Is there a clear link between overweight/obesity and sleep disordered breathing in children?

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.

Prevalence of obstructive sleep apnea (OSA) among preschool aged children in the general population: A systematic review

Untreated pediatric obstructive sleep apnea (OSA) is associated with significant morbidities affecting behavior, neurocognitive development, endocrine and metabolic health. This systematic review evaluated prevalence of OSA reported in population-based studies among preschoolers as early intervention may have positive effects on health and quality of life. Thirty studies were included. High degrees of heterogeneity in methods and definitions were observed between the studies. Seven studies confirmed OSA by implementing objective methods after screening for habitual snoring with only two studies utilizing polysomnography, the reference standard, testing 1.2% of the combined cohorts (n = 82/4575) to confirm disease. Diagnosis of OSA was based on utilizing retired thresholds of the apnea-hypopnea-index (AHI), AHI4%≥5/hour of sleep (hrSleep), reporting prevalence of 1.8% and 6.4%, respectively. The remaining five studies implemented relatively insensitive objective recording methods to confirm disease in a limited number of children (n = 449/2486; 18.0%), estimating prevalence in the range of 0.7%-13.0%. The remaining literature is based on implementing questionnaires only to evaluate OSA. Studies published before 2014 reported 3.3%-9.4% prevalence, while more recent studies published 2016-2023 report higher prevalence, 12.8%-20.4%, when excluding outliers. This trend suggests that prevalence of OSA may possibly have been increasing in preschoolers over the past decade.

Associations between body mass index, sleep-disordered breathing, brain structure, and behavior in healthy children

Pediatric overweight/obesity can lead to sleep-disordered breathing (SDB), abnormal neurological and cognitive development, and psychiatric problems, but the associations and interactions between these factors have not been fully explored. Therefore, we investigated the associations between body mass index (BMI), SDB, psychiatric and cognitive measures, and brain morphometry in 8484 children 9-11 years old using the Adolescent Brain Cognitive Development dataset. BMI was positively associated with SDB, and both were negatively correlated with cortical thickness in lingual gyrus and lateral orbitofrontal cortex, and cortical volumes in postcentral gyrus, precentral gyrus, precuneus, superior parietal lobule, and insula. Mediation analysis showed that SDB partially mediated the effect of overweight/obesity on these brain regions. Dimensional psychopathology (including aggressive behavior and externalizing problem) and cognitive function were correlated with BMI and SDB. SDB and cortical volumes in precentral gyrus and insula mediated the correlations between BMI and externalizing problem and matrix reasoning ability. Comparisons by sex showed that obesity and SDB had a greater impact on brain measures, cognitive function, and mental health in girls than in boys. These findings suggest that preventing childhood obesity will help decrease SDB symptom burden, abnormal neurological and cognitive development, and psychiatric problems.

Pediatric Sleep Respiratory Disorders: A Narrative Review of Epidemiology and Risk Factors

Sleep is a fundamental biological necessity, the lack of which has severe repercussions on the mental and physical well-being in individuals of all ages. The phrase "sleep-disordered breathing (SDB)" indicates a wide array of conditions characterized by snoring and/or respiratory distress due to increased upper airway resistance and pharyngeal collapsibility; these range from primary snoring to obstructive sleep apnea (OSA) and occur in all age groups. In the general pediatric population, the prevalence of OSA varies between 2% and 5%, but in some particular clinical conditions, it can be much higher. While adenotonsillar hypertrophy ("classic phenotype") is the main cause of OSA in preschool age (3-5 years), obesity ("adult phenotype") is the most common cause in adolescence. There is also a "congenital-structural" phenotype that is characterized by a high prevalence of OSA, appearing from the earliest ages of life, supported by morpho-structural abnormalities or craniofacial changes and associated with genetic syndromes such as Pierre Robin syndrome, Prader-Willi, achondroplasia, and Down syndrome. Neuromuscular disorders and lysosomal storage disorders are also frequently accompanied by a high prevalence of OSA in all life ages. Early recognition and proper treatment are crucial to avoid major neuro-cognitive, cardiovascular, and metabolic morbidities.

Polysomnographic comparison of sleep in children with obesity and normal weight without suspected sleep-related breathing disorder

Short sleep and obstructive apneas/hypopneas have been shown to be associated with childhood obesity. Still, few studies have compared sleep in children with obesity, without suspected sleep disordered breathing and normal weight peers by objective sleep measures and compared results with subjective parent assessment of sleep. Children with obesity aged 7-13 years (N = 44) and a matched group of normal weight children (N = 42) completed clinical polysomnography (Embla A10 Recording System). Parents scored their children's sleep on the Children's Sleep Habits Questionnaire (CSHQ). Mann-Whitney U tests were used to compare groups. There was a higher obstructive apnea/hypopnea index (AHI) (median obesity = 1.20 vs. median normal  = 0.66; z = -1.33, U = 560.50, p = 0.002) and number of oxygen desaturation events per hour (median obesity = 0.7 vs. median normal  = 0.2; z = -3.45, U = 402.50, p = 0.001) in the children with obesity compared to children with normal weight. The children with obesity had a significantly longer sleep duration (median obesity 8:50 h = vs. median normal = 8:32 h; z = -2.05, U = 687.00, p = 0.041), longer stage N2 sleep (median obesity = 87 min vs. median normal = 52 min; z = -2.87, U = 576.50, p = 0. 004) and shorter REM sleep (median obesity = 94 min vs. median normal = 121 min; z = 5.05, U = 1477.00, p ≤ .001). No differences were observed for time in sleep stage N1 and N3, wake time after sleep onset or the total arousal index . Further, no group differences were found on the CSHQ sleep-disordered breathing sub-scale (p = 0.399). The children with obesity demonstrated significantly more mild to moderate sleep disordered breathing than children with normal weight, although this was not corroborated by parent report.

