Update on pathophysiology and treatment of childhood obstructive sleep apnea syndrome

Awareness and attitude among general dentists and orthodontists toward obstructive sleep apnea in children

Aim

This study aimed to investigate Italian dentists' knowledge of and attitudes toward obstructive sleep apnea (OSA) in children.

Methods

An anonymous questionnaire was prepared using Google Forms and sent to dentists in Italy through private social platforms. The first part of the questionnaire contained basic demographic data questions, and the second part included items about pediatric OSA.

Results

A total of 125 responses were collected within 1 month. The interviews revealed gaps in undergraduate and post-graduate training on OSA, and consequently, low self-evaluation of knowledge and self-confidence in managing young patients with OSA. Dentists showed unfavorable attitudes and poor knowledge of the general findings, risk factors, and consequences of pediatric OSA but demonstrated good knowledge of the beneficial effects of rapid maxillary expansion. Orthodontists showed a more favorable attitude and better recognition of the craniofacial features associated with OSA. In addition, a comparison was made between dentists who had graduated more than 5 years ago and new graduates, and differences were found in undergraduate education, which was better for new graduates, and a small number of questions were better answered by experienced dentists.

Conclusion

This study showed a lack of knowledge about pediatric OSA and its management among Italian dentists, revealing the need to update the dentistry curriculum and organize educational interventions.

An Obstructive Sleep Apnea - A Novel Public Health Threat

In patients with obstructive sleep apnea (OSA) during obstructive events, episodes of hypoxia and hypercapnia may modulate the autonomic nervous system (ANS) by increasing sympathetic tone and irritability, which contributes to sympathovagal imbalance and ultimately dysautonomia. Because OSA can alter ANS function through biochemical changes, we can assume that heart rate variability (HRV) will be altered in patients with OSA. Most studies show that in both the time and frequency domains, patients with OSA have higher sympathetic components and lower parasympathetic dominance than healthy controls. These results confirm autonomic dysfunction in these patients, but also provide new therapeutic directions. Respiratory methods that modulate ANS, e.g., cardiorespiratory biofeedback, could be beneficial for these patients. Heart rate variability assessment can be used as a tool to evaluate the effectiveness of OSA treatment due to its association with autonomic impairment.

Sleep Disorders in Childhood

OBJECTIVE

This article provides a comprehensive review of pediatric sleep disorders including the clinical features, diagnosis, and treatment of sleep-disordered breathing, insomnia, parasomnias, restless sleep disorder, restless legs syndrome, narcolepsy in childhood, and Kleine-Levin syndrome.

LATEST DEVELOPMENTS

Our understanding of pediatric sleep pathophysiology continues to evolve, and diagnostic and treatment modalities have expanded. A low-sodium oxybate formulation was approved in July 2020 in the United States to treat cataplexy and excessive daytime sleepiness in patients 7 years old and older with narcolepsy. A validated pediatric hypersomnolence survey for pediatric narcolepsy and idiopathic hypersomnia with high sensitivity, specificity, and interrater reliability is now available.

ESSENTIAL POINTS

The clinical presentation, diagnostics, and treatment of children with sleep disorders differ from those of adults. Untreated sleep disorders in childhood can lead to adverse physical and psychological consequences in adults. Correctly diagnosing and treating sleep disorders in youth can prevent a significant burden of disease in adulthood.

Craniofacial Morphologic Predictors for Passive Myofunctional Therapy of Pediatric Obstructive Sleep Apnea Using an Oral Appliance with a Tongue Bead

