Obstructive sleep apnea

Association between sleep duration and subjective memory complaints: A large-scale cross-sectional study based on NHANES

Objective

When chatting, people often forget what they want to say, that is, they suffer from subjective memory complaints (SMCs). This research examines the Association between sleep duration and self-reported SMC in a sample representing the entire United States.

Methods

We examined data from 5567 individuals (aged 20-80) who participated in the National Health and Nutrition Examination Survey (2015-2018) to evaluate the association between sleep duration and SMC. Odds ratios (ORs) and a restricted cubic spline (RCS) curve were calculated with multiple logistic regression, and subgroup analysis was performed.

Results

Approximately 5.8 % (3 2 3) reported SMC, and most are older people (1 6 3). RCS analysis treating sleep duration as a continuous variable revealed a J-shaped curve association between sleep duration and SMC. Self-reported sleep duration was significantly linked to a 33 % elevated risk of SMC (OR, 1.33; 95 % confidence interval [CI], 1.23-1.43; P < 0.001). In the group analysis, individuals who slept more than 8 h per day had a greater association of experiencing SMC than those who slept for 6-8 h/day (OR, 1.75; 95 % CI, 1.36-2.23; P < 0.001). In the analysis of age groups, the stable association between sleep duration and SMC was observed only in the 60-80 age bracket (OR, 1.59; 95 % CI, 1.09-2.33; P < 0.001).

Conclusions

We found that people with self-report sleep duration exceeding 8 h are more likely to experience SMC, especially older adults. Improving sleep health may be an effective strategy for preventing SMC and cognitive impairment.

Obstructive Sleep Apnea Syndrome and Obesity Indicators, Circulating Blood Lipid Levels, and Adipokines Levels: A Bidirectional Two-Sample Mendelian Randomization Study

Purpose

This investigation sought to elucidate the genetic underpinnings that connect obesity indicators, circulating blood lipid levels, adipokines levels and obstructive sleep apnea syndrome (OSAS), employing a bidirectional two-sample Mendelian randomization (MR) analysis that utilizes data derived from extensive genome-wide association studies (GWAS).

Methods

We harnessed genetic datasets of OSAS available from the FinnGen consortium and summary data of four obesity indices (including neck circumference), seven blood lipid (including triglycerides) and eleven adipokines (including leptin) from the IEU OpenGWAS database. We primarily utilized inverse variance weighted (IVW), weighted median, and MR-Egger methods, alongside MR-PRESSO and Cochran's Q tests, to validate and assess the diversity and heterogeneity of our findings.

Results

After applying the Bonferroni correction, we identified significant correlations between OSAS and increased neck circumference (Odds Ratio [OR]: 3.472, 95% Confidence Interval [CI]: 1.954-6.169, P= 2.201E-05) and decreased high-density lipoprotein (HDL) cholesterol levels (OR: 0.904, 95% CI: 0.858-0.952, P= 1.251E-04). Concurrently, OSAS was linked to lower leptin levels (OR: 1.355, 95% CI: 1.069-1.718, P= 0.012) and leptin receptor levels (OR: 0.722, 95% CI: 0.530-0.996, P= 0.047). Sensitivity analyses revealed heterogeneity in HDL cholesterol and leptin indicators, but further multiplicative random effects IVW method analysis confirmed these correlations as significant (P< 0.05) without notable heterogeneity or horizontal pleiotropy in other instrumental variables.

Conclusion

This investigation compellingly supports the hypothesis that OSAS could be a genetic predisposition for elevated neck circumference, dyslipidemia, and adipokine imbalance. These findings unveil potential genetic interactions between OSAS and metabolic syndrome, providing new pathways for research in this domain. Future investigations should aim to delineate the specific biological pathways by which OSAS impacts metabolic syndrome. Understanding these mechanisms is critical for developing targeted prevention and therapeutic strategies.

Periodic limb movements in patients with suspected obstructive sleep apnea without comorbid conditions

Background

Periodic limb movement disorder (PLMD) and obstructive sleep apnea (OSA) are overlapping clinical syndromes with common risk factors. However, current literature has failed to establish a clear pathophysiological link between them. Thus, little is known about periodic limb movements (PLM) in otherwise healthy patients with suspected OSA.

Methods

We performed a retrospective analysis of 112 patients (age: 44.5 ± 12.0 years, 14.3% female) with suspected OSA who underwent full night polysomnography for the first time. Patients with chronic diseases of any kind, recent infections, malignancies, or daily or regular use of any type of medication were excluded. Group comparisons were made based on the severity of OSA (using the apnea hypopnea index, AHI) or the periodic limb movement index (PLMI).

Results

Both, PLMI and the total number of periodic limb movements during sleep (PLMS), showed a significant increase in patients with severe OSA. In addition, AHI and apnea index (AI) were significantly higher in patients with PLMI >15/h, with a similar trend for hypopnea index (HI) (p < 0.001, p < 0.001, and p > 0.05, respectively). PLMI was significantly positive correlated with AHI, AI, and HI (r = 0.392, p < 0.001; r = 0.361, p < 0.001; and r = 0.212, p < 0.05, respectively). Patients with PLMI >15/h were significantly older (p < 0.001). There was no significant association between body mass index (BMI) and PLMI >15/h.

Conclusion

We found a significant association between the severity of OSA and PLM in our study population with suspected OSA but without other comorbidities. PLMI and PLMS were significantly increased in patients with severe OSA. Future prospective studies with larger collectives should verify the presented results and should include mechanistic aspects in their evaluation.

[Sleep disorders in patients with chronic tinnitus]

Tinnitus has a lifetime prevalence of 25% in Germany. A common comorbidity in chronic cases are sleep disorders. The aims of this study were to detect sleep disorders and to identify possible associations with tinnitus parameters.Fifty patients with chronic tinnitus were recruited. The patients underwent audiometry, polysomnography, and completed standardised questionnaires on tinnitus and sleep behaviour.Data were available in 30 men and 9 women (age 50.2 ± 11 y, BMI 28.8 ± 4.4 kg/m²). The median duration of tinnitus was 36 (9; 120) months with a severity score of 2.00 (1.00; 3.00). The mean Tinnitus Questionnaire (TF) score was 43.6 ± 17.1, the Epworth Sleepiness Scale (ESS) score was 8.41 ± 4.27, the Pittsburgh Sleep Quality Index (PSQI) score was 9.21 ± 4.32, and the Screening Scale for Chronic Stress (SSCS) score was 58.13 ± 9.58.Sleep diagnoses included 18 cases of insomnia, 4 cases of RLS, and 11 cases of OSA. Patients with sleep comorbidities showed higher tinnitus severity, PSQI scores, and body weight compared to those without sleep disorders.Worse sleep quality was associated with higher tinnitus severity (p=0.038) and more disruptive tinnitus (p=0.03). Patients with subjectively highly disruptive tinnitus reported higher chronic stress scores. Tinnitus duration was correlated with OSA-severity (p=0.026).More than two-thirds of tinnitus patients showed sleep disorders as comorbidity. A sleep screening appears useful in cases of increased tinnitus severity. Whether CPAP therapy is helpful in reducing tinnitus symptoms could not be conclusively determined but deserves further attention.

