Full-body Postural Alignment Analysis Through Barycentremetry

STUDY DESIGN

Multicentric retrospective.

OBJECTIVE

The study of center of mass (COM) locations (i.e. barycentremetry) can help us understand postural alignment. This study goal was to determine relationships between COM locations and global postural alignment X-ray parameters in healthy subjects. The second objective was to determine the impact on spinopelvic alignment of increased distance between anterior body envelope and spine at lumbar apex level.

SUMMARY OF BACKGROUND DATA

Unexplored relationship between COM location and spinopelvic parameters.

METHODS

This study included healthy volunteers with full-body biplanar radiograph including body envelope reconstruction, allowing the estimation of COM location. The following parameters were analyzed: lumbar lordosis (LL), thoracic kyphosis (TK), cervical lordosis (CL), pelvic tilt (PT), Sacro-femoral angle (SFA), Knee flexion angle (KFA), sagittal odontoid-hip axis angle (ODHA). The following COM in the sagittal plane were located: whole body, at thoracolumbar inflexion point, and body segment above TK apex. The body envelope reconstruction also provided the distance between anterior skin and the LL apex vertebral body center ("SV-L distance").

RESULTS

This study included 124 volunteers, with a mean age of 44±19.3. Multivariate analysis confirmed posterior translation of COM above TK apex with increasing LL (P=0.002) through its proximal component, and posterior shift of COM at inflexion point with increasing TK (P=0.008). Increased SV-L distance was associated with greater ODHA (r=0.4) and more anterior body COM (r=0.8), caused by increased TK (r=0.2) and decreased proximal and distal LL (both r=0.3), resulting in an augmentation in SFA (r=0.3) (all P<0.01).

CONCLUSIONS

Barycentremetry showed that greater LL was associated with posterior shift of COM above thoracic apex while greater TK was correlated with more posterior COM at inflexion point. Whole-body COM was strongly correlated with ODHA. This study also exhibited significant alignment disruption associated with increased abdominal volume, with compensatory hip extension.

LEVEL OF EVIDENCE

II.

Long-Term Efficacy and Safety of Pitolisant for Residual Sleepiness Due to OSA

BACKGROUND

In people with OSA, excessive daytime sleepiness is a prominent symptom and can persist despite adherence to CPAP, the first-line therapy for OSA. Pitolisant was effective in reducing daytime sleepiness in two 12-week randomized controlled trials (RCTs), one in patients adherent to CPAP (BF2.649 in Patients With OSA and Treated by CPAP But Still Complaining of EDS [HAROSA 1]) and the other in patients refusing or not tolerating CPAP (BF2.649 in Patients With OSA, Still Complaining of EDS and Refusing to be Treated by CPAP [HAROSA 2]).

RESEARCH QUESTION

Does the efficacy and safety of pitolisant persist when these patients take it long-term?

STUDY DESIGN AND METHODS

All adults included in the HAROSA 1 and HAROSA 2 RCTs (both pitolisant and placebo arms) were offered pitolisant (up to 20 mg/d) after completion of the short-term double-anonymized phase (ie, from week 13) in an open-label cohort study. The primary efficacy outcome was the change in Epworth Sleepiness Scale score between baseline and week 52. Safety outcomes were treatment-emergent adverse event(s) (TEAE[s]), serious TEAEs, and special interest TEAEs.

RESULTS

Out of 512 adults included in the two RCTs, 376 completed the 1-year follow-up. The pooled mean difference in Epworth Sleepiness Scale score from baseline to 1 year for the intention-to-treat sample was -8.0 (95% CI, -8.3 to -7.5). The overall proportions of TEAEs, serious TEAEs, and TEAEs of special interest were 35.1%, 2.0%, and 11.1%, respectively, without any significant difference between patients in the initial pitolisant and placebo arms. No cardiovascular safety issues were reported.

INTERPRETATION

Pitolisant is effective in reducing daytime sleepiness over 1 year in adults with OSA, with or without CPAP treatment. Taken for 1 year, it has a good safety profile (including cardiovascular).

TRIAL REGISTRATION

ClinicalTrials.gov; Nos.: NCT01071876 and NCT01072968; URL: www.

CLINICALTRIALS

gov.

Neurophysiological basis of respiratory discomfort improvement by mandibular advancement in awake OSA patients

Patients with obstructive sleep apneas (OSA) do not complain from dyspnea during resting breathing. Placement of a mandibular advancement device (MAD) can lead to a sense of improved respiratory comfort ("pseudo-relief") ascribed to a habituation phenomenon. To substantiate this conjecture, we hypothesized that, in non-dyspneic awake OSA patients, respiratory-related electroencephalographic figures, abnormally present during awake resting breathing, would disappear or change in parallel with MAD-associated pseudo-relief. In 20 patients, we compared natural breathing and breathing with MAD on: breathing discomfort (transitional visual analog scale, VAS-2); upper airway mechanics, assessed in terms of pressure peak/time to peak (TTP) ratio respiratory-related electroencephalography (EEG) signatures, including slow event-related preinspiratory potentials; and a between-state discrimination based on continuous connectivity evaluation. MAD improved breathing and upper airway mechanics. The 8 patients in whom the EEG between-state discrimination was considered effective exhibited higher Peak/TTP improvement and transitional VAS ratings while wearing MAD than the 12 patients where it was not. These results support the notion of habituation to abnormal respiratory-related afferents in OSA patients and fuel the causative nature of the relationship between dyspnea, respiratory-related motor cortical activity and impaired upper airway mechanics in this setting.

Auto-adjusted versus fixed positive airway pressure in patients with severe OSA: A large randomized controlled trial

BACKGROUND AND OBJECTIVE

Continuous positive airway pressure (CPAP) in the treatment of severe obstructive sleep apnoea (OSA) can be used in fixed CPAP or auto-adjusted (APAP) mode. The aim of this prospective randomized controlled clinical study was to evaluate the 3 month-efficacy of CPAP used either in fixed CPAP or APAP mode.

METHODS

Eight hundred one patients with severe OSA were included in twenty-two French centres. After 7 days during which all patients were treated with APAP to determine the effective pressure level and its variability, 353 and 351 patients were respectively randomized in the fixed CPAP group and APAP group. After 3 months of treatment, 308 patients in each group were analysed.

