Velopharyngeal dysfunction in children with Prader-Willi syndrome after adenotonsillectomy

Diagnosis and management of sleep disorders in Prader-Willi syndrome

Clinical experience and a growing body of evidence suggest that sleep disturbances are common in people with Prader-Willi syndrome (PWS). PWS is a rare neuroendocrine disorder characterized by early hypotonia and feeding difficulties; developmental delays; endocrinopathies; and behavioral concerns, especially rigidity, anxiety, and behavioral outbursts. PWS is also characterized by decreased resting energy expenditure and transition to hyperphagia and obesity. We propose that, for many people with PWS, clinical diagnosis and management of sleep disorders is an unmet need. We present current information to suggest disordered sleep is a significant burden for individuals with PWS and often overlooked. While central and obstructive sleep apnea are more widely recognized in PWS, other sleep disorders have increasingly gained recognition, including hypersomnia, narcolepsy-like phenotypes, and insomnia. Sleep disorders can impact behavior, cognition, and quality of life and health for individuals with PWS. Our goal is to bring sleep disorders to the forefront of therapeutic intervention for patients with PWS. This paper presents a review of the literature and recommendations for clinical practice based on published research and our clinical experience as sleep specialists, geneticists, psychiatrists, pediatricians, otolaryngologists, and pulmonologists with extensive experience with this patient population. We recommend that management of sleep be considered an integral part of successful medical management of PWS. Further research concerning sleep problems in PWS is urgently needed to develop best practices and work toward a consensus statement for medical management to meet the needs of people with PWS.

CITATION

Duis J, Pullen LC, Picone M, et al. Diagnosis and management of sleep disorders in Prader-Willi syndrome. J Clin Sleep Med. 2022;18(6):1687-1696.

Sleep Disorders in Children with Prader Willi Syndrome: Current Perspectives

Children with Prader-Willi syndrome (PWS) face a multitude of potential health challenges including life-threatening obesity, endocrinopathies, behavioral and emotional dysregulation, developmental delays, and sleep disorders. In the current perspective piece, we provide a focused review of the condition's etiology and clinical findings, as well as a more in-depth discussion of sleep disorders frequently associated with PWS. In particular, we highlight and discuss difficult clinical scenarios frequently encountered by the pediatric sleep physician caring for this patient population, including diagnosis and treatment of complex sleep-related breathing disorders, considerations for sleep apnea surgery, the interplay between growth hormone and sleep apnea, diagnostic challenges in hypersomnia/narcolepsy, and current and emerging therapies for hypersomnia/narcolepsy. Overall, although there are many areas that need further research, sleep disorders remain a fruitful target for improving quality of life of children with PWS and their families.

Sleep disorders in Prader-Willi syndrome, evidence from animal models and humans

Prader-Willi Syndrome (PWS) is a complex genetic disorder with multiple cognitive, behavioral and endocrine dysfunctions. Sleep alterations and sleep disorders such as Sleep-disordered breathing and Central disorders of hypersomnolence are frequently recognized (either isolated or in comorbidity). The aim of the review is to highlight the pathophysiology and the clinical features of sleep disorders in PWS, providing the basis for early diagnosis and management. We reviewed the genetic features of the syndrome and the possible relationship with sleep alterations in animal models, and we described sleep phenotypes, diagnostic tools and therapeutic approaches in humans. Moreover, we performed a meta-analysis of cerebrospinal fluid orexin levels in patients with PWS; significantly lower levels of orexin were detected in PWS with respect to control subjects (although significantly higher than the ones of narcoleptic patients). Sleep disorders in humans with PWS are multifaceted and are often the result of different mechanisms. Since hypothalamic dysfunction seems to partially influence metabolic, respiratory and sleep/wake characteristics of this syndrome, additional studies are required in this framework.

Outcomes of Adenotonsillectomy for Obstructive Sleep Apnea in Prader-Willi Syndrome: Systematic Review and Meta-analysis

OBJECTIVES

Prader-Willi syndrome (PWS) increases the risk of obstructive sleep apnea (OSA) due to obesity, hypotonia, and abnormal ventilatory responses. We evaluated post-adenotonsillectomy complications, polysomnography changes, and quality of life in children with OSA and PWS.

STUDY DESIGN

Systematic review and meta-analysis.

METHODS

We conducted a systematic review and meta-analysis by searching PubMed, Embase, Cochrane, Web of Science, and Scopus. Two researchers independently reviewed studies about adenotonsillectomy for OSA in patients <21 years with PWS. We extracted study design, patient numbers, age, complications, polysomnography, and quality of life. We pooled postoperative changes in apnea hypopnea index (AHI) for meta-analysis. We applied Methodological Index for Nonrandomized Studies (MINORS) criteria to assess study quality.

