Evaluation of a multicomponent grading system for obstructive sleep apnoea: the Baveno classification

Estimating the costs and analysing the precision of several diagnostic and treatment approaches for obstructive sleep apnea patients in the Netherlands, using timed automata modelling

Obstructive Sleep Apnea (OSA) is a (highly) prevalent medical condition, linked to severe negative health consequences. In the Netherlands, diagnosis of OSA presently has long waiting times and both diagnosis and treatment have high costs. This article introduces a so-called timed automata model (UPPAAL tool) for analysing diagnostic and treatment approaches for OSA. This model is used for assessing the Dutch current traditional approach, as well as multiple alternative approaches for OSA diagnosis and treatment. The analysis shows that one alternative approach can lower the costs and waiting lists, while maintaining diagnostic precision. In this manuscript the best alternative approach is a combination of Oxygen Desaturation Index (ODI) measurement obtained by nocturnal pulse oximetry and a questionnaire to diagnose the patient. Of course, it is important that, although timed automata modelling is a reliable tool, these outcomes are meant to start a discussion regarding the above-mentioned problems and are not proven outcomes yet. The healthcare system in the Netherlands is in danger of becoming unaffordable. Therefore, this initial exploration has been carried out to see whether alternatives to the current OSA-care can be devised.

Overlap Syndrome (COPD and OSA): A Treatable Trait for Triple Treatment?

The coexistence of chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea (OSA) in the same patient is referred to as overlap syndrome (OS). Patients with OS suffer more frequently from cardiovascular disease (CVD) and carry a higher risk of COPD-related exacerbations than patients with COPD alone, especially when OSA is left untreated. Based on recent evidence, triple therapy, namely inhaled corticosteroid/long-acting muscarinic antagonist/long-acting beta-agonist (ICS-LABA-LAMA), is a treatment strategy in COPD patients with a history of exacerbations and/or CVD comorbidity. While several studies have previously focused on the role of triple therapy in patients with COPD, none of these has examined the potential benefits of this treatment in patients with COPD and concomitant OSA. Moreover, it is unknown whether patients with OS should be treated with triple therapy starting from their initial assessment, since they represent a population at risk for future exacerbations, in comparison to patients with COPD alone. In this commentary, we discuss these issues and highlight the need for further studies regarding the role of triple therapy in outcomes for patients with OS.

The Past and Future of Sleep Medicine

The past of sleep medicine is rich with seminal discoveries, from the recognition of clinical syndromes to measurement of sleep itself to classic and novel therapeutics. Advances in neurobiology have mapped a number of sleep circuits, described the central and peripheral circadian system, and identified the cause of narcolepsy with cataplexy. Sleep apnea endotypes and phenotypes now have established clinical relevance, though treatment implications are a work in progress. Artificial intelligence will continue to change sleep medicine in a number of domains from aiding scoring to health outcome predictions. There is a large gap between the known science and clinical translational.

Prevalence and association analysis of obstructive sleep apnea in India: Results from BLESS cohort

BACKGROUND

Despite having the largest population in the world with 1.4 billion inhabitants, there is only scarce data on the prevalence of OSA from India.

RESEARCH QUESTION

This study aimed to find the prevalence of Obstructive Sleep Apnea (OSA) using Polysomnography (PSG) and current scoring rules (AASM 2012) in population and investigate OSA associations for cardiovascular and metabolic comorbidities.

STUDY DESIGN

and Methods: Participants were randomly selected among the accompanying attendants of patients admitted to a hospital in Bhopal, India and underwent level I PSG. Anthropometric measurements, blood investigations were taken. The primary outcome was prevalence of OSA, assessed by the Apnoea-Hypopnoea Index (AHI).

RESULTS

Level I PSG was performed on 1015 adult participants from December 2019 to February 2023; after excluding 57 participants with sleep time <240 min, 958 participants (age range 18-80 years) were finally included in this study. Median (IQR) age was 40.0 years (31.0, 49.0) while median (IQR) BMI was 23.5 (20.7, 26.8) Kg/m2. Prevalence (95 % CI) of moderate-to-severe OSA (AHI ≥15) and severe OSA (AHI≥30) was 30.5 % (28-34 %) and 10.1 % (8.3-12), respectively. The upper quartile of the AHI (Q4 ≥17) was independently associated with the presence of Diabetes Mellitus [OR 2.14 (95 % CI 1.07-4.44)], Hypertension [OR1.98 (95 % CI 1.20-3.28)] and Metabolic Syndrome [OR 2.36 (95 % CI 1.37-4.09)] compared to the first quartile AHI.

INTERPRETATION

OSA prevalence was found to be significantly higher than previously estimated in Indian population. Association of OSA with diabetes, hypertension, and metabolic syndrome was observed.

New management pathways for follow-up of CPAP-treated sleep apnoea patients including digital medicine and multimodal telemonitoring

BACKGROUND

The ever-increasing number of patients diagnosed with obstructive sleep apnoea (OSA) and treated by long-term continuous positive airway pressure (CPAP) overstretches conventional follow-up pathways. New approaches to the management of CPAP-treated patient follow-up are needed to strike a balance between remote monitoring through digital technologies and in-person patient-healthcare-professional contacts. Focusing on the reshaping of the management of care pathways of CPAP-treated patients, with a specific focus on telemonitoring platforms, we aimed to review the evidence on how digital medicine and artificial intelligence (AI) tools are facilitating patient phenotyping and triage, risk stratification and the allocation of resources between the various healthcare professionals for an optimal follow-up of CPAP-treated patients.

PHENOTYPING

OSA is a heterogeneous condition with diverse phenotypes differing in symptoms, comorbidities, demographics, lifestyle and socioeconomic context. Different phenotypes are associated with different CPAP adherence patterns and differing long-term prognosis. This diversity demands greater plurality in management pathways with different types and levels of support to ensure treatment adherence and risk reduction for patients while easing the burden on health services. In multidimensional phenotyping, we discuss alternatives to the apnoea hypopnoea index (AHI) as a measure of OSA severity. Then we consider risk stratification taking advantage of the wealth of CPAP monitoring data already available in databases that can now be exploited using AI and machine learning to direct (stratify) patients into appropriate follow-up management pathways.

