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Objective Hospital utilisation research is important in pursuing cost-saving healthcare models. Tonsillectomy is one of the most common paediatric surgeries and the most frequent reason for paediatric hospital readmission. This study aimed to report the government-funded costs of paediatric tonsillectomy in the state of Victoria, Australia, extrapolate costs across Australia, and identify the cost determinants. Methods A population-based longitudinal study was conducted with a bottom-up costing approach using linked datasets containing all paediatric tonsillectomy and tonsillectomy with adenoidectomy surgeries performed in the state of Victoria between 2010 and 2015. Results The total average annual cost of tonsillectomy hospitalisation in Victoria was A$21 937 155 with a median admission cost of A$2224 (interquartile range (IQR) 1826–2560). Inflation-adjusted annual tonsillectomy costs increased during 2010–2015 (P < 0.001), not explained by the rising number of surgeries. Hospital readmissions resulted in a total average annual cost of A$1 427 716, with each readmission costing approximately A$2411 (IQR 1936–2732). The most common reason for readmission was haemorrhage, which was associated with the highest total cost. The estimated total annual expenditure of both tonsillectomy and resulting readmissions across Australia was A$126 705 989. Surgical cost in the upper quartile was associated with younger age, male sex, lower socioeconomic status, surgery for reasons other than infection alone, overnight vs day case surgery, public hospitals and metropolitan hospitals. Surgery for obstructed breathing during sleep had the strongest association to high surgical cost. Conclusions This study highlights the cost of paediatric tonsillectomy and associated hospital readmissions. The study findings will inform healthcare reform and serve as a basis for strategies to optimise patient outcomes while reducing both postoperative complications and costs.

Aim: In children with Prader-Willi syndrome (PWS), growth hormone (GH) improves height and body composition; however, may be associated with worsening sleep-disordered breathing (SDB). Some studies have reported less SDB after GH initiation, but follow-up with polysomnography is still advised in most clinical guidelines. Methods: This retrospective, multicentre study, included children with PWS treated with GH at seven PWS treatment centres in Australia over the last 18 years. A paired analysis comparing polysomnographic measures of central and obstructive SDB in the same child, before and after GH initiation was performed with Wilcoxon signed-rank test. The proportion of children who developed moderate/severe obstructive sleep apnoea (OSA) was calculated with their binomial confidence intervals. Results: We included 112 patients with available paired data. The median age at start of GH was 1.9 years (range 0.1–13.5 years). Median obstructive apnoea hypopnoea index (AHI) at baseline was 0.43/h (range 0–32.9); 35% had an obstructive AHI above 1.0/h. Follow-up polysomnography within 2 years after the start of GH was available in 94 children who did not receive OSA treatment. After GH initiation, there was no change in central AHI. The median obstructive AHI did not increase significantly (P = 0.13), but 12 children (13%, CI95% 7–21%) developed moderate/severe OSA, with clinical management implications. Conclusions: Our findings of a worsening of OSA severity in 13% of children with PWS support current advice to perform polysomnography after GH initiation. Early identification of worsening OSA may prevent severe sequelae in a subgroup of children.

Prader-Willi Syndrome (PWS) is a rare genetic disorder associated with emotional/behavioral disturbances. These difficulties are well documented in the literature, but the positive attributes of these individuals are not described. Taking a strengths-based approach, the aim of this study was to describe the emotional/behavioral strengths and difficulties in children and young people with PWS from their parent caregivers' perspectives. Parent caregivers of 52 individuals with PWS aged 4-24 years (median = 12.1 years; including 22 males) completed the parent form of the Developmental Behavior Checklist (DBC-P), including its original two open-ended questions regarding positive traits. Prevalences of emotional/behavioral disturbances were comparable to those reported in previous literature: common behaviors of concern across studies being skin-picking (75%), impulsivity (69%), poor sense of danger (67%), lying (67%), and tantrums (54%). Total DBC-P scores showed that just over half (n = 28, 54%) had scores indicative of clinically significant behavior problems. However, thematic analysis of caregivers' written comments regarding their children's strengths resolved into three themes: warmth (94%), persistence (41%), and skills (41%). Warmth encompassed friendliness, happiness, and empathy. A strength-based approach to behavioral difficulties in PWS provides a more balanced view of the children and a more holistic foundation for interventions.

