Snoring and obstructive sleep apnoea in children: why should we treat?

Virus as Teratogenic Agents

Viral infectious diseases are important causes of reproductive disorders, as abortion, fetal mummification, embryonic mortality, stillbirth, and congenital abnormalities in animals and in humans. In this chapter, we provide an overview of some virus, as important agents in teratology.We begin by describing the Zika virus, whose infection in humans had a very significant impact in recent years and has been associated with major health problems worldwide. This virus is a teratogenic agent in humans and has been classified as a public health emergency of international concern (PHEIC).Then, some viruses associated with reproductive abnormalities on animals, which have a significant economic impact on livestock, are described, as bovine herpesvirus, bovine viral diarrhea virus, Schmallenberg virus, Akabane virus, and Aino virus.For all viruses mentioned in this chapter, the teratogenic effects and the congenital malformations associated with fetus and newborn are described, according to the most recent scientific publications.

Diagnosis and Treatment of Sleep Apnea in Children: A Future Perspective Is Needed

Obstructive sleep apnea (OSA) in children is a prevalent, but still, today, underdiagnosed illness, which consists of repetitive episodes of upper airway obstruction during sleep with important repercussions for sleep quality. OSA has relevant consequences in the pediatric population, mainly in the metabolic, cardiovascular (CV), and neurological spheres. However, contrary to adults, advances in diagnostic and therapeutic management have been scarce in the last few years despite the increasing scientific evidence of the deleterious consequences of pediatric OSA. The problem of underdiagnosis and the lack of response to treatment in some groups make an update to the management of OSA in children necessary. Probably, the heterogeneity of OSA is not well represented by the classical clinical presentation and severity parameters (apnea/hypopnea index (AHI)), and new strategies are required. A specific and consensus definition should be established. Additionally, the role of simplified methods in the diagnosis algorithm should be considered. Finally, the search for new biomarkers for risk stratification is needed in this population. In conclusion, new paradigms based on personalized medicine should be implemented in this population.

Sleep-disordered breathing in children seeking orthodontic care-an Australian perspective

BACKGROUND

The prevalence of sleep-disordered breathing in children is underestimated due to impediments in detection and diagnosis. Consequently, delayed management may affect the quality of life and the growth and development of a child. Due to their patient demographic, orthodontists are optimally positioned to identify those at risk of sleep-disordered breathing and make referrals for investigation and management. This study aims to determine the prevalence of children at risk of sleep-disordered breathing in an Australian orthodontic population.

METHODS

A 1-year retrospective study was conducted in an urban Western Australian private orthodontic practice with two branches in similar socioeconomic demographics. The responses of new patients to a modified paediatric sleep questionnaire and standard medical history form were recorded.

RESULTS

In 1209 patients (4-18 years), 7.3% were at risk of sleep-disordered breathing. An association between sex and the potential risk of sleep-disordered breathing was found with 11% of males at risk of sleep-disordered breathing compared to 7% of females (P = 0.012).

CONCLUSIONS

The relatively high prevalence of children at risk of sleep-disordered breathing presenting for orthodontic care presents an opportunity to identify at-risk individuals through routine use of the paediatric sleep questionnaire. This would facilitate early referral for diagnosis and management of sleep-disordered breathing.

Association of orofacial dysfunction and sleep disordered breathing among Indian primary school children

Introduction

Sleep-disordered breathing (SDB) ranges from partial obstruction of the upper airway resulting in snoring to total upper airway obstruction leading to obstructive sleep apnea. The impairment in the dynamics of the stomatognathic system is termed as orofacial dysfunction. This study investigates the prevalence of orofacial dysfunction and sleep-disordered breathing in primary school children and identifies their correlation.

Methods

A total of 560 forms were distributed to 8 primary schools in Belagavi city. Among them, 482 parents responded (86% response rate), which included 239 boys (49.58%) and 243 girls (50.41%). All the participants were screened for orofacial dysfunction using Nordic Orofacial Dysfunction Test-screening (NOT-S) and sleep-disordered breathing using the Pediatric Sleep Questionnaire (PSQ).

Result

A positive direct correlation of sleep-disordered breathing with orofacial dysfunction (r = 0.47; p ≤ 0.001) was noted. A total of 41(8.58%) children were found to be at risk of sleep-disordered breathing with a score less than or equal to eight, based on (PSQ) Pediatric Sleep Questionnaire, and 156 (32.6%) children showed symptoms of orofacial dysfunction based on Nordic Orofacial Test-Screening (NOT-S).

Conclusion

The study demonstrates that around 32.6% of children had orofacial dysfunction symptoms, and 8.58% of children were at risk for sleep-disordered breathing, girls having a greater risk as compared to boys. There was a positive correlation between orofacial dysfunction and sleep-disordered breathing among children aged 6-12 years.

Comparison of airway pressures and expired gas washout for nasal high flow versus CPAP in child airway replicas

Background

For children and adults, the standard treatment for obstructive sleep apnea is the delivery of continuous positive airway pressure (CPAP). Though effective, CPAP masks can be uncomfortable to patients, contributing to adherence concerns. Recently, nasal high flow (NHF) therapy has been investigated as an alternative, especially in CPAP-intolerant children. The present study aimed to compare and contrast the positive airway pressures and expired gas washout generated by NHF versus CPAP in child nasal airway replicas.

