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

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.

A review of supine position related obstructive sleep apnea: Classification, epidemiology, pathogenesis and treatment

Supine related obstructive sleep apnea (OSA) is the most common clinical and physiological phenotype of OSA. This condition is recognizable by patients, their families and through polysomnographic recordings. Commonly used definitions distinguish the presence of supine related OSA when respiratory events occur at twice the frequency when the patient lies in the supine compared to non-supine sleeping positions. Recent physiology studies have demonstrated that airway obstruction arises more commonly in the supine position particularly at the level of the soft palate and epiglottis. Increased airway collapsibility is reliability observed supine relative to lateral position. To a lesser extent, changes in control of breathing favour less stable ventilation when the supine sleeping posture is adopted. Many treatments have been developed and trialled to help patients avoid sleeping on their back. The last 10 years has seen the emergence of vibrotactile warning devices that are worn on the patients' neck or chest. High quality randomized controlled trial data is accumulating on the efficacy and common pitfalls of the application of these treatments.

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.

Role of DISE in the surgical outcome for patients with obstructive sleep apnea

PURPOSE

To investigate and compare the surgical outcomes of DISE and non-DISE-guided surgery in cases with obstructive sleep apnea.

METHODS

Sixty-three patients with severe OSA and BMI ≤35 kg/m² were included in the study. Patients were randomly divided into group A where surgical intervention was performed without DISE, and group B where surgery was planned according to the findings of DISE.

RESULTS

In group A, the mean AHI, LO₂, and Snoring index showed a highly significant improvement (P < 0.0001). Group B had highly significant improvements as regards PSG data (P < 0.0001). High significant differences exist when comparing the operative time of both groups (P < 0.0001). On comparing the success rates in both groups, no statistically significant differences were reported (p = 0.6885).

CONCLUSION

Preoperative topo-diagnosis with DISE does not significantly affect the surgical outcomes in OSA. Primary OSA cases could benefit from a no-DISE cost-effective surgical protocol that entails multilevel surgical interventions in a reasonable time.

Suspension-expansion pharyngoplasty: a modified technique for oropharyngeal collapse in obstructive sleep apnea

BACKGROUND AND PURPOSE

Lateral pharyngeal wall (LPW) collapse plays a fundamental role in the pathogenesis of obstructive sleep apnea (OSA) and might determine the severity of the disease. This study presents the suspension/expansion pharyngoplasty (SEP) for the treatment of selected cases of OSA. The procedure aimed to splint LPW collapse via supporting and lateralization of both superior constrictor muscle (SCM) and palatopharyngeal muscle (PPM) individually and in two different planes.

METHODS

Twenty-one adult patients with single-level OSA who showed a lateral pattern of collapse at the oropharyngeal region had the modified procedure (SEP). The basic steps are the individual dissection of the muscular components of the lateral pharyngeal wall: SCM which was sutured anteriorly to the anterior tonsillar pillar and the PPM which was suspended to the pterygomandibular raphe. The supra-tonsillar fat was preserved.

RESULTS

At 9-12 months, highly significant improvement was reported as regards the mean Apnea hypopnea index and the mean lowest oxygen saturation (p < 0.000). The Epworth Sleepiness Scale and VAS-snoring showed a significant (p < 0.05) reduction. The oxygen desaturation index showed significant improvement. Non-significant improvements were reported as regards the percentage of total sleep time with oxygen saturation below 90%. According to Sher criteria, successful outcomes were reported in 17 patients.

CONCLUSION

SEP could widen the pharyngeal airway and could support the collapsible lateral pharyngeal wall guarding against soft tissue collapse. In selected subjects, SEP had reported subjective and objective favorable outcomes with no significant comorbidities. The procedure could be combined with other procedures in multilevel surgery.

