Impact of sleep apnea on economics

Is C-reactive protein elevated in obstructive sleep apnea? a systematic review and meta-analysis

Purpose: This study examined whether circulating C-reactive protein (CRP) is elevated in obstructive sleep apnoea (OSA) independent of the confounding effects of comorbidities, smoking, body mass index (BMI), age and gender. Methods: A systematic review of the literature was performed using PubMed, Embase and Cochrane databases from 1 January 1997 to 1 November 2017 using the key words obstructive sleep apnoea and C-Reactive protein to identify full text English language studies that compared CRP in adult non-smoking OSA participants without comorbidities and adult healthy non-smoking control participants matched for BMI, age and gender. Data from eligible studies were subjected to meta-analysis using RevMan version 5.3. Results: Five studies (219 OSA participants, 116 controls) met the selection criteria. The total standard mean difference for circulating high sensitivity CRP was 0.61 mg/dL higher in OSA participants than in control participants (confidence interval: 0.38 to 0.84, p < 0.00001), with low between-studies heterogeneity (df = 7, p = 0.16, I² = 33%) and minimal evidence of publication bias. Conclusions: CRP levels in non-smoking OSA participants without comorbidities were increased relative to levels in healthy matched non-smoking control participants, suggesting that pharyngeal or systemic inflammatory effects attributable to OSA may elevate CRP.

The Impact of Treatments for OSA on Monetized Health Economic Outcomes: A Systematic Review

OBJECTIVE

To review systematically the published literature regarding the impact of treatment for OSA on monetized health economic outcomes.

METHODS

Customized structured searches were performed in PubMed, Embase (Embase.com), and the Cochrane Central Register of Controlled Trials (Wiley) databases. Reference lists of eligible studies were also analyzed. Titles and abstracts were examined, and articles were identified for full-text review. Studies that met inclusion criteria were evaluated in detail, and study characteristics were extracted using a standardized template. Quantitative characteristics of the studies were summarized, and a qualitative synthesis was performed.

RESULTS

Literature searches identified 2,017 nonredundant abstracts, and 196 full-text articles were selected for review. Seventeen studies met inclusion criteria and were included in the final synthesis. Seven studies included formal cost-effectiveness or cost-utility analyses. Ten studies employed cohort designs, and four studies employed randomized controlled trial or quasi-experimental designs. Positive airway pressure was the most common treatment modality, but oral appliances and surgical approaches were also included. The most common health economic outcomes were health-care use (HCU) and quality-adjusted life years (QALYs). Follow-ups ranged from 6 weeks to 5 years. Overall, 15 of 18 comparisons found that treatment of OSA resulted in a positive economic impact. Treatment adherence and OSA severity were positively associated with cost-effectiveness.

CONCLUSIONS

Although study methodologies varied widely, evidence consistently suggested that treatment of OSA was associated with favorable economic outcomes, including QALYs, within accepted ranges of cost-effectiveness, reduced HCU, and reduced monetized costs.

Distance to Specialist Medical Care and Diagnosis of Obstructive Sleep Apnea in Rural Saskatchewan

Obstructive sleep apnea (OSA) is the most common sleep-disordered breathing condition. Patients with OSA symptoms are often not diagnosed clinically, which is a concern, given the health and safety risks associated with unmanaged OSA. The availability of fewer practicing medical specialists combined with longer travel distances to access health care services results in barriers to diagnosis and treatment in rural communities. This study aimed to (1) determine whether the proportion of adults reporting OSA symptoms in the absence of a sleep apnea diagnosis in rural populations varied by travel distance to specialist medical care and (2) assess whether any distance-related patterns were attributable to differences in the frequency of diagnosis among adults who likely required this specialist medical care. We used a cross-sectional epidemiologic study design, augmented by analysis of follow-up survey data. Our study base included adults who completed a 2010 baseline questionnaire for the Saskatchewan Rural Health Study. Follow-up occurred until 2015. 6525 adults from 3731 households constituted our sample. Statistical models used log-binomial regression. Rural adults who reported the largest travel distances (≥250 km) to specialist medical care were 1.17 (95% CI: 1.07, 1.29) times more likely to report OSA symptoms in the absence of a sleep apnea diagnosis than those who reported the smallest (<100 km; referent) distances. However, the proportion of sleep apnea diagnoses was low and unaffected by reported travel distance among adults who likely required this specialist medical care. Our findings suggest factors other than travel distance may be contributing to the low sleep apnea diagnostic rate. This remains important as undiagnosed and untreated OSA has serious implications on the health of people and populations, but effective treatments are available. Health care access barriers to the diagnosis and treatment of OSA require evaluation to inform health care planning and delivery.

Indicadores de adiposidade como método de rastreamento para polissonografia em trabalhadores de turno

Resumo Objetivo: verificar o potencial discriminatório dos indicadores de adiposidade na predição da apneia obstrutiva do sono (AOS) em trabalhadores de turnos. Métodos: estudo transversal realizado em uma empresa de extração de minério de ferro, em Minas Gerais, Brasil. Dados antropométricos foram coletados e polissonografia (PSG) foi realizada em 118 trabalhadores de turno do sexo masculino que possuíam ao menos um fator de risco global para doença cardiovascular. Resultados: a prevalência de AOS na amostra foi de 84,7%. Entre os indicadores de adiposidade usados para predizerem a AOS (≥ 5 eventos/hora), o índice de massa corporal (IMC), a circunferência da cintura (CC), a relação cintura/estatura (RCE) e a gordura corporal total (GCT), revelaram valores de sensibilidade acima de 70%. Gordura visceral (GV), circunferência do pescoço (CP) e relação pescoço-estatura (RPE) foram as mais efetivas em identificar corretamente trabalhadores sem AOS (valores de especificidade acima de 70%). As áreas sob a curva de Característica de Operação do Receptor (COR) para CC e RPE foram maiores que 0,7, o que indicou que o teste foi eficaz na discriminação de indivíduos com AOS. Conclusões: alterações nos indicadores de adiposidade abdominal e cervical têm relação significativa com a presença de AOS e demostraram eficácia como método de rastreamento para PSG. CC e RPE são considerados bons indicadores para predizerem a AOS.