We conducted this retrospective study to identify potential clinical, polysomnographic, and cephalometric predictors for the treatment outcomes of a tongue-beaded oral appliance (OA) in children with obstructive sleep apnea syndrome (OSAS). In total, 63 patients—50 boys and 13 girls ranging in age from 4 to 16 years—underwent OA treatment nightly for at least 6 months. A baseline digital lateral cephalometric radiograph was obtained for each patient. Multivariate logistic regression analysis was performed to examine predictors for the treatment outcome based on the clinical and cephalometric measurements. Overall, 28 patients responded to the treatment (post-treatment improvement > 50% or apnea−hypopnea index (AHI) < 1/h), and 35 did not (post-treatment improvement < 50% and AHI ≥ 1/h). Significantly larger cranial base angle (SNBa), smaller lower gonial angle (LGo Angle), and shorter length of anterior cranial base (SN) were found in responders. Smaller lower gonial angle (LGo Angle) and smaller anterior cranial base (SN) predict a favorable outcome for pediatric OSAS using a tongue-beaded OA. This finding will equip practitioners with additional insights when selecting suitable candidates for OA therapy in pediatric patients.

Cardiometabolic risk profile in non-obese children with obstructive sleep apnea syndrome

Obstructive sleep apnea syndrome (OSAS) in childhood is a complex disease primarily due both to adenotonsillar hypertrophy and pediatric obesity. Notably, inflammation has been recognized as one of the most important shared pathogenic factor between obesity and OSAS resulting in an increased cardiometabolic risk for these patients. To date, evidence is still limited in non-obese population with OSAS. We aimed to evaluate the cardiometabolic risk profile of a pediatric population of non-obese subjects affected by OSAS. A total of 128 school-aged children (mean age 9.70 ± 3.43) diagnosed with OSAS and 213 non-OSAS children (mean age 9.52 ± 3.35) as control group were enrolled. All subjects underwent a complete clinical and biochemical assessment (including white blood cell count (WBC), platelet count (PLT), mean platelet volume (MPV), % of neutrophils (NEU%), C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), serum glucose, aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyl transpeptidase (GGT), uric acid, fasting insulin, iron, ferritin, and transferrin levels). A significant association between inflammation markers (including WBC, PLT, MPV, NEU%, ferritin, CPR, and ESR) and OSAS was found (all p < 0.001). Children with OSAS also showed increased transaminase, glucose, uric acid, and insulin levels (all p < 0.001) compared to healthy controls.

CONCLUSION

Taken together, these findings suggested a worse cardiometabolic profile in non-obese children with OSAS. Given the pivotal pathogenic role of inflammation both for hypoxiemia and metabolic derangements, therapeutic strategies for OSAS might also counteract the increased cardiometabolic risk of these patients, by improving their long-term quality of life.

WHAT IS KNOWN

• Pediatric OSAS has shown a close relationship with obesity and its cardiometabolic comorbidities. • Inflammation represents the hallmark of both obesity and OSAS.

WHAT IS NEW

• Non obese children with OSAS presented with a worse cardiometabolic risk profile. • OSAS treatment might serve as an effective approach also for the increased cardiometabolic risk of these children.

Expression and clinical significance of IL-33 and its receptor ST2 in children with obstructive sleep apnea syndrome

BACKGROUND

Obstructive sleep apnea syndrome (OSAS) is characterized by a majority population of respiratory sleep disorders, which consists of simple snoring as well as increased upper airway resistance syndrome. Adenoid hypertrophy has been suggested as the main cause of OSAS in children. The role of interleukin-33 (IL-33) and its receptor suppressor of tumorigenicity 2 (ST2) in a variety of pediatric allergic diseases has been confirmed. We hypothesized that IL-33/ST2 path way might play a pivotal role in the pathogenesis of adenoid hypertrophy-associated OSAS in children.

METHODS

A total of 40 children undergoing adenoidectomy due to OSAS in the Otolaryngology of Tianjin Children's Hospital were selected as the study participants. The quantity of IL-33 and ST2 positive cells in adenoids was detected by immunohistochemical (IHC) streptavidin-peroxidase conjugate (SP) method.