RESULTS

There was no difference between the two groups in terms of efficacy whatever the level of efficient pressure and pressure variability (p = 0.41). Exactly, 219 of 308 patients (71.1%) in the fixed CPAP group and 212 of 308 (68.8%) in the APAP group (p = 0.49) demonstrated residual apnoea hypopnoea index (AHI) <10/h and Epworth Score <11. Tolerance and adherence were also identical with a similar effect on quality of life and blood pressure evaluation.

CONCLUSION

The two CPAP modes, fixed CPAP and APAP, were equally effective and tolerated in severe OSA patients.

Do the EEG and behavioral criteria of NREM arousal disorders apply to sexsomnia?

STUDY OBJECTIVES

To establish whether the recent EEG and behavioral criteria of arousal disorders apply to sexsomnia.

METHODS

EEG and behavioral markers upon N3 sleep interruptions in videopolysomnography were retrospectively compared in 24 participants with sexsomnia, 41 participants with arousals disorders, and 40 healthy controls. The specificity and sensitivity of previously suggested EEG and behavioral cutoffs for supporting arousal disorders diagnosis were measured in the sexsomnia vs. control groups.

RESULTS

Participants with sexsomnia and arousals disorders showed a higher N3 fragmentation index, slow/mixed N3 arousal index, and number of eye openings during N3 interruptions than healthy controls. Ten (41.7%) participants with sexsomnia (vs. one sleepwalker and no control) displayed an apparently sexual behavior (masturbation, sexual vocalization, pelvic thrusting, and hand within the pajama) during N3 arousal. An N3 sleep fragmentation index ≥ 6.8/h of N3 sleep and two or more N3 arousals associated with eye opening was 95% specific but poorly (46% and 42%) sensitive for diagnosing sexsomnia. An index of slow/mixed N3 arousals ≥ 2.5/h of N3 sleep was 73% specific and 67% sensitive. An N3 arousal with trunk raising, sitting, speaking, showing an expression of fear/surprise, shouting, or exhibiting sexual behavior was 100% specific for a diagnosis of sexsomnia.

CONCLUSION

In patients with sexsomnia, videopolysomnography based markers of arousal disorders are intermediate between healthy individuals and patients with other arousal disorders, supporting the concept of sexsomnia as a specialized, but less neurophysiologically severe, NREM parasomnia. Previously validated criteria for arousal disorders partially fit in patients with sexsomnia.

Moderate-to-severe obstructive sleep apnea syndrome is associated with altered tongue motion during wakefulness

PURPOSE

Impairment of genioglossus control is a frequent "non-anatomical" cause of obstructive sleep apnea syndrome (OSAS) in non- or mildly obese patients. Although wake-related compensatory mechanisms prevent the occurrence of obstructive events, the genioglossus control is often impaired during wakefulness. We hypothesized that the lingual motion would be altered during wakefulness in this population in patients with moderate-to-severe OSAS.

METHODS

We included non- or mildly obese participants with suspected OSAS. They underwent a Bucco-Linguo-Facial Motor Skills assessment using the MBLF ("Motricité Bucco-Linguo-Faciale"), which includes an evaluation of 13 movements of the tongue. This was followed by a night-attended polysomnography. We compared patients with moderate-to-severe OSAS (apnea-hypopnea index (AHI) ≥ 15/h; n = 15) to patients without or with mild OSAS (AHI < 15/h; n = 24).

RESULTS

MBLF total and "tongue" sub-scores were lower in patients with moderate-to-severe OSAS: total z-score - 0.78 [- 1.31; 0.103] versus 0.20 [- 0.26; 0.31], p = 0.0011; "tongue" z-sub-score (- 0.63 [- 1.83; 0.41] versus 0.35 [0.26; 0.48], p = 0.014). There was a significant age-adjusted correlation between the "tongue" sub-score and AHI. The logistic regression model for the prediction of moderate-to-severe OSAS gave area under the curve ratio of 88.2% for MBLF score plus age.

CONCLUSIONS

Myofunctional activity of the tongue is impaired during wakefulness in non- or mildly obese patients with moderate-to-severe OSAS. This study supports the lingual myofunctional assessment using the MBLF in screening of moderate-to-severe OSAS. This simple tool could help clinicians to select patients with suspected moderate-to-severe OSAS for polysomnography.

The rib cage: a new element in the spinopelvic chain

INTRODUCTION

This study analyzes anatomical variations of the thoracic cage (TC) according to spinopelvic alignment, age and gender using stereoradiography in erect position.

METHODS

This retrospective multicentric study analyzed computed parameters collected from free-standing position bi-planar radiographs, among healthy subjects. Collected data were: age, gender, pelvic parameters (Pelvic Incidence, Pelvic Tilt (PT) and Sacral Slope), T1-T12 Kyphosis (TK), L1-S1 Lordosis (LL), curvilinear spinal length, global TC parameters (maximum thickness and width, rib cage volume, mean Spinal Penetration Index (SPI)), 1st-10th rib parameters (absolute and relative (to the corresponding vertebra) sagittal angles).

RESULTS

Totally, 256 subjects were included (140 females). Mean age was 34 (range: 8-83). Significant correlations were found between TK and TC thickness (0.3, p < 0.001) and with TC Volume (0.3, p = 0.04), as well as rib absolute sagittal angle for upper and middle ribs (0.2, p = 0.02). Conversely, a -0.3 correlation has been exhibited between SPI and TK. Similar correlations were found with LL. PT significantly correlated with TC thickness (0.4, p = 0.003), SPI (-0.3, p = 0.03), and all rib relative sagittal angles. Among global TC parameters, only thickness and SPI significantly changed after 20 years (respectively, 0.39 and -0.52, p < 0.001). Ribs relative sagittal angle showed negative correlation with age in skeletally mature subjects (p < 0.001).

CONCLUSION

This study demonstrates the correlation between TC anatomy and spinopelvic parameters, confirming its part of the spinopelvic chain of balance. Indeed, higher spinal curvatures were associated with lower SPI and higher TC thickness, TC volume and rib absolute sagittal angles.