The prevalence of obstructive sleep apnea syndrome after COVID-19 infection

Obstructive sleep apnea is a well-known risk factor regarding the severity of COVID-19 infection. However, to date, relatively little research performed on the prevalence of obstructive sleep apnea in COVID-19 survivors. The purpose of this study was to investigate the risk of obstructive sleep apnea after COVID-19 infection. This study was based on data collected from the US Collaborative Network in TriNetX. From January 1, 2020 to June 30, 2022, participants who underwent the SARS-CoV-2 test were included in the study. Based on their positive or negative results of the COVID-19 test results (the polymerase chain reaction [PCR] test), we divided the study population into two groups. The duration of follow-up began when the PCR test was administered and continued for 12 months. Hazard ratios (HRs) and 95% confidence intervals (CIs) for newly recorded COVID-19 positive subjects for obstructive sleep apnea were calculated using the Cox proportional hazards model and compared to those without COVID-19 infection. Subgroup analyses were performed for the age, sex, and race, groups. The COVID-19 group was associated with an increased risk of obstructive sleep apnea, at both 3 months of follow-up (HR: 1.51, 95% CI: 1.48-1.54), and 1 year of follow-up (HR: 1.57, 95% CI: 1.55-1.60). Kaplan-Meier curves regarding the risk of obstructive sleep apnea revealed a significant difference of probability between the two cohorts in the follow-up periods of 3 months and 1 year (Log-Rank test, p < 0.001). The risks of obstructive sleep apnea among COVID-19 patients were significant in the less than 65 year of age group (HR: 1.50, 95% CI: 1.47-1.52), as well as in the group older than or equal to 65 years (HR:1.69, 95% CI: 1.64-1.73). Furthermore, the risks of obstructive sleep apnea were evident in both the male and female COVID-19 groups. Compared to the control group, the risks of obstructive sleep apnea in the COVID-19 participants increased in the subgroups of White (HR: 1.62, 95% CI: 1.59-1.64), Blacks/African Americans (HR: 1.50, 95% CI: 1.45-1.55), Asian (HR: 1.46, 95% CI: 1.32-1.62) and American Indian/Alaska Native (HR: 1.36, 95% CI: 1.07-1.74). In conclusion, the incidence of new diagnosis obstructive sleep apnea could be substantially higher after COVID-19 infection than non-COVID-19 comparison group. Physicians should evaluate obstructive sleep apnea in patients after COVID-19 infection to help prevent future long-term adverse effects from occurring in the future, including cardiovascular and neurovascular disease.

A Review of Novel Oximetry Parameters for the Prediction of Cardiovascular Disease in Obstructive Sleep Apnoea

Obstructive sleep apnoea (OSA) is a sleep disorder with repetitive collapse of the upper airway during sleep, which leads to intermittent hypoxic events overnight, adverse neurocognitive, metabolic complications, and ultimately an increased risk of cardiovascular disease (CVD). The standard diagnostic parameter for OSA, apnoea-hypopnoea index (AHI), is inadequate to predict CVD morbidity and mortality, because it focuses only on the frequency of apnoea and hypopnoea events, and fails to reveal other physiological information for the prediction of CVD events. Novel parameters have been introduced to compensate for the deficiencies of AHI. However, the calculation methods and criteria for these parameters are unclear, hindering their use in cross-study analysis and studies. This review aims to discuss novel parameters for predicting CVD events from oximetry signals and to summarise the corresponding computational methods.

Drug-induced sleep endoscopy-continuous positive airway pressure (DISE-CPAP), a newer modality to choose the right candidates for CPAP

BACKGROUND

Continuous positive airway pressure (CPAP) therapy is recommended for moderate-to-severe obstructive sleep apnea (OSA). We aimed to investigate whether or not combining drug-induced sleep endoscopy (DISE) with CPAP titration may inform more appropriate pressure settings.

MATERIALS AND METHODS

A sleep CPAP titration study and DISE-CPAP treatment were performed on consecutive subjects with moderate-to-severe OSA under controlled sedation using bispectral monitoring. Video recordings of dynamic changes in UA with CPAP pressure ranges of 5 to 25 cm were assessed in accordance with the VOTE classification. The 95th percentile (95th PC) pressure of the CPAP titration trial was compared to optimal pressure for alleviating UA blockage.

RESULTS

We included 30 subjects (mean age 37.5, 17% women). All showed UA collapse at more than one level, with more than 80% of them collapsing completely at the levels of the velum and oropharynx. At the velum, 90% of subjects experienced improvement with CPAP. At the oropharynx, 75% of subjects experienced improvement with CPAP. The mean pressure and standard deviation (SD) of the 95th PC of the CPAP titration was 14.3 (3.5) cmH2O, while the pressure required to partially or fully open the airway (best possible pressure) was 16.1 (3.9) cmH2O; mean (SD) difference, 1.9 (2.2); P ≤ 0.001. The limits of agreement between the CPAP 95th pressure and the ideal pressure were - 6.32 to + 2.52.

CONCLUSIONS

The palate and lateral pharynx were more affected by CPAP than the hypopharynx. Most of the time, the mean 95th PC CPAP titration pressure was lower than the mean optimal pressure needed to alleviate the collapse.

Anatomic Features of the Nasal and Pharyngeal Region Do Not Influence PAP Therapy Response

The objective of this study was to investigate to which extent anatomic features of the nasal and pharyngeal region contribute to the severity of obstructive sleep apnea (OSA) and positive airway pressure (PAP) therapy response. Therefore, 93 patients (mean age 57.5 ± 13.0 years, mean body mass index 32.2 ± 5.80 kg/m2, 75 males, 18 females) diagnosed with OSA who subsequently started PAP therapy were randomly selected from the databank of a sleep laboratory of a tertiary university medical center. Patients were subdivided based on nasal anatomy (septal deviation, turbinate hyperplasia, their combination, or none of the above), pharyngeal anatomy (webbing, tonsillar hyperplasia, their combination, or none of the above), and (as a separate group) tongue base anatomy (no tongue base hyperplasia or tongue base hyperplasia). Then, polysomnographic data (e.g., arousal index, ARI; respiratory disturbance index, RDI; apnea index, AI; hypopnea index, HI; and oxygen desaturation index, ODI) of diagnostic polysomnography (PSG) and PAP therapy control PSG were collected, grouped, and evaluated. Septal deviation, turbinate hyperplasia, or their combination did not significantly affect the assessed PSG parameters or the response to PAP therapy compared with patients without nasal obstruction (p > 0.05 for all parameters). Accordingly, most PSG parameters and the response to PAP therapy were not significantly affected by webbing, tonsil hyperplasia, or their combination compared with patients without pharyngeal obstruction (p > 0.05 for RDI, AI, HI, and ODI, respectively). However, in the pharyngeal anatomy group, ARI was significantly higher in patients with tonsil hyperplasia (p = 0.018). Further, patients with tongue base hyperplasia showed a significantly higher HI in the diagnostic PSG (p = 0.025) compared with patients with normal tongue base anatomy, but tongue base anatomy did not significantly affect the response to PAP therapy (p > 0.05 for all parameters). The influence of anatomic features of the nasal and pharyngeal region on PAP therapy response appears to be small, and generalizability of these results requires further studies.