RESULTS

The initial search yielded 169 studies. We included 68 patients from eight studies with moderate to high risk of bias. Six studies reported on complications and 12 of 51 patients (24%) had at least one. Velopharyngeal insufficiency was the most commonly reported complication (7/51, 14%). We included seven studies in meta-analysis. Mean postoperative improvement in AHI was 7.7 (95% CI: 4.9-10.5). Postoperatively 20% (95% CI: 3%-43%) had resolution of OSA with AHI < 1.5 while 67% (95% CI: 50%-82%) had improvement from severe/moderate OSA to mild/resolved (AHI < 5). Two studies evaluated quality of life and demonstrated improvement.

CONCLUSIONS

Children with PWS undergoing adenotonsillectomy for OSA have a substantial risk of postoperative complications that may require additional interventions, especially velopharyngeal insufficiency. Despite improvements in polysomnography and quality of life, many patients had residual OSA. This information can be used to counsel families when considering OSA treatment options. Laryngoscope, 131:898-906, 2021.

Adenotonsillectomy for the Treatment of Obstructive Sleep Apnea in Children with Prader-Willi Syndrome: A Meta-analysis

Objective

Adenotonsillectomy outcomes in obstructive sleep apnea (OSA) treatment among children with Prader-Willi syndrome (PWS) remain unclear. This study aimed to elucidate the effectiveness of adenotonsillectomy in OSA treatment among children with PWS.

Data Source

PubMed, MEDLINE, Embase, and Cochrane Review up to February 2019.

Review Methods

The registry number of the protocol published on PROSPERO was CRD42015027053. Two authors independently searched the relevant database. Polysomnography outcomes in these children were examined, including net postoperative changes in the apnea-hypopnea index (AHI), net postoperative changes in the minimum and mean oxygen saturation, the overall success rate for a postoperative AHI <1, and the overall success rate for a postoperative AHI <5.

Results

Six studies with 41 patients were analyzed (mean age, 5.0 years; 55% boys; mean sample size, 6.8 patients). All children had PWS and received adenotonsillectomy for the treatment of OSA. The AHI was 13.1 events per hour (95% CI, 11.0-15.1) before surgery and 4.6 events per hour (95% CI, 4.1-5.1) after surgery. The mean change in the AHI was a significant reduction of 8.0 events per hour (95% CI, −10.8 to −5.1). The overall success rate was 21% (95% CI, 11%-38%) for a postoperative AHI <1 and 71% (95% CI, 54%-83%) for a postoperative AHI <5. Some patients developed velopharyngeal insufficiency postoperatively.

Conclusion

Adenotonsillectomy was associated with OSA improvement among children with PWS. However, residual OSA was frequently observed postoperatively in these patients.

Sleep-disordered breathing in paediatric setting: existing and upcoming of the genetic disorders

Childhood obstructive sleep apnea syndrome (OSAS) is characterized by anatomical and functional upper airway abnormalities as pathophysiological determinants, and clinical symptoms are frequently clear. OSAS is widely described in rare genetic disorders, such as achondroplasia, Down syndrome, Prader-Willi syndrome, Pierre Robin sequence, and mucopolysaccharidosis. Craniofacial and upper airway involvement is frequently morbid conditions. In children with genetic diseases, the clinical symptoms of OSAS are often slight or absent, and related morbidities are usually more severe and can be observed at any age. The present review is aimed to updating the discoveries regarding OSAS on Achondroplasia, Down syndrome, Prader-Willi syndrome, Pierre Robin sequence, Sickle cell disease, or encountered in our clinical practice (Ehlers-Danlos syndrome, Ellis-van Creveld syndrome, Noonan syndrome). Two additional groups of genetic disorders will be focused (mucopolysaccharidoses and osteogenesis imperfecta). The flowing items are covered for each disease: (I) what is the pathophysiology of OSAS? (II) What is the incidence/prevalence of OSAS? (III) What result from the management and prognosis? (IV) What are the recommendations? Considering the worries of OSAS, such as inattention and behavioural problems, daytime sleepiness, failure to thrive, cardiological and metabolic complications, the benefit of a widespread screening and the treatment in children with genetic diseases is undoubtful. The goals of the further efforts can be the inclusion of various genetic diseases into guidelines for the screening of OSAS, updating the shreds of evidence based on the research progression.

Effectiveness of Adenotonsillectomy and Risk of Velopharyngeal Insufficiency in Children With Prader-Willi Syndrome

Objectives:

(1) Review effectiveness of adenotonsillectomy (T&A) for obstructive sleep apnea (OSA) in children with Prader-Willi syndrome (PW). (2) Examine the incidence of velopharyngeal insufficiency (VPI) after T&A in this population. (3) Compare outcomes of T&A in PW and Trisomy 21 (T21) patients.

Methods:

Outcomes after T&A in a PW cohort were retrospectively reviewed and compared to those in patients with T21.

Results:

The study cohort included 22 PW patients. They were compared to 47 T21 patients who also underwent T&A. Eighteen percent (N = 4) of the PW patients had postoperative VPI requiring a corrective procedure, while there were no patients within the T21 cohort who had identified VPI ( P < .05). In those patients that had a postoperative polysomnogram, the mean decrease in obstructive apnea-hypopnea index (OAHI) of the PW and T21 patients measured 8.4 and 4.7 points, respectively ( P = .3).