Methods

NHF therapy was investigated at a flow rate of 20 L/min and compared to CPAP at 5 cmH₂O and 10 cmH₂O for 10 nasal airway replicas, built from computed tomography scans of children aged 4–8 years. NHF was delivered with three different high flow nasal cannula models provided by the same manufacturer, and CPAP was delivered with a sealed nasal mask. Tidal breathing through each replica was imposed using a lung simulator, and airway pressure at the trachea was recorded over time. For expired gas washout measurements, carbon dioxide was injected at the lung simulator, and end-tidal carbon dioxide (EtCO₂) was measured at the trachea. Changes in EtCO₂ compared to baseline values (no intervention) were assessed.

Results

NHF therapy generated an average positive end-expiratory pressure (PEEP) of 5.17 ± 2.09 cmH₂O (mean ± SD, n = 10), similar to PEEP of 4.95 ± 0.03 cmH₂O generated by nominally 5 cmH₂O CPAP. Variation in tracheal pressure was higher between airway replicas for NHF compared to CPAP. EtCO₂ decreased from baseline during administration of NHF, whereas it increased during CPAP. No statistical difference in tracheal pressure nor EtCO₂ was found between the three high flow nasal cannulas.

Conclusion

In child airway replicas, NHF at 20 L/min generated average PEEP similar to CPAP at 5 cm H₂O. Variation in tracheal pressure was higher between airway replicas for NHF than for CPAP. The delivery of NHF yielded expired gas washout, whereas CPAP impeded expired gas washout due to the increased dead space of the sealed mask.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12931-021-01880-z.

The Relationship Between Obstructive Sleep Apnea and Pediatric Obesity: A Nationwide Analysis

OBJECTIVE

Pediatric obstructive sleep apnea (OSA) can have both acute and chronic consequences when untreated. We hypothesize that a link exists between childhood obesity and OSA at nationwide level, with race, gender, and socioeconomic status conferring their own risk for pediatric OSA.

METHODS

This study examined nationwide discharges in 2016 using the Kids' Inpatient Database (KID). The International Classification of Diseases, 10th revision, Clinical Modification (ICD-10-CM) codes for obesity (E66.0) and OSA (G47.33) were used. Prevalence rates and odds ratios (ORs) were used to quantify associations between the obesity and OSA groups in the general pediatric inpatient population. Multiple binary logistic regression was utilized to compare cohorts of pediatric inpatient admissions.

RESULTS

There were 36 266 285 weighted discharges in the 2016 KID. Among patients included in our dataset, 0.426% (26 684) were diagnosed with obesity and 0.562% (35 242) had OSA. Obesity was independently associated with a significantly increased risk of OSA (OR = 22.89; 95% C.I. = 21.99-23.84). Within the OSA inpatient population, obesity was associated with non-Hispanic black race, Hispanic ethnicity, and Native American race/ethnicity (OR = 1.45, 1.32, 2.51; 95% C.I. = 1.33-1.58, 1.21-1.44, 1.73-3.63).

CONCLUSIONS

Obesity is independently associated with OSA in children after controlling for adenotonsillar hypertrophy. Non-Hispanic black race and Hispanic ethnicity are independent risk factors for OSA and are associated with obesity in the OSA inpatient population, which suggests that obesity may play a role in the increased risk of OSA within these groups.

Screening Severe Obstructive Sleep Apnea in Children with Snoring

Efficient screening for severe obstructive sleep apnea (OSA) is important for children with snoring before time-consuming standard polysomnography. This retrospective cross-sectional study aimed to compare clinical variables, home snoring sound analysis, and home sleep pulse oximetry on their predictive performance in screening severe OSA among children who habitually snored. Study 1 included 9 (23%) girls and 30 (77%) boys (median age of 9 years). Using univariate logistic regression models, 3% oxygen desaturation index (ODI3) ≥ 6.0 events/h, adenoidal-nasopharyngeal ratio (ANR) ≥ 0.78, tonsil size = 4, and snoring sound energy of 801–1000 Hz ≥ 22.0 dB significantly predicted severe OSA in descending order of odds ratio. Multivariate analysis showed that ODI3 ≥ 6.0 events/h independently predicted severe pediatric OSA. Among several predictive models, the combination of ODI3, tonsil size, and ANR more optimally screened for severe OSA with a sensitivity of 91% and a specificity of 94%. In Study 2 (27 (27%) girls and 73 (73%) boys; median age, 7 years), this model was externally validated to predict severe OSA with an accuracy of 76%. Our results suggested that home sleep pulse oximetry, combined with ANR, can screen for severe OSA more optimally than ANR and tonsil size among children with snoring.

The Prevalence of Adenoid Hypertrophy among Children with Zika Related Microcephaly

Upper respiratory obstruction is a common sequela in children with Zika-related microcephaly (ZRM). As a cross-sectional analysis nested in a cohort study, this study aims to investigate the prevalence of adenoid hypertrophy (AH) in children with ZRM and symptoms of respiratory obstruction. The data were collected in the first three years of life from children with ZRM who were followed in two reference centers for otorhinolaryngological care of patients with congenital Zika syndrome. Out of 92 children with confirmed ZRM, 57 were evaluated by nasopharyngoscopy after presenting with upper respiratory obstruction symptoms. In this study, 31 of the 57 (54%) children with ZRM who were evaluated had obstructive AH. Thirteen children with obstructive AH were submitted to surgery, which resulted in the complete resolution of symptoms for 11, partial resolution in 1, and no improvement in 1. No evidence of direct involvement by Zika virus (ZIKV) infection in the adenoid tissues was demonstrated by histology or immunohistochemistry. Our results suggest that there is a high prevalence and early presentation of AH in children with ZRM, with consequent upper airway obstruction causing upper airway obstructive disorder, secretory otitis media, and dysphagia.