Effect of adenotonsillectomy in children with obstructive sleep apnea and major psychiatric disorders on obstructive apnea-hypopnea index and Epworth Sleepiness Scale scores

STUDY OBJECTIVES

This study evaluates the effectiveness of adenotonsillectomy in the treatment of obstructive sleep apnea in children with major psychiatric disorders as measured by polysomnography and the Epworth Sleepiness Scale (ESS) at a tertiary children's hospital. Adults with major psychiatric disorders often have higher rates of obstructive sleep apnea and decreased response to treatment. The goal was to determine if children with serious mental illness had outcomes similar to their adult counterparts.

METHODS

A retrospective chart review was undertaken to identify children with obstructive sleep apnea and major psychiatric disorders who underwent adenotonsillectomy as part of their treatment for obstructive sleep apnea and had undergone preoperative and postoperative polysomnography as well as ESS. A multivariable model was run for each of the postoperative outcomes (ESS, obstructive apnea-hypopnea index, or body mass index percentile), adjusting for their respective preoperative value, age, and group.

RESULTS

There were 34 patients who qualified for this study and who were matched with 66 controls. There was no significant difference between the 2 groups in terms of change in ESS, obstructive apnea-hypopnea index, or body mass index percentile, both before and after adjusting for age. The only significant findings were that preoperative ESS and body mass index percentile were predictive of postoperative ESS and body mass index percentile for both groups.

CONCLUSIONS

Children with psychiatric disorders in our institution respond to surgical management of obstructive sleep apnea similar to pediatric controls without mental illness despite comorbidities and central-acting medications that may alter sleep.

Childhood Obesity and Respiratory Diseases: Which Link?

Prevalence of childhood obesity is progressively increasing, reaching worldwide levels of 5.6% in girls and of 7.8% in boys. Several evidences showed that obesity is a major preventable risk factor and disease modifier of some respiratory conditions such as asthma and Obstructive Sleep Apnea Syndrome (OSAS). Co-occurrence of asthma and obesity may be due to common pathogenetic factors including exposure to air pollutants and tobacco smoking, Western diet, and low Vitamin D levels. Lung growth and dysanapsis phenomenon in asthmatic obese children play a role in impaired respiratory function which appears to be different than in adults. Genes involved in both asthma and obesity have been identified, though a gene-by-environment interaction has not been properly investigated yet. The identification of modifiable environmental factors influencing gene expression through epigenetic mechanisms may change the natural history of both diseases. Another important pediatric respiratory condition associated with obesity is Sleep-Disordered Breathing (SDB), especially Obstructive Sleep Apnea Syndrome (OSAS). OSAS and obesity are linked by a bidirectional causality, where the effects of one affect the other. The factors most involved in the association between OSAS and obesity are oxidative stress, systemic inflammation, and gut microbiota. In OSAS pathogenesis, obesity's role appears to be mainly due to mechanical factors leading to an increase of respiratory work at night-time. However, a causal link between obesity-related inflammatory state and OSAS pathogenesis still needs to be properly confirmed. To prevent obesity and its complications, family education and precocious lifestyle changes are critical. A healthy diet may lead to an improved quality of life in obese children suffering from respiratory diseases. The present review aimed to investigate the links between obesity, asthma and OSAS, focusing on the available evidence and looking for future research fields.

Central Sleep Apnea Alters Neuronal Excitability and Increases the Randomness in Sleep-Wake Transitions

OBJECTIVE

While most studies on Central Sleep Apnea (CSA) have focused on breathing and metabolic disorders, the neuronal dysfunction that causes CSA remains largely unknown. Here, we investigate the underlying neuronal mechanism of CSA by studying the sleep-wake dynamics as derived from hypnograms.

METHODS

We analyze sleep data of seven groups of subjects: healthy adults (n = 48), adults with obstructive sleep apnea (OSA) (n = 29), adults with CSA (n = 25), healthy children (n = 40), children with OSA (n = 18), children with CSA (n = 73) and CSA children treated with CPAP (n = 10). We calculate sleep-wake parameters based on the probability distributions of wake-bout durations and sleep-bout durations. We compare these parameters with results obtained from a neuronal model that simulates the interplay between sleep- and wake-promoting neurons.

RESULTS

We find that sleep arousals of CSA patients show a characteristic time scale (i.e., exponential distribution) in contrast to the scale-invariant (i.e., power-law) distribution that has been reported for arousals in healthy sleep. Furthermore, we show that this change in arousal statistics is caused by triggering more arousals of similar durations, which through our model can be related to a higher excitability threshold in sleep-promoting neurons in CSA patients.

CONCLUSIONS

We propose a neuronal mechanism to shed light on CSA pathophysiology and a method to discriminate between CSA and OSA. We show that higher neuronal excitability thresholds can lead to complex reorganization of sleep-wake dynamics.

SIGNIFICANCE

The derived sleep parameters enable a more specific evaluation of CSA severity and can be used for CSA diagnosis and monitor CSA treatment.

Sleep Timing During Adolescence: A Latent Transition Analysis Approach

Objective/Background: This paper utilized a person-centered approach to examine individual differences in sleep timing cross-sectionally and prospectively in adolescents. Participants: Data from Waves 5 and 6 of the Longitudinal Study of Australian Children were used. At Wave 5, the sample included 3,552 Australian adolescents aged 12-13 years (51% males, 49% females); 84% provided data at two-year follow-up (Wave 6). Methods: Through structured interviews, adolescents provided information on sleep timing (bedtimes, sleep-onset times, and wake times) on weekends and weekdays, and relevant covariates. Latent profile analysis identified sleep profiles at Waves 5 and 6 separately; latent transition analysis examined stability and change in profiles across time. Results: Six sleep timing profiles were identified at age 12-13 years: Early Larks (n = 228; 6.4%); Larks (n = 1257; 35.4%); Intermediate (n = 1311; 36.9%); Owls (n = 351; 9.9%); Variable Owls (n = 308; 8.7%); and, Late Owls (n = 97; 2.7%). Six similar profiles were identified at age 14-15 years. The latent transition analysis indicated that the Early Larks, Larks, and Intermediate profiles were more stable over time compared with the Owls, Variable Owls, and Late Owls profiles. Higher body mass index (BMI) and longer screen time predicted transitions from Larks and Early Larks to the Owls, Variable Owls, and Late Owls profiles. Conclusions: Many adolescents showed healthy sleep timing, which continued with age. However, the Variable Owls, Owls, and Late Owls profiles reflected less healthy and more variable sleep patterns that may require targeted interventions.