Obstructive sleep apnea and epilepsy: understanding the pathophysiology of the comorbidity

Obstructive sleep apnea (OSA) is a sleep disorder of significant health concern with a high prevalence in the general population. It has been found to exhibit a high incidence of comorbidity with epilepsy, the exact underlying pathophysiology of which still remains poorly understood. OSA is characterized by apnea/hypopnea spells and arousals, leading to intermittent hypoxemia and sleep deprivation. Both sleep deprivation and hypoxemia adversely affect the cortical excitability and favor epileptogenesis and worsening of pre-existing epilepsy, if any. In patients with OSA, deprivation of rapid eye movement sleep (REMS) phase (known for its strong antiepileptic influence) is relatively more than that non rapid eye movement sleep phase leading to postulation of REMS deprivation as a significant factor in the development of epilepsy as a comorbidity in patients with OSA. Furthermore, OSA and epilepsy both have shown to exercise a bidirectional influence on one another and are also likely to exacerbate each other through a positive feedback mechanism. This is especially based on the reports of improved control of epilepsy upon treatment of comorbid OSA. This brief paper attempts to present an underlying pathophysiological basis of the comorbidity of OSA and epilepsy based upon sleep deprivation and hypoxemia that are characteristic features observed in patients with OSA.

Reflection-Boosted Wearable Ring-Type Pulse Oximeters for SpO2 Measurement with High Sensitivity and Low Power Consumption

In this study, we demonstrated a Monte Carlo simulation to model a finger structure and to calculate the intensity of photons passing through tissues, in order to determine optimal angular separation between a photodetector (PD) and a light-emitting diode (LED), to detect SpO₂. Furthermore, our model was used to suggest a mirror-coated ring-type pulse oximeter to improve the sensitivity by up to 80% and improve power consumption by up to 65% compared to the mirror-uncoated structure. A ring-type pulse oximeter (RPO) is widely used to detect photoplethysmography (PPG) signals for SpO₂ measurement during sleep and health-status monitoring. Device sensitivity and the power consumption of an RPO, which are key performance indicators, vary greatly with the geometrical arrangement of PD and LED within the inner surface of an RPO. We propose a reflection-boosted design of an RPO to achieve both high sensitivity and low power consumption, and determine an optimal configuration of a PD and LED by performing a 3D Monte Carlo simulation and confirming its agreement with experimental measurement. In order to confirm the reflection-boosted performance in terms of signal-to-noise ratio, R ratio, and perfusion index (PI), RPOs were fabricated with and without a highly reflective coating, and then used for SpO₂ measurement from eight participants. Our simulation allows the numerical calculation of the intensity of photon passing and scattering through finger tissues. The reflection-boosted RPO enables reliable measurement with high sensitivity, resulting in less power consumption for the LED and longer device usage than conventional RPOs without any reflective coating, in order to maintain the same level of SNR and PI. Compared to the non-reflective reference RPO, the reflection-boosted RPO design greatly enhanced both detected light intensity (67% in dc and 322% in ac signals at a wavelength λ₁ = 660 nm, and also 81% and 375% at λ₂ = 940 nm, respectively) and PI (23.3% at λ₁ and 25.5% at λ₂). Thus, the reflection-boosted design not only enhanced measurement reliability but also significantly improved power consumption, i.e., by requiring only 36% and 30% power to drive the LED sources with λ₁ and λ₂, respectively, to produce the device performance of a non-reflective RPO reference. It is expected that our proposed RPO provides long-term monitoring capability with low power consumption and an enhanced PI for SpO₂ measurement.

Functional and Anatomical Outcomes of Anti-Vascular Endothelial Growth Factor Treatment for Exudative Age-Related Macular Degeneration with or without Obstructive Sleep Apnea

(1) To investigate the functional and anatomical outcomes of anti-vascular endothelial growth factor (anti-VEGF) treatment in patients with exudative age-related macular degeneration (AMD) with or without obstructive sleep apnea (OSA); (2) In total, 65 patients with AMD with or without OSA who received three consecutive doses of intravitreal anti-VEGF injections were enrolled. The primary outcomes-best-corrected visual acuity (BCVA) and central macular thickness (CMT)-were assessed at 1 and 3 months. Moreover, morphological changes observed through optical coherence tomography were analyzed; (3) In total, 15 of the 65 patients had OSA and were included in the OSA group; the remaining 50 patients were included in the non-OSA (control) group. At 1 and 3 months after treatment, BCVA and CMT had improved but did not differ significantly between the groups. More patients in the OSA group demonstrated subretinal fluid (SRF) resorption at 3 months after treatment than in the non-OSA group (p = 0.009). Changes in other imaging biomarkers, such as intraretinal cysts, retinal pigment epithelium detachment, hyperreflective dots, and ellipsoid zone disruptions, did not differ significantly between the groups; (4) Our results suggest that the BCVA and CMT outcomes 3 months after anti-VEGF treatment are similar between patients with and without OSA. Moreover, patients with OSA may exhibit superior SRF resorption. A large-scale prospective study is mandatory to evaluate the association between SRF resorption and visual outcomes in AMD patients with OSA.

The Prevalence of Positional Obstructive Sleep Apnoea in a Sample of the Saudi Population

PURPOSE

Positional obstructive sleep apnoea (POSA) is of important clinical significance, as positional treatment can augment or obviate continuous positive airway pressure. This study aimed to determine the prevalence of POSA and its characteristics using different definitions.

METHODS

We retrospectively examined a cohort of patients who underwent polysomnography (PSG) between 2013 and 2019 at two sleep centres. Demographic data and PSG data were collected from 624 patients with an apnoea-hypopnea index (AHI) ≥ 5. POSA was defined using different criteria as follows: (1) AHI of at least twice as high in the supine position as in the lateral position (Cartwright' s definition). (2) A supine AHI ≥ 10 and a lateral AHI < 10 (Marklun's definition). (3) AHI of at least twice as high in the supine position than in the lateral position, with the lateral AHI not exceeding 5 (Mador's definition or Exclusive POSA; e-POSA). (4) AHI ≥ 15/h; a supine AHI ≥ twice that of the nonsupine AHI ≥ 20 min of sleep in the supine and nonsupine positions; and a nonsupine AHI < 15 (Bignold's definition).

RESULTS

The prevalence of POSA was 54% (Cartwright), 38.6% (Mador), 33.8% (Marklund) and 8.3% (Bignold). Multivariate regression analysis showed a body mass index (BMI) < 35 kg/m² was the only significant predictor of POSA. Mador's definition had the highest diagnostic yield (sensitivity 63%; specificity 100%; area under the receiver operating characteristic curve 90.2%).

CONCLUSION

POSA is common, but its prevalence depends on the definition used. Low BMI was identified as a significant predictor.

