The sleep position trainer: a new treatment for positional obstructive sleep apnoea

Positional Treatment of Obstructive Sleep Apnea

Positional sleep apnea (POSA), a distinctive subtype of obstructive sleep apnea, underscores the critical influence of a patient's sleeping position on the severity of their condition. In the management of POSA, compliance with positional therapy (PT) is paramount, as it wields a profound impact on the treatment's efficacy and the overall alleviation of the disease. The advent of new-generation PT devices offers a promising alternative to conventional methods like the tennis ball technique, boasting higher compliance rates and substantial disease alleviation.

Efficacy of vibrotactile positional therapy devices on patients with positional obstructive sleep apnoea: a systematic review and meta-analysis

INTRODUCTION

Vibrotactile positional therapy (PT) devices are a new treatment modality for positional obstructive sleep apnoea (POSA). This review aimed to determine the effect of vibrotactile PT on the Apnoea Hypopnoea Index (AHI) and the percentage of time spent in the supine position (%Tsupine) in patients with POSA, compared with baseline. Secondary aims were to investigate the effect on daytime sleepiness, quality of life and sleep quality.

METHODS

A systematic review and meta-analysis was performed of randomised controlled trials (RCTs) and cohort studies that investigated the effect of vibrotactile PT in POSA patients. Searches were performed via MEDLINE, CENTRAL and Embase up to 29 October 2022.

RESULTS

1119 studies were identified, 18 studies met the inclusion criteria (10 RCTs, 8 cohort studies). The use of vibrotactile PT significantly reduced the AHI at follow-up compared with baseline (mean difference (95% CI) -9.19 events/hour (-11.68 to -6.70); p<0.00001). The mean %Tsupine was also significantly reduced (mean difference (95% CI) -32.79% (-38.75% to -26.83%); p<0.00001). The percentage changes in the AHI and %Tsupine were 43% and 70%, respectively. Secondary outcomes were daytime sleepiness, quality of life and sleep indices. These showed minimal change, although follow-up was short.

CONCLUSION

Vibrotactile PT devices are effective in treating POSA; reducing both AHI and %Tsupine. The effect on sleep quality, daytime sleepiness and disease-specific quality of life was minimal. However, there were limited data and follow-up was often brief, meaning that further research is needed to determine the effect of vibrotactile PT on patient-centred outcomes.

PROSPERO REGISTRATION NUMBER

CRD42020188617.

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.

Patient compliance and satisfaction with a new forehead device for positional obstructive sleep apnoea treatment: a post hoc analysis of a randomised controlled trial

BACKGROUND

The influence of body position in obstructive sleep apnoea patients is well known. A positional therapy device placed at the forehead has proven to be effective in reducing the severity of positional obstructive sleep apnoea (POSA) symptoms. The aim of the study was to evaluate patients' therapy compliance and satisfaction in the short term and mid-term.

METHODS

A post hoc analysis of a randomised controlled trial was conducted using an inactive device (ID) or an active device (AD) for 3 months. The primary outcomes were device usage and the percentage of patients with good compliance (defined as device use for more than 4 hours per night and more than 70% of nights per week). Secondary outcomes included time spent with head in the supine position, patient satisfaction and side effects.

RESULTS

The median duration of using the device was 6.9 hours in the ID group and 6.7 hours in the AD group (p=0.309), and the durations were similar throughout the follow-up period and from the first day of use. The percentage of patients with good compliance was similar and greater than 60% in both groups. The median time spent with head in the supine position was significantly lower in the AD group (2.9%) than in the ID group (12.4%) since the first day of treatment. Both groups showed satisfaction scores values above 8.5 (out of 10) in all items, while side effects were scarcely reported.

CONCLUSION

High device compliance was achieved in POSA patients, both in terms of device usage time and percentage of days used. Patients were highly satisfied, and the device effectively reduced the time spent with the head in the supine position from the first day of use.

Effects of the combination of novel eye mask sleep position therapy device and oral appliance on positional OSA: A multi-arm, parallel-group randomized controlled trial

OBJECTIVES

We explored whether a new combination of eye mask sleep position therapy (SPT) and oral appliance therapy (OAT) was more effective at treating positional obstructive sleep apnea (POSA) than was the use of either device alone.

METHODS

In this randomized controlled trial, 60 POSA subjects diagnosed by standard polysomnography (PSG) were divided into three groups (ratio 1:1:1): SPT, OAT, and SPT combined with OAT (SOT). Participants underwent hospital-based follow-ups during months 1 and 6 after beginning treatment. The primary outcome was the decline in the apnea hypopnea index (AHI) at month 6. The secondary outcomes were changes in oxygen-derived parameters and the curative effect at month 6.

RESULTS

After 6 months of treatment, PSG showed that SPT, OAT, and SOT all improved the AHI and oxygen-derived parameters. The AHI decline was significantly better in the SOT group than in the OAT or SPT group (71.58% [50.56-84.84%] for SOT, 44.42% [21.23-67.52%] for OAT, and 33.24% [19.03-54.62%] for SPT at 6 months) (P = 0.018 and P < 0.001 for the comparisons of SOT with OAT and SOT with SPT, respectively). In terms of oxygen-derived parameters, only the sleep apnea-specific hypoxic burden (SASHB) improved more in the SOT group (76.89% [57.43-85.91%]) than in the other groups (44.73% [32.38-72.69%] for OAT and 41.82% [15.40-65.24%] for SPT, P = 0.002 and P < 0.001 for the comparisons of SOT with OAT and SOT with SPT, respectively). The efficacies of SPT, OAT, and SOT were 36.84%, 50%, and 80% at 6 months; the SOT group evidenced the highest value (rate ratio [95% confidence interval] 1.78 (1.05-3.03), P = 0.048 and 2.17 (1.16-4.07), P = 0.010, for the comparisons of SOT with OAT and SOT with SPT, respectively).

CONCLUSION

The combination of SPT and OAT was better than either treatment alone and may represent a good option for the treatment of POSA.

TRIAL REGISTRATION

Chinese Clinical Trial Registry; URL: http://www.chictr.org.cn/showproj.aspx?proj=42,852; No. ChiCTR1900025584.

The effect of wearable-delivered sleep interventions on sleep outcomes among adults: A systematic review and meta-analysis of randomized controlled trials

The aims of the review were to (i) evaluate the effectiveness of wearable-delivered sleep interventions on sleep outcomes among adults, and (ii) explore the effect of factors affecting total sleep time. Eight databases were searched to identify relevant studies in English from inception until December 23, 2021. The Cochrane Risk of Bias tool version 2.0 and Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) criteria were used to assess the risk of bias and certainty of the evidence, respectively. Twenty randomized controlled trials (RCTs) were included, involving 1608 adults across nine countries. Wearable-delivered sleep interventions elicited significant improvement of 1.96 events/h for the oxygen desaturation index and 3.13 events/h for the respiratory distress index. Meta-analyses found that wearable-delivered sleep interventions significantly decreased sleep disturbance (Hedges' g [g] = -0.37, 95% confidence interval [CI]: -0.59, -0.15) and sleep-related impairment (g = -1.06, 95% CI: -1.99, -0.13) versus the comparators. The wearable-delivered sleep interventions may complement usual care to improve sleep outcomes. More rigorous RCTs with a long-term assessment in a wide range of populations are warranted.