The association between excessive screen-time behaviors and insufficient sleep among adolescents: Findings from the 2017 youth risk behavior surveillance system

Although studies have examined the association between television viewing and poor sleep quality, few studies have considered the association between excessive screen-time behaviors and insufficient sleep among adolescents drawing on a large nationally representative sample. The objective of this study was to examine the association between excessive screen-time behaviors and insufficient sleep among adolescents. Data for this study came from the 2017 Youth Risk Behavior Survey. A sample of 14,603 adolescents aged 14-18 years (51.5% female) was analyzed using logistic regression with insufficient sleep as the outcome variable and excessive screen-time behaviors as the main explanatory variable. Of the 14,603 adolescents, almost three out of four (74.8%) had less than 8 h of sleep on an average school night, and about 43% engaged in excessive screen-time behaviors on an average school day. Controlling for all other predictors, odds were 1.34 times higher for adolescents who engaged in excessive screen-time behaviors to have insufficient sleep when compared to adolescents who did not engage in excessive screen-time behaviors (AOR = 1.34, p < .001, 95% CI = 1.22-1.48). School-based behavior interventions that focus on reduction in excessive screen-time and sedentary behaviors might be beneficial in reducing excessive screen-time behaviors and consequently improve sleep quality among adolescents.

Outcomes of Tongue Base Reduction and Lingual Tonsillectomy for Residual Pediatric Obstructive Sleep Apnea after Adenotonsillectomy

Introduction  Upper airway obstruction at multiple sites, including the velum, the oropharynx, the tongue base, the lingual tonsils, or the supraglottis, has been resulting in residual obstructive sleep apnea (OSA) after tonsillectomy and adenoidectomy (TA). The role of combined lingual tonsillectomy and tongue base volume reduction for treatment of OSA has not been studied in nonsyndromic children with residual OSA after TA. Objective  To evaluate the outcomes of tongue base volume reduction and lingual tonsillectomy in children with residual OSA after TA. Methods  A retrospective chart review was conducted to obtain information on history and physical examination, past medical history, findings of drug-induced sleep endoscopy (DISE), of polysomnography (PSG), and surgical management. Pre- and postoperative PSGs were evaluated to assess the resolution of OSA and to determine the improvement in the obstructive apnea-hypopnea index (oAHI) before and after the surgery. Results  A total of 10 children (5 male, 5 female, age range: 10-17 years old, mean age: 14.5 ± 2.6 years old) underwent tongue base reduction and lingual tonsillectomy. Drug-induced sleep endoscopy (DISE) revealed airway obstruction due to posterior displacement of the tongue and to the hypertrophy of the lingual tonsils. All of the patients reported subjective improvement in the OSA symptoms. All of the patients had improvement in the oAHI. The postoperative oAHI was lower than the preoperative oAHI ( p  < 0.002). The postoperative apnea-hypopnea index during rapid eye movement sleep (REM-AHI) was lower than the preoperative REM-AHI ( p  = 0.004). Obstructive sleep apnea was resolved in children with normal weight. Overweight and obese children had residual OSA. Nonsyndromic children had resolution of OSA or mild OSA after the surgery. Conclusions  Tongue base reduction and lingual tonsillectomy resulted in subjective and objective improvement of OSA in children with airway obstruction due to posterior displacement of the tongue and to hypertrophy of the lingual tonsils.

Obstructive sleep apnea in children and adolescents with and without obesity

PURPOSE

To investigate the prevalence of obstructive sleep apnea (OSA) in children referred for obesity treatment, and to compare the prevalence with that of a normal-weight group. Moreover, we examined the association between Body Mass Index Standard Deviation Score (BMI SDS) and the Apnea-Hypopnea Index (AHI).

METHODS

This cross-sectional study included 139 children aged 7-18 years with overweight/obesity (BMI SDS >1.28) recruited from an obesity treatment clinic. The normal-weight group consisted of 33 children (BMI SDS ≤ 1.28) aged 7-18 years recruited from schools. Sleep examinations were performed using a type 3 portable sleep monitor (Nox T3). OSA was defined as AHI ≥ 2. Height and weight were measured and the tonsillar size was clinically estimated using the Brodsky scale.

RESULTS

The OSA prevalence was 44.6% in children with overweight/obesity compared with 9.1% in the normal-weight group (p = 0.0002), and the relative risk of OSA was 4.9 (95% CI 1.6-14.7). In a logistic regression, a one-unit increase in the BMI SDS increased the odds of having OSA by a factor of 1.92 independent of age, sex, tonsillar hypertrophy, and asthma (95% CI 1.33-2.76, p = 0.0005). A generalized linear regression adjusted for the same variables revealed an association between BMI SDS and AHI (a one-unit increase in the BMI SDS equaled an average increase in the AHI of 35% (95% CI 19-53%, p < 0.0001)).

CONCLUSIONS

In this study, children with overweight/obesity had a significantly higher prevalence of OSA compared with a normal-weight group. Increased BMI SDS was associated with increased AHI.

The shifting relationship between weight and pediatric obstructive sleep apnea: A historical review

OBJECTIVES

For more than a century, pediatric obstructive sleep apnea (OSA) was associated with failure to thrive. However, that association has faded over the last few decades. A 21st century child with OSA is much more likely to be overweight than underweight. This raises the question: Has pediatric OSA changed over time, or has the rise of childhood obesity in the United States created a new, separate disease? This literature review explores the historical shift in the relationship between weight and OSA, and the associated changes in treatment.