RESULTS

The IL-33 positive cells were mainly distributed in the submucosa epithelium and vascular endothelium, and expressed in the nucleus and cytoplasm. Meanwhile, ST2 positive cells were primarily observed in the mucosa and expressed in the nucleus and cytoplasm, with a little expression of intercellular substance. There was a positive correlation between the proportion of adenoids in the posterior nostril diameter and the number of IL-33 positive cells. The expression of IL-33 in adenoids was positively correlated with the level of ST2 (r=0.809, P=0.000). The expression of IL-33 in adenoids was positively correlated with the level of eosinophil granulocyte (r=0.859, P=0.000). Moreover, the expression of ST2 in adenoids was positively correlated with the level of eosinophil granulocyte (r=0.814, P=0.000). The number of IL-33 positive cells was significantly higher in the moderate hypoxemia group than that in the mild hypoxemia group (P<0.05). There was no significant difference in the number of ST2 positive cells between the moderate hypoxemia group and mild hypoxemia group (P>0.05).

CONCLUSIONS

Both IL-33 and its receptor ST2 were expressed in adenoids of OSAS children. The severity of airway obstruction caused by adenoid hypertrophy was positively correlated with the expression of IL-33.

Analysis of polysomnogram findings in children with concurrent obstructive and central sleep apnea

OBJECTIVE

Increasing evidence suggests overlap in mechanisms of obstructive and central sleep apnea. Our objective was to compare the patient characteristics and polysomnographic findings of children with concurrent obstructive and central sleep apnea (obstructive sleep apnea + central sleep apnea [OSA + CSA]), to those with OSA only.

METHODS

A retrospective case series of polysomnogram (PSG) from 30 June 2013 to 30 June 2018 of patients 18 years and younger was performed. PSG parameters were analyzed per standard protocol. There were two groups, OSA only group and OSA + CSA group. OSA + CSA was subdivided into groups of central apnea index (CAI) ≤5, and CAI >5. Differences in the age, sex, body mass index (BMI) percentile, prevalence of medical conditions, and PSG parameters between OSA only and OSA + CSA were assessed for statistical significance.

RESULTS

The mean age of the OSA only group was 8.2 years, significantly higher than that of the OSA + CSA group, 5.0 years, P < .00001. The proportion of underweight, normal weight, overweight, and obese patients according to BMI percentiles was not statistically significantly different between the two groups, P > .05. Most common comorbidity in the two groups was pulmonary conditions, which included asthma. Of the PSG parameters, arousals due to respiratory events and obstructive apnea hypopnea index of all OSA + CSA groups were significantly higher than those of the OSA only group, P < .05. Rapid eye movement (REM) sleep was significantly higher in total OSA + CSA group and OSA + CSA subgroup with CAI ≤5, P < .05, compared to OSA only.

CONCLUSION

Children with concurrent OSA + CSA are younger, but there appears to be no difference in BMI percentiles between OSA only and OSA + CSA. Compared to OSA only group, children with concurrent OSA + CSA have significantly different sleep architecture-higher REM %-and experience significantly higher respiratory arousals and obstructive events, especially in the subgroup with CAI >5. There appears to be overlap in mechanisms of CSA and OSA in this cohort.

LEVEL OF EVIDENCE

4.

Much Ado about Sleep: Current Concepts on Mechanisms and Predisposition to Pediatric Obstructive Sleep Apnea

Obstructive Sleep Apnea (OSA) is a form of sleep-disordered breathing characterized by upper airway collapse during sleep resulting in recurring arousals and desaturations. However, many aspects of this syndrome in children remain unclear. Understanding underlying pathogenic mechanisms of OSA is critical for the development of therapeutic strategies. In this article, we review current concepts surrounding the mechanism, pathogenesis, and predisposing factors of pediatric OSA. Specifically, we discuss the biomechanical properties of the upper airway that contribute to its primary role in OSA pathogenesis and examine the anatomical and neuromuscular factors that predispose to upper airway narrowing and collapsibility.

Successful treatment of a child with Schwartz-Jampel syndrome using rapid maxillary expansion and CPAP

STUDY OBJECTIVES

We reported an 8-year-old male patient with Schwartz-Jampel syndrome, severe obstructive sleep apnea, constricted maxilla and moderate tonsillar hypertrophy. The syndrome is characterized by myotonia, skeletal dysplasia, and facial dysmorphism.

