Adiposity in relation to age as predictor of severity of sleep apnea in children with snoring

Obesity, body fat distribution and eye diseases

BACKGROUND

The prevalence of obesity, a chronic disease, is increasing, and obesity is now considered a global epidemic. Eye diseases are also increasing worldwide and have serious repercussions on quality of life as well as increasingly high costs for the community. The relationships between obesity and ocular pathologies are not yet well clarified and are not pathologically homogeneous: they seem to be somehow linked to excess body fat, especially to the distribution of adipose tissue and its ectopic deposits.

PURPOSE

Our objective was to examine the associations between obesity and anthropometric indices, including body mass index (BMI), waist circumference (WC), and the waist/hip ratio (WHR), and the risk of most widespread eye diseases, with particular attention given to the most significant metabolic mechanisms.

METHODS

This article provides a narrative overview of the effect of obesity and anthropometric measurements of body fat on prevalent eye diseases. We used the MEDLINE/PubMed, CINAHL, EMBASE, and Cochrane Library databases from 1984 to 2024. In addition, we hand-searched references from the retrieved articles and explored a number of related websites. A total of 153 publications were considered.

RESULTS

There is significant evidence that obesity is associated with several eye diseases. Waist circumference (WC) and the waist/hip ratio (WHR) have been observed to have stronger positive associations with eye diseases than BMI.

CONCLUSIONS

Obesity must be considered a significant risk factor for eye diseases; hence, a multidisciplinary and multidimensional approach to treating obesity, which also affects ocular health, is important. In the prevention and treatment of eye diseases related to obesity, lifestyle factors, especially diet and physical activity, as well as weight changes, both weight loss and weight gain, should not be overlooked.

LEVEL OF EVIDENCE

Level V narrative review.

Analysis of possible risk factors for the severity of paediatric obstructive sleep apnoea syndrome

PURPOSE

This study aimed to determine the effect of body mass index (BMI) percentile, asthma, sex, and age on the paediatric obstructive sleep apnoea (OSA) severity. Furthermore, to determine the possible predictive role of the BMI percentile and age in severe OSA.

METHODS

This retrospective study included 921 children aged 2-18 years diagnosed with OSA by polysomnography. Analysis of Covariance (ANCOVA), Spearman's correlation, Receiver Operating Characteristics (ROC) analyses were performed and area under the curve (AUC) was determined.

RESULTS

We observed a significant association between a higher BMI percentile and the severity of OSA (p < 0.001, ρ = 0.15). The correlation also was significant under (p = 0.007, ρ = 0.11) and over 7 (p = 0.0002, ρ = 0.23) years of age. There was no association between the severity of OSA and the presence of asthma (p = 0.9) or sex (p = 0.891), respectively. Age was significantly related to OSA severity (p = 0.01, ρ = 0.08). Although both the BMI percentile (0.59 AUC [0.54-0.65]) and age (0.58 AUC [0.52-0.63]) predicted severe OSA, according to the sensitivity and specificity values of the ROC curve, the association presents a slight clinical relevance.

CONCLUSIONS

OSA severity is determined by the BMI percentile and age in children; however, these factors are unsuitable for predicting severe OSA in clinical practice. Based on our results, obesity is also a significant risk factor for OSA in younger children. Our study highlights that older, overweight, and obese children have a higher risk for severe OSA.

Gut microbiota dysbiosis in 4- to 6-year-old children with obstructive sleep apnea-hypopnea syndrome

OBJECTIVE

Several experiments on animals have reported the relationship between obstructive sleep apnea-hypopnea syndrome (OSAHS) and gut microbiota. We investigated the gut microbiota composition of children aged 4-6 years with OSAHS to complement the pathogenesis and clinical screening methods of OSAHS.

METHODS

We collected feces from 43 children with OSAHS and 45 controls aged 4-6 years. We extracted total bacterial DNA from feces and analyzed the composition of gut microbiota through 16S ribosomal RNA sequencing.

RESULTS

There were significant differences in bacteria producing short-chain fatty acids (SCFAs) between OSAHS children and controls, including Faecalibacterium, Roseburia, and a member of Ruminococcaceae. A gut microbiota model for pediatric OSAHS screening showed that the receiver operating characteristic-area under the curve (ROC-AUC) was 0.794 with 79.1% and 80.0% sensitivity and specificity, respectively. Functional analysis of the gut microbiota revealed several alterations in metabolism.

CONCLUSION

The composition of gut microbiota in OSAHS children is partially changed. The altered intestinal flora may provide a new screening method for the diagnosis of children with OSAHS. The prediction of gut microbiota function suggests that intestinal metabolic function may be altered in OSAHS children.

Correlation of cephalometric variables with obstructive sleep apnea severity among children: a hierarchical regression analysis

OBJECTIVE

To evaluate the correlation between cephalometric parameters and apnea-hypopnea index (AHI) after controlling gender, body mass index (BMI), and adenoid size in children with obstructive sleep apnea (OSA).

METHODS

Sixty-four children with OSA (40 males, 24 females, 8.72 ± 0.899 years) were chosen by simple random sampling for a cross-sectional study from January 2018 to March 2022. They were diagnosed with OSA, assessed by Obstructive Sleep Apnea-18 questionnaire and home polysomnography and underwent lateral cephalograms.

RESULTS

Hierarchical regression analysis indicated that cephalometric parameters (except adenoid size) were associated with OSA severity, explaining 18.1% of the AHI variance. Among cephalometric measurements, AHI was positively associated with H-RGn and N-Go-Me angle (p < 0.05) and negatively associated with NP (p < 0.05).

CONCLUSION

The sagittal diameter of the oropharynx, lower gonial angle, and hyoid position are significant AHI predictors in children with OSA, independent of demographic characteristics and adenoid size.

The 3% Oxygen Desaturation Index is an Independent Risk Factor for Hypertension Among Children with Obstructive Sleep Apnea

BACKGROUND

Obstructive sleep apnea (OSA) and obesity are both directional risk factors of hypertension. Chronic intermittent hypoxemia (IH) is a commonly observed pathophysiological mechanism involved in multiple comorbidities of OSA. However, their interactions are not well understood in children. This study aimed to investigate the associations of IH indexes (oxygen desaturation index 3% [ODI3], mean peripheral oxygen saturation [SpO₂], least SpO₂, and time with SpO₂ < 85%), apnea-hypopnea index, and weight status with hypertension in a sample of pediatric OSA patients.

METHODS

The medical records of 365 pediatric OSA patients were retrospectively reviewed in this cross-sectional study. Demographics, anthropometrics, standard in-laboratory polysomnography, and nocturnal blood pressure were collected. Multivariate logistic regression with forward selection was used to identify independent predictors of hypertension.

RESULTS

Multivariate logistic regression analysis showed that ODI3 (odds ratio [OR] = 1.02, 95% confidence interval [CI] = 1.01-1.03) and body mass index z-score (OR = 1.34, 95% CI = 1.12-1.60) were independent continuous predictors of pediatric hypertension, whilst severe OSA (OR = 2.62, 95% CI = 1.60-4.29) and overweight/obesity (OR = 2.63, 95% CI = 1.59-4.34) were independent categorical predictors. Traditional risk factors including male sex (OR = 2.33, 95% CI = 1.02-5.33), late childhood/adolescence (OR = 1.98, 95% CI = 1.01-3.88), and overweight/obesity (OR = 2.97, 95% CI = 1.56-5.67) combined with sleep hypoxemia (least SpO₂ ≤ 95%) (OR = 2.24, 95% CI = 1.16-4.04) predicted hypertension (R ² = 0.21) in the severe IH subgroup (n = 205), while the no/mild IH subgroup (n = 160) had an entirely different predictor, severe OSA (OR = 3.81, 95% CI = 1.49-9.74) (R ² = 0.07).

