A comparison of polysomnography and the WatchPAT in the diagnosis of obstructive sleep apnea

Nocturia and obstructive sleep apnoea

Nocturia, the need to urinate at night, is a common symptom in patients with obstructive sleep apnoea (OSA). Continuous positive airway pressure treatment can reduce nocturia in some patients, but the underlying mechanisms are complex and not fully understood. OSA affects the autonomic nervous system, oxidative stress and endothelial damage. Furthermore, the commonly held theory attributing polyuria to a false signal of cardiac overload and response natriuresis has limitations. A comprehensive approach to the management of nocturia in OSA, considering factors such as comorbidities, medication use, alcohol consumption and lifestyle, is needed. Effective management of nocturia in OSA requires a multidisciplinary approach, and urologists should be aware of the potential effect of OSA on physiology and refer patients for further testing at a sleep centre. In addition to continuous positive airway pressure, other interventions such as oral appliances and surgical obstruction treatment could be beneficial for some patients. Overall, understanding the complex interplay between OSA and nocturia is crucial for optimizing patient outcomes.

Restless legs syndrome, periodic limb movements of sleep, and subclinical cardiovascular disease

Restless legs syndrome (RLS) and periodic limb movements of sleep (PLMS) have been variably implicated in risk for cardiovascular disease (CVD), but there is lack of consensus on these relationships. We sought to assess subclinical CVD measures and RLS/PLMS in a large cohort to further evaluate these associations. The Emory Center for Health Discovery and Well Being cohort is composed of employed adults, with subclinical CVD measures including endothelial function (flow-mediated vasodilation), microvascular function (reactive hyperemia index, RHI), arterial stiffness (pulse wave velocity and augmentation index), and carotid intima-media thickness (cIMT). Participants were grouped based on presence (N = 50) or absence (N = 376) of RLS and subclinical CVD measures compared between groups. A subset of participants (n = 40) underwent ambulatory monitoring for PLMS and obstructive sleep apnea. PLMS association with subclinical CVD measures was assessed. RLS status was significantly associated with flow-mediated dilation in univariate analyses but not after controlling for potential confounders; RLS was not associated with other subclinical CVD measures. PLMS were significantly correlated with the RHI, augmentation index, and cIMT in univariate analyses; only the association between PLMS and cIMT remained significant (p = 0.04) after controlling for RLS status, age, apnea-hypopnea index, hyperlipidemia, and hypertension. The observed association between higher PLMS and greater cIMT suggests that PLMS may be a marker of subclinical CVD. Further work is needed to determine the relationship between PLMS and CVD risk.

Supplementary Information

The online version contains supplementary material available at 10.1007/s41105-023-00497-7.

The Positive Impact of Bariatric Surgery on Vascular Health

BACKGROUND

Obesity is one of the most prevalent medical conditions in the Western world. There are many risk factors associated with obesity, including cardiovascular and pulmonary risk. Vascular health is not studied in obese patients, and whether obesity has an adverse effect on vascular health in these patients remains unknown.

OBJECTIVE

The first objective is to find a correlation between vascular health and obesity and whether obesity can be classified as a risk factor for vascular health. The second objective is to see if weight loss leads to an improvement in vascular health in patients.

METHODS

The study was conducted with pre- and post-surgical methods at Baylor Scott & White (BSWH) Medical Center, Temple, Texas, USA. Ten patients were approached, consented, and prepared to obtain baseline values through WatchPAT and EndoPAT devices prior to their bariatric surgery. Values obtained include their initial weight, respiratory disturbance index, apnea-hypopnea index, oxygen desaturation index, and degree of endothelial dysfunction via the EndoPAT device. Post-surgery, these values were obtained again and compared using Wilcoxon non-parametric analyses with a level of significance at p < 0.05.

RESULTS

Our study results demonstrate a correlation between obesity and vascular health as endothelial dysfunction is widely seen. In our patients, after bariatric surgery, we saw a significant weight change (31.2% +11.2, p < 0.0001). There was a significant degree of endothelial function improvement after the weight loss (31.2% +34.7, p < 0.04).

CONCLUSION

Our results indicate that there is a correlation between obesity and vascular health, which also correlates with cardiovascular risk. There is a significant reduction in endothelial dysfunction after weight loss. We believe that obesity is a risk factor for vascular health outcomes.

Characterization of sleep apnea among a sample of adults from Samoa

Sleep apnea is a public health concern around the world, but little research has been dedicated to examining this issue in low- and middle-income countries, including Samoa. Using data collected through the Soifua Manuia ("Good Health") study, which aimed to investigate the impact of the body mass index (BMI)-associated genetic variant rs373863828 in CREB3 Regulatory Factor ( CREBRF ) on metabolic traits in Samoan adults, we examined the sample prevalence and characteristics of sleep apnea using data collected with a validated home sleep apnea device (WatchPAT, Itamar). A total of 330 participants (sampled to overrepresent the obesity-risk allele of interest) had sleep data available. Participants (53.3% female) had a mean (SD) age of 52.0 (9.9) years and BMI of 35.5 (7.5) kg/m 2 and 36.3% of the sample had type 2 diabetes. Based on the 3% and 4% apnea hypopnea indices (AHI) and the 4% oxygen desaturation index (ODI), descriptive analyses revealed that many participants had potentially actionable sleep apnea defined as >5 events/hr (87.9%, 68.5%, and 71.2%, respectively) or clinically actionable sleep apnea defined as ≥15 events/hr (54.9%, 31.5%, and 34.5%, respectively). Sleep apnea was more severe in men; for example, clinically actionable sleep apnea (≥15) based on the AHI 3% definition was observed in 61.7% of men and 48.9% of women. Correction for non-representational sampling related to the CREBRF obesity-risk allele resulted in only slightly lower estimates. Across the AHI 3%, AHI 4%, and ODI 4%, multiple linear regression revealed associations between a greater number of events/hr and higher age, male sex, higher body mass index, higher abdominal-hip circumference ratio, and geographic region of residence. Our study identified a much higher frequency of sleep apnea in Samoa compared with published data from other studies, but similar predictors. Continued research addressing generalizability of these findings, as well as a specific focus on diagnosis and affordable and equitable access to treatment, is needed to alleviate the burden of sleep apnea in Samoa and around the world.

Evaluating an under-mattress sleep monitor compared to a peripheral arterial tonometry home sleep apnea test device in the diagnosis of obstructive sleep apnea

STUDY OBJECTIVES

To evaluate whether or not the apnea-hypopnea index (AHI) from a peripheral arterial tonometry (PAT) home sleep apnea test (HSAT) is equivalent to the AHI provided by the mean of one, three, or seven nights from the Withings Sleep Analyzer (WSA) under-mattress device.

METHODS

We prospectively enrolled patients with suspected OSA in whom a PAT-HSAT was ordered. Eligible patients used the WSA for seven to nine nights. PAT data were scored using the device's intrinsic machine learning algorithms to arrive at the AHI using both 3% and 4% desaturation criteria for hypopnea estimations (PAT3%-AHI and PAT4%-AHI, respectively). These were then compared with the WSA-estimated AHI (WSA-AHI).

RESULTS

Of 61 patients enrolled, 35 completed the study with valid PAT and WSA data. Of the 35 completers 16 (46%) had at least moderately severe OSA (PAT3%-AHI ≥ 15). The seven-night mean WSA-AHI was 2.13 (95%CI =  - 0.88, 5.14) less than the PAT3%-AHI, but 5.64 (95%CI = 2.54, 8.73) greater than the PAT4%-AHI. The accuracy and area under the receiver operating curve (AUC) using the PAT3%-AHI ≥ 15 were 77% and 0.87 and for PAT4%-AHI ≥ 15 were 77% and 0.85, respectively. The one-, three-, or seven-night WSA-AHI were not equivalent to either the 3% or 4% PAT-AHI (equivalency threshold of ± 2.5 using the two one-sided t-test method).

CONCLUSIONS

The WSA derives estimates of the AHI unobtrusively over many nights, which may prove to be a valuable clinical tool. However, the WSA-AHI over- or underestimates the PAT-AHI in clinical use, and the appropriate use of the WSA in clinical practice will require further evaluation.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04778748.

International Consensus Statement on Obstructive Sleep Apnea

BACKGROUND

Evaluation and interpretation of the literature on obstructive sleep apnea (OSA) allows for consolidation and determination of the key factors important for clinical management of the adult OSA patient. Toward this goal, an international collaborative of multidisciplinary experts in sleep apnea evaluation and treatment have produced the International Consensus statement on Obstructive Sleep Apnea (ICS:OSA).