RESULTS

We demonstrate a clear transition in the prevalence of failure to thrive and obesity in the OSA literature in the mid-2000s. What is less clear is whether these two clinical phenotypes should be considered two distinct diseases, or whether subtle differences in one set of pathophysiologic pathways-adenotonsillar hypertrophy, altered inflammation, and increased energy expenditure-can lead to divergent metabolic outcomes. More research is needed to fully elucidate the pathophysiology of OSA in children with obesity.

CONCLUSIONS

We may need new and different treatments for obesity-associated OSA as adenotonsillectomy-which is effective at reversing failure to thrive in OSA-is not as effective at treating OSA in children with obesity. One option is drug-induced sleep endoscopy, which could personalize and improve surgical treatment of OSA. There is some evidence that therapies used for OSA in adults (e.g., weight loss and positive airway pressure) are also helpful for overweight/obese children with OSA. Laryngoscope, 129:2414-2419, 2019.

ASMBS pediatric metabolic and bariatric surgery guidelines, 2018

The American Society for Metabolic and Bariatric Surgery Pediatric Committee updated their evidence-based guidelines published in 2012, performing a comprehensive literature search (2009-2017) with 1387 articles and other supporting evidence through February 2018. The significant increase in data supporting the use of metabolic and bariatric surgery (MBS) in adolescents since 2012 strengthens these guidelines from prior reports. Obesity is recognized as a disease; treatment of severe obesity requires a life-long multidisciplinary approach with combinations of lifestyle changes, nutrition, medications, and MBS. We recommend using modern definitions of severe obesity in children with the Centers for Disease Control and Prevention age- and sex-matched growth charts defining class II obesity as 120% of the 95th percentile and class III obesity as 140% of the 95th percentile. Adolescents with class II obesity and a co-morbidity (listed in the guidelines), or with class III obesity should be considered for MBS. Adolescents with cognitive disabilities, a history of mental illness or eating disorders that are treated, immature bone growth, or low Tanner stage should not be denied treatment. MBS is safe and effective in adolescents; given the higher risk of adult obesity that develops in childhood, MBS should not be withheld from adolescents when severe co-morbidities, such as depressed health-related quality of life score, type 2 diabetes, obstructive sleep apnea, and nonalcoholic steatohepatitis exist. Early intervention can reduce the risk of persistent obesity as well as end organ damage from long standing co-morbidities.

Obesity in children with different risk factors for obstructive sleep apnea: a community-based study

This study investigated the association between obesity and obstructive sleep apnea (OSA) in preschool and school-age children. Parents of obese and randomly chosen normal weight children completed a questionnaire on sleep-related symptoms, demography, family, and medical history. All subjects were invited to undergo polysomnography (PSG). OSA cases were defined as obstructive apnea hypopnea index (OAHI) ≥1. A total of 5930 children were studied with 9.5% obese (11.9% boys/6.1% girls), 205/2680 preschool and 360/3250 school children. There were 1030 children (535 obese/495 normal weight) who underwent PSG. OSA was higher in obese children and obese school children had higher OAHI, arousal index, and shorter total sleep time. However, there was no positive correlation between OSA and body mass index (BMI). The main risk factors for OSA in preschool children were adenotonsillar hypertrophy and recurrent respiratory tract infection. The main cause for OSA in school children was a history of parental snoring and obesity. Mallampati scores and sleep-related symptoms were found to be associated with OSA in both preschool and school children.

CONCLUSION

We demonstrated differential risk factors for OSA in obese children, which suggest that a different mechanism may be involved in OSA development in preschool and school-age children.

WHAT IS KNOWN

Various risk factors have been reported in obese children with OSA owing to the different age and different study design. Obese children have a higher prevalence and severity of obstructive sleep apnea (OSA). OSA risk factors in obese children are affected by different ages and study designs.

WHAT IS NEW

A differential prevalence and risk factors for obese preschool and school-age children with OSA has been demonstrated.

The influence of snoring, mouth breathing and apnoea on facial morphology in late childhood: a three-dimensional study

OBJECTIVE

To explore the relationship between the prevalence of sleep disordered breathing (SDB) and face shape morphology in a large cohort of 15-year-old children.

DESIGN

Observational longitudinal cohort study

SETTING

Avon Longitudinal Study of Parents and Children (ALSPAC), South West of England.

PARTICIPANTS

Three-dimensional surface laser scans were taken for 4784 white British children from the ALSPAC during a follow-up clinic. A total of 1724 children with sleep disordered breathing (SDB) and 1862 healthy children were identified via parents' report of sleep disordered symptoms for their children. We excluded from the original cohort all children identified as having congenital abnormalities, diagnoses associated with poor growth and children with adenoidectomy and/or tonsillectomy.

MAIN OUTCOME MEASURES

Parents in the ALSPAC reported sleep disordered symptoms (snoring, mouth breathing and apnoea) for their children at 6, 18, 30, 42, 57, 69 and 81 months. Average facial shells were created for children with and without SDB in order to explore surface differences.

RESULTS

Differences in facial measurements were found between the children with and without SDB throughout early childhood. The mean differences included an increase in face height in SDB children of 0.3 mm (95% CI -0.52 to -0.05); a decrease in mandibular prominence of 0.9° (95% CI -1.30 to -0.42) in SDB children; and a decrease in nose prominence and width of 0.12 mm (95% CI 0.00 to 0.24) and 0.72 mm (95% CI -0.10 to -0.25), respectively, in SDB children. The odds of children exhibiting symptoms of SDB increased significantly with respect to increased face height and mandible angle, but reduced with increased nose width and prominence.

CONCLUSIONS

The combination of a long face, reduced nose prominence and width, and a retrognathic mandible may be diagnostic facial features of SBD that may warrant a referral to specialists for the evaluation of other clinical symptoms of SDB.

