Sleep Architecture in Patients With Primary Snoring and Obstructive Sleep Apnea

Gut microbiome composition changes in obstructive sleep apnoea syndrome also in relation to excessive daytime sleepiness

INTRODUCTION

Obstructive sleep apnoea syndrome (OSAS) is considered a risk factor for several comorbidities. Alteration in gut microbiome was documented in OSAS animal models and in paediatric patients. This study analysed gut microbiome composition in adult patients with OSAS compared to healthy controls. Further, the effect of excessive daytime sleepiness (EDS) on gut microbiome was evaluated.

METHODS

Adult patients with OSAS underwent polysomnographic recording and completed the Epworth Sleepiness Scale (ESS) to assess EDS. Faecal samples were collected and compared between patients and healthy controls. Composition, community diversity, differences in taxa abundance profiles and sample dysbiosis were evaluated through 16S metagenomics and multiple bioinformatics algorithms. OSAS patients were distributed in two groups according to EDS (ESS score≥10) to assess differences in clinical, polysomnographic and faecal data.

RESULTS

Twenty-three OSAS patients were compared to 44 healthy controls. Patients presented significant differences of gut microbiome biodiversity, specifically in qualitative alpha diversity metrics (Faith's PD Kruskal-Wallis test, p-value=0.003; Number_of_Observed_Features, p-value =0.001). OSAS patients tend to cluster together, at least for Jaccard and Unweighted UniFrac distance-based PERMANOVA tests (q-values=0.02 and =0.003, respectively). Several taxa were detected as different in abundance between OSAS patients and healthy controls, although, globally, OSAS patients cannot be considered as "dysbiotic". Differences in bacteria composition were evident between OSAS patients with and those without EDS.

CONCLUSIONS

OSAS is associated with gut microbiome alteration in adult patients. EDS in OSAS seems to characterize a different gut microbiome composition, although it can be only hypothesized a gut-mediated effect on EDS in OSAS.

Advancing Sleep Disorder Diagnostics: A Transformer-Based EEG Model for Sleep Stage Classification and OSA Prediction

Sleep disorders, particularly Obstructive Sleep Apnea (OSA), have a considerable effect on an individual's health and quality of life. Accurate sleep stage classification and prediction of OSA are crucial for timely diagnosis and effective management of sleep disorders. In this study, we develop a sequential network that enhances sleep stage classification by incorporating self-attention mechanisms and Conditional Random Fields (CRF) into a deep learning model comprising multi-kernel Convolutional Neural Networks (CNNs) and Transformer-based encoders. The self-attention mechanism enables the model to focus on the most discriminative features extracted from single-channel electroencephalography (EEG) recordings, while the CRF module captures the temporal dependencies between sleep stages, improving the model's ability to learn more plausible sleep stage sequences. Moreover, we explore the relationship between sleep stages and OSA severity by utilizing the predicted sleep stage features to train various regression models for Apnea-Hypopnea Index (AHI) prediction. Our experiments demonstrate an improved sleep stage classification performance of 78.7%, particularly on datasets with diverse AHI values, and highlight the potential of leveraging sleep stage information for monitoring OSA. By employing advanced deep learning techniques, we thoroughly explore the intricate relationship between sleep stages and sleep apnea, laying the foundation for more precise and automated diagnostics of sleep disorders.

Automated remote sleep monitoring needs uncertainty quantification

Wearable electroencephalography devices emerge as a cost-effective and ergonomic alternative to gold-standard polysomnography, paving the way for better health monitoring and sleep disorder screening. Machine learning allows to automate sleep stage classification, but trust and reliability issues have hampered its adoption in clinical applications. Estimating uncertainty is a crucial factor in enhancing reliability by identifying regions of heightened and diminished confidence. In this study, we used an uncertainty-centred machine learning pipeline, U-PASS, to automate sleep staging in a challenging real-world dataset of single-channel electroencephalography and accelerometry collected with a wearable device from an elderly population. We were able to effectively limit the uncertainty of our machine learning model and to reliably inform clinical experts of which predictions were uncertain to improve the machine learning model's reliability. This increased the five-stage sleep-scoring accuracy of a state-of-the-art machine learning model from 63.9% to 71.2% on our dataset. Remarkably, the machine learning approach outperformed the human expert in interpreting these wearable data. Manual review by sleep specialists, without specific training for sleep staging on wearable electroencephalography, proved ineffective. The clinical utility of this automated remote monitoring system was also demonstrated, establishing a strong correlation between the predicted sleep parameters and the reference polysomnography parameters, and reproducing known correlations with the apnea-hypopnea index. In essence, this work presents a promising avenue to revolutionize remote patient care through the power of machine learning by the use of an automated data-processing pipeline enhanced with uncertainty estimation.

Reduced Oxygen Extraction Fraction as a Biomarker for Cognitive Deficits in Obstructive Sleep Apnea

BACKGROUND

Obstructive sleep apnea (OSA) is characterized by disruptive breathing, resulting in a decline in cognitive performance. This study investigates the role of oxygen extraction fraction (OEF) and quantitative susceptibility mapping (QSM) in OSA-related cognitive impairment.

METHODS

The study recruited 15 patients with confirmed OSA and 16 healthy controls, who underwent overnight polysomnography and brain MRI using a 3 Tesla machine and 64-channel head coil. A two-step MRI analysis was employed to measure OEF. QSM was first created by processing separate phase and magnitude images. OEF maps were then generated by identifying veins based on their susceptibility. Volumetric analysis was performed using the FreeSurfer. Neuropsychological tests were administered to evaluate cognition.

RESULTS

The analysis of OEF revealed significantly lower values in various cerebral cortical regions of OSA patients than in controls. Notably, OEF in the cerebral cortex and frontal, temporal, and occipital regions showed negative correlations with the duration of stage N2 sleep (highest correlation between N2 and right temporal OEF: p = 0.005, r = -0.681). Furthermore, poorer performance on neuropsychological tests, such as the backward digit span test, was significantly correlated with reduced OEF in the left hemisphere (p = 0.016), left cerebral cortex (p = 0.019), right frontal (p = 0.034), left frontal (p = 0.014), left parietal (p = 0.008), left temporal (p = 0.048), and left occipital lobes (p = 0.015). No significant differences in QSM or brain volume were observed.

CONCLUSIONS

Decreased OEF emerges as a potential biomarker for cognitive deficits in OSA, suggesting disturbances in cerebral oxygen metabolism may underlie cognitive impairments. These findings underscore the importance of investigating physiological markers in understanding OSA-related cognitive dysfunction.

Polysomnographic features of children with obesity: body mass index predict severe obstructive sleep apnea in obese children?

BACKGROUND

Few studies have explored the polysomnographic features of children with obesity.