METHODS

Using previously defined methodology, focal topics in OSA were assigned as literature review (LR), evidence-based review (EBR), or evidence-based review with recommendations (EBR-R) formats. Each topic incorporated the available and relevant evidence which was summarized and graded on study quality. Each topic and section underwent iterative review and the ICS:OSA was created and reviewed by all authors for consensus.

RESULTS

The ICS:OSA addresses OSA syndrome definitions, pathophysiology, epidemiology, risk factors for disease, screening methods, diagnostic testing types, multiple treatment modalities, and effects of OSA treatment on multiple OSA-associated comorbidities. Specific focus on outcomes with positive airway pressure (PAP) and surgical treatments were evaluated.

CONCLUSION

This review of the literature consolidates the available knowledge and identifies the limitations of the current evidence on OSA. This effort aims to create a resource for OSA evidence-based practice and identify future research needs. Knowledge gaps and research opportunities include improving the metrics of OSA disease, determining the optimal OSA screening paradigms, developing strategies for PAP adherence and longitudinal care, enhancing selection of PAP alternatives and surgery, understanding health risk outcomes, and translating evidence into individualized approaches to therapy.

Assessment of Perioperative Sleep Characteristics Using Subjective and Objective Methods: A Secondary Analysis of Prospective Cohort Study

Perioperative sleep disturbances may impact healing and negatively affect the patient's perception of well-being. Therefore, accurately assessing postoperative sleep characteristics is necessary to treat sleep disturbances. This study is a secondary data analysis of research investigating the association between sleep and cognition in a perioperative setting. This study compares sleep characteristics between the St. Mary's Hospital Sleep Questionnaire and WatchPAT, a portable sleep apnea testing device. The goal of this study is to compare an objective measurement of sleep quality (WatchPAT) with a traditional questionnaire. One hundred and one patients who underwent elective, noncardiac surgical procedures wore a WatchPAT and completed the St. Mary's Hospital Sleep Questionnaire for three nights: two preoperative and one postoperative night. In the preoperative period, a Bland-Altman analysis showed an agreement Watch PAT and the St Mary's hospital sleep questionnaire except for sleep fragmentation. A good to fair correlation during the preoperative period was observed with both sleep latency and total sleep time. In the postoperative period, no correlation was observed between the St. Mary's Hospital Sleep Questionnaire data and WatchPAT data. Our study indicates that some potential factors affecting sleep and cognition such as admission type, depression, anesthesia type, and sleep apnea may limit patients' ability to report their sleep characteristics after surgery. Therefore, relying solely on one sleep assessment method is not advisable.

Evaluation of sleeping parameters with peripheral arterial tonometry in childhood sleep apnea and snoring: a clinical feasibility study

PURPOSE

The influence of adenoidectomy ± tonsillotomy/tonsillectomy on objective sleep parameters in children with Obstructive Sleep Apnea (OSA) was determined with the help of ambulatory polygraphy (WatchPat300^®, Neucomed Ltd., Vienna, Austria). These results were compared with the findings of the OSA-18 questionnaire.

METHODS

27 children treated with adenoidectomy ± tonsillotomy/tonsillectomy at the Department of Otorhinolaryngology, Head and Neck Surgery, Medical University of Innsbruck, were consecutively included in this prospective clinical trial. Pre- and postoperative objective sleeping parameters were assessed with outpatient polygraphy (WatchPat300^®) and subjective symptoms with the OSA-18 questionnaire.

RESULTS

Most of the children presented with severe OSA (41%, 11/27). The mean preoperative AHI was 10.2 (± 7.4). Postoperatively it declined to 3.7 (± 1.8; p < 0.0001). Following surgery 19/24 (79%) children had a mild OSA and 8/24 (21%) a moderate OSA. None of the children suffered from severe OSA anymore after surgery. The postoperative AHI did not correlate with the age (p = 0.3), BMIp (p = 0.6) or extent of surgery (p = 0.9). The mean postoperative OSA-18 survey score was significantly lower than the preoperative one (70.7 ± 26.7 vs. 34.5 ± 10.5; p < 0.0001). The postoperative OSA-18 questionnaire showed a normal survey score below 60 in 23/24 (96%) of the children.

CONCLUSIONS

The WatchPat^® device might be a feasible way for objective assessment of pediatric OSA in children older than 3 years. Adenoidectomy ± tonsillotomy/tonsillectomy caused a significant decrease of the AHI in children with OSA. This effect was especially pronounced in children with severe OSA and none of the children had persistent severe OSA after surgery.

Immediate and Medium-Term Follow-Up of Patients with Obstructive Sleep Apnea Undergoing Pharyngeal and Nasal Surgery: A Pilot Study

Objectives  To evaluate the evolution of obstructive sleep apnea (OSA), comparing data from preoperative, immediate postoperative and late postoperative, in patients undergoing pharyngeal surgery associated with nasal surgery, and to compare the findings of arterial tonometry and type 1 polysomnography in the late postoperative period. Methods  Seventeen adults with moderate or severe OSA were included in the study. They underwent clinical evaluation, surgical intervention, and sleep study preoperatively, on the 1 ^st night after surgery, and after a minimum period of 3 months. The data for the three moments were compared. Results  The mean age was 38.1 ± 12.5 years old (22 to 59 years old), and 82.3% were male. Body mass index (BMI) ranged from 25.6 to 45.1 kg/m2 (mean = 33.1 ± 5.8 kg/m ² ). Fifteen patients (88.2%) were diagnosed with severe OSA. There was a progressive improvement, with a decrease in the indexes (AHI and RDI) and in the percentage of time with peripheral oxyhemoglobin saturation below 90% (tSpO < 90%), and an increase in nadir of SpO2. In the comparison between the 2 methods used in the late postoperative period - arterial tonometry and polysomnography - there was no difference in the indexes and in the tSpO < 90%. Discussion  There was a progressive and favorable impact of pharyngeal surgery on the improvement of polysomnographic and clinical respiratory parameters; however, many patients maintained residual OSA, suggesting the need for a new sleep study in the postoperative period. The arterial tonometry showed similar findings to polysomnography, which can be considered as an option in postoperative follow-up of patients.

Portable evaluation of obstructive sleep apnea in adults: A systematic review

Obstructive sleep apnea (OSA) is a significant healthcare burden affecting approximately one billion people worldwide. The prevalence of OSA is rising with the ongoing obesity epidemic, a key risk factor for its development. While in-laboratory polysomnography (PSG) is the gold standard for diagnosing OSA, it has significant drawbacks that prevent widespread use. Portable devices with different levels of monitoring are available to allow remote assessment for OSA. To better inform clinical practice and research, this comprehensive systematic review evaluated diagnostic performances, study cost and patients' experience of different levels of portable sleep studies (type 2, 3, and 4), as well as wearable devices and non-contact systems, in adults. Despite varying study designs and devices used, portable diagnostic tests are found to be sufficient for initial screening of patients at risk of OSA. Future studies are needed to evaluate cost effectiveness with the incorporation of portable diagnostic tests into the diagnostic pathway for OSA, as well as their application in patients with chronic respiratory diseases and other comorbidities that may affect test performance.

ERS technical standards for using type III devices (limited channel studies) in the diagnosis of sleep disordered breathing in adults and children

For more than three decades, type III devices have been used in the diagnosis of sleep disordered breathing in supervised as well as unsupervised settings. They have satisfactory positive and negative predictive values for detecting obstructive and central sleep apnoea in populations with moderately high pre-test probability of symptoms associated with these events. However, standardisation of commercially available type III devices has never been undertaken and the technical specifications can vary widely. None have been subjected to the same rigorous processes as most other diagnostic modalities in the medical field. Although type III devices do not include acquisition of electroencephalographic signals overnight, the minimum number of physical sensors required to allow for respiratory event scoring using standards outlined by the American Academy of Sleep Medicine remains debatable. This technical standard summarises data on type III studies published since 2007 from multiple perspectives in both adult and paediatric sleep practice. Most importantly, it aims to provide a framework for considering current type III device limitations in the diagnosis of sleep disordered breathing while raising research- and practice-related questions aimed at improving our use of these devices in the present and future.

Detecting sleep apnea in adults with Down syndrome using WatchPAT: A feasibility study

BACKGROUND

In daily practice, sleep apnea is underdiagnosed in people with Down syndrome. The WatchPAT can detect sleep apnea in a less invasive way.

AIM

This study aimed to evaluate the feasibility of the WatchPAT to detect sleep apnea in individuals with Down syndrome.

METHODS AND PROCEDURES

Thirty-one participants with Down syndrome (aged 18+) were included. Sleep apnea was detected with the WatchPAT and compared to results of the STOP-Bang Questionnaire (current practice). Experiences of participants, caregivers and clinicians were studied using a combination of quantitative and qualitative methods.