The goal of this position paper on ventilatory support at home for children is to provide expert consensus from Australia and New Zealand on optimal care for children requiring ventilatory support at home, both non-invasive and invasive. It was compiled by members of the Thoracic Society of Australia and New Zealand (TSANZ) and the Australasian Sleep Association (ASA). This document provides recommendations to support the development of improved services for Australian and New Zealand children who require long-term ventilatory support. Issues relevant to providers of equipment and areas of research need are highlighted.

Objectives Adherence to Continuous Positive Airway Pressure (CPAP) in children can be challenging. Advancements in CPAP technology have potential to influence adherence. The aim of this study was to compare adherence rates of children with obstructive sleep apnoea (OSA) initiated on autotitrating CPAP (APAP) with remote modem monitoring compared to a cohort started on fixed pressure CPAP alone. Methods Children aged over 3 years starting APAP at our centre between February 2017 and February 2020 were included. Therapy data was obtained for the initial 90 days. Data was compared to a cohort of children started on CPAP between July 2004 and September 2008. Results A total of 61 patients with a median age of 14.3 years formed the APAP group, and were significantly older than the CPAP group who had a median age of 8.6 years (p = 0.02). Co-morbid conditions were present in 51% compared with 69% in the earlier cohort (p = 0.11). No significant difference was found in any adherence parameters between the groups. The value closest to achieving a significant difference was hours used per day used, with an median of 5.2 h in the CPAP group compared with 7.0 h in the APAP group (p = 0.07). Two-way ANOVA including age group (above or below 13 years) showed that both age group and treatment group (CPAP vs APAP) were significantly associated with a difference in adherence (F = 4.41, p = 0.006), with mean hours used on days used being highest in the APAP group aged under 13 years. However no significant interaction was found between age and treatment group. Conclusion Despite the convenience for patients with outpatient initiation and ability to achieve optimal pressures quickly and remotely, our results show no improvement in adherence using APAP with remote monitoring, with the possible exception of children aged under 13 years. A large randomized controlled trial would be required to confirm these findings.

ObjectiveDiagnosis of obstructive sleep apnoea (OSA) is made on overnight polysomnography (PSG). Given the widespread availability of smartphone video technology, we aimed to develop and test a standardised scoring system for smartphone videos and compare these scores to PSG results.MethodsChildren aged 1–16 years undergoing PSG for suspected OSA were included. Parents were asked to take 1–2 min videos of the breathing they were concerned about. Videos were scored using a newly developed and tested tool on five components: inspiratory obstructive noises (1–4), presence of obstructive events (0–1), increased work of breathing (0–1), mouth breathing (0–1) and neck extension (0–1). Video scores and the Obstructive Apnoea Hypopnoea Index (OAHI) were compared using Spearman correlation. Sensitivity, specificity, positive predictive value and negative predictive value were calculated for different cut-off scores to achieve the best results.ResultsVideos from 43 children (28 men (65.1%), median age 5.7 years (range 2.6–14.0 years), median OAHI 3.8/hour (range 0–82 events/hour) were included. Nine children (20.9%) had a video score of 5 events/hour) .ConclusionWe have developed and validated a simple clinical tool (the Monash Obstructive Sleep Apnoea Video Score) to quantify abnormalities in breathing seen on short video recordings made on a smartphone. A low score rules out moderate–severe OSA and may be valuable in the triage of children with symptoms of OSA.

Prader-Willi syndrome (PWS) is a rare genetic disorder characterised by neurodevelopmental delays, hyperphagia, difficulties with social communication and challenging behaviours. Individuals require intensive supervision from caregivers which may negatively affect caregiver quality of life. This study used data collected in the Australasian PWS Registry (n = 50, mean age 11.2 years) to evaluate associations between child behaviours and caregiver mental well-being. Symptoms of sleep-related breathing disorder, child depression and social difficulties were associated with poorer caregiver mental and physical well-being. Growth hormone therapy use was associated with better caregiver mental and physical well-being. Optimising management of problematic behaviours and sleep disturbances have the potential to support caregivers who are the most vital network of support for individuals affected by PWS.