Links and risks associated with adenotonsillectomy and obesity

Adenotonsillectomy (A&T) is a very common surgical procedure in children. Over the past 20 years the principal indication for A&T in children has changed from recurrent adenotonsillitis to obstructive sleep apnea. The physiopathology of obstructive sleep apnea syndrome (OSAS) is multifactorial and obesity has been shown to be one of the main factors correlated with its occurrence. On the other hand, the prevalence and severity of childhood obesity have become a veritable epidemic problem in the past 30 years. So the increasing prevalence of obesity in children and high prevalence of obstructive sleep apnea in obese children implies that an increasing number of these children will present for A&T. Due to more prevalent anatomical alterations of the oronasopharyngeal airways, it is often difficult to predict operation success in obese children. However, previous studies supports that although the risk of presence of residual symptoms of OSAS and airway-related perioperative complication in obese may be more than nonobese group, A&T is effective to reduce obstructive symptoms and improve quality of life in obese children with OSAS.

[Detection and treatment of respiratory disorders in obese children: Obstructive sleep apnea syndrome and obesity hypoventilation syndrome]

Pediatric obesity may induce multiple complications, including cardiovascular and metabolic problems in adulthood. It may also cause respiratory disorders, which are not usually the first-intention diagnosis by physicians. The aim of this study was to evaluate how investigations had been performed in obese children referred to Timone Pediatric Hospital.

PATIENTS AND METHODS

A retrospective study of children referred to our department for severe non-syndromic obesity was conducted. The clinical features comprised history, anthropometric parameters, dietary habits, acanthosis nigricans, symptoms of obstructive sleep apnea syndrome (OSAS) as well as the paraclinical endocrine markers, blood gases, and sleep recordings.

RESULTS

Of 102 patients (mean age, 10.5±3.3 years; BMI Z-score, 4.52±1.5), 29.4% had OSAS symptoms (n=30). Nine had a pathological polysomnography confirming OSAS. Eight of them required ventilation: these children were the most severe with an earlier weight gain (2.17±1.2 years vs. 4.0±2.2 years; P=0.01) and a higher BMI Z-score (7.2±2.3 vs. 4.3±1.1; P=0.027). Obesity hypoventilation syndrome (OHS) was diagnosed in 3.9% of these children (n=4).

CONCLUSION

Diagnosis of OSAS and OHS, often overlooked in obese children, requires a systematic approach and early clinical detection of respiratory disorders. Better accessibility to sleep respiratory explorations would improve quality of care for these children.

Lateral facial profile may reveal the risk for sleep disordered breathing in children--the PANIC-study

OBJECTIVE

To evaluate the lateral view photography of the face as a tool for assessing morphological properties (i.e. facial convexity) as a risk factor for sleep disordered breathing (SDB) in children and to test how reliably oral health and non-oral healthcare professionals can visually discern the lateral profile of the face from the photographs.

MATERIALS AND METHODS

The present study sample consisted of 382 children 6-8 years of age who were participants in the Physical Activity and Nutrition in Children (PANIC) Study. Sleep was assessed by a sleep questionnaire administered by the parents. SDB was defined as apnoeas, frequent or loud snoring or nocturnal mouth breathing observed by the parents. The facial convexity was assessed with three different methods. First, it was clinically evaluated by the reference orthodontist (T.I.). Second, lateral view photographs were taken to visually sub-divide the facial profile into convex, normal or concave. The photos were examined by a reference orthodontist and seven different healthcare professionals who work with children and also by a dental student. The inter- and intra-examiner consistencies were calculated by Kappa statistics. Three soft tissue landmarks of the facial profile, soft tissue Glabella (G`), Subnasale (Sn) and soft tissue Pogonion (Pg`) were digitally identified to analyze convexity of the face and the intra-examiner reproducibility of the reference orthodontist was determined by calculating intra-class correlation coefficients (ICCs). The third way to express the convexity of the face was to calculate the angle of facial convexity (G`-Sn-Pg`) and to group it into quintiles. For analysis the lowest quintile (≤164.2°) was set to represent the most convex facial profile.

RESULTS

The prevalence of the SDB in children with the most convex profiles expressed with the lowest quintile of the angle G`-Sn-Pg` (≤164.2°) was almost 2-fold (14.5%) compared to those with normal profile (8.1%) (p = 0.084). The inter-examiner Kappa values between the reference orthodontist and the other examiners for visually assessing the facial profile with the photographs ranged from poor-to-moderate (0.000-0.579). The best Kappa values were achieved between the two orthodontists (0.579). The intra-examiner Kappa value of the reference orthodontist for assessing the profiles was 0.920, with the agreement of 93.3%. In the ICC and its 95% CI between the two digital measurements, the angles of convexity of the facial profile (G`-Sn-Pg`) of the reference orthodontist were 0.980 and 0.951-0.992.

CONCLUSION

In addition to orthodontists, it would be advantageous if also other healthcare professionals could play a key role in identifying certain risk features for SDB. However, the present results indicate that, in order to recognize the morphological risk for SDB, one would need to be trained for the purpose and, as well, needs sufficient knowledge of the growth and development of the face.

Associations between adenotonsillar hypertrophy, age, and obesity in children with obstructive sleep apnea

OBJECTIVE

To investigate the contributions of adenoid and tonsil size to childhood obstructive sleep apnea (OSA) and the interactions between adenotonsillar hypertrophy, age, and obesity in children with OSA.

METHODS

In total, 495 symptomatic patients were recruited. The patients were assigned to four groups according to age: toddler (age 1-3, n=42), preschool (age 3-6, n=164), school (age 6-12, n=200), and adolescence (age 12-18, n=89). All subjects had tonsil size graded by otolaryngologists, adenoid size determined on lateral radiographs (Fujioka method), and a full-night polysomnography. The apnea-hypopnea index (AHI), adenoid size, and tonsil size were compared in obese and non-obese children in the four age groups. Adjusted odds ratios (ORs) and 95% confidence interval (CI) of adenotonsillar hypertrophy and OSA risk were estimated by multi-logistic regression.