LEVEL OF EVIDENCE: 4

Head-Of-Bed Elevation (HOBE) for Improving Positional Obstructive Sleep Apnea (POSA): An Experimental Study

Purpose: Evaluate the effectiveness of the head-of-bed elevation position (HOBE) with a 30° elevation of the head and trunk, in improving obstruction of the upper airways in obstructive sleep apnea (OSA) patients. A prospective trial simultaneously performing drug-induced sleep endoscopy (DISE) and polysomnography (PSG) tests was performed. Methods: Forty-five patients were included in the prospective study protocol. All patients enrolled in the study and underwent the following evaluations: (1) a drug-induced sleep endoscopy, with an evaluation of obstructions and collapse of the upper airways at 0° and in a HOBE position, with head and trunk elevation of 30°; (2) an overnight PSG assessment in the hospital with head and trunk elevation from 0° to 30° during the night; (3) a questionnaire to evaluate the feedback of patients to sleeping with head-of-bed elevation. Results: Velum (V) and oropharynx lateral wall (O) collapses were reduced in the 30° up position. There were no statistical differences that emerged in the obstruction of the tongue base and epiglottis between the 0° position and the 30° up position (p > 0.05). The average AHI score changed from 23.8 ± 13.3 (0° supine position) to 17.7 ± 12.4 (HOBE position), with a statistical difference (p = 0.03); the same statistical difference emerged in the percentage of apneas that decreased from 55 ± 28.1 to 44 ± 25.8 (p = 0.05). Conclusions: By adopting the HOBE position with 30° elevation of the head and trunk, it is possible to obtain a reduction of upper airways collapses and an improvement of apnea/hypopnea events and nightly respiratory outcomes.

Sleep Position Detection with a Wireless Audio-Motion Sensor—A Validation Study

It is well documented that body position significantly affects breathing indices during sleep in patients with obstructive sleep apnea. They usually worsen while changing from a non-supine to a supine position. Therefore, body position should be an accurately measured and credible parameter in all types of sleep studies. The aim of this study was to specify the accuracy of a neck-based monitoring device (Clebre, Olsztyn, Poland) mounted at the suprasternal notch, in determining a supine and non-supine sleeping position, as well as specific body positions during sleep, in comparison to polysomnography (PSG). A sleep study (PSG along with a neck-based audio-motion sensor) was performed on 89 consecutive patients. The accuracy in determining supine and non-supine positions was 96.9%±3.9% and 97.0%±3.6%, respectively. For lateral positions, the accuracy was 98.6%±2% and 97.4%±4.5% for the right and left side, respectively. The prone position was detected with an accuracy of 97.3%±5.6%. The study showed a high accuracy in detecting supine, as well as other gross positions, during sleep based on a sensor attached to the suprasternal notch, compared to the PSG study. We feel that the suprasternal notch is a promising area for placing wireless sleep study devices.

Supine sleep patterns as a part of phenotyping patients with sleep apnea-a pilot study

Purpose

Polysomnography (PSG) is considered the best objective study to diagnose and quantify sleep disorders. However, PSG involves multiple electrodes and is usually performed in a sleep laboratory that in itself may change the physiology of sleep. One of the parameters that can change during PSG is the sleep position, leading to more supine sleep. The aim of this study was to quantify the amount of supine sleep during PSG and compare it to consecutive nights of a home sleep apnea test (HSAT) in the same patients.

Methods

This prospective study evaluated 22 consecutive patients undergoing PSG followed by HSAT. Sleep position was analyzed during PSG and subsequently on 2 to 6 nights (mean 3.7 nights) at home, and the amount of supine sleep was recorded during each night.

Results

Of 22 patients, there were 12 men (55%). The median age was 60.0 years for women and 45.5 years for men. Median proportion of supine sleep during PSG and HSAT was 61% and 26% (p < 0.001), respectively. Four “phenotypes” were identified according to their sleep position during PSG and HSAT, with 5 patients sleeping mainly supine during all nights, 7 patients sleeping mainly non-supine during all nights, 3 patients sleeping in different positions during each night, and 7 patients sleeping supine during PSG but non-supine at home, during HSAT.

Conclusions

There is a higher proportion of supine sleep during PSG compared to home sleep. We identified a subgroup of patients who slept mainly supine during PSG and mainly non-supine during HSAT. PSG may overestimate OSA severity in a specific phenotype of patients.