Comparison of apnoea-hypopnoea index and oxygen desaturation index when identifying obstructive sleep apnoea using type-4 sleep studies

The concordance of different indices from type-4 sleep studies in diagnosing and categorising the severity of obstructive sleep apnoea is not known. This is a critical gap as type-4 sleep studies are used to diagnose obstructive sleep apnoea in some settings. Therefore, we aimed to determine the concordance between flow-based apnoea-hypopnoea index (AHI_flow50% ) and oxygen desaturation index (ODI_3% ) by measuring them concurrently. Using a random sub-sample of 296 from a population-based cohort who underwent two-channel type-4 sleep studies, we assessed the concordance between AHI_flow50% and ODI_3% . We compared the prevalence of obstructive sleep apnoea of various severities as identified by the two methods, and determined their concordance using coefficient Kappa(κ). Participants were aged (mean ± SD) 53 ± 0.9 years (48% male). The body mass index was 28.8 ± 5.2 kg m^-2 and neck circumference was 37.4 ± 3.9 cm. The median AHI_flow50% was 5 (inter-quartile range 2, 10) and median ODI_3% was 9 (inter-quartile range 4, 15). The obstructive sleep apnoea prevalence reported using AHI_flow50% was significantly lower than that reported using ODI_3% at all severity thresholds. Although 90% of those with moderate-severe obstructive sleep apnoea classified using AHI_flow50% were identified by using ODI_3% , only 46% of those with moderate-severe obstructive sleep apnoea classified using ODI_3% were identified by AHI_flow50% . The overall concordance between AHI_flow50% and ODI_3% in diagnosing and classifying the severity of obstructive sleep apnoea was only fair (κ = 0.32), better for males (κ = 0.42 [95% confidence interval 0.32-0.57] versus 0.22 [95% confidence interval 0.09-0.31]), and lowest for those with a body mass index ≥ 35 (κ = 0.11). In conclusion, ODI_3% and AHI_flow50% from type-4 sleep studies are at least moderately discordant. Until further evidence is available, the use of ODI_3% as the measure of choice for type-4 sleep studies is recommended cautiously.

TNFRSF11B: A potential plasma biomarker for diagnosis of obstructive sleep apnea

BACKGROUND

Obstructive sleep apnea (OSA) was characterized by chronic intermittent hypoxia, which was an independent risk factor for endothelial dysfunction. Circulating TNFRSF11B might play an important role in promoting endothelial cells dysfunction. We explored the role of plasma TNFRSF11B as a potential mechanism of endothelial dysfunction in OSA patients.

METHODS

The study population consisted of 120 patients with varying severity of OSA and 40 control subjects. Plasma TNFRSF11B levels were measured using human Magnetic Luminex assay.

RESULTS

Our data showed that plasma TNFRSF11B levels were significantly higher in patients with OSA. After adjusting confounding factors, plasma TNFRSF11B levels were independently associated with the presence of OSA (Beta:0.434, 95% CI: 664.096 to 1076.247; P < 0.001) and plasma TNFRSF11B levels were positively associated with the apnea-hypopnea index (Beta:0.486, 95% CI: 0.007 to 0.017; P < 0.001). Furthermore, plasma TNFRSF11B showed higher discriminatory accuracy in predicting the presence of OSA (AUC:0.964).

CONCLUSIONS

Plasma TNFRSF11B levels were significantly associated with the presence of OSA and its severity. TNFRSF11B could be a plasma biomarker with a positive diagnostic value for premature vascular endothelial dysfunction in patients with OSA.

Connexins and Atrial Fibrillation in Obstructive Sleep Apnea

PURPOSE OF THE REVIEW

To summarize the potential interactions between obstructive sleep apnea (OSA), atrial fibrillation (AF), and connexins.

RECENT FINDINGS

OSA is highly prevalent in patients with cardiovascular disease, and is associated with increased risk for end-organ substantial morbidities linked to autonomic nervous system imbalance, increased oxidative stress and inflammation, ultimately leading to reduced life expectancy. Epidemiological studies indicate that OSA is associated with increased incidence and progression of coronary heart disease, heart failure, stroke, as well as arrhythmias, particularly AF. Conversely, AF is very common among subjects referred for suspected OSA, and the prevalence of AF increases with OSA severity. The interrelationships between AF and OSA along with the well-known epidemiological links between these two conditions and obesity may reflect shared pathophysiological pathways, which may depend on the intercellular diffusion of signaling molecules into either the extracellular space or require cell-to-cell contact. Connexin signaling is accomplished via direct exchanges of cytosolic molecules between adjacent cells at gap membrane junctions for cell-to-cell coupling. The role of connexins in AF is now quite well established, but the impact of OSA on cardiac connexins has only recently begun to be investigated. Understanding the biology and regulatory mechanisms of connexins in OSA at the transcriptional, translational, and post-translational levels will undoubtedly require major efforts to decipher the breadth and complexity of connexin functions in OSA-induced AF.

SUMMARY

The risk of end-organ morbidities has initiated the search for circulating mechanistic biomarker signatures and the implementation of biomarker-based algorithms for precision-based diagnosis and risk assessment. Here we summarize recent findings in OSA as they relate to AF risk, and also review potential mechanisms linking OSA, AF and connexins.

International consensus (ICON) on the ENT role in diagnosis of obstructive sleep apnea syndrome

During the 2017 IFOS ENT World Congress, an international expert panel was asked to clarify the role of ENT in the diagnosis process of the obstructive sleep apnea syndrome (OSA) in adults around the world. OSA is a major public health issue throughout the world. OSA is a highly prevalent disease with heavy clinical, social and economical outcomes. This high prevalence raises serious difficulties of diagnosis accessibility if only somnologists are able to confirm OSA diagnosis. First of all, the panellists reviewed the impact of OSA. Secondly, they defined the ENT role stressing ENT legitimacy, professional expertise and academic and institutional tasks. They also defined when somnologists were necessary. For the international panel, the ENT is a major player in the OSA diagnosis process.

Cost-effectiveness strategies in OSAS management: a short review

Obstructive sleep apnoea (OSAS) is an underdiagnosed chronic disease with a high prevalence in adults. It is becoming a significant social problem, since it is associated with a worsening in quality of life and increase in mortality. The cost-effectiveness ratio of diagnostic and therapeutic management of OSAS is a strategic issue to counteract the expected increasing demand of objective testing. OSAS patients with any clinical evidence of comorbidities must be studied using simplified and less expensive systems such as Home Sleep Testing (HST). On the other hand, Sleep Laboratory Polysomnography (PSG) is the gold standard to manage OSAS patients with comorbidities. It should be pointed out that the use of HST can lead to incorrect diagnosis in poorly selected OSAS subjects. This short review discusses various topics for the proper diagnosis and treatment of OSAS in view of epidemiological factors and results in terms of costs and social benefit of the disease. Whatever the strategy chosen and/or the organisational model adopted for managing OSAS, it cannot and should not take into account only cost-effectiveness. Long-term prospective studies evaluating cost-effectiveness ratios and outcomes of OSAS treatment of hospital management models versus home care models are needed.