CONCLUSION

The close relationships among IH, overweight/obesity, and hypertension highlight the importance of reducing IH and body weight in children with OSA.

Sleep-Disordered Breathing and Cardiovascular Disease in Children and Adolescents: A Scientific Statement From the American Heart Association

Obstructive sleep apnea (OSA) is a known risk factor for cardiovascular disease in adults. It is associated with incident systemic hypertension, arrhythmia, stroke, coronary artery disease, and heart failure. OSA is common in children and adolescents, but there has been less focus on OSA as a primary risk factor for cardiovascular disease in children and adolescents. This scientific statement summarizes what is known regarding the impact of sleep‐disordered breathing and, in particular, OSA on the cardiovascular health of children and adolescents. This statement highlights what is known regarding the impact of OSA on the risk for hypertension, arrhythmia, abnormal ventricular morphology, impaired ventricular contractility, and elevated right heart pressure among children and adolescents. This scientific statement also summarizes current best practices for the diagnosis and evaluation of cardiovascular disease–related complications of OSA in children and adolescents with sleep apnea and highlights potential future research in the area of sleep‐disordered breathing and cardiovascular health during childhood and adolescence.

Correlation between craniofacial structures, anthropometric measurements, and nasopharyngeal dimensions in black adolescents

OBJECTIVES

To evaluate the correlation between craniofacial structures, anthropometric measurements, and bony and soft tissue nasopharyngeal dimensions in African Black adolescents.

METHODS

This retrospective cross-sectional study was conducted on 483 healthy adolescents (250 females and 233 males), randomly selected from one dental clinic. The inclusion criteria were skeletal and dental Class I, Black ethnicity, pubertal growth period as determined by the Greulich and Pyle atlas criteria, and no history of orthodontic treatment. Anthropometric measurements (stature, upper body height, lower body height, and BMI) and radiographic records (hand-wrist radiographs, and lateral cephalograms) were obtained. One investigator traced and analysed all cephalograms to determine three skeletal craniofacial parameters (maxillary length [Ar- ANS], mandibular length [Ar-Gn], and lower anterior facial height [ANS-Me]), and 14 (8 skeletal and 6 soft tissue) nasopharyngeal parameters. Pearson correlation coefficients and stepwise multiple linear regression analyses were conducted.

RESULTS

The mean skeletal ages of females and males were 11.31±2.31y and 12.66±1.85y, respectively. Multiple linear regression analyses showed that stature, posterior height of nasal cavity (S-PNS), length of nasal floor (AA-PNS), and mean area of bony nasopharynx (Area 1) were significantly correlated with maxillary length, P<.001. Stature, BMI, S-PNS, vertical angle of nasopharynx (Ba-S-PNS), Area 1, adenoid height (AD), and linear hyoid bone measurements (H-AA, H-RGN, H-Ax) were all correlated with mandibular length, P<.05. Lower facial height showed sexual dimorphism and was significantly associated with vertical nasopharyngeal measurements, BMI and upper body height.

CONCLUSIONS

Craniofacial structures were significantly associated with stature and upper body height. Maxillary growth was associated with bony nasopharyngeal variables. Mandibular growth and lower facial height were associated with bony and soft tissue nasopharyngeal variables. The sexual dimorphism in lower facial height warrants future studies to fully understand and manage the craniofacial complex and nasopharyngeal airway in African Black adolescents.

Advanced interdisciplinary treatment protocol for pediatric obstructive sleep apnea including medical, surgical, and orthodontic care: a narrative review

OBJECTIVE

To suggest an updated interdisciplinary treatment protocol for pediatric obstructive sleep apnea (POSA) based on the integration of craniofacial growth modification into medical and surgical sleep practice.

METHODS

PubMed, Scopus, and Cochrane library were searched up to February 2020 using keywords. Among 184 articles, 80 studies were finally included. An integrated treatment protocol for POSA encompassing craniofacial skeletal management as well as medical and surgical care was attempted.

RESULTS

A differential diagnostic workflow for identifying the phenotype of POSA was suggested, and a phenotype-based treatment protocol for POSA was proposed. Despite the lack of high level of evidence, timely skeletal growth modification in three dimensions using craniofacial growth potential could be valuable treatment for upper airway development in POSA patients with craniofacial phenotypic cause.

CONCLUSION

A novel precision treatment protocol will advance clinicians to determine the primary option or to apply the combined strategy for POSA patients.

Bariatric and metabolic surgery during and after the COVID-19 pandemic: DSS recommendations for management of surgical candidates and postoperative patients and prioritisation of access to surgery

The coronavirus disease 2019 pandemic is wreaking havoc on society, especially health-care systems, including disrupting bariatric and metabolic surgery. The current limitations on accessibility to non-urgent care undermine postoperative monitoring of patients who have undergone such operations. Furthermore, like most elective surgery, new bariatric and metabolic procedures are being postponed worldwide during the pandemic. When the outbreak abates, a backlog of people seeking these operations will exist. Hence, surgical candidates face prolonged delays of beneficial treatment. Because of the progressive nature of obesity and diabetes, delaying surgery increases risks for morbidity and mortality, thus requiring strategies to mitigate harm. The risk of harm, however, varies among patients, depending on the type and severity of their comorbidities. A triaging strategy is therefore needed. The traditional weight-centric patient-selection criteria do not favour cases based on actual clinical needs. In this Personal View, experts from the Diabetes Surgery Summit consensus conference series provide guidance for the management of patients while surgery is delayed and for postoperative surveillance. We also offer a strategy to prioritise bariatric and metabolic surgery candidates on the basis of the diseases that are most likely to be ameliorated postoperatively. Although our system will be particularly germane in the immediate future, it also provides a framework for long-term clinically meaningful prioritisation.

Risk factors of obstructive sleep apnea syndrome in children

Background

The known risk factors of childhood OSAS include tonsillar and adenoidhypertrophy, obesity, craniofacial anomalies, neuromuscular disorders and African-American (AA) ancestry. Whether other factors such as allergic rhinitis (AR), premature, environmental tobacco smoking (ETS) are associated with OSAS are inconsistent in different studies. Our study enrolled children of a broad age range and included potential risk factors of OSAS derived from previous studies and our own experience. Our objective is to identify risk factors of OSAS in children in a clinical setting.

Methods

Children between 2 and 15 years of age exhibiting snoring symptoms who visited the sleep center for polysomnography (PSG) were enrolled. All children completed a questionnaire, physical examination and PSG. The questionnaire included demographic data and information related to potential risk factors for sleep disorders. A physical examination included measurements of height, weight, neck circumference, waist and hip ratio, visual evaluation of the tonsils and the degree of adenoid obstruction. Children with obstructive apnea-hypopnea index (OAHI) ≥ 1 were defined as OSAS.