Vision Transformers (ViT) for Blanket-Penetrating Sleep Posture Recognition Using a Triple Ultra-Wideband (UWB) Radar System

Sleep posture has a crucial impact on the incidence and severity of obstructive sleep apnea (OSA). Therefore, the surveillance and recognition of sleep postures could facilitate the assessment of OSA. The existing contact-based systems might interfere with sleeping, while camera-based systems introduce privacy concerns. Radar-based systems might overcome these challenges, especially when individuals are covered with blankets. The aim of this research is to develop a nonobstructive multiple ultra-wideband radar sleep posture recognition system based on machine learning models. We evaluated three single-radar configurations (top, side, and head), three dual-radar configurations (top + side, top + head, and side + head), and one tri-radar configuration (top + side + head), in addition to machine learning models, including CNN-based networks (ResNet50, DenseNet121, and EfficientNetV2) and vision transformer-based networks (traditional vision transformer and Swin Transformer V2). Thirty participants (n = 30) were invited to perform four recumbent postures (supine, left side-lying, right side-lying, and prone). Data from eighteen participants were randomly chosen for model training, another six participants' data (n = 6) for model validation, and the remaining six participants' data (n = 6) for model testing. The Swin Transformer with side and head radar configuration achieved the highest prediction accuracy (0.808). Future research may consider the application of the synthetic aperture radar technique.

Accumulating Comorbidities May Promote Increasing Severity of Obstructive Sleep Apnea with Aging in Males but Not in Females

Evidence suggests an increasing apnea−hypopnea index (AHI) with aging. However, the effect of aging on sleep-related metrics, especially AHI, has been less frequently investigated within different gender-specific subpopulations by taking prominent confounding factors, e.g., obstructive sleep apnea (OSA)-related comorbidities and body mass index (BMI) into account. Therefore, we retrospectively analyzed 186 first-time polysomnographic (PSG) recordings and medical files of all patients presented to a tertiary university sleep center during a 1-year period. Six groups were formed based on age (over vs. under 55 years) and gender: PSG-related parameters (AHI, apnea-index, and hypopnea-index) were significantly higher in the older mixed-gender cohort (p = 0.0001, p = 0.0011, and p = 0.0015, respectively), and the older female cohort (p = 0.0005, p = 0.0027, and p = 0.001, respectively). Within the older male cohort, the AHI and apnea-index were significantly higher (p = 0.0067, and p = 0.0135, respectively). Inter-group comparison of the BMI showed no significant difference in any subpopulation. Within the older male cohort there were significantly more patients with arterial hypertension, diabetes mellitus, cardiovascular diseases, and chronic mental health disorders (p < 0.0001, p = 0.001, p = 0.0181, and p = 0.0454, respectively). Contrarily, within the female subpopulation there were no significant differences for the aforementioned comorbidities. In conclusion, all investigated sleep PSG-parameters increased among the older subpopulations. We suggest that Osa severity may increase with age due to the increasing accumulation of comorbidities in males, but not in females.

Investigating Cardiorespiratory Interaction Using Ballistocardiography and Seismocardiography-A Narrative Review

Ballistocardiography (BCG) and seismocardiography (SCG) are non-invasive techniques used to record the micromovements induced by cardiovascular activity at the body's center of mass and on the chest, respectively. Since their inception, their potential for evaluating cardiovascular health has been studied. However, both BCG and SCG are impacted by respiration, leading to a periodic modulation of these signals. As a result, data processing algorithms have been developed to exclude the respiratory signals, or recording protocols have been designed to limit the respiratory bias. Reviewing the present status of the literature reveals an increasing interest in applying these techniques to extract respiratory information, as well as cardiac information. The possibility of simultaneous monitoring of respiratory and cardiovascular signals via BCG or SCG enables the monitoring of vital signs during activities that require considerable mental concentration, in extreme environments, or during sleep, where data acquisition must occur without introducing recording bias due to irritating monitoring equipment. This work aims to provide a theoretical and practical overview of cardiopulmonary interaction based on BCG and SCG signals. It covers the recent improvements in extracting respiratory signals, computing markers of the cardiorespiratory interaction with practical applications, and investigating sleep breathing disorders, as well as a comparison of different sensors used for these applications. According to the results of this review, recent studies have mainly concentrated on a few domains, especially sleep studies and heart rate variability computation. Even in those instances, the study population is not always large or diversified. Furthermore, BCG and SCG are prone to movement artifacts and are relatively subject dependent. However, the growing tendency toward artificial intelligence may help achieve a more accurate and efficient diagnosis. These encouraging results bring hope that, in the near future, such compact, lightweight BCG and SCG devices will offer a good proxy for the gold standard methods for assessing cardiorespiratory function, with the added benefit of being able to perform measurements in real-world situations, outside of the clinic, and thus decrease costs and time.

Sensing Devices for Detecting and Processing Acoustic Signals in Healthcare

Acoustic signals are important markers to monitor physiological and pathological conditions, e.g., heart and respiratory sounds. The employment of traditional devices, such as stethoscopes, has been progressively superseded by new miniaturized devices, usually identified as microelectromechanical systems (MEMS). These tools are able to better detect the vibrational content of acoustic signals in order to provide a more reliable description of their features (e.g., amplitude, frequency bandwidth). Starting from the description of the structure and working principles of MEMS, we provide a review of their emerging applications in the healthcare field, discussing the advantages and limitations of each framework. Finally, we deliver a discussion on the lessons learned from the literature, and the open questions and challenges in the field that the scientific community must address in the near future.

Anthropometric Measures for the Prognosis of Obstructive Sleep Apnea in Obese

OBJECTIVE

The objective of this study was to identify, among the different anthropometric indicators, the one that shows higher discriminatory power for the prognosis of Obstructive Sleep Apnea Syndrome (OSAS).

DESIGN

Observational cross-sectional study PARTICIPANTS: Obese individuals elective to bariatric surgery METHODS: A study based on data of 758 patients aged ≥ 21 years old, of both sexes, in the pre-operatory stage of the surgical procedure of gastric bypass. Obstructive sleep apnea and obstructive sleep hypopnea were evaluated and classified through the apnea-hypopnea index, which was obtained through the examination of polysomnography. Variables were divided into two groups: individuals with and without OSAS. As predictors, measures of body mass index (BMI), neck circumference (NC), and waist circumference (WC) were used.

RESULTS

The area under the ROC curve was used to check the sensitivity and specificity. All evaluated anthropometric indicators showed statistical significance. WC: area of 0.62 (CI 95%: 0.58 - 0.67), NC: area of 0,68 (CI 95%: 0.64 - 0.72) and BMI: area of 0.58 (CI 95%: 0.54 - 0.63).

CONCLUSION

The investigated anthropometric indicators performed as good predictors of OSAS. However, NC seems to be the best anthropometric indicator for the prognosis of OSAS in obese individuals when compared to BMI and WC.

The lncRNA MRPL20-AS1 is associated with severe OSAS and downregulated upon hypoxic injury of endothelial cells

INTRODUCTION

Obstructive sleep apnea syndrome (OSAS) is the most common sleep disorder in humans. Although OSAS is clearly related to arterial hypertension, coronary artery disease, and heart failure, it remains unknown through which pathomechanisms OSAS influences cardiovascular health. Recent research has pinpointed long non-coding RNAs (lncRNA) as important molecular mediators of various cardiovascular pathologies. In this study, we have identified the lncRNA MRPL20-AS1 to be affected by OSAS in patients as well as by hypoxia in vitro.