PURPOSE

This study aimed to explore the demographic and polysomnographic features of obese children and determine whether body mass index (BMI) could predict severe obstructive sleep apnea (OSA).

METHODS

This cross-sectional study recruited obese children who underwent diagnostic polysomnography between January 2019 and March 2022. We explored demographic and anthropometric measures as well as polysomnographic abnormalities among them. We used receiver operating characteristic curves and logistic regression analyses to determine the optimal cutoff values of anthropometric variables for predicting severe OSA.

RESULTS

A total of 132 children with obesity (76.5% male; mean age, 12.5±3.2 years) were included. Severe OSA was identified in 64 children (48.5%). Desaturation was observed in 59.8%, while 23.5% had hyperarousal, 20.5% had sleep-related hypoventilation, 60.6% had positional OSA, 40.2% had rapid eye movement-related OSA, and 5.0% had obesity hypoventilation syndrome. Among them, BMI (odds ratio [OR], 1.11; 95% confidence interval [CI], 1.05-1.17; P<0.001), neck circumference (OR, 1.15; 95% CI, 1.07-1.25; P<0.001), and waist circumference (OR, 1.04; 95% CI, 1.02- 1.07; P=0.001) were significantly associated with severe OSA. These findings suggest a cutoff BMI for predicting severe OSA of greater than 29.2 kg/m2 with 81.3% sensitivity and 48.5% specificity.

CONCLUSION

Severe OSA is common in children with obesity; thus, we recommend screening children with obesity and a BMI greater than 29.2 kg/m2 for severe OSA.

The efficacy and safety of dual orexin receptor antagonists in obstructive sleep apnea: A systematic review and meta-analysis of randomised controlled trials

Dual orexin receptor antagonists (DORAs) are indicated for the treatment of insomnia disorder. However, DORAs may change sleep parameters, thus having adverse effects on patients with obstructive sleep apnea (OSA). This meta-analysis clarified the impact of DORAs in OSA treatment on sleep architecture and respiratory parameters. We systematically searched PubMed, Embase, and Cochrane Central databases for randomised control trials published up to May 2024. The search focussed on studies discussing the effects of DORAs on sleep architecture in patients with OSA. Nonrandomised studies were excluded. A meta-analysis using a random-effects model was performed. The patients were categorised into subgroups based on the treatment protocol (single or multiple dosages). The Cochrane risk of bias tool for randomised trials assessed the risk of bias. Our meta-analysis included four randomised placebo-controlled trials, encompassing 126 patients with a mean age of 49.1 years. The effects of DORAs on sleep architecture and respiratory parameters were examined. The main findings were as follows: DORAs significantly increased the total sleep time and improved sleep efficiency. However, they did not affect rapid eye movement sleep. DORAs also showed a trend towards decreased wake after sleep onset and did not increase the apnea-hypopnea index. DORAs did not increase the percentage of total sleep time with oxygen saturation lower than 90% and 85% compared with placebo, respectively. Furthermore, DORAs were not associated with significantly higher adverse effects compared with placebo. This meta-analysis demonstrated that DORAs improve sleep and do not impair nighttime respiratory function in patients with OSA.

Associations of baseline obstructive sleep apnea and sleep macroarchitecture with cognitive function after 8 years in middle-aged and older men from a community-based cohort study

Previous prospective studies examining associations of obstructive sleep apnea and sleep macroarchitecture with future cognitive function recruited older participants, many demonstrating baseline cognitive impairment. This study examined obstructive sleep apnea and sleep macroarchitecture predictors of visual attention, processing speed, and executive function after 8 years among younger community-dwelling men. Florey Adelaide Male Ageing Study participants (n = 477) underwent home-based polysomnography, with 157 completing Trail-Making Tests A and B and the Mini-Mental State Examination. Associations of obstructive sleep apnea (apnea-hypopnea index, oxygen desaturation index, and hypoxic burden index) and sleep macroarchitecture (sleep stage percentages and total sleep time) parameters with future cognitive function were examined using regression models adjusted for baseline demographic, biomedical, and behavioural factors, and cognitive task performance. The mean (standard deviation) age of the men at baseline was 58.9 (8.9) years, with severe obstructive sleep apnea (apnea-hypopnea index ≥30 events/h) in 9.6%. The median (interquartile range) follow-up was 8.3 (7.9-8.6) years. A minority of men (14.6%) were cognitively impaired at baseline (Mini-Mental State Examination score <28/30). A higher percentage of light sleep was associated with better Trail-Making Test A performance (B = -0.04, 95% confidence interval [CI] -0.06, -0.01; p = 0.003), whereas higher mean oxygen saturation was associated with worse performance (B = 0.11, 95% CI 0.02, 0.19; p = 0.012). While obstructive sleep apnea and sleep macroarchitecture might predict cognitive decline, future studies should consider arousal events and non-routine hypoxaemia measures, which may show associations with cognitive decline.

The effects of exercise programs on sleep architecture in obstructive sleep apnea: a meta-analysis of randomized controlled trials

OBJECTIVES

Exercise is an effective intervention for obstructive sleep apnea (OSA). However, the effects of exercise on objective sleep architecture in patients with OSA remain unknown. This meta-analysis aimed to collect data from randomized controlled trials of exercise interventions in patients with OSA, with a specific focus on objective sleep parameters derived from polysomnography.

METHODS

Randomized control trials that targeted patients with OSA aged >18 years, measured sleep using polysomnography after exercise programs, and reported the proportion of sleep stages were included for meta-analysis. Bias was assessed using the revised Cochrane risk-of-bias tool and funnel plots. The random effects model was applied.

RESULTS

Six studies with a total of 236 patients were included in the meta-analysis. There were no significant differences in the total sleep time (TST), sleep efficiency, sleep onset latency, stage N1 sleep, or rapid eye movement sleep between the exercise and control groups. Participation in an exercise program lasting >12 weeks significantly decreased stage N2 and increased stage N3 sleep as observed in the subgroup analysis. Although this tendency did not reach statistical significance in the total-group analysis, it was significant after excluding the possible confounding effects of heart disease.

CONCLUSIONS

The exercise program decreased N2 and increased N3 proportions over the TST among patients with OSA, which may correspond to subjective sleep quality. The beneficial effects were significant when the program lasted >12 weeks and after excluding the confounding effects of heart disease. Exercise program duration should be considered when providing clinical advice.

Altered sleep architecture in diabetes and prediabetes: findings from the Baependi Heart Study

STUDY OBJECTIVES

People with diabetes and prediabetes are more likely to have sleep-disordered breathing (SDB), but few studies examined sleep architecture in people with diabetes or prediabetes in the absence of moderate-severe SDB, which was the aim of our cross-sectional study.