INTEGRATED CARE CLINICS FOR HIGH-RISK PATIENTS

We look at the role of integrated OSA care clinics particularly for the management of high-risk patients with low adherence and progression of comorbidities. Here, multidisciplinary teams might propose comorbidity management, and the use of connected wearable devices for long-term monitoring of physical activity, along with remote CPAP monitoring.

REMOTE MANAGEMENT PATHWAYS

The pros and cons of remote management pathways to replace in-person follow-up visits are considered, including the need to re-evaluate CPAP-device reimbursement policies in some countries. While remote CPAP monitoring has become the cornerstone of follow-up providing information on adherence and efficacy, the processing of alerts needs to be improved, particularly regarding mask changes and early detection of CPAP failures.

CHALLENGES

The implementation of CPAP monitoring alone, as well as its extension to multimodal monitoring, can present challenges that remain to be addressed (eg, access to digital care). The extent and components of remote follow-up must be adapted to each specific OSA phenotype. Finally, we give examples of certain patient phenotypes (eg, comorbid insomnia with OSA) with specific follow-up requirements, for which remote (even multimodal) monitoring alone has limitations and the intervention of both sleep specialists and/or their colleagues from other disciplines is needed.

CONCLUSION

Appropriately tailored combined digital and in-person CPAP follow-up pathways would present advantages both for patients with OSA and healthcare services.

Exploring the complexity of obstructive sleep apnea: findings from machine learning on diagnosis and predictive capacity of individual factors

PURPOSE

Obstructive sleep apnoea (OSA) is a prevalent sleep disorder characterized by pharyngeal airway collapse during sleep, leading to intermittent hypoxia, intrathoracic pressure swings, and sleep fragmentation. OSA is associated with various comorbidities and risk factors, contributing to its substantial economic and social burden. Machine learning (ML) techniques offer promise in predicting OSA severity and understanding its complex pathogenesis. This study aims to compare the accuracy of different ML techniques in predicting OSA severity and identify key associated factors contributing to OSA.

METHODS

Adult patients suspected of OSA underwent clinical assessments and polysomnography. Demographic, anthropometric and clinical data were collected. Five supervised ML models (logistic regression, decision tree, random forest, extreme gradient boosting, support vector machine) were employed, optimized through grid search and cross-validation.

RESULTS

ML models exhibited varied performance across OSA severity levels. SVM demonstrated the highest accuracy for mild OSA, XGBoost for moderate OSA, and random forest for severe OSA. Logistic regression showed the highest AUC for moderate and severe OSA. Anthropometric measures, gender, and hypertension were significant predictors of OSA severity.

CONCLUSION

ML models offer valuable insights into predicting OSA severity and identifying associated factors. Our findings support the relevant potential clinical utility of ML in OSA management, although further validation and refinement are warranted.

The relationship between composite lipid indices and baveno classification in patients with obstructive sleep apnoea

Obstructive Sleep Apnoea (OSA) is associated with the development of cardiovascular disease (CVD); however, the risk is only weekly related to OSA severity traditionally determined by the apnoea-hypopnoea index. The Baveno classification was developed to improve patient selection who would benefit from OSA treatment in terms of symptoms improvement and CVD risk reduction. However, it is unclear how the classification relates to biomarkers of CVD risk. Composite lipid indices were evaluated in various populations and showed good predictive value for incident CVD. One thousand two hundred and forty-two patients with OSA were included in the study. Composite lipid indices, including the atherogenic index of plasma (AIP), visceral adiposity index (VAI), lipid accumulation product (LAP) and cardiometabolic index (CMI) were compared between different Baveno groups (A - minor symptoms, minor comorbidities, B - severe symptoms, minor comorbidities, C - minor symptoms, severe comorbidities, D - severe symptoms, severe comorbidities). All composite lipid indices were higher in group D versus groups A and C. Only LAP (86.93 /58.40-119.49/ vs. 75.73 /48.37-99.04/) and CMI (1.03 /0.69-1.42/ vs. 0.91 /0.63-1.12/) were significantly different between the minimally symptomatic groups (C vs. A), and solely LAP was significantly higher (110.69 /76.76-147.22/ vs. 82.32 /60.35-113.50/) when the highly symptomatic groups (D vs. B) were compared. The Baveno classification correlates with cardiovascular risk estimated with composite lipid indices. Composite lipid indices may help better stratifying cardiovascular risk in both minimally- and highly symptomatic patients.

The modified Baveno classification for obstructive sleep apnoea: development and evaluation based on the ESADA database

BACKGROUND

The "Baveno classification" replaced the apnoea-hypopnoea index (AHI) with symptoms and comorbidities for treatment indication in obstructive sleep apnoea (OSA). This study evaluates a modified Baveno classification which adds a validated cardiovascular disease (CVD) risk score and acknowledges severe breathing disturbances.

METHOD

OSA patients from the European Sleep Apnoea Database (ESADA) were retrospectively allocated into CVD risk groups 1-3 based on the SCORE2 risk prediction model and European Society of Cardiology guidelines. AHI ≥30 events·h-1 conferred strong treatment indication. When AHI was <30 events·h-1, symptoms and CVD risk dictated allocation to the weak, intermediate or strong treatment indication group. Changes in Epworth Sleepiness Scale (ESS) score and office systolic blood pressure (SBP) at follow-up (12-24 months) under positive airway pressure (PAP) were assessed.

RESULTS

8625 patients were analysed (29% female; median (interquartile range) age 56 (49-64) years and body mass index 31.9 (28.4-36.3) kg·m-2). Treatment indication was weak in 501 (6%), intermediate in 2085 (24%) and strong in 6039 (70%). There was a continuous increase in age, SBP, C-reactive protein and glycosylated haemoglobin from weak to strong (p<0.001). PAP prescription increased from 52% to 64% to 93% (weak to strong; p<0.001). The change in ESS score was -2, -4 and -5, respectively (p<0.001). Reductions of ≥3 mmHg median SBP occurred when AHI was ≥30 events·h-1 and in symptomatic patients with CVD risk levels >1 when AHI was <30 events·h-1.

