Assessment of obstructive sleep apnoea in children: What are the challenges we face?

There is an increasing demand for the assessment of sleep-disordered breathing in children of all ages to prevent the deleterious neurocognitive and behaviour consequences of the under-diagnosis and under-treatment of obstructive sleep apnoea [OSA]. OSA can be considered in three broad categories based on predominating contributory features: OSA type 1 [enlarged tonsils and adenoids], type II [Obesity] and type III [craniofacial abnormalities, syndromal, storage diseases and neuromuscular conditions]. The reality is that sleep questionnaires or calculations of body mass index in isolation are poorly predictive of OSA in individuals. Globally, the access to testing in tertiary referral centres is comprehensively overwhelmed by the demand and financial cost. This has prompted the need for better awareness and focussed history taking, matched with simpler tools with acceptable accuracy used in the setting of likely OSA. Consequently, we present key indications for polysomnography and present scalable, existing alternatives for assessment of OSA in the hospital or home setting, using polygraphy, oximetry or contactless sleep monitoring.

Sleep-disordered breathing and lung function abnormalities in adults with congenital heart disease

PURPOSE

Advances in treatment enables most patients with congenital heart diseases (CHD) to survive into adulthood, implying the need to address comorbid conditions in this growing cohort of patients. The aim of this study was to evaluate the prevalence of sleep-disordered breathing (SDB) and lung function abnormalities in patients with adult congenital heart disease (ACHD).

METHODS

Patients with ACHD underwent level 3 sleep testing (Embletta MPR polygraphy) and pulmonary function testing. Results were stratified by the underlying haemodynamic ACHD lesion group.

RESULTS

Patients with ACHD (n = 100) were middle-aged (42.3 ± 14.6 years), 54% male and slightly overweight (BMI 25.9 ± 5.5 kg/m2). Polygraphy revealed a prevalence of sleep apnoea of 39% with 15% of patients presenting with predominantly obstructive apnoeic episodes, while 23% of patients presenting primarily with central sleep apnoea. The distribution of mild, moderate, and severe sleep apnoea in the total study population was 26%, 7% and 6%, respectively. Comparison of apnoea-hypopnoea index, presence of sleep apnoea, and apnoea severity did not offer significant differences between the four ACHD lesion groups (p = 0.29, p = 0.41 and p = 0.18, respectively). Pulmonary function testing revealed obstructive lung disease in 19 of 100 patients. Concomitant chronic obstructive pulmonary disease and obstructive sleep apnoea were diagnosed in 3% of patients and were associated with profound nocturnal desaturation.

CONCLUSION

The findings suggest a mild propensity amongst patients with ACHD to develop SDB that seems to be unaffected by the specific underlying congenital lesion.

Peripheral arterial tonometry versus polysomnography in suspected obstructive sleep apnoea

BACKGROUND

Polysomnography (PSG) is the gold standard for the diagnosis of obstructive sleep apnoea (OSA). Home sleep apnoea testing with peripheral arterial tonometry (PAT) is a recommended diagnostic alternative for patients with an increased risk for OSA. In a large clinical cohort, we investigated concordance and predictors for discordance in diagnosing OSA using PAT and PSG, and three-year cardiovascular risk in patients with discordant OSA diagnosis.

METHODS

Retrospective monocentric cohort study. Patients with a PAT AHI ≥ 5/h followed by an in-hospital PSG within three months were included. All patients with a PAT AHI ≥ 5/h but a PSG AHI < 5/h were classified as discordant. Patients with PAT and PSG AHI ≥ 5/h were classified as concordant. To ascertain cardiovascular risk, major adverse cardiovascular events (MACE) were analyzed in discordant patients and sex, age, body mass index (BMI) and cardiovascular disease-matched concordant patients over a follow-up time of 3.1 ± 0.06 years.

RESULTS

A total of 940 patients, 66% male with an average age of 55 ± 0.4 years and BMI of 31 ± 0.2 kg/m² were included. Agreement in OSA diagnosis was observed in 80% of patients (55% in mild and 86% in moderate and severe OSA). Factors significantly associated with a discordant diagnosis were female sex, younger age and lower BMI, but not comorbidities. There was no significant difference in MACE (p = 0.920) between discordant patients (n = 155) and matched concordant patients (n = 274) with or without therapy.

CONCLUSIONS

Concordance between PAT and PSG diagnosis of sleep apnoea is good, particularly in moderate and severe OSA. Predictors for discordant results between PAT and PSG were age, sex and BMI. MACE risk is similar in those with OSA diagnosed by PAT or PSG.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

The effect of tongue elevation muscle training in patients with obstructive sleep apnea: A randomised controlled trial

BACKGROUND

Oropharyngeal myofunctional therapy is a multi-component therapy effective to reduce the severity of obstructive sleep apnoea (OSA). However, existing protocols are difficult to replicate in the clinical setting. There is a need to isolate the specific effectiveness of each component of the therapy.

OBJECTIVE

To assess the effects of a 6 weeks tongue elevation training programme in patients with OSA.