STUDY OBJECTIVES: Studies of sleep-disordered breathing (SDB) in children with Prader-Willi syndrome (PWS) have focused on early childhood and growth hormone (GH)–naïve children, but little is known about older children, including those on long-term GH therapy. This study aimed to describe the nature and prevalence of SDB in school-aged children with PWS in the growth hormone era. METHODS: This retrospective single-center chart review included children aged 6–18 years with PWS who had overnight polysomnography not involving respiratory support over 5 years (2012–2017). The main outcome measures were the presence of obstructive sleep apnea, central sleep apnea, or hypoventilation defined by an elevated transcutaneous partial pressure of carbon dioxide (TcPCO(2)) as per standard pediatric criteria. RESULTS: Seventeen children (8 males; median age 11.6 years, range 6.6–16.1 years) were included. Fifteen demonstrated SDB of different types: central sleep apnea (18%), obstructive sleep apnea (24%), both obstructive and central sleep apnea (29%), or hypoventilation without obstructive or central sleep apnea (18%). Twelve (71%) children had evidence of hypoventilation. Those with hypoventilation had a higher central apnea-hypopnea index but no difference in the obstructive apnea-hypopnea index, age, sex, growth parameters, or the presence of scoliosis or sleep-related symptoms compared with those without hypoventilation. CONCLUSIONS: Sleep-related hypoventilation is common in school-aged children with PWS. The presence of central sleep apnea, including the quantification of central hypopneas, but not obstructive sleep apnea or clinical factors, predicted the presence of hypoventilation. Long-term polysomnography surveillance in children with PWS should include identification of central hypopneas and measurement of continuous pCO(2). CITATION: Schaefer J, Davey MJ, Nixon GM. Sleep-disordered breathing in school-aged children with Prader-Willi syndrome. J Clin Sleep Med. 2022;18(4):1055–1061.

The concept of personalised medicine is likely to revolutionise the treatment of adult obstructive sleep apnoea as a result of recent advances in the understanding of disease heterogeneity by identifying clinical phenotypes, pathophysiological endotypes, biomarkers and treatable traits. Children with the condition show a similar level of heterogeneity and paediatric obstructive sleep apnoea would also benefit from a more targeted approach to diagnosis and management. This review aims to summarise the adult literature on the phenotypes and endotypes of obstructive sleep apnoea and assess whether a similar approach may also be suitable to guide the development of new diagnostic and management approaches for paediatric obstructive sleep apnoea.

In adults there is a distinct gender difference in the prevalence and severity of sleep disordered breathing (SDB), however there have been limited studies examining the effects of gender in children with SDB. We aimed to compare the effects of gender on severity of SDB, blood pressure, sleep and respiratory characteristics, quality of life, behavior and executive function.We included 533 children aged 3-18 years, who underwent standard pediatric overnight polysomnography (PSG) between 2004 and 2016. Blood pressure was recorded prior to each study. Quality of life, behavior and executive function were assessed with parental questionnaires. Children were grouped by gender and SDB severity based on their obstructive apnea hypopnea index (OAHI) into non-snoring controls, Primary Snoring (PS) (OAHI≤1 event/h), Mild obstructive sleep apnea (OSA) (OAHI1-≤5 events/h) and moderate/severe (MS) OSA (OAHI5 events/h) and data compared with 2-way ANOVA.A total of 298 boys and 235 girls were studied. There were no differences in age, BMI z-score, SDB severity sleep characteristics or blood pressure between genders. Diastolic blood pressure was elevated in females with MS OSA compared to males (P 0.05). Quality of life, behavior and executive function scores were all elevated in the SDB groups compared to controls. Females with MS OSA exhibited more internalizing behavioral problems compared to males (59.2 ± 2.4 vs. 51.4 ± 2.3, P 0.05).In contrast to studies in adults, we identified no gender differences in the severity or consequences of SDB in children, other than females with moderate-severe OSA exhibiting more internalizing problems and higher diastolic blood pressure.