CONCLUSION

This analysis provides supporting evidence for the key role of CVD risk assessment and severe breathing disturbances in the identification of OSA patients most likely to benefit from treatment.

Prospective Validation and Usability Evaluation of a Mobile Diagnostic App for Obstructive Sleep Apnea

Background/Objectives: Obstructive sleep apnea (OSA) classification relies on polysomnography (PSG) results. Current guidelines recommend the development of clinical prediction algorithms in screening prior to PSG. A recent intuitive and user-friendly tool (OSABayes), based on a Bayesian network model using six clinical variables, has been proposed to quantify the probability of OSA. Our aims are (1) to validate OSABayes prospectively, (2) to build a smartphone app based on the proposed model, and (3) to evaluate app usability. Methods: We prospectively included adult patients suspected of OSA, without suspicion of other sleep disorders, who underwent level I or III diagnostic PSG. Apnea-hypopnea index (AHI) and OSABayes probabilities were obtained and compared using the area under the ROC curve (AUC [95%CI]) for OSA diagnosis (AHI ≥ 5/h) and higher severity levels (AHI ≥ 15/h) prediction. We built the OSABayes app on 'App Inventor 2', and the usability was assessed with a cognitive walkthrough method and a general evaluation. Results: 216 subjects were included in the validation cohort, performing PSG levels I (34%) and III (66%). OSABayes presented an AUC of 83.6% [77.3-90.0%] for OSA diagnosis and 76.3% [69.9-82.7%] for moderate/severe OSA prediction, showing good response for both types of PSG. The OSABayes smartphone application allows one to calculate the probability of having OSA and consult information about OSA and the tool. In the usability evaluation, 96% of the proposed tasks were carried out. Conclusions: These results show the good discrimination power of OSABayes and validate its applicability in identifying patients with a high pre-test probability of OSA. The tool is available as an online form and as a smartphone app, allowing a quick and accessible calculation of OSA probability.

[Sleep and sleep disorders in old age]

The increasing interruptions of nocturnal sleep with aging must be distinguished from actual sleep disorders. Morbidity and medication have an impact on sleep. The relationship between sleep and morbidity is mutual. Disturbed sleep modifies many clinical symptoms and diseases affect sleep and the ability to sleep. Geriatric syndromes such as falls, depression and dementia are modified by sleep disorders. Geriatric syndromes can be favorably influenced by the treatment of sleep disorders. Adequate diagnostics are important prerequisites. Coincidences of different sleep disorders are frequent. The medical history of patients and a sleep diary form the basis of the diagnostics. Sleep medicine provides further technical examination procedures. Older people should be examined in a sleep laboratory if the results have consequences that are accepted by the patient. This should be clarified in advance.

Phenotypes of obstructive sleep apnea in women: A real-life cohort study

OBJECTIVE

Obstructive sleep apnea (OSA) is a complex, heterogeneous disease. Categorizing the disorder into phenotypes can help us better understand its pathology and guide us toward more personalized treatment approaches. Nevertheless, most of the previous cluster analysis (CA) studies in OSA predominantly included middle-aged to older men and may not adequately represent the heterogeneity of OSA phenotypes in women. Our aim is to identify these phenotypes in women using an extensive, exclusively female cohort.

METHODS

Cross-sectional study of 1886 women diagnosed with OSA (apnea-hypopnea index >5 events/h) by PSG (polysomnography) and RP (respiratory polygraphy) at a tertiary hospital Sleep Unit. A CA was performed including general data, clinical variables, comorbidities and sleep study results.

RESULTS

Four phenotypic subtypes were identified: Cluster 1 "Middle-aged paucisymptomatic women without cardiovascular risk factors" (507 patients, 27 %); Cluster 2 "Older paucisymptomatic women with established cardiovascular disease and severe OSA" (228 patients, 12 %); Cluster 3 "Middle-aged women with "classic" symptoms and cardiovascular risk factors" (892 patients, 47 %), and Cluster 4 ″Middle-aged women with mood disorders, nonrestorative sleep and cardiovascular risk factors" (259 patients, 14 %).

CONCLUSIONS

Conducting a CA exclusively within a female cohort reveals a heterogeneous presentation of OSA in women, similar to what has been previously reported in the literature for men. The "classical" presentation is notably the most prevalent, while the "atypical" presentation, which was previously more frequently associated with women, is less prevalent. Additionally, paucisymptomatic presentations, with or without associated comorbidities, are also present.

A new perspective on OSAS cases with the Baveno classification

OBJECTIVE/BACKGROUND

Since the apnea-hypopnea index (AHI), which is used in the diagnosis and grading of OSAS, does not adequately reflect the clinical perspective of the disease, the Baveno classification of OSA was developed, which allows multicomponent evaluation of OSAS patients. The aim of our study was to evaluate the application of the Baveno classification in clinical practice.

PATIENTS/METHODS

A prospective study was performed on patients diagnosed with OSAS between January 2021 and June 2022. Patients were divided into 4 groups according to Baveno classification (Groups A-D) and three groups as mild, moderate, and severe OSAS according to AHI.

RESULTS

A total of 378 patients (70% male, mean age 48.68 ± 11.81 years) were included in the study. The patients had mild (n: 75; 20%), moderate (n: 88; 23%), and severe (n: 215; 57%) OSAS. According to Baveno classification, patients were included in Groups A (n: 90; 24%), B (n: 105 (28%), C (n: 65; 17%), and D (n: 118; 31%). The mean AHIs of the Baveno groups were similar (p = 0.116). Oxygen desaturation index (ODI) was higher in Groups B and D compared to Group A. The duration of T90 desaturation was longer in Groups C and D compared to Groups A and B (p < 0.05).

CONCLUSIONS

The Baveno classification divided our OSAS cases into equivalent groups. One out of every four patients with mild OSAS was in Group D. This data was noteworthy in that the Baveno classification allows for the identification of symptomatic and comorbid patients with mild OSAS according to AHI and for the application of more effective treatments to these patients. Patients with comorbidities experienced oxygen desaturation for a longer period of time at night, and oxygenation deteriorated in patients with prominent symptoms. Baveno classification was found to be a more reasonable and easily applicable approach in clinical practice.