RESULTS

The AHI was positively related to tonsil grade (r=0.33, p <0.001) and adenoid size (r=0.24, p <0.01) in all patients. Tonsil grade was positively related to AHI in all four age groups. Adenoid size was positively related to AHI in the toddler, preschool, school groups, but not in the adolescent group (r=0.11, p=0.37). Tonsil grade and adenoid size were both positively related to AHI in obese and non-obese children. In the regression model, obesity (OR=2.89; 95% CI 1.47-5.68), tonsillar hypertrophy (OR=3.15; 95% CI 2.04-4.88), and adenoidal hypertrophy (OR=1.89; 95% CI 1.19-3.00) significantly increased OSA risk.

CONCLUSIONS

Adenotonsillar hypertrophy and obesity are the major determinants of OSA in children. However, the influence of adenoid size decreases in adolescence.

Assessing the relationship between obesity and asthma in adolescent patients: a review

The parallel rise in the prevalence of obesity and asthma over the last several decades has led to an extensive line of investigation into the relationship between these two conditions. This review will discuss evidence from laboratory-based studies, observational clinical studies, and clinical trials that suggests that obesity adversely influences asthma through multiple mechanisms. The effect of obesity on asthma during adolescence, including asthma incidence, the severity and control of existing asthma, lung function, and exacerbations, will be reviewed.

Craniofacial morphology but not excess body fat is associated with risk of having sleep-disordered breathing--the PANIC Study (a questionnaire-based inquiry in 6-8-year-olds)

We investigated the associations of dental occlusion, other craniofacial features and body fat with paediatric sleep-disordered breathing (SDB) in a representative population sample of 491 Finnish children 6-8 years of age. Overweight and obesity were defined using age- and sex-specific body mass index cutoffs by International Obesity Task Force (IOTF) criteria. Body fat percentage was assessed by dual-energy X-ray absorptiometry. Facial proportions, dental occlusion and soft tissue structures were evaluated by an orthodontist. Sleep was assessed by a sleep questionnaire administered by the parents. SDB was defined as apnoeas, frequent or loud snoring or nocturnal mouth breathing observed by the parents. The prevalence of SDB was 9.9 % with no difference between boys and girls. The median (interquartile range) of body fat percentage was 20.6 (17.4-27.1) in girls and 15.0 (11.4-21.6) in boys. Altogether 11.4 % of boys and 15.6 % of girls were classified as having overweight or obesity according to the IOTF criteria. There was no difference in the prevalence of overweight, obesity or body fat percentage between children with SDB and those without it. Children with tonsillar hypertrophy had a 3.7 times higher risk of suffering SDB than those with normal size tonsils after adjustment for age, sex and body fat percentage. Furthermore, children with cross bite had a 3.3 times higher risk of having SDB than those without cross bite, and children with a convex facial profile had a 2.6 times higher risk of having SDB than those with a normal facial profile.

CONCLUSION

Abnormal craniofacial morphology, but not excess body fat, is associated with an increased risk of having SDB in 6-8-year-old children. A simple model of necessary clinical examinations (i.e. facial profile, dental occlusion and tonsils) is recommended to recognize children with an increased risk of SDB.

Baroreflex sensitivity is associated with sleep-related breathing problems in adolescents

OBJECTIVES

To examine the relationship between sleep-related breathing problems (SRBPs) and baroreflex sensitivity (BRS) among adolescents and assesses whether body mass influences this relationship.

STUDY DESIGN

SRBPs were assessed in 106 adolescents aged 11-14 years using the Pediatric Sleep Questionnaire. Body mass index (BMI) was calculated, and 5 minutes of continuous beat-to-beat blood pressure (Finapres) and R-R interval were recorded (standard electrocardiogram) after 15 minutes of supine rest. Spectral indices were computed using fast Fourier transform, and transfer function analysis was used to compute BRS.

RESULTS

Regression analyses indicate an interaction between BMI and SRBPs (b=-.151, P=.015) on BRS. Graphing the interaction showed that those with higher SRBP scores had lower BRS but that this effect was stronger for those with higher BMI.

CONCLUSIONS

Adolescents with elevated SRBP scores had lower BRS. In addition, higher BMI amplified the risk of higher SRBP scores on BRS.

Symptoms at presentation in children with sleep-related disorders

OBJECTIVE

To assess the link between sleep-disordered breathing and cognitive function in children. To identify correlations among polysomnography, upper respiratory infections, or cephalometric as well as rhinometric measures.

METHODS

This study is based on a questionnaire survey of snoring in a population cohort of 2100 children. Altogether, 44 snorers and 51 non-snorers participated in this community based clinical study. All children underwent polysomnography, cephalometry and rhinometric measurements. In addition, a standardized test of intelligence (WPPSI-R), a neuropsychological test battery (NEPSY) and a parental questionnaire on behavioral symptoms (CBCL) were administered.

RESULTS

Frequently snoring children scored lower in Language functions (Comprehension of Instructions, P=0.01; Speeded naming, P=0.007) and had more internalizing problems, P=0.04 than did the non-snoring group. However, the polysomnography parameters of these snoring children revealed no major sleep-related breathing disorder. OAHI, mean lowest SpO(2) and respiratory effort correlated with Auditory Attention (P<0.05), Body Part Naming (P<0.05) and Memory (P<0.05). Tonsillar size correlated with OAHI (P<0.01) and respiratory effort (P=0.01) and respiratory airflow (P<0.01). In cephalometry, the minimal distance from velum to posterior wall was shorter showing the shorter length among snorers than non-snorers, 5.5mm vs. 6.6mm, respectively (P<0.05). Recurrent upper respirataory infections (URIs) were common among the snoring than non-snoring children (P=0.01). Children suffering recurrent URIs have more somatic complaints than children without recurrent URIs (P<0.01).