Successful treatment of sleep paralysis with the Sleep Position Trainer: a case report

Sleep paralysis is a period of paralysis at either sleep onset or upon awakening and is often accompanied by terrifying hallucinations. We report a case of a 32-year-old healthy men with a history of mild positional obstructive sleep apnea and sleep paralysis. The positional sleep apnea was successfully treated with the Sleep Position Trainer. Remarkably, he did no longer experience episodes of sleep paralysis since using the Sleep Position Trainer. This case highlights a possible elegant noninvasive long-term solution for the treatment of sleep paralysis.

CITATION

Cui N, van Looij MA, Kasius KM. Successful treatment of sleep paralysis with the Sleep Position Trainer: a case report. J Clin Sleep Med. 2022;18(9):2317-2319.

Persistent OSA in obese children: does body position matter?

STUDY OBJECTIVES

The objective of this study was to determine if positional therapy is a viable treatment alternative for obese children with persistent obstructive sleep apnea (OSA).

METHODS

A retrospective review was performed of children who underwent an adenotonsillectomy for OSA from 2014 to 2017. Children were included if they had a body mass index ≥ 95th percentile and underwent a postoperative polysomnogram. Subjects fell into one of three categories: mixed sleep (the presence of ≥ 30 minutes of both nonsupine and supine sleep), nonsupine sleep, and supine sleep. Cure was defined as an OSA/apnea-hypopnea index of < 1 events/h. Paired t tests were used to assess the differences, and a linear model adjusting for obesity class, age at procedure, and sex was performed to assess the differences between nonsupine and supine sleep.

RESULTS

There were 154 children who met the inclusion criteria. Using a paired t test, supine sleep position had a significantly higher average OSA/apnea-hypopnea index (7.9 events) compared with nonsupine (OSA/apnea-hypopnea index of 4.1); P value was < .01 for the 60 children with mixed sleep. Forty-three children had predominantly nonsupine sleep and 33 predominantly supine sleep, and a McNemar's test comparing these children showed that those sleeping in the nonsupine position were significantly more likely to be cured than those in the supine position (P < .001).

CONCLUSIONS

Sleep physicians and otolaryngologists should be cognizant of positional treatment when consulting with families and note that the postoperative polysomnography may be inaccurate if it does not include supine sleep. Positional therapy as a potential treatment option for obese children with persistent OSA after adenotonsillectomy warrants further investigation.

Efficacy and long-term follow-up of positional therapy by vibrotactile neck-based device in the management of positional OSA

STUDY OBJECTIVES

Different therapeutic strategies have been investigated for the treatment of positional obstructive sleep apnea, but more evidence is needed about efficacy and compliance. The objective of this study was to describe the efficacy of vibrotactile neck-based treatment in patients with positional obstructive sleep apnea with different degrees of obstructive sleep apnea severity who were followed for 6 months.

METHODS

This is a retrospective study including 162 patients with positional obstructive sleep apnea undergoing vibrotactile neck-based positional therapy. We compared polysomnographic data obtained at baseline and during positional therapy after 1 month. We performed a subgroup analysis based on obstructive sleep apnea severity. Furthermore, we analyzed follow-up data in 84/162 (51.8%) patients with particular focus on discontinuation and complications related to the device.

RESULTS

We observed a significant difference between mean baseline obstructive apnea-hypopnea index (OAHI; 21.9 ± 9.9 events/h) and during positional therapy (12 ± 9.2 events/h; P < .01). Moreover, 87/162 (54.9%) patients showed a reduced baseline OAHI of at least 50% and 38/162 (23.4%) achieved complete disease control (OAHI < 5 events/h). At subgroup analysis, at least 50% reduction from baseline OAHI was observed in 56.8% of patients with mild, 55% with moderate, and 47.4% with severe OAHI, whereas complete control of disease was achieved in 50% of patients with mild, 22.5% with moderate, and 7.9% with severe OAHI. At a 6-month follow-up, only 35/84 patients (41.6%) were regularly using the device, with a mean of 5.9 ± 1.2 days per week.

CONCLUSIONS

Our results on the efficacy and long-term adherence to vibrotactile neck-based positional therapy showed that positional therapy can be an efficient first-line treatment option for mild positional obstructive sleep apnea and in selected cases of moderate disease. Long-term compliance is limited because of complications and low satisfaction in some patients.

New forehead device in positional obstructive sleep apnoea: a randomised clinical trial

RATIONALE

Approximately 60% of the patients with obstructive sleep apnoea suffer from a positional effect, and approximately 25% of these patients present events only in the supine position.

OBJECTIVE

To validate a new positional vibrating device and evaluate its efficacy in reducing the Apnoea-Hypopnoea Index and the total sleep time in the supine position without disturbing sleep.

METHODS

A total of 128 patients were recruited for this multicentre, prospective, parallel, randomised controlled trial and were distributed in three arms (general recommendations, inactive and active device). Full overnight polysomnography was performed at baseline and at 12 weeks. Anthropometric variables and sleep and quality of life questionnaires were collected at 4, 8 and 12 weeks.

RESULTS

The Apnoea-Hypopnoea Index decreased from 30.6 per hour to 20.4 per hour (p<0.001) in the active device (AD) group. In this group the reduction was 2.3-fold and 3.3-fold than the ones in the general recommendations (GR) and inactive device (ID) groups, respectively (p=0.014). Sleep time in supine position decreased 17.7%±26.3% in GR group (p<0.001), 13.0%±22.4% with ID group (p<0.001) and 21.0%±25.6% in the AD group (p<0.001). Furthermore, total sleep time increased significantly only in the AD group (22.1±57.5 min, p=0.016), with an increased percentage of time in the N3 (deep sleep) and N3+REM (rapid eye movement) stages, without sleep fragmentation.

CONCLUSION

The device was effective in reducing the Apnoea-Hypopnoea Index and time spent in the supine position also in improving sleep architecture. Therefore, the device could be a good option for the management of patients with positional obstructive sleep apnoea.

TRIAL REGISTRATION DETAILS

The trial was registered at www.clinicaltrials.gov (NCT03336515).