METHODS

This cross-sectional sample is from the Baependi Heart Study, a family-based cohort of adults in Brazil. About 1074 participants underwent at-home polysomnography (PSG). Diabetes was defined as fasting glucose >125 mg/dL or HbA1c > 6.4 mmol/mol or taking diabetic medication, and prediabetes was defined as HbA1c ≥ 5.7 & <6.5 mmol/mol or fasting glucose ≥ 100 & ≤125 mg/dl. We excluded participants with an apnea-hypopnea index (AHI) ≥ 30 in primary analyses and ≥ 15 in secondary analysis. We compared sleep stages among the 3 diabetes groups (prediabetes, diabetes, neither).

RESULTS

Compared to those without diabetes, we found shorter REM duration for participants with diabetes (-6.7 min, 95%CI -13.2, -0.1) and prediabetes (-5.9 min, 95%CI -10.5, -1.3), even after adjusting for age, gender, BMI, and AHI. Diabetes was also associated with lower total sleep time (-13.7 min, 95%CI -26.8, -0.6), longer slow-wave sleep (N3) duration (+7.6 min, 95%CI 0.6, 14.6) and higher N3 percentage (+2.4%, 95%CI 0.6, 4.2), compared to those without diabetes. Results were similar when restricting to AHI < 15.

CONCLUSIONS

People with diabetes and prediabetes had less REM sleep than people without either condition. People with diabetes also had more N3 sleep. These results suggest that diabetes and prediabetes are associated with differences in sleep architecture, even in the absence of moderate-severe sleep apnea.

Effects of smoking on sleep architecture and ventilatory parameters including apneas: Results of the Tab-OSA study

Background

The interaction between smoking and sleep seems appears to be bidirectional, but few studies evaluated the impact of smoking and its cessation on objective sleep parameters. In this context, this new study aimed to assess the impact of smoking and its cessation on sleep architecture and on ventilatory sleep parameters, particularly the presence of sleep apnea syndrome (apnea-hypopnea index (AHI)≥15). Methods: Patients hospitalized for polysomnographic sleep exploration were compared according to their smoking status: active smokers (AS), former smokers (FS), non-smokers (NoNi). Psychiatric and non-psychiatric co-morbidities and treatment or substance use were taken into account in the analyses.

Results

A total of 170 participants were included (N = 37 FS, 39 AS, 86 NoNi). A significant decrease in the mean nocturnal O2 saturation was observed for FS and AS compared to NoNi. No differences were found regarding AHI. Regarding sleep architecture, we observed a significant decrease in the slow wave sleep duration for AS compared to NoNi, and interestingly not between FS and NoNi.

Conclusion

This study suggests that current smokers suffer from alterations in both sleep architecture and ventilatory parameters, the later appears to persist even after smoking cessation.

Surgical treatment for obstructive sleep apnea: effect on sleep architecture

PURPOSE

Investigate the effect of surgical treatment of obstructive sleep apnea syndrome (OSA) on sleep architecture.

METHODS

Observational retrospective analysis of polysomnographic data of adults diagnosed with OSA, submitted to surgical treatment. Median (25-75th percentile) was used to present the data.

RESULTS

Data were available for 76 adults, 55 men and 21 women, with median age of 49.0 years (41.0-62.0), body mass index of 27.3 kg/m2 (25.3-29.3) and AHI of 17.4 per hour (11.3-22.9) before surgeries. Preoperatively, 93.4% of patients had an abnormal distribution of at least one of the sleep phases. After surgical treatment, we found a significant increase in median N3 sleep percent from 16.9% (8.3-22-7) to 18.9% (15.5-25.4) (p = 0.003). Postoperatively, 18.6% patients that had an abnormal preoperative N1 sleep phase distribution had a normalization of this sleep phase, as also occurred to N2, N3 and REM sleep phases in 44.0%, 23.3% and 63.6% of patients, respectively.

CONCLUSION

This study aims to show the impact of OSA treatment, not only on respiratory events but also on other polysomnographic data often underestimated. Upper airway surgeries have shown to be effective in sleep architecture improvements. There is a trend for sleep distribution normalization, with increase of time spend in profound sleep.

Modeling the Impact of Inter-Rater Disagreement on Sleep Statistics Using Deep Generative Learning

Sleep staging is the process by which an overnight polysomnographic measurement is segmented into epochs of 30 seconds, each of which is annotated as belonging to one of five discrete sleep stages. The resulting scoring is graphically depicted as a hypnogram, and several overnight sleep statistics are derived, such as total sleep time and sleep onset latency. Gold standard sleep staging as performed by human technicians is time-consuming, costly, and comes with imperfect inter-scorer agreement, which also results in inter-scorer disagreement about the overnight statistics. Deep learning algorithms have shown promise in automating sleep scoring, but struggle to model inter-scorer disagreement in sleep statistics. To that end, we introduce a novel technique using conditional generative models based on Normalizing Flows that permits the modeling of the inter-rater disagreement of overnight sleep statistics, termed U-Flow. We compare U-Flow to other automatic scoring methods on a hold-out test set of 70 subjects, each scored by six independent scorers. The proposed method achieves similar sleep staging performance in terms of accuracy and Cohen's kappa on the majority-voted hypnograms. At the same time, U-Flow outperforms the other methods in terms of modeling the inter-rater disagreement of overnight sleep statistics. The consequences of inter-rater disagreement about overnight sleep statistics may be great, and the disagreement potentially carries diagnostic and scientifically relevant information about sleep structure. U-Flow is able to model this disagreement efficiently and can support further investigations into the impact inter-rater disagreement has on sleep medicine and basic sleep research.

Clinical phenotype of obstructive sleep apnea in older adults: a hospital-based retrospective study in China

BACKGROUND

The prevalence of obstructive sleep apnea (OSA) in older people (aged over 65 years) is high. However, OSA in older populations has not received sufficient attention. This study examined the clinical phenotypic characteristics of older patients with newly diagnosed OSA.

METHODS

A total of 110 older patients (≥ 65 years) and 220 younger patients (< 65 years), matched by gender, body mass index (BMI), and apnea-hypopnea index (AHI), were enrolled in this retrospective study. Clinical manifestations, comorbidities, and polysomnographic results were compared between the two groups, and correlations between age ≥ 65 years and OSA comorbidities were explored.

RESULTS

Nocturia was more common in older patients with OSA, as with lower sleep efficiency, longer wake after sleep onset, increased stage N1 sleep, and decreased stage N3 sleep and average SpO2. The proportions of older OSA patients who had comorbid hypertension, coronary artery disease (CAD), chronic obstructive pulmonary disease, and ischemic stroke were significantly higher than those of younger patients. The incidence of tonsillar enlargement and pharyngeal narrowing was lower in older patients. Age ≥ 65 years was an independent risk factor for patients with OSA to have hypertension (OR: 1.89, 95% CI: 1.11-3.21), CAD (OR: 4.83, 95% CI: 2.29-10.21), and ischemic stroke (OR: 2.92, 95% CI: 1.02 to 8.38).