Results

A total of 1578 children were enrolled and1009 children exhibited OSAS. Univariate analyses showed that snoring occurring for ≥ 3 months, male gender, preterm birth, breastfeeding, obesity, neck circumference ≥ 30 cm, waist/hip ratio ≥ 0.95, tonsillar hypertrophy, and adenoid hypertrophy were associated with OSAS. The proportion of low educational level was higher in parents who breastfed their babies than those who didn’t. Multivariate analysis showed that snoring for ≥ 3 months, male gender, obesity, breastfeeding, tonsillar hypertrophy, and adenoid hypertrophy were associated with OSAS. Confounders such as socioeconomic status, parental occupation, and health-related behaviors should be explored further to investigate the relationship between breastfeeding and OSAS.

Conclusion

The independent risk factors for OSAS in children included snoring ≥ 3 months, male gender, obesity, breastfeeding, tonsillar and adenoid hypertrophy.

The study was registered on Clinical Trials government (NCT02447614). The name of the trial is “Follow-up Studies of Primary Snoring (PS) and Obstructive Sleep Apnea Hypopnea Syndrome (OSAHS) in Chinese Children” and the URL is https://clinicaltrials.gov/.

Relationships Among and Predictive Values of Obesity, Inflammation Markers, and Disease Severity in Pediatric Patients with Obstructive Sleep Apnea Before and After Adenotonsillectomy

Both obstructive sleep apnea (OSA) and obesity are major health issues that contribute to increased systemic inflammation in children. To date, adenotonsillectomy (AT) is still the first-line treatment for childhood OSA. However, the relationships among and predictive values of obesity, inflammation, and OSA severity have not been comprehensively investigated. This prospective study investigated body mass index (BMI), serum inflammatory markers, and OSA severity before and after AT in 60 pediatric patients with OSA. At baseline, differences in levels of interleukin-6, interleukin-9, basic fibroblast growth factor, platelet-derived growth factor-BB, as well as regulated on activation, normal T cell expressed and secreted (RANTES) were significant among the various weight status and OSA severity subgroups. After 3 months postoperatively, the differences in these inflammatory markers diminished along with a decrease in OSA severity while obesity persisted. The rate of surgical cure (defined as postoperative obstructive apnea-hypopnea index < 2.0 and obstructive apnea index < 1.0) was 62%. Multivariate analysis revealed that age, BMI z-score, granulocyte-macrophage colony-stimulating factor, monocyte chemotactic protein-1, and RANTES independently predicted surgical cure. Despite the significant reductions in inflammatory markers and OSA severity after AT, an inter-dependent relationship between obesity and OSA persisted. In addition to age and BMI, several inflammatory markers helped to precisely predict surgical cure.

Associations among sleep symptoms, physical examination, and polysomnographic findings in children with obstructive sleep apnea

PURPOSE

The relationships among PSG findings, OSA symptoms, and tonsil and adenoid size are not clear. In this study, we aimed to investigate the associations between pediatric OSA and tonsil and adenoid size using subjective (OSA-18 questionnaire) and objective (PSG) measurements.

METHODS

101 consecutive patients aged from 2 to 12 years (mean age, 5.4 ± 2.2 years; boys, 72.3%) diagnosed with OSA were enrolled in two age groups (2-6 years group and 7-12 years group) and underwent PSG and lateral cephalometric radiography. Tonsil size and the adenoid-nasopharyngeal (A/N) ratio were determined. Quality of life and sleep symptoms were measured using the Chinese version OSA-18 questionnaire. Demographic and clinical data were obtained.

RESULTS

75 and 26 patients were separately enrolled in 2-6 years group and 7-12 years group. In 2-6 years group, the multiple linear regression revealed that tonsil size and A/N ratio were associated with log apnea-hypopnea index (AHI), and the Spearman's rank correlation reflected a positive correlation between log AHI and the OSA-18 sleep disturbance score (r = 0.362, P = 0.001). Log OSA-18 score was correlated with tonsil size (r = 0.349, P = 0.002) but not the A/N ratio in 2-6 years group. Finally, no significant associations were observed between log OSA-18 scores and log AHI in all patients.

CONCLUSION

As PSG stays the golden standard for diagnoses of pediatric OSA, physical examinations and quality-of-life assessments are needed to fully assess the impact of OSA on children.

Sleep disorders in obese children are not limited to obstructive sleep apnoea syndrome

AIM

This study was to characterise respiratory and nonrespiratory sleep disorders in obese children and evaluate the diagnostic and therapeutic impact of a specific sleep consultation.

METHODS

A descriptive study was conducted in obese French children who received multidisciplinary care management from the hospital centre for paediatric obesity in Bordeaux. This followed a specific sleep consultation between 2007 and 2015, because their paediatrician had identified symptoms suggestive of sleep disorders.

RESULTS

The sleep specialist confirmed the presence of a sleep disorder in 98.4% of the 128 obese children, with a mean age of 12.1 ± 3.2 years. These included respiratory sleep disorders, hypersomnolence, insomnia and circadian rhythm sleep-wake disorders. Polysomnography revealed that 46.1% had respiratory sleep disorders and 24.2% had obstructive sleep apnoea syndrome (OSAS). Just under half (47.6%) were referred to an otorhinolaryngologist for sleep care management, 30.5% were referred to an orthodontist, 17.9% had melatonin treatment and 13.3% received continuous positive airway pressure ventilation.

CONCLUSION

Sleep disorders in obese children were not limited to respiratory sleep disorders including OSAS. A systematic specific consultation with a sleep specialist is essential for the diagnosis and care of such children and would be beneficial when treating paediatric obesity.

Morbidity and mortality associated with obesity

Obesity and its repercussions constitute an important source of morbidity, impaired quality of life and its complications can have a major bearing on life expectancy. The present article summarizes the most important co-morbidities of obesity and their prevalence. Furthermore, it describes classification and grading systems that can be used to assess the individual and combined impact of co-morbid conditions on mortality risk. The literature was screened for assessment tools that can be deployed in the quantification of morbidity and mortality risk in individual patients. Thirteen specific domains have been identified that account for morbidity and mortality in obesity. Cardiovascular disease (CVD) and cancer account for the greatest mortality risk associated with obesity. The King's Criteria and Edmonton Obesity Staging System (EOSS) were identified as useful tools for the detection and monitoring of individual patient mortality risk in obesity care. The stark facts on the complications of obesity should be capitalized on to improve patient management and knowledge and referred to in the wider dissemination of public health messages aimed at improving primary prevention.

Clinicals And Upper Airway Characteristics in Obese Children with Obstructive Sleep Apnea

Introduction

Obesity is a factor that is strongly related to the occurrence of obstructive sleep apnea (OSA) in adults, although this association remains controversial for children.

Objective

The aim of this study was to compare the clinical and upper airway charactheristics, obtained by questionnaires, physical examination and laboratory tests, among obese children with and without OSA.

Method

This was aprospective cohort study. 44 obese children (body mass index above the 95th percentile) were included in the study. Questionnaires, physical examination of the upper airway, nasofibrolaryngoscopy, polysomnography, and laboratory allergic tests were performed.