METHODS AND RESULTS

A transcriptomic analysis was performed on peripheral blood from four patients with severe OSAS taken after one night of polygraphic assessment. We found that three lncRNAs were significantly dysregulated, of which MRPL20-AS1 was the most significant. In a larger cohort of 22 OSAS patients, MRPL20-AS1 was inversely correlated with the apnea-hypopnea index (AHI). This indicates that OSAS patients with higher AHI levels and therefore more severe OSAS had lower levels of MRPL20-AS1 in the blood. The results were recapitulated in vitro by subjecting endothelial cells to hypoxia. In these experiments, hypoxia led to a significant downregulation of MRPL20-AS1 in endothelial cells.

CONCLUSION

MRPL20-AS1 may serve as a useful tool to identify patients suffering from severe OSAS and further research should be done to evaluate the therapeutic potential of MRPL20-AS1 as a target to counteract the cardiovascular effects of OSAS.

The Impact of Marital Status and Race in Obstructive Sleep Apnea

OBJECTIVES

To examine the difference in survival of obstructive sleep apnea (OSA) based on marital status and race.

METHODS

A single academic institution with data collection from 2005 to 2015. Patients with a diagnosis of OSA based on polysomnogram were abstracted from electronic medical records. Patients were classified as "married" or "unmarried." Race was self-reported as White, Black, Asian American, Hispanic/Latinx, Middle Eastern descent, or unrecorded and gathered from the electronic medical record.

RESULTS

There were 6200 adults included. Of these, married patients composed 62.7% (n = 3890) of the patients. Patients were 51.3% White (n = 3182), 39.8% (n = 2467) were Black, and 8.9% (n = 551) were other/unrecorded. Married patients had better survival probabilities (p < .0001). Unmarried patients had 2.72 times the risk of death than those who were married (95% CI 1.78-4.20) when examining OSA survival. When examining survival of those on continuous positive airway pressure (CPAP) between married and unmarried patients, those who were unmarried had 2.00 (95% CI 1.58-2.54) times the risk of death than those who were married. Married Black patients demonstrated the best survival probabilities, followed by married White patients (p < .0001). Married patients had lower mean sleep efficiency than those that were unmarried (76.2% and 77.2%, respectively; p = .019).

CONCLUSION

Married patients with OSA had increased survival compared to their single counterparts. Married Black patients had the highest survival.

Analysis of nocturnal, hypoxia-induced miRNAs in sleep apnea patients

INTRODUCTION

Obstructive sleep apnea syndrome (OSAS) is associated with an increased cardiovascular risk. The underlying mechanisms are largely unclear. MicroRNAs (miRNAs) are RNAs circulating in the blood that can be released into the bloodstream during hypoxia. In the present study, we investigate if OSAS-induced hypoxia results in a release of miRNAs that may mediate OSAS-associated cardiovascular damage.

METHODS

Blood was sampled from 23 OSAS patients before and after a polygraphically monitored night. Total circulating RNA was isolated from the plasma and quantified using real-time qPCR. Using a Taqman miRNA array, the levels of 384 different miRNAs were compared between evening and morning after polysomnography. The most highly upregulated miRNA (miRNA-505) and four additionally upregulated miRNAs (miRNA-127, miRNA-133a, miRNA-145, and miRNA-181a) were then quantified in a bigger patient cohort individually.

RESULTS

Apnea/Hypopnea-Index (AHI) was evaluated and averaged at 26 per hour on nocturnal polygraphy. In an initial miRNA array, a total of 4 miRNAs were significantly regulated. A significant increase of miRNA-145 was observed in the larger patient cohort. No significant changes in concentration were detected for miRNA-127, miRNA-133a, miRNA-181a, and miRNA-505 in this larger cohort.

CONCLUSION

OSAS results in the nocturnal release of miRNAs into the bloodstream. Our collected data may indicate a hypoxia-induced release of miRNAs into the bloodstream of OSAS-patients. In vitro experiments are needed to confirm the secretion of these miRNAs under hypoxia and evaluate the effect on the cardio vasculature.

Association of urinary arsenic and sleep disorder in the US population: NHANES 2015-2016

Arsenic is a known carcinogen and neurotoxin and is found in the natural earth crust. Arsenic exposure can develop depression, memory dysfunction, and neurodegenerative disorder. The mechanism of arsenic toxicity on the nervous system is not known. There is a lack of research on the association between arsenic exposure and sleep disturbance in humans. This study aims to investigate the relationship between six types of urinary speciated arsenic exposure and sleep disturbance in adults from the general population using the National Health and Nutrition Examination Survey (NHANES) 2015-2016 dataset. Sleep disturbance was measured using self-reported questionnaires, asking participants if they had ever told a doctor they had trouble sleeping. We utilized multivariate logistic regression analysis using complex survey procedures to examine the association between six types of urinary arsenic concentration and trouble sleeping. The total sample included 1,611 adults who were 20 years and older. Of the study participants, 30.0% had trouble sleeping. Compared to individuals with urinary arsenous acid below the lower level of detection (LLOD), those with urinary arsenous acid at or above the detection limit had lower odds of trouble sleeping [odds ratio: 0.72 (95% confidence interval 0.51-1.00, p-value: 0.05)]. The other five types of urinary speciated arsenic studied (arsenic acid, arsenobetaine, arsenocholine, dimethylarsinic acid, monomethylarsonic acid) were not associated with a sleep disorder. More studies are required to confirm or refute these findings.

Evaluation of the Relationship between Occupational Accidents and Obstructive Sleep Apnea Risk among Employees of a University Hospital

Context

Occupational accidents are still one of the important causes of morbidity and mortality. Sleep apnea is a significant risk factor for occupational accidents in hospitals.

Aims

To determine the frequency of occupational accidents and their relationship with the risk of obstructive sleep apnea (OSAS).

Settings and Design

Cross-sectional study in a hospital setting.

Methods and Material

This study was conducted on 331 hospital workers between 2019-2020. Accidents from the Social Security Institution records were used. The risk of OSAS was evaluated with Berlin Survey, daytime sleepiness with Epworth Sleepiness Scale, sleep quality with Pittsburg Sleep Quality Scale.

Statistical Analysis

The Chi-square test was used for analysis; P < 0.05 was accepted as a statistical significance value.

Results

Of the participants, 231 (69.8%) were female. Their ages ranged between 19 and 55; the mean age was 33.8 ± 8.0 years. The frequency of occupational accidents was 8.8%, 51.4% had a high risk of OSAS, 80.4% had high daytime sleepiness, and 53.5% had poor sleep quality.

Conclusion

The study group had a high risk of sleep disorders. No relationship was found between sleep disorders and occupational accidents. More comprehensive studies are needed to clarify this relationship.

Oral health problems linked to obstructive sleep apnea are not always recognized within dental care-As described by dental professionals

Objectives

Obstructive sleep apnea (OSA) has an impact on an individual's quality of life and general health, and can also affect their oral health. The patient's experiences, together with intraoral signs and symptoms could indicate the presence of OSA. Knowledge that the patient has, or is at high risk for having OSA can help the dental healthcare provider maintain the oral health and general health for these patients. The purpose was to explore dentists and dental hygienists' experiences when encountering adult patients with potential, untreated and treated OSA.