OUTCOMES AND RESULTS

Among the 68% of participants who accepted the WatchPAT, sleep apnea was detected in 95% of participants. Younger participants and participants with mild/moderate intellectual disabilities were more likely to accept the device. STOP-Bang did not detect most cases of sleep apnea. For the degree of sleep apnea, interrater reliability was substantial (k = 0.71) to almost perfect (k = 0.91). Considering experiences, caregivers and clinicians were predominantly positive about the WatchPAT.

CONCLUSIONS

Our study showed that the WatchPAT is a promising device to detect sleep apnea in people with Down syndrome. Compared to polysomnography, detection with this device is less invasive and less burdensome for people with Down syndrome. Furthermore, the WatchPAT is a relatively accessible solution to implement in care institutions.

Diagnostic accuracy of home sleep apnea testing using peripheral arterial tonometry for sleep apnea: A systematic review and meta-analysis

This study aimed to evaluate the diagnostic accuracy of home sleep apnea testing using peripheral arterial tonometry for sleep apnea as an alternative to polysomnography. We conducted a systematic review and meta-analysis of observational studies, randomized controlled trials, and diagnostic case-control studies examining the diagnostic accuracy of peripheral arterial tonometry by searching the CENTRAL, MEDLINE, EMBASE, ICTRP and ClinicalTrials.gov databases on 5 October 2021. We assessed the risk of bias of the included studies using the Quality Assessment of Diagnostic Accuracy Studies-2 tool. A bivariate random-effects model was generated to derive the summary point estimates of sensitivity and specificity with 95% confidence intervals at different apnea-hypopnea index cutoffs. This meta-analysis included 13 studies (1227 participants, median prevalence of sleep apnea with apnea-hypopnea index ≥ 5 events per hr: 85%). The risk of bias in the included studies was low to moderate. The pooled sensitivity and specificity estimates were 96% (95% confidence interval: 93%-97%) and 44% (95% confidence interval: 32%-56%) at apnea-hypopnea index ≥ 5 events per hr, 88% (85%-91%) and 74% (63%-83%) at apnea-hypopnea index ≧ 15 events per hr, and 80% (66%-89%) and 90% (83%-95%) at apnea-hypopnea index ≧ 30 events per hr, respectively. Peripheral arterial tonometry resulted in a significant number of false negatives and false positives at any apnea-hypopnea index cutoff when applied to the median prevalence setting of the included studies. The inadequate sensitivity and specificity of peripheral arterial tonometry render it an unsuitable alternative to polysomnography for detecting sleep apnea for apnea-hypopnea index ≧ 5, 15 and 30 events per hr.

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.

A meta-analysis of diagnostic test performance of peripheral arterial tonometry studies

STUDY OBJECTIVES

The objective of this meta-analysis was to analyze agreement in apnea-hypopnea index (AHI) determination between peripheral arterial tonometry (PAT) and polysomnography (PSG) studies.

METHODS

Mean AHI bias and standard deviation (SD) extracted from Bland-Altman plots reported in studies was pooled in a meta-analysis, which was then used to calculate percentage errors of limit agreement (PE) in AHI determination by PAT using PSG AHI as the reference. Individual participant data (where reported in studies) was used to compute Cohen's kappa to assess agreement between PSG and PAT on sleep apnea severity and also for computing sensitivity and specificity of PAT at different AHI thresholds using PSG AHI as the reference.

RESULTS

From 17 studies and 1318 participants (all underwent simultaneous PSG and WatchPAT), a pooled mean AHI bias of 0.30 (standard error (SE) 0.74) and a WatchPAT AHI PE of 230% was calculated. Meta-analysis of Cohen's kappa for agreement between PSG and WatchPAT studies for classifying patients with no sleep apnea, mild, moderate or severe sleep apnea severity was 0.45 (SE 0.06), 0.29 (SE 0.05), 0.25 (SE 0.07) and 0.64 (SE 0.05), respectively. At AHI thresholds 5, 15 and 30, WatchPAT studies showed pooled sensitivities and specificities of 94.11% and 43.47%, 92.21% and 72.39% and 74.11% and 87.10%, respectively. Likelihood ratios were not significant at any AHI threshold.

CONCLUSIONS

The results of this meta-analysis suggest clinically significant discordance between WatchPAT and PSG measurements of AHI, significant sleep apnea severity misclassification by PAT studies and also poor diagnostic test performance.

Peripheral arterial tonometry-PAT technology

PAT Technology is a plethysmographic based measurement method which facilitates the accurate recording of the pulsatile volume changes of the arteries of peripheral vascular beds at the distal end of the fingers over sustained periods of time. It represents a departure from previously available plethysmographic methods, in so far as it applies a uniform pressure field which completely envelopes the measured part of a digit, including its distal-most tip. Applying near diastolic blood pressure levels of pressure within the PAT probe optimizes the dynamic range of the signal, prevents confounding veno-arteriolar reflex vasoconstriction at the measurement site, reduces respiratory and movement artifacts and thus facilitates accurate long term measurement. The vascular bed of the distal phalanx of the finger is a major site of sympathetic nervous system mediated vasoconstrictor activity, and the PAT response to sympathetic changes provides a platform for accurate and robust measurement in a number of sleep and sleep related clinical areas, foremost as a patient friendly and extensively validated home sleep testing device.

Self-Applied Home Sleep Recordings: The Future of Sleep Medicine

Sleep disorders form a massive global health burden and there is an increasing need for simple and cost-efficient sleep recording devices. Recent machine learning-based approaches have already achieved scoring accuracy of sleep recordings on par with manual scoring, even with reduced recording montages. Simple and inexpensive monitoring over multiple consecutive nights with automatic analysis could be the answer to overcome the substantial economic burden caused by poor sleep and enable more efficient initial diagnosis, treatment planning, and follow-up monitoring for individuals suffering from sleep disorders.

Sleep apnea is associated with residual kidney function and mortality in patients with peritoneal dialysis: Prospective cohort study

INTRODUCTION

Fluid overload and sleep apnea (SA) are known risk factors for mortality in dialysis patients. Although incidence and severity of SA were shown higher in peritoneal dialysis (PD) patients than in hemodialysis patients, data regarding the association of SA with body fluid status and mortality are limited. Therefore, the association of SA with body fluid status and mortality were investigated in a prospective cohort with patients undergoing PD.

METHODS

The present study included 103 prevalent PD patients who were followed up for median 70 months. At baseline, the subjects underwent in-home polysomnography, bioelectrical impedance analysis, and urea kinetics. Excessive daytime sleepiness and sleep quality were assessed using sleep questionnaires. SA was defined as apnea/hypopnea index higher than 15 events per hour.

RESULTS

Sleep apnea was diagnosed in 57 (55.3%) patients (SA group); the subjects had significantly higher extracellular water (10.3 ± 1.4 vs. 9.2 ± 1.8, p = 0.001) and lower residual kidney function (RKF) (3.3 ± 3.3 vs. 5.9 ± 7.2, p = 0.02) compared with subjects in the non-SA group. SA was significantly associated with RKF [odds ratio, 0.84; 95% confidence interval (CI), 0.73-0.97] in multivariable logistic regression analysis. In multivariable Cox regression models, SA was a significant predictor of mortality in PD patients (adjusted hazard ratio, 5.74; 95% CI, 1.09-30.31) after adjusting for well-known risk factors.

CONCLUSIONS

Sleep apnea was very common in PD patients and significantly associated with lower RKF. SA was also a novel risk predictor of mortality in PD patients.

Performance of peripheral arterial tonometry-based testing for the diagnosis of obstructive sleep apnea in a large sleep clinic cohort

STUDY OBJECTIVES

Peripheral arterial tonometry (PAT)-based technology represents a validated portable monitoring modality for the diagnosis of OSA. We assessed the diagnostic accuracy of PAT-based technology in a large point-of-care cohort of patients studied with concurrent polysomnography (PSG).

METHODS

During study enrollment, all participants suspected to have OSA and tested by in-laboratory PSG underwent concurrent PAT device recordings.

RESULTS

Five hundred concomitant PSG and WatchPat tests were analyzed. Median (interquartile range) PSG AHI was 18 (8-37) events/h and PAT AHI_3% was 25 (12-46) events/h. Average bias was + 4 events/h. Diagnostic concordance was found in 42%, 41%, and 83% of mild, moderate, and severe OSA, respectively (accuracy = 53%). Among patients with PAT diagnoses of moderate or severe OSA, 5% did not have OSA and 19% had mild OSA; in those with mild OSA, PSG showed moderate or severe disease in 20% and no OSA in 30% of patients (accuracy = 69%). On average, using a 3% desaturation threshold, WatchPat overestimated disease prevalence and severity (mean + 4 events/h) and the 4% threshold underestimated disease prevalence and severity by -6 events/h.