CONCLUSIONS

The presence of OSA in older adults was associated with significant abnormalities of sleep architecture, aggravated nocturnal hypoxia and increased risks of hypertension, CAD, and stroke, which can be distinguished as a unique clinical phenotype.

Obstructive sleep apnea induced bilateral tonic- clonic seizure of unknown origin: A case series of a novel association

Background

Obstructive sleep apnea is a highly prevalent disorder, characterized by recurrent events of upper airway obstruction during sleep and associated with recurrent cycles of desaturation and re-oxygenation, sympathetic hyperactivity, and intra-thoracic pressure fluctuations, resulting in fragmentation of sleep and subsequent daytime fatigue with excessive sleepiness. Obstructive sleep apnea-induced bilateral tonic-clonic seizures are unheard of. We aimed to report 3 patients with previously undiagnosed obstructive sleep apnea who presented to the emergency department with new onset bilateral tonic-clonic seizure without any evidential neurological or metabolic cause.

Methods

Patient data were obtained from medical records from the Department of Internal Medicine, IPGMER and SSKM Hospital, Kolkata, and Belle Vue Clinic, Kolkata, India.

Results

Three male patients (67, 58, and 44 years old) presented with bilateral tonic-clonic seizure disorder without any underlying cause of seizures after rigorous investigations except for moderate to severe obstructive sleep apnea on polysomnography. All 2 patients were seizure-free after being treated with levetiracetam, chronic continuous positive airway pressure therapy in 2, and only continuous positive airway pressure in the other. The patients remained seizure-free on continuous positive airway pressure, even when levetiracetam was withdrawn, suggesting obstructive sleep apnea's causality in their new-onset acute seizures.

Conclusion

Although further investigation is required to clarify this association, underlying obstructive sleep apnea should be ruled out in patients with a first-ever bilateral tonic-clonic seizure. Whether or not continuous positive airway pressure alone could effectively treat hypoxia and deranged cortical excitability, which may lead to seizures in cases with longstanding obstructive sleep apnea, is yet to be explored.

Altered sleep architecture in diabetes and prediabetes: findings from the Baependi Heart Study

Objective

People with diabetes are more likely to have obstructive sleep apnea, but there are few studies examining sleep architecture in people with diabetes, especially in the absence of moderate-severe sleep apnea. Therefore, we compared sleep architecture among people with diabetes, prediabetes or neither condition, whilst excluding people with moderate-severe sleep apnea.

Research design and methods

This sample is from the Baependi Heart Study, a prospective, family-based cohort of adults in Brazil. 1,074 participants underwent at-home polysomnography (PSG). Diabetes was defined as 1) FBG>125 OR 2) HbA1c>6.4 OR 3) taking diabetic medication, and prediabetes was defined as 1) [(5.7≤HbA1c≤6.4) OR (100≤FBG≤125)] AND 2) not taking diabetic medication. We excluded participants that had an apnea-hypopnea index (AHI)>30 from these analyses to reduce confounding due to severe sleep apnea. We compared sleep stages among the 3 groups.

Results

Compared to those without diabetes, we found shorter REM duration for participants with diabetes (-6.7min, 95%CI -13.2, -0.1) or prediabetes (-5.9min, 95%CI -10.5, -1.3), even after adjusting for age, gender, BMI, and AHI. Diabetes was also associated with lower total sleep time (-13.7min, 95%CI -26.8, -0.6), longer slow-wave sleep (N3) duration (+7.6min, 95%CI 0.6, 14.6) and higher N3 percentage (+2.4%, 95%CI 0.6, 4.2), compared to those without diabetes.

Conclusions

People with diabetes and prediabetes had less REM sleep after taking into account potential confounders, including AHI. People with diabetes also had more N3 sleep. These results suggest that diabetes is associated with different sleep architecture, even in the absence of moderate-severe sleep apnea.

The association between sleep architecture, quality of life, and hypertension in patients with obstructive sleep apnea

OBJECTIVE

The aim of this study was to investigate the association between hypertension and overnight polysomnography measures of sleep duration, sleep architecture, and quality of life (QoL) in patients with obstructive sleep apnea (OSA).

METHODS

Participants were patients suspected of having OSA with or without hypertension. All patients underwent overnight polysomnography and completed the Epworth Sleepiness Scale (ESS), Self-Rating Anxiety Scale, Self-Rating Depression Scale, and 12-item Short-Form Health Survey.

RESULTS

Of 128 patients (mean age 46.2 ± 12.5 years), 53% had hypertension. The average total sleep duration was 344 min (standard deviation 90) or 5.7 h and sleep efficiency was < 70%. There was no significant difference between patients with OSA with/without hypertension in total sleep duration, sleep architecture, anxiety, depression, ESS scores, or QoL. In patients with OSA, nocturnal minimum oxygen saturation was significantly negatively correlated with bodily pain and physical component summary (PCS) scores; mean nocturnal saturation was negatively correlated with bodily pain and social function; anxiety showed a significant negative correlation with role emotional; and depression was significantly negatively correlated with physical function, role physical, general health, role emotional, PCS, and mental component summary (MCS) scores. In the group with OSA and hypertension, N3 duration was negatively correlated with social function, mental health, and MCS scores. Anxiety was significantly negatively correlated with physical function, role physical, vitality, mental health, role emotional, PCS, and MCS scores. Depression was significantly negatively correlated with physical function, role physical, vitality, mental health, role emotional, PCS, and MCS scores. In patients with mild, moderate, and severe OSA, QoL was associated with depression. In mild OSA, PCS was correlated with ESS and anxiety. In moderate OSA, MCS was correlated with apnea-hypopnea index scores. In severe OSA, MCS and PCS were correlated with anxiety.

CONCLUSIONS

There were no significant associations between the presence of hypertension and total sleep duration, sleep architecture, or QoL in patients with OSA. However, hypertension may affect the influencing factors of QoL in patients with OSA. Further cohort studies are needed to confirm these findings.

Different sleep pattern in over-weight/obese women with polycystic ovary syndrome

Context

Sleep duration and sleep quality have important health implications although our knowledge of objectively measured sleep variables in women with Polycystic Ovary Syndrome (PCOS) is limited.

Objective

To compare sleep variables assessed by actigraphy in over-weight/obese women with PCOS and controls, and to assess sleep variables after behavioral modification intervention in comparison with minimal intervention in a randomized trial.

Design

Randomized controlled trial, and a control group.

Setting

Outpatient gynecological clinic at a university hospital in Sweden.

Participants

39 women fulfilling all Rotterdam PCOS criteria, randomized to behavioral modification intervention or minimal intervention and 21 controls with no other metabolic disease, all aged 18-40 years with a BMI ≥ 27 kg/m2.