Background Tonsillectomy, with or without adenoidectomy, is the leading reason for paediatric unplanned hospital readmission, some of which are potentially avoidable. Reducing unplanned hospital revisits would improve patient safety and decrease use of healthcare resources. This study aimed to describe the incidence, timing and risk factors for any surgery-related hospital revisits (both emergency presentation and readmission) following paediatric tonsillectomy and adenotonsillectomy in a large state-wide cohort. Methods We conducted a population-based cohort study using linked administrative datasets capturing all paediatric tonsillectomy and adenotonsillectomy surgeries performed between 2010 and 2015 in the state of Victoria, Australia. The primary outcome was presentation to the emergency department or hospital readmission within 30-day post-surgery. Results Between 2010 and 2015, 46,583 patients underwent 47,054 surgeries. There was a total of 4758 emergency department presentations (10.11% total surgeries) and 2750 readmissions (5.84% total surgeries). Haemorrhage was the most common reason for both revisit types, associated with 33.02% of ED presentations (3.34% total surgeries) and 67.93% of readmissions (3.97% total surgeries). Day 5 post-surgery was the median revisit time for both ED presentations (IQR 3–7) and readmission (IQR 3–8). Predictors of revisit included older age, public and metropolitan hospitals and peri-operative complications during surgery. Conclusions Haemorrhage was the most common reason for both emergency department presentation and hospital readmission. The higher risk of revisits associated with older children, surgeries performed in public and metropolitan hospitals, and in patients experiencing peri-operative complications, suggest the need for improved education of postoperative care for caregivers, and avoidance of inappropriate early discharge. Graphical Abstract

Individuals with Prader-Willi syndrome (PWS) often have excessive daytime sleepiness and emotional/behavioral disturbances. The objective of this study was to examine whether daytime sleepiness was associated with these emotional/behavioral problems, independent of nighttime sleep-disordered breathing, or the duration of sleep. Caregivers of individuals with PWS (aged 3 to 25 years) completed the Pediatric Sleep Questionnaire (PSQ), Epworth Sleepiness Scale for Children and Adolescents (ESS-CHAD), and the parent version of the Developmental Behavior Checklist (DBC-P). Sleep adequacy was adjusted for age by computing sleep duration against age-specific recommendations. The associations between ESS-CHAD and the total DBC and its subscale scores were evaluated by linear regression, adjusted for sleep-related breathing difficulties, sleep adequacy, and body mass index (BMI). There were 54 responses for individuals with PWS (including 22 males) aged 4.4–24.0 (mean 12.5) years. Daytime sleepiness predicted a substantial proportion of the variance in total DBC-P scores in the unadjusted model (28%; β = 0.028; p β = 0.023; p = 0.007). This relationship was not moderated by BMI Z-scores, but the relationship was more prominent for children younger than 12 years than for children older than 12 years.Conclusions: These findings provide preliminary novel evidence that daytime sleepiness may drive the expression of emotional/behavioral disturbances, and should be explored as a potential modifiable risk factor for these disturbances in PWS, particularly pre-adolescent children. What is Known:• Individuals with Prader-Willi syndrome (PWS) commonly experience excessive daytime sleepiness and exhibit emotional/behavioral disturbances.• In the typically developing population, sleepiness is associated with emotional/behavioral disturbances, independently of sleep-disordered breathing.. What is New:• This study found evidence for a direct link between daytime sleepiness and emotional/behavioral disturbances, independent of sleep-related breathing difficulties, sleep adequacy, and body mass index.• Excessive daytime sleepiness may be a modifiable risk factor for emotional/behavioral disturbances in PWS.

