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

Comparative study of the SleepImage ring device and polysomnography for diagnosing obstructive sleep apnea

Purpose We aim to evaluate the diagnostic performance of the SleepImage Ring device in identifying obstructive sleep apnea (OSA) across different severity in comparison to standard polysomnography (PSG). Methods Thirty-nine patients (mean age, 56.8 ± 15.0 years; 29 [74.3%] males) were measured with the SleepImage Ring and PSG study simultaneously in order to evaluate the diagnostic performance of the SleepImage device for diagnosing OSA. Variables such as sensitivity, specificity, positive and negative likelihood ratio, positive and negative predictive value, and accuracy were calculated with PSG-AHI thresholds of 5, 15, and 30 events/h. Receiver operating characteristic curves were also built according to the above PSG-AHI thresholds. In addition, we analyzed the correlation and agreement between the apnea-hypopnea index (AHI) obtained from the two measurement devices. Results There was a strong correlation (r = 0.89, P < 0.001 and high agreement in AHI between the SleepImage Ring and standard PSG. Also, the SleepImage Ring showed reliable diagnostic capability, with areas under the receiver operating characteristic curve of 1.00 (95% CI, 0.91, 1.00), 0.90 (95% CI, 0.77, 0.97), and 0.98 (95% CI, 0.88, 1.000) for corresponding PSG-AHI of 5, 15 and 30 events/h, respectively. Conclusion The SleepImage Ring could be a clinically reliable and cheaper alternative to the gold standard PSG when aiming to diagnose OSA in adults.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13534-023-00304-9.

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.

Remote Patient Monitoring for Neuropsychiatric Disorders: A Scoping Review of Current Trends and Future Perspectives from Recent Publications and Upcoming Clinical Trials

Introduction:

Telemedicine and remote patient monitoring are rapidly growing fields. This scoping review provides an update on remote patient monitoring for neuropsychiatric disorders from recent publications and upcoming clinical trials.

Methods:

Publications (PubMed and ICHUSHI; published January 2010 to February 2021) and trials (ClinicalTrials.gov and Japanese registries; active or recruiting by March 2021) that assessed wearable devices for remote management and/or monitoring of patients with neuropsychiatric disorders were searched. The review focuses on disorders with ≥3 publications.

Results:

We identified 44 publications and 51 active or recruiting trials, mostly from 2019 or 2020. Research on digital devices was most common for Parkinson's disease (11 publications and 19 trials), primarily for monitoring motor symptoms and/or preventing falls. Other disorders (3–5 publications each) included epilepsy (electroencephalogram [EEG] and seizure prediction), sleep disorder (sleep outcomes and behavioral therapies), multiple sclerosis (physical activity and symptoms), depression (physical activity, symptoms, and behavioral therapies), and amyotrophic lateral sclerosis (symptoms). Very few studies focused on newly emerging technologies (e.g., in-ear EEG and portable oximeters), and few studies integrated remote symptom monitoring with telemedicine.

Discussion:

Currently, development of digital devices for daily symptom monitoring is focused on Parkinson's disease. For the diseases reviewed, studies mostly focused on physical activity rather than psychiatric or nonmotor symptoms. Although the validity and usefulness of many devices are established, models for implementing remote patient monitoring in telehealth settings have not been established.

Conclusions:

Verification of the clinical effectiveness of digital devices combined with telemedicine is needed to further advance remote patient care for neuropsychiatric disorders.

A comparison of automated and manual sleep staging and respiratory event recognition in a portable sleep diagnostic device with in-lab sleep study

STUDY OBJECTIVES

The objectives were to develop and validate an algorithm for editing WatchPAT scoring and assess the accuracy in an unselected clinical population as well as age and sex substrata.

METHODS

Two hundred sixty-two participants were enrolled to undergo WatchPAT simultaneously with in-lab polysomnography (PSG) recordings for developing (n = 30), optimizing (n = 62), and validating (n = 170) an algorithm to review and edit respiratory events and sleep architecture of WatchPAT recordings, which was based on visual inspection of WatchPAT signals. Apnea-hypopnea index (AHI) and sleep indices were compared with PSG-derived and automated WatchPAT indices.

RESULTS

Although estimation of total sleep time (TST) was comparable between automated and manual algorithm, estimation of rapid eye movement (REM) sleep time was markedly improved with manual editing from 0.48, 23.0 min (-43.9 to 89.8) to 0.64, 18.3 min (-32.6 to 69.1) (correlation with PSG, mean difference [reference range] from PSG, respectively). Manual scoring also improved correlation and agreement with PSG AHI from 0.65, 2.5 events/h (-24.0 to 28.9) to 0.81, -4.5 events/h (-22.5 to 13.6) as well as concordance for categorical agreement of sleep-disordered breathing severity and concordance for detecting severe REM-related sleep-disordered breathing. Interscorer reliabilities were excellent for TST and AHI, while good for REM sleep time. The automated algorithm performed better in younger than in older patients, while performed similarly between men and women with respect to concordance statistics. The manual algorithm markedly improved concordances more in older patients and women than in their counterparts.