Intervention

A four-month behavioral modification intervention including weekly group meetings focusing on behavioral and healthy lifestyle aspects. Minimal intervention reflecting standard care.

Main outcome measure

Sleep durations and sleep efficiency assessed by actigraphy.

Results

Compared to the control group, women with PCOS had significantly shorter time in bed (501 vs 548 min, p= 0.049), sleep time over 24 hours (448 vs 567 min, p=0.005) and sleep time at night (434 vs 511 min, p=0.002), poorer sleep efficiency (87 vs 93%, p<0.001), and longer wakefulness after sleep onset (64 vs 38 min, p<0.001). However, total sleep time at night for women with PCOS (7.2hrs) was within the normal range. Following behavioral modification intervention, the reduction from baseline in sleep over 24 hours and in the daytime sleep were significant compared to the minimal intervention group (78 min, p=0.009 and 43 min, p=0.003 respectively).

Conclusions

We found over-weight/obese women with PCOS to have normal sleep duration, but worse sleep efficiency than controls. Behavioral modification intervention seems to reduce the amount of daytime sleep, suggesting improved sleep behavior.

Clinical trials registration

https://doi.org/10.1186/ISRCTN48947168, identifier ISRCTN48947168.

Oropharyngeal Rehabilitation for Patients With Moderate to Severe Obstructive Sleep Apnea After Transoral Robotic Surgery

OBJECTIVE

To determine whether combined transoral robotic surgery and postoperative oropharyngeal rehabilitation are effective for reducing the severity of obstructive sleep apnea.

STUDY DESIGN

A quasi-experimental study enrolled participants without blinding between May 2019 and April 2021.

SETTING

Single-center study at National Cheng Kung University Hospital.

METHODS

Patients with moderate to severe obstructive sleep apnea who were otherwise healthy were recruited from the ear, nose, and throat department at National Cheng Kung University Hospital. The group undergoing transoral robotic surgery with oropharyngeal rehabilitation (n = 18) received a 12-week intervention consisting of home-based rehabilitation exercises following surgery; the transoral robotic surgery group (n = 17) received surgery only; and the control group (n = 15) received conservative treatment, such as continuous positive airway pressure therapy or other oral appliance therapy. Polysomnography data and tongue muscle performance were measured before and after the interventions.

RESULTS

The group that underwent transoral robotic surgery with oropharyngeal rehabilitation exhibited significantly improved tongue protrusion strength as compared with the transoral robotic surgery-only group, as well as significantly improved apnea-hypopnea index in the supine position vs the control group.

CONCLUSION

In this study, we demonstrated the synergistic effects of transoral robotic surgery and postoperative oropharyngeal rehabilitation for adult patients with obstructive sleep apnea. Objective records should be used to monitor home-based rehabilitation exercises and examine the lasting synergistic effects.

Impact of Sleep Fragmentation on Cognition and Fatigue

Sleep continuity and efficacy are essential for optimal cognitive functions. How sleep fragmentation (SF) impairs cognitive functioning, and especially cognitive fatigue (CF), remains elusive. We investigated the impact of induced SF on CF through the TloadDback task, measuring interindividual variability in working memory capacity. Sixteen participants underwent an adaptation polysomnography night and three consecutive nights, once in a SF condition induced by non-awakening auditory stimulations, once under restorative sleep (RS) condition, counterbalanced within-subject. In both conditions, participants were administered memory, vigilance, inhibition and verbal fluency testing, and for CF the TloadDback, as well as sleep questionnaires and fatigue and sleepiness visual analog scales were administered. Subjective fatigue increased and sleep architecture was altered after SF (reduced sleep efficiency, percentage of N3 and REM, number of NREM and REM phases) despite similar total sleep time. At the behavioral level, only inhibition deteriorated after SF, and CF similarly evolved in RS and SF conditions. In line with prior research, we show that SF disrupts sleep architecture and exerts a deleterious impact on subjective fatigue and inhibition. However, young healthy participants appear able to compensate for CF induced by three consecutive SF nights. Further studies should investigate SF effects in extended and/or pathological disruption settings.

Laryngopharyngeal Reflux in Sleep-Disordered Breathing Patients

INTRODUCTION

Our study aims to evaluate the distribution of laryngopharyngeal reflux (LPR) in patients with sleep-disordered breathing (SDB) via the Reflux Symptom Index (RSI) and to describe the sleep architecture in SDB patients with and without LPR.

MATERIALS AND METHODS

A cross-sectional, descriptive study was conducted. Patients with SDB were identified via the Epworth Sleepiness Scale (ESS) and STOP-BANG questionnaire; they were then screened with the RSI and physical examination for LPR. PSG was performed to evaluate obstructive sleep apnea (OSA).

RESULTS

Of 45 patients, 15 were scored as having LPR via the RSI. Utilizing the Respiratory Disturbance Index (RDI), patients were further classified into four groups: 9 non-LPR with non-OSA SDB, 21 non-LPR with OSA, 4 LPR with non-OSA SDB, and 11 LPR with OSA. The prevalence of LPR was 30.8% in the non-OSA SDB group and 34.4% in the OSA group. All SDB parameters in both groups were similar. SDB patients with high body mass index tended to have LPR and/or OSA. Average ESS scores in the four groups suggested excessive daytime sleepiness, and patients with LPR had higher ESS scores. Regardless of LPR status, SDB patients had a lower percentage of REM sleep and a higher percentage of light sleep.

CONCLUSIONS

The incidence of LPR in OSA patients was similar in non-OSA SDB patients. REM sleep percentage decreased in the four groups, with the non-OSA SDB group having the lowest percentage of REM sleep; light sleep percentage increased in the four groups, with the OSA group having the highest percentage of light sleep.

Dynamic models of obstructive sleep apnea provide robust prediction of respiratory event timing and a statistical framework for phenotype exploration

Obstructive sleep apnea (OSA), in which breathing is reduced or ceased during sleep, affects at least 10% of the population and is associated with numerous comorbidities. Current clinical diagnostic approaches characterize severity and treatment eligibility using the average respiratory event rate over total sleep time (apnea-hypopnea index). This approach, however, does not characterize the time-varying and dynamic properties of respiratory events that can change as a function of body position, sleep stage, and previous respiratory event activity. Here, we develop a statistical model framework based on point process theory that characterizes the relative influences of all these factors on the moment-to-moment rate of event occurrence. Our results provide new insights into the temporal dynamics of respiratory events, suggesting that most adults have a characteristic event pattern that involves a period of normal breathing followed by a period of increased probability of respiratory event occurrence, while significant differences in event patterns are observed among gender, age, and race/ethnicity groups. Statistical goodness-of-fit analysis suggests consistent and substantial improvements in our ability to capture the timing of individual respiratory events using our modeling framework. Overall, we demonstrate a more statistically robust approach to characterizing sleep disordered breathing that can also serve as a basis for identifying future patient-specific respiratory phenotypes, providing an improved pathway towards developing individualized treatments.