Influence of head flexion and rotation on obstructive sleep apnea severity during supine sleep

Head posture influences the collapsibility of the passive upper airway during anaesthesia. However, little is known about the impact of head posture during sleep. The objective of this study was to develop and validate an instrument to measure head posture during supine sleep and to apply this instrument to investigate the influence of head posture on obstructive sleep apnea (OSA) severity. A customized instrument to quantify head flexion and rotation during supine sleep was developed and validated in a benchtop experiment. Twenty-eight participants with suspected OSA were successfully studied using diagnostic polysomnography with the addition of the customized instrument. Head posture in supine sleep was discretized into four categories by two variables: head flexed or not (flexion >15°); and head rotated or not (rotation >45°). Sleep time in each posture and the posture-specific apnea-hypopnea index (AHI) were quantified. Linear mixed-effect modelling was applied to determine the influence of flexion and rotation on supine OSA severity. Twenty-four participants had ≥15 min of supine sleep in at least one head-posture category. Only one participant had ≥15 min of supine sleep time with the head extended. Head flexion was associated with a 12.9 events/h increase in the AHI (95% CI: 3.7-22.1, p = .007). Head rotation was associated with an 11.0 events/h decrease in the AHI (95% CI: 0.3-21.6, p = .04). Despite substantial interparticipant variability, head flexion worsened OSA severity, and head rotation improved OSA severity. Interventions to promote rotation and restrict flexion may have therapeutic benefit in selected patients.

Standardized framework to report on the role of sleeping position in sleep apnea patients

PURPOSE

Sleep apnea is a multifactorial illness which can be differentiated in various physiological phenotypes as a result of both anatomical and non-anatomical contributors (e.g., low respiratory arousal threshold, high loop gain). In addition, the frequency and duration of apneas, in the majority of patients with OSA, are influenced by sleeping position. Differences in characteristics between non-positional patients (NPP) and positional patients (PP) suggest another crucial phenotype distinction, a clinical phenotype focusing on the role of sleeping position on sleep apnea. Since this clinical phenotype distinction has therapeutic implications, further research is necessary to better understand the pathophysiology behind this phenotypic trait and to improve management of PP. Therefore, we suggest a standardized framework that emphasizes the role of sleeping position when reporting clinical and research data on sleep apnea.

METHODS

We identified 5 key topics whereby a standardized framework to report on the role of sleeping position would be of added value: (1) sleep study data, (2) anatomical, morphological and physiological factors, (3) drug-induced sleep endoscopy (DISE) findings, (4) sleep apnea management, and (5) effectiveness versus efficacy of positional therapy in sleep apnea management. We performed a literature search to identify evidence to describe and support the rationale behind these 5 main recommendations.

RESULTS

In this paper, we present the rationale behind this construct and present specific recommendations such as reporting sleep study indices (disease severity) and sleep time spent in various sleeping positions. The same is suggested for DISE findings and effect of treatment. Sleep study indices (disease severity), anatomical, morphological, and physiological factors in sleep apnea patients should be reported separately for PP and NPP.

CONCLUSION

Applying these suggestions in future research will improve patient care, assist in better understanding of this dominant phenotype, and will enhance accurate comparisons across studies and future investigations.

Positional Therapy for Positional Obstructive Sleep Apnea

Positional therapy appears to be an attractive strategy for many patients with positional obstructive sleep apnea (OSA). However, under the American Academy of Sleep Medicine OSA guidelines, positional therapy is considered as only an alternative therapy, because previous research has demonstrated poor treatment tolerance and adherence. Recent technological advances have renewed interest in positional therapy, with the invention of new sophisticated vibratory positional therapy devices. These devices have shown great promise with efficacy, markedly improved patient tolerance, and long-term adherence. We review the literature on positional therapy and explore the most current evidence on the new positional therapy devices.

Comparing treatment effects of a convenient vibratory positional device to CPAP in positional OSA: a crossover randomised controlled trial

OBJECTIVES

Up to 77% of patients with obstructive sleep apnoea (OSA) have positional OSA (POSA) but traditional positional therapy (PT) methods have failed as they were poorly tolerated. New convenient vibratory PT devices have been invented but while recent studies suggest high treatment efficacy and adherence, there are no published data comparing these devices directly with continuous positive airway pressure (CPAP). Our objective is to evaluate if a convenient vibratory PT device is non-inferior to CPAP in POSA treatment.

METHODS

In this crossover randomised controlled trial, we enrolled patients with POSA with significant daytime sleepiness (Epworth Sleepiness Scale (ESS)≥10). POSA diagnosis was based on: (1) total Apnoea/Hypopnoea Index (AHI)>10/hour and non-supine AHI<10/hour (2) supine AHI≥2 × non-supine AHI. Patients used their initial allocated devices (PT or CPAP) for 8 weeks before crossing to the alternative intervention after a 1 week washout. The primary aim is to measure changes in ESS between the two treatments. Secondary outcomes include sleep study parameters and patient treatment preference (ClinicalTrials.gov: NCT03125512).

RESULTS

40 patients completed the trial between April 2017 and December 2018. Difference in ESS after 8 weeks of device use (PT minus CPAP) was 2.0 (95% CI 0.68 to 3.32), exceeding our predetermined non-inferiority margin of 1.5. AHI on CPAP was lower than with PT (4.0±3.2 vs 13.0±13.8 events/hour, respectively, p=0.001), although both were lower than at baseline. Time spent supine was significantly lower with PT than CPAP (p<0.001). 60% of patients preferred CPAP, 20% preferred PT, while 20% preferred neither device.

CONCLUSIONS

The non-inferiority ESS endpoint for PT compared with CPAP was not met and the results were inconclusive. Future trials with larger sample sizes or in less symptomatic patients are warranted to provide further insight into the role of these new vibratory PT devices.

Positional obstructive sleep apnoea: challenging findings in consecutive patients treated with a vibrating position trainer

OBJECTIVES

Last years, vibrating devices were introduced to treat positional sleep apnoea (POSA). However, few data exist on determinants of effectiveness and adherence in clinical settings. Methods: The NightBalance Sleep Position Trainer (SPT) analyses the patient's position during the first 2 nights, starts to build up vibrations during the following 7 and is 100% performant from night 10 on; and, reports on %supine, usage time, number of (responses on) vibrations. The device was started for a 28-day try-out period in a clinical cohort of 51 consecutive patients with POSA. SPT-stored data were studied on different time points: first 2 nights without vibrations (baseline), first 2 nights on SPT 100% performance (short term) and 2 later nights after having used the full performant device for 14 days (long term). Results: Only 27 patients used the device throughout the long-term period. The baseline %supine was lower than during polysomnography: 22.9 ± 16.2 versus 40.7 ± 20.0% (p = 0.0005). Apnoea-hypopnoea index calculation taking into account the %supine on SPT revealed that 2/27 patients would not have obstructive sleep apnoea at home. The baseline %supine dropped (p < 0.0001) on short term without further change on long term. Ten patients could be considered cured and demonstrated higher response on vibrations. Only 29 patients could be considered as adherent, and they demonstrated higher response on vibrations and less side effects; only 13 wanted to purchase the SPT. Conclusion: On polysomnography, the %supine is overestimated. The efficacy and low adherence are influenced by differences in response to vibrations. The training effect is already presented on short term.