Proposals from a French expert panel for respiratory care in ALS patients

BACKGROUND

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by progressive diaphragm weakness and deteriorating lung function. Bulbar involvement and cough weakness contribute to respiratory morbidity and mortality. ALS-related respiratory failure significantly affects quality of life and is the leading cause of death. Non-invasive ventilation (NIV), which is the main recognized treatment for alleviating the symptoms of respiratory failure, prolongs survival and improves quality of life. However, the optimal timing for the initiation of NIV is still a matter of debate. NIV is a complex intervention. Multiple factors influence the efficacy of NIV and patient adherence. The aim of this work was to develop practical evidence-based advices to standardize the respiratory care of ALS patients in French tertiary care centres.

METHODS

For each proposal, a French expert panel systematically searched an indexed bibliography and prepared a written literature review that was then shared and discussed. A combined draft was prepared by the chairman for further discussion. All of the proposals were unanimously approved by the expert panel.

RESULTS

The French expert panel updated the criteria for initiating NIV in ALS patients. The most recent criteria were established in 2005. Practical advice for NIV initiation were included and the value of each tool available for NIV monitoring was reviewed. A strategy to optimize NIV parameters was suggested. Revisions were also suggested for the use of mechanically assisted cough devices in ALS patients.

CONCLUSION

Our French expert panel proposes an evidence-based review to update the respiratory care recommendations for ALS patients in daily practice.

Biplanar Low-Dose Radiograph Is Suitable for Cephalometric Analysis in Patients Requiring 3D Evaluation of the Whole Skeleton

BACKGROUND

The biplanar 2D/3D X-ray technology (BPXR) is a 2D/3D imaging system allowing simultaneous stereo-corresponding posteroanterior (PA) and lateral 2D views of the whole body. The aim of our study was to assess the feasibility of cephalometric analysis based on the BPXR lateral skull view to accurately characterize facial morphology.

METHOD

A total of 17 landmarks and 11 angles were placed and/or calculated on lateral BPXR and lateral cephalograms of 13 patients by three investigators. Five methods of angle identification were performed: the direct construction of straight lines on lateral cephalograms (LC-A) and on BPXR (BPXR-A), as well as the calculation of angles based on landmark identification on lateral cephalograms (LA-L) and on BPXR with the PA image (BPXR-LPA) or without (BPXR-L). Intra- and interoperator reliability of landmark identification and angle measurement of each method were calculated. To determine the most reliable method among the BPXR-based methods, their concordance with the reference method, LC-A, was evaluated.

RESULTS

Both imaging techniques had excellent intra- and interoperator reliability for landmark identification. On lateral BPXR, BPXR-A presented the best concordance with the reference method and a good intra- and interoperator reliability.

CONCLUSION

BPXR provides a lateral view of the skull suitable for cephalometric analysis with good reliability.

Mandibular advancement device use in obstructive sleep apnea: ORCADES study 5-year follow-up data

STUDY OBJECTIVES

Mandibular advancement devices (MADs) are an alternative to continuous positive airway pressure for the management of obstructive sleep apnea (OSA). The ORthèse d'avanCée mAndibulaire dans le traitement en DEuxième intention du SAHOS sévère (ORCADES) study is investigating the long-term effectiveness of MAD therapy in patients with OSA who refused or were intolerant of continuous positive airway pressure. Five-year follow-up data are presented.

METHODS

Data were available in 172 of 331 patients treated with a custom-made computer-aided design/computer-aided manufacturing biblock MAD (Narval CC; ResMed, Saint-Priest, France). The primary end point was treatment success (≥50% decrease in apnea-hypopnea index from baseline).

RESULTS

Five-year treatment success rates were 52% overall and 25%, 52%, and 63%, respectively, in patients with mild, moderate, or severe OSA. This reflects a decline over time vs 3-6 months (79% overall) and 2 years (68%). Rates declined in all patient subgroups but to the greatest extent in patients with mild OSA. The slight worsening of respiratory parameters over time was not associated with any relevant changes in sleepiness and symptoms. Moderate or severe OSA at baseline, treatment success at 3-6 months, and no previous continuous positive airway pressure use were significant independent predictors of 5-year treatment success on multivariate analysis. No new safety signals emerged during long-term follow-up. The proportion of patients using their MAD for ≥4 h/night on ≥4 days/wk was 93.3%; 91.3% of patients reported device use of ≥6 h/night at 5 years. At 5-year follow-up, 96.5% of patients reported that they wanted to continue MAD therapy.

CONCLUSIONS

Long-term MAD therapy remained effective after 5 years in >50% of patients, with good levels of patient satisfaction and adherence.

CITATION

Vecchierini MF, Attali V, Collet JM, et al. Mandibular advancement device use in obstructive sleep apnea: ORCADES study 5-year follow-up data. J Clin Sleep Med. 2021;17(8):1695-1705.

Interaction between posture and maxillomandibular deformity: a systematic review

Maxillomandibular deformity (MMD) and body posture appear to be correlated. However, no systematic literature review of the available evidence to support this correlation has been performed to date. The aim of this study was to conduct a systematic literature review on posture and MMD. This systematic literature review was registered in the PROSPERO database. Systematic searches of the MEDLINE, Scopus, Cochrane Library, and Web of Science databases were performed. In total, 13 clinical studies were included. Nine found a significant association between MMD and body posture or body balance: two studies showed a correlation between increased cervical lordosis and skeletal class III MMD, two studies showed an interaction between mandibular deviation and scoliosis, four studies demonstrated a significant association between lumbar column and pelvis anatomy and MMD, and one study found a correlation between displacement of the centre of mass and MMD. However, the level of evidence is low; the methods used to evaluate body posture and MMD were inconsistent. Orthognathic surgery could modify body posture. Although there seems to be an interaction between body posture and facial deformity, the number of studies is too small and the level of evidence too low to strongly support this association.

Pitolisant for Residual Excessive Daytime Sleepiness in OSA Patients Adhering to CPAP: A Randomized Trial

BACKGROUND

Excessive daytime sleepiness (EDS) in individuals with OSA syndrome persisting despite good adherence to CPAP is a disabling condition. Pitolisant is a selective histamine H3-receptor antagonist with wake-promoting effects.

RESEARCH QUESTION

Is pitolisant effective and safe for reducing daytime sleepiness in individuals with moderate to severe OSA adhering to CPAP treatment but experiencing residual EDS?