Geographic variation of paediatric tonsillectomy, with or without adenoidectomy, (A/T) has been described since the 1930s until today but no studies have investigated the factors associated with this variation. This study described the geographical distribution of paediatric A/T across the state of Victoria, Australia, and investigated area-level factors associated with this variation. We used linked administrative datasets capturing all paediatric A/T performed between 2010 and 2015 in Victoria. Surgery data were collapsed by patient residence to the level of Local Government Area. Regression models were used to investigate the association between likelihood of surgery and area-level factors. We found a 10.2-fold difference in A/T rates across the state, with areas of higher rates more in regional than metropolitan areas. Area-level factors associated with geographic variation of A/T were percentage of children aged 5–9 years (IRR 1.07, 95%CI 1.01–1.14, P = 0.03) and low English language proficiency (IRR 0.95, 95% CI 0.90–0.99, P = 0.03). In a sub-population analysis of surgeries in the public sector, these factors were low maternal educational attainment (IRR 1.09, 95% CI 1.02–1.16, P P = 0.048). Identifying areas of focus for improvement and factors associated with geographic variation will assist in improving equitable provision of paediatric A/T and decrease variability within regions.

OBJECTIVE To describe the contemporary epidemiology of paediatric adenotonsillectomy in an Australian setting, examine the incidence rate over 2010-2015 and investigate factors associated with inter-hospital transfer. DESIGN Retrospective population-based study. SETTING Multicentre study in the state of Victoria, Australia. PARTICIPANTS From the Victorian Admitted Episodes Dataset, which included all patients aged 0-19 years who underwent adenoidectomy and/or tonsillectomy in Victoria, Australia between 2010 and 2015. MAIN OUTCOME MEASURES Annual incidence rate, hospital volume, inter-hospital transfer. RESULTS Between 2010 and 2015, 59 008 patients underwent 61 281 procedures, with highest number performed in males (52.7%), children aged under 10 years (73.5%) and in the higher socioeconomic groups (24.6% in quintile 4 and 23.2% in quintile 5). Seventy-five cases (0.12%) resulted in inter-hospital transfer, which was significantly associated with young age (under 5 years). More than a third of hospitals (35.7%) performed an average rate of

Sleep-disordered breathing (SDB) in children has been associated with craniofacial characteristics. Facial photography provides a radiation-free means of estimating facial morphology through facial landmark analysis. Our objective was to determine whether facial analysis provides information about SDB severity. Specifically, we aimed to determine whether facial photographic measurements differ with SDB status, or were associated with SDB severity. Single-center cohort of children undergoing overnight polysomnography for assessment of SDB; non-snoring controls were recruited from the community to undergo polysomnography. Standardized front and lateral facial photographs were analyzed according to previously published protocols. Multivariate analysis of variance was used to determine if facial measurements differed between SDB groups and controls. Linear regression was performed to determine if facial measurements were associated with SDB severity. Seventy-eight children (9 controls, 17 primary snoring, 23 mild SDB, 27 moderate-severe SDB) were included. Facial angles and upper-to-lower face height ratio showed variation between SDB groups (p = 0.038). Facial measurements related to SDB severity, specifically an increased cervicomental angle (p = 0.001), and increased lower-to-upper face height (p = 0.006). Evaluation of craniofacial features using clinical photography is feasible. Preliminary investigation shows some relationship with SBD severity. Further work is needed to determine if craniofacial photography is useful for stratifying SDB risk in children.

Prader‐Willi syndrome (PWS) is a rare genetic condition with multi‐system involvement. The literature was reviewed to describe neurodevelopment and the behavioural phenotype, endocrine and metabolic disorders and respiratory and sleep functioning. Implications for child and family quality of life were explored. Challenging behaviours contribute to poorer well‐being and quality of life for both the child and caregiver. Recent evidence indicates healthy outcomes of weight and height can be achieved with growth hormone therapy and dietary restriction and should be the current target for all individuals with PWS. Gaps in the literature included therapies to manage challenging behaviours, as well as understanding the effects of growth hormone on respiratory and sleep function. New knowledge regarding the transition of children and families from schooling and paediatric health services to employment, accommodation and adult health services is also needed. Developing a national population‐based registry could address these knowledge gaps and inform advocacy for support services that improve the well‐being of individuals with PWS and their families.