Predictors of Sleep Apnea in the Canadian Population

Older age, obesity, hypertension, snoring, and excessive daytime sleepiness have been associated with sleep apnea. The objective of this study was to determine the prevalence (crude and adjusted), as well as the risk factors, of sleep apnea in the adult Canadian population. Data from the 2009 Sleep Apnea Rapid Response (SARR) questionnaire were used to identify the risk factors, and all sleep-related questions in the SARR questionnaire were used. The outcome variable of interest was health professional-diagnosed sleep apnea. Covariates of interest were demographic variables, population characteristics, respiratory and cardiovascular diseases, and enabling resources. The multiple logistic regression model adjusted for the clustering effect was used to analyze the data. Sleep apnea was diagnosed in 858,913 adults (3.4% of the population), and more men (65.4%) than women (34.6%) were diagnosed with sleep apnea. Multivariable logistic regression analysis indicated that age (45 and older), loud snoring, sudden awakening with gasping/choking (rare/sometimes and once or more a week), and nodding off/falling asleep in driving in the past 12 months were significantly associated with diagnosed sleep apnea. Predictive probability demonstrated that in overweight and obese persons, ≥15 minutes of daily exercise significantly decreased the risk of diagnosed sleep apnea. The conclusion of this study is that in the Canadian population, sleep apnea is associated with older age, loud snoring, and sleeping problems. The protective effect of exercise warrants further investigation.

Obstructive sleep apnea and the metabolic syndrome: The road to clinically-meaningful phenotyping, improved prognosis, and personalized treatment

Obstructive sleep apnea (OSA) is an increasingly prevalent sleep disorder characterized by upper airway obstruction during sleep, resulting in breathing pauses, intermittent hypoxia, and fragmented sleep. In parallel, the constellation of adverse health outcomes associated with prolonged obesity, such as insulin resistance, elevated blood pressure, triglycerides, and reduced high-density lipoprotein cholesterol - termed metabolic syndrome -raises the risk of cardiovascular morbidity and mortality, type 2 diabetes, and all-cause mortality. Affecting 35-40% of U.S. adults, risk factors for metabolic syndrome, including obesity, middle age, sedentary behavior, and genetics, share considerable overlap with those for OSA. Thus, it has been difficult to disentangle cause, effect, and whether certain treatments, such as CPAP, can improve these outcomes. In this paper, we provide an update to our 2005 review which explored the association between OSA and metabolic syndrome, highlighting visceral obesity as the common etiological factor of both conditions. This update includes (a) recent data on physiological and biochemical mechanisms, (b) new data in nonobese men and women as well as children and adolescents, (c) insight from the latest treatment studies, (d) the role of aging in understanding clinically-meaningful phenotypes of the disorder, and (e) the potential diagnostic/prognostic utility of biomarkers in identifying OSA patients with the strongest cardiometabolic risk.

Psychological distress in patients with obstructive sleep apnoea: The role of hostility and coping self-efficacy

We aimed to assess whether hostility and coping self-efficacy are associated with psychological distress in obstructive sleep apnoea patients. Furthermore, we examined whether coping self-efficacy mediates the association between hostility and psychological distress. We included 150 obstructive sleep apnoea patients (Apnoea-Hypopnoea Index ⩾5; 68% male; mean age: 48.9 ± 9.5 years). Regression models showed that hostility and poor coping self-efficacy were strongly associated with psychological distress in obstructive sleep apnoea patients. All assessed coping self-efficacy dimensions mediated the association between hostility and psychological distress. Coping self-efficacy for stopping unpleasant emotions and thoughts showed the strongest association with a lower level of psychological distress.

Phenotype-Based and Self-Learning Inter-Individual Sleep Apnea Screening With a Level IV-Like Monitoring System

Purpose: We propose a phenotype-based artificial intelligence system that can self-learn and is accurate for screening purposes and test it on a Level IV-like monitoring system.

Methods: Based on the physiological knowledge, we hypothesize that the phenotype information will allow us to find subjects from a well-annotated database that share similar sleep apnea patterns. Therefore, for a new-arriving subject, we can establish a prediction model from the existing database that is adaptive to the subject. We test the proposed algorithm on a database consisting of 62 subjects with the signals recorded from a Level IV-like wearable device measuring the thoracic and abdominal movements and the SpO2.

Results: With the leave-one-subject-out cross validation, the accuracy of the proposed algorithm to screen subjects with an apnea-hypopnea index greater or equal to 15 is 93.6%, the positive likelihood ratio is 6.8, and the negative likelihood ratio is 0.03.

Conclusion: The results confirm the hypothesis and show that the proposed algorithm has potential to screen patients with SAS.

Social support, mastery, sleep-related problems and their association with functional status in untreated obstructive sleep apnoea patients

BACKGROUND

Social support and mastery are important aspects in the treatment of chronic diseases, however their role in connection with Obstructive Sleep Apnoea (OSA) remains unclear.

OBJECTIVES

The study examined the associations between social support, mastery, sleep-related problems and functional status in untreated OSA patients.

METHODS

All patients in this cross-sectional study completed the Multidimensional Scale of Perceived Social Support, the Pearlin Mastery Scale, the Pittsburgh Sleep Quality Index, the Epworth Sleepiness Scale and the Functional Outcomes of Sleep Questionnaire. Multiple linear regression and mediation analyses were used to analyse the data.

RESULTS

Participants were 150 newly diagnosed OSA patients (Apnoea-Hypopnoea Index-AHI≥5; 68% male; mean age 48.9 ± 9.5years). Compared with social support, mastery was more strongly associated with functional status. The indirect effects of sleep-related problems on functional status via mastery varied between 17.7% and 23.3%.

CONCLUSIONS

Supporting OSA patients' sense of mastery may significantly contribute to better disease management.

Occupation and Obstructive Sleep Apnea: A Meta-Analysis

OBJECTIVE

Obstructive sleep apnea (OSA) remains a prevalent condition, but its occupational burden is unclear. We carried out a systematic review to characterize the consistency and magnitude of occupational associations with OSA.

METHODS

We studied OSA within three occupational categories: commercial drivers, organic solvent-exposed workers, other selected occupations. We performed a meta-analysis on the prevalence of OSA among drivers and the risk of OSA associated with solvent exposure.

RESULTS

The pooled OSA prevalence in drivers was 41% (95% confidence interval [CI] 26% to 56%) for apnea hypopnea-index (AHI) is greater than 5, and 15% (95% CI 12% to 19%) for AHI is greater than 15. Exposure to solvents was associated with increased but non-statistically significant risk of OSA: summary relative risk, 2.38 (95% CI 0.89 to 6.32). Evidence of occupational association was inconsistent for other factors.

CONCLUSIONS

OSA is common among commercial drivers and potentially associated with occupations involving likely solvent exposure.