Prevalence of Pulmonary Hypertension in Pediatric Patients With Obstructive Sleep Apnea and a Cardiology Evaluation: A Retrospective Analysis

STUDY OBJECTIVES

Pulmonary hypertension (PH) has been reported as a serious complication of obstructive sleep apnea (OSA) in children; however, estimated prevalence rates vary widely (zero to 85%). The purpose of this study is to determine the prevalence of PH in children with OSA and identify factors that may predict an increased PH risk in children with OSA.

METHODS

A retrospective review of all pediatric beneficiaries (88,058) in the San Antonio Military Health System with a diagnosis of OSA and a clinical evaluation by a pediatric cardiologist. OSA severity and nadir oxygen saturation were recorded from overnight polysomnography. Reason for referral, comorbid disorders, echocardiogram results, and cardiac diagnoses were obtained from cardiology records.

RESULTS

OSA was identified in 2,020 pediatric patients (2.3%). A pediatric cardiology consultation was reported for 296 patients with OSA. After excluding 95 patients for incorrect OSA diagnoses, incomplete data, or OSA treatment before cardiology evaluation, 163 patients were included in the final analysis. A diagnosis of PH was found in 3 patients with OSA (1.8%). Two of these patients had obesity, and all three had comorbid cardiac disorders.

CONCLUSIONS

Prevalence of PH in pediatric patients with OSA is low and none of the patients with PH had severe OSA. Current guidelines recommend PH screening in patients with severe OSA, yet OSA severity may not accurately predict risk. Factors evaluated in this study did not demonstrate an increased PH risk; additional research is necessary to improve screening in pediatric patients with OSA.

CITATION

Burns AT, Hansen SL, Turner ZS, Aden JK, Black AB, Hsu DP. Prevalence of pulmonary hypertension in pediatric patients with obstructive sleep apnea and a cardiology evaluation: a retrospective analysis. J Clin Sleep Med. 2019;15(8):1081-1087.

Tobacco smoke exposure as a risk factor for obstructive sleep apnea in children

BACKGROUND

The most common respiratory disturbance in sleeping children is obstructive sleep apnea syndrome (OSAS). Passive smoking is one of factors predisposing to OSAS. The aim of this study was to determine the correlations between exposure to tobacco smoke (passive smoking) and development of respiratory disorders in children during sleep.

METHODS

One hundred and sixty school-aged children (6-18 years) were included in the study. The inclusion criterion was exposure to tobacco smoke at home (n = 90). The control group were school-aged children who had had no contact with tobacco smoke at home (n = 70). Exclusion criteria were obesity and children with impaired patency of the nose. Each child had a polygraphic examination performed at home. The children and their parents completed a questionnaire to assess the level of child's exposure to tobacco smoke. The study ran from December 15, 2012 to February 26, 2016.

RESULTS

OSAS was observed in 12% of children with an apnea-hypopnea index >1.5 (<13 years of age) and an apnea-hypopnea index >5 (for children >13 years), and with diurnal and nocturnal symptoms. Children exposed to tobacco smoke presented more apnea-hypopnea events (n = 17) than the control group (n = 3; P < 0.001). In the group exposed to tobacco smoke the following issues were noted: concentration problems (38.9%), tiredness/lethargy (46.7%), and irritability/hyperactivity (36.7%). No statistically significant differences were found in waking up, snoring, or sleep apnea.

CONCLUSIONS

OSAS occurs more often in children exposed to tobacco smoke and these children demonstrate concentration problems, tiredness, and irritability/hyperactivity to a greater extent than control group.

Cognitive Effects of Adenotonsillectomy for Obstructive Sleep Apnea

OBJECTIVE

Research reveals mixed evidence for the effects of adenotonsillectomy (AT) on cognitive tests in children with obstructive sleep apnea syndrome (OSAS). The primary aim of the study was to investigate effects of AT on cognitive test scores in the randomized Childhood Adenotonsillectomy Trial.

METHODS

Children ages 5 to 9 years with OSAS without prolonged oxyhemoglobin desaturation were randomly assigned to watchful waiting with supportive care (n = 227) or early AT (eAT, n = 226). Neuropsychological tests were administered before the intervention and 7 months after the intervention. Mixed model analysis compared the groups on changes in test scores across follow-up, and regression analysis examined associations of these changes in the eAT group with changes in sleep measures.

RESULTS

Mean test scores were within the average range for both groups. Scores improved significantly (P < .05) more across follow-up for the eAT group than for the watchful waiting group. These differences were found only on measures of nonverbal reasoning, fine motor skills, and selective attention and had small effects sizes (Cohen's d, 0.20-0.24). As additional evidence for AT-related effects on scores, gains in test scores for the eAT group were associated with improvements in sleep measures.

