Clinical practice. Obstructive sleep apnea

High-sensitivity QCM humidity sensor based on chitosan/carboxymethylated multiwalled carbon nanotubes composite for non-contact respiratory monitoring

Respiratory humidity is an important indicator that can reflect respiratory disorders and is easily accessible in daily life, thus attracting attention in non-contact home respiratory monitoring systems. In this work, a high-sensitivity quartz crystal microbalance (QCM) humidity sensor based on a chitosan/carboxymethylated multiwalled carbon nanotubes composite coating is developed with a response time of 36 s and a recovery time of 38 s. The humidity variations from 11 to 97 % can be detected while the wet hysteresis is 0.95 % RH. The sensor also exhibits good repeatability and stability. The physicochemical characterizations of the materials reveal the mechanism of the rapid humidity response, i.e., compared to the physically blended CS with MWCNT, the crosslinking CS-MWCNT formed the new intercalation by stronger hydrogen and amide bonding, which leads to the homogeneous coverage of CS on MWCNT, exposing more active sites and facilitating the binding rate of water molecules. Combined with respiration monitoring, the sensor is able to accurately monitor human respiration rate and depth in real time, effectively predicting and differentiating between different types of obstructive sleep apnea syndromes, providing a fast and reliable solution for daily health monitoring.

A Machine Learning Prediction Model of Adult Obstructive Sleep Apnea Based on Systematically Evaluated Common Clinical Biochemical Indicators

Objective

Obstructive sleep apnea (OSA) is a common and potentially fatal sleep disorder. The purpose of this study was to construct an objective and easy-to-promote model based on common clinical biochemical indicators and demographic data for OSA screening.

Methods

The study collected the clinical data of patients who were referred to the Sleep Medicine Center of the Second Affiliated Hospital of Fujian Medical University from December 1, 2020, to July 31, 2023, including data for demographics, polysomnography (PSG), and 30 biochemical indicators. Univariate and multivariate analyses were performed to compare the differences between groups, and the Boruta method was used to analyze the importance of the predictors. We selected and compared 10 predictors using 4 machine learning algorithms which were "Gaussian Naive Bayes (GNB)", "Support Vector Machine (SVM)", "K Neighbors Classifier (KNN)", and "Logistic Regression (LR)". Finally, the optimal algorithm was selected to construct the final prediction model.

Results

Among all the predictors of OSA, body mass index (BMI) showed the best predictive efficacy with an area under the receiver operating characteristic curve (AUC) = 0.699; among the predictors of biochemical indicators, triglyceride-glucose (TyG) index represented the best predictive performance (AUC = 0.656). The LR algorithm outperformed the 4 established machine learning (ML) algorithms, with an AUC (F1 score) of 0.794 (0.841), 0.777 (0.827), and 0.732 (0.788) in the training, validation, and testing cohorts, respectively.

Conclusion

We have constructed an efficient OSA screening tool. The introduction of biochemical indicators in ML-based prediction models can provide a reference for clinicians in determining whether patients with suspected OSA need PSG.

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.

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

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

Insights into the Use of Point-of-Care Ultrasound for Diagnosing Obstructive Sleep Apnea

Obstructive sleep apnea (OSA) is a sleeping disorder caused by complete or partial disturbance of breathing during the night. Existing screening methods include questionnaire-based evaluations which are time-consuming, vary in specificity, and are not globally adopted. Point-of-care ultrasound (PoCUS), on the other hand, is a painless, inexpensive, portable, and useful tool that has already been introduced for the evaluation of upper airways by anesthetists. PoCUS could also serve as a potential screening tool for the diagnosis of OSA by measuring different airway parameters, including retropalatal pharynx transverse diameter, tongue base thickness, distance between lingual arteries, lateral parapharyngeal wall thickness, palatine tonsil volume, and some non-airway parameters like carotid intima-media thickness, mesenteric fat thickness, and diaphragm characteristics. This study reviewed previously reported studies to highlight the importance of PoCUS as a potential screening tool for OSA.

Sleep-Energy: An Energy Optimization Method to Sleep Stage Scoring

Sleep is essential for physical and mental health. Polysomnography (PSG) procedures are labour-intensive and time-consuming, making diagnosing sleep disorders difficult. Automatic sleep staging using Machine Learning (ML) - based methods has been studied extensively, but frequently provides noisier predictions incompatible with typical manually annotated hypnograms. We propose an energy optimization method to improve the quality of hypnograms generated by automatic sleep staging procedures. The method evaluates the system's total energy based on conditional probabilities for each epoch's stage and employs an energy minimisation procedure. It can be used as a meta-optimisation layer over the sleep stage sequences generated by any classifier that generates prediction probabilities. The method improved the accuracy of state-of-the-art Deep Learning models in the Sleep EDFx dataset by 4.0% and in the DRM-SUB dataset by 2.8%.

A comparative study of three-dimensional airway changes after fibula flap reconstruction for benign and malignant tumours in the anterior mandible

Surgical treatment of tumours in the anterior mandible and surrounding tissues may result in defects which can be restored by a fibula free flap. The upper airway may change during this process. The purpose of this retrospective study was to evaluate upper airway changes after fibula free flap reconstruction. A total of 37 patients who underwent anterior mandibulectomy and fibula free flap reconstruction between 2012 and 2020 were recruited. Patients with benign and malignant tumours involving the anterior mandible were included. Spiral computed tomography was performed 1 week preoperatively, 1 week postoperatively, and at> 1 year (range 12-23 months) after surgery. Cross-sectional areas and volumes of the upper airway were measured. Data were analysed by two-way analysis of variance. The upper airway in the malignant tumour group showed an increasing trend, especially at the soft palate and tongue base levels (P < 0.01). In the benign tumour group, the upper airway showed no significant changes. The location of the minimum cross-sectional area moved downwards in both groups, and the area increased in the malignant tumour group during long-term follow-up. Upper airway obstruction is less likely to occur in the long term after surgical resection of anterior mandible malignancies and fibula free flap reconstruction.

Contactless sleep posture measurements for demand-controlled sleep thermal comfort: A pilot study

Thermal comfort during sleep is essential for both sleep quality and human health while sleeping. There are currently few effective contactless methods for detecting the sleep thermal comfort at any time of day or night. In this paper, a vision-based detection approach for human thermal comfort while sleeping was proposed, which is intended to avoid overcooling/overheating supply, meet the thermal comfort needs of human sleep, and improve human sleep quality and health. Based on 438 valid questionnaire surveys, 10 types of thermal comfort sleep postures were summarized. By using a large number of data captured, a fundamental framework of detection algorithm was constructed to detect human sleeping postures, and corresponding weighting model was established. A total of 2.65 million frames of posture data in natural sleep status were collected, and thermal comfort-related sleep postures dataset was created. Finally, the robustness and effectiveness of the proposed algorithm were validated. The validation results show that the sleeping posture and human skeleton keypoints can be used for estimating sleeping thermal comfort, and the the quilt coverage area can be fused to improve the detection accuracy.

Association between obstructive sleep apnea syndrome and bone mineral density in adult orthodontic populations

OBJECTIVE

To determine the association between obstructive sleep apnea syndrome (OSAS) and predicted bone mineral density (BMD) in adults presenting for orthodontic treatment.