CONCLUSIONS

Although there was an overall tendency to overestimate the severity of OSA, a significant percentage of patients had clinically relevant misclassifications. As such, we recommend that patients without OSA or with mild disease assessed by PAT undergo repeat in-laboratory PSG. Optimized clinical pathways are urgently needed to minimize therapeutic decisions instituted in the presence of diagnostic uncertainty.

[Quantification of the loudness of snoring according to Watch-PAT-200 and its relationship with the severity of obstructive sleep apnea syndrome]

PURPOSE OF THE STUDY

Evaluate the capabilities of Watch-PAT-200 in obtaining data to determine the relationship between the loudness of snoring and the severity of obstructive sleep apnea syndrome (OSAS).

MATERIAL AND METHODS

From 2017 to 2019, 208 patients with complaints of nocturnal snoring were examined. Apnea / hypopnea indices (AHI) and respiratory distress index (RDI) were assessed. The study was carried out on a Watch-PAT-200 portable device (Itamar Medical, Israel). The average volume of snoring (dB) and the proportion (%) of sleep time with the intensity of snoring over 50.60 and 70 dB were measured. The correlation of the obtained data with the AHI and RDI indices is estimated.

RESULTS

During the study, it was found that the volume of snoring increases as the severity of OSAS increases, therefore, the volume of snoring can be an indicator of the severity of OSAS. There are ample opportunities for screening diagnostics of the loudness of snoring with the subsequent consultation of a somnologist and timely prescription of treatment. Due to the objectivity of the obtained data and ease of use, the Watch-PAT-200 device can be used in outpatient practice for screening diagnostics of snoring and OSAS in the population.

Objective sleep measures after endoscopic sinus surgery in patients with chronic rhinosinusitis

BACKGROUND

Poor sleep quality is common in chronic rhinosinusitis (CRS). Prior studies have demonstrated improvements in patient-reported measures of sleep quality following endoscopic sinus surgery (ESS). The purpose of this study was to evaluate the effect of ESS on objective sleep parameters and identify any associations between specific objective measures and patient characteristics, comorbidities, and patient-reported outcome measures (PROMs).

METHODS

Adults with CRS undergoing ESS were prospectively enrolled from 4 centers across North America. Any subject previously diagnosed with a known primary sleep disorder was excluded. Objective sleep indices were recorded using a portable sleep diagnostic device preoperatively and postoperatively. Patient-reported outcome instruments were completed including the Pittsburgh Sleep Quality Index (PSQI) and the 22-item Sino-Nasal Outcome Test (SNOT-22).

RESULTS

Thirty-six patients (mean age 47 years, 56% male) completed baseline and postoperative sleep studies with mean ± standard deviation (SD) follow-up 9.6 ± 7.7 months. Mean PSQI and SNOT-22 before and after ESS was 10.2 ± 3.9 vs 7.8 ± 4.4 (p = 0.001); and 54.6 ± 14.6 vs 28.5 ± 15.3 (p < 0.001), respectively. Total sleep time, sleep latency, and awakenings after sleep onset did not change following ESS (all p > 0.5) despite improvements in PSQI and SNOT-22. Changes in PSQI did not correlate with comorbidities or objective sleep indices (all p > 0.1).

CONCLUSION

In this multicenter prospective cohort, objective sleep indices were not improved following ESS for CRS despite significant improvements in patient-reported sleep quality and CRS-specific QOL.

Improving the performance of peripheral arterial tonometry-based testing for the diagnosis of obstructive sleep apnea

Outside sleep laboratory settings, peripheral arterial tonometry (PAT, eg, WatchPat) represents a validated modality for diagnosing obstructive sleep apnea (OSA). We have shown before that the accuracy of home sleep apnea testing by WatchPat 200 devices in diagnosing OSA is suboptimal (50%-70%). In order to improve its diagnostic performance, we built several models that predict the main functional parameter of polysomnography (PSG), Apnea Hypopnea Index (AHI). Participants were recruited in our Sleep Center and underwent concurrent in-laboratory PSG and PAT recordings. Statistical models were then developed to predict AHI by using robust functional parameters from PAT-based testing, in concert with available demographic and anthropometric data, and their performance was confirmed in a random validation subgroup of the cohort. Five hundred synchronous PSG and WatchPat sets were analyzed. Mean diagnostic accuracy of PAT was improved to 67%, 81% and 85% in mild, moderate-severe or no OSA, respectively, by several models that included participants' age, gender, neck circumference, body mass index and the number of 4% desaturations/hour. WatchPat had an overall accuracy of 85.7% and a positive predictive value of 87.3% in diagnosing OSA (by predicted AHI above 5). In this large cohort of patients with high pretest probability of OSA, we built several models based on 4% oxygen desaturations, neck circumference, body mass index and several other variables. These simple models can be used at the point-of-care, in order to improve the diagnostic accuracy of the PAT-based testing, thus ameliorating the high rates of misclassification for OSA presence or disease severity.

Semi-fixed versus fixed oral appliance therapy for obstructive sleep apnea: A randomized crossover pilot study

Background/purpose

Although mandibular advancement oral appliances (OAs) are the most widely used and accepted therapeutic modality for obstructive sleep apnea (OSA), whether these maxillary and mandibular appliances should be semi-fixed or fixed remains uncertain. This randomized crossover pilot study compared the efficacy, side effects, and patient preference of semi-fixed and fixed OAs for the treatment of OSA.

Materials and methods

Patients with mild to moderate OSA were recruited and randomly assigned to either the semi-fixed or fixed OA group, whereby they used their assigned OA for the first 4 weeks, followed by assessments for sleep parameters (including the Apnea-Hypopnea Index [AHI]) and temporomandibular joint pain as a side effect. After a two-week washout period, patients were switched to the alternative OA for 4 weeks, followed by repeated assessments. Patient preference was assessed at the end of the completed treatment period.

Results

Fifteen patients were enrolled and completed the full study protocol. Both types of OAs were efficient in reducing the patient's AHI in comparison to baseline (i.e., without OA). However, there was no significant difference in AHI reduction between the semi-fixed and fixed OA devices. Regarding the side effect of temporomandibular joint pain and patient preference, the semi-fixed OA device was superior to the fixed OA device on both measures.

Conclusion

While both semi-fixed and fixed OAs are effective in treating patients with OSA, semi-fixed OAs are superior in regards to both patient preference and reduced side effects. Thus, semi-fixed OAs may be the preferred therapeutic modality for OSA.

Validation of peripheral arterial tonometry as tool for sleep assessment in chronic obstructive pulmonary disease

Obstructive sleep apnea (OSA) worsens outcomes in Chronic Obstructive Pulmonary Disease (COPD), and reduced sleep quality is common in these patients. Thus, objective sleep monitoring is needed, but polysomnography (PSG) is cumbersome and costly. The WatchPAT determines sleep by a pre-programmed algorithm and has demonstrated moderate agreement with PSG in detecting sleep stages in normal subjects and in OSA patients. Here, we validated WatchPAT against PSG in COPD patients, hypothesizing agreement in line with previous OSA studies. 16 COPD patients (7 men, mean age 61 years), underwent simultaneous overnight recordings with PSG and WatchPAT. Accuracy in wake and sleep staging, and concordance regarding total sleep time (TST), sleep efficiency (SE), and apnea hypopnea index (AHI) was calculated. Compared to the best fit PSG score, WatchPAT obtained 93% sensitivity (WatchPAT = sleep when PSG = sleep), 52% specificity (WatchPAT = wake when PSG = wake), 86% positive and 71% negative predictive value, Cohen’s Kappa (κ) = 0.496. Overall agreement between WatchPat and PSG in detecting all sleep stages was 63%, κ = 0.418. The mean(standard deviation) differences in TST, SE and AHI was 25(61) minutes (p = 0.119), 5(15) % (p = 0.166), and 1(5) (p = 0.536), respectively. We conclude that in COPD-patients, WatchPAT detects sleep stages in moderate to fair agreement with PSG, and AHI correlates well.

Detecting central sleep apnea in adult patients using WatchPAT-a multicenter validation study

Study objectives

To assess the accuracy of WatchPAT (WP—Itamar-Medical, Caesarea, Israel) enhanced with a novel systolic upstroke analysis coupled with respiratory movement analysis derived from a dedicated snoring and body position (SBP) sensor, to enable automated algorithmic differentiation between central sleep apnea (CSA) and obstructive sleep apnea (OSA) compared with simultaneous in-lab sleep studies with polysomnography (PSG).

Methods

Eighty-four patients with suspected sleep-disordered breathing (SDB) underwent simultaneous WP and PSG studies in 11 sleep centers. PSG scoring was blinded to the automatically analyzed WP data.