CONCLUSIONS

Small and selective effects of AT were observed on cognitive tests in children with OSAS without prolonged desaturation. Relative to evidence from Childhood Adenotonsillectomy Trial for larger effects of surgery on sleep, behavior, and quality of life, AT may have limited benefits in reversing any cognitive effects of OSAS, or these benefits may require more extended follow-up to become manifest.

Declarative and Non-declarative Memory Consolidation in Children with Sleep Disorder

Healthy sleep is essential in children’s cognitive, behavioral, and emotional development. However, remarkably little is known about the influence of sleep disorders on different memory processes in childhood. Such data could give us a deeper insight into the effect of sleep on the developing brain and memory functions and how the relationship between sleep and memory changes from childhood to adulthood. In the present study we examined the effect of sleep disorder on declarative and non-declarative memory consolidation by testing children with sleep-disordered breathing (SDB) which is characterized by disrupted sleep structure. We used a story recall task to measure declarative memory and Alternating Serial Reaction time (ASRT) task to assess non-declarative memory. This task enables us to measure two aspects of non-declarative memory, namely general motor skill learning and sequence-specific learning. There were two sessions: a learning phase and a testing phase, separated by a 12 h offline period with sleep. Our data showed that children with SDB exhibited a generally lower declarative memory performance both in the learning and testing phase; however, both the SDB and control groups exhibited retention of the previously recalled items after the offline period. Here we showed intact non-declarative consolidation in SDB group in both sequence-specific and general motor skill. These findings suggest that sleep disorders in childhood have a differential effect on different memory processes (online vs. offline) and give us insight into how sleep disturbances affects developing brain.

Polysomnographic Markers in Children With Cystic Fibrosis Lung Disease

BACKGROUND AND OBJECTIVES

Children with cystic fibrosis (CF) often report poor sleep, increased daytime sleepiness, and fatigue. The purpose of this study was to identify respiratory patterns over the spectrum of disease severity in children with CF. The overall hypothesis for the current study is that children with CF compared with snoring control subjects demonstrate gas exchange abnormalities and increased respiratory loads during sleep that are not reported or recognized by conventional polysomnography (PSG).

METHODS

Analysis of breathing patterns and gas exchange on PSG was performed in children with CF and healthy controls matched by age and BMI. For all CF and control subjects, the indication for PSG was evaluation for obstructive sleep apnea based on a history of snoring.

RESULTS

Children with CF, compared with age- and BMI-matched snoring controls, demonstrated lower oxyhemoglobin saturation (95% ± 1.6% vs 98% ± 0.6%, P = .005), higher respiratory rate (19.5 ± 4.9 vs 16.5 ± 1.2 breaths per minute, P = .03), and a higher proportion of inspiratory flow limitation (44.1% ± 24.7% vs 12.1% ± 13.5%, P = .007) during non-rapid eye movement sleep. The respiratory disturbance index did not differ between CF and snoring control groups (1.5 ± 2.7 vs 0.6 ± 0.6 events per hour, P = .11).

CONCLUSIONS

Children with CF exhibited abnormalities in gas exchange and increased respiratory load during sleep compared with normal age- and BMI-matched snoring controls. Because these abnormalities were independent of weight and lung function, sleep state may serve as an opportunity for early detection of breathing abnormalities and possibly CF lung disease progression.

Influence of Orthodontic Rapid Maxillary Expansion on Nocturnal Enuresis in Children

BACKGROUND

The etiology of nocturnal enuresis (NE) is multifactorial and has not been fully explained yet. New ways of treatment are constantly being investigated, including the rapid maxillary expansion (RME).

METHODS

A total of 41 patients diagnosed with NE were divided into two experimental groups: A and B. Group A included 16 children who have been treated with RME. Group B comprised 25 children who have not undertaken orthodontic treatment. Children from both groups have been monitored in monthly intervals, during a 12-month period, towards the intensification of NE. The comparative analysis of both groups has been conducted after 3 years of observation.

RESULTS

Statistical analysis has shown a 4.5 times increase of the probability of reduction of NE in the case of the treated group in comparison with the group of children who have not undergone orthodontic treatment. Unfortunately, the chance of obtaining total dryness diminished proportionally to the higher degree of intensification of enuresis at the beginning of the test.

CONCLUSION

RME can constitute an alternative method of NE treatment in children, irrespective of the occurrence of upper jaw narrowing.

Inflammation and growth in young children with obstructive sleep apnea syndrome before and after adenotonsillectomy

Background. Obstructive sleep apnea (OSA) is associated with growth impairment that usually improves following effective treatment. In this study we investigated the mechanisms underlying the growth processes in young children diagnosed with OSA, before and after adenotonsillectomy (T&A). Methods. Young children (6–36 months old) were enrolled and evaluated before and several months after T&A surgery for height, weight, circulating high sensitive C-reactive protein (CRP), and insulin-like growth factor 1 (IGF-1) levels. Caloric intake was assessed by a validated Short Food Frequency Questionnaire (SFFQ). Results. Following T&A, children added 4.81 cm and 1.88 kg to their height and weight, respectively (P < 0.001 for both) and had a significant increase in BMI Z score (P = 0.002). Increased caloric intake of 377 kcal/day was noted (P < 0.001), with increased protein and decreased fat intake. The decrease in CRP levels correlated with the increase in body weight in boys (P < 0.05, adjusted for caloric intake). Conclusions. Adenotonsillectomy results in enhanced somatic growth in young children that correlates with a decrease in systemic inflammation and caloric intake increment. Our findings imply that systemic inflammation may have an important role in this OSA-related morbidity.