METHODS

CPAP was initially prescribed, but he was not able to tolerate due to a high pressure setting. Rapid maxillary expansion alone reduced AHI to 10.4 events/h.

RESULTS

When combined with CPAP, AHI is further reduced to 2.4 events/h. The patient has a better compliance with CPAP following rapid maxillary expansion therapy as the pressure setting decreased.

CONCLUSIONS

This is the first report utilizing a combination of rapid maxillary expansion and CPAP therapy to successfully treat severe pediatric OSA.

Obstructive sleep apnea and fractures in children and adolescents

STUDY OBJECTIVES

To examine, among girls and boys, associations between site-specific extremity fracture and sleep apnea diagnosis or treatment.

METHODS

A cross-sectional analysis of claims data from 2016-2018 for children aged 2-18. Children with sleep apnea, continuous positive airway pressure, adenotonsillectomy, and fracture were identified using ICD10, CPT and HCPCS codes. We examined sex-stratified associations between site-specific fracture, sleep apnea and sleep apnea treatment.

RESULTS

Among 2,327,104 children, 9,547 (0.41%) had sleep apnea and nearly 61% were treated. Girls with sleep apnea, treated or untreated, had increased odds of lower, but not upper, extremity fracture compared to those without sleep apnea (treated 1.56, 95% CI 1.11, 2.21; untreated OR 1.63, 95% CI 1.09, 2.44). Only boys untreated for sleep apnea had increased odds of lower extremity fracture in comparison to those without a diagnosis of sleep apnea (OR 1.65, 95% CI 1.20,2.27). Interestingly, boys treated for sleep apnea but not those untreated, in comparison to boys without sleep apnea, had different (reduced) odds of upper extremity fracture (OR 0.74, 95% CI 0.59, 0.95).

CONCLUSIONS

These large datasets provide evidence that both boys and girls with untreated sleep apnea have higher odds of lower extremity fractures. However, treatment for sleep apnea was associated with improved odds of lower extremity fracture only in boys. Upper extremity data were less clear. These data are cross-sectional and cannot show causality, but they suggest that treatment for sleep apnea may lower risk for extremity fractures in boys.

Efficacy of a Pediatric Sleep Questionnaire for the Diagnosis of Obstructive Sleep Apnea in Children

Background: Obstructive sleep apnea (OSA) is a source of significant morbidity in children. Polysomnography (PSG), the gold standard diagnostic tool for OSA, is often unavailable due to patient financial and geographic constraints. Our objective is to analyze the relationship between a patient's subjective complaints and the results from their PSG to determine the diagnostic value of the Pediatric Sleep Questionnaire (PSQ) for detecting OSA in children.

Methods: A retrospective chart review was conducted for pediatric patients with suspected OSA from March 2012 to January 2014. Preoperative PSQ scores were compared with the results from PSG in the form of Apnea-Hypopnea Index (AHI) and Respiratory Disturbance Index (RDI) values. AHI and RDI values ranging from 1 to 5 were classified as mild OSA while values ranging from 5 to 10 were classified as moderate OSA.

Results: A total of 161 patients were recruited for this study with 63 patients (39%) both completing the PSQ and undergoing PSG. Sensitivity of the positive questionnaire was higher in patients with AHI and RDI values indicative of moderate OSA (95% and 100% respectively) versus values indicative of mild OSA (83% and 86% respectively). Conversely, the positive predictive value of the positive questionnaire (n=49) was lower in patients with AHI and RDI values indicative of moderate OSA (39% and 46% respectively) versus values indicative of mild OSA (70% and 80% respectively).

Conclusion: The PSQ has high diagnostic value for screening patients with suspected OSA. We recommend the use of the PSQ in the primary care setting for children with suspected OSA.