Methods

A qualitative inductive approach was used. Experienced dentists and dental hygienists working within Swedish Public Dental Service were strategically selected. Semi‐structured face‐to‐face interviews were performed followed by qualitative content analysis.

Results

Interviews from 13 participants, seven dental hygienist and six dentists, led to three areas describing varied experience: Importance of the patient encounter and identifying intraoral signs both of which describe experiences related to the importance of the initial unstructured conversation and focused clinical assessments, and strategies for nurturing care which point to interest about care, treatment, and collaborations with medical health care providers.

Conclusions

Dental professionals are not able to consistently recognize patients who have, or are at high risk for OSA. During the patient encounter, is it important to determine if a patient is at risk for, or has oral signs of OSA.

Obstructive Sleep Apnea in Patients with Head and Neck Cancer—More than Just a Comorbidity?

Obstructive sleep apnea is the most common type of sleep-disordered breathing with growing prevalence. Its presence has been associated with poor quality of life and serious comorbidities. There is increasing evidence for coexisting obstructive sleep apnea in patients suffering from head and neck cancer, a condition that ranks among the top ten most common types of cancer worldwide. Routinely, patients with head and neck cancer are treated with surgery, radiation therapy, chemotherapy, immunotherapy or a combination of these, all possibly interfering with the anatomy of the oral cavity, pharynx or larynx. Thus, cancer treatment might worsen already existing obstructive sleep apnea or trigger its occurrence. Hypoxia, the hallmark feature of obstructive sleep apnea, has an impact on cancer biology and its cure. Early diagnosis and sufficient treatment of coexisting obstructive sleep apnea in patients with head and neck cancer may improve quality of life and could also potentially improve oncological outcomes.

PSG-Audio, a scored polysomnography dataset with simultaneous audio recordings for sleep apnea studies

The sleep apnea syndrome is a chronic condition that affects the quality of life and increases the risk of severe health conditions such as cardiovascular diseases. However, the prevalence of the syndrome in the general population is considered to be heavily underestimated due to the restricted number of people seeking diagnosis, with the leading cause for this being the inconvenience of the current reference standard for apnea diagnosis: Polysomnography. To enhance patients' awareness of the syndrome, a great endeavour is conducted in the literature. Various home-based apnea detection systems are being developed, profiting from information in a restricted set of polysomnography signals. In particular, breathing sound has been proven highly effective in detecting apneic events during sleep. The development of accurate systems requires multitudinous datasets of audio recordings and polysomnograms. In this work, we provide the first open access dataset, comprising 212 polysomnograms along with synchronized high-quality tracheal and ambient microphone recordings. We envision this dataset to be widely used for the development of home-based apnea detection techniques and frameworks.

The 6-Minute Walk Test and Anthropometric Characteristics as Assessment Tools in Patients with Obstructive Sleep Apnea Syndrome. A Preliminary Report during the Pandemic

Patients with obstructive sleep apnea syndrome (OSAS) exhibit low cardio-fitness impact, attributed to fragmented sleep architecture and associated pathophysiological sequelae. The purpose of our study was to investigate fitness indicators during 6-min walk test (6MWT) and oxidative stress markers in apnea-hypopnea index (AHI) in OSAS patients stratified by severity. A total of 37 newly diagnosed patients, comorbidity-free, were divided into two groups: (Moderate OSAS (n = 12), defined as ≥ 15 AHI < 30 events per hour; Age: 50.7 ± 7.2 years, BMI: 32.5 ± 4.0 kg/m2 vs. Severe OSAS (n = 25), defined as AHΙ ≥ 30 events per hour; Age: 46.3 ± 10.4 years, BMI: 33.3 ± 7.9 kg/m2). Measurements included demographics, anthropometric characteristics, body composition, blood sampling for reactive oxygen metabolites' levels (d-ROM) and plasma antioxidant capacity (PAT), and followed by a 6MWT. AHI was significantly associated with d-ROMs levels, chest circumference in maximal inhalation and exhalation (Δchest), neck circumference, as well as 6MWT-derived indices. In conclusion, our study determines bidirectional interrelationships between OSAS severity and anthropometrics, body composition, and fitness metrics. These findings indicate that the impact of OSAS should be evaluated well beyond polysomnography-derived parameters.

Prevalence of Obstructive Sleep Apnea in Orthodontic Patients with Different Skeletal Classes Using STOP-BANG Questionnaire: An Observational Study

AIM: The aim of the study was to determine the prevalence of obstructive sleep apnea (OSA) in orthodontic adult patients with different skeletal classes and no pathology in the airway as detected from the lateral cephalometric radiographs using the STOP-BANG questionnaire. METHODS: The sample comprised 309 subjects (152 males and 157 females) collected from the Egyptian population presented to the orthodontic follicular unit extraction for treatment. The sample was divided into three groups based on the anteroposterior relationship between maxilla and mandible (ANB angle) as evident from pretreatment lateral cephalometric. Patients were asked to fill out general medical history, sign a consent form, and fill in the STOP-BANG questionnaire. Patient’s neck size and height were measured using tape measuring tool and weighing scale, respectively. Body mass index (BMI) was obtained. After submission of the questionnaire, scores were measured for each patient to evaluate the severity of OSA. RESULTS: Comparison between OSA risk in the three classes showed no statistically significant difference (p = 0.791, effect size = 0.052). CONCLUSIONS: STOP-BANG questionnaire showed that there was no statistically significant difference in the prevalence of OSA between different skeletal classes.

Moderating effects of dysregulation and fear of positive emotions on the relationship between posttraumatic stress disorder symptoms and positive memory count

OBJECTIVES

We examined moderating effects of positive emotion dysregulation and fear of positive emotions in the relation between posttraumatic stress disorder (PTSD) severity and positive memory count.

METHOD

Participants were 205 trauma-exposed community individuals (Mage  = 35.44; 61.50% female).

RESULTS

Moderation analyses indicated interaction effects of PTSD severity with nonacceptance of positive emotions (b = -0.01, p = .002) and difficulties with goal-directed behaviors when experiencing positive emotions (b = -0.01, p = .006) on positive memory count.

CONCLUSIONS

Greater PTSD severity was associated with more specific positive memories when individuals reported less nonacceptance of positive emotions and fewer difficulties engaging in goal-directed behaviors in the context of positive emotions. Greater PTSD severity was associated with fewer specific positive memories when individuals reported greater nonacceptance of positive emotions and greater difficulties engaging in goal-directed behaviors in the context of positive emotions. Results support addressing positive emotion dysregulation in memory-focused interventions for PTSD.

Impact of counterclockwise rotation of the occlusal plane on the mandibular advancement, pharynx morphology, and polysomnography results in maxillomandibular advancement surgery for the treatment of obstructive sleep apnea patients

PURPOSE

Evaluate the impact of counterclockwise rotation of the occlusal plane (CCWROP) on pharynx morphology and polysomnography in maxillomandibular advancement (MMA) surgery to treat obstructive sleep apnea (OSA) patients.

METHODS

Prospective clinical trial of patients with OSA treated by MMA. Computed tomography and polysomnography were performed pre- and postoperatively and the parameters were compared. The surgery classified the patients into two groups: with (R) and without (NR) CCWROP.