[Non-surgical treatment of the sleep related breathing disorders in adults]

The treatment of obstructive sleep apnoea/hypopnoea syndrome (OSAHS) must allow for the suppression of symptoms and also prevent its immediate and long-term consequences. The evaluation of the effectiveness of treatments is now based on a normal apnea/hypopnea index, a normal oxygen saturation and the disappearance of sleep fragmentation. Clinical and biological follow-up of co-morbidities must be ensured. Compliance with treatment, a major element of success, must be monitored. Continuous Positive Airway Pressure (CPAP) is still the most effective and widely used treatment. However, mandibular advancement orthosis is now recommended as a first-line treatment in moderate forms in the absence of severe cardiovascular comorbidities (CV) and remains a therapeutic alternative in the event of refusal or intolerance to CPAP. Nutritional management in cases of obesity and a physical activity program must be systematically offered. A reduction in nocturnal breathing disorders can also be achieved by using a device in the event of positional OSAHS, or by limiting fluid movements. The contribution of myofunctional therapy is currently being evaluated. Very recently, a study testing the efficiency of pharmacological treatment on the severity of OSAHS and the reactivity of geniogloss appears to be promising. The evaluation of these different treatments and their combination should make it possible to evolve towards a personalised management adapted to each patient.

Polysomnography and sleep position, a Heisenberg phenomenon? : A large-scale series

BACKGROUND

The severity of position-dependent obstructive sleep apnea (POSA) depends on the nonsupine and supine apnea-hypopnea index (AHI) as well as the time spent in supine position. The latter in particular is susceptible to variation. Several small-scale studies suggest that wearing polysomnography (PSG) apparatus leads to an increase in supine sleeping position.

OBJECTIVES

The aim of this study was to evaluate the effect of wearing PSG apparatus on sleeping position and on OSA severity.

MATERIAL AND METHODS

A large-scale, retrospective study was performed, including a consecutive series of POSA and non-apneic snoring patients who were prescribed positional therapy (Sleep Position Trainer [SPT]). The effect of wearing PSG apparatus on sleeping position was evaluated by comparing body position during the PSG night and inactive (diagnostic) phase of SPT.

RESULTS

The mean percentage of total recording time (TRT) in supine position was 43.1% during the PSG night phase compared with 28.6% of TRT during the inactive (diagnostic) phase of SPT; i.e., a significant decrease of 33.6% (p < 0.001). When adjusting the AHI using TRT in different sleeping positions measured with the SPT, the median AHI decreased from 13.3/h (9.0-20.4) to 10.3/h (6.8-16.2); p < 0.001. When using the adjusted AHI, 33% (N = 66) of all patients had a change in OSA severity.

CONCLUSIONS

The results of this study indicate that wearing PSG apparatus leads to an increase in the percentage of supine sleeping position causing an overestimation of OSA severity, especially in patients with POSA. This can have significant impact on both clinical and scientific practice.

The influence of position-dependency on surgical success in sleep apnea surgery - a systematic review

PURPOSE

To evaluate the influence of position-dependency on surgical success of upper airway (UA) surgery in obstructive sleep apnea (OSA) patients.

METHODS

Systematic review.

RESULTS

Two prospective cohort studies and seven retrospective cohort studies were included in this review. Despite the importance of the subject, it remains unclear whether position-dependency is a predictor for surgical success. No differences were found in surgical success rate between non-positional (NPP) and positional (PP) OSA patients undergoing uvulopalatopharyngoplasty/Z-palatoplasty with or without radiofrequent thermotherapy of the tongue, isolated tongue base or multilevel surgery and hypoglossal nerve stimulation. In one study PP undergoing relocation pharyngoplasty had a greater chance of surgical success. In the majority of the remaining studies, surgical success was in favor of NPP. Furthermore, in the vast part of included studies, the effect of UA surgery was suggested to be greater in the lateral position than supine position.

CONCLUSION

Although preoperative characteristics in PP (e.g., lower BMI and AHI) seem to be in favor for higher surgical success compared to NPP, it remains unclear whether position-dependency is a predictor for surgical outcome. It is suggested that the largest differences and expected preoperative and postoperative changes occur in non-supine AHI. In PP, the preoperative non-supine AHI is already lower compared to NPP suggesting a lower chance of surgical success in PP.

MRI-based methodology to monitor the impact of positional changes on the airway caliber in obstructive sleep apnea patients

PURPOSE

To develop a non-invasive MRI-based methodology to visually and quantitatively assess the impact of head and chest rotations on the airway caliber.

METHODS

An MRI table set-up was developed for independent rotations of the head and chest along B₀ field and tested for feasibility using phantom scans. The accuracy of the head and chest rotations was validated with ten volunteer scans. A 3T MRI protocol was optimized to image the regions of interest (ROIs) that were the retropalatal (RP) and retroglossal (RG) sections of the upper airway. A workflow for data analysis was developed to assess the changes of the airway caliber following the independent head and chest rotations.

RESULTS

A prototype MRI table setup was established with two separate plates each supporting and rotating the head or chest independently. Subject positioning and image acquisition were finished within seven minutes for each position. Thus, each subject MRI was set up with seven positions and completed for less than one hour. The implemented angles were within 0.3-degree deviation from the targeted angles. The data analysis workflow provided 2D and 3D visualization and quantification with the measurements of cross-sectional area, lateral and anterior-posterior distances of the ROIs. Sharp contrast of the airway and its surrounding tissues facilitated an automatic approach to ROI placement to minimize subjectivity.

CONCLUSIONS

The 3T MRI data acquisition and analysis methodology could reliably assess the impact of head and chest rotations on the upper airway caliber to identify the optimal position for obstructive sleep apnea patients.

The Ghana PrenaBelt trial: a double-blind, sham-controlled, randomised clinical trial to evaluate the effect of maternal positional therapy during third-trimester sleep on birth weight

OBJECTIVE

To evaluate the effect, on birth weight and birth weight centile, of use of the PrenaBelt, a maternal positional therapy device, during sleep in the home setting throughout the third trimester of pregnancy.

DESIGN

A double-blind, sham-controlled, randomised clinical trial.

SETTING

Conducted from September 2015 to May 2016, at a single, tertiary-level centre in Accra, Ghana.

PARTICIPANTS

Two-hundred participants entered the study. One-hundred-eighty-one participants completed the study. Participants were women, 18 to 35 years of age, with low-risk, singleton, pregnancies in their third-trimester, with body mass index <35 kg/m² at the first antenatal appointment for the index pregnancy and without known foetal abnormalities, pregnancy complications or medical conditions complicating sleep.

INTERVENTIONS

Participants were randomised by computer-generated, one-to-one, simple randomisation to receive either the PrenaBelt or sham-PrenaBelt. Participants were instructed to wear their assigned device to sleep every night for the remainder of their pregnancy (approximately 12 weeks in total) and were provided a sleep diary to track their use. Allocation concealment was by unmarked, security-tinted, sealed envelopes. Participants and the outcomes assessor were blinded to allocation.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcomes were birth weight and birth weight centile. Secondary outcomes included adherence to using the assigned device nightly, sleeping position, pregnancy outcomes and feedback from participants and maternity personnel.