METHODS

This retrospective cross-sectional study included 38 adults divided into OSAS and non-OSAS groups. Using pre-treatment CBCT images, radiographic density (RD) of left and right lateral regions of the 1st cervical vertebrae and dens of the 2nd cervical vertebrae were measured as an indicator for BMD.

RESULTS

When controlling for age, sex, and BMI, the mean RD was significantly lower in the OSAS group compared to the non-OSAS group (left CV1: 36.69 ± 84.50 vs. 81.67 ± 93.25 Hounsfield Units [HU], respectively, p = 0.031; right CV1: 30.59 ± 81.18 vs. 74.26 ± 91.81 HU, p = 0.045; dens: 159.25 ± 115.96 vs. 223.94 ± 106.09 HU, p = 0.038).

CONCLUSION

Adults with OSAS have lower values for predicted BMD than those without OSAS.

SANReSP: A new Italian questionnaire to screen patients for obstructive sleep apnea

Purpose

Obstructive sleep apnea (OSA) is a common, prevalent, and underdiagnosed disorder. Its lack of diagnosis and treatment is associated with increased morbidity and mortality. Previous screening questionnaires investigated parameters including body mass index, age, neck circumference, and sex, in addition to symptoms. This study aimed to validate a new Italian, self-administered, and easy-to-use six-item questionnaire that evaluates only subjective symptoms.

Patients and methods

The present study included 2622 patients (male, 2011; female, 611). Patients who were at least 18 years old, spoke Italian, referred to our sleep clinic for possible OSA, and completed the self-administered SANReSP questionnaire were recruited for the study. The predictive performance of the questionnaire was also evaluated.

Results

Nocturnal study showed 89.9% of OSA patients had apnea-hypopnea index (AHI) ≥ 5/h; 68.7%, AHI ≥ 15/h; and 48.2%, AHI ≥ 30/h. The optimal SANReSP score for AHI ≥ 5/h was >3 with a sensitivity and specificity of 74.76% and 67.92%, respectively, and an area under receiver operating characteristic curve (ROC) of 0.76. For moderate–severe OSA, the optimal SANReSP score was >3 (sensitivity, 78.18%; specificity, 46.53%; ROC, 0.66). For severe OSA, the optimal SANReSP score was >4 (sensitivity, 59.10%; specificity, 64.73%; ROC, 0.65). The probability of OSA increased with higher SANReSP scores (98.7% and 97.9% in men and women, respectively).

Conclusion

The SANReSP questionnaire is a short, easy-to-use, and self-administered screening tool for OSA. Its performance is similar to that of other widely used questionnaires; furthermore, it is advantageous in that it does not require anthropometric measurements.

Development and assessment of a risk prediction model for moderate-to-severe obstructive sleep apnea

Background

OSA is an independent risk factor for several systemic diseases. Compared with mild OSA, patients with moderate-to-severe OSA have more severe impairment in the function of all organs of the body. Due to the current limited medical condition, not every patient can be diagnosed and treated in time. To enable timely screening of patients with moderate-to-severe OSA, we selected easily accessible variables to establish a risk prediction model.

Method

We collected 492 patients who had polysomnography (PSG), and divided them into the disease-free mild OSA group (control group), and the moderate-to-severe OSA group according to the PSG results. Variables entering the model were identified by random forest plots, univariate analysis, multicollinearity test, and binary logistic regression method. Nomogram were created based on the binary logistic results, and the area under the ROC curve was used to evaluate the discriminative properties of the nomogram model. Bootstrap method was used to internally validate the nomogram model, and calibration curves were plotted after 1,000 replicate sampling of the original data, and the accuracy of the model was evaluated using the Hosmer-Lemeshow goodness-of-fit test. Finally, we performed decision curve analysis (DCA) of nomogram model, STOP-Bang questionnaire (SBQ), and NoSAS score to assess clinical utility.

Results

There are 6 variables entering the final prediction model, namely BMI, Hypertension, Morning dry mouth, Suffocating awake at night, Witnessed apnea, and ESS total score. The AUC of this prediction model was 0.976 (95% CI: 0.962–0.990). Hosmer-Lemeshow goodness-of-fit test χ² = 3.3222 (P = 0.1899 > 0.05), and the calibration curve was in general agreement with the ideal curve. The model has good consistency in predicting the actual occurrence of moderate-to-severe risk, and has good prediction accuracy. The DCA shows that the net benefit of the nomogram model is higher than that of SBQ and NoSAS, with has good clinical utility.

Conclusion

The prediction model obtained in this study has good predictive power for moderate-to-severe OSA and is superior to other prediction models and questionnaires. It can be applied to the community population for screening and to the clinic for prioritization of treatment.

Effect of Different Maxillary Oral Appliance Designs on Respiratory Variables during Sleep

This study aimed to analyze the efficacy of maxillary oral appliance (MOA) designs on respiratory variables during sleep. At baseline, 23 participants underwent a sleep test with a portable device for two nights and were categorized as participants with mild obstructive sleep apnea (mild-OSA) (n = 13) and without OSA (w/o-OSA) (n = 10). Three types of MOAs, standard-OA (S-OA), palatal covering-OA (PC-OA), and vertically increasing-OA (VI-OA), were each worn for three nights, and sleep tests with each MOA were performed with a portable device for two nights. Based on the average of the respiratory event index (REI) values for the two nights for each MOA, w/o-OSA participants with an REI ≥ 5.0 were defined as the exacerbation group and those with an REI < 5.0 as the non-exacerbation group. In mild-OSA participants, an REI ≥ 15.0 or REI ≥ baseline REI × 1.5 were defined as the exacerbation group and those with an REI < 15.0 and REI < baseline REI × 1.5 were defined as the non-exacerbation group. The percentage of the exacerbation and non-exacerbation groups with MOA was evaluated in the w/o-OSA and mild-OSA participants. The maxillary and mandibular dental-arch dimension was compared by dentition model analysis. The exacerbation group in w/o-OSA participants (n = 10) comprised 10.0% participants (n = 1) with S-OA, 40.0% (n = 4) with PC-OA, and 30.0% (n = 3) with VI-OA. The exacerbation group in the mild-OSA participants (n = 13) comprised 15.4% subjects (n = 2) with S-OA, 23.1% (n = 3) with PC-OA, and 23.1% (n = 3) in VI-OA. In the model analysis for w/o-OSA, the posterior dental arch width was significantly greater in the exacerbation group than in the non-exacerbation group wearing S-OA (p < 0.05). In addition, the ratio of the maxillary to mandibular dental arch width (anterior dental arch width) was significantly greater in the exacerbation group than in the non-exacerbation group for both PC-OA and VI-OA (p < 0.05). In mild-OSA, the maxillary and mandibular dental arch lengths and the ratio of maxillary to mandibular dental arch width (posterior dental arch width) were significantly smaller in the exacerbation group than in the non-exacerbation group for S-OA (p < 0.05). This study confirmed that wearing an MOA by w/o-OSA and mild-OSA participants may increase the REI during sleep and that PC-OA and VI-OA may increase the REI more than S-OA. The maxillary and mandibular dental-arch dimensions may affect the REI when using an MOA.