How reliable is measurement of posture during sleep: real-world measurement of body posture and movement during sleep using accelerometers

Objective Understanding sleeping behaviours could improve prevention and treatment of sleep problems and associated health conditions. This study aimed to evaluate a method to assess body posture and movement during sleep using trunk-worn accelerometers for 28 days. Approach Participants (50 adults with low back pain (66% female); aged 32(±9) years) wore two activPAL-micro sensors (thigh, trunk) during their normal daily life for 28 consecutive days. Parameters related to body posture (e.g., time spent lying supine or prone) and movement (e.g., number of turns) during sleep were calculated for each night. Average values for each parameter were identified for different periods, the Spearman-Brown Prophecy Formula was used to estimate the minimum number of nights required to obtain a reliable estimate of each parameter, and repeatability of measures between different weeks was calculated. Main Results Participants spent 8.1(±0.8) hours asleep and most time (44%) was spent in a supine posture. The minimum number of nights required for reliable estimates varied between sleep parameters, range 4-21 nights. The most stable parameters (i.e., requiring less than seven nights) were "average activity", "no. of turns", "time spent prone", and "posture changes in the first hour". Some measures differed substantially between weeks. Significance Most sleep parameters related to body posture and movement require a week or more of monitoring to provide reliable estimates of behaviour over one month. Notably, one week may not reflect behaviour in another week, and the time varying nature of sleep needs to be considered.

Position-dependent obstructive sleep apnea and its influence on treatment success of mandibular advancement devices

PURPOSE

Depending on the severity of pre-treatment obstructive sleep apnea (OSA) and the criteria used to define treatment success, the efficacy of mandibular advancement devices (MADs) ranges from 30 to 69%. Identifying suitable candidates is the key to increasing the efficacy of a MAD. Positive predictors include a low body mass index, a low apnea-hypopnea index (AHI), and low age. Another consideration is whether or not a patient's OSA is position dependent. To evaluate the effect of such dependency on MAD treatment success, we studied the following: treatment success across the patient's total AHI and in the supine and non-supine sleeping positions; the influence of pre-treatment position dependency on MAD treatment success; and the effect of MAD treatment on post-treatment shifts in position dependency.

METHODS

This is a single-center retrospective study of patients with OSA. Patients were diagnosed through an overnight polysomnography and treated with a MAD between February 2015 and January 2018. They were defined as being positional if the AHI in supine sleeping position was at least twice as high as in the non-supine position.

RESULTS

Complete treatment success was achieved in 32% of study population (n = 96) and partial success in 54%. Complete treatment success was significantly higher (p = 0.004) when a patient was sleeping in the non-supine position. Treatment success did not differ significantly between patients who were position dependent and those who were not. When treated with a MAD, patients did not spend significantly more time in supine position. Neither did we find any post-treatment shifts in position dependency.

CONCLUSION

A MAD is an effective treatment modality that may significantly reduce the total AHI, supine, and non-supine AHI. Since position dependency has no impact on MAD treatment success, it does not determine whether or not a patient is a suitable candidate for MAD treatment.

The predictive value of drug-induced sleep endoscopy for treatment success with a mandibular advancement device or positional therapy for patients with obstructive sleep apnea

PURPOSE

As drug-induced sleep endoscopy (DISE) can provide additional diagnostic information on collapse patterns of the upper-airway, it is widely used in patients with obstructive sleep apnea (OSA). Although more controversial, DISE may also predict the success of treatment with a mandibular advancement device (MAD) and/or positional therapy (PT). In 2018, we proposed a prediction model to investigate the predictive value of passive maneuvers during DISE - such as jaw thrust and changes in body position - on upper-airway patency. Based on the outcomes of various studies, we then adjusted our DISE protocol to better mimic the effect of a MAD, PT, or a combination of both. The aim of this study was to verify whether or not our adjustments would increase the value of DISE as a selection tool.

METHODS

This single-center retrospective cohort study involved a consecutive series of patients with OSA. Patients were included if a DISE had been performed in supine and non-supine sleeping position and with and without a boil-and-bite MAD in situ between December 2018 and February 2020. The VOTE scoring system was used to evaluate the obstruction at four levels of the upper-airway.

RESULTS

Among 94 patients included. the median apnea-hypopnea index (AHI) was 16.2 (events/h). As a temporary MAD during DISE reduced obstruction by 54% and jaw thrust by 57%, both mimicked the effect of the custom-made MADs referred to in the literature, which reduces the AHI by 60%. Head-and-trunk rotation reduced obstruction by 55% and thus mimicked the effect of PT, which is known to reduce the AHI by 50%.

CONCLUSION

A jaw thrust, a temporary MAD, and head-and-trunk rotation during DISE all seem to mimic the treatment effects of MAD and PT. These findings may be of added value when choosing OSA treatment. To prove the predictive value of these maneuvers during DISE, a prospective study should be performed.