STUDY DESIGN AND METHODS

In a multicenter, double-blind, randomized (3:1), placebo-controlled, parallel-design trial, pitolisant was titrated individually at up to 20 mg/day and taken over 12 weeks. The primary end point was change in the Epworth Sleepiness Scale (ESS) score in the intention-to-treat population. Key secondary end points were maintenance of wakefulness assessed by the Oxford Sleep Resistance Test, Clinical Global Impressions scale of severity, the patient's global opinion, EuroQoL quality-of-life questionnaire score, Pichot fatigue questionnaire score, and safety.

RESULTS

Two hundred forty-four OSA participants (82.8% men; mean age, 53.1 years; mean Apnea Hypopnea Index with CPAP, 4.2/h; baseline ESS score, 14.7) were randomized to pitolisant (n = 183) or placebo (n = 61). ESS significantly decreased with pitolisant compared with placebo (-2.6; 95% CI, -3.9 to -1.4; P < .001), and the rate of responders to therapy (ESS ≤ 10 or change in ESS ≥ 3) was significantly higher with pitolisant (71.0% vs 54.1%; P = .013). Adverse event occurrence (mainly headache and insomnia) was higher in the pitolisant group compared with the placebo group (47.0% and 32.8%, respectively; P = .03). No cardiovascular or other significant safety concerns were reported.

INTERPRETATION

Pitolisant used as adjunct to CPAP therapy for OSA with residual sleepiness despite good CPAP adherence significantly reduced subjective and objective sleepiness and improved participant-reported outcomes and physician-reported disease severity.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT01071876; URL: www.clinicaltrials.gov; EudraCT N°: 2009-017248-14; URL: eudract.ema.europa.eu.

Baclofen destabilises breathing during sleep in healthy humans: A randomised, controlled, double-blind crossover trial

AIMS

Periodic breathing is frequent in patients with severe heart failure. Apart from being an indicator of severity, periodic breathing has its own deleterious consequences (sleep-related oxygen desaturations, sleep fragmentation), which justifies attempts to correct it irrespective of the underlying disease. Animal models and human data suggest that baclofen can reconfigure respiratory central pattern generators. We hypothesised that baclofen, a GABA_B agonist, may thus be able to correct periodic breathing in humans.

METHODS

Healthy volunteers were exposed to hypoxia during sleep. Participants who developed periodic breathing (n = 14 [53 screened]) were randomly assigned to double-blind oral baclofen (progressively increased to 60 mg/d) or placebo. The primary outcome was the coefficient of variation (CoVar) of respiratory cycle total time considered as an indicator of breathing irregularity. Secondary outcomes included the CoVar of tidal volume, apnoea-hypopnoea index, sleep fragmentation index and ventilatory complexity (noise limit).

RESULTS

The analysis was conducted in 9 subjects after exclusion of incomplete datasets. CoVar of respiratory cycle total time significantly increased with baclofen during non-rapid eye movement sleep (median with placebo 56.00% [37.63-78.95]; baclofen 85.42% [68.37-86.40], P = .020; significant difference during the N1-N2 phases of sleep but not during the N3 phase). CoVar of tidal volume significantly increased during N1-N2 sleep. The apnoea-hypopnoea index, sleep fragmentation index and ventilatory complexity were not significantly different between placebo and baclofen.

CONCLUSION

Baclofen did not stabilise breathing in our model. On the contrary, it increased respiratory variability. Baclofen should probably not be used in patients with or at risk of periodic breathing.

0665 Bilateral Hypoglossal Nerve Stimulation for Treatment of Obstructive Sleep Apnea

Introduction

Hypoglossal Nerve Stimulation (HGNS) decreases obstructive sleep apnea (OSA) severity by contracting the tongue and decreasing upper airway collapsibility. This study assessed the safety and effectiveness of a new implantable device that delivers bilateral HGNS: the Genio™ system.

Methods

The BLAST OSA study (BiLAteral Hypoglossal Nerve Stimulation for Treatment of Obstructive Sleep Apnea), was a prospective, open-label, non-randomized, single arm treatment study conducted at eight centres in three countries (Australia, France, UK). Primary outcomes were the incidence of device-related Serious Adverse Events (SAEs) and change in the Apnea-Hypopnea Index (AHI). The secondary outcome was change in the 4% Oxygen Desaturation Index (ODI). Additional outcomes included measures of sleepiness, quality of life, snoring, and device use. Participants were eligible if: 21-75 years old; BMI ≤ 32 kg/m2; obstructive AHI 20-60 events/hr and combined central and mixed AHI &lt; 10 events/hr; no positional OSA; no Complete Concentric Collapse of the soft palate during Drug Induced Sleep Endoscopy; and failed to tolerate or accept Positive Airway Pressure treatments.

Results

27 participants were implanted (63% male, aged 55.9±12.0 years, BMI 27.4±3.0 kg/m2). 22 completed the protocol. At 6 months, AHI decreased from 23.7±12.2 to 12.9±10.1 events/hr [p&lt;0.001]; and ODI decreased from 19.1±11.2 to 9.8±6.9 events/hr [p&lt;0.001]. Daytime sleepiness (ESS, p=0.011) and sleep-related quality of life (FOSQ-10, p=0.016) both significantly improved. 91% of participants reported using their device &gt;5 days per week, and 77% used it &gt;5 hours per night. The number of bed partners reporting disruptive snoring decreased from 96% to 35%. No device-related SAE occurred.

Conclusion

In a targeted population of individuals with moderate-to-severe OSA, the Genio system reduced OSA severity and sleepiness, improved quality of life, and was associated with high adherence and an acceptable safety profile.

Support

This study trial was funded by Nyxoah S.A. This trial was registered with ClinicalTrials.gov, number NCT03048604.

Decreased respiratory-related postural perturbations at the cervical level under cognitive load

PURPOSE

In healthy humans, postural and respiratory dynamics are intimately linked and a breathing-related postural perturbation is evident in joint kinematics. A cognitive dual-task paradigm that is known to induce both postural and ventilatory disturbances can be used to modulate this multijoint posturo-ventilatory (PV) interaction, particularly in the cervical spine, which supports the head. The objective of this study was to assess this modulation.