Integrating the precision, sleep, and aerospace medicine fields: a systematic review of the genetic predisposition for obstructive sleep apnea in military aviation

PURPOSE

Obstructive sleep apnea (OSA) is the most common pathologic sleep disorder with an estimated prevalence in the USA of up to 25% of adult males. With military aviation being heavily comprised of adult men, the impact of OSA on flying operations is concerning as OSA is disqualifying for all flying classes in the US Air Force. In order to minimize the impact of OSA on operations, early identification of at-risk patients is critical in disease management. Individuals could be identified for whom regular polysomnography testing may reveal OSA while mild or sub-clinical, at which point treatment may be initiated in order to promote continued medical qualification for duty and career retention.

METHODS

We performed a keyword search of PubMed, EMBASE, and Google Scholar along with searches in the NHGRI/EBI GWAS Catalogue and the Atlas of GWAS Summary Statistics. We included primary research from candidate gene, GWAS, and meta-analyses. We also included other review articles in our search to confirm interpretations and implications of any genetic associations with OSA. Only studies related to OSA susceptibility or risk were included.

RESULTS

We identified 134 publications reporting or reviewing genetic associations with OSA risk. These papers reported 301 variants, of which 195 were unique and 33 were replicated in at least two papers. With respect to the strength of association, 43 variants exhibited odds ratios greater than 2. Finally, there were 84 null results reported, 51 of which were in conflict with reported associations.

CONCLUSION

There is ample evidence in the literature to confirm that genetics provide an important contribution to OSA development. The high number of strongly associated variants suggests that a polygenic risk model could be created with high predictive value for prognostic screening.

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

BACKGROUND

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

RESEARCH QUESTION

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

STUDY DESIGN AND METHODS

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

RESULTS

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

INTERPRETATION

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

Efficacy, predictors of success and failure of an updated lateral pharyngoplasty approach as an independent procedure in treating obstructive sleep apnea with CPAP failures

PURPOSE

To assess predictors of success and failure of an updated lateral pharyngoplasty as an independent procedure in treating obstructive sleep apnea with CPAP failures.

METHODS

Forty-six patients with known OSAS who were resistant to CPAP or failures were included. BMI, Stop-Bang score, and sleep study data were recorded before and after the updated Cahali pharyngoplasty procedure. Pre-operative DISE was done for all cases; however, postoperative DISE was done only for non-responders.

RESULTS

Successful operation outcomes achieved in 69.6% (32 cases) and 30.4% (14 cases) were failure rates. Postoperative snoring index, Stop Bang score, and AHI were significantly decreased compared to pre-operative data (p value < 0.001). There is statistically a significant increase in minimal and baseline SpO₂ postoperatively (p value < 0.001). Patients with no laryngeal collapse (L0) predict operation success. However, patients with high pre-operative snoring index, collapse at lateral wall hypopharynx, high tongue collapse, laryngeal collapse, tongue palate interaction, and low grades tonsils (1, 2) predict the failure of the surgery (p value = 0.006*,0.024*,0.047*, respectively).

CONCLUSION

Updated Cahali lateral pharyngoplasty could not be used as an independent procedure in all OSA patients. The lack of laryngeal collapse (L0) is a considerable success predictor for the procedure. However, the pre-operative low-grade tonsils (1, 2) and high snoring index predict operation failure.

Evaluation of Respiratory Resistance as a Predictor for Oral Appliance Treatment Response in Obstructive Sleep Apnea: A Pilot Study

The aim of this study was to determine the utility of respiratory resistance as a predictor of oral appliance (OA) response in obstructive sleep apnea (OSA). Twenty-seven patients with OSA (mean respiratory event index (REI): 17.5 ± 6.5 events/h) were recruited. At baseline, the respiratory resistance (R20) was measured by impulse oscillometry (IOS) with a fitted nasal mask in the supine position, and cephalometric radiographs were obtained to analyze the pharyngeal airway space (SPAS: superior posterior airway space, MAS: middle airway space, IAS: inferior airway space). The R20 and radiographs after the OA treatment were evaluated, and the changes from the baseline were analyzed. A sleep test with OA was carried out using a portable device. The subjects were divided into Responders and Non-responders based on an REI improvement ≥ 50% from the baseline, or REI < 5 after treatment, and the R20 reduction rate between the two groups were compared. The subjects comprised 20 responders and 7 non-responders. The R20 reduction rate with OA in responders was significantly greater than it was in non-responders (14.4 ± 7.9 % versus 2.4 ± 9.8 %, p < 0.05). In responders, SPAS, MAS, and IAS were significantly widened and R20 was significantly decreased with OA (p < 0.05). There was no significant difference in non-responders (p > 0.05). A logistic multiple regression analysis showed that the R20 reduction rate was predictive for OA treatment responses (2% incremental odds ratio (OR), 24.5; 95% CI, 21.5–28.0; p = 0.018). This pilot study confirmed that respiratory resistance may have significant clinical utility in predicting OA treatment responses.

Turkish reliability and validity study of the medical outcomes study (MOS) sleep scale in patients with obstructive sleep apnea

Background/aim

The purpose of the present study was to evaluate the Turkish reliability and validity of the medical outcomes study (MOS) sleep scale in patients who have obstructive sleep apnea.

Materials and methods

The data of the study were collected from 120 adult patients with obstructive sleep apnea and from 90 healthy individuals between March 04 and May 31, 2019.

Results

The Cronbach’s α internal consistency reliability coefficient of the MOS sleep scale was found as 0.82. The test-retest reliability was acceptable (r = 0.76-0.94). Six factors were identified by the factor analysis. These were the same as those in the original MOS-Sleep. The correlations between the MOS-Sleep and other instruments administered in this study provided evidence for structural validity. A significant relation was determined between MOS sleep scale and obstructive sleep apnea syndrome (OSAS) severity and the healthy group ( P < 0.05). In addition, the Cronbach α internal consistency reliability coefficient of the healthy group in MOS sleep scale was found as 0.78. The items of the six factors that were obtained with the confirmatory factor analysis for the MOS sleep scale of the healthy group were found to be the same as in the original MOS-Sleep.

Conclusion

Turkish MOS sleep scale is a measurement tool that consists of 12 items and 6 subdimensions with adequate validity and reliability indicators.

Longer sleep duration may negatively affect renal function

BACKGROUND

Observational studies evaluating the link between sleep duration and kidney function reported controversial results. In the present study, Mendelian randomization analysis was applied to obtain unconfounded estimates of the casual association of genetically determined sleep duration with estimated glomerular filtration rate and the risk of chronic kidney disease.

METHODS

Data from the largest genome-wide association studies on self-reported and accelerometer-derived sleep duration, estimated glomerular filtration rate and chronic kidney disease were analysed in total, as well as separately in diabetic and non-diabetic individuals. Inverse variance weighted (IVW) method, weighted median-based method, MR-Egger and MR-Pleiotropy RESidual Sum and Outlier (MR-PRESSO) were applied, as well as the leave-one-out method to rule out the impact of single single-nucleotide polymorphism.