METHODS

We conducted a multicentre randomised controlled trial. Eligible participants were adults diagnosed with moderate OSA who presented low adherence to continuous positive airway pressure therapy (mean use <4 h per night). The intervention group completed a 6 weeks tongue elevation training protocol that consisted in anterior tongue elevation strength and endurance tasks with the Iowa Oral Performance Instrument. The control group completed a 6 weeks sham training protocol that involved expiratory muscle training at very low intensity. Polygraphy data, tongue force and endurance, and OSA symptoms were evaluated pre- and post-intervention. The primary outcome was apneoa-hypopnea index (AHI).

RESULTS

Twenty-seven patients (55 ± 11 years) were recruited. According to modified intention-to-treat analysis (n = 25), changes in AHI and c did not significantly differ between groups. Daytime sleepiness (Epworth Sleepiness Scale) and tongue endurance significantly improved in the intervention group compared to the control group (p = .015 and .022, respectively). In the intervention group, 75% of participants had a decrease in daytime sleepiness that exceeded the minimal clinically important difference.

CONCLUSION

Six weeks of tongue elevation muscle training had no effect on OSA severity.

Protocols for multimodal polygraphy for cardiorespiratory monitoring in the epilepsy monitoring unit. Part II - Research acquisition

Multimodal polygraphy including cardiorespiratory monitoring is a valuable tool for epilepsy and sudden unexpected death in epilepsy (SUDEP) research. Broader applications in research into stress, anxiety, mood and other domains exist. Polygraphy techniques used during video electroencephalogram (EEG) recordings provide information on cardiac and respiratory changes in the peri-ictal period. In addition, such monitoring in brain mapping during chronic intracranial EEG evaluations has helped the understanding of pathomechanisms that lead to seizure induced cardiorespiratory dysfunction. Our aim here is to provide protocols and information on devices that may be used in the Epilepsy Monitoring Unit, in addition to proposed standard of care data acquisition. These devices include oronasal thermistors, oronasal pressure transducers, capnography, transcutaneous CO2 sensors, and continuous noninvasive blood pressure monitoring. Standard protocols for cardiorespiratory monitoring simultaneously with video EEG recording, may be useful in the study of cardiorespiratory phenomena in persons with epilepsy.

Protocols for multimodal polygraphy for cardiorespiratory monitoring in the epilepsy monitoring unit. Part I: Clinical acquisition

Multimodal polygraphy including cardiorespiratory monitoring in the Epilepsy Monitoring is becoming increasingly important. In addition to simultaneous recording of video and EEG, the combination of these techniques not only improves seizure detection, it enhances patient safety and provides information on autonomic clinical symptoms, which may be contributory to localization of seizure foci. However, there are currently no consensus guidelines, nor adequate information on devices available for multimodal polygraphy for cardiorespiratory monitoring in the Epilepsy Monitoring Unit. Our purpose here is to provide protocols and information on devices for such monitoring. Suggested parameters include respiratory inductance plethysmography (thoraco-abdominal belts for respiratory rate), pulse oximetry and four-lead electrocardiography. Detailed knowledge of devices, their operability and acquisition optimization enables accurate interpretation of signal and differentiation of abnormalities from artifacts. Multimodal polygraphy brings new opportunities for identification of peri-ictal cardiorespiratory abnormalities, and may identify high SUDEP risk individuals.

Preoperative Assessment of Obstructive Sleep Apnea in Bariatric Patients Using Polysomnography or Polygraphy

BACKGROUND

Preoperative assessment of obstructive sleep apnea (OSA) in patients scheduled for bariatric surgery can be performed by in-laboratory polysomnography (PSG) or by portable polygraphy (PP) at home. We aimed to evaluate the association between PSG/PP, OSA diagnosis, and implementation of continuous positive airway pressure (CPAP) therapy.

METHODS

All patients who underwent bariatric surgery from 2015 to 2017 were retrospectively reviewed. Patients underwent preoperative PSG or PP, based on prevailing protocols or at the physician's discretion. Logistic regression analyses were performed to determine predictors of CPAP implementation. OSA-related postoperative complications were analyzed in both groups.

RESULTS

During the study period, 1464 patients were included. OSA was diagnosed in 79% of 271 patients undergoing PSG, compared to 64% of 1193 patients undergoing PP (p < 0.001), with median apnea-hypopnea index (AHI) of 15.8 and 7.7, respectively. CPAP treatment was initiated in 52% and 27% of patients, respectively, p < 0.001. Predictors (with adjusted odds ratio) in multivariate regression analysis for CPAP implementation were as follows: male gender (5.15), BMI ≥ 50 (3.85), PSG test (2.74), hypertension (2.38), and age ≥ 50 (1.87). OSA-related complications did not differ between groups (p = 0.277).

CONCLUSION

Both PSG and PP are feasible options for preoperative OSA assessment in bariatric patients. When PP is performed, some underdiagnosis may occur as cases of mild OSA may be missed. However, clinically relevant OSA is detected by both diagnostic tools. No difference in OSA-related complications was found. PP is a safe, less invasive option and can be considered as a suitable measure for OSA assessment in this population.

Sleep apnea and atrial fibrillation: challenges in clinical and translational research

INTRODUCTION

Sleep-disordered breathing (SDB) is present in 21-74% of all patients with atrial fibrillation (AF). Treatment of SDB by positive airway pressure may help to prevent recurrence of AF after electrical cardioversion and help to improve AF ablation success rates in non-randomized studies.