RESULTS

One-hundred-sixty-seven participants were included in the primary analysis. The adherence to using the assigned device nightly was 56%. The mean ±SD birth weight in the PrenaBelt group (n=83) was 3191g±483 and in the sham-PrenaBelt group (n=84) was 3081g±484 (difference 110 g, 95% CI -38 to 258, p=0.14). The median (IQR) customised birth weight centile in the PrenaBelt group was 43% (18 to 67) and in the sham-PrenaBelt group was 31% (14 to 58) (difference 7%, 95% CI -2 to 17, p=0.11).

CONCLUSIONS

The PrenaBelt did not have a statistically significant effect on birth weight or birth weight centile in comparison to the sham-PrenaBelt.

TRIAL REGISTRATION NUMBER

NCT02379728.

Positional Therapy for Positional Obstructive Sleep Apnea

Positional therapy appears to be an attractive strategy for many patients with positional obstructive sleep apnea (OSA). However, under the American Academy of Sleep Medicine OSA guidelines, positional therapy is considered as only an alternative therapy, because previous research has demonstrated poor treatment tolerance and adherence. Recent technological advances have renewed interest in positional therapy, with the invention of new sophisticated vibratory positional therapy devices. These devices have shown great promise with efficacy, markedly improved patient tolerance, and long-term adherence. We review the literature on positional therapy and explore the most current evidence on the new positional therapy devices.

Treatment of sleep-disordered breathing with positional therapy: long-term results

PURPOSE

The aim of the present study was to assess the efficacy of a sleep position trainer (SPT) in patients with an established diagnosis of positional obstructive sleep apnea and to evaluate the adherence after 1-year follow-up.

METHODS

Polysomnography (PSG) was performed at baseline and after 1 year of SPT use. Patients received questionnaires to assess treatment satisfaction and subjective adherence. Data on objective adherence and number of vibrations initiated by the SPT were collected from the SPT device.

RESULTS

Nine out of 58 patients stopped using the SPT during the first year of treatment (16%). Thirty-four middle-aged and overweight patients underwent a PSG after 1 year of SPT use (male/female ratio, 28/6; overall apnea/hypopnea index (AHI), 16/h). A significant reduction in overall AHI to 6/h was observed using treatment (p < 0.001). The median percentage of supine sleep decreased significantly to 1% with SPT (p < 0.001). The mean objective SPT use in 28 patients was 7.3 ± 0.9 h/night and 69 ± 26% of the nights. Furthermore, 75% of the patients reported a better sleep quality since the start of SPT treatment.

CONCLUSIONS

Long-term treatment with the SPT was found to be effective in reducing overall AHI. Time spent sleeping in supine position was reduced to almost zero in the continuing users. Patient satisfaction was high when using the SPT.

Successful upper airway stimulation therapy in an adult Down syndrome patient with severe obstructive sleep apnea

PURPOSE

The aim of this study was to report on the successful application of upper airway stimulation (UAS) therapy in an adult Down syndrome (DS) patient with severe obstructive sleep apnea (OSA) and continuous positive airway pressure (CPAP) intolerance.

METHODS

Baseline polysomnography (PSG) in a 23-year-old male OSA patient (body mass index (BMI) 24.4 kg/m²) revealed an apnea/hypopnea index (AHI) of 61.5 events/h and oxygen desaturation index (ODI) of 39.7 events/h. Based on the clinical examination, PSG and drug-induced sleep endoscopy, the patient fulfilled the formal inclusion criteria for UAS therapy: AHI between 15 and 65 events/h, BMI < 32 kg/m², and no complete concentric collapse at the level of the velopharynx.

RESULTS

Implantation of the hypoglossal nerve stimulator in the adult patient with DS resulted in a substantial subjective as well as objective improvement of OSA (63 to 81% decrease in AHI and 77% decrease in ODI), translating into an overall satisfactory outcome.

CONCLUSION

Research on the long-term effectiveness of UAS therapy in a larger group of patients with DS is needed. However, based on the available literature and our presented case, respiration-synchronized electrostimulation of the hypoglossal nerve using UAS therapy may have a potential value in well-selected OSA patients with DS who are non-compliant to CPAP therapy.

Drug-induced sleep endoscopy: the effect of different passive maneuvers on the distribution of collapse patterns of the upper airway in obstructive sleep apnea patients

PURPOSE

To evaluate the effect of different passive maneuvers (lateral head rotation and jaw thrust) during drug-induced sleep endoscopy (DISE) on distribution of collapse patterns at the level of velum, oropharynx, tongue base, and epiglottis (VOTE).

METHODS

Retrospective, single-center cohort study. Patients diagnosed with OSA who underwent DISE between August 2016 and February 2017 were included. During DISE procedure lateral head rotation, jaw thrust and a combination of both were applied and scored by VOTE obstruction level. Also, the effect of these maneuvers was analyzed for complete concentric collapse (CCC) versus complete non-concentric collapse (CNCC) subgroups.

RESULTS

Two hundred patients were included (161 male (80.5%), mean age 50.1 ± 11.7 years, median AHI 19.2 (11.7, 31.0) events/h). For lateral head rotation, significant improvement in upper airway collapse at all levels was observed, with exception of the level of the oropharynx, where an increase in obstruction was seen. Jaw thrust resulted in a significant decrease of collapse on all four VOTE levels. The CCC group responded similarly to the CNCC group when only one maneuver was applied, but the CCC group showed less improvement when both maneuvers were combined.

CONCLUSIONS

This study gives new insights into the changes in distribution of collapse patterns when passive maneuvers are applied during DISE. Jaw thrust and lateral head rotation gave improvement of obstruction mostly in line with previous research. The CNCC and CCC groups responded similarly to application of a single maneuver, but there was a significant difference found when both maneuvers were combined.

Modifying maternal sleep position in the third trimester of pregnancy with positional therapy: a randomised pilot trial

OBJECTIVE

To evaluate whether the percentage of time spent supine during sleep in the third trimester of pregnancy could be reduced using a positional therapy device (PrenaBelt) compared with a sham device.

DESIGN

A double-blind, randomised, sham-controlled, cross-over pilot trial.

SETTING

Conducted between March 2016 and January 2017, at a single, tertiary-level centre in Canada.

PARTICIPANTS

23 participants entered the study. 20 participants completed the study. Participants were low-risk, singleton, third-trimester pregnant women aged 18 years and older with body mass index <35 kg/m² at the first antenatal appointment for the index pregnancy and without known fetal abnormalities, pregnancy complications or medical conditions complicating sleep.

INTERVENTIONS

A two-night, polysomnography study in a sleep laboratory. Participants were randomised by computer-generated, one-to-one, simple randomisation to receive either a PrenaBelt or a sham-PrenaBelt on the first night and were crossed over to the alternate device on the second night. Allocation concealment was by unmarked, security-tinted, sealed envelopes. Participants, the recruiter and personnel involved in setting up, conducting, scoring and interpreting the polysomnogram were blinded to allocation.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome was the percentage of time spent supine during sleep. Secondary outcomes included maternal sleep architecture, respiration, self-reported sleep position and feedback.