Results

There were 22 male patients (50%), and the mean age was 7.6±2.5 years. OSA was present in 19 (43%) patients. There were no statistically significant differences between the groups with and without OSA, in relation to clinical or laboratory allergic parameters. For the upper airway assessments, hypertrophy of the pharyngeal (p=0.001) and palatine (p=0.049) tonsils were the only parameters associated with OSA, and a modified Mallampati index of class III/IV also demonstrated a tendency towards being statistically associated with OSA (p=0.081). Moreover, these findings were confirmed to be factors associated with OSA in this group of children according to a logistic regression analysis.

Conclusions

The occurrence rate of OSA in this obese pediatric population was high. Adenotonsillar hypertrophy and a modified Mallampati index of class III/IV were the factors associated with OSA.

Childhood obesity patterns and relation to middle-age sleep apnoea risk: the Bogalusa Heart Study

BACKGROUND

Obese adults have a higher risk of obstructive sleep apnoea (OSA); however, the relationship between childhood obesity and adult OSA risk is unclear. Objectives This study aimed to examine overweight/obesity (OW) in childhood and risk of OSA in middle age.

METHODS

Childhood OW status was classified as never OW, weight cycling, persistent OW and incident OW. After 35 years of follow-up, high risk for OSA was determined by a positive score in ≥2 domains on the Berlin Questionnaire with obesity removed from scoring.

RESULTS

At initial assessment, mean (SD) age was 9.9 (2.9) years, and 23.9% were OW. Overall, 25.7% had scores indicating a high risk for OSA. Compared with participants who were never OW, those with persistent OW and incident OW were 1.36 (95%CI: 1.04-1.77) and 1.47 (1.11-1.96) times more likely to be high risk for OSA, after adjustment for multiple risk factors and adult OW status. Participants with an OW duration of 1-4 years, 5-8 years, and 8+ years were 0.96 (0.44-2.09), 1.20 (0.70-2.04) and 1.52 (1.22-1.90) times more likely to be high risk for OSA compared with those who were never OW (P for trend: 0.0002).

CONCLUSIONS

These results suggest that childhood OW is associated with a high risk of OSA in middle age.

Role of sleep quality in the metabolic syndrome

Emerging evidence has assigned an important role to sleep as a modulator of metabolic homeostasis. The impact of variations in sleep duration, sleep-disordered breathing, and chronotype to cardiometabolic function encompasses a wide array of perturbations spanning from obesity, insulin resistance, type 2 diabetes, the metabolic syndrome, and cardiovascular disease risk and mortality in both adults and children. Here, we critically and extensively review the published literature on such important issues and provide a comprehensive overview of the most salient pathophysiologic pathways underlying the links between sleep, sleep disorders, and cardiometabolic functioning.

Obstructive Sleep Apnea

Introduction

The severity of obstructive sleep apnea in children determines perioperative management and is an indication for postoperative polysomnography. The relationship between increasing weight and sleep apnea severity in children remains unclear.

Objectives

To compare demographic, clinical, and polysomnography parameters in normal-weight, overweight, obese, and morbidly obese children, as well as identify demographic factors that predict sleep apnea severity.

Study Design

Case series with chart review.

Setting

Academic children’s hospital.

Methods

A retrospective chart review of 290 children aged 2 to 18 years who underwent polysomnography at an academic children’s hospital was performed. Demographics, clinical findings, and polysomnographic parameters were recorded. Children were categorized as normal weight, overweight, obese, or morbidly obese. Differences were assessed using linear and logistical regression models. Significance was set at P < .05.

Results

Morbidly obese were older than normal-weight children (mean, 8.0 ± 0.5 years vs 5.8 ± 0.3 years; P < .001) and less likely to have a normal polysomnogram (16% vs 48%; P = .02). There were no differences in sex, ethnicity, birth status (term or preterm), or tonsil size between normal-weight, overweight, obese, and morbidly obese children. Sleep efficiency and percentage of time in rapid eye movement were decreased in morbidly obese compared with other children ( P < .05). The apnea-hypopnea index was positively correlated with increasing body mass index z score only as a function of increasing age ( P < .001).

Conclusion

Obstructive sleep apnea severity is correlated with a combination of increasing age and weight but not with either variable independently. This study suggests that obese and morbidly obese older children are most likely to have severe obstructive sleep apnea.

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.

Inflammatory markers and obstructive sleep apnea in obese children: the NANOS study

Introduction. Obesity and obstructive sleep apnea syndrome (OSA) are common coexisting conditions associated with a chronic low-grade inflammatory state underlying some of the cognitive, metabolic, and cardiovascular morbidities. Aim. To examine the levels of inflammatory markers in obese community-dwelling children with OSA, as compared to no-OSA, and their association with clinical and polysomnographic (PSG) variables. Methods. In this cross-sectional, prospective multicenter study, healthy obese Spanish children (ages 4–15 years) were randomly selected and underwent nocturnal PSG followed by a morning fasting blood draw. Plasma samples were assayed for multiple inflammatory markers. Results. 204 children were enrolled in the study; 75 had OSA, defined by an obstructive respiratory disturbance index (RDI) of 3 events/hour total sleep time (TST). BMI, gender, and age were similar in OSA and no-OSA children. Monocyte chemoattractant protein-1 (MCP-1) and plasminogen activator inhibitor-1 (PAI-1) levels were significantly higher in OSA children, with interleukin-6 concentrations being higher in moderate-severe OSA (i.e., AHI > 5/hrTST; P < 0.01), while MCP-1 levels were associated with more prolonged nocturnal hypercapnia (P < 0.001). Conclusion. IL-6, MCP-1, and PAI-1 are altered in the context of OSA among community-based obese children further reinforcing the proinflammatory effects of sleep disorders such as OSA. This trial is registered with ClinicalTrials.gov NCT01322763.

Obstructive sleep apnea in children is associated with severity-dependent deterioration in overnight endothelial function

BACKGROUND

Restorative sleep is expected to promote improved endothelial function (EF) in the morning compared to the evening. However, in adults with obstructive sleep apnea (OSA) EF is not only adversely affected, but it worsens during the night. Data in pediatric OSA are scarce, and overnight changes have not been explored. Therefore, we sought to examine potential associations between pediatric OSA and overnight changes in EF.

METHODS

59 habitually snoring children with various degrees of sleep-disordered breathing (age range, 4-16 years) underwent EF assessment (reactive hyperemia test by EndoPAT, Itamar Medical, Israel) in the evening before and the morning after an overnight polysomnography (PSG). Two brachial occlusion periods (1 min and 5 min) also were tested. Potential associations between evening-to-morning changes in EF and polysomnographic parameters were explored.

RESULTS

Evening-to-morning changes in children with OSA displayed severity-dependent deterioration of EF, and occlusions lasting 1 or 5 min during the reactive hyperemia test yielded similar findings.

CONCLUSIONS

In children deterioration in EF during the night significantly correlated with the severity of OSA. Furthermore, the reactive hyperemia test can be reliably performed with only 60 seconds of arterial flow occlusion in children. These findings support our hypothesis that similarly to adults, sleep apnea in children results in endothelial dysfunction (ED). We speculate that pediatric OSA is less commonly associated with cardiovascular complications possibly due to the shorter duration of the syndrome.