Suicidal ideation in patients with obstructive sleep apnoea and its relationship with disease severity, sleep-related problems and social support

We aimed to assess the prevalence of suicidal ideation and to examine the relationships between obstructive sleep apnoea severity, sleep-related problems, social support and suicidal ideation in obstructive sleep apnoea patients. We included 149 patients (68% male; mean age, 48.99 ± 9.57 years) with diagnosed obstructive sleep apnoea (Apnoea–Hypopnoea Index ⩾5) based on full-night polysomnography. The prevalence of suicidal ideation among obstructive sleep apnoea patients was 20.1 per cent. Structural equation modelling showed that suicidal ideation in obstructive sleep apnoea was strongly related to poor sleep quality and high fatigue levels. No relationship between social support and suicidal ideation in obstructive sleep apnoea patients was found.

Sleep-Disordered Breathing-Do We Have to Change Gears in Heart Failure?

The majority of patients with heart failure have sleep-disordered breathing (SDB)—with central (rather than obstructive) sleep apnoea becoming the predominant form in those with more severe disease. Cyclical apnoeas and hypopnoeas are associated with sleep disturbance, hypoxaemia, haemodynamic changes, and sympathetic activation. Such patients have a worse prognosis than those without SDB. Mask-based therapies of positive airway pressure targeted at SDB can improve measures of sleep quality and partially normalise the sleep and respiratory physiology, but recent randomised trials of cardiovascular outcomes in central sleep apnoea have been neutral or suggested the possibility of harm, likely from increased sudden death. Further randomised outcome studies (with cardiovascular mortality and hospitalisation endpoints) are required to determine whether mask-based treatment for SDB is appropriate for patients with chronic systolic heart failure and obstructive sleep apnoea, for those with heart failure with preserved ejection fraction, and for those with decompensated heart failure. New therapies for sleep apnoea—such as implantable phrenic nerve stimulators—also require robust assessment. No longer can the surrogate endpoints of improvement in respiratory and sleep metrics be taken as adequate therapeutic outcome measures in patients with heart failure and sleep apnoea.

[Vascular dysfunction in obstructive sleep apnoea: Implication of microparticules]

Obstructive sleep apnea (OSA) is associated with increased cardiovascular diseases, including myocardial infarction and stroke and promotes cardiovascular risk factors including diabetes and hypertension. OSA has also been proposed to have a direct proatherogenic effects. Recent studies have investigated the role of microparticles (MPs) in the atherogenic process. MPs are small plasma membrane vesicles that can be released by a variety of vascular or blood cells and that contain membrane and cytosolic elements. Case-control studies have suggested that OSA is associated with an increase in circulating platelet-, endothelial- and leukocyte-derived MPs. MPs from OSA patients injected to mice have also been shown to induce vascular inflammation and endothelial dysfunction. In this article, we provide an overview of the main characteristics of MPs expressed in OSA and their potential role in the atherogenic process.

[Sleep apneas, metabolic syndrome and cardiovascular risk: Data from the Pays de la Loire sleep cohort]

Obstructive sleep apnea-hypopnea syndrome (OSAHS) is a prevalent disease characterized by recurrent episodes of partial or complete obstruction of upper airway during sleep. Untreated moderate to severe OSAHS is recognized as a cardiovascular (CV) risk factor. Data from the Pays de la Loire sleep cohort and other clinic- or population-based cohorts demonstrate a strong association between OSAHS and the different components of the metabolic syndrome including systemic hypertension, diabetes and impaired lipid metabolism. Beside sleep-disordered breathing severity, these factors contribute to increase the risk of CV events in OSAHS patients. Continuous positive airway pressure (CPAP) therapy of OSAHS is associated with a modest but clinically significant blood pressure reduction. Conversely, there is no clear evidence in support of a metabolic impact of CPAP in OSAHS patients. Considering the multifactorial pathophysiology of CV risk in OSAHS patients and the beneficial impact of various lifestyle and pharmacologic interventions on blood pressure and metabolic dysfunction, combined modality therapy is a promising strategy to improve CV outcomes in individuals with OSAHS.

Sleep apnea: a review of diagnostic sensors, algorithms, and therapies

While public awareness of sleep related disorders is growing, sleep apnea syndrome (SAS) remains a public health and economic challenge. Over the last two decades, extensive controlled epidemiologic research has clarified the incidence, risk factors including the obesity epidemic, and global prevalence of obstructive sleep apnea (OSA), as well as establishing a growing body of literature linking OSA with cardiovascular morbidity, mortality, metabolic dysregulation, and neurocognitive impairment. The US Institute of Medicine Committee on Sleep Medicine estimates that 50-70 million US adults have sleep or wakefulness disorders. Furthermore, the American Academy of Sleep Medicine (AASM) estimates that more than 29 million US adults suffer from moderate to severe OSA, with an estimated 80% of those individuals living unaware and undiagnosed, contributing to more than $149.6 billion in healthcare and other costs in 2015. Although various devices have been used to measure physiological signals, detect apneic events, and help treat sleep apnea, significant opportunities remain to improve the quality, efficiency, and affordability of sleep apnea care. As our understanding of respiratory and neurophysiological signals and sleep apnea physiological mechanisms continues to grow, and our ability to detect and process biomedical signals improves, novel diagnostic and treatment modalities emerge.

OBJECTIVE

This article reviews the current engineering approaches for the detection and treatment of sleep apnea.

APPROACH

It discusses signal acquisition and processing, highlights the current nonsurgical and nonpharmacological treatments, and discusses potential new therapeutic approaches.

MAIN RESULTS

This work has led to an array of validated signal and sensor modalities for acquiring, storing and viewing sleep data; a broad class of computational and signal processing approaches to detect and classify SAS disease patterns; and a set of distinctive therapeutic technologies whose use cases span the continuum of disease severity.

SIGNIFICANCE

This review provides a current perspective of the classes of tools at hand, along with a sense of their relative strengths and areas for further improvement.

Association between sleep apnea and low bone mass in adults: a systematic review and meta-analysis

We performed a systematic review of the literature to assess the association between sleep apnea and bone metabolism diseases including osteoporosis in adult population. Results from clinical trials suggest that the association between sleep apnea and low bone mass in adults is possible.

INTRODUCTION

This study aimed to synthesize existing evidence on the potential association between sleep apnea and low bone mass in adults.

METHODS

Electronic searches of five databases were performed. The inclusion criteria consisted of studies in humans that assessed potential associations between sleep apnea and bone metabolic diseases in an adult population. For diagnosis of sleep apnea overnight polysomnography, home polygraphy, or validated records from healthcare databases were considered. Reduced bone density, osteoporosis, serum/urinary levels for markers of bone formation and resorption, or risk of fractures caused without history of trauma were considered indicators of low bone mass. A random-effects model meta-analysis was applied when possible.