RESULTS

Individuals with genetically longer self-reported sleep duration had a higher chronic kidney disease risk (IVW: β = 0.358, p = 0.047). Furthermore, in non-diabetics, longer self-reported sleep duration was negatively associated with estimated glomerular filtration rate (IVW: β = - 0.024, p = 0.020). Similarly, accelerometer-derived sleep duration was negatively related to estimated glomerular filtration rate in the total population (IVW: β = - 0.019, p = 0.047) and then on-diabetic individuals. No significant association was found between self-reported sleep duration and estimated glomerular filtration rate in the whole population and type-2 diabetes mellitus patients. None of the estimated associations was subjected to a significant level of heterogeneity. MR-PRESSO analysis did not show any chance of outliers for all estimates. The pleiotropy test also indicated low chance of pleiotropy. The leave-one-out method demonstrated that the links were not driven by single-nucleotide polymorphisms.

CONCLUSIONS

For the first time, the present study shed a light on the potential harmful effects of longer sleep duration (measured both objectively and subjectively) on kidney function. This finding was observed in the total population and in non-diabetic individuals, but not in those with diabetes. Further research is needed to elucidate the links between sleep duration, estimated glomerular filtration rate and the risk of chronic kidney disease.

Risk of mortality among patients with moderate to severe obstructive sleep apnea and diabetes mellitus: results from the SantOSA cohort

INTRODUCTION

Patients with obstructive sleep apnea (OSA) and comorbid diabetes mellitus (DM) are reported to have an increased risk of cardiovascular (CV) outcomes; however, data on CV mortality are scant.

AIM

This study aimed to evaluate if patients with comorbid OSA and DM have an increased risk of CV mortality that is higher than the two diseases in isolation.

METHODS

In this prospective cohort study, we included patients referred for a sleep study with and without DM at baseline. We developed four study groups as follows: group 1 (reference group), OSA (-) DM (-); group 2, OSA (-) DM (+); group 3, OSA (+) DM (-); group 4, OSA (+) DM (+). Intergroup differences were evaluated using the t test and χ² test, and multivariate analysis was performed using logistic regression. The incidence rates of CV mortality were calculated using the Kaplan-Meier (log-rank) model, and adjusted HRs were calculated using the Cox regression model.

RESULTS

A total of 1447 patients were included in the analysis-group 1: 441 participants; group 2: 141 participants; group 3: 736 participants; group 4: 151 participants. The mean follow-up was 5 years. The association between OSA + DM showed an independent risk of incident CV mortality (HR 2.37, CI 1.16-4.82, p = 0.02) and an increased prevalence of coronary heart disease (OR 3.44, CI 1.73-5.59, p < 0.01). In addition, T90% was also associated with CV mortality.

CONCLUSION

The coexistence of OSA + DM was associated with an independent risk of CV mortality. In addition, T90% was also associated with CV mortality.

Three Risk Stratification Tools and Postoperative Pneumonia After Noncardiothoracic Surgery

BACKGROUND

Postoperative in-hospital pneumonia is a serious complication. This study aims to investigate the association between 3 preoperative stratification tools (American Society of Anesthesiologists Physical Status [ASA-PS] score, Charlson Comorbidity Index [CCI], and Rockwood Frailty Deficit Index [FI]) and risk for postoperative pneumonia.

METHODS

We identified adult patients who developed postoperative pneumonia following noncardiothoracic surgery under general anesthesia, between January 1, 2016 and December 31, 2017. Patients with postoperative pneumonia were 1:1 matched to control subjects based on age, sex, and the exact type of operations. Medical records were reviewed to identify variables that may be associated with risk for developing postoperative pneumonia. Analyses adjusted for clinical characteristics were performed using the conditional logistic regression, taking into account 1:1 matched set case-control study design.

RESULTS

We identified 211 cases of postoperative pneumonia, and all 3 tested stratification tools were associated with increased risk: ASA-PS (after all adjustments of American Society of Anesthesiologists (ASA) III, odds ratio 4.17 [95% confidence interval 1.74-10.01]; ASA > III 24.03 [6.54-88.32]), CCI (CCI values > 3, 1.29 [1.02-1.63] per unit CCI score), and frail FI score 3.25 (1.45-7.27). Because of incomplete intake documentation, the FI could not be calculated in 57 (13.5%) patients, but these "unknown frailty" patients were also at increased risk for postoperative pneumonia, 3.15 (1.29-7.72).

DISCUSSION

Three commonly used stratification indices (ASA-PS score, CCI, and FI) were associated with increased risk for postoperative pneumonia. Patients unable to complete intake form to calculate the FI were also at increased risk.

Managing obstructive sleep apnea patients with CPAP failure with a novel Lateral Pharyngoplasty as a stand-alone procedure

BACKGROUND

Obstructive sleep apnea syndrome (OSAS) is caused by a complete or partial obstruction of the upper airway. A new Cahali lateral pharyngoplasty as a stand-alone procedure for the treatment of OSA patients, whatever the level and pattern of airway obstruction in patients with CPAP failure or non-compliant patients, is it?

PATIENTS AND METHODS

40 patients with known OSAS non-compliant with CPAP or CPAP failures included. BMI, Stop-Bang score, and sleep study parameters were reported before and after the new Cahali pharyngoplasty operation. Preoperative DISE was done for all cases.

RESULTS

There were 28 (70%) cases with successful operation outcomes, and 12 (30%) failed cases. Postoperative Stop Bang score, AHI, snoring index were significantly reduced in comparison to preoperative data (p-value <0.001); however, minimal SpO₂ and baseline SpO₂ were significantly increased in comparison to preoperative data. There was a significant improvement in AHI postoperative. Patients collapse at the level of lateral wall hypopharynx, high tongue collapse, laryngeal collapse, tongue palate interaction, all significantly predict failure outcome of the operation (p-value = 0.022). However, the absence of laryngeal collapse (L0) had a successful prediction outcome. The high snoring index significantly predicts operation failure. However, preoperative high baseline SpO₂ predicts operation success significantly.

CONCLUSION

The new Cahali lateral pharyngoplasty can be used as a stand-alone procedure in the absence of lateral wall collapse at the level of the hypopharynx (LH), high tongue base collapse (TH), laryngeal collapse (L1) or tongue palate interaction.

Potential Role of mRNAs and LncRNAs in Chronic Intermittent Hypoxia Exposure-Aggravated Atherosclerosis

Atherosclerosis is the pathological basis of cardiovascular disease. Obstructive sleep apnea (OSA) aggravates atherosclerosis, and chronic intermittent hypoxia (CIH) as a prominent feature of OSA plays an important role during the process of atherosclerosis. The mechanisms of CIH in the development of atherosclerosis remain unclear. In the current study, we used microarray to investigate differentially expressed mRNAs and long non-coding RNAs (lncRNAs) in aorta from five groups of ApoE^–/– mice fed with a high-fat diet and exposed to various conditions: normoxia for 8 weeks, CIH for 8 weeks, normoxia for 12 weeks, CIH for 12 weeks, or CIH for 8 weeks followed by normoxia for 4 weeks. Selected transcripts were validated in aorta tissues and RT-qPCR analysis showed correlation with the microarray data. Gene Ontology analysis and pathway enrichment analysis were performed to explore the mRNA function. Bioinformatic analysis indicated that short-term CIH induced up-regulated mRNAs involved in inflammatory response. Pathway enrichment analysis of lncRNA co-localized mRNAs and lncRNA co-expressed mRNAs were performed to explore lncRNA functions. The up-regulated mRNAs, lncRNA co-localized mRNAs and lncRNA co-expressed mRNAs were significantly associated with protein processing in endoplasmic reticulum pathway in atherosclerotic vascular tissue with long-term CIH exposure, suggesting that differentially expressed mRNAs and lncRNAs play important roles in this pathway. Moreover, a mRNA-lncRNA co-expression network with 380 lncRNAs, 508 mRNAs and 3238 relationships was constructed based on the correlation analysis between the differentially expressed mRNAs and lncRNAs. In summary, our study provided a systematic perspective on the potential function of mRNAs and lncRNAs in CIH-aggravated atherosclerosis, and may provide novel molecular candidates for future investigation on atherosclerosis exposed to CIH.