METHODS

With the use of optoelectronic sensors, the breathing profile, articular joint motions of the cervical spine, hip, knees and ankles, and centre of pressure (CoP) displacement were measured in 20 healthy subjects (37 years old [29; 49], 10 females) during natural breathing (NB), a cognitive dual task (COG), and eyes-closed and increased-tidal-volume conditions. The PV interaction in the CoP and joint motions were evaluated by calculating the respiratory emergence (REm).

RESULTS

Only the COG condition induced a decrease in the cervical REm (NB: 17.2% [7.8; 37.2]; COG: 4.2% [1.8; 10.0] p = 0.0020) concurrent with no changes in the cervical motion. The CoP REm (NB: 6.2% [3.8; 10.3]; COG: 12.9% [5.8; 20.7] p = 0.0696) and breathing frequency (NB: 16.6 min-1 [13.3; 18.7]; COG: 18.6 min-1 [16.3; 19.4] p = 0.0731) tended to increase, while the CoP (p = 0.0072) and lower joint motion displacements (p < 0.05) increased.

CONCLUSION

This study shows stable cervical spine motion during a cognitive dual task, as well as increased postural perturbations globally and in other joints. The concurrent reduction in the PV interaction at the cervical spine suggests that this "stabilization strategy" is centrally controlled and is achieved by a reduction in the breathing-related postural perturbations at this level. Whether this strategy is a goal for maintaining balance remains to be studied.

Cervical Spine Hyperextension and Altered Posturo-Respiratory Coupling in Patients With Obstructive Sleep Apnea Syndrome

Obstructive sleep apnea syndrome (OSAS) is associated with postural dysfunction characterized by abnormal spinal curvature and disturbance of balance and walking, whose pathophysiology is poorly understood. We hypothesized that it may be the result of a pathological interaction between postural and ventilatory functions. Twelve patients with OSAS (4 women, age 53 years [51–63] (median [quartiles]), apnea hypopnea index 31/h [24–41]) were compared with 12 healthy matched controls. Low dose biplanar X-rays (EOS® system) were acquired and personalized three-dimensional models of the spine and pelvis were reconstructed. We also estimated posturo-respiratory coupling by measurement of respiratory emergence, obtaining synchronized center of pressure data from a stabilometric platform and ventilation data recorded by an optico-electronic system of movement analysis. Compared with controls, OSAS patients, had cervical hyperextension with anterior projection of the head (angle OD-C7 12° [8; 14] vs. 5° [4; 8]; p = 0.002), and thoracic hyperkyphosis (angle T1–T12 65° [51; 71] vs. 49° [42; 59]; p = 0.039). Along the mediolateral axis: (1) center of pressure displacement was greater in OSAS patients, whose balance was poorer (19.2 mm [14.2; 31.5] vs. 8.5 [1.4; 17.8]; p = 0.008); (2) respiratory emergence was greater in OSAS patients, who showed increased postural disturbance of respiratory origin (19.2% [9.9; 24.0] vs. 8.1% [6.4; 10.4]; p = 0.028). These results are evidence for the centrally-mediated and primarily respiratory origin of the postural dysfunction in OSAS. It is characterized by an hyperextension of the cervical spine with a compensatory hyperkyphosis, and an alteration in posturo-respiratory coupling, apparently secondary to upper airway instability.

Bilateral hypoglossal nerve stimulation for treatment of adult obstructive sleep apnoea

BACKGROUND AND AIM

Hypoglossal nerve stimulation (HNS) decreases obstructive sleep apnoea (OSA) severity via genioglossus muscle activation and decreased upper airway collapsibility. This study assessed the safety and effectiveness at 6 months post-implantation of a novel device delivering bilateral HNS via a small implanted electrode activated by a unit worn externally, to treat OSA: the Genio™ system.

METHODS

This prospective, open-label, non-randomised, single-arm treatment study was conducted at eight centres in three countries (Australia, France and the UK). Primary outcomes were incidence of device-related serious adverse events and change in the apnoea-hypopnoea index (AHI). The secondary outcome was the change in the 4% oxygen desaturation index (ODI). Additional outcomes included measures of sleepiness, quality of life, snoring and device use. This trial was registered with ClinicalTrials.gov, number NCT03048604.

RESULTS

22 out of 27 implanted participants (63% male, aged 55.9±12.0 years, body mass index (BMI) 27.4±3.0 kg·m^-2) completed the protocol. At 6 months BMI was unchanged (p=0.85); AHI decreased from 23.7±12.2 to 12.9±10.1 events·h^-1, a mean change of 10.8 events·h^-1 (p<0.001); and ODI decreased from 19.1±11.2 to 9.8±6.9 events·h^-1, a mean change of 9.3 events·h^-1 (p<0.001). Daytime sleepiness (Epworth Sleepiness Scale; p=0.01) and sleep-related quality of life (Functional Outcomes of Sleep Questionnaire-10; p=0.02) both improved significantly. The number of bed partners reporting loud, very intense snoring, or leaving the bedroom due to participant snoring decreased from 96% to 35%. 91% of participants reported device use >5 days per week, and 77% reported use for >5 h per night. No device-related serious adverse events occurred during the 6-month post-implantation period.

CONCLUSIONS

Bilateral HNS using the Genio™ system reduces OSA severity and improves quality of life without device-related complications. The results are comparable with previously published HNS systems despite minimal implanted components and a simple stimulation algorithm.

Efficacy and tolerability of a custom-made Narval mandibular repositioning device for the treatment of obstructive sleep apnea: ORCADES study 2-year follow-up data

OBJECTIVE/BACKGROUND

Mandibular repositioning device (MRD) therapy is an alternative to continuous positive airway pressure (CPAP). The Orkney Complex Disease Study-ORCADES study is assessing the long-term efficacy and tolerability of MRD therapy in obstructive sleep apnoea syndrome (OSAS); two-year follow-up data are presented.

PATIENTS/METHODS

OSAS patients who refused or were noncompliant with CPAP were fitted with a custom-made computer-aided design/computer-aided manufacturing (CAD/CAM) bi-block MRD (ResMed, Narval CC™); mandibular advancement was individually titrated. Sleep and respiratory parameters were determined at baseline, 3-6 months, and two years. The primary endpoint was treatment success (percentage of patients achieving a ≥50% reduction in the apnoea-hypopnoea index [AHI]).