Changes in human sweat metabolome conditioned by severity of obstructive sleep apnea and intermittent hypoxemia

Obstructive sleep apnea (OSA) is a sleep disorder that has been associated with the incidence of other pathologies. Diagnosis is mainly based on the apnea-hypopnea index (AHI) obviating other repercussions such as intermittent hypoxemia, which has been found to be associated to cardiovascular complications. Blood-based samples and urine have been the most utilised biofluids in metabolomics studies related to OSA, while sweat could be an alternative due to its non-invasive and accessible sampling, its reduced complexity, and comparability with other biofluids. Therefore, this research aimed to evaluate metabolic overnight changes in sweat collected from patients with OSA classified according to the AHI and oxygen desaturation index (ODI), looking for potential cardiovascular repercussions. Pre- and post-sleeping sweat samples from all individuals (n = 61) were analysed by gas chromatography coupled to high-resolution mass spectrometry after appropriate sample preparation to detect as many metabolites as possible. Permanent significant alterations in the sweat were reported for pyruvate, serine, lactose, and hydroxybutyrate. The most relevant overnight metabolic alterations in sweat were reported for lactose, succinate, urea, and oxoproline, which presented significantly different effects on factors such as the AHI and ODI for OSA severity classification. Overall metabolic alterations mainly affected energy production-related processes, nitrogen metabolism, and oxidative stress. In conclusion, this research demonstrated the applicability of sweat for evaluation of OSA diagnosis and severity supported by the detected metabolic changes during sleep.

Symptom content analysis of OSA questionnaires: time to identify and improve relevance of diversity of OSA symptoms?

STUDY OBJECTIVES

Obstructive sleep apnea (OSA) is a heterogeneous condition covering many clinical phenotypes in terms of the diversity of symptoms. Patient-based OSA screening questionnaires used in routine practice contain significantly varying contents that can impact the reliability and validity of the screening. We investigated to what extent common patient-based OSA screening questionnaires differ or overlap in their item content by conducting a rigorous, methodical, and quantified content overlap analysis.

METHODS

We conducted an item content analysis of 11 OSA screening questionnaires validated in adult populations and characterized their overlap using a 4-step approach: (1) selection of OSA screening questionnaires, (2) item extraction and selection, (3) extraction of symptoms from items, and (4) assessment of content overlap with the Jaccard index (from 0, no overlap, to 1, full overlap).

RESULTS

We extracted 72 items that provided 25 distinct symptoms from 11 selected OSA questionnaires. The overlap between them was weak (mean Jaccard index: 0.224; ranging from 0.138 to 0.329). All questionnaires contained symptoms of the "OSA symptom" dimension (eg, snoring or witnessed apneas). The STOP-BANG (0.329) and the Berlin (0.280) questionnaires exhibited the highest overlap content. Ten symptoms (40%) were investigated in only 1 questionnaire.

CONCLUSIONS

The heterogeneity of content and the low overlap across these questionnaires reflect the challenges of screening OSA. The different OSA questionnaires potentially capture varying aspects of the disorder, with the risk of biased results in studies. Suggestions are made for better OSA screening and refinement of clinical OSA phenotypes.

CITATION

Gauld C, Baillieul S, Martin VP, et al. Symptom content analysis of OSA questionnaires: time to identify and improve relevance of diversity of OSA symptoms? J Clin Sleep Med. 2024;20(7):1105-1117.

The PAP-RES algorithm: Defining who, why and how to use positive airway pressure therapy for OSA

Obstructive sleep apnea (OSA) is a common condition that is increasing in prevalence worldwide. Untreated OSA has a negative impact on health-related quality of life and is an independent risk factor for cardiovascular diseases. Despite available data suggesting that cardiovascular risk might differ according to clinical phenotypes and comorbidities, current approaches to OSA treatment usually take a "one size fits all" approach. Identification of cardiovascular vulnerability biomarkers and clinical phenotypes associated with response to positive airway pressure (PAP) therapy could help to redefine the standard treatment paradigm. The new PAP-RES (PAP-RESponsive) algorithm is based on the identification of OSA phenotypes that are likely to impact therapeutic goals and modalities. The paradigm shift is to propose a simplified approach that defines therapeutic goals based on OSA phenotype: from a predominantly "symptomatic phenotype" (individuals with high symptom burden that negatively impacts on daily life and/or accident risk or clinically significant insomnia) to a "vulnerable cardiovascular phenotype" (individuals with comorbidities [serious cardiovascular or respiratory disease or obesity] that have a negative impact on cardiovascular prognosis or a biomarker of hypoxic burden and/or autonomic nervous system dysfunction). Each phenotype requires a different PAP therapy care pathway based on differing health issues and treatment objectives.

Mild-to-moderate obstructive sleep apnea and mortality risk in a general population sample: The modifying effect of age and cardiovascular/cerebrovascular comorbidity

About 5.4%-45.7% of the general population has mild-to-moderate obstructive sleep apnea (mmOSA), which is highly comorbid with cardiovascular and/or cerebrovascular diseases (CBVD). We examined the association between mmOSA and all-cause mortality and the modifying effect of age and CBVD. A total of 1681 adults 20-88 years old from the Penn State Adult Cohort (PSAC) (41.9% male) were followed up for 20.1 ± 6.2 years for all-cause mortality. Mild and moderate OSA were defined as an apnea/hypopnea index (AHI) 5-14.9 and 15-29.9 events/hour, respectively. CBVD was defined as a report of a physician diagnosis or treatment for heart disease and/or stroke. Cox proportional hazards regression models were used to estimate all-cause mortality adjusted for confounders. All-cause mortality risk was significantly increased in the mmOSA group in young and middle-aged adults (<60 years) (HR = 1.59, 95%CI 1.08-2.04) but not in older adults (≥60 years) (HR = 1.05, 95%CI 0.80-1.39). A synergistic effect between mmOSA and CBVD was stronger in those <60 years (HR = 3.82, 95%CI 2.25-6.48 in <60 years vs 1.86 95%CI 1.14-3.04 in ≥60 years). There was an additive effect between moderate OSA and hypertension in <60 but not in those ≥60 years. Mild OSA was associated with all-cause mortality only in the presence of CBVD. Mortality risk is increased in young and middle-aged adults with moderate OSA, whereas the mortality risk associated with mild OSA is elevated only, regardless of age, in the presence of comorbid CBVD. AHI cut-offs warranting treatment of mmOSA may need to be adjusted based on age and comorbidities.