AREAS COVERED

In this review, the current understanding of the atrial arrhythmogenic pathophysiology of SDB is summarized, and diagnostic and therapeutic challenges in AF patients are discussed. Current international recommendations are presented, and a comprehensive literature search is undertaken.

EXPERT OPINION

AF patients with SDB rarely report SDB-related symptoms such as daytime sleepiness. Therefore, systematic home sleep testing evaluation should be considered for all patients eligible for rhythm control strategy. A close interdisciplinary collaboration between the electrophysiologist/cardiologist, nurses and sleep-specialists are required for the management of SDB in AF patients. An arrhythmia-orientated assessment of SDB may better quantify SDB-related AF risk in an individual patient and may help to better guide targeted and personalized SDB treatment in AF patients as a component of rhythm and symptom control strategies. Finally, randomized controlled trials are needed to confirm the relationship between SDB and AF, and the benefits of routine testing and treatment of SDB in AF patients.

Phenotyping OSAH patients during wakefulness

PURPOSE

Although currently there are simplified methods to measure the pathophysiological traits that stimulate the occurrence and maintenance of obstructive sleep apnea-hypopnea (OSAH), they remain difficult to implement in routine practice. This pilot study aimed to find a simpler daytime approach to obtain a meaningful, similar pathophysiological phenotypic profile in patients with OSAH.

METHODS

After obtaining diagnostic polygraphy from a group of consecutive patients with OSAH, we performed the dial-down CPAP technique during nocturnal polysomnography and used it as reference method. This allowed assessment of upper airway collapsibility, loop gain (LG), arousal threshold (AT), and upper airway muscle gain (UAG). We compared these results with a daytime protocol based on negative expiratory pressure (NEP) technique for evaluating upper airway collapsibility and UAG, on maximal voluntary apnea for LG, and on clinical predictors for AT.

RESULTS

Of 15 patients studied, 13 patients with OSAH accurately completed the two procedures. There were strong (all r² > 0.75) and significant (all p < 0.001) correlations for each phenotypic trait between the measurements obtained through the reference method and those achieved during wakefulness.

CONCLUSION

It is possible to phenotype patients with OSAH from a pathophysiological point of view while they are awake. Using this approach, cutoff values corresponding to those usually adopted using the reference method can be identified to detect abnormal traits, achieving profiles similar to those obtained through the dial-down CPAP technique.

Sleep position, patient comfort, and technical performance with two established procedures for home sleep testing

Purpose

In patients with a high pre-test probability of suffering from obstructive sleep apnea (OSA), (cardio)-respiratory polygraphy (RP; level 3) is commonly used for home sleep testing (HST); however, testing based on peripheral arterial tonometry (PAT) is increasingly recognized as an alternative method. The aim of the study was to compare sleep position, patients’ comfort, and technical failure rates of HST with RP and PAT in patients with suspected OSA.

Methods

Sleep position, patients’ comfort, and technical failure rates of RP and PAT were compared in 56 patients receiving two nights of HST with either RP or PAT in a randomized fashion.

Results

Time in supine position with PAT was significantly lower (173.7±88 min) compared to RP (181.7±103.7 min; p < 0.001), although the absolute mean difference was not clinically significant. Patients reported to sleep better, feeling less disturbed when falling asleep, losing less sensors, and fewer nightly awakenings with PAT, but experienced more pain at the side of the finger probe. Forty-five out of 56 patients (80%) rated PAT as being the superior sleep test and 49 out of 56 (88%) would prefer PAT for further investigations (p<0.001). PAT testing was associated with less technical failures.

Conclusion

The results demonstrate that HST with PAT leads to less time in supine sleep positioning, which may be clinically relevant in selected patients. Moreover, PAT is associated with less technical failures and is perceived with less discomfort during testing and a reduced number of nocturnal awakenings in patient self-reports.

Assessment of right ventricular remodeling and dysfunction in obstructive sleep apnea syndrome: a prospective monocentric study

BACKGROUND

Obstructive sleep apnea (OSA) is a common sleep-related disorder that has been implicated in many serious cardiovascular diseases including cardiac remodeling and dysfunction. Since most investigations have focused on the left heart, little is known on right ventricular (RV) involvement in OSA. The role of the RV in the management of cardiovascular outcomes has become increasingly recognized. Early detection of subtle signs of RV dysfunction and remodeling in patients with OSA is crucial for optimal medical care.

PURPOSE

We aimed to investigate the effect of OSA and its severity on the RV structure and function using conventional echocardiography.

METHODS

We conducted a cross-sectional analytical study including patients with OSA who did not have heart failure or chronic pulmonary disease comparing them to controls without OSA. All patients underwent respiratory polygraphy at the Pneumology Department and standard echocardiography performed by the same blinded cardiologist at the Cardiology Department of Taher Sfar University Hospital.

RESULTS

A total of 139 patients with OSA and 45 controls were enrolled in the study. Amonth the patients, there were 32% (n = 44) with mild, 20% (n = 28) with moderate, and 48% (n = 67) with severe OSA. Sixty-three percent of the study population were women. The mean age was 54.1 ± 11.0 years. Early RV dilatation was present in the mild disease stage (RVID = 42.0 ± 7.7 mm vs. 32.4 ± 5.5 mm in controls; p < 0.0001) without obvious RVH. The systolic pulmonary artery pressure was significantly higher in patients with OSA (31.2 ± 8.2 vs. 20.9 ± 9.8; p < 0.0001). Tricuspid annular plane systolic excursion was borderline normal and significantly lower in patients with OSA (17.7 ± 4.7 vs. 26.0 ± 5.7, p < 0.0001). In multivariate analysis, an OSA was independently associated with RV remodeling (OR: 0.257, 95% CI [0.114-0.582], p = 0.001) but not with RV dysfunction.