Treatment outcomes and compliance according to obesity in patients with obstructive sleep apnea

The objective of this study was to assess treatment outcomes and compliance according to obesity among groups of patients with obstructive sleep apnea (OSA) receiving different treatments. A total of 297 patients with OSA treated between 2006 and 2009 underwent pre- and post-treatment polysomnography. One hundred and fifty-one patients were treated with continuous airway positive pressure (CPAP), 76 with mandible advancement device (MAD), and 70 with oropharyngeal surgery. All patients were classified according to obesity. Treatment success rate and compliance of CPAP were analyzed according to obesity. For each treatment modality, the overall treatment success rate was not significantly different between obese and non-obese patients. However, the oxygen desaturation index was different in patients who were treated with MAD and surgery. Additionally, obese patients with severe OSA showed an unfavorable response to CPAP treatment. For CPAP compliance, obese patients showed a tendency to be highly compliant with CPAP treatment at 12 months than non-obese patients. This study showed that obesity might be a factor in determining the success or failure of treatment. Additionally, obesity may be a predictive factor to determine CPAP compliance.

Abdominal adiposity correlates with adenotonsillectomy outcome in obese adolescents with severe obstructive sleep apnea

Background. Obese adolescents with Obstructive Sleep Apnea (OSA) have a unique pathophysiology that combines adenotonsillar hypertrophy and increased visceral fat distribution. We hypothesized that in this population waist circumference (WC), as a clinical marker of abdominal fat distribution, correlates with the likelihood of response to AT. Methods. We conducted a retrospective cohort study of obese adolescents (BMI ≥ 97th percentile) that underwent AT for therapy of severe OSA (n = 21). We contrasted WC and covariates in a group of subjects that had complete resolution of severe OSA after AT (n = 7) with those obtained in subjects with residual OSA after AT (n = 14). Multivariate linear and logistic models were built to control possible confounders. Results. WC correlated negatively with a positive AT response in young adolescents and the percentage of improvement in obstructive apnea-hypopnea index (OAHI) after AT (P ≤ 0.01). Extended multivariate analysis demonstrated that the link between WC and AT response was independent of demographic variables, OSA severity, clinical upper airway assessment, obesity severity (BMI), and neck circumference (NC). Conclusion. The results suggest that in obese adolescents, abdominal fat distribution determined by WC may be a useful clinical predictor for residual OSA after AT.

Ventilatory responses to hypercapnia during wakefulness and sleep in obese adolescents with and without obstructive sleep apnea syndrome

STUDY OBJECTIVES

Abnormal ventilatory drive may contribute to the pathophysiology of the childhood obstructive sleep apnea syndrome (OSAS). Concomitant with the obesity epidemic, more adolescents are developing OSAS. However, few studies have specifically evaluated the obese adolescent group. The authors hypothesized that obese adolescents with OSAS would have a blunted hypercapnic ventilatory response (HCVR) while awake and blunted ventilatory responses to carbon dioxide (CO(2)) during sleep compared with obese and lean adolescents without OSAS.

DESIGN

CVR was measured during wakefulness. During nonrapid eye movement (NREM) and rapid eye movement (REM) sleep, respiratory parameters and genioglossal electromyogram were measured during CO(2) administration in comparison with room air in obese adolescents with OSAS, obese control study participants, and lean control study participants.

SETTING

Sleep laboratory.

PARTICIPANTS

Twenty-eight obese patients with OSAS, 21 obese control study participants, and 37 lean control study participants.

RESULTS

The obese OSAS and obese control groups had a higher HCVR compared with the lean control group during wakefulness. During both sleep states, all 3 groups had a response to CO(2); however, the obese OSAS group had lower percentage changes in minute ventilation, inspiratory flow, inspiratory time, and tidal volume compared with the 2 control groups. There were no significance differences in genioglossal activity between groups.

CONCLUSIONS

HCVR during wakefulness is increased in obese adolescents. Obese adolescents with OSAS have blunted ventilatory responses to CO(2) during sleep and do not have a compensatory prolongation of inspiratory time, despite having normal CO(2) responsivity during wakefulness. Central drive may play a greater role than upper airway neuromotor tone in adapting to hypercapnia.

The Endothelium as a Target in Pediatric OSA

Pediatric sleep disordered breathing has emerged in the last few decades as a highly prevalent condition by virtue of its major morbidities encompassing the central nervous, cardiovascular, and metabolic systems. In this context, improved understanding of the pathophysiological mechanisms underlying the cellular and organ injury and repair mechanisms, and the variance of the phenotype at any level of disease severity is all the more critical if appropriate personalized therapies are to be developed in the future. In this paper, the current evidence and hypothetical framework pointing to the endothelium as a primary cellular target for many of the morbidities of pediatric sleep apnea is reviewed, and particular emphasis on the recruitment of the endothelial cell lineage will be explored. It is hoped that this perspective will foster both expansion and acceleration of discovery efforts aiming to ultimately prevent the potentially lifelong consequences of sleep apnea during childhood.

Sleep, sleep-disordered breathing and lipid homeostasis: translational evidence from murine models and children

Impaired sleep, particularly in the context of sleep-disordered breathing (SDB), is associated with a vast array of comorbidities, including obesity. It is well known that the etiology of obesity is both complex and multifactorial. Recent trends have shown that obesity rates have risen at an alarming rate in children, and this has likely contributed to an increased prevalence of SDB in children. Like the 'chicken and the egg' hypothesis, the temporal relationship of obesity and SDB is unclear but it is speculated that these two conditions converge to promote a fundamental disruption to normal lipid homeostasis. In this review, the effect of sleep disruption and SDB on lipid homeostasis in both murine and human models will be critically examined, with the intent of demonstrating that disrupted sleep in children is itself a precursor to obesity via disordered lipid homeostasis.

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.

Morphological and functional vascular changes induced by childhood obesity

BACKGROUND

To investigate endothelial dysfunction and morphological vascular changes in childhood obesity.

METHODS

93 overweight/obese children (body mass index 26 ± 5 kg/m(2); median 26 kg/m(2); interquartile range 22-28 kg/m(2)), mean age 10.9 ± 2.7 years, underwent a check-up of total, high-density lipoprotein- and low-density lipoprotein-cholesterol, triglycerides, C-reactive protein, erythrocyte sedimentation rate, and white blood cell count, together with ultrasound measures of flow-mediated dilatation, carotid intima-media thickness, and anterior-posterior diameter of the abdominal aorta.

RESULTS

The body mass index of overweight/obese children had a statistically significant linear relationship (p < 0.05) with triglycerides, erythrocyte sedimentation rate, carotid intima-media thickness, anterior-posterior diameter of the abdominal aorta, and flow-mediated dilatation values.

CONCLUSIONS

Overweight/obese children have an initial endothelial dysfunction and vascular damage, i.e., the first stage in the development of atherosclerosis.

Endothelial dysfunction in children without hypertension: potential contributions of obesity and obstructive sleep apnea

BACKGROUND

Endothelial dysfunction can develop in the context of both obesity and obstructive sleep apnea (OSA) in children. However, the potential interactions between OSA and obesity have not been defined.

METHODS

Children who were prepubertal and nonhypertensive were recruited. Endothelial function was assessed in a morning fasted state, using a modified hyperemic test involving cuff-induced occlusion of the radial and ulnar arteries, and blood was drawn for assessment of myeloid-related protein 8/14 (MRP8/14) levels using a commercial enzyme-linked immunosorbent assay. Overnight polysomnography defined the presence of OSA or absence of OSA (NOSA) in subjects investigated for sleep-disordered breathing. Anthropometric measurements were performed to assign subjects to obese (OB) and nonobese (NOB) categories.