Apnea-hypopnea index and the polysomnographic risk factors for predicting 5- to 8-year mortality in patients with OSA

BACKGROUND

The purpose of this study was to investigate the long-term mortality rates of patients with obstructive sleep apnea (OSA) who received an overnight polysomnogram (PSG) for obtaining the diagnosis and to determine the relationship between PSG parameters and overall mortality.

METHODS

Between 2007 and 2013, patients who had overnight PSG and were diagnosed with OSA were included in the study. Factors which are thought to influence mortality were assessed for 5-year and overall survival using the log rank test and Kaplan-Meier survival curves. Using multivariable Cox regression analysis, a model was constructed for factors influencing 5-year and overall survival.

RESULTS

A total of 762 patients with a mean age of 52.7 (±10.8) and a dominance of men (74.7%) were studied. Gender, OSA severity subgroups, and apnea hypopnea index (AHI) were not statistically significantly associated with either 5-year or overall mortality (p<0.05 for both). Age, having a cardiovascular comorbidity, proportion of rapid eye movement (%REM), and total sleep time with an oxyhemoglobin saturation of less than 90% (T90) all showed a significant correlation with overall all-cause mortality in the model. For 5-year mortality and overall mortality, the hazard ration (HR) for T90 was 3.6 (95% CI (1.6-8.0) p=0.001) and 3 (95% CI (1.6-5.7) p=0.001), respectively.

CONCLUSION

The study findings suggest that not AHI but PSG parameters of hypoxia, mainly T90, having cardiovascular comorbidity, and %REM sleep were significant risk factors for all-cause mortality in patients with OSA. The association of OSA, hypoxia, and mortality is an area that deserves further study.

Review and perspective on sleep-disordered breathing research and translation to clinics

Sleep-disordered breathing, ranging from habitual snoring to severe obstructive sleep apnea, is a prevalent public health issue. Despite rising interest in sleep and awareness of sleep disorders, sleep research and diagnostic practices still rely on outdated metrics and laborious methods reducing the diagnostic capacity and preventing timely diagnosis and treatment. Consequently, a significant portion of individuals affected by sleep-disordered breathing remain undiagnosed or are misdiagnosed. Taking advantage of state-of-the-art scientific, technological, and computational advances could be an effective way to optimize the diagnostic and treatment pathways. We discuss state-of-the-art multidisciplinary research, review the shortcomings in the current practices of SDB diagnosis and management in adult populations, and provide possible future directions. We critically review the opportunities for modern data analysis methods and machine learning to combine multimodal information, provide a perspective on the pitfalls of big data analysis, and discuss approaches for developing analysis strategies that overcome current limitations. We argue that large-scale and multidisciplinary collaborative efforts based on clinical, scientific, and technical knowledge and rigorous clinical validation and implementation of the outcomes in practice are needed to move the research of sleep-disordered breathing forward, thus increasing the quality of diagnostics and treatment.

Age-related differences in the association of mild-to-moderate sleep apnea with incident cardiovascular and cerebrovascular diseases

BACKGROUND

Mild-to-moderate obstructive sleep apnea (mmOSA) is highly prevalent in the general population. However, studies on its association with incident cardiovascular and/or cerebrovascular disease (CBVD) are limited. We examined the association between mild-to-moderate OSA and incident cardiovascular and/or cerebrovascular (CBVD) in a general population sample, and whether age modifies this association.

METHODS

A total of 1173 adults from the Penn State Adult Cohort (20-88 years) without CBVD or severe OSA at baseline were followed-up after 9.2 (±4.1) years. Incident CBVD was defined based on a self-report of a physician diagnosis or treatment for heart disease and/or stroke. Logistic regression examined the association of mild-to-moderate OSA (AHI 5-29.9) with incident CBVD and the combined effect of mmOSA and MetS on incident CBVD after adjusting for multiple confounders.

RESULTS

Age significantly modified the association between mmOSA with incident CBVD (p-interaction = 0.04). Mild-to-moderate OSA was significantly associated with incident CBVD in adults aged <60 years (OR = 1.74, 95%CI = 1.06-2.88, p = 0.029), but not in adults aged ≥60 years (OR = 0.71, 95%CI = 0.39-1.27, p = 0.247). Even mild OSA (AHI 5-14.9) carried a significant risk for incident CBDV in adults aged <60 years (OR = 1.86, 95%CI = 1.05-3.28, p = 0.032). An additive effect was found between mmOSA and MetS with incident CBVD in those aged <65 years (OR = 3.84, 95%CI = 1.95-7.56, p<0.001).

CONCLUSIONS

The risk of incident CBVD is increased in young and middle-aged but not older adults with mmOSA, which may affect the way we currently diagnose and treat this highly prevalent sleep-related breathing disorder.

The Baveno Classification as a Predictor of CPAP Titration Pressure in Obstructive Sleep Apnea Syndrome

INTRODUCTION

Obstructive sleep apnea syndrome (OSAS) is a clinical condition characterised by repeated periods of partial or full obstruction of airflow throughout sleep, with impairment of the quality of life and increased mortality with socioeconomic impacts. CPAP therapy is a simple and effective treatment option for OSAS patients. To overcome the clinical and prognostic limitations of AHI-as a sole index of OSAS-the Baveno classification was recently set out and introduced into clinical practice. This study aims to analyse the effect of the Baveno classification on the optimum CPAP titration pressure.

METHODS

A retrospective analysis of the records of sleep studies in two centres between 2018 and 2021 was carried out. Patients diagnosed with OSAS and recruited for CPAP titration were included. Based on the Baveno classification, the patients were categorised into four groups (A, B, C, and D).

RESULTS

Consequently, 700 patients were analysed and 427 patients were included. A significant positive correlation was detected between the CPAP optimum titration pressure and OSAS severity, neck circumference, the oxygen desaturation index (ODI), mean oxygen saturation, the AHI, the BMI, and cumulative sleep time when the SpO2 was <90% (T90) on the other side (p: <0.0001). A non-significant correlation was seen between the Epworth Sleepiness Scale (ESS), symptom severity, end organ impact, and Baveno classification of the CPAP optimum titration pressure (p: 0.8, 0.4, 0.5, and 0.7, respectively).