CONCLUSION

OSA was independently associated with structural alterations of RV early in the disease course, suggesting that the reversibility of these deleterious effects requires earlier detection and initiation of treatment.

Diagnostic approach to sleep disordered-breathing among patients with grade III obesity

Sleep apnea test (SAT) is a cost-effective approach to evaluate subjects without associated comorbidities suspected for obstructive sleep apnea (OSA), a disorder particularly common in obese subjects. The association of obesity with awake hypercapnia (carbon dioxide arterial pressure, PaCO₂ ≥45 mmHg) defines the obesity-hypoventilation syndrome (OHS), which in turn results in increased morbidity and mortality compared to simple OSA. Isolated hypoventilation during sleep in obese patients (obesity-related sleep hypoventilation, ORSH) is now considered as an early stage of OHS. The aim of this study was to assess the performance of SAT in diagnosing OSA and predicting the presence of ORHS among patients with grade III obesity without awake hypercapnia.

METHODS

Over a 14-months period, patients with grade III obesity (body mass index≥40 kg/m²) presenting moderate-to-severe OSA (apnea-hypopnea index [AHI]≥15) upon SAT and normal awake PaCO₂ at arterial blood gas analysis, systematically underwent in-lab nocturnal polysomnography combined with transcutaneous carbon dioxide pressure (PtcCO₂) monitoring.

RESULTS

Among 48 patients included in the study, 16 (33%) presented an AHI<15 upon polysomnography and 14 (29%) had ORSH. The test revealed no difference in ORSH prevalence between patients with AHI <15 or ≥15 (31% vs. 25%). No SAT variables were independently associated with increased PtCO₂.

CONCLUSIONS

This study shows that SAT overestimates OSA severity and ORSH affects one third of patients with grade III obesity without awake hypercapnia and with moderate-to-severe OSA at SAT, suggesting how polysomnography combined with PtCO₂ monitoring is the most appropriate diagnostic approach for OSA and ORSH in this population.

Complex home assessment of long-term non-invasive ventilation efficacy using transcutaneous monitoring of PCO2 and polygraphy - A feasibility study

PURPOSE

Home non-invasive ventilation (HNIV) during sleep is a standard treatment for chronic hypercapnic respiratory failure (CHRF). The aim of this study was to evaluate the feasibility of the complex overnight assessment of HNIV in adults performed at home and the efficacy of HNIV after one year of treatment.

METHODS

Stable patients with CHRF on HNIV for more than 12 months had unattended polygraphy (PG) with transcutaneous monitoring of PCO₂ (tcPCO₂) at home during one night. The recording quality was regarded as excellent when 100% and good if 80-99% of the analysis time was registered. The following efficacy criteria were approved: (1) SpO₂<90% for <10% of analysis time, (2) increase in PtcCO₂ ≤7.5 ​mmHg between baseline and average value at night, (3) apnea-hypopnea index (AHI) ≤5/h.

RESULTS

Eighteen patients with CHRF (median age 66 [60-74] years, 10 female) were included. The quality of the PG tracings was good to excellent in 16 (89%) patients and the quality of the tcPCO₂ data was good to excellent in 14 (78%) patients. There was no difference in the quality of tcPCO₂ between patients who lived alone and those who lived with family (100 [50-100]% vs. 100 [90-100]% of analysis time, respectively). Only 4 (22%) patients fulfilled all three efficacy criteria.

CONCLUSIONS

Home-based monitoring using PG and tcPCO₂ is a feasible and adequate tool to assess the efficacy of HNIV. In most of the patients on HNIV for more than 12 months, the treatment was not effective based on the predefined efficacy criteria.

Sleep Apnea and Atrial Fibrillation

Obstructive sleep apnea (OSA) creates a complex and dynamic substrate for atrial fibrillation (AF), which is characterized by structural remodeling as a result of long-term OSA as well as transient and acute apnea-associated transient atrial electrophysiological changes. OSA is present in 21% to 74% of patients with AF, and nonrandomized studies suggest that treatment of OSA by continuous positive airway pressure may help to maintain sinus rhythm after electrical cardioversion and improve catheter ablation success rates. Management of OSA in patients with AF requires a close interdisciplinary collaboration between the electrophysiologist/cardiologist and sleep specialists.

Comparison of the Apnea-Hypopnea Index Determined by a Peripheral Arterial Tonometry-Based Device With That Determined by Polysomnography - Results From a Multicenter Study

Background: Sleep disordered breathing (SDB) is prevalent and associated with increased mortality in patients both with and without cardiovascular disease (CVD). Many portable monitoring devices, including peripheral arterial tonometry (PAT)-based devices, have been developed. Although previous studies have demonstrated that the apnea-hypopnea index (AHI) determined by PAT devices (pAHI) is strongly correlated with AHI determined by polysomnography (AHI-PSG), no data have been reported from a Japanese patient population or patients with CVD. In this study we compared the parameters determined by PAT-based devices with those determined by polysomnography in Japanese patients with CVD.