Saudi Guidelines on the Diagnosis and Treatment of Pulmonary Hypertension: Pulmonary hypertension in children

Pulmonary hypertension (PH) is relatively uncommon in children. Pulmonary arterial hypertension (PAH) in pediatric comprises a wide spectrum of diseases, from a transient neonatal condition to a progressive disease associated with morbidity and mortality. Most common PAH in pediatric are idiopathic (IPAH) or PAH associated with congenital heart disease (PAH-CHD), while other associated conditions, such as connective tissue disease (CTD), are less common in pediatrics. Despite better understanding of PH and the availability of new medications during recent decades; the diagnosis, investigation and choice of therapy remain a challenge in children, as evidence-based recommendations depend mainly on adult studies. In this review, we provide a detailed discussion about the distinctive features of PAH in pediatric, mainly emphacysing on classification and diagnostic algorithm.

Sleep disorder in childhood impairs declarative but not nondeclarative forms of learning

A large amount of studies have investigated the association between sleep and memory systems. However, remarkably little is known of the effect of sleep disorders on declarative and nondeclarative memory for children. In the present study we examined the effects of sleep disorders on different aspects of memory functions by testing children with sleep-disordered breathing (SDB), which is characterized by disrupted sleep patterns. We used "The War of the Ghosts" test to measure declarative memory and the Alternating Serial Reaction Time (ASRT) task. This enabled us to measure two aspects of nondeclarative memory--general skill learning and sequence-specific learning--separately. Ten children with SDB and 10 healthy controls participated in this study. Our data showed dissociation between declarative and nondeclarative memory in children with SDB. They showed impaired declarative memory, while the sequence-specific and general skill learning was similar to that of healthy controls, in spite of sleep disruption. Our findings suggest that sleep-disordered breathing affects declarative and nondeclarative memory differently in children. Moreover, these findings imply that the disrupted sleep pattern influences the more attention-demanding and cortical structure-guided explicit processes, while the less attention-demanding implicit processes mediated by subcortical structures are preserved.

Upper airway changes in Pierre Robin sequence from childhood to adulthood

OBJECTIVES

To investigate pharyngeal airway changes in patients with Pierre Robin sequence (PRS) longitudinally from childhood to adulthood.

SETTING AND SAMPLE POPULATION

Cleft Lip and Palate Unit, Clinic of Orthodontics, University of Zurich. Twenty-four patients born between 1970 and 1990 with non-syndromic PRS.

MATERIALS AND METHODS

Lateral cephalograms at age 5 (T1), 10 (T2), 15 (T3) and 20 (T4) years were available. Variables describing pharyngeal airway dimensions, soft palate morphology, tongue and hyoid position, skeletal morphology and head posture were assessed.

RESULTS

A significant increase in nasopharyngeal depth was found over the entire observation period (T1 10.7 to T4 19.1 mm, p < 0.001), especially between T2 and T3 (change 3.8 mm, p < 0.001), and was mainly due to adenoid recession (r = -0.75, p < 0.001; variation explained by 56%). Increase in velopharyngeal depth mainly took place between T3 and T4 (change 2.3 mm, p < 0.01). It was due to more anterior tongue posture (r = 0.65, p < 0.001; 42.5% of variation explained), in turn allowing the soft palate to take a more vertical position (r = -0.52, p < 0.001). Increase in oropharyngeal depth was associated with head extension and anterior mandibular positioning (36% of variation explained). However, significance was not reached (T1 8.3 to T4 9.8 mm, p > 0.05).

CONCLUSIONS

Upper airway dimensions in children with PRS improve with time, except for the oropharyngeal airway. Despite large interindividual variation, the mean remained in the lower reaches of normality described in other studies. Thus, further research should investigate the prevalence of obstructive sleep apnoea in adults with PRS.

Association between primary nocturnal enuresis and habitual snoring in children with obstructive sleep apnoea-hypopnoea syndrome

INTRODUCTION

Nocturnal enuresis (NE) and obstructive sleep apnoea-hypopnoea syndrome (OSAHS) are common problems during childhood, and population studies have reported a significant correlation between them. This study aimed to assess whether habitual snoring, mouth breathing and daytime sleepiness are associated with increased incidence of NE in children with OSAHS.

MATERIAL AND METHODS

Polysomnography was performed in 42 children (66.7% males), 3.5-14.5 years old, who were evaluated for sleep-disordered breathing (SDB).