Results

Overall WP apnea-hypopnea index (AHI; mean ± SD) was 25.2 ± 21.3 (range 0.2–101) versus PSG AHI 24.4 ± 21.2 (range 0–110) (p = 0.514), and correlation was 0.87 (p < 0.001). Using a threshold of AHI ≥ 15, the sensitivity and specificity of WP versus PSG for diagnosing sleep apnea were 85% and 70% respectively and agreement was 79% (kappa = 0.867). WP central AHI (AHIc) was 4.2 ± 7.7 (range 0–38) versus PSG AHIc 5.9 ± 11.8 (range 0–63) (p = 0.034), while correlation was 0.90 (p < 0.001). Using a threshold of AHI ≥ 15, the sensitivity and specificity of WP versus PSG for diagnosing CSA were 67% and 100% respectively with agreement of 95% (kappa = 0.774), and receiver operator characteristic (ROC) area under the curve of 0.866, (p < 0.01). Using a threshold of AHI ≥ 10 showed comparable overall sleep apnea and CSA diagnostic accuracies.

Conclusions

These findings show that WP can accurately detect overall AHI and effectively differentiate between CSA and OSA.

Mobile App Use for Insomnia Self-Management: Pilot Findings on Sleep Outcomes in Veterans

Background

Sleep disturbance is a major health concern among US veterans who have served since 2001 in a combat theater in Iraq or Afghanistan. We report subjective and objective sleep results from a pilot trial assessing self-management–guided use of a mobile app (CBT-i Coach, which is based on cognitive behavioral therapy for insomnia) as an intervention for insomnia in military veterans.

Objective

The primary aim of this study was to evaluate changes in subjective and objective sleep outcomes from pre to postintervention.

Methods

Subjective outcomes included the Insomnia Severity Index, the Pittsburgh Sleep Quality Inventory, and sleep-related functional status. A wearable sleep monitor (WatchPAT) measured objective sleep outcomes, including sleep efficiency, percent rapid eye movement (REM) during sleep, sleep time, and sleep apnea. A total of 38 participants were enrolled in the study, with 18 participants being withdrawn per the protocol because of moderate or severe sleep apnea and 9 others who dropped out or withdrew. Thus, 11 participants completed the full 6-week CBT-i Coach self-management intervention (ie, completers).

Results

Completer results indicated significant changes in subjective sleep measures, including reduced reports of insomnia (Z=–2.68, P=.007) from pre (mean 16.63, SD 5.55) to postintervention (mean 12.82, SD 3.74), improved sleep quality (Z=–2.37, P=.02) from pre (mean 12.82, SD 4.60) to postintervention (mean 10.73, SD 3.32), and sleep-related functioning (Z=2.675, P=.007) from pre (mean 13.86, SD 3.69) to postintervention (mean 15.379, SD 2.94). Among the objective measures, unexpectedly, objective sleep time significantly decreased from pre to postintervention (χ²₂=7.8, P=.02). There were no significant changes in percent REM sleep or sleep efficiency.

Conclusions

These findings suggest that the CBT-i Coach app can improve subjective sleep and that incorporating objective sleep measures into future, larger clinical trials or clinical practice may yield important information, particularly by detecting previously undetected sleep apnea.

Trial Registration

ClinicalTrials.gov NCT02392000; http://clinicaltrials.gov/ct2/show/NCT02392000

Immediate impact of pharyngeal surgery on respiratory parameters in adults with obstructive sleep apnea

PURPOSE

One of the concerns regarding surgical treatment of the obstructive sleep apnea syndrome (OSAS) has been the possibility that these patients may experience a higher rate of perioperative complications, which could be aggravated by the upper airway edema caused by surgical trauma. The purpose of this study was to evaluate the immediate impact of pharyngeal surgery on the respiratory parameters of adult patients with OSAS.

METHODS

Twenty-three adults with moderate to severe OSAS and indications for pharyngeal surgery (with or without nasal surgery) were consecutively selected. The subjects underwent surgical treatment and monitoring of sleep parameters preoperatively (by type I polysomnography, PSG) and in the immediate postoperative period (arterial tonometry).

RESULTS

Twenty-two subjects, aged 20 to 59 years (mean ± SD, 38.0 ± 12.1 years), were included in the study. Nineteen (86.4%) were male. The mean apnea-hypopnea index (AHI) was 59.3 ± 26.0 events/h. Comparison between preoperative PSG and postoperative arterial tonometry revealed statistically significant reductions in AHI (p = 0.03), respiratory disturbance index (RDI) (p = 0.05), and oxygen desaturation index (p = 0.001), as well as increases in nadir oxyhemoglobin saturation (p = 0.003) and percentage of REM sleep (p = 0.01).

CONCLUSIONS

In this sample of patients with moderate and severe OSAS who underwent pharyngeal surgery, the vast majority of patients did not exhibit any deterioration of respiratory parameters in the immediate postoperative period. Conversely, there was a significant improvement in the parameters.

The effect of atrial fibrillation intervention on nocturnal respiratory events in elderly patients with persistent AF

BACKGROUND

Sleep-disordered breathing (SDB) and atrial fibrillation (AF) are associated. This study investigated the impact of AF intervention on 6-month home sleep testing data.

METHODS

Sixty-seven patients (aged 66 to 86, 53% male) with persistent AF were randomized (1:1:1) to direct current cardioversion (DCCV) (22 patients), permanent pacemaker (PPM) + atrioventricular node ablation (AVNA) + DCCV (22 patients) or AF ablation (23 patients). Baseline and 6-month multichannel home sleep tests with the Watch-PAT200 (Itamar Medical Lts., Caesarea, Israel) were recorded. Implantable cardiac monitors (ICMs) (Medtronic Reveal XT, Minneapolis, Minnesota) in the DCCV and AF ablation groups, and PPM Holters in the 'pace and ablate' group were utilized to assess cardiac rhythm beat-to-beat throughout the study period.

RESULTS

The prevalence of moderate-to-severe SDB [apnoea-hypopnoea index (AHI) ≥ 15/h] was 60%. At 6 months there was no change in AHI, Epworth sleepiness scale, sleep time, % REM sleep, respiratory desaturation index or central apnoeic events. Twenty-five patients (15 AF ablation, 9 DCCV and 1 following DCCV post-AVNA) maintained SR at 6 months confirmed on ICMs in these patients. AHI fell from 29.8 ± 26.6/h to 22.2 ± 20.4/h; P = 0.049.

CONCLUSIONS

SDB is highly prevalent in patients with persistent AF. Restoration of sinus rhythm, and the associated long-term recovery of haemodynamics, is associated with a significant reduction in AHI. This implicates reversal of fluid shift from the lower limbs to the neck region, a key mechanism in the pathogenesis of SDB.

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

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

A prospective, non-randomized evaluation of a novel low energy radiofrequency treatment for nasal obstruction and snoring

Background

Weak or inward-bent cartilage of the nasal sidewall at the level of the internal nasal valve (INV) can produce narrowness or collapse of the nasal valve. This is a common cause of impaired nasal breathing during daily activities and there is also an established connection between nasal obstruction and snoring. The condition is often difficult to treat, although even a small enlargement of the lumen at the nasal valve can lead to a significant improvement in the ease of nasal breathing.

Methods

The primary objective of this prospective study was to evaluate the safety and efficacy of the Vivaer system for the treatment of narrowed nasal valves and to measure changes in the symptoms of nasal obstruction and snoring. The Vivaer system uses low energy radiofrequency to remodel the nasal sidewall in order to improve airflow.

Results

The study involved 31 patients presenting from 1st September 2017 to 1st May 2018 with symptoms of nasal obstruction and snoring. In all patients, an improvement was observed in nasal breathing measured by NOSE score, sleep quality by SOS questionnaire and quality of life as measured by EQ-5D and SNOT-22.

Conclusion

Vivaer intranasal remodeling can provide a durable and well-tolerated non-invasive treatment for those patients who are suffering congestion due to narrowness or collapse of the INV.

Validating the Watch-PAT for Diagnosing Obstructive Sleep Apnea in Adolescents

STUDY OBJECTIVES

The aim of this study was to evaluate the accuracy of the Watch-PAT 200 (WP200) for diagnosing obstructive sleep apnea (OSA) in adolescents compared with polysomnography (PSG) according to the respiratory rules for children (RRC) and adults (RRA).

