleep services during the pandemic compared with before.

RESULTS

Fifty-three (96%) of the sleep centers responded to the survey. During the early stage of the outbreak, SDB medical services were dramatically reduced to 5-10% of the pre-epidemic level, and laboratory-based polysomnograms and manual titration were almost cancelled. With the subsidence of COVID-19, SDB medical services gradually resumed to approximately half of the pre-pandemic level by June. However, a second wave of COVID-19 in Beijing significantly reduced the recovery of SDB services. The application of polygraphy has increased significantly. Home-initiated PAP and telemedicine still accounted for a small part of SDB management during the pandemic.

CONCLUSION

The COVID-19 pandemic has greatly challenged SDB management in China. Polygraphy played a major role in SDB diagnosis during the pandemic. Home-based SDB management and telemedicine have not been well implemented. The second surge of COVID-19 in Beijing cut back on the recovering SDB service to the early outbreak level, which may give us an impetus to restructure our sleep health service.

Alternative Care Pathways for Obstructive Sleep Apnea and the Impact on Positive Airway Pressure Adherence: Unraveling the Puzzle of Adherence

The high burden of obstructive sleep apnea (OSA), combined with inadequate supply of sleep specialists and constraints on polysomnography resources, has prompted interest in alternative models of care to improve access and treatment effectiveness. In appropriately selected patients, ambulatory clinical pathways and use of nonphysicians or primary care providers to manage OSA can improve timely access and costs without compromising adherence or other clinical outcomes. Although initial studies show promising results, there are several potential barriers that must be considered before broad implementation, and further implementation research and economic evaluation studies are required.

Prevalence and management of sleep disorders in the Veterans Health Administration

The prevalence of diagnosed sleep disorders among Veterans treated at Veterans Affairs (VA) medical facilities increased significantly during fiscal years (FY) 2012 through 2018. Specifically, the prevalence of sleep-related breathing disorders (SRBD) increased from 5.5% in FY2012 to 22.2% in FY2018, and the prevalence of insomnia diagnoses increased from 7.4% in FY2012 to 11.8% in FY2018. Consequently, Veterans' demand for sleep medicine services also increased significantly between FY2012-2018, with steady increases in the annual number of VA sleep clinic appointments during this period (<250,000 in FY 2012; >720,000 in FY2018). Common co-morbid conditions among Veterans diagnosed with sleep disorders include obesity, diabetes, congestive heart failure, depression, post-traumatic stress disorder (PTSD) and traumatic brain injury (TBI). To address this healthcare crisis, the Veterans Health Administration (VHA) developed and/or implemented numerous innovations to improve the quality and accessibility of sleep care services for Veterans. These innovations include a TeleSleep Enterprise-Wide Initiative to improve rural Veterans' access to sleep care; telehealth applications such as the Remote Veteran Apnea Management Platform (REVAMP), Clinical Video Telehealth, and CBT-i Coach; increased use of home sleep apnea testing (HSAT); and programs for Veterans who experience sleep disorders associated with obesity, PTSD, TBI and other conditions.

Diagnosis and Management of Obstructive Sleep Apnea: A Review

IMPORTANCE

Obstructive sleep apnea (OSA) affects 17% of women and 34% of men in the US and has a similar prevalence in other countries. This review provides an update on the diagnosis and treatment of OSA.

OBSERVATIONS

The most common presenting symptom of OSA is excessive sleepiness, although this symptom is reported by as few as 15% to 50% of people with OSA in the general population. OSA is associated with a 2- to 3-fold increased risk of cardiovascular and metabolic disease. In many patients, OSA can be diagnosed with home sleep apnea testing, which has a sensitivity of approximately 80%. Effective treatments include weight loss and exercise, positive airway pressure, oral appliances that hold the jaw forward during sleep, and surgical modification of the pharyngeal soft tissues or facial skeleton to enlarge the upper airway. Hypoglossal nerve stimulation is effective in select patients with a body mass index less than 32. There are currently no effective pharmacological therapies. Treatment with positive airway pressure lowers blood pressure, especially in patients with resistant hypertension; however, randomized clinical trials of OSA treatment have not demonstrated significant benefit on rates of cardiovascular or cerebrovascular events.