RESULTS

The study sample comprised 38 individuals: R (n = 19) and NR (n = 19). An anterior mandible advancement of 0.71 mm was identified for each degree of CCWROP (p < 0.001). As for polysomnography, the apnea-hypopnea index was reduced by 80% and 62% in R and NR, showing final values of 6.8 and 13.0, respectively. The apnea index changed equally in both groups. Reduction of 68 and 26% in the hypopnea index was observed for R and NR, respectively, with no statistically significant difference. Total volume increased by 45% in R and 30% in NR. Retropalatal and retrolingual volumes increased by 49% and 4% in R and 43% and 15% in NR, respectively. The minimum axial area increased by 92% in the retropalatal region and 97% in the retrolingual region in R, whereas these increases were of 76% and 31% in NR, respectively.

CONCLUSION

Anterior mandibular advancement of 0.71 mm for each degree of CCWROP is of great importance for surgical planning. As a result of this resource, individuals in R presented better results than those in NR in all parameters assessed, especially regarding the retrolingual region.

Drug-Resistant Epilepsy and Obstructive Sleep Apnea: Exploring a Link Between the Two

Drug-resistant epilepsy accounts for approximately one third of all epilepsy cases; yet its exact etiopathogenesis still remains under intense exploration. Several factors have been advocated for predicting drug resistance in patients with epilepsy. Obstructive sleep apnea (OSA) is a commonly prevalent sleep disorder that exhibits a bidirectional and strong comorbidity with epilepsy. The exact pathophysiology of this comorbidity is not yet clearly explained. This study analyzes the relationship between drug-resistant epilepsy and OSA, and the findings indicate a strong role of rapid eye movement sleep (REMS) in the pathogenesis of this relationship. It also emerges from the study that REMS reduction is a prominent feature of OSA, and drug resistance in patients with epilepsy and treatment of OSA has been shown to restore REMS in several studies with concomitant improvement in seizure control.

Bypassing TBI: Metabolic Surgery and the Link between Obesity and Traumatic Brain Injury-a Review

Obesity is a common outcome of traumatic brain injury (TBI) that exacerbates principal TBI symptom domains identified as common areas of post-TBI long-term dysfunction. Obesity is also associated with increased risk of later-life dementia and Alzheimer's disease. Patients with obesity and chronic TBI may be more vulnerable to long-term mental abnormalities. This review explores the question of whether weight loss induced by bariatric surgery could delay or perhaps even reverse the progression of mental deterioration. Bariatric surgery, with its induction of weight loss, remission of type 2 diabetes, and other expressions of the metabolic syndrome, improves metabolic efficiency, leads to reversal of brain lesions seen on imaging studies, and improves function. These observations suggest that metabolic/bariatric surgery may be a most effective therapy for TBI.

The relationship between risk of obstructive sleep apnea and other sleep problems, depression, and anxiety in adolescents from a community sample

Obstructive sleep apnea (OSA) is highly related to mental health problems, such as depression and anxiety. However, previous studies on OSA and depression and anxiety have mostly been conducted in the adult population. We aimed to (1) screen for risk of OSA in a sample of adolescents from the general population using self-report questionnaires and (2) examine whether there are differences between the high- and low-risk groups for OSA in depressive and anxiety symptoms, self-esteem, and sleep-related variables. The data of 793 students (age range: 12-17 years old) were analyzed. The participants were assigned to the high-risk (n = 202, 25.5%) or the low-risk group (n = 591, 74.5%) of OSA. The participants in the high-risk group had more severe anxiety symptoms, lower self-esteem, insomnia, excessive daytime sleepiness, and higher BMI compared those in the low-risk group. This study shows that it is possible to efficiently screen for risks of various problems associated with OSA in adolescents using an easy and simple screening tool.

Relation of positive memory recall count and accessibility with post-trauma mental health

Positive memory encoding and retrieval deficits have an empirical relation with several post-trauma outcomes. Drawing from the Contractor et al. model, we examined relations between positive memory characteristics and post-trauma mental health indicators. A trauma-exposed community sample of 203 participants (Mage = 35.40 years; 61.10% female) was recruited via Amazon's Mechanical Turk. Participants completed measures of posttraumatic stress disorder (PTSD; PTSD Checklist for DSM-5), depression (Patient Health Questionnaire-9), posttraumatic cognitions (Posttraumatic Cognitions Inventory), affect (Positive and Negative Affect Schedule), count/number of recalled specific positive memories (Autobiographical Memory Test) and accessibility of a specific positive memory (i.e., subjective ease of recalling details of a memory; Memory Experiences Questionnaire-Short Form). Linear regression results indicated that PTSD intrusion severity, PTSD negative alterations in cognitions and mood (NACM) severity, PTSD alterations in arousal and reactivity (AAR) severity, self-blame, and positive affect significantly and negatively predicted the count of specific positive memories. Further, PTSD NACM severity, PTSD AAR severity, negative cognitions about the self, and negative affect significantly and negatively predicted accessibility of a specific positive memory. Thus, count/accessibility of specific positive memories was associated with several post-trauma mental health indicators; this highlights the relevance and potential impact of integrating positive memories into trauma treatment.

Increased risk of sleep apnoea among primary headache disorders: a nationwide population-based longitudinal study

Background

Primary headache disorders (PHDs) are associated with sleep problems. It is suggested that headache and sleep disorder share anatomical and physiological characteristics. We hypothesised that patients with PHDs were exposed to a great risk for developing sleep apnoea (SA).

Methods

In this retrospective longitudinal study, the data obtained from the Longitudinal Health Insurance Database in Taiwan were analysed. The study included 1346 patients with PHDs who were initially diagnosed and 5348 patients who were randomly selected and age/sex matched with the study group as controls. PHDs, SA, comorbidities and other confounding factors were defined based on International Classification of Diseases, Ninth Revision, Clinical Modification. Cox proportional hazards regressions were employed to examine adjusted HRs after adjusting with confounding factors.

Results

Our data revealed that patients with PHDs had a higher risk (HR 2.17, 95% CI 1.259 to 3.739, p<0.05) to develop SA compared with matched cohorts, whereas patients with migraine exhibited a high risk (HR 2.553, 95% CI 1.460 to 4.395, p<0.01). The results showed that patients with PHDs aged 18–44 exhibited highest risk of developing SA. In addition, males with PHDs exhibited an HR 3.159 (95% CI 1.479 to 6.749, p<0.01) for developing SA, respectively. The impact of PHDs on SA risk was progressively increased by various follow-up time intervals.

Conclusion

Our results suggest that PHDs are linked to an increased risk for SA with sex-dependent and time-dependent characteristics.

The Prevalence of Sleep Apnea in Iran: a Systematic Review and Meta-Analysis

BACKGROUND

Sleep apnea is a common sleep disorder which is associated with cardiovascular diseases, diabetes and stroke. Different studies conducted in Iran have reported different prevalence for sleep apnea. The aim of the present study was to determine the prevalence of sleep apnea in Iran.