RESULTS

Of the 963 relevant references, 12 studies met our inclusion criteria and were assessed to be of medium to low bias. Nine out of 12 studies reported an association between sleep apnea and low bone mass (increased bone resorption markers, reduced bone density, and higher risk of osteoporosis). Two studies did not report a significant association, whereas one study reported an increase of bone density in sleep apnea patients compared to non-sleep apnea patients. Meta-analysis of 2 studies (n = 112,258 patients) showed that sleep apnea was a significant risk factor for osteoporosis (odds ratio (OR), 1.92; 95%CI, 1.24 to 2.97; I² = 66%); females only had an OR of 2.56 (95% CI, 1.96 to 3.34; I² = 0%) while the OR in males was 2.03 (95% CI, 1.24 to 3.35; I² = 38%).

CONCLUSIONS

An association between sleep apnea and low bone mass in adults is plausible, but supporting evidence has a risk of bias and is inconsistent.

Prediction of the severity of obstructive sleep apnea by anthropometric features via support vector machine

To develop an applicable prediction for obstructive sleep apnea (OSA) is still a challenge in clinical practice. We apply a modern machine learning method, the support vector machine to establish a predicting model for the severity of OSA. The support vector machine was applied to build up a prediction model based on three anthropometric features (neck circumference, waist circumference, and body mass index) and age on the first database. The established model was then valided independently on the second database. The anthropometric features and age were combined to generate powerful predictors for OSA. Following the common practice, we predict if a subject has the apnea-hypopnea index greater then 15 or not as well as 30 or not. Dividing by genders and age, for the AHI threhosld 15 (respectively 30), the cross validation and testing accuracy for the prediction were 85.3% and 76.7% (respectively 83.7% and 75.5%) in young female, while the negative likelihood ratio for the AHI threhosld 15 (respectively 30) for the cross validation and testing were 0.2 and 0.32 (respectively 0.06 and 0.1) in young female. The more accurate results with lower negative likelihood ratio in the younger patients, especially the female subgroup, reflect the potential of the proposed model for the screening purpose and the importance of approaching by different genders and the effects of aging.

Quality-of-life improvement after endoscopic sinus surgery in patients with obstructive sleep apnea

BACKGROUND

There is preliminary evidence that patients with chronic rhinosinusitis (CRS) and comorbid obstructive sleep apnea (OSA) have reduced quality-of-life (QOL) improvements after functional endoscopic sinus surgery (FESS) compared with patients without OSA. The effect of OSA severity on QOL improvement after FESS is unknown.

OBJECTIVES

To better characterize the QOL improvement after FESS for patients with comorbid OSA and to assess whether QOL improvement is dependent on OSA severity.

METHODS

This multi-institution, retrospective cohort study evaluated adult patients with CRS who underwent FESS between 2007 and 2015. Preoperative, 1-month, 3-month, 6-month, and 1-year postoperative 22-Item Sino-Nasal Outcome Test scores were used to evaluate QOL. We compared patients without OSA with patients with stratified OSA based on the preoperative apnea-hypopnea index. A multilevel, mixed-effects linear regression model was used for the analysis.

RESULTS

Of 480 participants, 83 (17%) had OSA, and 47 of these patients had polysomnography results available for review. Both patients with OSA and patients without OSA reported significant QOL improvement after surgery (p < 0.0001) relative to baseline. In the unadjusted model, the subjects with OSA demonstrated a statistically worse outcome in 22-Item Sino-Nasal Outcome Test scores at each time point (2.4 points higher per time point, p = 0.006). When controlling for covariates, the adjusted model showed no difference in QOL outcome based on OSA status (p = 0.114). When stratified by OSA disease severity, the adjusted model showed no difference in the QOL outcome.

CONCLUSIONS

Patients with CRS and comorbid OSA had worse QOL outcomes after FESS; however, when controlling for patient factors, there was no difference in QOL outcome. OSA disease severity did not seem to predict QOL improvement after FESS.

Sleep disordered breathing in pregnancy: the maternal and fetal implications

Sleep disordered breathing (SDB) which includes obstructive sleep apnoea (OSA) and upper airway resistance syndrome (UARS), has emerged as a risk factor for adverse maternal-foetal outcomes in pregnancy. Physiological changes of pregnancy predispose a woman 'at risk' towards developing SDB. The increasing incidence of OSA in pregnancy closely correlates with the population trends of obesity. Common screening tools validated in non-pregnant subjects including Epworth Sleepiness Scale (ESS) and Berlin Questionnaire (BQ) are poor predictors of SDB in pregnancy. Preeclampsia, gestational hypertension and gestational diabetes mellitus (GDM) are linked with SDB. Preeclampsia and OSA share common pathological associations. It is unclear if one predisposes the other. Foetal morbidity includes intrauterine growth restriction (IUGR), preterm delivery, low birth weight, neonatal intensive care unit (NICU) admission and Apgar score of less than seven at one minute. Continuous positive airway pressure (CPAP) is a well-documented treatment of SDB in pregnancy and has been shown to reverse some of the adverse events. It becomes imperative to diagnose and manage this condition as OSA causes substantial morbidity in the untreated pregnant patient and foetus. Three short clinical cases and a literature review on SDB on pregnancy are presented.

Sleep Disturbances among Older Adults in the United States, 2002-2012: Nationwide Inpatient Rates, Predictors, and Outcomes

Objective/Background: We examined the rates, predictors, and outcomes [mortality risk (MR), length of stay (LOS), and total charges (TC)] of sleep disturbances in older hospitalized patients.

Patients/Methods: Using the U.S. Nationwide Inpatient Sample database (2002–2012), older patients (≥60 years) were selected and rates of insomnia, obstructive sleep apnea (OSA) and other sleep disturbances (OSD) were estimated using ICD-9CM. TC, adjusted for inflation, was of primary interest, while MR and LOS were secondary outcomes. Multivariable regression analyses were conducted.

Results: Of 35,258,031 older adults, 263,865 (0.75%) had insomnia, 750,851 (2.13%) OSA and 21,814 (0.06%) OSD. Insomnia rates increased significantly (0.27% in 2002 to 1.29 in 2012, P-trend < 0.001), with a similar trend observed for OSA (1.47 in 2006 to 5.01 in 2012, P-trend < 0.001). TC (2012 $) for insomnia-related hospital admission increased over time from $22,250 in 2002 to $31,527 in 2012, and increased similarly for OSA and OSD; while LOS and MR both decreased. Women with any sleep disturbance had lower MR and TC than men, while Whites had consistently higher odds of insomnia, OSA, and OSD than older Blacks and Hispanics. Co-morbidities such as depression, cardiovascular risk factors, and neurological disorders steadily increased over time in patients with sleep disturbances.