Efficacy of Oral Appliance Therapy as a First-Line Treatment for Moderate or Severe Obstructive Sleep Apnea: A Korean Prospective Multicenter Observational Study

BACKGROUND AND PURPOSE

Responses to oral appliances (OAs) in obstructive sleep apnea (OSA) vary, and have not been fully evaluated in Korean patients. In this study we aimed to determine the efficacy of OAs for the first-line treatment of Korean patients with moderate or severe OSA.

METHODS

This multicenter prospective observational study included 45 patients with moderate or severe OSA that had been newly diagnosed between March 2017 and May 2018 and who underwent OA treatment for 1 month. Questionnaires were completed and polysomnography (PSG) was performed before and after OA treatment. The primary outcome measures were improvement in the absolute apnea-hypopnea index (AHI) and the percentage reduction in the AHI. The secondary outcomes were improvements in the questionnaire scores related to sleep-associated symptoms and PSG parameters.

RESULTS

The patients were aged 47.4±12.1 years (mean±SD), only two of them were female, and their AHI at baseline was 29.7±10.9/h. After OA treatment the AHI had reduced by 63.9±25.8%, with the reduction was similar between the patients with moderate OSA and those with severe OSA. Overall 31.1% of the patients achieved a normal AHI (<5/h), and 64.4% had an AHI of ≤10/h after the treatment. The body mass index (BMI) was the most reliable factor for predicting the percentage reduction in the AHI. The OAs also improved the sleep architecture and subjective sleep-related symptoms.

CONCLUSIONS

The OAs were effective in patients with moderate or severe OSA. The OAs reduced the mean AHI to 63.9% of the baseline value, and this reduction was influenced by the BMI.

Preoperative cognitive impairment associated with oversedation during recovery from anesthesia

PURPOSE

Our objective was to examine the association between preoperative cognitive status and postoperative recovery from anesthesia.

METHODS

We included patients (70-91 years old) from the Mayo Clinic Study of Aging who received general anesthesia and were admitted to the postanesthesia care unit from January 1, 2010 through April 30, 2018. Procedures were categorized according to patient's preoperative cognitive status: cognitive impaired (CI) and cognitive unimpaired (CU). Perioperative records were reviewed and analyses were performed with generalized estimating equations.

RESULTS

A total of 896 procedures from 611 patients were included, with 203 (22.7%) procedures in the CI group. Compared to CU procedures, CI procedures had higher rates of moderate-deep sedation during anesthesia recovery (52 [25.6%] vs. 103 [14.9%]; odds ratio [OR], 1.91; 95% CI, 1.30-2.80; P  < 0.01), postoperative pulmonary complications (22 [10.8%] vs. 34 [4.9%]; OR, 2.36[1.22-4.54]; P  =  0.01), and postoperative delirium (32 [16.2%] vs. 24 [3.5%]; OR, 5.33 [2.88-9.86]; P  <  0.01). When moderate-deep sedation during anesthesia recovery was a covariate, both CI (OR, 3.02[1.60-5.70]; P  <  0.01) and moderate-deep sedation (OR, 3.94[2.19-7.11]; P  <  0.01) were associated with delirium. In multivariable analysis, postoperative pulmonary complications were associated with moderate-deep sedation (OR, 2.14[1.18-3.87]; P  = 0 .01) but not with CI (OR, 1.49 [0.76-2.92]; P  = 0 .25).

CONCLUSIONS

Cognitive impairment was associated with higher rates of moderate-deep residual sedation during anesthesia recovery and delirium, while moderate-deep sedation was associated with higher rates of pulmonary complications and delirium. We speculate that tailoring the anesthetic to facilitate faster emergence for CI patients could improve complication rates.

Obstructive Sleep Apnea in Acromegaly and the Effect of Treatment: A Systematic Review and Meta-Analysis

BACKGROUND

Obstructive sleep apnea (OSA) is a common disorder characterized by upper airway collapse requiring nocturnal ventilatory assistance. Multiple studies have investigated the relationship between acromegaly and OSA, reporting discordant results.

AIM

To conduct a meta-analysis on the risk for OSA in acromegaly, and in particular to assess the role of disease activity and the effect of treatments.

METHODS AND STUDY SELECTION

A search through literature databases retrieved 21 articles for a total of 24 studies (n = 734). Selected outcomes were OSA prevalence and apnea-hypopnea index (AHI) in studies comparing acromegalic patients with active (ACT) vs inactive (INACT) disease and pretreatment and posttreatment measures. Factors used for moderator and meta-regression analysis included the percentage of patients with severe OSA, patient sex, age, body mass index, levels of insulin-like growth factor 1, disease duration and follow-up, and therapy.

RESULTS

OSA prevalence was similar in patients with acromegaly who had ACT and INACT disease (ES = -0.16; 95% CI, -0.47 to 0.15; number of studies [k] = 10; P = 0.32). In addition, AHI was similar in ACT and INACT acromegaly patients (ES = -0.03; 95% CI, -0.49 to 0.43; k = 6; P = 0.89). When AHI was compared before and after treatment in patients with acromegaly (median follow-up of 6 months), a significant improvement was observed after treatment (ES = -0.36; 95% CI, -0.49 to -0.23; k = 10; P < 0.0001). In moderator analysis, the percentage of patients with severe OSA in the populations significantly influenced the difference in OSA prevalence (P = 0.038) and AHI (P = 0.04) in ACT vs INACT patients.

CONCLUSION

Prevalence of OSA and AHI is similar in ACT and INACT patients in cross-sectional studies. However, when AHI was measured longitudinally before and after treatment, a significant improvement was observed after treatment.

Postoperative nausea and vomiting after bariatric surgery and dexmedetomidine anesthetic: a propensity-weighted analysis

BACKGROUND

Patients undergoing laparoscopic bariatric surgery have high rates of postoperative nausea and vomiting (PONV). Dexmedetomidine based anesthetic could reduce PONV rates.

OBJECTIVES

To determine if PONV rates differ in patients undergoing laparoscopic bariatric surgery with anesthesia primarily based on dexmedetomidine or standard anesthetic management with inhalational agents and opioids.

SETTING

University hospital.