RESULTS

Of 315 enrolled patients, 237 remained on MRD treatment at two years, and 197 had follow-up data. The treatment success rate at two years was 67%; AHI <5/h, <10/h and <15/h was achieved in 30%, 56% and 72% of patients, respectively. On multivariate analysis, ≥50% decrease in AHI at 3-6 months and absence of nocturia at 3-6 months were significant predictors of MRD treatment continuation. Adverse events were generally mild, and the majority occurred in the first year of treatment.

CONCLUSIONS

Two years' treatment with an MRD was effective and well tolerated in patients with mild to severe OSAS who refused or were intolerant of CPAP.

Compensation of Respiratory-Related Postural Perturbation Is Achieved by Maintenance of Head-to-Pelvis Alignment in Healthy Humans

The maintenance of upright balance in healthy humans requires the preservation of a horizontal gaze, best achieved through dynamical adjustments of spinal curvatures and a pelvic tilt that keeps the head-to-pelvis alignment close to vertical. It is currently unknown whether the spinal and pelvic compensations of respiratory-related postural perturbations are associated with preservation of the head-to-pelvis vertical alignment. We tested this hypothesis by comparing postural alignment variables at extreme lung volume (total lung capacity, TLC; residual volume, RV) with their reference value at functional residual capacity (FRC). Forty-eight healthy subjects [22 women; median age of 34 (26; 48) years] were studied using low dose biplanar X-rays (BPXR; EOS^®system). Personalized three-dimensional models of the spine and pelvis were reconstructed at the three lung volumes. Extreme lung volumes were associated with changes of thoracic curvature bringing it outside the normal range. Maximal inspiration reduced thoracic kyphosis [T1–T12 angle = 47° (37; 56), -4° variation (-9; 1), p = 0.0007] while maximal expiration induced hyperkyphosis [T1–T12 angle = 63° (55; 68); +10° variation (5; 12), p = 9 × 10^-12]. Statistically significant (all p < 0.01) cervical and pelvic compensatory changes occurred [C3–C7 angle: +4° (-2; 11) and pelvic tilt +1° (0; 3) during maximal inspiration; C3–C7 angle: -7° (-18; -1) and pelvic tilt +5° (1; 8) during maximal expiration], resulting in preserved head-to-pelvis alignment (no change in the angle between the vertical plane and the line connecting the odontoid process and the midpoint of the line connecting the center of the two femoral heads ODHA). Lung volume related postural perturbations were more marked as a function of age, but age did not affect the head-to-pelvis alignment. These findings should help understand balance alterations in patients with chronic respiratory diseases that modify lung volume and rib cage geometry.

Mandibular advancement reveals long-term suppression of breathing discomfort in patients with obstructive sleep apnea syndrome

Obstructive sleep apnoea syndrome (OSAS) patients do not report breathing discomfort in spite of abnormal upper airway mechanics. We studied respiratory sensations in OSAS patients without and with mandibular advancement device (MAD). Fifty-seven moderate to severe non obese OSAS patients were asked about breathing discomfort using visual analogue scales (VAS) in the sitting position (VAS-1), after lying down (VAS-2), then with MAD (VAS-3). Awake critical closing pressure (awake Pcrit) was measured in 15 patients without then with MAD. None of the patients reported breathing discomfort when sitting but 19 patients (33%) did when lying (VAS-2: -20% or less). A feeling of "easier breathing" with MAD was observed and was more marked in patients reporting breathing discomfort when supine (VAS-3: +66.0% [49.0; 89.0]) than in those not doing so (VAS-3: +28.5% [1.0; 56.5], p = 0.007). MAD-induced change in awake Pcrit was correlated to VAS-3. In conclusion, MAD revealed "latent dyspnea" related to the severity of upper airways mechanics abnormalities in OSAS patients.

Prevalence and Phenotype of Sleep Disorders in 60 Adults With Prader-Willi Syndrome

Study Objectives

Excessive sleepiness is a common symptom in Prader-Willi syndrome (PWS), and it negatively impacts the quality of life. Obstructive sleep apnea and narcolepsy phenotypes have been reported in PWS. We characterized sleep disorders in a large cohort of adults with PWS.

Methods

All consecutive patients with genetically confirmed PWS unselected for sleep-related symptoms, underwent a clinical interview, polysomnography, and multiple sleep latency tests (MSLT, n = 60), followed by long-term (24 hours) polysomnography (n = 22/60).

Results

Among 60 adults evaluated (57% female, aged 25 ± 10 years, body mass index: 39 ± 12 kg/m2), 67% reported excessive sleepiness. According to the sleep study results, 43% had a previously unrecognized hypersomnia disorder, 15% had an isolated sleep breathing disorder, 12% had combined hypersomnia disorder and untreated breathing sleep disorder, and only 30% had normal sleep. Isolated hypersomnia disorder included narcolepsy in 35% (type 1, n = 1, and type 2, n = 8), hypersomnia in 12% (total sleep time >11 hours, n = 2, and MSLT <8 minutes, n = 1), and borderline phenotype in 53% (≥2 sleep onset in REM periods and MSLT >8 minutes, n = 10, and 8 minutes < MSLT < 10 minutes, n = 4). Sleep breathing disorders, isolated and combined, included obstructive sleep apnea (n = 14, already treated in seven), sleep hypoxemia (n = 1) and previously undiagnosed hypoventilation (n = 5). Modafinil was taken by 16 patients (well tolerated in 10), resulting in improved sleepiness over a mean 5-year follow-up period.

Conclusion

Sleepiness affects more than half of adult patients with PWS, with a variety of hypersomnia disorder (narcolepsy, hypersomnia, and borderline phenotypes) and breathing sleep disorders. Earlier diagnosis and management of sleep disorders may improve sleepiness, cognition, and behavior in these patients.

Long-term effectiveness and side effects of mandibular advancement devices on dental and skeletal parameters

INTRODUCTION

Continuous positive airways pressure, generally used to treat obstructive sleep apnea-hypopnea syndrome (OSAHS), is not tolerated well by many patients. An alternative is to treat OSAHS with mandibular advancement devices (MAD). This research assesses the long term (> 2 years) effectiveness and the side effects on dental and skeletal parameters of these devices.