Conclusion: TC increased over time in patients with sleep disturbances while LOS and MR decreased. Further, research should focus on identifying the mechanisms that explain the association between increasing sleep disturbance rates and expenditures within hospital settings and the potential hospital expenditures of unrecognized sleep disturbances in the elderly.

Sleep Apnea and Cancer: Analysis of a Nationwide Population Sample

STUDY OBJECTIVES

Epidemiological evidence from relatively small cohorts suggests that obstructive sleep apnea (OSA) is associated with higher cancer incidence and mortality. Here we aimed to determine whether cancer incidence for major cancer types and risk of metastases or mortality from cancer are increased in the presence of OSA.

METHODS

All OSA diagnoses included in an employee-sponsored health insurance database spanning the years 2003-2012 were identified and 1:1 matched demographically based on age, gender, and state of residence, or alternatively matched by comorbidities. The incidence of 12 types of cancer was assessed. In addition, another cohort of patients with a primary diagnosis of cancer was retrieved, and the risk of metastatic disease or cancer mortality was determined as a function of the presence or absence of OSA. Multivariate Cox proportional hazards regression models were fitted to assess the independent associations between OSA and outcomes of interest.

RESULTS

Based on a cohort of ∼5.6 million individuals, the incidence of all cancer diagnoses combined was similar in OSA and retrospectively matched cases. However, the adjusted risk of pancreatic and kidney cancer and melanoma were significantly higher in patients with OSA, while the risk of colorectal, breast, and prostate cancers appeared to be lower. Among individuals with a diagnosis of cancer, the presence of OSA was not associated with an increased risk for metastasis or death.

CONCLUSIONS

In a large nationally representative health insurance database, OSA appears to increase the risk for only a very selective number of cancer types, and does not appear to be associated with an increased risk of metastatic cancer or cancer-related deaths.

Evaluation of the add-on NOWAPI® medical device for remote monitoring of compliance to Continuous Positive Airway Pressure and treatment efficacy in obstructive sleep apnea

Background

Optimizing the measurement of Continuous Positive Airway Pressure (CPAP) compliance and treatment efficacy is paramount for patients with obstructive sleep apnea syndrome (OSAS). Compliance knowledge is currently based on data coming from CPAP machines; however algorithms and measured parameters vary from one machine to another. This study was conducted to clinically evaluate a novel device, NOWAPI^®, designed to assess compliance remotely in conjunction with any CPAP machine. NOWAPI^® was tested against polygraphy, the gold standard for the measurement of CPAP treatment duration and residual apnea-hypopnea index (AHI).

Methods

Single group assignment, open label, non-randomized. Sleep laboratory setting. 22 adult patients with OSAS treated by CPAP were included. Recordings were performed during one night while the patient was treated with his/her usual CPAP and interface. NOWAPI^® data were collected electronically and compared to data acquisition and visual scoring using an EMBLETTA^® GOLD polygraph. Statistics were only descriptive.

Results

Recordings were performed with six different CPAP machines and three different interfaces (full facemask, nasal pillow, nasal mask). The median [Q1; Q3] absolute difference in CPAP treatment duration between NOWAPI^® and polygraphy was of 1.0 min [0.0; 12.0], corresponding to a relative difference of 0.21 % [0.0; 2.2] (Per Protocol data set, n = 20). NOWAPI^® tended to underestimate residual AHI in a magnitude of two events per hour as compared to polygraphy. The device was well tolerated and the patient satisfaction was good.

Conclusions

This clinical study confirmed prior bench tests, showing that NOWAPI^® estimate of CPAP treatment duration was clinically acceptable and in agreement with polygraphy. Although a limited number of OSAS patients treated by CPAP were included, relevant findings for the device improvement were identified.

Trial Registration ClinicalTrials.gov identifier: NCT01441622. The study was funded by Air Liquide HealthCare

The effect of sex and age on the comorbidity burden of OSA: an observational analysis from a large nationwide US health claims database

Obstructive sleep apnoea (OSA) is a highly prevalent condition but studies exploring the burden of OSA-associated comorbidities have been limited by small sample sizes with underrepresentation of women.

We queried the Truven Health MarketScan Research Databases 2003–2012, which is a collection of health insurance claims for working adults and retirees with employer-sponsored health insurance. Adults with a diagnostic code for OSA with at least 12 months of follow-up from the index date of OSA diagnosis were compared to a matched random sample. Comorbidities were assessed using International Classification of Diseases, Ninth Edition, codes. A logistic regression model was constructed to test the independent association between OSA and comorbidities.

Our cohort included 1 704 905 patients with OSA and 1 704 417 matched controls. All comorbidities were significantly more prevalent in OSA patients. Type 2 diabetes and ischaemic heart disease were more prevalent in men but hypertension and depression were more prevalent in women with OSA. In contrast, the sex differences in the prevalence of congestive heart failure, arrhythmias and stroke were less pronounced. The prevalence of comorbidities increased with age but the effect of age varied based on the specific comorbidity. The divergence between OSA and controls was more pronounced after the sixth decade of life for most cardiovascular diseases (i.e.heart failure, ischaemic heart disease, stroke and arrhythmias), while depression exhibited an opposite trend. In a fully adjusted model, the odds of all comorbidities were significantly increased in OSA patients.

In a large, nationally representative sample of working and retired people, OSA is strongly associated with significant comorbidities in both men and women with unique sex differences emerging.

Biomarkers associated with obstructive sleep apnea: A scoping review

The overall validity of biomarkers in the diagnosis of obstructive sleep apnea (OSA) remains unclear. We conducted a scoping review to provide assessments of biomarkers characteristics in the context of obstructive sleep apnea (OSA) and to identify gaps in the literature. A scoping review of studies in humans without age restriction that evaluated the potential diagnostic value of biological markers (blood, exhaled breath condensate, salivary, and urinary) in the OSA diagnosis was undertaken. Retained articles were those focused on the identification of biomarkers in subjects with OSA, the latter being confirmed with a full overnight or home-based polysomnography (PSG). Search strategies for six different databases were developed. The methodology of selected studies was classified using an adaptation of the evidence quality criteria from the American Academy of Pediatrics. Additionally the biomarkers were classified according to their potential clinical application. We identified 572 relevant studies, of which 117 met the inclusion criteria. Eighty-two studies were conducted in adults, 34 studies involved children, and one study had a sample composed of both adults and children. Most of the studies evaluated blood biomarkers. Potential diagnostic biomarkers were found in nine pediatric studies and in 58 adults studies. Only nine studies reported sensitivity and specificity, which varied substantially from 43% to 100%, and from 45% to 100%, respectively. Studies in adults have focused on the investigation of IL-6, TNF-α and hsCRP. There was no specific biomarker that was tested by a majority of authors in pediatric studies, and combinatorial urine biomarker approaches have shown preliminary promising results. In adults IL-6 and IL-10 seem to have a favorable potential to become a good biomarker to identify OSA.