RESULTS

Fifty-four children with OSA who were obese and nonobese (mean age, 7.90 ± 0.26 years; mean BMI z-score, 1.70 ± 0.3; obstructive apnea-hypopnea index [OAHI], 7.36 ± 1.09) were compared with 54 children without OSA who were obese and nonobese (mean age, 8.26 ± 0.24 years; mean BMI z-score, 1.41 ± 0.18; OAHI, 0.86 ± 0.07). Of those subjects, 62.5% of the OB-OSA category, 38.7% of the OB-NOSA category, and 20.0% of the NOB-OSA category had evidence of endothelial dysfunction, compared with 0.0% of the NOB-NOSA category (P < .01). The degree of endothelial dysfunction in all groups was associated with circulating MRP8/14 levels (r = 0.343, P < .001).

CONCLUSIONS

Both obesity and OSA can independently increase the risk for endothelial dysfunction, and the concurrent presence of both markedly increases such risk. Although the mechanisms underlying endothelial dysfunction remain unclear, a potential role for MRP8/14 as an inflammatory biomarker of endothelial dysfunction is suggested.

Urinary leukotriene E4, obesity, and adenotonsillar hypertrophy in Chinese children with sleep disordered breathing

STUDY OBJECTIVES

Sleep disordered breathing (SDB) has been associated with increased inflammatory responses. Changes in the level of pro-inflammatory leukotrienes (LTs) may initiate or exacerbate pediatric SDB and may play a major role in end-organ morbidity. The objective of the study was to investigate the relationship of LT productions with severity of SDB, obesity, and adenotonsillar hypertrophy in children.

DESIGN/INTERVENTIONS

Prospective, observational study that included standard questionnaires, physical examinations, overnight polysomnography (PSG), and urinary leukotriene E(4) (LTE(4)) assay.

SETTING

Sleep Center and Laboratory of Nutriology.

PATIENTS OR PARTICIPANTS

282 children with SDB and 94 healthy control subjects were recruited.

MEASUREMENTS AND RESULTS

Urinary LTE(4) levels were elevated in children with SDB compared to the controls, and LTE(4) productions emerged disease severity- and obesity-dependent increases. In stepwise multiple regression analysis, the independent predictors of the apnea-hypopnea index (AHI) included LTE(4) level and adenotonsillar-size sum score (P < 0.001 respectively; adjusted R(2)=0.318). A positive relationship between LTE(4) urinary level and adenotonsillar-size sum scores was present in the underweight/normal weight SDB subjects (r=0.276; P < 0.001), but not in the overweight/obese children (P > 0.05).

CONCLUSIONS

Systemic inflammation mediated by LTs participates in the pathophysiological mechanisms of SDB in children. The magnitude of inflammation as reflected by urinary LTE(4) is significantly related to the severity of SDB and obesity. However, a correlation between LTE(4) concentration and adenotonsillar size is present only among nonobese children.

Obesity and obstructive sleep apnea syndrome in children: a tale of inflammatory cascades

Obesity has emerged as one of the most prevalent diseases in the western hemisphere, and its prevalence continues to increase. Obese children are at increased risk for several disorders, particularly affecting the cardiovascular and metabolic systems. The mechanisms leading to obesity-related morbidities are likely multifactorial, and include activation of inflammatory pathways ultimately leading to end-organ injury. Furthermore, the concurrent presence of obesity and other diseases facilitated by increased fat deposition poses a theoretical risk of accentuating obesity-related complications. One of the conditions whose prevalence is increased by obesity in childhood is the obstructive sleep apnea syndrome (OSAS). OSAS in non-obese children may lead to co-morbidities that are not only remarkably similar to those associated with obesity but recruit similar inflammatory mechanisms as those activated by obesity, suggesting that the two disorders may amplify each other and synergistically augment the magnitude of their respective adverse consequences. The objective of this review is to critically review the effects of both obesity and OSAS in inducing systemic inflammation in children and will examine the latest evidence pertaining to the up-regulation of specific inflammatory mediators.

Systematic Review of Pediatric Tonsil Size and Polysomnogram-Measured Obstructive Sleep Apnea Severity

Objective. Systematically review the biomedical literature for data comparing clinical, subjective tonsil size (0-4+ scale) to objectively measured obstructive sleep apnea syndrome (OSAS) using polysomnography (PSG).

Data Sources. PubMed database.

Review Methods. A comprehensive PubMed MeSH search was conducted to identify articles comparing subjective tonsil size to objectively measured OSAS. Inclusion criteria included pediatric patients only, sample size greater than 5, and sufficient data to extract for analysis. Exclusion criteria included patients with obesity or craniofacial syndromes.

Results. Twenty articles were included in the final data set. The mean sample size was 161 (range, 32-700) and grand mean age was 6.7 (range, 2.7-11.7). Case series (evidence based medicine [EBM] level 4) was the predominant study design (16 studies). Eleven of 20 studies concluded there was an association between subjective tonsil size and objective OSAS, whereas 9 did not. Varying statistical techniques were used including simple diagnostic tables (k = 8), linear or logistic regression (k = 19), correlation (k = 5), and analysis of variance (k = 2). A customized quality assessment of each study was performed. Studies showing no association between tonsil size and OSAS had a higher quality score than studies showing an association (3.22 vs 2.36, P = .0317).

Conclusion. The association between subjective pediatric tonsil size using 0-4+ scale and objective OSAS severity is weak at best. High-quality studies suggest no association. Providers must recognize the limitations of using tonsil size in clinical decision making.

Habitual snoring in school-aged children: environmental and biological predictors

Background

Habitual snoring, a prominent symptom of sleep-disordered breathing, is an important indicator for a number of health problems in children. Compared to adults, large epidemiological studies on childhood habitual snoring and associated predisposing factors are extremely scarce. The present study aimed to assess the prevalence and associated factors of habitual snoring among Chinese school-aged children.

Methods

A random sample of 20,152 children aged 5.08 to 11.99 years old participated in a cross-sectional survey, which was conducted in eight cities of China. Parent-administrated questionnaires were used to collect information on children's snoring frequency and the possible correlates.

Results

The prevalence of habitual snoring was 12.0% (14.5% for boys vs. 9.5% for girls) in our sampled children. Following factors were associated with an increased risk for habitual snoring: lower family income (adjusted odds ratio [OR] = 1.46), lower father's education (OR = 1.38 and 1.14 for middle school or under and high school of educational level, respectively), breastfeeding duration < 6 months (OR = 1.17), pregnancy maternal smoking (OR = 1.51), obesity (OR = 1.50), overweight (OR = 1.35), several respiratory problems associated with atopy and infection, such as chronic/allergic rhinitis (OR = 1.94), asthma (OR = 1.43), adenotonsillar hypertrophy (OR = 2.17), and chronic otitis media (OR = 1.31), and family history of habitual snoring (OR = 1.70).

Conclusion

The prevalence of habitual snoring in Chinese children was similar to that observed in other countries. The potential predisposing factors covered socioeconomic characteristics, environmental exposures, chronic health problems, and family susceptibility. Compared to socioeconomic status and family susceptibility, environmental exposures and chronic health problems had greater impact, indicating childhood habitual snoring could be partly prevented by health promotion and environmental intervention.