Daytime polysomnography to perform titration for upper airway stimulation in patients with obstructive sleep apnea

PURPOSE

Upper airway stimulation (UAS) is an innovative treatment for patients with obstructive sleep apnea (OSA). UAS titrations are performed 3 months after activation of the device to optimize its effectiveness. In general, these titrations are performed during an in-laboratory overnight polysomnography (PSG). However, overnight titrations are expensive and can be logistically challenging because they are labor-intensive which causes shortage of sleep technicians available for night shifts. In addition, recently, overnight PSGs were postponed and canceled due to the COVID-19 pandemic. We aimed to assess the feasibility of a daytime PSG to perform titration of UAS therapy as an alternative for a conventional overnight PSG.

METHODS

We performed a prospective single-center observational cohort study. Patients were included when planned for UAS titration; this was approximately 6 months after UAS activation. Data on sleep architecture, patient experience, and respiratory outcomes were collected to evaluate the feasibility. An overnight follow-up PSG 12 months after implantation was used to compare sleep architecture and therapy response.

RESULTS

Of 23 patients, four were excluded from analysis because of technical issues during PSG. Even though patients slept significantly shorter during the daytime PSG, this was enough time to complete the titration successfully with 30-min sleep in final therapeutic settings in 84% of the patients. Patients (94%) had a positive experience with the daytime titration. Respiratory outcomes were significantly reduced during titration and were maintained at the 12-month follow-up.

CONCLUSION

Daytime titrations are a valuable alternative for conventional overnight titrations. Our findings suggest the implementation of daytime titrations as standard of care. This will contribute to easier logistics and better work circumstances for sleep technicians without jeopardizing titration quality.

Risk of current suicidal ideations associated with lifelong anhedonia and recent change of anhedonia in individuals with insomnia: A cross-sectional study

BACKGROUND

Individuals with insomnia are a subpopulation at high-risk of suicide. However, despite the elements in favour of an implication of anhedonia in the occurrence of current suicidal ideations (SI), no study has investigated the role played by this affective symptom in the occurrence of current SI in individuals with insomnia. The aim of this study was to investigate the risk of current SI associated with lifelong anhedonia and recent change of anhedonia in individuals with insomnia.

METHOD

Demographic and polysomnographic data from 493 individuals with insomnia selected retrospectively from the clinical database of the Erasme Hospital Sleep Laboratory were analysed. Current SI were considered present if the score in item 9 of the Beck Depression Inventory (BDI-II) was ≥1 and/or if they were highlighted during the systematic psychiatric assessment conducted on admission to the Sleep Laboratory. Logistic regression analyses were used to determine the risk of current SI associated with anhedonia in individuals with insomnia.

RESULTS

The prevalence of current SI was 21.5% in our sample of individuals with insomnia. After adjusting for major confounding factors, multivariate logistic regression analyses demonstrated that unlike lifelong anhedonia, only recent change of anhedonia was a risk factor for current SI in individuals with insomnia.

CONCLUSION

In this study, we demonstrated that in individuals with insomnia, recent change of anhedonia is a risk factor for current SI, which seems to justify more systematic research and adequate therapeutic management of this condition to allow better prevention in this particular subpopulation at high-risk of suicide.

The effects of adeno/tonsillectomy on cardiopulmonary function based on echocardiography indices in children with primary snoring and mild obstructive sleep apnea

BACKGROUND

The goal of this study was to evaluate the effects of adenotonsillectomy on heart function based on echocardiography indices in children with primary snoring (PS) and mild obstructive sleep apnea due to adenotonsillar hypertrophy (ATH).

METHODS

55 children (aged 7 to 11 years old) with PS and ATH who were a candidate for adenotonsillectomy from August 2018 to June 2019 evaluated. A history of Upper Respiratory Tract Obstruction was obtained, clinical examination was performed and the cases suspicious for moderate to severe degrees of Obstructive Sleep Apnea Syndrome were excluded. Echocardiography was performed one week before and 3-6 months after surgery. All data were analyzed by SPSS version 19 and P-value<0.05 was considered significant.

RESULTS

From 55 enrolled cases, 42 [30 boys (71.5%) and 12 girls (28.5%)] completed the study course. Tricuspid Annular Plane Systolic Excursion (TAPSE), Ejection Fraction (EF), Right Ventricular Peak Systolic Myocardial Velocity (RVSM), Right Ventricular Fractional Area Change (RVFAC) were increased significantly and Isovolumic Contraction Time (IVCT) index was decreased significantly after surgery (P-value<0.05). The difference of indices between the two sexes was not significant after surgery (P-value>0.05).

CONCLUSION

Adenotonsillectomy can improve cardiac function indices in patients with PS due to ATH especially in terms of right ventricle (RV) function and reduction in pulmonary artery pressure. So, although "subclinical", it is better to be considered PS not just as annoying noise for roommates before significant clinical cardiac problems happen.

The independent effects of sleep deprivation and sleep fragmentation on processing of emotional information

Disrupted sleep through sleep deprivation or sleep fragmentation has previously been shown to impair cognitive processing. Nevertheless, limited studies have examined the impact of disrupted sleep on the processing of emotional information. The current study aimed to use an experimental approach to generate sleep disruption and examine whether SD and SF in otherwise healthy individuals would impair emotional facial processing. Thirty-five healthy individuals participated in three-day/two-night laboratory study which consisted of two consecutive overnight polysomnograms and cognitive testing during the day. The first night was an adaptation night of normal sleep while the second was an experimental night where participants underwent either a night of 1) normal sleep, 2) no sleep (SD) or 3) fragmented sleep (SF). The emotional Go/No-Go task was completed in the morning following each night. Data from 33 participants (14 females, mean age = 24.6 years) were included in the final analysis. Following a night of SD or SF, participants performed significantly poorer with emotional (fearful and happy) targets, while no significant changes occurred after a night of normal sleep. Further, sleep deprived individuals experienced additional impairments with notably poorer performance with neutral targets and slower reaction time for all targets, suggesting an overall slowing of cognitive processing speed. These findings suggest that facial recognition in socio-emotional contexts may be impaired in individuals who experience disrupted sleep.

A Study of Factors Causing Sleep State Misperception in Patients with Depression

PURPOSE

Sleep state misperception, which is the discrepancy between subjective and objective sleep, is often observed in patients with depression. This phenomenon may delay the remission of depression. Previous studies have focused on the total sleep time (TST) misperception, with many of these studies using actigraphy. Thus, our study investigated depressed patients with the exploratory aim of clarifying factors associated with the sleep state misperception including the wake after sleep onset (WASO) misperception, with their objective sleep additionally evaluated by polysomnography (PSG).