Methods and Results: We enrolled 120 patients undergoing overnight polysomnography at 6 Japanese centers. A PAT-based device was used simultaneously with polysomnography. Polysomnography recordings were scored centrally by a technician in a blinded manner. PAT-based device recordings were scored using an automatic algorithm. There was a strong correlation between pAHI and AHI-PSG (r=0.896; P<0.001) with acceptable agreement. The strong correlation between pAHI and AHI-PSG was observed in patients with CVD (n=55; P=0.849; P<0.001) and without CVD (n=65; r=0.927; P<0.001). The presence or absence of CVD did not affect the relationship between pAHI and AHI-PSG (P=0.225).

Conclusions: A PAT-based device provides a reliable AHI in a Japanese patient population, even in patients with CVD. These findings may help reduce the number of patients with undiagnosed SDB and CVD.

The role of sleep laboratory polygraphy in the evaluation of obstructive sleep apnea syndrome in Robin infants

OBJECTIVE/BACKGROUND

Currently, obstructive sleep apnea syndrome (OSAS) management in Robin sequence (RS) infants has not been standardized. Sleep laboratory polysomnography (PSG) is the gold standard for OSAS diagnosis, however, access is restricted. This study aimed to compare the respiratory indexes measured in a sleep laboratory using PSG as well as a possible alternative, polygraphy (PG).

PATIENTS/METHODS

This retrospective study was conducted between 2015 and 2017 in a tertiary hospital. PSG performed in RS infants in the sleep laboratory was analysed by a single reviewer. After sleep data removal, anonymized raw data were analysed to obtain only PG data. Respiratory indexes were compared for (i) PSG and PG and (ii) patients with or without OSAS clinical signs.

RESULTS

Among the 20 RS (median [IQR] age: 43 [25-114] days at evaluation), 70% of the patients had OSAS clinical signs but all of them had severe OSAS. The median mixed obstructive apnea hypopnea index was not significantly different between PSG and PG (27/h [18-38] versus 26/h [18-56], p = 0.43). The median obstructive apnea index was higher with no significant difference between PG and PSG (19/h [15-31] versus 7/h [4-25], p = 0.05). The median obstructive hypopnea index was significantly lower on PG than on PSG (2/h [0-3] versus 8/h [8-19], p = 0.01). No difference on PSG or PG was observed for patients with and without clinical signs of OSAS.

CONCLUSION

Although PSG remains the gold standard for OSA evaluation, a PG seems to be a useful alternative to measure OSA in RS infants because of their OSAS severity. This evaluation should be recommended in all RS infants, even in the absence of OSAS clinical signs.

CLINICAL TRIAL REGISTRATION

Not applicable.

Lacunar stroke and heart rate variability during sleep

OBJECTIVE

Autonomic instability during sleep can influence the risk of cerebrovascular diseases. In this study, we performed a polygraphy to evaluate, heart rate variability (HRV) in a group of patients with lacunar stroke that is a condition at high risk of recurrence.

METHODS

Twenty-one lacunar stroke patients were enrolled one month after stroke occurrence. Sleep quality was assessed with the Pittsburgh Sleep Quality Index (PSQI). The presence of common sleep disorders and autonomic changes during the night was investigated by a polygraphy monitoring. Results were compared with those obtained in a group of 21 healthy subjects.

RESULTS

Patients and controls were similar for age, sex distribution and main cardiovascular risk factors with the exception of the body mass index. Significant differences were detected for all polysomnographic (PSG) parameters and for the PSQI score. By considering HRV values, patients with pathologic values (12 patients, HRV>2) showed significantly higher values in BMI (31 ± 2.9 vs. 26.6 ± 3.6, p = 0.006) and PSQI scores (7.9 ± 2.6 vs. 4.2 ± 1.9) with respect to patients with normal HRV values (nine patients, HRV≤2).

CONCLUSIONS

The results of this study suggest that the prevalence of nocturnal autonomic dysfunction is high in lacunar stroke patients even in the absence of the commonest sleep-related disorders. An abnormal HRV may contribute to increase the risk of stroke recurrence. Based on our results, the indication to polygraphy in patients with lacunar stroke should be carefully considered.

Successful home respiratory polygraphy to investigate sleep-disordered breathing in children

OBJECTIVE

Sleep-disordered breathing (SDB) in children is common. Interest in sleep tests, such as polygraphy (PG), which can be performed in a non-attended setting, are gaining is increasing. PG has, however, been little studied in children with co-morbidities other than obstructive sleep apnea (OSA), and in particular, if performed in a non-attended setting. We report on the feasibility and interpretability of implementing PGs at home versus in hospital.

METHODS

PGs were analyzed according to the setting (hospital or home) and sequence (initial or subsequent) in which they were performed. Non-interpretability was defined as absent or unreliable oxygen saturation by pulse oximetry (SpO₂), or airflow and respiratory inductance plethysmography flow trace signals during the time analyzed.