RESULTS

The median percentage of sleep time supine was reduced from 16.4% on the sham night to 3.5% on the PrenaBelt night (pseudomedian=5.8, p=0.03). We were unable to demonstrate differences in sleep architecture or respiration. Participants underestimated the time they spent sleeping supine by 7.0%, and six (30%) participants indicated they would make changes to the PrenaBelt. There were no harms in this study.

CONCLUSIONS

This study demonstrates that the percentage of sleep time supine during late pregnancy can be significantly reduced via positional therapy.

TRIAL REGISTRATION NUMBER

NCT02377817; Results.

Subjective effects of the sleep position trainer on snoring outcomes in position-dependent non-apneic snorers

Purpose

To evaluate the effect of a new-generation positional device, the sleep position trainer (SPT), in non-apneic position-dependent snorers.

Methods

Non-apneic position-dependent snorers with an apnea–hypopnea index (AHI) < 5 events/h were included between February 2015 and September 2016. After inclusion, study subjects used the SPT at home for 6 weeks. The Snore Outcome Survey (SOS) was filled out by the subjects at baseline and after 6 weeks, and at the same time, the Spouse/Bed Partner Survey (SBPS) was filled out by their bed partners.

Results

A total of 36 participants were included and 30 completed the study. SOS score improved significantly after 6 weeks from 35.0 ± 13.5 to 55.3 ± 18.6, p < 0.001. SBPS score also improved significantly after 6 weeks from 24.7 ± 16.0 versus 54.5 ± 25.2, p < 0.001. The severity of snoring assessed with a numeric visual analogue scale (VAS) by the bed partner decreased significantly from a median of 8.0 with an interquartile range (IQR) of [7.0–8.5] to 7.0 [3.8–8.0] after 6 weeks (p = 0.004).

Conclusions

Results of this study indicate that positional therapy with the SPT improved several snoring-related outcome measures in non-apneic position-dependent snorers. The results of this non-controlled study demonstrate that this SPT could be considered as an alternative therapeutic option to improve sleep-related health status of snorers and their bed partners.

Durability of treatment effects of the Sleep Position Trainer versus oral appliance therapy in positional OSA: 12-month follow-up of a randomized controlled trial

PURPOSE

The Sleep Position Trainer (SPT) is a new option for treating patients with positional obstructive sleep apnea (POSA). This study investigated long-term efficacy, adherence, and quality of life during use of the SPT device compared with oral appliance therapy (OAT) in patients with POSA.

METHODS

This prospective, multicenter trial randomized patients with mild to moderate POSA (apnea-hypopnea index [AHI] 5-30/h) to SPT or OAT. Polysomnography was performed at baseline and after 3 and 12 months' follow-up. The primary endpoint was OSA severity; adherence, quality of life, and adverse events were also assessed.

RESULTS

Ninety-nine patients were randomized and 58 completed the study (29 in each group). Median AHI in the SPT group decreased from 13.2/h at baseline to 7.1/h after 12 months (P < 0.001); corresponding values in the OAT group were 13.4/h and 5.0/h (P < 0.001), with no significant between-group difference (P = 1.000). Improvements throughout the study were maintained at 12 months. Long-term median adherence was also similar in the two treatment groups; the proportion of patients who used their device for ≥ 4 h for 5 days in a week was 100% in the SPT group and 97.0% in the OAT group (P = 0.598).

CONCLUSIONS

The efficacy of SPT therapy was maintained over 12 months and was comparable to that of OAT in patients with mild to moderate POSA. Adherence was relatively high, and similar in the two groups.

TRIAL REGISTRATION

www.clinicaltrials.gov (NCT02045576).

Evaluation of a Trial Period With a Sleep Position Trainer in Patients With Positional Sleep Apnea

STUDY OBJECTIVES

To assess the overall clinical effectiveness of a sleep position trainer (SPT) in patients with positional obstructive sleep apnea (POSA) and to evaluate how many patients were willing to continue treatment after a 1-month trial period.

METHODS

Patients in whom POSA was diagnosed underwent a 1-month trial period with the SPT. Home sleep apnea tests were used to measure baseline data and data following the trial period with the SPT.

RESULTS

The 79 patients who completed the study protocol were 81% male, had a mean age of 52 ± 12 years, and a median baseline respiratory event index (REI) of 11 (8, 16) events/h. A significant reduction in overall REI to 5 (3, 10) events/h was observed with the SPT as compared to baseline (P < .001). The median percentage of sleep time in the supine position decreased significantly from 27 (20, 48) to 7 (2, 20) with the SPT (P < .001). Adherence was found to be 95 ± 8%. Of the 44 patients who decided to continue treatment, 27 were categorized as responders (having a decrease in REI of at least 50%) and 17 were non-responders. The most important reasons for not purchasing the SPT were poor objective results, intolerance to the vibrations, cost of the device, persistent daytime sleepiness, or patient preference for other treatment options.

CONCLUSIONS

Treatment with the SPT came with high adherence rates and was effective in reducing REI and supine sleep position. The trial period is in the patients' best interest, as it may prevent those who will not benefit from positional training from purchasing an SPT.

Prevalence and characteristics of positional sleep apnea in the HypnoLaus population-based cohort

OBJECTIVE/BACKGROUND

To determine the prevalence of positional obstructive sleep apnea (POSA) and exclusive POSA (ePOSA) in the general population and to assess the factors independently associated with POSA and ePOSA according to gender and menopausal status.

PATIENTS/METHODS

Participants of the population-based HypnoLaus Sleep Cohort underwent full polysomnography at home. POSA was defined as an apnea-hypopnea index (AHI) ≥5/h, and supine/non-supine AHI ratio (sAHI/nsAHI) ≥2 (ePOSA when non-supine AHI was normalized).

RESULTS

In this study, 1719 subjects (40-85y.o. 46% men) with at least 30 min spent in both the supine and non-supine positions were included. OSA was present in 1224 subjects (71%) (AHI >5/H). POSA was present in 53% of all subjects, and in 75% of OSA subjects. ePOSA was present in 26% of all subjects and in 36% of OSA subjects. In multivariate analyses, lower AHI and lower BMI were both associated with POSA and ePOSA in males. In premenopausal females, no single factor was associated with POSA while a lower AHI and an Epworth sleepiness scale >10 were associated with ePOSA. In postmenopausal women, a lower BMI was associated with POSA and a lower AHI and a lower Mallampati score with ePOSA.

CONCLUSIONS

In this large population-based study, we found that POSA is present in 53% of the middle-to-older age general population, and in 75% of OSA subjects. ePOSA was present in 36% of OSA subjects, suggesting that a large proportion of them could be treated with positional therapy. AHI and BMI were differently associated with POSA in men, and pre or post-menopausal women.