Proteomic Study Identifies Glycolytic and Inflammation Pathways Involved in Recurrent Otitis Media

Recurrent acute otitis media (RAOM) in children is clinically defined as the occurrence of at least three episodes of acute otitis media over a course of 6 months. A further common pathological condition of interest in the context of pediatric otolaryngology is adenotonsillar hypertrophy (ATH), a common cause of obstructive sleep apnea syndrome. Aimed at unraveling the differential modulation of proteins in the two pathologies and at understanding the possible pathways involved in their onset, we analyzed the proteomic profile of the adenoids from 14 RAOM and ATH patients by using two-dimensional gel electrophoresis (2-DE) and mass spectrometry (MS). The 2-DE coupled with MS allowed us to identify 23 spots with significant (p-value < 0.05) changes in protein amount, recognizing proteins involved in neutrophil degranulation and glycolysis pathways.

Predictive equation for optimal continuous positive airway pressure in children with obstructive sleep apnoea

Aim

A subgroup of children with obstructive sleep apnoea (OSA) requires treatment with continuous positive airway pressure (CPAP). This study's aims were: 1) to determine if the optimal CPAP for the treatment of OSA in children correlates with body mass index (BMI); 2) to determine the correlation between polysomnographic variables and optimal CPAP in children with OSA; and 3) to develop a CPAP predictive equation for children with OSA.

Methods

This was a retrospective study of children with OSA who underwent CPAP titration studies. Patients with craniofacial abnormalities (except Down syndrome) and neuromuscular diseases were excluded. Polysomnograms were done using Sandman Elite. Correlations between optimal CPAP, clinical and polysomnographic variables were analysed. A multivariable linear regression model for optimal CPAP was developed.

Results

198 children (mean±sd age 13.1±3.6 years) were studied. Optimal CPAP had a significant positive correlation with age (rho=0.216, p=0.002), obstructive apnoea-hypopnoea index (rho=0.421, p<0.001), 3% oxygen desaturation index (rho=0.417, p<0.001), rapid eye movement respiratory disturbance index (rho=0.378, p<0.001) and BMI z-score (rho=0.160, p=0.024); and a significant negative correlation with arterial oxygen saturation measured by pulse oximetry nadir (rho= −0.333, p<0.001). The predictive equation derived was:

Optimal CPAP (cmH₂O)=6.486+0.273·age (years)−0.664·adenotonsillectomy

(no=1, yes=0)+2.120·Down syndrome (yes=1, no=0)+0.280·BMI z-score.

Conclusion

The equation developed may help to predict optimal CPAP in children with OSA. Further studies are required to validate this equation and to determine its applicability in different populations.

A predictive equation may help derive the optimal CPAP for the treatment of obstructive sleep apnoea in childrenhttp://bit.ly/2wTf6Bw

Polysonographical evaluation in a case of moderate osas treated with mandibular advancement device

Background

The Obstructive Sleep Apnea Syndrome (OSAS) is a clinical picture characterized by partial or complete obstruction of the upper airway during sleep, associated with a reduction of oxygen saturation in the blood.The most common symptoms are: apnea sleep, snoring, headache, sleepiness, reduced concentration and memory, irritability, increased blood pressure and dry mouth.

Materials and methods

It was examinated a not-smoker man of 54 years that suffers of roncophaty. He did physical examination, rhinoscopyexam, faringoscopy, rhinofibrolaringoscopy, gnathological evaluation and polysomnographic examination performed with multichannel polygraphy (VitalNight). From the performed examinations, it has been diagnosed a moderate form of obstructive apnea sleep syndrome. He was treated with a mandibular advancement device and it was repeated the polysomnographic exam.

Results

Comparing the results of the polysonographic examination performed before and after the treatment, the patient's clinical picture clearly improved. It has shown a clear reduction of obstructive apneas, hypopneas and snoring.

Conclusions

The use of a mandibular advancement device is certainly a valuable aid in the treatment of moderate type OSAS. The quality of diurnal life is also improved as shown with Sleepness Epworth Scale.