CONCLUSIONS

Snoring children with apparently normal and/or no obstructive apnea, hypopnea, or marked SpO(2) desaturations appear to suffer impairment in neurocognitive and behavioral functions compared to non-snoring children. These snoring children did not reveal any major abnormalities of polysomnographic parameters, such as sleep-related breathing disorder, including partial upper airway obstruction. Polysomnographic parameters also correlated poorly with neurocognitive test results in these snoring children. The correlations between polysomnography and upper respiratory infections, with cephalometric and rhinometric measures, were also poor.

Impact of lifestyle and technology developments on sleep

Although the physiological and psychological mechanisms involved in the development of sleep disorders remain similar throughout history, factors that potentiate these mechanisms are closely related to the "zeitgeist", ie, the sociocultural, technological and lifestyle trends which characterize an era. Technological advancements have afforded modern society with 24-hour work operations, transmeridian travel and exposure to a myriad of electronic devices such as televisions, computers and cellular phones. Growing evidence suggests that these advancements take their toll on human functioning and health via their damaging effects on sleep quality, quantity and timing. Additional behavioral lifestyle factors associated with poor sleep include weight gain, insufficient physical exercise and consumption of substances such as caffeine, alcohol and nicotine. Some of these factors have been implicated as self-help aids used to combat daytime sleepiness and impaired daytime functioning. This review aims to highlight current lifestyle trends that have been shown in scientific investigations to be associated with sleep patterns, sleep duration and sleep quality. Current understanding of the underlying mechanisms of these associations will be presented, as well as some of the reported consequences. Available therapies used to treat some lifestyle related sleep disorders will be discussed. Perspectives will be provided for further investigation of lifestyle factors that are associated with poor sleep, including developing theoretical frameworks, identifying underlying mechanisms, and establishing appropriate therapies and public health interventions aimed to improve sleep behaviors in order to enhance functioning and health in modern society.

Obesity and cardiovascular risk in children and adolescents

The global prevalence of overweight and obesity in children and adolescents has increased substantially over the past several decades. These trends are also visible in developing economies like India. Childhood obesity impacts all the major organ systems of the body and is well known to result in significant morbidity and mortality. Obesity in childhood and adolescence is associated with established risk factors for cardiovascular diseases and accelerated atherosclerotic processes, including elevated blood pressure (BP), atherogenic dyslipidemia, atherosclerosis, metabolic syndrome, type II diabetes mellitus, cardiac structural and functional changes and obstructive sleep apnea. Probable mechanisms of obesity-related hypertension include insulin resistance, sodium retention, increased sympathetic nervous system activity, activation of the renin-angiotensin-aldosterone system and altered vascular function. Adiposity promotes cardiovascular risk clustering during childhood and adolescence. Insulin resistance has a strong association with childhood obesity. A variety of proinflammatory mediators that are associated with cardiometabolic dysfunction are also known to be influenced by obesity levels. Obesity in early life promotes atherosclerotic disease in vascular structures such as the aorta and the coronary arteries. Childhood and adolescent adiposity has strong influences on the structure and function of the heart, predominantly of the left ventricle. Obesity compromises pulmonary function and increases the risk of sleep-disordered breathing and obstructive sleep apnea. Neglecting childhood and adolescent obesity will compromise the cardiovascular health of the pediatric population and is likely to result in a serious public health crisis in future.

[Childhood obesity and sleep-related breathing disorders]

INTRODUCTION

The increasing prevalence of childhood obesity leads to an increase risk of sleep-disordered breathing and may exacerbate their comorbidities.

PURPOSE

To assess the rate of obesity in children with sleep-disordered breathing and to study the possible clinical and epidemiological differences between children with and without overweight in a private hospital in the Mediterranean area.

MATERIALS AND METHODS

We prospectively studied 340 children between 2 and 10 years. There were 170 children with sleep-disordered breathing (study group) and 170 healthy children (control group). In the problem group, the apnea-hypopnea index was around 7.61 ± 6.3.

RESULTS

The comparison of the percentage of cases with a BMI percentile ≥85 (overweight) between problem and control groups (44: 25.9% vs 34: 20%) or with a BMI ≥95 (obesity) (30: 17.6% vs 20: 11.8%) showed no statistically-significant differences. In addition, the comparison of clinical and epidemiological variables in the problem group, cases with (44/170: 25.9%) and without (126/170: 74.1%) overweight, did not show significant differences in any of the parameters analysed.

CONCLUSION

In the population studied, it does not appear that the group of children with sleep breathing disorders presents higher rates of obesity, nor does obesity influence its presentation clinically. These results had probably been influenced by the characteristics of the studied population and therefore should not be an obstacle for being attentive to the possible association of respiratory disease to obesity and its negative consequences.

The association between obstructive sleep apnea and dietary choices among obese individuals during middle to late childhood

OBJECTIVE

Determine whether obstructive sleep apnea (OSA) is associated with the dietary choices of obese individuals during middle- to late-childhood. It was hypothesized that OSA would be associated with increased caloric content of a dinner order, particularly with high carbohydrate food choices. Secondarily, we examined the relationships between sleep duration and dietary choices.

METHODS

42 obese subjects aged 10-16.9 years participated in a cross-sectional study that involved systematic collection of sleep duration (based on actigraphy), presence and severity of obstructive sleep apnea (obstructive apnea+hypopnea index [AHI] from inpatient polysomnography) and the macronutrient content of dinners ordered from a standardized hospital menu the evening before the polysomnogram.

RESULTS

Primary analyses using Spearman rank-order correlations found that AHI was significantly associated with total calories, as well as grams of fat and carbohydrate, but not protein. These macronutrient variables did not correlate with sleep duration across a week, nor the night before the meal. Findings were unchanged after correcting for age- and sex-adjusted BMI.

CONCLUSIONS

More severe OSA appears to be associated with an increased preference for calorie-dense foods that are high in fat and carbohydrates in a manner that is independent of degree of obesity. Although this novel finding awaits replication, it has potential implications for the clinical care of obese youth and individuals with OSA, adds to the limited data that relate sleep to dietary choices and may have implications for OSA-related morbidity.