PATIENTS AND METHODS

We conducted a cross-sectional study. Before undergoing overnight PSG monitoring, 40 patients with depression completed questionnaires that included the Beck Depression Inventory (BDI), Epworth sleepiness scale, Temperament and Character Inventory, and the Pittsburgh sleep quality index. Patients were also asked to estimate their subjective sleep duration after they woke up in the morning. Based on this data, we calculated the misperception using the following formula: subjective sleep duration minus objective sleep duration. We compared each factor between negative and positive misperception groups and the multiple regression analysis was performed for TST and WASO misperception, respectively.

RESULTS

Although sleep architectures, age, severity of depression and obstructive sleep apnea (OSA) exhibited differences in underestimating or overestimating the WASO, only sex differences were associated with underestimating or overestimating their total sleep time (TST). Moreover, BDI, the severity of OSA, sleep architectures (N1% and N2%), and benzodiazepine (BZD) use were significantly correlated with WASO misperception, whereas only OSA severity was significantly correlated with TST misperception. A subsequent multiple regression analysis demonstrated the BDI was independently correlated with the WASO misperception (β=0.341, p=0.049).

CONCLUSION

In clinical practice, interventions especially for OSA, and the reduction of depressive symptoms are an important method for improving patient sleep perception. Moreover, current results suggest that BZD prescriptions should be avoided as well.

Towards Validating the Effectiveness of Obstructive Sleep Apnea Classification from Electronic Health Records Using Machine Learning

Obstructive sleep apnea (OSA) is a common, chronic, sleep-related breathing disorder characterized by partial or complete airway obstruction in sleep. The gold standard diagnosis method is polysomnography, which estimates disease severity through the Apnea-Hypopnea Index (AHI). However, this is expensive and not widely accessible to the public. For effective screening, this work implements machine learning algorithms for classification of OSA. The model is trained with routinely acquired clinical data of 1479 records from the Wisconsin Sleep Cohort dataset. Extracted features from the electronic health records include patient demographics, laboratory blood reports, physical measurements, habitual sleep history, comorbidities, and general health questionnaire scores. For distinguishing between OSA and non-OSA patients, feature selection methods reveal the primary important predictors as waist-to-height ratio, waist circumference, neck circumference, body-mass index, lipid accumulation product, excessive daytime sleepiness, daily snoring frequency and snoring volume. Optimal hyperparameters were selected using a hybrid tuning method consisting of Bayesian Optimization and Genetic Algorithms through a five-fold cross-validation strategy. Support vector machines achieved the highest evaluation scores with accuracy: 68.06%, sensitivity: 88.76%, specificity: 40.74%, F1-score: 75.96%, PPV: 66.36% and NPV: 73.33%. We conclude that routine clinical data can be useful in prioritization of patient referral for further sleep studies.

Sleep-Disordered Breathing and Cardiovascular Disease in Children and Adolescents: A Scientific Statement From the American Heart Association

Obstructive sleep apnea (OSA) is a known risk factor for cardiovascular disease in adults. It is associated with incident systemic hypertension, arrhythmia, stroke, coronary artery disease, and heart failure. OSA is common in children and adolescents, but there has been less focus on OSA as a primary risk factor for cardiovascular disease in children and adolescents. This scientific statement summarizes what is known regarding the impact of sleep‐disordered breathing and, in particular, OSA on the cardiovascular health of children and adolescents. This statement highlights what is known regarding the impact of OSA on the risk for hypertension, arrhythmia, abnormal ventricular morphology, impaired ventricular contractility, and elevated right heart pressure among children and adolescents. This scientific statement also summarizes current best practices for the diagnosis and evaluation of cardiovascular disease–related complications of OSA in children and adolescents with sleep apnea and highlights potential future research in the area of sleep‐disordered breathing and cardiovascular health during childhood and adolescence.

Association of short-term exposure to air pollution with depression in patients with sleep-related breathing disorders

Air pollution is associated with sleep-related breathing disorders; however, the effects of air pollution on depression in patients with SRBDs remain unclear. A cross-sectional study was conducted to collect polysomnographic (PSG) data and Beck Depression Inventory-IA (BDI-IA) responses from 568 subjects with SRDBs in a sleep center in 2015 to 2017. Exposure to air pollution, including particulate matter with an aerodynamic diameter of ≤10 μm (PM₁₀), particulate matter with an aerodynamic diameter of ≤2.5 μm (PM_2.5), nitrogen (NO₂), sulfur dioxide (SO₂), carbon monoxide (CO) and ozone (O₃), in 1-month averages was collected. Associations of air pollution with the respiratory disturbance index (RDI), oxygen desaturation index (ODI), arousal index (ARI), sleep architecture, and BDI-IA were examined. We observed that interquartile range (IQR) increases in 1-month PM_2.5, PM₁₀, and NO₂ levels were respectively associated with 4.1/hour (h) (95% confidence interval (CI): 1.7/h to 6.4/h), 3.7/h (95% CI: 1.4/h to 6.0/h) and 1.9/h (95% CI: 0.1/h to 3.7/h) increases in the ARI. For sleep architecture, IQR increases in 1-month PM_2.5 and CO levels were respectively associated with a 6.2% (95% CI: 6.1% to 6.3%) increase in non-rapid eye movement sleep 1 (N1) and a 2.0% (95% CI: -3.8% to -0.1%) decrease in non-rapid eye movement sleep 2 (N2). For depression, an IQR change in the 1-month CO was associated a moderate/severe depressive status according to the BDI-IA (odds ratio, OR: 2.981, p < 0.05; 95% CI: 1.032 to 8.611). Short-term exposure to air pollution increased the risk of arousal and light sleep as well as depression in patients with SRBDs. The results suggest that SRBD patients could be a population at risk for depression due to short-term exposure to air pollution.

Rapid eye movement sleep and slow wave sleep rebounded and related factors during positive airway pressure therapy

This study aimed to investigate the clinical characteristics and predictors of increased rapid eye movement (REM) sleep or slow wave sleep (SWS) in patients with obstructive sleep apnea (OSA) following positive airway pressure (PAP) therapy. The study retrospectively analyzed data from patients with OSA who underwent both diagnostic polysomnography (PSG) and pressure titration PSG at the Tangdu Hospital Sleep Medicine Center from 2011-2016. Paired diagnostic PSG and pressure titration studies from 501 patients were included. REM rebound was predicted by a higher oxygen desaturation index, lower REM proportion, higher arousal index, lower mean pulse oxygen saturation (SpO2), higher Epworth sleepiness score and younger age (adjusted R2 = 0.482). The SWS rebound was predicted by a longer total duration of apneas and hypopneas, lower N3 duration, lower SpO2 nadir, lower REM proportion in diagnostic PSG and younger age (adjusted R2 = 0.286). Patients without REM rebound or SWS rebound had a high probability of comorbidities with insomnia and mood complaints. Some parameters (subjective and objective insomnia, excessive daytime sleepiness, age and OSA severity) indicate changes in REM sleep and SWS between diagnostic and titration PSG tests. Treatment of insomnia and mood disorders in patients with OSA may helpful to improve the use PAP.