RESULTS

Fourteen out of 42 children (33.3%) presented mild, 16 out of 42 (38.1%) moderate and 12 out of 42 (28.6%) severe degree of OSAHS. Apnea hypopnea index (AHI) ranged between 1.30-94.20 (10.54 ±15.67) events per hour of sleep. Nocturnal enuresis was reported in 7/42 (16.7%) of them. The main observed symptoms were snoring (90.5%), restless sleep (81%), mouth breathing (71.4%), nasal congestion (76.2%), and difficulty in arousal (52.4%). A statistically significant association was found between NE and mouth breathing (p = 0.014) or nasal congestion (p = 0.005). Children with OSAHS and NE had a higher arousal index (8.14 ±8.05) compared with OSAHS children without NE (4.61 ±7.95) (p = 0.19, z = -1.28). Snorers had higher levels of AHI (11.02 ±16.37) compared with non-snorers (6.05 ±4.81) (p = 0.33, z = -0.96), and habitually snorers (23/42, 54.76%) were at greater risk of having NE (4/23) than were non-snorers (0/4, p = 0.36). However, the prevalence of enuresis was not related to the severity of OSAHS, expressed as AHI (p = 0.70).

CONCLUSIONS

Mouth breathing, nasal congestion and high threshold of arousal during sleep should be more carefully evaluated in cases of children with NE who do not respond to standard treatment and present SDB.

Prevalence and Severity of Obstructive Sleep Apnea and Snoring in Infants with Pierre Robin Sequence

Objective

To evaluate the prevalence and severity of obstructive sleep apnea in infants with Pierre Robin sequence prior to airway intervention and determine whether snoring correlates with the presence of obstructive sleep apnea in this population.

Design

Retrospective case series.

Setting

Urban tertiary care teaching hospital.

Participants/Methods

Review of infants with Pierre Robin sequence who underwent polysomnography in the first year of life from 2002 to 2007. Only results from the initial polysomnography were analyzed. A subgroup of consecutive prospectively tested patients was also evaluated.

Results

A total of 33 infants with Pierre Robin sequence were identified. Of these, 13 (39%), 11 girls and two boys, underwent polysomnography in the first year of life. The mean age at evaluation was 48 days (range, 7 to 214 days). Seven nonconsecutive and six consecutive patients were included, and no significant differences were seen between groups. Obstructive sleep apnea was identified in 11 of 13 (85%) infants. The mean obstructive apnea-hypopnea index was 33.5 (range, 0 to 85.7). Obstructive sleep apnea severity was mild in 2 of 11 (18%), moderate in 3 of 11 (27%), and severe in 6 of 11 (55%). Mean end-tidal Pco2 measurements were elevated at 59 mm Hg (range, 47 to 76 mm Hg). Mean oxygen saturation nadir was decreased at 80% (range, 68% to 93%). Snoring occurred in only 7 of 13 (54%). Of the subjects with obstructive sleep apnea, snoring occurred in 6 of 11 (55%).

Conclusion

The high incidence of obstructive sleep apnea in this group suggests that polysomnography should be promptly performed in children with Pierre Robin sequence. Although snoring was seen in the majority, the absence of snoring did not exclude the presence of obstructive sleep apnea.

Obstructive sleep apnea syndrome: from phenotype to genetic basis

Obstructive sleep apnea syndrome (OSAS) is a complex chronic clinical syndrome, characterized by snoring, periodic apnea, hypoxemia during sleep, and daytime hypersomnolence. It affects 4-5% of the general population. Racial studies and chromosomal mapping, familial studies and twin studies have provided evidence for the possible link between the OSAS and genetic factors and also most of the risk factors involved in the pathogenesis of OSAS are largely genetically determined. A percentage of 35-40% of its variance can be attributed to genetic factors. It is likely that genetic factors associated with craniofacial structure, body fat distribution and neural control of the upper airway muscles interact to produce the OSAS phenotype. Although the role of specific genes that influence the development of OSAS has not yet been identified, current researches, especially in animal model, suggest that several genetic systems may be important. In this chapter, we will first define the OSAS phenotype, the pathogenesis and the risk factors involved in the OSAS that may be inherited, then, we will review the current progress in the genetics of OSAS and suggest a few future perspectives in the development of therapeutic agents for this complex disease entity.

Obstructive sleep apnea syndrome and fatty liver: Association or causal link?

Obstructive sleep apnea (OSA) is a complex disorder that consists of upper airway obstruction, chronic intermittent hypoxia and sleep fragmentation. OSA is well known to be associated with hypoxia, insulin resistance and glucose intolerance, and these factors can occur in the presence or absence of obesity and metabolic syndrome. Although it is well established that insulin resistance, glucose intolerance and obesity occur frequently with non-alcoholic fatty liver disease (NAFLD), it is now becoming apparent that hypoxia might also be important in the development of NAFLD, and it is recognized that there is increased risk of NAFLD with OSA. This review discusses the association between OSA, NAFLD and cardiovascular disease, and describes the potential role of hypoxia in the development of NAFLD with OSA.

Phonological development in children with obstructive sleep-disordered breathing

Adeno-tonsillar hypertrophy with obstructive sleep disordered breathing (OSDB) is known to affect oral-motor function, behaviour, and academic performance. Adeno-tonsillectomy is the most frequently performed operation in children, with total tonsillectomy (TE) being more common than partial resection, 'tonsillotomy' (TT). In the present study 67 children, aged 50-65 months, with OSBD were randomized to TE or TT. The children's phonology was assessed pre-operatively and 6 months post-operatively. Two groups of children served as controls. Phonology was affected in 62.7% of OSBD children before surgery, compared to 34% in the control group (p < .001). Also, OSBD children had more severe phonological deficits than the controls (p < .001). Phonology improved 6 months equally after both surgeries. Despite improvement post-operatively, the gap to the controls increased. Other functional aspects, such as oral motor function, were normalized regardless of surgical method--TE or TT. The impact of OSBD should be considered as one contributing factor in phonological impairment.