MATERIAL AND METHODS

We selected 24 patients with moderate to severe OSAHS. All were treated with MADs for at least 2 years. We gathered cephalometric teleradiographs in centric relation and sleep recordings before and after the patients were treated. We evaluated the patients' apnea-hypopnea indexes (AHI) as well as their Epworth sleepiness scale (ESS) scores. We measured the inclination of the central incisors and the positions of the upper and lower jaws.

RESULTS

Mandibular advancement devices were used for more than 2 years (3.9 ± 1.9 years). We observed a statistically significant decrease of the patients' AHI and their ESS scores. We also observed a modification of the inclination of the lower central incisors (+0.521; P = 0.047) and of the position of the maxilla (-0.287; P = 0.039).

DISCUSSION

We demonstrated the clinical effectiveness of mandibular advancement devices for treating OSAHS, with a very low rate of side effects on dental and skeletal positions.

Upper airway stabilization by osteopathic manipulation of the sphenopalatine ganglion versus sham manipulation in OSAS patients: a proof-of-concept, randomized, crossover, double-blind, controlled study

Background

Osteopathic manipulative treatment (OMT) of the sphenopalatine ganglion (SPG) is used empirically for the treatment of rhinitis and snoring and is thought to increase pharyngeal stability. This trial was designed to study the effects of this treatment on pharyngeal stability evaluated by critical closing pressure in obstructive sleep apnoea syndrome.

Methods

This single-centre, randomized, crossover, double-blind study compared active manipulation and sham manipulation of the SPG. Randomization was computer-generated. Patients each received one active manipulation and one sham manipulation at an interval of 21 days and were evaluated 30 min and 48 h after each session administered by a qualified osteopath. Neither the patients, nor the investigator performing the evaluations were informed about the order of the two techniques (double-blind). The primary endpoint was the percentage of responding patients presenting increased pharyngeal stability defined by a variation of critical closing pressure (Pcrit) of at least −4 cmH₂O at 30 min. Secondary endpoints were the variation of Pcrit in absolute values, sleepiness and snoring. Others endpoints were lacrimation (Schirmer’s test), induced pain, sensations experienced during OMT.

Results

Ten patients were included and nine (57 [50; 58] years, comprising 7 men, with an apnoea-hypopnoea index of 31.0 [25.5; 33.2]/h; (values are median [quartiles])) were analysed. Seven patients were analysed for the primary endpoint and nine patients were analysed for secondary endpoints. Five patients responded after active manipulation versus no patients after sham manipulation (p = 0.0209). Active manipulation induced more intense pain (p = 0.0089), increased lacrimation (ns) and more tactile, nociceptive and gustatory sensations (13 versus 1) compared to sham manipulation. No significant difference was observed for the other endpoints.

Conclusions

Osteopathic manipulative treatment of the SPG may improve pharyngeal stability in obstructive sleep apnoea syndrome. This trial validates the feasibility of the randomized, controlled, double-blind methodology for evaluation of this osteopathic treatment. Studies on a larger sample size must specify the efficacy on the apnoea-hypopnoea index.

Trial registration

The study was retrospectively registered in the clinicaltrial.gov registry under reference NCT01193738 on 1st September 2010 (first inclusion May 19, 2010).

Electronic supplementary material

The online version of this article (doi: 10.1186/s12906-017-2053-0) contains supplementary material, which is available to authorized users.

Normal sleep on mechanical ventilation in adult patients with congenital central alveolar hypoventilation (Ondine's curse syndrome)

Background

The purpose of this study was to describe the sleep structure (especially slow wave sleep) in adults with congenital central hypoventilation syndrome (CCHS), a rare genetic disease due to mutations in the PHOX2B gene. Fourteen patients aged 23 (19.0; 24.8) years old (median [1^rst-3rd quartiles]) with CCHS underwent a sleep interview and night-time attended polysomnography with their ventilatory support. Their sleep variables were compared to those collected in 15 healthy control subjects matched for age, sex and body mass index.

Results

The latency to N3 sleep was shorter in patients (26.3 min [24.0; 30.1]) than in controls (49.5 min [34.3; 66.9]; P = 0.005), and sleep onset latency tended to be shorter in patients (14.0 min [7.0; 20.5]) than in controls (33.0 min [18.0; 49.0]; P = 0.052). Total sleep time, sleep stage percentages, sleep fragmentation as well as respiratory and movement index were within normal ranges and not different between groups.

Conclusions

Normal sleep in adult patients with CCHS and adequate ventilator support indicates that the PHOX2 gene mutations do not affect brain sleep networks. Consequently, any complaint of disrupted sleep should prompt clinicians to look for the usual causes of sleep disorders, primarily inadequate mechanical ventilation. Shorter N3 latency may indicate a higher need for slow wave sleep, to compensate for the abnormal respiratory-related cortical activity during awake quiet breathing observed in patients with CCH.

Early diaphragm pacing in patients with amyotrophic lateral sclerosis (RespiStimALS): a randomised controlled triple-blind trial

BACKGROUND

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder associated with respiratory muscle weakness and respiratory failure. Non-invasive ventilation alleviates respiratory symptoms and prolongs life, but is a palliative intervention. Slowing the deterioration of diaphragm function before respiratory failure would be desirable. We aimed to assess whether early diaphragm pacing could slow down diaphragm deterioration and would therefore delay the need for non-invasive ventilation.

METHODS

We did a multicentre, randomised, controlled, triple-blind trial in patients with probable or definite ALS in 12 ALS centres in France. The main inclusion criterion was moderate respiratory involvement (forced vital capacity 60-80% predicted). Other key eligibility criteria were age older than 18 years and bilateral responses of the diaphragm to diagnostic phrenic stimulation. All patients were operated laparoscopically and received phrenic stimulators. Clinicians randomly assigned patients (1:1) to receive either active or sham stimulation with a central web-based randomisation system (computer-generated list). Investigators, patients, and an external outcome allocation committee were masked to treatment. The primary outcome was non-invasive ventilation-free survival, analysed in the intention-to-treat population. Safety outcomes were also assessed in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, number NCT01583088.