EEG Power Spectral Analysis of Abnormal Cortical Activations During REM/NREM Sleep in Obstructive Sleep Apnea

Objective: To characterize electroencephalogram (EEG) power in different frequency bands during rapid eye movement (REM) sleep and non-rapid eye movement (NREM) sleep in patients with obstructive sleep apnea (OSA). Methods: Retrospective data on 151 patients were collected and divided into three groups: primary snoring group (AHI < 5/h), mild-moderate OSA group (6 ≤ AHI < 30/h), and severe OSA group (AHI ≥ 30/h). EEG recordings in the frontal, central, and occipital regions were extracted from both REM and NREM sleep, to compute the normalized spectral power densities in the delta, theta, alpha, sigma, beta, and gamma frequency bands, using Fast Fourier Transform. Correlations between the computed EEG power and PSG parameters were analyzed. Results: In NREM sleep, elevated normalized power spectral density (PSD) in the delta band was observed in the severe OSA group compared to the other two groups. In contrast, the PSD of the other frequency bands showed a corresponding decrease in the severe OSA group. In REM sleep, similar changes were observed in the frontal region. Delta band PSD was positively correlated with Apnea Hypopnea Index (AHI) (r = 0.33), longest time of apnea, oxygen desaturation index (ODI) (r = 0.34), percent sleep time below 90% SaO₂ (T90%) (r = 0.30), Arousal Index (ArI) (r = 0.29), and negatively correlated with N3%, minimum oxygen saturation (minSaO₂). Conclusion: Our findings provide neurophysiological evidence for pathological cortical activation during REM/NREM sleep, which may be associated with the arousals and cognitive impairments in OSA. The technique of power spectral analysis could prove a potentially useful tool in complementing traditional PSG parameters in assessing disease burden to guide therapeutic decisions.

High sleep-related breathing disorders among HIV-infected patients with sleep complaints

BACKGROUND

Sleep-related breathing disorders (SRBD) not only adversely impact cardiovascular and pulmonary functions but also reduce the quality of life. This study attempted to investigate the severity and related factors of SRBD among human immunodeficiency virus (HIV)-infected people with sleep complaints.

METHODS

A cross-sectional study was conducted among HIV-infected people with Pittsburgh Sleep Quality Index (PSQI) values above 5 points. SRBDs were defined as Apnea-Hypopnea Index (AHI) over 5 events/hour by full channel home-based polysomnography (PSG). An AHI greater than 30 was categorized as moderate to severe apnea. All of the participants were asked to rate the severity of their snoring, complete a snore outcomes survey (SOS) and complete the PSQI. Multiple logistic regression analysis was conducted to examine the associated factors of severity of SRBD among HIV-infected people.

RESULTS

Of 54 male HIV-positive patients with sleep complaints, 34 subjects (62.96%) were diagnosed with SRBDs, and 29.63% were categorized as having moderate to severe SRBD. SOS score was significantly associated with HIV patients with moderate to severe SRBD (adjusted odds ratio = 0.93, 95% CI: 0.87-1.00, p = 0.045).

CONCLUSIONS

SRBDs is highly prevalent in male HIV-infected people with sleep complaints. Intensive snoring was one of the indicators associated with the occurrence of moderate to severe SRBDs among HIV-infected people. Healthcare professionals should include snoring screening in the regular course of clinical HIV care.

Relationships between objective sleep parameters and inflammatory biomarkers in pregnancy

We examined the relationships between sleep and inflammatory biomarkers during late pregnancy. Seventy-four women underwent an overnight sleep assessment by polysomnography. Blood samples were collected before bedtime and again within 1 h upon awakening to measure C-reactive protein (CRP), interleukin (IL)-6, and IL-6 soluble receptor. Sleep parameters included variables characterizing sleep architecture and sleep continuity. The participants were 32.2 (SD = 4.1) years old, and the average gestational age was 32.8 (3.5) weeks. Controlling for covariates, evening CRP was negatively associated with N3 sleep (β = -0.30, P = 0.010). N3 sleep was also negatively associated with morning CRP (β = -0.26, P = 0.036), with a higher percentage of N3 sleep associated with a lower level of morning CRP. Contrarily, there was a tendency for a positive association between stage N2 sleep and morning CRP (β = 0.23, P = 0.065). Stage N1 sleep was associated with morning IL-6 (β = 0.28, P = 0.021), with a higher percentage of N1 sleep associated with a higher morning IL-6. No significant associations were found between morning inflammatory biomarkers and sleep continuity parameters. In conclusion, increased light sleep was associated with increased inflammatory biomarkers, whereas more deep sleep was associated with decreased inflammatory biomarkers. These findings further support the interactions between sleep and the immune system during late pregnancy.

Does Nasal Obstruction Induce Obstructive Sleep Apnea in Healthy Women?

PURPOSE

Obstructive sleep apnea (OSA) is less prevalent among women and is associated with different symptoms and consequences to OSA in men. The reasons for these differences are unknown and difficult to tease apart in clinical populations. If OSA could be temporarily induced in healthy men and women, the causes of some of these differences could be investigated. Nasal blocking has been used to induce OSA in healthy men but its effect in women has not been reported.

PATIENTS AND METHODS

A total of 14 healthy individuals (10 women) underwent in-laboratory diagnostic sleep studies on two occasions separated by a week. On one occasion, the nasal passages were blocked, whereas on the other occasion, participants slept naturally. In both conditions, a full-face mask was used to monitor respiratory events. Participants' self-reported sleepiness, mood and performance on a motor learning task were assessed in the evening and morning of both sleep studies. Furthermore, endothelial function and self-reported sleep quality were assessed in the morning following each study.

RESULTS

Nasal blockage induced OSA in healthy young (age=22±3 years) and slim (BMI=22.2±3.2 kg/m²) women (control AHI=2.0±2.6, blocked AHI=33.1±36.7 events/hr, p=0.02). One night of OSA was associated with poorer self-reported sleep quality (p<0.001) and increased self-reported snoring (p<0.04), choking and gasping during sleep (p<0.001) but was not associated with alterations in mood, neurocognitive or endothelial function on the following morning.

CONCLUSION

Nasal blockage induces OSA in healthy, young, and normal weight women. However, whether the induced OSA is representative of naturally occurring OSA and the technique useful for future studies is unclear.