User Compliance and Behavioral Adaptation Associated With Supine Avoidance Therapy

This study investigates behavioral adaptation to vibrotactile position-avoidance therapy during sleep in patients with obstructive sleep apnea (n =135) across 15 to 52 weeks. The overall compliance, based on nights used ≥ 4 hr, was 71%. Overall regular use, that is, ≥ 4 hr/night over 70% of nights, was 88%. Poor early compliance strongly predicted poor long-term treatment adherence, with 92% of those noncompliant across the first 12 weeks of therapy remaining noncompliant. Conversely, 21% of those with compliant utilization in the short term became noncompliant in the long term. It appears that patients do not habituate to the stimulus during sleep, nor was there a training effect associated with long-term use.

Narrative review of contemporary treatment options in the care of patients with obstructive sleep apnoea

Snoring and obstructive sleep apnoea (OSA) are increasingly common conditions, and confer a significant health and socioeconomic burden. Furthermore, untreated OSA represents a significant mortality risk. Patients require careful assessment, including detailed clinical history and examination, sleep study and drug-induced sleep endoscopy (DISE). Although nasal continuous positive airway pressure (nCPAP) is the gold standard treatment for moderate and severe OSA, multidisciplinary team assessment is often required to develop the best treatment plan for an individual, especially when nasal CPAP is poorly tolerated. There is a wide range of medical and surgical treatment options, and following appropriate patient selection and assessment, a focused site-specific, often multilevel, intervention is indicated. There is an increasing body of evidence in the literature supporting these multilevel interventions and with agreement on standardized outcome measures more trials are likely to improve the robustness of these data further.

Recent developments in the diagnosis and treatment of obstructive sleep apnea : English version

Over the past few years, the diagnostic tools and therapeutic approaches for obstructive sleep apnea (OSA) have evolved further. Based on a review of the current literature and the personal experiences of the authors, the most relevant developments are summarized in this article and discussed with regard to their impact on the clinical management of the disease. In the third edition of the International Classification of Sleep Disorders, the classification of sleep-disordered breathing was modified. Notably, additional clinical criteria for the diagnosis of OSA were established and out-of-center sleep testing was introduced as an alternative to polysomnography. Recent technical advancements in diagnostic tools (e. g., peripheral arterial tonometry and pulse wave analysis) have further expanded the diagnostic possibilities. Drug-induced sleep endoscopy allows for a reliable assessment of the level and degree of upper airway obstruction. Whether this gain in diagnostic information leads to an improvement in surgical outcome is, however, still being discussed. The relevance of positional OSA has received increasing attention - the subgroup of patients in whom sleeping position significantly impacts their disease is reported to be above 50 %. For these patients, the introduction of the sleep position trainer offers a new therapeutic option. Further, hypoglossal nerve stimulation (upper airway stimulation) has substantially expanded the surgical spectrum for the treatment of OSA. In regard to the established surgical treatment options, randomized trials with superior methodology have been published, especially for bimaxillary advancement and tonsillectomy with uvulopalatopharyngoplasty. These developments are of particular interest for the otolaryngologist and will influence daily practice.

[Treatment of supine position-related obstructive sleep apnea with smartphone applications]

BACKGROUND

Positional obstructive sleep apnea (POSA) is common in mild and moderate forms of obstructive sleep apnea (OSA). Two smartphone applications (apps) professing to avoid the supine position (SP) are available: for Android the "Apnea Sleep Position Trainer" and for iOS the "SomnoPose-Sleep Position Monitor". The smartphone needs to be attached to the chest to recognize SP, which then triggers a vibration alarm. This is intended to encourage the patient to change position and the vibration stops as soon as SP is left. These apps, however, have not yet undergone a systematic evaluation.

METHODS

Adult patients with polysomnographically diagnosed POSA were invited to participate in the study. POSA was defined as an apnea-hypopnea index (AHI) in SP >10, with AHI in a lateral position <10 and doubling of the AHI in SP. After 1 month, a control polysomnography (PSG) was performed and compliance (at least 4 h/night on 5 of 7 days) was evaluated after 6 months by phone. A sufficient therapy was defined as reduction in SP to <10% of the total sleep time and to an overall AHI <10.

RESULTS

Although 57 patients entered the study, 24 did not appear to the PSG control; therefore, 33 patients finished the study, of whom 25 were treated successfully. The overall AHI in 33 patients was reduced from 14.5 ± 9.0 to 9.5 ± 12.6 and the time in SP decreased significantly from 71.1 ± 50.5 to 25.4 ± 65.0 min. Compliance among the 25 continuously treated patients after 6 months was 79.2%.

CONCLUSION

Both smartphone apps have the capability to prevent PS in POSA patients and can potentially offer a cost-effective option in the treatment of POSA.

Obstructive sleep apnea: in search of precision

Introduction

Obstructive sleep apnea (OSA) is a highly prevalent condition that is viewed as a major global health concern, while affecting approximately 10% of the middle-aged population. OSA is a chronic disease that has been conclusively associated with poor quality of life, cognitive impairments and mood alterations, enhanced cardiovascular and metabolic morbidity, thereby leading to marked increments in healthcare costs.

Areas covered

The authors have reviewed the current evidence on the pathophysiology of OSA and its consequences, the heterogeneity of its phenotypic expression, the current therapeutic applications and their efficacy, and the implications for diagnosis, treatment and follow-up strategies in the context of the clinical management of OSA.

Expert commentary

Personalized medicine in OSA identifies different needs and approaches: i) phenotyping and defining the different and segregated clusters of OSA patients whose recognition may improve prognostic predictions and guide therapeutic strategies; ii) to further characterize and predict the impact of OSA and its treatment, particularly revolving around mortality and the processes closely related to ageing (cardiovascular diseases, cancer and neurocognitive diseases); iii) the introduction of new technologies including telemedicine that have shown promise in the implementation of personalized medicine approaches.

Estimating sleep parameters using nasal pressure signals applicable to continuous positive airway pressure devices

OBJECTIVE

This paper proposes a method for classifying sleep-wakefulness and estimating sleep parameters using nasal pressure signals applicable to a continuous positive airway pressure (CPAP) device.

APPROACH

In order to classify the sleep-wakefulness states of patients with sleep-disordered breathing (SDB), apnea-hypopnea and snoring events are first detected. Epochs detected as SDB are classified as sleep, and time-domain- and frequency-domain-based features are extracted from the epochs that are detected as normal breathing. Subsequently, sleep-wakefulness is classified using a support vector machine (SVM) classifier in the normal breathing epoch. Finally, four sleep parameters-sleep onset, wake after sleep onset, total sleep time and sleep efficiency-are estimated based on the classified sleep-wakefulness. In order to develop and test the algorithm, 110 patients diagnosed with SDB participated in this study. Ninety of the subjects underwent full-night polysomnography (PSG) and twenty underwent split-night PSG. The subjects were divided into 50 patients of a training set (full/split: 42/8), 30 of a validation set (full/split: 24/6) and 30 of a test set (full/split: 24/6).