CONCLUSIONS

The Baveno classification is not useful in the prediction of CPAP optimum titration pressure. However, the ODI and neck circumference were significant independent predictors of a higher CPAP titration pressure.

Clinical Application of the Multicomponent Grading System for Sleep Apnea Classification and Incident Cardiovascular Mortality

Objective  To evaluate the clinical utility of the Baveno classification in predicting incident cardiovascular mortality after five years of follow-up in a clinic-based cohort of patients with obstructive sleep apnea (OSA). Materials and Methods  We evaluated the reproducibility of the Baveno classification using data from the Santiago Obstructive Sleep Apnea (SantOSA) study. The groups were labeled Baveno A (minor symptoms and comorbidities), B (severe symptoms and minor comorbidities), C (minor symptoms and severe comorbidities), and D (severe symptoms and comorbidities). Within-group comparisons were performed using analysis of variance (ANOVA) and post hoc tests. The associations between groups and incident cardiovascular mortality were determined through the Mantel-Cox and Cox proportional hazard ratios (HRs) adjusted by covariables. Results  A total of 1,300 OSA patients were included (Baveno A: 27.7%; B: 28%; C: 16.8%; and D: 27.5%). The follow-up was of 5.4 years. Compared to Baveno A, the fully-adjusted risk of cardiovascular mortality with Baveno B presented an HR of 1.38 (95% confidence interval [95%CI]: 0.14-13.5; p  = 0.78); with Baveno C, it was of 1.71 (95%CI: 0.18-16.2; p  = 0.63); and, with Baveno D, of 1.04 (95%CI: 0.12-9.2; p  = 0.98). We found no interactions involving Baveno group, sex and OSA severity. Discussion  Among OSA patients, the Baveno classification can describe different subgroups. However, its utility in identifying incident cardiovascular mortality is unclear. Long-term follow-up studies and the inclusion of demographic variables in the classification could improve its ability to detect a high-risk phenotype associated with cardiovascular mortality. Conclusion  The Baveno classification serves as a valuable method for categorizing varying groups of patients afflicted with OSA. Nevertheless, its precision in identifying occurrence of cardiovascular mortality is still unclear.

Implementation of the Baveno Classification in Obstructive Sleep Apnea and Its Correlation with Symptoms of Anxiety and Depression

Background and Objectives: The Baveno classification represents a new approach to the assessment of the severity of OSA (Obstructive sleep apnea), which takes significant comorbidities into account: atrial fibrillation, arterial hypertension, heart failure, stroke, diabetes mellitus, and OSA symptoms expressed through the Epworth sleepiness scale (ESS). The authors believe that the Baveno classification facilitates a better stratification of patients with OSA and can be a good guide for deciding on the therapeutic approach and clinical monitoring of patients with OSA, compared to the AHI (apnea-hypopnea index) itself. The aim of this paper is to confirm the advantage of applying the Baveno classification to the evaluation of symptoms of anxiety and depression in the OSA patients compared to the application of the AHI as a single parameter. Materials and Methods: This research represents an observational retrospective study that was performed at the Pulmonology Clinic of the University Clinical Center in Kragujevac, Serbia. The study sample included 104 patients with diagnosed OSA. Patients were divided into four categories retrogradely according to the Baveno classification (A, B, C, and D). Statistical data processing was performed using the IBM SPSS Statistics version 25.0 program. Results: In our study, we proved that the Baveno classification is better at predicting the depressive disorder in OSA patients compared to the AHI itself, according to abnormal BDI-II (Beck Depression Inventory) score (value greater than ten) and HADS-D (Hospital anxiety and depression) scale (value greater than eight). The average AHI in the entire group of examined patients was 44.3 ± 19.8, while in category A the average AHI was 25.2 ± 10, in category B, 53.4 ± 20.6; in category C, 38.2 ± 18.5; and in category D, 48.1 ± 19.2. In the total sample, AHI did not correlate with the depressive episodes, but individually, the highest frequency of the depressive symptoms was precisely in the categories with the highest AHI (group D and B), where more than half of the subjects had an abnormal score. The frequency of the anxiety disorder (HADS-A) between the analyzed groups did not differ significantly, although the largest number of patients with significant anxiety were in category B, according to the Baveno classification. Conclusions: We proved that the Baveno classification is applicable in real life, and it is better at evaluating anxiety and depression using questionnaires and can identify new patients who need CPAP therapy, independently of other OSAS symptoms, primarily daytime sleepiness.

The role of oral appliance therapy in obstructive sleep apnoea

There is now widespread recognition within the world of sleep medicine of the increasing importance of dental sleep medicine and, in particular, the role of oral appliance therapy (OAT) in the management of adults with obstructive sleep apnoea (OSA). For the purpose of this review, the term OAT refers to a custom-made intra-oral appliance, which acts to posture the mandible in a forward and downward direction, away from its natural resting position. Whilst nasally applied continuous positive airway pressure remains the "gold standard" in nonsurgical OSA management, OAT remains the recognised alternative treatment.This review of OAT aims to provide an evidence-based update on our current understanding of their mode of action, exploring the potential anatomical and physiological impact of their use in preventing collapse of the upper airway; the current clinical practice guidelines, including the recently published National Institute of Clinical Excellence 2021 guidance, in conjunction with the American Academy of Sleep Medicine and American Academy of Dental Sleep Medicine; optimal design features, comparing the role of custom-made versus noncustom OAT devices and the importance of titration in achieving a dose-dependent effect; patient predictors, preference and adherence to OAT; its impact on a range of both patient- and clinician-centred health outcomes, with a comparison with CPAP; the limitations and side-effects of providing OAT; and, finally, a look at future considerations to help optimise the delivery and outcomes of OAT.

National Knowledge-Driven Management of Obstructive Sleep Apnea-The Swedish Approach

INTRODUCTION

This paper describes the development of "Swedish Guidelines for OSA treatment" and the underlying managed care process. The Apnea Hypopnea Index (AHI) is traditionally used as a single parameter for obstructive sleep apnea (OSA) severity classification, although poorly associated with symptomatology and outcome. We instead implement a novel matrix for shared treatment decisions based on available evidence.