Reactive oxygen species and respiratory plasticity following intermittent hypoxia

The neural network controlling breathing exhibits plasticity in response to environmental or physiological challenges. For example, while hypoxia initiates rapid and robust increases in respiratory motor output to defend against hypoxemia, it also triggers persistent changes, or plasticity, in chemosensory neurons and integrative pathways that transmit brainstem respiratory activity to respiratory motor neurons. Frequently studied models of hypoxia-induced respiratory plasticity include: (1) carotid chemosensory plasticity and metaplasticity induced by chronic intermittent hypoxia (CIH), and (2) acute intermittent hypoxia (AIH) induced phrenic long-term facilitation (pLTF) in naïve and CIH preconditioned rats. These forms of plasticity share some mechanistic elements, although they differ in anatomical location and the requirement for CIH preconditioning. Both forms of plasticity require serotonin receptor activation and formation of reactive oxygen species (ROS). While the cellular sources and targets of ROS are not well known, recent evidence suggests that ROS modify the balance of protein phosphatase and kinase activities, shifting the balance towards net phosphorylation and favoring cellular reactions that induce and/or maintain plasticity. Here, we review possible sources of ROS, and the impact of ROS on phosphorylation events relevant to respiratory plasticity.

Structural remodeling of nucleus ambiguus projections to cardiac ganglia following chronic intermittent hypoxia in C57BL/6J mice

The baroreflex control of heart rate (HR) is reduced following chronic intermittent hypoxia (CIH). Since the nucleus ambiguus (NA) plays a key role in baroreflex control of HR, we examined whether CIH remodels vagal efferent projections to cardiac ganglia. C57BL/6J mice (3-4 months of age) were exposed to either room air (RA) or CIH for 3 months. Confocal microscopy was used to examine NA axons and terminals in cardiac ganglia following Fluoro-Gold (FG) injections to label cardiac ganglia, and microinjections of tracer DiI into the left NA to anterogradely label vagal efferents. We found that: 1) Cardiac ganglia were widely distributed on the dorsal surface of the atria. Although the total number of cardiac ganglia did not differ between RA and CIH mice, the size of ganglia and the somatic area of cardiac principal neurons (PNs) were significantly decreased (P < 0.01), and the size of the PN nuclei was increased following CIH (P < 0.01). 2) NA axons entered cardiac ganglia and innervated PNs with dense basket endings in both RA and CIH mice, and the percentage of innervated PNs was similar (RA: 50 +/- 1.0%; CIH: 49 +/- 1.0%; P > 0.10). In CIH mice, however, swollen cardiac axons and terminals without close contacts to PNs were found. Furthermore, varicose endings around PNs appeared swollen and the axonal varicose area around PNs was almost doubled in size (CIH: 163.1 +/- 6.4 microm(2); RA: 88 +/- 3.9 microm(2), P < 0.01). Thus, CIH significantly altered the structure of cardiac ganglia and resulted in reorganized vagal efferent projections to cardiac ganglia. Such remodeling of cardiac ganglia and vagal efferent projections provides new insight into the effects of CIH on the brain-heart circuitry of C57BL/6J mice.

Peri-operative management of paediatric patients undergoing cardiac surgery--focus on respiratory aspects of care

Children requiring cardiac surgery present particular challenges in peri-operative respiratory management. The wide variety of conditions and operations and their varied impact on respiratory function makes dialogue with related medical staff essential. In most circumstances, cardiac performance is the main determinant of respiratory outcomes. Changing cardiologic and surgical approaches have combined to diminish the severity and frequency of pulmonary hypertensive issues and new treatment modalities are simplifying the intensive care approach. Patients with Down's syndrome and 22q11 deletion syndrome present particular issues related to anatomy, physiology and respiratory function. Certain conditions, including tetralogy of Fallot and cavopulmonary connections, present unique circumstances where respiratory management, sometimes including extubation, may assist in optimisation of cardiac performance. These and other conditions highlight the complexities of cardiopulmonary interactions. Cardiac performance remains the principal determinant of outcome after paediatric cardiac surgery and has the biggest impact on respiratory function.

Sleep apnea: epidemiology, pathophysiology, and relation to cardiovascular risk

Several studies have shown the occurrence of an independent association between obstructive sleep apnea syndrome (OSAS) and cardiovascular disease, including arterial hypertension, ischemic heart disease, and stroke. The pathogenesis of the cardiovascular complications of OSAS is still poorly understood, however. Several mechanisms are likely to be involved, including sympathetic overactivity, selective activation of inflammatory molecular pathways, endothelial dysfunction, abnormality in the process of coagulation, and metabolic dysregulation. The latter may involve insulin resistance and disorders of lipid metabolism. The aim of this review, which reports the data presented at a workshop jointly endorsed by the European Society of Hypertension and by the European Union COST action on OSAS (COST B26), is to critically summarize the evidence available to support an independent association between OSAS and cardiovascular disease.

Neural and neurobehavioral dysfunction in children with obstructive sleep apnea

Beebe discusses a new study that found that children with obstructive sleep apnea scored significantly lower than controls on tests of overall intelligence and executive function.