RESULTS

We retrospectively analyzed 400 PGs; 332/400 were initial PGs. Indications were: suspected OSA (65%), obesity (13%), craniofacial malformations (5%), neuromuscular disease (4%), and other (13%) which included prematurity. 16% were recorded in hospitals and 84% at home. The mean age was 5.7 ± 5.8 years and 7.3 ± 4.5 years for the hospital and home groups, respectively. Interpretability was similar in both settings (87%). In the 68 subsequent PGs, interpretability was 84% when performed for follow-up and 96% when repeated for non-interpretability. Non-interpretability was predominantly due to a failure of the SpO₂ channel.

CONCLUSIONS

PG performed at home is both feasible and interpretable for a variety of indications. Non-interpretability was not predictable in association with the setting, anthropometric data, or indication, independently of the sequence (initial or subsequent PG) in which the parameters were analyzed.

[Sleep-related breathing disorders in children and teenagers: diagnosis, consequences and comorbidities]

Obstructive sleep apnoea syndrome (OSAS) is a frequent sleep-related breathing disorder in children with a prevalence of approximately 3% between the ages of 3 and 8. Its origin is multifactorial (hypertrophy of pharyngeal soft tissues, narrowing of the bone airways, damage to the neuromuscular tone). The symptoms and clinical signs to look for during the day and at night are directly related to upper airway (UA) obstruction or poor sleep quality. After a complete anamnestic and clinical evaluation, including nasofibroscopy, the ENT specialist will refer to an adeno-amygdalectomy or night recording by polysomnography or polygraph to confirm the diagnosis in the child. Among adolescents, the prevalence of OSAS is reported to be between 0.5 and 6%. The main risk factors are obesity, male sex and a history of tonsillectomy. In addition to the classic symptoms of childhood OSAS, this syndrome may, in adolescents, manifest itself as a misleading semiology of dyssomnia, excessive daytime sleepiness and/or mood disorders. Differential diagnoses with risk behaviours, phase delay or narcolepsy should be systematically discussed. It is essential to record breathing during sleep. Even if the obstructive apnea/hypopnea index is low, it must be considered. In both children and adolescents, multidisciplinary management (ENT, orthodontist, maxillofacial physiotherapist, pulmonologist) should be early in order to avoid neurocognitive, behavioural, cardiovascular and metabolic complications. Maxillofacial surgery can be discussed from the age of 15. It is important not to forget to pay attention to the rules of healthy living and sleep as well as the management of obesity.

[Sleep-related breathing disorders in children and teenagers: diagnosis, consequences and comorbidities]

Obstructive sleep apnoea syndrome (OSAS) is a frequent sleep-related breathing disorder in children with a prevalence of approximately 3% between the ages of 3 and 8. Its origin is multifactorial (hypertrophy of pharyngeal soft tissues, narrowing of the bone airways, damage to the neuromuscular tone). The symptoms and clinical signs to look for during the day and at night are directly related to upper airway (UA) obstruction or poor sleep quality. After a complete anamnestic and clinical evaluation, including nasofibroscopy, the ENT specialist will refer to an adeno-amygdalectomy or night recording by polysomnography or polygraph to confirm the diagnosis in the child. Among adolescents, the prevalence of OSAS is reported to be between 0.5 and 6%. The main risk factors are obesity, male sex and a history of tonsillectomy. In addition to the classic symptoms of childhood OSAS, this syndrome may, in adolescents, manifest itself as a misleading semiology of dyssomnia, excessive daytime sleepiness and/or mood disorders. Differential diagnoses with risk behaviours, phase delay or narcolepsy should be systematically discussed. It is essential to record breathing during sleep. Even if the obstructive apnea/hypopnea index is low, it must be considered. In both children and adolescents, multidisciplinary management (ENT, orthodontist, maxillofacial physiotherapist, pulmonologist) should be early in order to avoid neurocognitive, behavioural, cardiovascular and metabolic complications. Maxillofacial surgery can be discussed from the age of 15. It is important not to forget to pay attention to the rules of healthy living and sleep as well as the management of obesity.

How Relevant Is Pre-operative Obstructive Sleep Apnoea in the Asymptomatic Bariatric Surgery Patient?

INTRODUCTION

The American Academy of Sleep Medicine recommends patients attending for bariatric surgery (BS) to be evaluated for obstructive sleep apnoea (OSA) as untreated OSA is associated with a greater risk of post-operative complications. Not all bariatric patients have symptoms of OSA and their phenotype may be at less risk than the typical sleep clinic phenotype. Therefore, all patients may not require pre-operative sleep studies. This study aimed to establish whether screened and unscreened BS patients are at increased risk of post-operative complications.

METHODS

A retrospective review of BS patients at a single centre, June 2008-May 2017. Demographic data, sleep study outcomes, post-operative complications, length of stay (LOS), intensive care unit (ICU) admission, and readmission rates were reviewed.

RESULTS

A total of 510 patients underwent gastric bypass, sleeve gastrectomy, or gastric banding. 385/510 (75.5%) were female. Mean age was 46 ± 11.27 years, mean BMI was 49 kg/m² ± 7.42. OSA was diagnosed in 300/510 (58.8%) and normal sleep in 57/510 (11.2%). OSA was not associated with increased post-operative complications. No significant difference between screened and unscreened patients for the development of post-operative pulmonary or cardiac complications, (p = 0.607, p = 0.827, respectively). Increasing age was a predictor for pulmonary (p = 0.011) and cardiac (p = 0.018) complications.