METHODS

A total of 38 adolescents (mean age 15.1 ± 1.4 years; male 28 [73.7%]; body mass index [BMI] 23.1 ± 5.5 kg/m²) with suspected OSA were assessed with the WP200 and standard PSG simultaneously between July 2014 and September 2015 at a tertiary university hospital. All WP200 data were assessed according to the automatic algorithm, and PSG data were scored according to the RRC and RRA. We examined the correlation, agreement, and concordance in the apnea-hypopnea index (AHI) and minimum arterial oxygen saturation (mSaO₂) between the WP200 and PSG-RRC or PSG-RRA.

RESULTS

There were high correlations (r = .945, P < .001 [AHI-WP200 versus AHI-PSG-RRC]; r = .945, P < .001 [AHI-WP200 versus AHI-PSG-RRA]; r = .921, P < .001 [mSaO₂-WP versus mSaO₂-PSG]) and good agreements in AHI and mSaO₂ between the WP200 and PSG. In addition, there were high concordances in AHI severity (Kendall tau-b = .848, P < .001 [AHI-WP200 versus AHI-PSG-RRC]; Kendall tau-b = .944, P < .001 [AHI-WP200 versus AHI-PSG-RRA]) between the WP200 and PSG.

CONCLUSIONS

The WP200 may be a clinically reliable tool for diagnosing OSA in adolescents.

Addition of frontal EEG to adult home sleep apnea testing: does a more accurate determination of sleep time make a difference?

RATIONALE

Home sleep apnea testing (HSAT) typically does not include electroencephalogram (EEG) monitoring for sleep assessment. In patients with insomnia and low sleep efficiency, overestimation of the sleep period can result from absence of EEG, which will reduce sleep disordered breathing (SDB) indices and may lead to a false-negative result.

OBJECTIVE

To validate a single channel frontal EEG for scoring sleep versus wake against full EEG during polysomnography, and then to examine the utility of adding this single channel EEG to standard HSAT to prevent false-negative results.

METHODS

Epoch-by-epoch validation for sleep scoring of single channel EEG versus full PSG was first performed in 21 subjects. This was followed by a separate retrospective analysis of 207 consecutive HSATs in adults performed in a university-affiliated sleep center using the Somte (Compumedics) HSAT with one frontal EEG as well as chin EMG, nasal airflow, oxyhemoglobin saturation, respiratory effort, pulse rate, and body position. Each study was scored twice, with (HSAT_EEG) and without the EEG signal visible (HSAT_Polygraphy), to calculate AHI4 and RDI and the effect on OSA diagnosis and severity. Analyses were repeated in 69 patients with poor sleep suggesting insomnia plus Epworth Sleepiness Scale < 7 as well as in 38 patients ultimately shown to have sleep efficiency < 70% on HSAT with EEG.

MEASUREMENTS AND MAIN RESULTS

Single channel and full EEG during polysomnography agreed on sleep versus wake in 92-95% of all epochs. HSAT without EEG overestimated the sleep period by 20% (VST = 440 ± 76 min vs TST = 356 ± 82 min), had a false-negative rate of 8% by AHI4 criteria, and underestimated disease severity in 11% of all patients. Sub-group analysis of patients with subjective poor sleep suggesting insomnia did not change the results. Patients later shown to have low sleep efficiency had lower SDB indices and a 20.8% false negative rate of sleep apnea diagnosis.

CONCLUSIONS

Although overall false negative rates using HSAT_Polygraphy were moderate, suggesting utility for ruling out OSA, there was a specific subgroup in whom there were significant missed diagnoses. However, we were unable to identify this subgroup a priori.

Comparison of upper airway patency in patients with mild obstructive sleep apnea during dexmedetomidine or propofol sedation: a prospective, randomized, controlled trial

Background

In addition to propofol, dexmedetomidine is a suitable alternative for intraoperative sedation in procedures requiring regional anesthesia. To date, however, little is known about the influences of each drug on upper airway patency. Accordingly, the authors investigated differences between dexmedetomidine and propofol sedation in the occurrence of upper airway obstruction and requirements for airway intervention in patients with mild obstructive sleep apnea.

Methods

Patients with an apnea/hypopnea index of 5–14/h according to Watch-PAT 200 analysis were enrolled in this study. Spinal anesthesia was routinely performed for surgery. Intraoperative sedation was initiated using either dexmedetomidine or propofol infusion at a level of modified observer’s assessment of alertness/sedation scale 3. The primary outcome was the proportion of patients exhibiting signs of upper airway obstruction. A sign of upper airway obstruction was defined as no detection of end-tidal carbon dioxide for at least 10 s despite respiratory efforts.

Results

A total of 50 patients were included in the final analysis (dexmedetomidine [n = 26]; propofol [n = 24]). During the intraoperative sedation period, there was a significantly lower proportion of patients exhibiting signs of upper airway obstruction in the dexmedetomidine group than in the propofol group (11.5% vs. 41.7%, P = 0.035). An artificial airway was inserted in 1 patients (3.8%) and 5 patient (20.8%) in the dexmedetomidine and propofol groups, respectively (P = 0.093).

Conclusion

Dexmedetomidine sedation was associated with a lower incidence of upper airway obstruction than propofol sedation in patients with mild obstructive sleep apnea.

Trial registration number

Clinical trials.gov (NCT02993718): Retrospectively registered.

Devices for home detection of obstructive sleep apnea: A review

One of the most common sleep-related disorders is obstructive sleep apnea, characterized by a reduction of airflow while breathing during sleep and cause significant health problems. This disorder is mainly diagnosed in sleep labs with polysomnography, involving high costs and stress for the patient. To address this situation multiple systems have been proposed to conduct the examination and analysis in the patient's home, using sensors to detect physiological signals that are examined by algorithms. The objective of this research is to review publications that show the performance of different devices for ambulatory diagnosis of sleep apnea. Commercial systems that were examined by an independent research group and validated research projects were selected. In total 117 articles were analysed, including a total of 50 commercial devices. Each article was evaluated according to diagnostic elements, level of automatisation implemented and the deducted level of evidence and quality rating. Each device was categorized using the SCOPER categorization system, including an additional proposed category, and a final comparison was performed to determine the sensors that provided the best results.

Obstructive sleep apnea and postoperative complications among patients undergoing gynecologic oncology surgery

OBJECTIVE

To investigate the prevalence of obstructive sleep apnea (OSA), physiological or risk factors associated with OSA, and OSA-associated postoperative complications among patients undergoing gynecologic oncology surgery.

METHODS

A prospective observational study enrolled gynecologic oncology patients undergoing abdominal surgery at a center in the UK between August 2009 and January 2013. All patients underwent perioperative sleep oximetry for the diagnosis of OSA. Data assessed included the body mass index, the STOP-Bang score, the Epworth Sleepiness Scale score, the apnea-hypopnea index, and postoperative complications. Associations were determined between preoperative OSA and postoperative OSA, postoperative complications, and risk factors such as body mass index, age, STOP-Bang score, and Epworth score.

RESULTS

Among 160 participants, 72 (45.0%) were obese and 80 (50.0%) had OSA. Obesity, older age (more than 65 years), and a neck circumference of 40 cm or more were significantly associated with OSA. Overall, 58 (36.3%) patients had postoperative complications; 21 (13.1%) had surgical complications and 37 (23.1%) had medical complications. Complications were not associated with OSA (P=0.612). Four (2.5%) patients died; mortality was not associated with OSA (P=0.810).

CONCLUSION

OSA is common among gynecologic oncology patients. Portable sleep oximetry identifies gynecology patients who have OSA or require postoperative critical care. Obesity is associated with OSA, but OSA is not associated with postoperative complications in gynecologic oncology patients.

Ultrasonographic Detection of Airway Obstruction in a Model of Obstructive Sleep Apnea

Purpose Obstructive sleep apnea (OSA) is a common clinical disorder characterized by repetitive airway obstruction during sleep. The gold standard for diagnosis of OSA, polysomnogram (PSG), cannot anatomically localize obstruction. Precise identification of obstruction has potential to improve outcomes following surgery. Current diagnostic modalities that provide this information require anesthesia, involve ionizing radiation or disrupt sleep. To mitigate these problems, we conceived that ultrasound (US) technology may be adapted (i) to detect, quantify and localize airway obstruction and (ii) for translational application to home-based testing for OSA. Materials and Methods Segmental airway collapse was induced in 4 fresh cadavers by application of negative pressure. Following visualization of airway obstruction, a rotary US probe was used to acquire transcervical images of the airway before and after induction of obstruction. These images (n=800) were analyzed offline using image processing algorithms. Results Our results show that the non-obstructed airway consistently demonstrated the presence of a US air-tissue interface. Importantly, automated detection of the air-tissue interface strongly correlated with manual measurements. The algorithm correctly detected an air-tissue interface in 90% of the US images while incorrectly detecting it in 20% (area under the curve=0.91). Conclusion The non-invasive detection of airway obstruction using US represents a major step in expanding OSA diagnostics beyond PSG. The preliminary data obtained from our model could spur further research in non-invasive localization of obstruction. US offers the benefit of precise localization of the site of obstruction, with potential for improving outcomes in surgical management.