MATERIALS AND METHODS

In this study, 42 studies that have been published in Farsi and English languages were selected with no time limit up to the March of 2018. Article search was conducted using "prevalence", "frequency", "sleep apnea" and "obstructive sleep apnea" keywords in Scientific Information Database (SID), MagIran, Google Scholar, Science Direct, PubMed and Scopus databases. Data were analyzed using meta-analysis and random effect model methods. Heterogeneity between the studies was evaluated using I² test. Data were analyzed using Stata software version 11.2.

RESULTS

The total prevalence of metabolic syndrome was 44% (95% CI: 35% to 53%). The highest prevalence of sleep apnea distinguished by the disease belonged to patients with sleep disorders (74%, 95% CI: 66%-82%), diabetes mellitus (61%; 95% CI: 46%-76%) and cardiovascular disease (55%; 95% CI: 47%-63%).

CONCLUSION

Given high prevalence of sleep apnea in Iran, identifying people at risk and providing instructional materials for controlling and treating sleep apnea is necessary.

Mask interface for continuous positive airway pressure therapy: selection and design considerations

INTRODUCTION

Continuous positive airway pressure (CPAP) therapy is a clinical treatment for moderate or severe obstructive sleep apnea (OSA). Commercial CPAP mask designs normally come in standard sizes and the configuration is not commonly tailored to the patients' characteristics such as face topology, skin sensitivity, and severity of OSA syndrome; however, an optimal mask/interface selection is a key factor influencing the compliance and effectiveness of CPAP treatment.

AREAS COVERED

This review investigates the conventional CPAP mask design, its effect on OSA treatment, and the related risk factors that can lead to skin damage after long-term repeated use. Through a literature search on common databases, Scopus, PubMed, and Google Scholar, we identified reported facts on the influence of the mask interface and current trends toward customized devices.

EXPERT COMMENTARY

There is potential for optimizing the CPAP mask fit by adapting the interface to the patients' individual characteristics. This holds particularly true for users with abnormal features or simply outside conventional industry sizing standards. Enabling technologies for undertaking this adaptation include reverse engineering, computational modeling, and additive manufacturing. There is to date no integrated system that integrates those elements into a standard solution, but several studies have shown its effectiveness for specific cohorts.

HLA-DRB1 allele frequency and immunological response in obstructive sleep apnea syndrome in Turkish population

INTRODUCTION

Obstructive sleep apnea syndrome (OSAS) is a complex, polygenic and multifactorial disease. The relationship between Human Leukocyte Antigen (HLA) polymorphisms and sleep disturbances has been established, but the relationship with HLA alleles has not been fully clarified. In addition, sleep deprivation in OSAS patients can cause changes that affect the components and responses of the immune system.

OBJECTIVE

The aim of this study has assessed the effect of HLA-DRB1 alleles on OSAS disease and the changes occurring in immune response cells in Turkish population.

METHOD

OSAS was diagnosed by polysomnography and severity was determined. PCR SSP and flow cytometry methods were used.

RESULTS

We found that DRB1*07 and DRB1*11 were significantly increased in the control group and DRB1*03 and DRB1*08 alleles in the patient group in our study (P = 0.048, P = 0.005, P = 0.012 and P = 0.030, respectively). DRB1*08 was significantly increased in patients with severe OSAS (P = 0.002). When the immunological response was examined in OSAS patients, there was a decrease in CD4, an increase in HLA DR, CD8 and NK cells (P = 0.002, P = 0.00, P = 0.020, P = 0.040, respectively). We also found that CD19 was reduced in severe OSAS (P = 0.048).

CONCLUSION

These results suggest that the DRB1*03 allele may play a predisposing role in OSAS disease and that the DRB1*08 allele may be related to the severity of the disease. In addition, the decrease in CD4, CD8, NK and HLA DR increase in this disease suggests that the disease causes impairment of the immunological system and may be associated with autoimmunity.

When a private community neurology practice executes home sleep apnea testing: benefits identified and lessons learned in a retrospective observational study

OBJECTIVE

To investigate the feasibility and utility of a private community neurology practice-initiated home sleep apnea testing (HSAT) program.

METHODS

A private community neurology practice conducted HSAT on patients clinically identified as high risk for obstructive sleep apnea (OSA). An academic board-certified sleep specialist performed all study interpretations. The presence and severity of OSA and its association with patient demographics (eg, sex, age) and comorbid health conditions relevant to OSA were evaluated.

RESULTS

During 2011-2014, 147 consecutive patients clinically identified as highly "at risk for OSA" during their neurological visit underwent HSAT. Sixty-one percent (n=89) of patients had a "positive" study with evidence of an apnea-hypopnea index of greater than 5 events per hour. Of those, 37% (n=54) had mild OSA and 24% (n=35) had moderate-severe OSA. OSA was more common among men (54%, n=48) and in individuals with a previous documented history of depression (33%, n=48) and hypertension 44% (n=64). OSA treatment was ordered in 44% (n=39) of patients by the neurologists or by a sleep specialist. Twenty-four percent (n=21) of all patients studied were referred to a sleep specialist.

CONCLUSION

Implementation of HSAT in a (nonsleep) private community neurology practice in collaboration with an academic sleep program is recommended. Based on this observational study, community-based neurological practices and board-certified sleep specialists should consider teaming up to develop HSAT collaborative programs to open new sleep care access pathways for neurological patients often at risk for sleep apnea.

A pilot study on the biomechanical assessment of obstructive sleep apnea pre and post bariatric surgery

Obesity is a major risk factor for obstructive sleep apnea patients. In obese patients the severity of this risk can be reduced by bariatric surgery. This pilot study investigates the perioperative effects of bariatric surgery on obstructive sleep apnea and on the physical and biomechanical characteristics of the upper airway. Polysomnography and computer tomography data for 10 morbid obese patients promoted for bariatric surgery were conducted before surgery and at 6 and 12 months postoperatively for assessment of the oropharyngeal anatomy, and subsequent three-dimensional modelling of the airway. Mean values for the apnea/hypopnea index and body mass index significantly reduced after surgery. To combine the effect of changes in the upper airway volume and body mass index, a new volume body mass index is introduced. This index increases with a successful bariatric surgery. Although bariatric surgery leads to an effective weight reduction for all age groups, for obstructive sleep apnea patients it may be effective for middle age, less effective for 50-60 years, and further less effective for patients over the age of 60 years.

Quantitative EEG in obstructive sleep apnea syndrome: a review of the literature

Obstructive sleep apnea syndrome (OSAS) is characterized by the recurrent cessation (apnea) or reduction (hypopnea) of airflow due to the partial or complete upper airway collapse during sleep. Respiratory disturbances causing sleep fragmentation and repetitive nocturnal hypoxia are responsible for a variety of nocturnal and daytime complaints of sleep apnea patients, such as snoring, daytime sleepiness, fatigue, or impaired cognitive functions. Different techniques, such as magnetic resonance imaging, magnetic resonance spectroscopy, and positron emission tomography, are used to evaluate the structural and functional changes in OSAS patients. With quantitative electroencephalographic (qEEG) analysis, the possible existence of alterations in the brain electrical activity of OSAS patients can be investigated. We review the articles on qEEG results of sleep apnea patients and summarize the possible explanations of these qEEG measures. Finally, we review the impact of continuous positive airway pressure (CPAP) treatment on these alterations to assess whether CPAP use can eliminate alterations in the brain activity of OSAS patients.