CONCLUSION

OSA is very prevalent in morbidly obese patients. The lack of association between patients diagnosed with OSA and unscreened patients, and post-operative complications suggests that not all patients require pre-operative sleep studies. Further studies may help identify which patients can safely avoid OSA screening.

Connectivity measures suggest a sub-cortical generator of myoclonus in Angelman syndrome

OBJECTIVE

The clinical and neurophysiological characteristics of myoclonus in Angelman syndrome (AS) have been evaluated in single case or small cohorts, with contrasting results. We evaluated the features of myoclonus in a wide cohort of AS patients.

METHODS

We performed polygraphic EEG-EMG recording in 24 patients with genetically confirmed AS and myoclonus. Neurophysiological investigations included jerk-locked back-averaging (JLBA), cortico-muscular coherence (CMC) and generalised partial directed coherence (GPDC). CMC and GPDC analyses were compared to those obtained from 10 healthy controls (HC).

RESULTS

Twenty-four patients (aged 3-35 years, median 20) were evaluated. Sequences of quasi-continuous rhythmic jerks mostly occurred at alpha frequency or just below (mean 8.4 ± 1.4 Hz), without EEG correlate. JLBA did not show any clear transient preceding the jerks. CMC showed bilateral over-threshold CMC in alpha band that was prominent on the contralateral hemisphere in the patient group as compared to HC group. GPDC showed a significantly higher alpha outflow from both hemispheres toward activated muscles in the patient group, and a significantly higher beta outflow from contralateral hemisphere in the HC group.

CONCLUSIONS

These neurophysiological findings suggest a subcortical generator of myoclonus in AS.

SIGNIFICANCE

Myoclonus in AS has not a cortical origin as previously hypothesised.

New insights in phenomenology and treatment of epilepsy in CDKL5 encephalopathy

Eight patients, seven girls and one boy, had CDKL5 gene mutation, duplication, or deletion. Epileptic spasms started at a mean age of 3.5 months (range = 4 weeks-8 months). In five cases, tonic seizures preceded spasms at a median age of 6 weeks. In one patient who started at 8 months, spasms had a component of terror on awakening, reminding sleep terror. In two patients, electroencephalogram polygraphy of a so-called tonic seizure revealed that the tonic phase was followed by an overlooked clonic phase and then by a cluster of spasms during which each spasm was preceded by a brief clonic jerk revealed by electromyography. This sequence is rather particular and can be an early diagnostic clue. Progressive transition from this seizure type to epileptic spasms in clusters seems to result from increasing expression of the CDKL5 gene, as the child grows older. Five patients responded to the combination of vigabatrin and zonisamide.

Spontaneous yawning in patients with multiple sclerosis: A polygraphic study

BACKGROUND

Patients with multiple sclerosis (MS) suffer from the repetitive yawning and sleep problems. Yawning is observed in MS and other central nervous system disorders and yawning and swallowing may be controlled by the network of the brain stem. Therefore it is important to investigate the MS patients with various clinical and radiological locations in order to understand the role of brainstem on the yawning mechanisms. One hour polygraphic recording would be crucial method for this purpose, because it is easy to observe spontaneous yawning (SY) and spontaneous swallowing (SS) together with their electrophysiologic counterparts. Previous studies reported that contagious yawn and swallow are temporally related and frequency of swallows was increased within 10s of post yawn period in normal adult subjects. We have re-investigated this phenomenon by studying the SY and SS in polygraphic recording in normal subjects and patients with MS. Then we hypothesized that SY is expected to be increased in MS patients.

METHODS

49 patients with MS and 19 control subjects were recruited in this study. We used a twelve-channel electroencephalography (EEG) device. Five channels were for electromyography (EMG) recording. We also used one channel for laryngeal sensor for vertical movements of the larynx during swallowing. Cardiac rhythm, respiration and sympathetic skin responses were synchronously recorded during swallowing. We evaluated rate of total SY, swallows inside the yawning, before and after 10s of the yawning and yawning unrelated with swallowing.

RESULTS

Patients with MS yawned more frequently than healthy controls (p = 0,044). It was obvious that the yawning unrelated with spontaneous swallow was also significantly increased compared to normal controls (p = 0,047), whereas swallowing inside the yawn or before and after 10s of yawning were not significantly different in both groups. Among 49 MS patients, 16 (32.6%) had brainstem involvement. Yawning was observed in only 6 (37.5%) of them.

CONCLUSION

Yawning is significantly increased in MS patients compared to normal controls by using the polygraphic method. There is no direct relation of the brainstem and the origin of yawning in MS patients according to clinical picture and MRI findings. However safe swallows during yawning could suggest that there is still need to some brain stem mechanism and/or oropharyngeal reflexes. Difficulties must be emphasized to detect anatomic localization in MS because of relapsing pattern of disease.

Oxygen and carbon dioxide monitoring during sleep

Monitoring of oxygen and carbon dioxide (CO₂) is of crucial importance during sleep-disordered breathing in order to assess the consequences of respiratory events on gas exchange. Pulse oximetry (SpO₂) is a simple and cheap method that is used routinely for the recording of oxygen levels and the diagnosis of hypoxemia. CO₂ recording is necessary for the diagnosis of alveolar hypoventilation and can be performed by means of the end-tidal (PetCO₂) or transcutaneous CO₂ (PtcCO₂). However, the monitoring of CO₂ is not performed on a routine basis due to the lack of simple, cheap and reliable CO₂ monitors. This short review summarizes some technical aspects of gas exchange recording during sleep in children before discussing the different definitions of alveolar hypoventilation and the importance of CO₂ recording.