Clinical consequences and economic costs of untreated obstructive sleep apnea syndrome

Objective

To provide an overview of the healthcare and societal consequences and costs of untreated obstructive sleep apnea syndrome.

Data sources

PubMed database for English-language studies with no start date restrictions and with an end date of September 2014.

Methods

A comprehensive literature review was performed to identify all studies that discussed the physiologic, clinical and societal consequences of obstructive sleep apnea syndrome as well as the costs associated with these consequences. There were 106 studies that formed the basis of this analysis.

Conclusions

Undiagnosed and untreated obstructive sleep apnea syndrome can lead to abnormal physiology that can have serious implications including increased cardiovascular disease, stroke, metabolic disease, excessive daytime sleepiness, work-place errors, traffic accidents and death. These consequences result in significant economic burden. Both, the health and societal consequences and their costs can be decreased with identification and treatment of sleep apnea.

Implications for practice

Treatment of obstructive sleep apnea syndrome, despite its consequences, is limited by lack of diagnosis, poor patient acceptance, lack of access to effective therapies, and lack of a variety of effective therapies. Newer modes of therapy that are effective, cost efficient and more accepted by patients need to be developed.

Measurement properties of patient-reported outcome measures (PROMs) in adults with obstructive sleep apnea (OSA): A systematic review

This systematic review summarizes the evidence regarding the quality of patient-reported outcome measures (PROMs) validated in patients with obstructive sleep apnea (OSA). We performed a systematic literature search of all PROMs validated in patients with OSA, and found 22 measures meeting our inclusion criteria. The quality of the studies was assessed using the consensus-based standards for the selection of health status measurement instruments (COSMIN) checklist. The results showed that most of the measurement properties of the PROMs were not, or not adequately, assessed. For many identified PROMs there was no involvement of patients with OSA during their development or before the PROM was tested in patients with OSA. Positive exceptions and the best current candidates for assessing health status in patients with OSA are the sleep apnea quality of life index (SAQLI), Maugeri obstructive sleep apnea syndrome (MOSAS) questionnaire, Quebec sleep questionnaire (QSQ) and the obstructive sleep apnea patient-oriented severity index (OSAPOSI). Even though there is not enough evidence to fully judge the quality of these PROMs as outcome measure, when interpreted with caution, they have the potential to add value to clinical research and clinical practice in evaluating aspects of health status that are important to patients.

Referral Patterns and Positive Airway Pressure Adherence upon Diagnosis of Obstructive Sleep Apnea

OBJECTIVE

Obstructive sleep apnea (OSA) is a serious medical condition that adds to patient morbidity and mortality. Treatment with positive airway pressure (PAP) is the standard of care, but many patients refuse or do not tolerate PAP. Little is known about the subsequent management of these patients. We sought to understand what types of treatment, if any, adult patients with OSA receive who either fail or refuse PAP therapy within our institution.

STUDY DESIGN

Retrospective chart review.

SETTING

Academic hospital.

SUBJECTS

All adult patients undergoing polysomnogram during the months of March and April 2010 (n = 1174) who were diagnosed with OSA.

METHODS

The electronic medical record was reviewed to determine the subsequent management of patients with a diagnosis of OSA, including tolerance or failure of PAP and referral to specialists upon intolerance.

RESULTS

Of 1174 patients, 616 met inclusion criteria. Ultimately, 260 (42%) had documented adherence to PAP. Of 241 untreated patients, 84 patients (35%) were referred for further attempts at management of diagnosed OSA. Nearly half of patients with diagnosed OSA did not have continued treatment or referral.

CONCLUSION

To our knowledge, this is the first study to define the subsequent management of patients who have failed or refused PAP. Despite the known sequelae of OSA, clinicians are not treating a significant percentage of patients with diagnosed OSA. Those who fail to tolerate PAP therapy are unlikely to be referred for additional treatment. Therapies other than PAP may be warranted in this population.

An Economic Evaluation of Home Versus Laboratory-Based Diagnosis of Obstructive Sleep Apnea

STUDY OBJECTIVES

We conducted an economic analysis of the HomePAP study, a multicenter randomized clinical trial that compared home-based versus laboratory-based testing for the diagnosis and management of obstructive sleep apnea (OSA).

DESIGN

A cost-minimization analysis from the payer and provider perspectives was performed, given that 3-mo clinical outcomes were equivalent.

SETTING

Seven academic sleep centers.

PARTICIPANTS

There were 373 subjects at high risk for moderate to severe OSA.

INTERVENTIONS

Subjects were randomized to either home-based limited channel portable monitoring followed by unattended autotitration with continuous positive airway pressure (CPAP), versus a traditional pathway of in-laboratory sleep study and CPAP titration.

MEASUREMENTS AND RESULTS

From the payer perspective, per subject costs for the laboratory-based pathway were $1,840 (95% confidence interval [CI] $1,660, $2,015) compared to $1,575 (95% CI $1,439, $1,716) for the home-based pathway under the base case. Costs were $264 (95% CI $39, $496, P = 0.02) in favor of the home arm. From the provider perspective, per subject costs for the laboratory arm were $1,697 (95% CI $1,566, $1,826) compared to $1,736 (95% CI $1,621, $1,857) in the home arm, for a difference of $40 (95% CI -$213, $142, P = 0.66) in favor of the laboratory arm under the base case. The provider operating margin was $142 (95% CI $85, $202,P < 0.01) in the laboratory arm, compared to a loss of -$161 (95% CI -$202, -$120, P < 0.01) in the home arm.

CONCLUSIONS

For payers, a home-based diagnostic pathway for obstructive sleep apnea with robust patient support incurs fewer costs than a laboratory-based pathway. For providers, costs are comparable if not higher, resulting in a negative operating margin.

CLINICALTRIALSGOV IDENTIFIER

NCT00642486.

Clinical effectiveness and cost-effectiveness results from the randomised controlled Trial of Oral Mandibular Advancement Devices for Obstructive sleep apnoea-hypopnoea (TOMADO) and long-term economic analysis of oral devices and continuous positive airway pressure

BACKGROUND

Obstructive sleep apnoea-hypopnoea (OSAH) causes excessive daytime sleepiness (EDS), impairs quality of life (QoL) and increases cardiovascular disease and road traffic accident risks. Continuous positive airway pressure (CPAP) treatment is clinically effective but undermined by intolerance, and its cost-effectiveness is borderline in milder cases. Mandibular advancement devices (MADs) are another option, but evidence is lacking regarding their clinical effectiveness and cost-effectiveness in milder disease.