METHODS

From January 2014 to April 2018, 487 patients underwent laparoscopic bariatric surgery and met inclusion criteria (dexmedetomidine, n = 174 and standard anesthetic, n = 313 patients). In both groups, patients received preoperative PONV prophylaxis. We analyzed rates of PONV and moderate-to-deep sedation. A propensity score was calculated and outcomes were assessed using generalized estimating equations with inverse probability of treatment weighting.

RESULTS

Perioperative opioids and volatile anesthetics were reduced in dexmedetomidine patients. During anesthesia recovery the incidence of PONV was similar between dexmedetomidine and standard anesthetic patients (n = 37 [21.3%] versus n = 61 [19.5%], respectively; inverse probability of treatment weighting odds ratio = 1.35; 95% confidence interval .78-2.32, P = .281), and the incidence of sedation higher in dexmedetomidine patients (n = 86 [49.4%] versus n = 75 [24.0%]; inverse probability of treatment weighting odds ratio = 2.43; 95% confidence interval 1.47-4.03, P < 0.001). Rates of PONV and sedation were similar during the remainder of the hospital stay. A secondary sensitivity analysis was performed limited to dexmedetomidine patients who did not receive volatile and results were similar.

CONCLUSIONS

While dexmedetomidine-based anesthesia was associated with reduced opioid and volatile agents use, it was not associated with a reduction of PONV. The higher rates of moderate-to-deep sedation during anesthesia recovery observed with dexmedetomidine may be undesirable in morbidly obese patients.

Eustachian tube dysfunction in candidates for surgery for obstructive sleep apnoea syndrome

Background

Defining the risk factors for Eustachian tube dysfunction can facilitate its prevention. It is hypothesised that Eustachian tube dysfunction as measured by the Eustachian Tube Dysfunction Questionnaire-7 is associated with obstructive sleep apnoea syndrome.

Methods

The questionnaire was systematically translated into Hebrew and validated in the accepted manner. This questionnaire was applied to obstructive sleep apnoea syndrome patients before and after expansion sphincter pharyngoplasty, in pre-set time intervals. The results were compared to those of controls from the general population.

Results

Thirty-one patients (males:females = 19:12) were enrolled in the obstructive sleep apnoea syndrome group. Mean age was 43 years (range, 31–55 years) and mean body mass index was 28 kg/m2 (range, 27–30 kg/m2). Median apnoea-hypopnea index (pre-operatively) was 34 events per hour. The questionnaire scores in expansion sphincter pharyngoplasty candidates were significantly worse than in controls (p < 0.001). Expansion sphincter pharyngoplasty did not change Eustachian tube function in the long term, but was associated with additional self-limiting Eustachian tube dysfunction in the first two post-operative months.

Conclusion

Eustachian tube dysfunction is significantly worse in patients with obstructive sleep apnoea syndrome compared to controls. Expansion sphincter pharyngoplasty is not associated with Eustachian tube function improvement.

Outcome predictors for non-resective pharyngoplasty alone or as a part of multilevel surgery, in obstructive sleep apnea-hypopnea syndrome

PURPOSE

Non-resective pharyngoplasty techniques have been shown to be effective to treat oropharyngeal collapse in patients affected by obstructive sleep apnea-hypopnea syndrome (OSAHS). The aim of our study is to evaluate outcome predictors in a cohort of patients affected by OSAHS and treated with non-resective pharyngoplasty, including variation of pharyngeal measures at the end of the surgical procedure.

METHODS

A cohort of patients affected by OSAHS, with palatal or lateral pharyngeal wall collapse, who underwent non-resective pharyngoplasty, were enrolled between 2014 and 2017. Surgical procedures encompassed non-resective pharyngoplasty by expansion sphincter pharyngoplasty (ESP) or barbed antero-lateral pharyngoplasty with barbed reposition pharyngoplasty (BRP) or barbed suspension pharyngoplasty (BSP) techniques, eventually associated with nasal surgery. Pharyngeal measures were recorded intraoperatively and their variation at the end of the procedure was considered. Surgical success was evaluated at least 6 months after surgery with respiratory polygraphy and ESS questionnaire. Outcome predictors were examined by multivariable logistic regression and ROC curve analysis.

RESULTS

Seventy patients met the study inclusion criteria. ESP, BRP, and BSP in a uni-/multilevel setting led to significant improvement of all respiratory polygraphic parameters and daily sleepiness (p < 0.0001). Outcome analysis showed that greater variation of antero-posterior pharyngeal measure was associated with success (p = 0.01), with an optimal cutoff value of 8.5 mm; low AHI_pre, high ESS_pre, and antero-lateral pharyngoplasty with barbed sutures were associated with a higher rate of cure (p < 0.05).

CONCLUSIONS

Non-resective pharyngoplasty is effective in treating OSAHS patients affected by palatal or lateral pharyngeal wall collapse, and intraoperative variation of antero-posterior width may be a useful tool to predict surgical success.

Differences in patients derived from otolaryngology and other specialties with sleep apnea

Background

Snoring is a main concern in patients who consult an otolaryngologist (ENT physicians) and patients who have cardiovascular comorbidities or excessive daytime sleepiness who usually consult with other specialists. The aim of this study was to describe the clinical differences in patients with obstructive sleep apnea (OSA) referred from ENT or other specialists.

Methods

A prospective study was carried out between June 2015 and July 2018 in a tertiary center. We included patients with suspected OSA referred by the Home Sleep Apnea Test (HSAT) from different specialties such as ENT or other specialties. The main outcome measures of our study were demographic characteristics, clinical characteristics, sleep questionnaire results and HSAT results between OSA patients referred from ENT or other specialists. We used a t-test and chi-squared test for analysis. The diagnostic accuracy of the sleep questionnaires was achieved using receiver operating characteristic (ROC) curve and the area under the curve (AUC).

Results

A total of 481 patients were included. OSA was occurred in 82.4% of the subjects (90 in ENT and 306 in other specialties). Patients with OSA referred from other specialists were older than ENT patients (55 ± 13 vs 44 ± 12; p < 0.001), there was more obesity (IMC 31 ± 5.0 vs 28.7 ± 3.8; p < 0,001), a larger neck circumference (42.2 cm ± 3.7 vs 40.6 cm ± 3.0; p < 0.001) and more reported comorbidities (p < 0.001). ENT patients reported mild OSA (46% vs 31%, p = 0.015) and more positional apnea (62% vs 39%, p = 0.002). In this group, the STOP-BANG questionnaire showed an AUC 0.695 vs AUC 0.804, and for sensitivity, the best cutoff was 4 points.

Patients referred from otorhinolaryngology are different from those referred from other specialties. Clinical evaluation and screening of OSA should be patient-centered according to these clinical findings.

Postoperative Corneal Injuries: Incidence and Risk Factors

BACKGROUND

Previous studies of postoperative corneal injury rates relied on provider-initiated incident reports, which may underestimate the true incidence. Postoperative administration of proparacaine eye drops is used almost exclusively to diagnose corneal injury; therefore, identifying instances of administration may provide a better estimate of corneal injuries. We compared proparacaine administration versus provider-initiated reports to determine rates of corneal injury. In addition, potential associations between clinical variables and injury were assessed with a matched case-control study.