BACKGROUND AND OBJECTIVE Frequent central apnoeas are sometimes observed in healthy children; however; the pathophysiology of an elevated central apnoea index (CAI) is poorly understood. A raised CAI may indicate underlying ventilatory control instability (i.e. elevated loop gain, LG) or a depressed ventilatory drive. This pilot study aimed to compare LG in otherwise healthy children with an elevated CAI to healthy controls. METHODS Polysomnographic recordings from children (age > 6 months) without obstructive sleep apnoea and with a CAI > 5 events/h (n = 13) were compared with age and gender-matched controls with a CAI < 5 events/h (n = 13). Spontaneous sighs were identified during non-rapid eye movement (NREM) sleep, and breath-breath measurements of ventilation were derived from the nasal pressure signal. A standard model of ventilatory control (gain, time constant and delay) was used to calculate LG by transforming ventilatory fluctuations seen in response to a sigh into a ventilatory-drive signal that best matches observed ventilation. RESULTS The high CAI group had an elevated LG (median = 0.36 (interquartile range, IQR = 0.35-0.53) vs 0.28 (0.23-0.36); P ≤ 0.01). There was no difference in either the time constant (P = 0.63) or delay (P = 0.29) between groups. Elevated LG observed in the high CAI group remained after accounting for degree of hypoxia (average oxygen saturation (SpO2 ) during each analysable window) experienced (0.40 (0.30-0.53) vs 0.25 (0.23-0.37); P = 0.04). CONCLUSION An elevated CAI in otherwise healthy children is associated with a raised LG compared to matched controls with a low CAI, irrespective of level of hypoxia. This relative ventilatory instability helps explain the high CAI and may ultimately be able to help guide diagnosis and management in patients with high CAI.

Down syndrome (DS), the most common human chromosomal malformation, has an estimated annual incidence of one in 1000 live births worldwide. Sleep problems are common in children with DS, reported by parents in up to 65% of school-aged children, significantly higher rates than in typically developing (TD) children. Problems include difficulty in sleep initiation and maintenance together with obstructive sleep apnoea (OSA) which affects up to over 90%, of DS children compared with 1-5% in the general paediatric population. Any sleep problem has the potential to exert significant negative effects on daytime behaviour, learning and quality of life in TD children and there is now a growing body of evidence that children with DS are similarly affected. In addition to adverse effects on daytime functioning, OSA has adverse effects on the cardiovascular system and this is a particularly significant issue given the high rates of hypertension and premature cardiac disease in people with DS. This review discusses the effects of sleep problems and OSA on daytime functioning and cardiovascular function in children with DS and evidence of the effectiveness of treatment in improving outcomes and quality of life for these children.

Allergic rhinitis (AR) is a common risk factor for sleep disordered breathing (SDB) in children. Allergy to pollen is a trigger for allergic rhinitis, causing nasal inflammation, upper airway congestion and obstruction. We aimed to determine if the pollen count on the day of diagnostic polysomnography for SDB affected the result. Children (3–18 years; n = 90) who participated in research studies between 1 October and 31 December, when daily regional pollen counts were available, in the years 2005–2016 were eligible for inclusion. All children underwent overnight polysomnography for assessment of SDB severity. Pollen was categorised as grass or other pollen. Multiple stepwise linear regression was performed to determine whether the pollen count for that day, a diagnosis of asthma, age, and BMI-z-score were determinants of respiratory parameters measured on polysomnography, including the obstructive apnoea hypopnoea index (OAHI), SpO2 nadir, average SpO2 drop, SpO2 4% (ODI4), and average transcutaneous CO2 (TCM). Sixteen/90 children had AR. In children with AR, an increase in grass pollen of 1 grain/m3 predicted an increase in OAHI of 0.2 events/h, ODI4 of 0.18 times/h, SpO2