OBJECTIVES

(1) Conduct a randomised controlled trial (RCT) examining the clinical effectiveness and cost-effectiveness of MADs against no treatment in mild to moderate OSAH. (2) Update systematic reviews and an existing health economic decision model with data from the Trial of Oral Mandibular Advancement Devices for Obstructive sleep apnoea-hypopnoea (TOMADO) and newly published results to better inform long-term clinical effectiveness and cost-effectiveness of MADs and CPAP in mild to moderate OSAH.

TOMADO

A crossover RCT comparing clinical effectiveness and cost-effectiveness of three MADs: self-moulded [SleepPro 1™ (SP1); Meditas Ltd, Winchester, UK]; semibespoke [SleepPro 2™ (SP2); Meditas Ltd, Winchester, UK]; and fully bespoke [bespoke MAD (bMAD); NHS Oral-Maxillofacial Laboratory, Addenbrooke's Hospital, Cambridge, UK] against no treatment, in 90 adults with mild to moderate OSAH. All devices improved primary outcome [apnoea-hypopnoea index (AHI)] compared with no treatment: relative risk 0.74 [95% confidence interval (CI) 0.62 to 0.89] for SP1; relative risk 0.67 (95% CI 0.59 to 0.76) for SP2; and relative risk 0.64 (95% CI 0.55 to 0.76) for bMAD (p < 0.001). Differences between MADs were not significant. Sleepiness [as measured by the Epworth Sleepiness Scale (ESS)] was scored 1.51 [95% CI 0.73 to 2.29 (SP1)] to 2.37 [95% CI 1.53 to 3.22 (bMAD)] lower than no treatment (p < 0.001), with SP2 and bMAD significantly better than SP1. All MADs improved disease-specific QoL. Compliance was lower for SP1, which was unpopular at trial exit. At 4 weeks, all devices were cost-effective at £20,000/quality-adjusted life-year (QALY), with SP2 the best value below £39,800/QALY.

META-ANALYSIS

A MEDLINE, EMBASE and Science Citation Index search updating two existing systematic reviews (one from November 2006 and the other from June 2008) to August 2013 identified 77 RCTs in adult OSAH patients comparing MAD with conservative management (CM), MADs with CPAP or CPAP with CM. MADs and CPAP significantly improved AHI [MAD -9.3/hour (p < 0.001); CPAP -25.4/hour (p < 0.001)]. Effect difference between CPAP and MADs was 7.0/hour (p < 0.001), favouring CPAP. No trials compared CPAP with MADs in mild OSAH. MAD and CPAP reduced the ESS score similarly [MAD 1.6 (p < 0.001); CPAP 1.6 (p < 0.001)].

LONG-TERM COST-EFFECTIVENESS

An existing model assessed lifetime cost-utility of MAD and CPAP in mild to moderate OSAH, using the revised meta-analysis to update input values. The TOMADO provided utility estimates, mapping ESS score to European Quality of Life-5 Dimensions three-level version for device cost-utility. Using SP2 as the standard device, MADs produced higher mean costs and mean QALYs than CM [incremental cost-effectiveness ratio (ICER) £6687/QALY]. From a willingness to pay (WTP) of £15,367/QALY, CPAP is cost-effective, although the likelihood of MADs (p = 0.48) and CPAP (p = 0.49) being cost-effective is very similar. Both were better than CM, but there was much uncertainty in the choice between CPAP and MAD (at a WTP £20,000/QALY, the probability of being the most cost-effective was 47% for MAD and 52% for CPAP). When SP2 lifespan increased to 18 months, the ICER for CPAP compared with MAD became £44,066. The ICER for SP1 compared with CM was £1552, and for bMAD compared with CM the ICER was £13,836. The ICER for CPAP compared with SP1 was £89,182, but CPAP produced lower mean costs and higher mean QALYs than bMAD. Differential compliance rates for CPAP reduces cost-effectiveness so MADs become less costly and more clinically effective with CPAP compliance 90% of SP2.

CONCLUSIONS

Mandibular advancement devices are clinically effective and cost-effective in mild to moderate OSAH. A semi-bespoke MAD is the appropriate first choice in most patients in the short term. Future work should explore whether or not adjustable MADs give additional clinical and cost benefits. Further data on longer-term cardiovascular risk and its risk factors would reduce uncertainty in the health economic model and improve precision of effectiveness estimates.

TRIAL REGISTRATION

This trial is registered as ISRCTN02309506.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 18, No. 67. See the NIHR Journals Library website for further project information.

Biomarkers associated with obstructive sleep apnea and morbidities: a scoping review

OBJECTIVE

To map potential biomarkers of obstructive sleep apnea (OSA)-associated morbidities in both adults and children, to identify gaps in current evidence, and to determine the value of conducting a full systematic review.

METHODS

A scoping review was undertaken of studies in patients with OSA that evaluated the potential value of biological markers in identifying OSA-associated morbidities. Retained articles were only those studies whose main objective was to identify morbidity biomarkers in subjects with OSA, the latter being confirmed with a full overnight polysomnography (PSG) in a laboratory or at-home settings. The methodology of the selected studies was classified using an adaptation of the evidence quality criteria recommended by the American Academy of Pediatrics. Additionally the biomarkers were categorized according to their potential clinical applicability.

RESULTS

572 citations were identified of which 48 met inclusion criteria. Thirty-four studies were conducted in adults and 14 involved children. Most of the studies evaluated blood biomarkers, and presented 31 potential diagnostic biomarkers.

CONCLUSION

The majority of studies that performed explored blood-based biomarkers, with most not identifying definitive morbidity biomarkers. Of the potentially promising morbidity biomarkers, plasma IL-6 and high sensitivity C-reactive protein appear to exhibit a favorable profile, and may discriminate OSA patients with and without morbidities in both adults and children. MRP 8/14 was retained in children as well as cardiovascular morbidity-associated biomarker. Urinary neurotransmitters may also provide a good tool for screening OSA cognitive morbidity in children.

Obstructive sleep apnea and metabolic bone disease: insights into the relationship between bone and sleep

Obstructive sleep apnea (OSA) and low bone mass are two prevalent conditions, particularly among older adults-a section of the U.S. population that is expected to grow dramatically over the coming years. OSA, the most common form of sleep-disordered breathing, has been linked to multiple cardiovascular, metabolic, hormonal, and inflammatory derangements and may have adverse effects on bone. However, little is known about how OSA (including the associated hypoxia and sleep loss) affects bone metabolism. In order to gain insight into the relationship between sleep and bone, we review the growing information on OSA and metabolic bone disease and discuss the pathophysiological mechanisms by which OSA may affect bone metabolism/architecture.