The effectiveness of tonsillectomy and adenoidectomy in the treatment of pediatric obstructive sleep apnea/hypopnea syndrome: a meta-analysis

OBJECTIVE

Present and evaluate the currently available literature reporting on the effectiveness of adenotonsillectomy (T/A) in treating obstructive sleep apnea/hypopnea syndrome (OSAHS) in uncomplicated pediatric patients.

STUDY DESIGN AND SETTING

Systematic review of the literature and meta-analysis of the reduction of the polysomnogram (PSG)-measured Apnea Hypopnea Index (AHI events/hour) resulting from T/A and the overall success rate of T/A in normalizing PSG measurements (%).

RESULTS

Fourteen studies met the inclusion criteria. Mean sample size was 28. All were case series (level 4 evidence). The summary change in AHI was a reduction of 13.92 events per hour (random effects model 95% CI 10.05-17.79, P < 0.001) from T/A. The summary success rate of T/A in normalizing PSG was 82.9% (random effects model 95% CI 76.2%-89.5%, P < 0.001).

CONCLUSION/SIGNIFICANCE

T/A is effective in the treatment of OSAHS. However, success rates are far below 100%, which could have far-reaching pediatric public health consequences.

EBM RATING

B-2a.

Neurobehavioral effects of obstructive sleep apnea: an overview and heuristic model

PURPOSE OF REVIEW

Obstructive sleep apnea can cause significant daytime behavioral and adaptive deficits, conventionally called 'neurobehavioral' because they are presumed to be mediated by the brain. The past few years have witnessed a marked increase in research into the neurobehavioral effects of obstructive sleep apnea, making it difficult for researchers and clinicians to stay abreast of the field. This article summarizes recent findings on the neurobehavioral effects of adult and pediatric obstructive sleep apnea, and presents a heuristic model to guide future research and clinical conceptualizations.

RECENT FINDINGS

Recent publications have suggested overlapping but distinct neurobehavioral deficits that tend to accompany obstructive sleep apnea in the adult versus childhood years. There have been exciting new developments into the mechanisms by which obstructive sleep apnea may result in these deficits, including findings based upon advanced neuroimaging tools and carefully controlled animal research. There has also been accumulating evidence for potential moderators of morbidity; that is, factors that alter the nature or severity of neurobehavioral deficit resulting from obstructive sleep apnea. Task- and context-related factors that may affect outcome have been identified, as have potential markers for individual risk and resiliency.

SUMMARY

The relation between obstructive sleep apnea and neurobehavioral deficit is probably not dependent on a single mediating mechanism, nor is it invariant across individuals. In outlining several potential moderating factors, the model presented here was designed to provide a guide for future research and a way of thinking about obstructive sleep apnea that better captures the wide variation in neurobehavioral outcome seen by practicing clinicians.

8. Investigation and treatment of upper‐airway obstruction: childhood sleep disorders I

Always take a history of snoring and sleep disturbance when reviewing children in primary care, as there is evidence that episodes of hypoxia and arousal during sleep may result in deficits in memory, attention and behaviour, in addition to the well known sequelae of growth failure, developmental delay and cor pulmonale. Check for changes in behaviour affecting school progress. To investigate for possible obstructive sleep apnoea syndrome (OSAS), clinical examination, lateral neck x-ray (adenoidal hypertrophy) and overnight oximetry (desaturation episodes) are useful screening tests, but oximetry is best used in conjunction with polysomnography. A negative oximetry test does not exclude OSAS. Polysomnography is the best method for detecting and assessing the severity of OSAS in children, and is especially helpful for prioritising treatment and evaluating the risk of perioperative complications of adenotonsillectomy. Adenotonsillectomy is thought to "cure" (ie, symptoms disappear and overnight respiratory parameters are corrected) in about 80% of children with OSAS. The remaining 20% need ongoing evaluation and treatment. Further research is needed to determine the "true" prevalence of OSAS; what degrees of severity of upper-airway obstruction lead to morbidity requiring treatment; and whether the deficits in neurocognitive function associated with sleep-disordered breathing are fully correctable.

Mechanisms of arousal from sleep and their consequences

PURPOSE OF REVIEW

In recent years, understanding of the mechanisms by which sleep is maintained and the consequences of abnormal arousal from sleep has improved rapidly. This review describes the recent insights into the nature of sleep and arousal and the particular insights gained in common disease states such as sleep-disordered breathing.

RECENT FINDINGS

Expansion of the definitions of the classic stages of non-REM and REM sleep to include consideration of the role of cyclic alternating pattern sleep as a gating mechanism for arousal and maintenance of stable sleep has led to a significant advancement in understanding the nature of normal and pathologic arousals from sleep. In addition, the effect of arousals from sleep on cerebral cortical electrophysiology and autonomic activation has been further defined, with a potential effect on clinical practice.

SUMMARY

Arousal from sleep is dependent on wake-promoting influences overwhelming forces promoting sleep. Autonomic activation and cortical arousal can significantly affect and destabilize sleep homeostasis. The understanding of sleep-respiration interactions continues to evolve. The definition of the minimal arousal event is an important research goal. It will be important in clinical practice and research to consider sleep stability domains as a complement to sleep depth staging to allow better understanding of the relative stability and instability of the system and to consider all components of the consequences of arousal.