Conclusions:

This study demonstrated a higher rate of VPI after T&A in PW children as compared to another at-risk cohort, T21 patients. While the OAHI decreased after T&A in both groups, a significant number of children with PW or T21 had persistent OSA. Further investigation into the optimal management of OSA, while preventing treatment complications such as VPI, is needed for children with these high-risk conditions

Adenotonsillectomy to treat obstructive sleep apnea: Is it enough?

Although adenotonsillectomy is the first line treatment for children with obstructive sleep apnea syndrome (0SAS),¹ improvement in objectively documented outcomes is often inadequate and a substantial number of children have residual disease. Early recognition and treatment of children with persistent OSAS is required to prevent long-term morbidity. The management of these children is frequently complex and a multidisciplinary approach is required as most of them have additional risk factors for OSAS and comorbidities. In this paper, we first provide an overview of children at risk for persistent disease following adenotonsillectomy. Thereafter, we discuss different diagnostic modalities to evaluate the sites of persistent upper airway obstruction and the currently available treatment options. Pediatr Pulmonol. 2017;52:699-709. © 2016 Wiley Periodicals, Inc.

Respiratory Complications in Children with Prader Willi Syndrome

Prader Willi syndrome, resulting from the partial deletion or lack of expression of a region of genes on the paternal chromosome 15, has a number of phenotypic features which predispose affected patients to ventilatory problems. These include generalised hypotonia, abnormal arousal and ventilatory responses to hypoxia and hypercapnia, scoliosis and frequently, obesity. The spectrum of the resulting respiratory complications thus runs from sleep disordered breathing, to aspiration and respiratory functional impairment. While the use of growth hormone, in conjunction with multidisciplinary clinical management, is currently the cornerstone of clinical care of these patients, concerns have been raised following reports of sudden death shortly after growth hormone initiation. This review summarizes the respiratory complications commonly seen and draws together the published literature on the impact of growth hormone in relation to various respiratory parameters, aiming to provide the reader with the necessary information to manage these patients as safely as possible.

Disorders of Sleep and Ventilatory Control in Prader-Willi Syndrome

Prader-Willi syndrome (PWS) is an imprinted genetic disorder conferred by loss of paternal gene expression from chromosome 15q11.2-q13. Individuals with PWS have impairments in ventilatory control and are predisposed toward sleep disordered breathing due to a combination of characteristic craniofacial features, obesity, hypotonia, and hypothalamic dysfunction. Children with PWS progress from failure to thrive during infancy to hyperphagia and morbid obesity during later childhood and onward. Similarly, the phenotype of sleep disordered breathing in PWS patients also evolves over time from predominantly central sleep apnea in infants to obstructive sleep apnea (OSA) in older children. Behavioral difficulties are common and may make establishing effective therapy with continuous positive airway pressure (CPAP) more challenging when OSA persists after adenotonsillectomy. Excessive daytime sleepiness (EDS) is also common in patients with PWS and may continue after OSA is effectively treated. We describe here the characteristic ventilatory control deficits, sleep disordered breathing, and excessive daytime sleepiness seen in individuals with PWS. We review respiratory issues that may contribute to sudden death events in PWS patients during sleep and wakefulness. We also discuss therapeutic options for treating sleep disordered breathing including adenotonsillectomy, weight loss, and CPAP. Lastly, we discuss the benefits and safety considerations related to growth hormone therapy.

Prader-Willi syndrome: a review of clinical, genetic, and endocrine findings

INTRODUCTION

Prader-Willi syndrome (PWS) is a multisystemic complex genetic disorder caused by lack of expression of genes on the paternally inherited chromosome 15q11.2-q13 region. There are three main genetic subtypes in PWS: paternal 15q11-q13 deletion (65-75 % of cases), maternal uniparental disomy 15 (20-30 % of cases), and imprinting defect (1-3 %). DNA methylation analysis is the only technique that will diagnose PWS in all three molecular genetic classes and differentiate PWS from Angelman syndrome. Clinical manifestations change with age with hypotonia and a poor suck resulting in failure to thrive during infancy. As the individual ages, other features such as short stature, food seeking with excessive weight gain, developmental delay, cognitive disability and behavioral problems become evident. The phenotype is likely due to hypothalamic dysfunction, which is responsible for hyperphagia, temperature instability, high pain threshold, hypersomnia and multiple endocrine abnormalities including growth hormone and thyroid-stimulating hormone deficiencies, hypogonadism and central adrenal insufficiency. Obesity and its complications are the major causes of morbidity and mortality in PWS.

METHODS

An extensive review of the literature was performed and interpreted within the context of clinical practice and frequently asked questions from referring physicians and families to include the current status of the cause and diagnosis of the clinical, genetics and endocrine findings in PWS.

CONCLUSIONS

Updated information regarding the early diagnosis and management of individuals with Prader-Willi syndrome is important for all physicians and will be helpful in anticipating and managing or modifying complications associated with this rare obesity-related disorder.