[Epidemiology. Risk factors and genetic influence]

Epidemiological studies of sleep-disordered breathing in broad population samples are scarce. Nevertheless, currently available data indicate that habitual snoring is present in 7.45 % (95 % CI: 5.75-9.61) of the child population. Approximately 10 % of habitual snorers develop sleep apnea. However, in children with associated comorbidity (obesity, asthma…) or clinical symptoms of sleep-disordered breathing, the association between snoring and sleep apnea is significantly increased. The prevalence of sleep apnea according to parents' or guardians' observation of apnea episodes is 0.2-4 %. When the diagnosis is based on questionnaires administered directly to parents, the prevalence increases to 4-11 %. If diagnosis is made by objective means, the prevalence ranges from 1-4 %. Obesity is currently a major risk factor. In obese children, the prevalence of sleep apnea oscillates between 4.69 % and 6.6 % and consequently screening of sleep-disordered breathing in obese patients with or without suggestive symptoms should be routine. Genetic factors strongly influence sleep-disordered breathing and seem to account for 35-40 % of the variance in this disorder, although their precise role has yet to be clarified. Genetic study opens up an important gateway in the future medical approach to sleep-disordered breathing.

Treatment of childhood obstructive sleep apnea

OPINION STATEMENT

An array of surgical, medical and orthodontic treatments is available for treating childhood obstructive sleep apnea. Adenotonsillectomy remains the first choice in treatment, with a need for subsequent clinical and polysomnographic reassessment in selected cases to determine residual sleep-disordered breathing. Residual obstructive sleep apnea is more likely in patients with craniofacial abnormalities or obesity. It may require the use of a positive airway pressure breathing device. Topical corticosteroids, leukotriene antagonists, weight reduction, and positional therapy also play a role in ameliorating childhood obstructive sleep apnea. The published evidence for the efficacy of various treatment modalities consists largely of case-controlled studies and case reports.

Update on pediatric sleep-disordered breathing

Pediatric sleep-disordered breathing (SDB) includes an increasingly recognized, highly prevalent, yet still underdiagnosed spectrum of respiratory disorders, the most common and clinically significant of which is obstructive sleep apnea. SDB is linked with significant end-organ dysfunction across various systems, particularly with cardiovascular, neurocognitive, and metabolic consequences. This review summarizes recent advances in understanding of pediatric SDB and discusses the challenges inherent in diagnosing and treating children with SDB.

Obstructive sleep apnea and the metabolic syndrome

Obstructive sleep apnea (OSA) and the metabolic syndrome have a strong association with each other owing to their common feature of obesity, but an association independent of obesity has been demonstrated in several studies. There is also evidence, of varying strengths, from epidemiologic and clinical studies, for the independent association between OSA and individual core components of the metabolic syndrome, including hypertension, insulin resistance and dyslipidemia. To date, the data are strongest for hypertension, while data for adverse glucose or lipid metabolism are more controversial. Obesity and other factors, such as alcohol drinking and smoking, obviously pose major confounding hurdles to the clarification of the causal or aggravational role of OSA on cardiometabolic risks. Recurrent episodes of obstructed breathing notably result in intermittent hypoxemia and sleep fragmentation, and these may in turn lead to many adverse body responses, including sympathetic activation, neurohumeral changes and inflammation, which are the seeds for cardiometabolic dysfunctions, such as atherosclerosis and diabetes mellitus. Evidence from translational studies or animal/cell work are forthcoming in the delineation of these pathogenetic mechanisms.

Sleep and culture in children with medical conditions

OBJECTIVES

To provide an integrative review of the existing literature on the interrelationships among sleep, culture, and medical conditions in children.

METHODS

A comprehensive literature search was conducted using PubMed, Medline, and PsychINFO computerized databases and bibliographies of relevant articles.

RESULTS

Children with chronic illnesses experience more sleep problems than healthy children. Cultural beliefs and practices are likely to impact the sleep of children with chronic illnesses. Few studies have examined cultural factors affecting the relationship between sleep and illness, but existing evidence suggests the relationship between sleep and illness is exacerbated for diverse groups.

CONCLUSIONS

Sleep is of critical importance to children with chronic illnesses. Cultural factors can predispose children both to sleep problems and to certain medical conditions. Additional research is needed to address the limitations of the existing literature, and to develop culturally sensitive interventions to treat sleep problems in children with chronic illnesses.

Sleep-disordered breathing in obese children: the southern Italy experience

BACKGROUND

The association of obesity with sleep-associated respiratory disturbances, which has traditionally been described as a problem in adults, actually originates in childhood. We sought an association between sleep-disordered breathing (SDB) and overweight and/or obesity in a large cohort of school- and preschool-aged children in Southern Italy.

METHODS

One thousand two hundred seven children (612 girls and 595 boys; mean age 7.3 years) were screened by self-administered questionnaires. According to answers, subjects were divided into three groups: nonsnorers (NS), occasional snorers (OS), and habitual snorers (HS). All HS, who also failed an oximetry study at home, underwent polysomnographic monitoring for the definition of SDB. BMI was calculated according to Italian growth charts.

RESULTS

A total of 809 subjects (67.0%) were eligible for the study. Of them, 44 subjects (5.4%) were classified as HS, 138 (17.0%) as OS, and 627 (77.5%) as NS. Fourteen subjects (1.7%) were given a diagnosis of obstructive sleep apnea syndrome (OSAS). Sixty-four subjects (7.9%) were defined as obese, 121 (14.9%) as overweight, and 624 (77.2%) as normal weight. The frequency of HS was significantly higher in obese subjects than in overweight and normal-weight subjects (12.5% vs 5.8% vs 4.6%, respectively; P = .02), whereas the frequency of OSAS was 1.6% in normal-weight, 1.6% in overweight, and 3.1% in obese subjects (P = not significant).

CONCLUSIONS

Our findings in a large sample of Italian children suggest that obesity is associated with snoring.