METHODS

A national expert group including medical and dental specialists, nurses, and patient representatives developed the knowledge-driven management model. A Delphi round was performed amongst experts from all Swedish regions (N = 24). Evidence reflecting treatment effects was extracted from systematic reviews, meta-analyses, and randomized clinical trials.

RESULTS

The treatment decision in the process includes a matrix with five categories from a "very weak"" to "very strong" indication to treat, and it includes factors with potential influence on outcome, including (A) OSA-related symptoms, (B) cardiometabolic comorbidities, (C) frequency of respiratory events, and (D) age. OSA-related symptoms indicate a strong incitement to treat, whereas the absence of symptoms, age above 65 years, and no or well-controlled comorbidities indicate a weak treatment indication, irrespective of AHI.

CONCLUSIONS

The novel treatment matrix is based on the effects of treatments rather than the actual frequency of respiratory events during sleep. A nationwide implementation of this matrix is ongoing, and the outcome is monitored in a prospective evaluation by means of the Swedish Sleep Apnea Registry (SESAR).

Impact of Desaturation Patterns versus Apnea-Hypopnea Index in the Development of Cardiovascular Comorbidities in Obstructive Sleep Apnea Patients

Various phenotypes of obstructive sleep apnea (OSA) have been recently described and are poorly assessed by the commonly used polysomnographic indices, such as the apnea-hypopnea index and oxygen desaturation index. Nocturnal hypoxemia is the hallmark of OSA and new quantitative markers, as hypoxic burden or desaturation severity, have been shown to be associated with cardiovascular (CV) mortality. The purpose of this overview is to review the endophenotypical and clinical characteristics of OSA, the current metrics, and to analyze different measurements of hypoxemia in OSA to predict the cardiovascular impact (eg hypoxic burden). Potential interest of multidimensional models to classify OSA, such as BAVENO classification, is also discussed, with the goal of focusing on specific endophenotypes that are likely to develop CV comorbidities, in order to guide clinicians to more aggressive management of OSA in these individuals.

A Systematic Review of Sleep-Wake Disorder Diagnostic Criteria Reliability Studies

The aim of this article is to provide a systematic review of reliability studies of the sleep-wake disorder diagnostic criteria of the international classifications used in sleep medicine. Electronic databases (ubMed (1946-2021) and Web of Science (-2021)) were searched up to December 2021 for studies computing the Cohen's kappa coefficient of diagnostic criteria for the main sleep-wake disorder categories described in the principal classifications. Cohen's kappa coefficients were extracted for each main sleep-wake disorder category, for each classification subtype, and for the different types of methods used to test the degree of agreement about a diagnosis. The database search identified 383 studies. Fifteen studies were analyzed in this systematic review. Insomnia disorder (10/15) and parasomnia disorder (7/15) diagnostic criteria were the most studied. The reliability of all sleep-wake disorders presented a Cohen's kappa with substantial agreement (Cohen's kappa mean = 0.66). The two main reliability methods identified were "test-retest reliability" (11/15), principally used for International Classification of Sleep Disorders (ICSD), and "joint interrater reliability" (4/15), principally used for Diagnostic and Statistical Manual of Mental Disorders (DSM) subtype diagnostic criteria, in particularl, the DSM-5. The implications in terms of the design of the methods used to test the degree of agreement about a diagnosis in sleep medicine are discussed.

Current and Novel Treatment Options for OSA

Obstructive sleep apnoea is a challenging medical problem due to its prevalence, its impact on quality of life and performance in school and professionally, the implications for risk of accidents, and comorbidities and mortality. Current research has carved out a broad spectrum of clinical phenotypes and defined major pathophysiological components. These findings point to the concept of personalised therapy, oriented on both the distinct clinical presentation and the most relevant pathophysiology in the individual patient. This leads to questions of whether sufficient therapeutic options other than positive airway pressure (PAP) alone are available, for which patients they may be useful, if there are specific indications for single or combined treatment, and whether there is solid scientific evidence for recommendations. This review describes our knowledge on PAP and non-PAP therapies to address upper airway collapsibility, muscle responsiveness, arousability and respiratory drive. The spectrum is broad and heterogeneous, including technical and pharmaceutical options already in clinical use or at an advanced experimental stage. Although there is an obvious need for more research on single or combined therapies, the available data demonstrate the variety of effective options, which should replace the unidirectional focus on PAP therapy.

The analysis of individual pathophysiological composition opens new directions towards personalised treatment of OSA, focusing not only on pharyngeal dilation, but also on technical or pharmaceutical interventions on muscle function or breathing regulationhttps://bit.ly/3sayhkd

Defining obstructive sleep apnoea syndrome: a failure of semantic rules

Obstructive sleep apnoea syndrome (OSAS) is one of the most ubiquitous medical conditions in industrialised society. Since the recognition that symptoms of excessive daytime somnolence, problems with concentration, mood and cognitive impairment, as well as cardiometabolic abnormalities can arise as a consequence of obstructed breathing during sleep, it has been subject to variation in its definition. Over the past five decades, attempts have been made to standardise the definitions and scoring criteria used for apnoeas and hypopnoea, which are the hallmarks of obstructive sleep apnoea (OSA). However, applying these definitions in clinical and research practice has resulted in over- and under-estimation of the severity and prevalence of OSAS. Furthermore, the definitions may eventually become redundant in the context of rapid technological advances in breathing measurement and other signal acquisition. Increased efforts towards precision medicine have led to a focus on the pathophysiology of obstructed breathing during sleep. However, the same degree of effort has not been focused on how and why the latter does or does not result in diurnal symptoms, integral to the definition of OSAS. This review focuses on OSAS in adults and discusses some of the difficulties with current definitions and the possible reasons behind them.

The definition of obstructive sleep apnoea syndrome appears to be in constant flux dependent on the definitions attributed to its diagnostic componentshttps://bit.ly/3zXrWKg

OSA patients not treated with PAP - Evolution over 5 years according to the Baveno classification and cardiovascular outcomes

INTRODUCTION

The evolution of patients with obstructive sleep apnea (OSA) non-eligible for PAP-therapy at diagnosis is unknown. Currently, the severity of OSA is based on the apnea-hypopnea index (AHI), but its prognostic relevance has raised concerns. The Baveno classification may allow a better stratification of severity and therapeutic guidance in OSA.