METHODS

The health records of 132,511 sequential adult postanesthesia recovery room admissions (January 1, 2011 to June 30, 2017) were reviewed to identify postoperative proparacaine administration and incident reports of corneal injury. Patients with corneal injury were matched with control patients at a 1:2 ratio to assess factors associated with injury.

RESULTS

Proparacaine drops were administered to 442 patients (425 patients received proparacaine for diagnosis and 17 patients received proparacaine for unrelated reasons). Incident reports identified 320 injuries, and the aggregate corneal injury count was 436 (incidence, 3.3 injuries [95% confidence interval {CI}, 3.0-3.6] per 1000 cases of general anesthesia). Proparacaine administration had a greater case ascertainment percentage than incident reporting (97.5% vs 73.4%; P < .001). The matched case-control analysis found greater risks associated with longer duration of anesthesia (odds ratio, 1.05 [95% CI, 1.03-1.07] per 10 minutes of anesthesia; P < .001) and nonsupine surgical position (odds ratio, 3.89 [95% CI, 2.17-6.98]; P < .001). Patients with injuries also had more evidence of sedation and agitation during anesthesia recovery.

CONCLUSIONS

Calculation of incidence by using the administration of a medication (proparacaine eye drops) that is almost exclusively used to diagnose a specific injury (corneal injury) showed higher case ascertainment percentage than incident-reporting methods. Similar strategies could be used to monitor the rates of other adverse events.

The Efficacy of Device Designs (Mono-block or Bi-block) in Oral Appliance Therapy for Obstructive Sleep Apnea Patients: A Systematic Review and Meta-Analysis

Oral appliance (OA_m) therapy has demonstrated efficacy in treating obstructive sleep apnea (OSA). The aim of this systematic review was to clarify the efficacy of device designs (Mono-block or Bi-block) in OA_m therapy for OSA patients. We performed a meta-analysis using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system. Two studies (Mono-block OA_m versus Bi-block OA_m) remained eligible after applying the exclusion criteria. When comparing Mono-block OA_m and Bi-block OA_m, Mono-block OA_m significantly reduced the apnea-hypopnea index (2.92; 95% confidence interval (95%CI), 1.26 to 4.58; p = 0.0006), and patient preference for Mono-block OA_m was significantly higher (2.06; 95%CI, 1.44 to 2.06; p < 0.0001). Lowest SpO₂, arousal index, non-REM stage 3, sleep efficiency, Epworth Sleepiness Scale (ESS), Snoring Scale, and side effects were not significantly different between the two groups (lowest SpO₂: -11.18; 95%CI, -26.90 to 4.54; p = 0.16, arousal index: 4.40; 95%CI, -6.00 to 14.80; p = 0.41, non-REM stage 3: -2.00; 95%CI, -6.00 to 14.80; p = 0.41, sleep efficiency: -1.42, 95%CI, -4.71 to 1.86; p = 0.40, ESS: 0.12; 95%CI, -1.55 to 1.79; p = 0.89, Snoring Scale: 0.55; 95%CI, -0.73 to 1.83, p = 0.55, side effects: 1.00, 95%CI, 0.62 to 1.61, p = 1.00). In this systematic review, the use of Mono-block OA_m was more effective than Bi-block OA_m for OSA patients.

Effect of the duration of protease inhibitor therapy in HIV-infected individuals on the severity of obstructive sleep apnea

Background

Protease inhibitors (PIs) are a vital part of the antiretroviral therapy. Long-term use of PIs may cause lipodystrophy, a clinical syndrome characterized by peripheral lipoatrophy and central fat accumulation, which may increase the risk of developing obstructive sleep apnea (OSA) in HIV-infected patients. We hypothesize that a longer duration of PIs' use might be associated with increasing severity of OSA in HIV-infected patients.

Materials and Methods

This was a retrospective cohort study of HIV-infected patients who were treated with PIs, who presented with symptoms suggestive of OSA, and underwent nocturnal polysomnography. The primary objective of the study is to evaluate the association between the duration of PIs' use and the severity of OSA. The duration of PIs' use measured in months was recorded for each patient. The primary outcome of interest was the apnea-hypopnea index (AHI) obtained at the time of the sleep study. Data were analyzed using univariate and multivariate linear regression between AHIs with PIs' use as well as other predictors.

Results

A total of 54 patients diagnosed with HIV and OSA were included in the study cohort for the analysis. Sleep study body mass index (BMI; P = 0.042) and change in BMI (ΔBMI; P = 0.027) were the only statistically significant independent predictors of AHI. The association between AHI and PIs' use duration was found to be nonlinear and nonsignificant. Gender differences evaluation suggested possible duration-related effect relationship between PIs and OSA severity among HIV-infected men exposed to PIs within a 66-month duration.

Conclusion

We did not observe a significant association between PIs' use duration and the severity of OSA.

Systematic review of the different aspects of primary snoring

Primary snoring, also known as simple or non-apnoeic snoring, is regarded as the first stage of sleep disordered breathing without severe medical consequences for the snorer and co-sleeper. Although it is a highly prevalent phenomenon in the general population, our knowledge is limited because of the lack of a consensus on terminology. This systematic review of the aspects used in the definitions of simple/primary snoring was conducted to obtain an inventory of current practices and compare these definitions with the conceptual definition of the American Academy of Sleep Medicine. PubMed and Web of Science were searched from July 2016 onwards without any language limitations, and 362 references were obtained. After selection based on titles, 39 remained, among which 29 contained a definition or reference to a definition. In 69% of the studies, a cut-off <5 apnoea/Hypopnoea events per hour of sleep on the Apnoea-Hypopnoea Index was used. Despite this tendency, the cut-offs ranged from 0 to <15/h. Unfortunately, the cut-off and occasional requirements did not match the conceptual definition of the American Academy of Sleep Medicine. A consensus must be reached on an operational and clinically relevant definition based on the clear conceptual definition.

Pattern and severity of sleep apnea in a Saudi sleep center: The impact of obesity

AIM:

The aim of this study was to estimate the effect of obesity on the severity of obstructive sleep apnea (OSA) by assessing the relationship between OSA and body mass index (BMI).

MATERIALS AND METHODS:

A cross-sectional study was conducted in 2017 among patients who had been referred to the sleep center at King Abdulaziz University Hospital (KAUH, Jeddah, Saudi Arabia) for polysomnography between January 2012 and September 2017. The data were abstracted from the medical records of these patients at KAUH. Initial data analysis included descriptive statistics; Chi-square test, t-test, and one-way ANOVA as appropriate were used to assess the associations between the variables.

RESULTS:

The study included 803 patients; the average age of the patients was 45.9 years and 56.5% were male. About 70.4% were obese, 54% of whom were classified as having Class 3 obesity. Approximately, 75% patients had OSA. The prevalence of OSA was higher among obese patients (77.7%) compared to nonobese patients (22.3%). Moreover, the severity of OSA was higher in obese patients, with 85.3% of obese patients considered as having severe OSA.

CONCLUSION:

Obesity is a considerable risk factor for developing OSA and could play a major role in increasing the severity of the disease. We encourage further studies on the impact of sedentary lifestyle and its association with OSA in Saudi Arabia, with an emphasis on the evaluation of the cost-effectiveness and burden of the disease.