Palatine tonsil size in obese, overweight, and normal-weight children with sleep-disordered breathing

Objective: To assess palatine tonsil size relative to degree of obesity in children with sleep-disordered breathing (SDB).

Study Design: Case-control study.

Setting: Tertiary care rhinology clinic.

Subjects and Methods: We compared the subjective and objective tonsil size, including tonsil height (TH), tonsil width (TW), tonsil thickness (TT), tonsil weight (TWt), and tonsil volume (TV), in 26 obese children and 26 age- and gender-matched control children with SDB, and in 29 overweight children and 29 matched controls with SDB.

Results: Despite similar subjective tonsil size in obese and control children, the objective tonsil size, including TH, TW, TT, and TWt, was larger in obese than in control children, and the mean TV was significantly greater in obese than in control children with SDB (8.53 ± 3.30 mL vs 6.90 ± 2.05 mL; 95% confidence interval [CI] of the difference 0.03-3.25; P = 0.019). In contrast, mean TV (7.38 ± 3.43 mL vs 7.65 ± 1.97 mL; 95% CI −1.92 to 1.37; P = 0.320) as well as the other parameters of objective palatine tonsil size, including TH, TW, TT, and TWt, did not differ significantly between overweight children and controls.

Conclusion: Obese children with SDB had larger palatine tonsils than did normal-weight children with SDB. This finding suggests that larger palatine tonsils may have a greater effect on upper airway obstruction in obese than in normal-weight children with SDB.

Associations of tonsillar hypertrophy and snoring with history of wheezing in childhood

BACKGROUND

Reports in adults and children have correlated history of wheezing or asthma with the presence of obstructive sleep-disordered breathing but the mechanism of this epidemiologic association is unknown. The goal of the present study was to examine whether tonsillar hypertophy can explain this association.

METHODS

Children were recruited from the Emergency Department and the Pediatric Pulmonology Clinic. History of wheezing requiring treatment (explanatory variable) and snoring > or = 1 night/week (outcome) were recorded and presence of tonsillar hypertrophy (outcome) was assessed.

RESULTS

Four hundred forty-two children were recruited (mean age: 7.6 + or - 3.6 years) and 210 of them had history of wheezing. History of wheezing was significantly associated with the presence of tonsillar hypertrophy and snoring even after adjustment for age, gender, obesity, and passive smoking [odds ratio (95% confidence interval): 2.23 (1.37-3.63); P = 0.001 and 1.73 (1.12-2.67); P = 0.013, respectively]. When only children with tonsillar hypertrophy were considered (n = 92), history of wheezing was significantly related to the presence of snoring, whereas in subjects without tonsillar hypertrophy (n = 350) wheezing did not affect snoring [odds ratio: 2.76 (1.10-6.93); P = 0.031 and 1.49 (0.92-2.43); P = 0.107, respectively].

CONCLUSIONS

Children with history of wheezing have more frequently tonsillar hypertrophy than those without wheezing. Tonsillar hypertrophy may mediate at least in part the reported association between asthma and obstructive sleep-disordered breathing in childhood.

Endothelial dysfunction in obese non-hypertensive children without evidence of sleep disordered breathing

BACKGROUND

Endothelial dysfunction is a complication of both obesity and obstructive sleep apnea syndrome (OSAS), the latter being highly prevalent among obese children. It is unknown whether obesity causes endothelial dysfunction in children in the absence of OSAS. This study examines endothelial function in obese and non-obese children without OSAS.

METHODS

Pre-pubertal non-hypertensive children were recruited. Endothelial function was assessed in a morning fasted state, using a modified hyperemic test involving cuff-induced occlusion of the radial and ulnar arteries. The absence of OSAS was confirmed by overnight polysomnography. Anthropometry was also performed.

RESULTS

55 obese children (mean age 8.6 +/- 1.4 years, mean BMI z-score: 2.3 +/- 0.3) were compared to 50 non-obese children (mean age 8.0 +/- 1.6 years, mean BMI z-score 0.3 +/- 0.9). Significant delays to peak capillary reperfusion after occlusion release occurred in obese compared to non-obese children (45.3 +/- 21.9 sec vs. 31.5 +/- 14.1 sec, p < 0.01), but no differences in the magnitude of hyperemia emerged. Time to peak reperfusion and percentage of body fat were positively correlated (r = 0.365, p < 0.01).

CONCLUSIONS

Our findings confirm that endothelial dysfunction occurs early in life in obese children, even in the absence of OSAS. Thus, mechanisms underlying endothelial dysfunction in pediatric obesity are operational in the absence of sleep-disordered breathing.

Tonsillar size in 2- to 14-year-old children with and without snoring

BACKGROUND

Few investigations have assessed tonsillar size in children of variable age, sleep-disordered breathing (SDB) status and degree of adiposity. This study evaluated the size of tonsils in young and older, lean and obese children, without or with snoring.

METHODS

Children attending the Emergency Department or Pulmonology Clinic were recruited and tonsillar size was scored 1-4. Snoring >or=1 night/week was considered diagnostic of SDB and body mass index z-score >or=1.645 was defined as obesity. Age was analyzed as dichotomous variable (<or=7 years old vs. >7 years old).

RESULTS

362 children (2-14 years old) were recruited; 78 (21.5%) were obese and 108 (29.8%) had SDB. SDB-but not age or obesity-was significantly related to tonsillar size (P = 0.001). There was not enough evidence to support the presence of interactions between SDB and age or obesity regarding the size of tonsils (P = 0.157 and P = 0.978, respectively). Young subjects without SDB had larger tonsils than older subjects without SDB (1.9 +/- 0.7 vs. 1.7 +/- 0.8; P = 0.017), whereas age did not affect tonsillar size in children with SDB (P = 0.78).

CONCLUSIONS

Young and older children with SDB have similar tonsillar size. In contrast, older subjects without snoring have smaller tonsils than young subjects without snoring. Tonsillar enlargement in children with SDB probably occurs in early childhood without change in older age.

Risk factors and treatment for obstructive sleep apnea amongst obese children and adults

PURPOSE OF REVIEW

The purpose of this review is to summarize the evidence for the association between obesity and obstructive sleep apnea (OSA), as well as predisposing risk factors and treatment strategies for OSA amongst obese patients.

RECENT FINDINGS

Recent findings highlight a number of factors including sex, age, upper airway structure and ethnicity, which may predispose patients to OSA when obese. Both invasive and noninvasive weight-reduction strategies also show positive signs of being an effective means to reduce or remediate OSA amongst obese adults and children.

SUMMARY

In view of recent findings, a direct association between body mass and upper airway obstruction should be viewed with caution. Obesity may play a more significant role in the predisposition to OSA amongst particular subgroups of the population, such as adults, and those with particular craniofacial and upper airway morphology. Healthcare prioritization and requirements may be more substantial for such groups. Further, commonly used treatment methods for OSA (such as adenotonsillectomy for children and continuous positive airway pressure for adults) may be less effective for obese individuals. Weight-reduction strategies appear important for an optimal outcome, and such strategies may be more or less invasive depending on the severity of obesity, OSA or both, and other patient complications.