Sleep study as a diagnostic tool for unexplained respiratory failure in infants hospitalized in the PICU

PURPOSE

The aim of the study was to analyze the diagnostic and therapeutic value of a polygraphy (PG) in infants hospitalized for unexplained respiratory failure or life-threatening events in the PICU.

MATERIAL AND METHODS

The PG of 13 infants (4 girls), mean age 6.8±7.7months, were analyzed.

RESULTS

Eight infants were admitted for unexplained respiratory failure and 5 for life-threatening events. PG showed features suggestive of respiratory muscle weakness in 5 infants whose final diagnoses were nemaline rod myopathy (n=2), congenital myasthenia (n=2), and diaphragmatic dysfunction (n=1). Four of these patients were successfully treated with noninvasive ventilation (NIV). PG was suggestive of brainstem dysfunction in 4 infants; 2 were treated successfully with NIV and another with caffeine. PG showed obstructive sleep apnea in 3 infants; 2 were treated successfully with NIV and one patient was lost during follow up. A typical pattern of congenital central hypoventilation syndrome was observed in the last patient who was treated successfully with invasive ventilation. One patient with diaphragmatic dysfunction and one with brain stem dysfunction died.

CONCLUSIONS

PG may assist the diagnosis and guide the management of unexplained respiratory failure or life-threatening events in infants hospitalized in the PICU.

[Hypertension and cardiovascular risk associated with obstructive sleep apnea in adult in Guadeloupe (French West Indies)]

BACKGROUND AND PURPOSE

In Guadeloupe, data on the relationships between arterial hypertension and obstructive sleep apnea are unavailable. The aim of this study was: to assess the frequency of hypertension and non-dipper pattern evaluated by 48-hour ambulatory blood pressure monitoring in an adult population identified obstructive sleep apnea/non-obstructive sleep apnea during overnight polygraphy ; to determine the cardio-metabolic factors associated with obstructive sleep apnea.

DESIGN AND METHOD

A cross-sectional study was realized at Pointe-à-Pitre Hospital. Patients were referred for suspected sleep apnea to sleep specialist and performed a nocturnal polygraphy. Diagnosis was confirmed if the apnea-hypopnea index was ≥ 5. We obtained two groups: sleep apnea/non-sleep apnea. All patients underwent 48-hour ambulatory blood pressure monitoring. The cardio-metabolic factors were identified and assessed (fasten level of hs-CRP and Homa-IR index).

RESULTS

A total of 204 patients were included. Mean age at diagnosis was 54 ± 10 years, 63% were women. OSA was present in 69.6% with a higher frequency in men than in women. Difference was not significant between the two groups for hypertension frequency (84.5% vs 77%; P=0.22), non-dipper pattern (77.5% vs 76%; P=0.79) and hs-CRP. Differences for age, snoring, body max index, mean waist circumference, Homa-IR index, obesity, dyslipidemia, and type 2 diabetes were significant.

CONCLUSIONS

Our data highlight raised frequency of cardiovascular metabolic factors in patients with obstructive sleep apnea and confirm their high cardiovascular risk.

Spinal muscular atrophy associated with progressive myoclonic epilepsy: A rare condition caused by mutations in ASAH1

OBJECTIVE

To present the clinical features and the results of laboratory investigations in three patients with spinal muscular atrophy associated with progressive myoclonic epilepsy (SMA-PME), a rare condition caused by mutations in the N-acylsphingosine amidohydrosilase 1 (ASAH1) gene.

METHODS

The patients were submitted to clinical evaluation, neurophysiologic investigations (that included wakefulness and sleep electroencephalography [EEG], video-polygraphic recording with jerk-locked back-averaging, multimodal evoked potentials, and electromyography), brain magnetic resonance imaging (MRI), biochemical screening, muscle and skin biopsies, and molecular genetic analysis.

RESULTS

The main clinical features were onset in childhood with proximal muscular weakness, generalized epilepsy with absences and myoclonic seizures, cognitive impairment of variable degree; the course was progressive with muscle wasting and uncontrolled epileptic seizures. In one patient, earlier onset before the age of 2 years was associated with a more complex clinical picture, with abnormal eye movements, progressive cognitive impairment, and a more rapid and severe course. EEG/polygraphic data were consistent with PME, demonstrating generalized spike-and-wave discharges, evidence of positive and negative myoclonia, and prominent photosensitivity. In one patient, transcranial magnetic stimulation showed a hyperexcitable motor cortex, whereas somatosensory evoked potentials were unaffected. Possible involvement of the central acoustic and visual pathways was suggested by abnormal auditory and visual evoked potentials. Muscle biopsies showed typical signs of neurogenic damage. Molecular genetic analysis showed mutations of the ASAH1 gene.

SIGNIFICANCE

Our data indicate that SMA-PME associated with ASAH1 mutations is a genetically distinct condition with specific clinical and neurophysiologic features. Further studies are warranted to explore the role of the ASAH1 gene in muscle and brain function.