Effective Apnea-Hypopnea Index ("Effective AHI"): A New Measure of Effectiveness for Positive Airway Pressure Therapy

STUDY OBJECTIVES

To assess a new measure of positive airway pressure (PAP) effectiveness, the Effective AHI, which accounts for sleep disordered breathing events during the time PAP is (PAP On) and is not (PAP Off) being used. A secondary aim was to test the accuracy of the Watch-PAT 200 (WP) portable monitor for measurement of the Effective AHI.

METHODS

A prospective two-center cohort study design was used to evaluate patients who had been prescribed PAP therapy for ≥ 2 months. The primary outcome measure was the Effective AHI as determined by an in-laboratory polysomnogram (PSG) where patients used their PAP machine as they did at home, and concomitantly wore the WP. The Effective AHI equals the sum of apneas and hypopneas with PAP On and PAP Off divided by hours of total sleep time.

RESULTS

Twenty-eight adult patients (75% men, age 51.4 ± 10.8 years [mean ± SD]) comprised the study sample. The mean Effective AHI of 18.3, was significantly lower than the mean Diagnostic AHI of 67.9 (P < 0.0001). All patients using PAP ≥ 6 h had an Effective AHI < 5. For patients using PAP < 6 h, Effective AHI scores < 5 only occurred in patients who slept in a non-supine position during PAP Off time; leaving 63.6% of patients with residual moderate-to-severe OSA. There was a high correlation between the PSG and WP for the Effective AHI (r = 0.871).

CONCLUSIONS

Significant disease burden, as objectively measured by the Effective AHI, may still exist in many patients with severe OSA in whom PAP therapy is not utilized for the entire sleep period. The WP is a reasonably accurate device to measure the Effective AHI.

Obstructive Sleep Apnea in Patients with Branch Retinal Vein Occlusion: A Preliminary Study

PURPOSE

Our study aimed to determine whether obstructive sleep apnea (OSA) is common among branch retinal vein occlusion (BRVO) patients without systemic risk factors using a Watch PAT-100 portable monitoring device.

METHODS

The study participants included consecutive patients with BRVO of less than 3 months duration without any risk factors known to be associated with OSA (diabetes, coronary artery disease, stroke, hematologic diseases, autoimmune disease, etc.) except for hypertension. All patients underwent full-night unattended polysomnography by means of a portable monitor Watch PAT-100 device. The apnea-hypopnea index (AHI) was calculated as the average number of apnea and hypopnea events per hour of sleep, and an AHI score of five or more events was diagnosed as OSA.

RESULTS

Among 19 patients (6 males and 13 females), 42.1% (8 of 19) had an AHI reflective of OSA. In the 13 patients who had no concurrent illness, including hypertension, 30.8% (4 of 13) had positive test results for OSA; three of these patients were ranked as mild OSA, while one had moderate OSA. The OSA group had an average AHI of 12.3 ± 7.8, and the average AHI was 2.0 ± 0.9 in the non-OSA group. Although it was not statistically proven, we found that OSA patients experienced a more severe form of BRVO.

CONCLUSIONS

We found a higher than expected rate of OSA in BRVO patients lacking concomitant diseases typically associated with OSA. Our findings suggest that OSA could be an additional risk factor in the pathogenesis of BRVO or at least a frequently associated condition that could function as a triggering factor.

Relationship Between Snoring Intensity and Severity of Obstructive Sleep Apnea

Objectives

The aim of this study was to determine the relationship between the intensity of snoring and severity of sleep apnea using Watch-PAT (peripheral arterial tone) 100.

Methods

A total of 404 patients (338 males and 66 females) who underwent home-based portable sleep study using Watch-PAT 100 for obstructive sleep apnea (OSA) from January 2009 through December 2011 were included in this study. Subjects were divided into 4 groups; no OSA (PAT apnea hypopnea index [pAHI]<5/hour), mild OSA (5≤pAHI<15/hour), moderate OSA (15≤pAHI<30/hour), or severe OSA groups (pAHI≥30/hour). Mean snoring intensity and percent sleep time with snoring intensity greater than 40, 50, and 60 dB were measured by Watch-PAT 100. Correlations of these parameters with apnea hypopnea index (AHI), respiratory disturbance index (RDI), and oxygen desaturation index were assessed.

Results

The mean age and body mass index were 46.5±14.8 years and 24.7±3.4 kg/m², respectively. Mean AHI and RDI were 16.5±15.3/hour and 20.8±14.3/hour, respectively. The mean snoring intensity in the no, mild, moderate, and severe OSA groups was 44.0±2.7, 45.4±6.0, 47.7±5.0, and 50.5±5.6 dB, respectively (P<0.001). There was a positive correlation between snoring intensity and pAHI or PAT RDI (pRDI) (r=0.391 and r=0.385, respectively, both P<0.001). There was also a positive correlation between percent sleep time with the snoring intensity greater than 50 dB and pAHI or pRDI (r=0.423 and r=0.411, respectively, both P<0.001).

Conclusion

This study revealed that the intensity of snoring increased with the severity of sleep apnea, which suggests that the loudness of snoring might be an indicator of the severity of OSA.

Accuracy of peripheral arterial tonometry in the diagnosis of obstructive sleep apnea

Introduction

The use of handheld devices that assess peripheral arterial tonometry has emerged as an auxiliary method for assessment and diagnosis of obstructive sleep apnea syndrome.

Objective

To evaluate the accuracy of peripheral arterial tonometry in the diagnosis of obstructive sleep apnea.

Methods

Contemporary cohort cross-sectional study. Thirty patients with suspected obstructive sleep apnea underwent peripheral arterial tonometry and assisted nocturnal polysomnography concomitantly.

Results

The mean apnea/hypopnea index by peripheral arterial tonometry was significantly higher than that by polysomnography (p < 0.001), but the values of both sleep studies were significantly correlated (r = 0.762). There was a high correlation between variables: minimum oxygen saturation (r = 0.842, p < 0.001), oxygen saturation < 90% (r = 0.799, p < 0.001), and mean heart rate (r = 0.951, p < 0.001). Sensitivity and specificity were 60% and 96.2% (AUC: 0.727; p = 0.113), respectively, when at a threshold value of 5 events/h. In severe cases (≥30 events/h), the result was a sensitivity of 77.8% and a specificity of 86.4% (AUC: 0.846, p = 0.003).

Conclusion

Peripheral arterial tonometry is a useful portable device for the diagnosis of obstructive sleep apnea; its accuracy is higher in moderate and severe cases.

Using the Karolinska Sleep Questionnaire to identify obstructive sleep apnea syndrome in a sleep clinic population

INTRODUCTION

In Scandinavia, portable monitoring has virtually replaced standard polysomnography for diagnosis of obstructive sleep apnea syndrome (OSAS). Because waiting times for specialized OSAS care remain long, an accurate screening tool to exclude low-risk patients from diagnostic testing would be valuable.

OBJECTIVES

To examine the diagnostic accuracy of the Karolinska Sleep Questionnaire (KSQ) for OSAS.

METHODS

Consecutive patients, 30–66 years old, attending a large sleep clinic in Sweden for OSAS evaluation completed the KSQ and underwent in-home portable monitoring and medical history evaluation. OSAS was defined as apnea-hypopnea index ≥5 with symptoms of disease. We calculated sensitivity and specificity of apnea/snoring and sleepiness indices of the KSQ. Retrospectively, we combined six KSQ items (snoring, breathing cessations, disturbed sleep, etc.) and four clinical variables (age, sex, body mass index, smoking status) predictive of OSAS into a new instrument, which we also evaluated. Instrument score ranged between 0 and 21; a higher score indicated more severe symptoms.

RESULTS

Of 103 patients, 62 were diagnosed with OSAS. Sensitivity and specificity of the indices were 0.56 and 0.68 (apnea/snoring), and 0.37 and 0.71 (sleepiness). The new instrument performed optimally at a score of 9. Sensitivity was 0.76 (95% confidence interval 0.63–0.86) and specificity 0.88 (0.74–0.96). Between 19.4% and 50.5% of patients were unaware of having apnea/snoring symptoms.

CONCLUSIONS

Diagnostic accuracy of the apnea/snoring and sleepiness indices for OSAS was poor but could be improved by combining clinical and KSQ items. The usefulness of the apnea/snoring index and the combined instrument was questionable because of extensive symptom unawareness.

Relationships between polypharmacy and the sleep cycle among active-duty service members

CONTEXT

Sleep disorders are frequent clinical presentations, especially among active-duty service members. Medications are one factor that can affect sleep in many ways.