Obstructive sleep apnea in children: relative contributions of body mass index and adenotonsillar hypertrophy

BACKGROUND

The obesity epidemic has prompted remarkable changes in the proportion of obese children who are referred for habitual snoring. However, the contribution of obesity to adenotonsillar hypertrophy remains undefined.

METHODS

In our study, 206 nonobese habitually snoring children with polysomnographically diagnosed obstructive sleep apnea (OSA) were matched for age, gender, ethnicity, and obstructive apnea-hypopnea index (OAHI) to 206 obese children. Size estimates of tonsils and adenoids, and Mallampati class scores were obtained, and allowed for the assessment of potential relationships between anatomic factors and obesity in pediatric OSA.

RESULTS

The mean OAHI for the two groups was approximately 10.0 episodes/h total sleep time. There was a modest association between adenotonsillar size and OAHI in nonobese children (r = 0.22; p < 0.001) but not in obese children. The mean (+/- SEM) adenotonsillar size was larger in nonobese children (3.85 +/- 0.16 vs 3.01 +/- 0.14, respectively; p < 0.0001), and conversely Mallampati class scores were significantly higher in obese children (p < 0.0001).

CONCLUSION

The magnitude of adenotonsillar hypertrophy required for any given magnitude of OAHI is more likely to be smaller in obese children compared to nonobese children. Increased Mallampati scores in obese children suggest that soft-tissue changes and potentially fat deposition in the upper airway may play a significant role in the global differences in tonsillar and adenoidal size among obese and nonobese children with OSA.

The effect of weight loss on sleep-disordered breathing in obese teenagers

The objective of this study was to assess the effect of weight loss on sleep-disordered breathing (SDB) in obese teenagers attending a residential treatment center. We also assessed whether the presence of SDB at the start of the weight management therapy was correlated with the amount of weight loss achieved. Obese teenagers were recruited and underwent anthropometry and sleep screening. Subjects with SDB (apnea hypopnea index (AHI)>or=2) received a follow-up screening after weight loss therapy. Sixty-one obese subjects were included (age=14.8+/-2.3; BMI z score=2.7+/-0.4). Thirty-one subjects were diagnosed with SDB with 38% continuing to have residual SDB after a median weight loss of 24.0 kg. Subjects with SDB had a higher median relative decrease in BMI z score compared to subjects without SDB which was 30.5, 33.6, and 50.4% in the group with AHI of the baseline screening study<2, 2<or=AHI<5, and AHI>or=5, respectively (P=0.02). AHI of the baseline screening study correlated significantly with the relative decrease in BMI z score (partial r=0.37; P=0.003), controlling for gender, age, initial BMI z score, and time between both studies. In conclusion, weight loss was successful in treating SDB in obese teenagers. In addition, there was a positive association between the severity of SDB at the start of the treatment and the amount of weight loss achieved. These findings are in favor of considering weight loss as a first-line treatment for SDB in obese children and adolescents.

Obesity and persisting sleep apnea after adenotonsillectomy in Greek children

BACKGROUND

The relative importance of obesity and adenotonsillar hypertrophy in the pathogenesis of obstructive sleep-disordered breathing (SDB) in childhood is unclear. Adenotonsillectomy (AT) for SDB is not always curative, and obese children are at increased risk for residual disease postoperatively.

OBJECTIVE

The aim of this investigation was to assess the efficacy of AT as treatment for SDB in obese and nonobese children.

METHODS

Children with adenoidal and/or tonsillar hypertrophy who underwent AT for the treatment of SDB underwent polysomnography preoperatively and postoperatively. A body mass index (BMI) z score of > 1.645 was used to define obesity. The achievement of a postoperative obstructive apnea-hypopnea index (OAHI) of less than one episode per hour (ie, the cure of SDB) was the primary outcome measure.

RESULTS

Twenty-two obese children (mean [+/- SD] age, 5.8 +/- 1.8 years; mean BMI z score, 2.6 +/- 0.8; mean OAHI, 9.5 +/- 9.7 episodes per hour) and 48 nonobese children (mean age, 6.9 +/- 2.6 years; mean BMI z score, 0.09 +/- 1.1; OAHI, 6 +/- 5.4 episodes per hour) were recruited. After surgery, obese and nonobese subjects did not differ in the efficacy of AT (postoperative OAHI of less than one episode per hour, 22.7% vs 25% of subjects, respectively; p > 0.05). The presence of obesity, adenoidal or tonsillar hypertrophy, gender, and postoperative BMI change were not significant predictors of SDB cure.

CONCLUSIONS

Obesity does not necessarily predict an unfavorable outcome of AT as treatment for SDB.

Absence of blood pressure, metabolic, and inflammatory marker changes after adenotonsillectomy for sleep apnea in Greek children

AIM

Pediatric studies revealed associations of obstructive sleep-disordered breathing (SDB) with inflammation, metabolic dysfunction, and elevated blood pressure. Evidence about effects of adenotonsillectomy on these abnormalities is scarce. Aim of this investigation was to assess changes in C-reactive protein (CRP), circulating intercellular adhesion molecule-1 (cICAM-1), insulin and blood pressure levels after adenotonsillectomy for SDB in Greek children.

METHODS

Polysomnography was performed pre- and postoperatively in children with SDB and controls undergoing adenotonsillectomy for recurrent tonsillitis or otitis. Outcome measures were changes in serum markers and blood pressure.

RESULTS

Fifty-eight patients (6.2 +/- 2.5 years old) and 17 controls (6.5 +/- 2) were studied. After surgery, apnea-hypopnea index (AHI) decreased (mean: -5.9 episodes/hr; 95% confidence interval: -7.8 to -4) in patients. Patients and controls were similar regarding outcomes: CRP (-0.11 mg/dl [-0.25 to 0.02] vs. 0.13 [-0.19 to 0.46]; P = 0.11), cICAM-1 (-11.6 ng/ml [-38.6 to 15.4] vs. -46.6 [-101.7 to 8.6]; P = 0.23), insulin (2.49 mU/L [0.32-4.67] vs. -0.16 [-2.47 to 2.16]; P = 0.21), systolic blood pressure index (5.2% [2.1-8.3] vs. 10.8 [3.6-17.9]; P = 0.1) and diastolic blood pressure index (-3.2% [-7.2 to 0.8] vs. 2.8 [-5.5 to 11.2]; P = 0.16). Patients with CRP > 0.3 mg/dl had reduced values after AT (P = 0.003) and those with postoperative AHI < or = 1 had a decrease in diastolic blood pressure (P = 0.02).

CONCLUSIONS

Although adenotonsillectomy improves SDB, it has variable effects on inflammatory and metabolic markers or blood pressure.

Obstructive sleep apnea in children: implications for the developing central nervous system

Recent increases in our awareness to the high prevalence of sleep disorders in general and of sleep-disordered breathing among children, in particular, has led to concentrated efforts aiming to understand the pathophysiological mechanisms, clinical manifestations, and potential consequences of such conditions. In this review, I will briefly elaborate on some of the pathogenetic elements leading to the occurrence of obstructive sleep apnea (OSA) in children, focus on the psychobehavioral consequences of pediatric OSA, and review the evidence on the potential mechanisms underlying the close association between central nervous system morbidity and the episodic hypoxia and sleep fragmentation that characterize OSA.