METHODS

Patients with AHI≥5/h in 2015, classified into Baveno groups A and B and non-eligible for PAP therapy at diagnosis and over 5 years, were analyzed. Patients were reclassified into Baveno groups (A-D) and changes in groups over 5 years were explored. Patients in Baveno groups C and D, who developed major cardiovascular comorbidities (CVC) or end-organ damage (EOD group), were compared with patients in Baveno groups A and B (non-EOD group). To identify predictors of the development of major CVC or EOD, a logistic regression analysis was performed.

RESULTS

There were 76 patients, 58% male, mean age 51.9 ± 10.1 years, mean body mass index (BMI) of 30.3 ± 5.0 kg/m2 and median AHI of 8.9 (5.9-12.0) events/h. At diagnosis, 46% and 54% of patients were classified into Baveno group A and group B, respectively. In total, 21% of patients developed major CVC or EOD (Baveno group C or D); higher age (p = 0.011) and BMI (p = 0.004) and a higher percentage of central apneas (p = 0.012) at diagnosis significantly predicted it, while sex, sleepiness, insomnia, AHI, ODI and T90 were not.

CONCLUSIONS

A significant percentage of patients non-eligible for PAP-therapy at diagnosis of OSA developed CVC or EOD; higher age and BMI and a higher percentage of central apneas were significant predictors.

Arterial Stiffness Assessment Using the Arteriograph in Patients with Moderate-Severe OSA and Metabolic Syndrome-A Pilot Study

BACKGROUND

Both obstructive sleep apnea (OSA) and metabolic syndrome (MS) promote arterial stiffening. As a basis for this study, we presumed that arterial stiffness could be assessed using the Arteriograph (TensioMed, Budapest, Hungary) to detect early modifications induced by continuous positive airway therapy (CPAP) in reversing this detrimental vascular remodeling. Arterial stiffness is increasingly acknowledged as a major cardiovascular risk factor and a marker of subclinical hypertension-mediated organ damage. The aim of this pilot study was to evaluate the arterial stiffness changes in patients with moderate-severe OSA and MS after short-term CPAP use.

METHODS

We performed a prospective study that included patients with moderate-severe OSA and MS who had not undergone previous CPAP therapy. All subjects underwent clinical examination and arterial stiffness assessment using the oscillometric technique with Arteriograph (TensioMed, Budapest, Hungary) detection before and after 8-week CPAP therapy.

RESULTS

39 patients with moderate-severe OSA were included. Eight weeks of CPAP therapy significantly improved central systolic blood pressure (Δ = -11.4 mmHg, p = 0.009), aortic pulse wave velocity (aoPWV: Δ = -0.66 m/s, p = 0.03), and aortic augmentation index (aoAix: Δ = -8.25%, p = 0.01) only in patients who used the device for a minimum of 4 h/night (n = 20).

CONCLUSIONS

Arterial stiffness was improved only among CPAP adherent patients and could be detected using the Arteriograph (TensioMed, Budapest, Hungary), which involves a noninvasive procedure that is easy to implement for the clinical evaluation of arterial stiffness.

A Validation Study of Four Different Cluster Analyses of OSA and the Incidence of Cardiovascular Mortality in a Hispanic Population

BACKGROUND

Previous studies reported a strong association between sleepiness-related symptoms and comorbidities with poor cardiovascular outcomes among patients with moderate to severe OSA (msOSA). However, the validation of these associations in the Hispanic population from South America and the ability to predict incident cardiovascular disease remain unclear.

RESEARCH QUESTION

In Hispanic patients with msOSA, are four different cluster analyses reproducible and able to predict incident cardiovascular mortality?

STUDY DESIGN AND METHODS

Using the SantOSA cohort, we reproduced four cluster analyses (Sleep Heart Health Study [SHHS], Icelandic Sleep Apnea Cohort [ISAC], Sleep Apnea Cardiovascular Endpoints [SAVE], and The Institute de Recherche en Sante Respiratoire des Pays de la Loire [IRSR] cohorts) following a cluster analysis similar to each training dataset. The incidence of cardiovascular mortality was constructed using a Kaplan-Meier (log-rank) model, and Cox proportional hazards models were adjusted by confounders.

RESULTS

Among 780 patients with msOSA in our cohort, two previous cluster analyses (SHHS and ISAC) were reproducible. The SAVE and IRSR cluster analyses were not reproducible in our sample. We identified the following subtypes for SHHS: "minimally symptomatic," "disturbed sleep," "moderate sleepiness," and "severe sleepiness." For ISAC, three different subtypes ("minimally symptomatic," "disturbed sleep," and "excessive sleepiness") were similar to the original dataset. Compared with "minimally symptomatic," we found a significant association between "excessive sleepiness" and cardiovascular mortality after 5 years of follow-up in SantOSA, hazard ratio (HR), 5.47; 95%CI, 1.74-8.29; P < .01; and HR, 3.23; 95%CI, 1.21-8.63; P = .02, using the SHHS and ISAC cluster analyses, respectively.

INTERPRETATION

Among patients with msOSA, a symptom-based approach can validate different OSA patient subtypes, and those with excessive sleepiness have an increased risk of incident cardiovascular mortality in the Hispanic population from South America.

International Consensus Document on Obstructive Sleep Apnea

The main aim of this international consensus document on obstructive sleep apnea is to provide guidelines based on a critical analysis of the latest literature to help health professionals make the best decisions in the care of adult patients with this disease. The expert working group was formed primarily of 17 scientific societies and 56 specialists from a wide geographical area (including the participation of 4 international societies), an expert in methodology, and a documentalist from the Iberoamerican Cochrane Center. The document consists of a main section containing the most significant innovations and a series of online manuscripts that report the systematic literature searches performed for each section of the international consensus document. This document does not discuss pediatric patients or the management of patients receiving chronic non-invasive mechanical ventilation (these topics will be addressed in separate consensus documents).