OBJECTIVE

To determine the effect of increasing numbers of medications on the sleep cycle of active-duty service members.

METHODS

Medical records for active-duty service members who completed enhanced sleep assessments at the Psychiatry Continuity Service at Walter Reed National Military Medical Center from October 1, 2010, through November 30, 2013, were retrospectively reviewed. Data were collected on home sleep study findings, sleep-related self-report instrument scores, and active medications.

RESULTS

A total of 135 medical records were reviewed. One hundred patients (74.07%) had an active prescription for a psychoactive drug. Among all patients, the mean (SD) number of active medications per participant was 2.52 (2.09), with 118 patients (82.96%) having an active medication for depression or insomnia. As the number of prescribed medications increased, the percentage of the sleep cycle in deep sleep decreased (P=.049), the percentage of light sleep increased (P=.016), the percentage of rapid eye movement sleep decreased (P=.083), and the first episode of deep sleep was delayed (P=.056). An increased number of medications had no significant impact on total sleep time (P&gt;.05).

CONCLUSION

An increasing number of medications did not influence total sleep time but negatively affected the sleep cycle.

The efficacy of Watch PAT in obstructive sleep apnea syndrome diagnosis

Polysomnography is currently considered as the gold standard for the diagnosis of obstructive sleep apnea syndrome (OSAS). But high expense and the backlog of the sleep centers have resulted in a search for an alternative method of diagnosis. The aim of this study is to assess the efficacy and reliability of Watch PAT as an alternate option in OSAS diagnosis. The patients have worn a Watch PAT(®) 200 device in the sleep laboratory during a standard polysomnography. The correlation in REM and Non-REM AHI scores, sleep periods and the mean O2 saturation percentage between Watch PAT and PSG sleep studies were assessed. There was a statistically significant very strong correlation between PSG and Watch PAT AHI scores (Spearman's rho = 0.802 p < 0.001). The mean recording time with PSG and Watch PAT was 463.06 ± 37.08 and 469.33 ± 72.81 min, respectively, and there was no statistically significant difference (p = 0.068). However, there was a statistically significant difference between two methods regarding the average sleep time and REM sleep period. No statistically significant difference was revealed in the mean O2 saturation percentage (p < 0.001). Watch PAT is an efficient device and is considered to be an adjunctive diagnostic method for PSG in diagnosis of OSAS.

The Effect of the Transition to Home Monitoring for the Diagnosis of OSAS on Test Availability, Waiting Time, Patients' Satisfaction, and Outcome in a Large Health Provider System

During 2009, the Haifa district of Clalit Health Services (CHS) has switched from in-lab polysomnography (PSG) to home studies for the diagnosis of obstructive sleep apnea (OSA). We assessed the effects of this change on accessibility, waiting time, satisfaction, costs, and CPAP purchase by the patients. Data regarding sleep studies, CPAP purchase, and waiting times were collected retrospectively from the computerized database of CHS. Patients' satisfaction was assessed utilizing a telephone questionnaire introduced to a randomized small sample of 70 patients. Comparisons were made between 2007 and 2008 (in-lab PSGs) and 2010 and 2011 (when most studies were ambulatory). Of about 650000 insured individuals in the Haifa district of CHS, 1471 sleep studies were performed during 2007-2008 compared to 2794 tests during 2010-2011. The average waiting time was 9.9 weeks in 2007-2008 compared to 1.1 weeks in 2010-2011 (P < 0.05). 597 CPAPs were purchased in 2007-2008 compared to 831 in 2010-2011. The overall patients' satisfaction was similar, but discomfort tended to be higher in the in-laboratory group (4.1 vs 2.7 in a scale of 0-10; P = 0.11). Switching to ambulatory diagnosis improved the test accessibility and reduced the waiting times. Patients' satisfaction remained similarly high. The total direct cost of OSA management was reduced.

Clinical usefulness of watch-PAT for assessing the surgical results of obstructive sleep apnea syndrome

OBJECTIVE

This study aimed to assess the accuracy and clinical efficacy of a wrist-worn device that is based on peripheral arterial tonometry (watch-PAT) to evaluate the surgical results of obstructive sleep apnea (OSA) syndrome subjects.

STUDY DESIGN AND METHOD

Thirty-five subjects who were diagnosed with OSA and underwent sleep surgeries such as septoplasty, tonsillectomy, or uvuloplasty to correct their airway collapse, participated in this study; the watch-PAT-derived respiratory disturbance index (RDI), apnea and hypopnea index (AHI), lowest oxygen saturation, and valid sleep time were measured after the sleep surgery.

RESULTS

The present study showed that RDI (32.8 ± 10.7 vs. 14.8 ± 7.5), AHI (30.3 ± 8.6 vs. 13.4 ± 8.2 events/h), lowest oxygen saturation (78.2% ± 8.4% vs. 90.5% ± 7.1%), and valid sleep time (329.1 ± 47.2 min and a postoperative value of 389.1 ± 50.1 min) recovered to within a normal range after surgery in 28 subjects. In addition, good agreement was found between watch-PAT-derived factors and visual analogue scales for changes in subjective symptoms, such as snoring, apnea, and daytime somnolence. Seven of the 35 subjects showed no improvement for their subjective symptoms and complained of snoring and apnea after surgery. We found that the RDI and AHI of those 7 subjects were not reduced, and the changes between pre- and postoperative values which were measured with watch-PAT were minimal. Their postoperative lowest oxygen saturation and valid sleep time were not elevated per the watch-PAT. The results support a strong correlation between the findings from watch-PAT and improved symptoms after surgical correction of an airway collapse.

CONCLUSIONS

Our study provides evidence that the factors measured by the watch-PAT might be reliable indicators of symptomatic changes in OSA subjects after sleep surgery and also shows that the watch-PAT is a highly sensitive portable device for estimating treatment results in OSA.

Assessment of a portable monitoring device WatchPAT 200 in the diagnosis of obstructive sleep apnea

We assessed the accuracy of a wrist-worn device WatchPAT 200 for the diagnosis of obstructive sleep apnea (OSA) and sleep and wakefulness indicators compared to standard polysomnography (PSG) using American Academy of Sleep Medicine (AASM) criteria. Twenty-eight adults with suspected OSA underwent a standard in-hospital PSG while wearing a WatchPAT 200. PSG events were manually scored using AASM criteria; WatchPAT 200 data were collected and analyzed by an automatic algorithm. The accuracy of WatchPAT 200 algorithm in apnea hypopnea index (AHI) and sleep-wake detection was compared to standard PSG methodology. The study population consisted of 21 males and 7 females, mean age of 47.45 ± 13.46 years, and mean body mass index of 29.99 ± 5.74 kg/m(2). For AHI, the mean PSG score for events per hour was 23.00 ± 21.55 compared to a mean score of 25.99 ± 19.09 for WatchPAT (r = 0.92, P < 0.001). The agreement of the sleep-wake assessment based on 30-s bins between the PSG and the WatchPAT was 89 ± 6 %. WatchPAT 200 detected OSA based on AHI with comparable accuracy, and provided a reasonably accurate estimation of sleep and wakefulness in patients with OSA on an epoch-by-epoch basis.

Reliability of the Watch-PAT 200 in detecting sleep apnea in highway bus drivers

OBJECTIVE

To predict the validity of Watch-PAT (WP) device for sleep disordered breathing (SDB) among highway bus drivers.

METHOD

A total number of 90 highway bus drivers have undergone polysomnography (PSG) and Watch-PAT test simultaneously. Routine blood tests and the routine ear-nose-throat (ENT) exams have been done as well.

RESULTS

The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were 89.1%, 76.9%, 82% and 85.7% for RDI > 15, respectively. WRDI, WODI, W < 90% duration and Wmean SaO2 results were well correlated with the PSG results. In the sensitivity and specificity analysis, when diagnosis of sleep apnea was defined for different cut-off values of RDI of 5, 10 and 15, AUC (95%CI) were found as 0.84 (0.74-0.93), 0.87 (95%CI: 0.79-0.94) and 0.91 (95%CI: 0.85-0.97), respectively. There were no statistically significant differences between Stage1+2/Wlight and Stage REM/WREM. The percentage of Stage 3 sleep had difference significant statistically from the percentage of Wdeep. Total sleep times in PSG and WP showed no statistically important difference. Total NREM duration and total WNREM duration had no difference either.

CONCLUSION

Watch-PAT device is helpful in detecting SDB with RDI > 15 in highway bus drivers, especially in drivers older than 45 years, but has limited value in drivers younger than 45 years old who have less risk for OSA. Therefore, WP can be used in the former group when PSG is not easily available.