CONCLUSIONS AND RELEVANCE

OSA is common and the prevalence is increasing with the increased prevalence of obesity. Daytime sleepiness is among the most common symptoms, but many patients with OSA are asymptomatic. Patients with OSA who are asymptomatic, or whose symptoms are minimally bothersome and pose no apparent risk to driving safety, can be treated with behavioral measures, such as weight loss and exercise. Interventions such as positive airway pressure are recommended for those with excessive sleepiness and resistant hypertension. Managing asymptomatic OSA to reduce cardiovascular and cerebrovascular events is not currently supported by high-quality evidence.

Multimorbidity in COPD, does sleep matter?

A good night's sleep is a prerequisite for sustainable mental and physical health. Sleep disorders, including sleep disordered breathing, insomnia and sleep related motor dysfunction (e.g., restless legs syndrome), are common in patients with chronic obstructive pulmonary disease (COPD), especially in more severe disease. COPD is commonly associated with multimorbidity, and sleep disorders as a component of this multimorbidity spectrum have a further negative impact on COPD-related comorbidities. Indeed, concomitant diseases in COPD and in obstructive sleep apnea (OSA) are similar, suggesting that the combination of COPD and OSA, the so called OSA-COPD overlap syndrome (OVS), affects patient outcomes. Potential clinically important interactions of OVS exist in cardiovascular and metabolic disease, arthritis, anxiety, depression, neurocognitive disorder and the fatigue syndrome. Correct diagnosis for recognition and treatment of sleep-related disorders in COPD is recommended. However, surprisingly limited information is available and further research and improved diagnostic tools are needed. In the absence of clear evidence, we agree with the recommendation of the Global Initiative on Chronic Obstructive Lung Disease that sleep disorders should be actively searched for and treated in patients with COPD. We believe that both aspects are important components of the holistic approach required in patients with chronic multimorbid conditions.

Reliability of Home Nocturnal Oximetry in the Diagnosis of Overlap Syndrome in COPD

BACKGROUND

Chronic obstructive pulmonary disease (COPD) and sleep apnea are common conditions and often coexist. The proper diagnosis of sleep apnea may affect the management and outcome of patients with COPD.

OBJECTIVE

To determine the accuracy of home nocturnal oximetry to distinguish between nocturnal oxygen desaturation related to COPD alone or to sleep apnea in patients with moderate-to-severe COPD who have significant nocturnal hypoxemia with cyclical changes in saturation.

METHODS

This study involved a comparison of home nocturnal oximetry and laboratory-based polysomnography (PSG) in patients with moderate-to-severe COPD considered for inclusion in a trial of nocturnal oxygen therapy. All of the patients had significant nocturnal oxygen desaturation (defined as ≥30% of the recording time with a transcutaneous arterial oxygen saturation <90%) with cyclical changes in saturation suggestive of sleep apnea.

RESULTS

PSG was obtained in 90 patients; 45 patients (mean age = 68 years, SD = 8; 71% men; mean forced expiratory volume in 1 s [FEV1] = 50.6% predicted value, SD = 18.6%; data from 41 patients) fulfilled the criteria for sleep apnea (mean apnea-hypopnea index = 32.6 events/h, SD = 19.9) and 45 patients (mean age = 69 years, SD = 8; 87% men; mean FEV1 predicted value 44.6%, SD = 15%) did not (mean apnea-hypopnea index = 5.5 events/h, SD = 3.8). None of the patients' characteristics (including demographic, anthropometric, and physiologic measures) predicted the diagnosis of sleep apnea according to PSG results.

CONCLUSION

The diagnosis of sleep apnea in patients with moderate to severe COPD cannot rely on nocturnal oximetry alone, even when typical cyclical changes in saturation are seen on oximetry tracing. When suspecting an overlap syndrome, a full-night, in-laboratory PSG should be obtained.