FINDINGS

Between Sept 27, 2012, and July 8, 2015, 74 participants were randomly assigned to receive either active (n=37) or sham (n=37) stimulation. On July 16, 2015, an unplanned masked analysis was done after another trial showed excess mortality with diaphragm pacing in patients with hypoventilation (DiPALS, ISRCTN 53817913). In view of this finding, we analysed mortality in our study and found excess mortality (death from any cause) in our active stimulation group. We therefore terminated the study on July, 16, 2015. Median non-invasive ventilation-free survival was 6·0 months (95% CI 3·6-8·7) in the active stimulation group versus 8·8 months (4·2-not reached) in the control (sham stimulation) group (hazard ratio 1·96 [95% CI 1·08-3·56], p=0·02). Serious adverse events (mainly capnothorax or pneumothorax, acute respiratory failure, venous thromboembolism, and gastrostomy) were frequent (24 [65%] patients in the active stimulation group vs 22 [59%] patients in the control group). No treatment-related death was reported.

INTERPRETATION

Early diaphragm pacing in patients with ALS and incipient respiratory involvement did not delay non-invasive ventilation and was associated with decreased survival. Diaphragm pacing is not indicated at the early stage of the ALS-related respiratory involvement.

FUNDING

Hospital Program for Clinical Research, French Ministry of Health; French Patients' Association for ALS Research (Association pour la Recherche sur la Sclérose Latérale Amyotrophique); and Thierry de Latran Foundation.

Reduced survival in patients with ALS with upper airway obstructive events on non-invasive ventilation

INTRODUCTION

Non-invasive ventilation (NIV) is part of standard care in amyotrophic lateral sclerosis (ALS). Intolerance or unavailability of NIV, as well as the quality of correction of nocturnal hypoventilation, has a direct impact on prognosis.

OBJECTIVES

We describe the importance of NIV failure due to upper airway obstructive events, the clinical characteristics, as well as their impact on the prognosis of ALS.

METHODS

Retrospective analysis of the data of 190 patients with ALS and NIV in a single centre for the period 2011-2014. 179 patients tolerating NIV for more than 4 h per night without leaks were analysed.

RESULTS

Among the 179 patients, after correction of leaks, 73 remained inadequately ventilated at night (defined as more than 5% of the night spent at <90% of SpO2), as a result of obstructive events in 67% of cases (n=48). Patients who remained inadequately ventilated after optimal adjustment of ventilator settings presented with shorter survival than adequately ventilated patients. Unexpectedly, patients with upper airway obstructive events without nocturnal desaturation and in whom no adjustment of treatment was therefore performed also presented with shorter survival. On initiation of NIV, no difference was demonstrated between patients with and without upper airway obstructive events. In all patients, upper airway obstruction was concomitant with reduction of ventilatory drive.

CONCLUSIONS

This study shows that upper airway obstruction during NIV occurs in patients with ALS and is associated with poorer prognosis. Such events should be identified as they can be corrected by adjusting ventilator settings.

Cortical Drive to Breathe during Wakefulness in Patients with Obstructive Sleep Apnea Syndrome

STUDY OBJECTIVES

The obstructive sleep apnea syndrome (OSAS) involves recurrent sleep-related upper airways (UA) collapse. UA mechanical properties and neural control are altered, imposing a mechanical load on inspiration. UA collapse does not occur during wakefulness, hence arousal-dependent compensation. Experimental inspiratory loading in normal subjects elicits respiratory-related cortical activity. The objective of this study was to test whether awake OSAS patients would exhibit a similar cortical activity.

DESIGN

Descriptive physiology study.

SETTING

Sleep laboratory in a large university affiliated tertiary hospital.

PATIENTS

26 patients with moderate OSAS according to polysomnography (5 < apnea-hypopnea index [AHI] ≤ 30, n = 14) or severe OSAS (AHI > 30, n = 12); 13 non-OSAS patients for comparison.

INTERVENTIONS

None.

MEASUREMENTS

Respiratory time-locked electroencephalographic segments ensemble averaged and analyzed for slow premotor potentials preceding inspiration ("pre-inspiratory potentials" [PIPs]).

RESULTS

PIPs were present in 1/13 controls and 11/26 patients (P = 0.0336; 4/14 "moderate" and 7/12 "severe" patients). Awake OSAS patients therefore exhibit respiratory-related cortical activity during quiet breathing significantly more frequently than non-OSAS individuals. The corresponding PIPs resemble those observed during prepared voluntary inspirations and in response to experimental inspiratory loads in normal subjects, which involve a cortical network comprising the supplementary motor area.

CONCLUSIONS

A respiratory-related cortical activity could contribute to the increased neural drive to upper airway and to inspiratory muscles that has previously been described in obstructive sleep apnea, and could therefore contribute to the arousal-dependent compensation of upper airway abnormalities. Whether or not such cortical compensatory mechanisms have cognitive consequences remains to be determined.

Very early screening for sleep-disordered breathing in acute coronary syndrome in patients without acute heart failure

BACKGROUND

Obstructive sleep apnea (OSA) is frequently associated with acute coronary syndrome (ACS). Screening of sleep-disordered breathing (SDB) has not been previously evaluated in ACS within 72 h in intensive care settings and its management could potentially enhance patients' prognosis. This pilot study assessed the feasibility of SDB screening at the early phase of ACS.

METHODS

All consecutive patients admitted to the coronary care unit (CCU) for ACS without acute heart failure underwent one overnight-attended polysomnography (PSG) within 72 h after admission. A telemonitoring (TM) system was set up to remotely monitor the signals and repair faulty sensors. The 27 recordings were analyzed as respiratory polygraphy (RP) and as PSG, and the results were compared.

RESULTS

The TM system allowed successful intervention in 48% of recordings, resulting in excellent quality PSG for 89% of cases. The prevalence of SDB [apnea-hypopnea index (AHI) ≥ 15/h] was 82% and mainly consisted of central SDB and periodic breathing, except three patients with OSA. Compared with PSG, RP underestimated AHI, probably due to the poor sleep efficiency, reduction of slow-wave sleep, and alteration of rapid eye movement sleep.

CONCLUSION

An early SDB screening by remote-attended PSG is feasible in ACS patients shortly after admission to CCU. The TM enhanced the quality of PSG. A high prevalence of central SDB was noticed, for which the etiology remains unknown. Further large-scale studies are needed to determine whether central SDB is an incidental finding in early ACS and whether the presence and severity of SDB have a prognostic impact.