CONCLUSIONS

Our manual editing algorithm improves correlation and agreement with PSG-derived sleep and breathing indices. Sex and age influence the accuracy of automated analysis and the performance of manual editing on AHI concordance.

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.

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.

Watch Peripheral Arterial Tonometry in the Diagnosis of Pediatric Obstructive Sleep Apnea

Objective To assess the accuracy and clinical reliability of watch peripheral arterial tonometry (PAT) compared with polysomnography (PSG) for the diagnosis of pediatric obstructive sleep apnea (OSA). Study Design Prospective, diagnostic test study. Setting National tertiary referral hospital. Subjects and Methods Patients aged 8 to 15 years with clinically suspected OSA were recruited. All participants underwent PSG and PAT simultaneously in the sleep laboratory. Results Thirty-six patients were included, with a mean age of 10.2 ± 1.8 years. Median (interquartile range) of the apnea hypopnea index (AHI) was 8.0 (5.5-12) and 2.9 (0.5-7.5) events/h, median oxygen desaturation index (ODI) was 2.5 (1.4-8.3) and 1.3 (0.2-3.8) events/h, mean ± standard deviation total sleep time was 398.4 ± 38.3 and 401.9 ± 36.1 minutes, and mean minimum oxygen saturation was 87.1% ± 8.1% and 89.4% ± 7.1% for PSG and PAT sleep parameter results, respectively. Agreement between methods was excellent for the AHI (intraclass correlation coefficient [ICC]: 0.89; 95% CI, 0.40-0.96; P < .001) and ODI (ICC: 0.87; 95% CI, 0.69-0.94; P < .001). Correlation between methods was very good for the ODI ( r = 0.83; 95% CI, 0.67-0.90; P < .001) and moderate for the AHI ( r = 0.64; 95% CI, 0.30-0.85; P < .001). From the receiver operating characteristic curve constructed to assess PAT diagnostic capability, AHI of PAT (W-AHI) at a cutoff of 3.5 events/h provided the highest accuracy (76.9% sensitivity, 78.3% specificity), while W-AHI at 10 events/h yielded 91.3% specificity for diagnosing severe OSA. Conclusion PAT correlated well and had good agreement with PSG. Children with W-AHI ≥10 had high specificity for the diagnosis of severe OSA. Larger studies with PAT designed for children across all age ranges and with a normal control group are still needed.

Impact of Arterial Stiffness on WatchPAT Variables in Patients With Obstructive Sleep Apnea

STUDY OBJECTIVES

The WatchPAT is a wrist-worn portable device that creates integration data regarding peripheral arterial tone (PAT), oxyhemoglobin saturation, heart rate, and actigraphy to diagnose or screen for obstructive sleep apnea (OSA). Previous studies have demonstrated the efficacy and validity of respiratory variables measured by the WatchPAT compared to those using polysomnography (PSG). However, the effects of arterial stiffness or atherosclerosis on WatchPAT parameters remain to be elucidated.

METHODS

Sixty-one consecutive patients with suspected OSA who underwent home-based testing with the WatchPAT 200, standard in-laboratory overnight polysomnography (PSG), and pulse wave velocity (PWV) as an index of arterial stiffness were studied. All PSG recordings were scored manually using the American Academy of Sleep Medicine criteria, whereas WatchPAT data were analyzed by an automatic algorithm. We evaluated how arterial stiffness affected respiratory event index data in WatchPAT (WP-AHI), because WP-AHI could be partly influenced by PAT, comparing WP-AHI and the apneahypopnea index measured by PSG (PSG-AHI) in consideration of PWV result.

RESULTS

Overall, WP-AHI was moderately correlated to PSG-AHI, but WP-AHI was significantly lower than PSG-AHI (28.4 ± 19.2 versus 53.6 ± 30.2 events/h, P < .0001). For the lower PWV group, there was a significant correlation and good agreement between the WP-AHI and PSG-AHI, but as the PWV increased, there was low correlation between the WP-AHI and PSG-AHI.

CONCLUSIONS

Arterial stiffness may affect the respiratory variables measured by WatchPAT in patients with OSA.

COMMENTARY

A commentary on this article appears in this issue on page 301.

The sympathetic nervous system and catecholamines metabolism in obstructive sleep apnoea

Obstructive sleep apnoea (OSA) is the most common sleep disorder of breathing in middle-aged and overweight subjects. It features recurrent episodes of upper airway total (apnoea) o partial (hypopnea) collapse during sleep, which are associated with a reduction in blood oxygen saturation and with arousal from sleep to re-establish airway patency. An association of OSA with dysregulation of the autonomous nervous system (ANS) and altered catecholamines (CAs) metabolism has been contended for years. However, the pathophysiology mechanisms underlying these alterations remain to be fully clarified. Nonetheless, these alterations are deemed to play a key pathogenic role in the established association of OSA with several conditions besides arterial hypertension (HT), including coronary artery disease, stroke, and, more in general, with increased risk of cardiovascular (CV) events. Hence, in this review we will analyse the relationship between the sleep disturbances associated with OSA and the altered function of the ANS, including CAs metabolism.