Low serum bilirubin levels associated with subclinical atherosclerosis in patients with obstructive sleep apnea

Background

Obstructive sleep apnea (OSA) is a chronic, progressive disease that can cause cardiovascular complications and atherosclerosis. We evaluated the relationship between serum bilirubin levels and carotid intima-media thickness (cIMT), as a surrogate marker of subclinical atherosclerosis, in patients with OSA.

Methods

We enrolled 84 consecutive patients with OSA. The patients underwent ultrasonography, polysomnography, and echocardiography. Blood samples were obtained from all of the subjects, which were used for biochemical comparisons. The patients were divided into groups according to cIMT values (<0.9 vs. >0.9 mm).

Results

The patient population consisted of 84 OSA patients (mean age: 54.2 + 8.0 years, 62.9% male). The OSA patients with cIMT ≥0.9 had significantly elevated high-sensitive C-reactive protein (hsCRP), Oxygen desaturation index, apnea-hypopnea index (AHI), and significantly lower total and indirect bilirubin levels. Multivariate regression analyses revealed that total bilirubin, hsCRP, and AHI were the independent predictors of subclinical atherosclerosis. There was a negative correlation between total bilirubin and cIMT.

Conclusions

This study showed that high hsCRP and low serum total bilirubin levels could be paving the way for the development of subclinical atherosclerosis. Simple measures such as total bilirubin may provide predictive information regarding the risk of cardiovascular disease in patients with OSA.

Anesthetic Management for Medialization Laryngoplasty Performed Under Concurrent Dexmedetomidine, Remifentanil, and Propofol Infusions

INTRODUCTION

Type I thyroplasty, or medialization larygoplasty (ML), is a procedure which improves the voice by medializing a vocal fold with a permanent implant. Anesthetic management of these cases is challenging because patients can require periods of deep sedation followed by fully awake moments for phonation to assess the implant size. We present our experience of ML with or without arytenoid adduction (AA) using a multimodal anesthetic regimen consisting of concurrent infusions of dexmedetomidine, remifentanil, and propofol.

METHODS

This is a retrospective case series of patients anesthetized using this protocol from June 1, 2015 through June 30, 2017.

RESULTS

Seventy-five consecutive ML with or without AA patients anesthetized with dexmedetomidine and remifentanil infusions were identified, of which 74 (98.7%) also received concurrent propofol infusions. Mean duration of sedation was 190.9 ± 36.9 minutes and surgery was 139 ± 35.3 minutes. Transient hypopnea treated with supplemental oxygen complicated 18 (24%) cases and bradycardia requiring pharmacologic treatment complicated 3 (4%) cases. There were no other adverse anesthetic complications. One patient required surgical re-exploration due to postsurgical bleeding after the initial hospital discharge.

CONCLUSION

In this cohort, a combination of remifentanil, dexmedetomidine and propofol infusions was well tolerated without serious adverse perioperative events.

Simulated intention-to-treat analysis based on clinical parameters of patients at high risk for sleep apnea derivated to respiratory polygraphy

Purpose

Obstructive Sleep Apnea-Hypopnea Syndrome (OSAS) is a public health problem. We designed a pilot study to validate empiric indication of CPAP therapy in a population with moderate-to-high pre-test probabilities who underwent self-administered home-based respiratory polygraphy (RP).

Methods

A cross-sectional simulation study was performed. CPAP therapy could be indicated by two independent blind observers. Observer 1´s decision was based on the results of STOP-BANG (SBQ) and Epworth Sleepiness Scale (ESS) and Observer 2 used all objective data provided by RP + SBQ + ESS.

Results

We evaluated 1763 patients; 1060 men and 703 women (39.2%) with a mean age of 53.6±13.8 and a body mass index (BMI) of 32.8±7.5 kg/m2. We found evidence of mild (34.1%), moderate (26.6%), and severe (18.3%) There were Apnea-Hypopnea Index (AHI) relationship between > 5 or < 5 SBQ and RP AHI (p<0.05). BMI > 25 kg/m² + snoring (S) + observed apnea (O) + 1 of the following: ESS > 11, hypertension (HT) or > 5 SBQ components showed sensitivity of 40% (CI95%: 37.3-43) and specificity of 95.1% (CI93.4-96.4). The performance of 5 SBQ components with regard to gender and empirical CPAP therapy was; (women vs. men): AUC-ROC 0.625 (CI95%: 0.599-0.651) vs. 0.70 (CI95%: 0.68-0.72), p<0.01, respectively.

Conclusions

STOP-BANG and ESS made it possible to indicate CPAP reliably (low rate of false-positive results) in 20-40% of patients who needed such therapy according to clinical history and RP results. These clinical criteria performed better in male.

Obstructive sleep apnoea and increased risk of non-arteritic anterior ischaemic optic neuropathy

BACKGROUND/AIMS

To determine whether the development of non-arteritic anterior ischaemic optic neuropathy (NAION) is increased among patients newly diagnosed with obstructive sleep apnoea (OSA) in a large general population.

METHODS

A 12-year nationwide, population-based, retrospective cohort study including 1 025 340 beneficiaries in the 2002-2013 Korean National Health Insurance Service database was performed. We identified 919 patients newly diagnosed with OSA aged ≥40 years and matched 9190 non-OSA controls using estimated propensity scores in reference to age, sex, demographics, comorbidities and co-medications. We applied Kaplan-Meier curves and Cox proportional hazard models to determine the risk of developing NAION in the OSA group compared with the non-OSA group.

RESULTS

The 10-year incidence probability of NAION was higher in the OSA group (0.92%; 95% CI 0.88 to 0.97) than the non-OSA group (0.42%; 95% CI 0.41 to 0.44, p=0.002, log-rank test). The OSA group was at increased risk of developing NAION compared with the non-OSA group (HR 3.80; 95% CI 1.46 to 9.90) after adjusting for demographics, comorbidities and co-medications.

CONCLUSIONS

Our results suggest that patients with newly diagnosed OSA have an increased risk of NAION, although the absolute risk of NAION is low.

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.

Dental and skeletal changes associated with long-term oral appliance use for obstructive sleep apnea: A systematic review and meta-analysis

An oral appliance (OA) is an effective treatment option for patients with obstructive sleep apnea (OSA), but dental and skeletal changes have been detected by many studies after long-term OA use. Better understanding of the long-term side effects may decrease discontinuation of OA use and assist clinicians to make informed decisions. Accordingly, a systematic review and meta-analysis were performed to evaluate the dental and skeletal changes associated with OAs designed to advance the mandible. The quality of the studies was determined by using the risk of bias assessment tool for non-randomized studies (RoBANS), and 12 studies were included in the meta-analysis. OA use was associated with a significant decrease of overjet (OJ) and overbite (OB), and it was suggested that both parameters decreased along with the duration of treatment. Meta-analysis also demonstrated a significant increase of L1-MP. However, there were no significant changes of skeletal modifications or mandibular rotation. Changes of incisor inclination were suggested to make a contribution to reduction of OJ and OB. In conclusion, long-term OA use was associated with dental changes. The results of this study provide information for clinicians about the long-term effects of OAs.