MAIN RESULTS

In the experiments conducted, sleep-wakefulness classification accuracy was found to be 83.2% in the test set, compared with the PSG scoring results of clinical experts. Furthermore, all four sleep parameters showed higher correlations than the results obtained via PSG (r  ⩾  0.84, p  <  0.05). In order to determine whether the proposed method is applicable to CPAP, sleep-wakefulness classification performances were evaluated for each CPAP in the split-night PSG data. The results indicate that the accuracy and sensitivity of sleep-wakefulness classification by CPAP variation shows no statistically significant difference (p  <  0.05).

SIGNIFICANCE

The contributions made in this study are applicable to the automatic classification of sleep-wakefulness states in CPAP devices and evaluation of the quality of sleep.

Effect of Sleeping Position on Upper Airway Patency in Obstructive Sleep Apnea Is Determined by the Pharyngeal Structure Causing Collapse

Objectives

In some patients, obstructive sleep apnea (OSA) can be resolved with improvement in pharyngeal patency by sleeping lateral rather than supine, possibly as gravitational effects on the tongue are relieved. Here we tested the hypothesis that the improvement in pharyngeal patency depends on the anatomical structure causing collapse, with patients with tongue-related obstruction and epiglottic collapse exhibiting preferential improvements.

Methods

Twenty-four OSA patients underwent upper airway endoscopy during natural sleep to determine the pharyngeal structure associated with obstruction, with simultaneous recordings of airflow and pharyngeal pressure. Patients were grouped into three categories based on supine endoscopy: Tongue-related obstruction (posteriorly located tongue, N = 10), non-tongue related obstruction (collapse due to the palate or lateral walls, N = 8), and epiglottic collapse (N = 6). Improvement in pharyngeal obstruction was quantified using the change in peak inspiratory airflow and minute ventilation lateral versus supine.

Results

Contrary to our hypothesis, patients with tongue-related obstruction showed no improvement in airflow, and the tongue remained posteriorly located while lateral. Patients without tongue involvement showed modest improvement in airflow (peak flow increased 0.07 L/s and ventilation increased 1.5 L/min). Epiglottic collapse was virtually abolished with lateral positioning and ventilation increased by 45% compared to supine position.

Conclusions

Improvement in pharyngeal patency with sleeping position is structure specific, with profound improvements seen in patients with epiglottic collapse, modest effects in those without tongue involvement and-unexpectedly-no effect in those with tongue-related obstruction. Our data refute the notion that the tongue falls back into the airway during sleep via gravitational influences.

Efficacy of the New Generation of Devices for Positional Therapy for Patients With Positional Obstructive Sleep Apnea: A Systematic Review of the Literature and Meta-Analysis

STUDY OBJECTIVES

In approximately 56% to 75% of patients with obstructive sleep apnea (OSA), the frequency and duration of apneas are influenced by body position. This is referred to as position-dependent OSA or POSA. Patients with POSA can be treated with a small device attached to either the neck or chest. These devices-a new generation of devices for positional therapy (PT)-provide a subtle vibrating stimulus that prevents patients adopting the supine position. The objectives of this study were to determine whether PT is effective in improving sleep study variables and sleepiness, and to assess compliance.

METHODS

A systematic review and meta-analysis.

RESULTS

Three prospective cohort studies and four randomized controlled trials were included in this review. Combined data for studies reporting on the effect of PT show that there was a mean difference of 11.3 events/h (54% reduction) in apnea-hypopnea index and 33.6% (84% reduction) in percentage total sleeping time in the supine position. The standardized mean difference for both parameters demonstrated a large magnitude of effect (> 0.8 in both cases).

CONCLUSIONS

There is strong evidence that the new generation of devices for PT are effective in reducing the apnea-hypopnea index during short-term follow-up. These devices are simple-to-use for patients and clinicians and are reversible. Under study conditions with short-term follow-up, compliance is high; however, long-term compliance cannot be assessed because of lack of reliable data. Additional long-term, high-quality studies are needed to confirm the role of PT as a single or as a combination treatment modality for OSA patients and to assess long-term compliance.

A Sleep Position Trainer for positional sleep apnea: a randomized, controlled trial

We tested the effect of the Sleep Position Trainer, a vibrational device, for positional sleep apnea in an open, randomized controlled trial with 101 patients, where 52 patients were allocated to Sleep Position Trainer and 49 patients to a non-treatment control group for 2 months (Part 1). All patients were then followed as a cohort for a period of 6 months with use of the Sleep Position Trainer (Part 2). The participants were assessed with polygraphy at entry, and after 2 and 6 months. The mean apnea-hypopnea index supine was 35 per h (SD, 18) in the Sleep Position Trainer group and 38 per h (SD, 15) in the control group at entry. In a per protocol analysis, the mean total apnea-hypopnea index at entry and after 2 months in the Sleep Position Trainer group was 18 per h (SD, 10) and 10 per h (SD, 9; P < 0.001) versus 20 per h (SD, 9) and 18 per h (SD, 10; NS) in the control group. The mean supine sleep time decreased from 47% (SD, 22) to 17% (SD, 18; P < 0.001) in the Sleep Position Trainer group after 2 months. In the control group, the mean supine sleep time was 48% (SD, 20) at entry and 39% (SD, 21; NS) after 2 months. The positive effect of Sleep Position Trainer was maintained in all patients treated with Sleep Position Trainer after 6 months. Daytime sleepiness improved after 6 months. Compliance with the Sleep Position Trainer device during the first 2 months, defined as use of Sleep Position Trainer >4 h per night for all weekdays, was 75.5% (SD 21.2). The discontinuation rate was 28.8 and 49.4% after 2 and 6 months, respectively.

A randomized, controlled trial of positional therapy versus oral appliance therapy for position-dependent sleep apnea

OBJECTIVE

To compare the effectiveness of positional therapy (PT) with the sleep position trainer (SPT) to oral appliance therapy (OAT) in patients with mild-to-moderate positional obstructive sleep apnea (POSA).

METHODS

Multicenter, prospective, randomized, controlled trial. Patients with mild-to-moderate POSA (apnea-hypopnea index (AHI) ≥5 ≤ 30/hour sleep) were randomized for PT or OAT. Polysomnography was repeated after 3 months. Efficacy, adherence, mean disease alleviation (MDA), quality of life, dropouts and adverse events were evaluated.

RESULTS

A total of 177 patients were screened for the study; 99 underwent randomization and 81 completed the study. Intention-to-treat (ITT) analysis of median [IQR] AHI showed a reduction in the PT group from 13.0 [9.7-18.5] to 7.0 [3.8-12.8], p < 0.001 and in the OAT group from 11.7 [9.0-16.2] to 9.1 [4.9-11.7], p < 0.001. Mean adherence (≥4 h/night, ≥5 days/week) was 89.3 ± 22.4% for SPT versus 81.3 ± 30.0% in OAT patients, p = 0.208.

CONCLUSIONS

Oral appliance therapy and positional therapy were equally effective in reducing the median AHI in patients with mild-to-moderate POSA. The results of this study have important implications for future OSA treatment guidelines and daily clinical practice. CLINICALTRIALS.

GOV NUMBER

NCT02045576.