Children with Down syndrome (DS) are at increased risk of sleep-disordered breathing (SDB), which is associated with intermittent hypoxia and sleep disruption affecting daytime functioning. We aimed to compare the impact of SDB on sleep quality in children with DS compared to typically developing (TD) children with and without SDB.Children with DS and SDB (n = 44) were age- and sex-matched with TD children without SDB (TD-) and also for SDB severity with TD children with SDB (TD+). Children underwent overnight polysomnography with sleep macro- and micro-architecture assessed using electroencephalogram (EEG) spectral analysis, including slow-wave activity (SWA, an indicator of sleep propensity).Children with DS had greater hypoxic exposure, more respiratory events during REM sleep, higher total, delta, sigma, and beta EEG power in REM than TD+ children, despite the same overall frequency of obstructive events. Compared to TD- children, they also had more wake after sleep-onset and lower sigma power in N2 and N3. The DS group had reduced SWA, indicating reduced sleep drive, compared to both TD groups.Our findings suggest that SDB has a greater impact on sleep quality in children with DS compared to TD children.SDB in children with DS exacerbates disruption of sleep quality, compared to TD children. The prevalence of SDB is very high in children with DS; however, studies on the effects of SDB on sleep quality are limited in this population. Our findings suggest that SDB has a greater impact on sleep quality in children with DS compared to TD children, and should be screened for and treated as soon as possible.

Background Children with Down syndrome (DS) are at increased risk for sleep disordered breathing (SDB), which can have adverse effects on the cardiovascular system. In adults with SDB, nocturnal dipping of heart rate (HR) and blood pressure (BP) is reduced, and this is associated with an increased risk of future cardiovascular events. We aimed to compare nocturnal dipping of HR and pulse transit time (PTT) (a surrogate inverse measure of BP change) in children with DS and SDB to those of typically developing (TD) children with and without SDB. Methods 19 children with DS (3–18 years) were age and sex matched with 19 TD children without SDB (TD-) and with 19 TD children with matched severity of SDB (TD+). Nocturnal dipping was assessed as the percentage change in HR and PTT from wake before sleep onset to total sleep, N2, N3 and REM sleep across the night and to the first cycle of sleep. Results Children with DS exhibited reduced nocturnal dipping of HR during total sleep, N2, N3 and REM sleep and increased PTT (reduced BP dipping) in N2 sleep. Fewer children with DS exhibited a greater than 10% fall in HR between wake and N2 or REM sleep compared to TD+ children. Conclusions Our findings demonstrate significantly reduced nocturnal dipping of HR in children with DS compared to TD children matched for SDB severity, suggesting SDB has a greater cardiovascular effect in these children. Further studies are required to fully understand the mechanisms involved and to assess if treatment of SDB improves nocturnal dipping.

Objectives Children with Down syndrome (DS) are recommended to undergo polysomnography (PSG) by the age of four years due to the high prevalence of obstructive sleep apnea (OSA) in this group, but compliance is incomplete. To further understand referral patterns for PSG in this condition, we aimed to compare demographics, PSG results, OSA severity, behavior, daytime functioning and quality of life (QOL) between children with DS referred for sleep testing and those recruited from the community. Study design Children 3–19 years with DS was included: 20 referred clinically for assessment of OSA and 24 volunteers from the community. Demographic and anthropometric data, PSG parameters, sleep-related symptoms and QOL, behavior and daytime functioning were compared between groups. Results OSA severity did not differ between groups: 50% of the clinical and 42% of the community group had moderate/severe OSA. The clinical group had a higher weight z-score, BMI z-score, waist and hip circumference and neck-to-waist ratio. Questionnaire scores for daytime functioning, behavior and QOL were not different between groups. Conclusions Despite not being referred for clinical sleep assessment, 42% of children with DS recruited from the community had moderate/severe OSA. There was no difference in the QOL, behavior, daytime functioning and sleep symptoms questionnaires although the clinical group had a higher BMI-Z score and overt signs of obesity. These findings underscore the importance of PSG screening of all children with DS.

Aims To review the contributions of Australian and New Zealand research on adenotonsillectomy for the treatment of symptoms of obstructed breathing during sleep (sleep disordered breathing, SDB) in children. Methods A search of the scientific literature was conducted using the MEDLINE (Ovid), PubMed and Scopus databases in August 2020. The following search string was used: (tonsillectomy OR adenoidectomy OR adenotonsillectomy) AND (paediatric OR child) AND (Australia OR New Zealand). A focused internet search was additionally conducted on Google to identify grey literature. Results Researchers from Australia and New Zealand have made important contributions to the understanding and improvement of adenotonsillectomy (AT), including its epidemiology, cost, surgical techniques and peri-operative safety. Rates of AT have fluctuated over the years, becoming the most common paediatric surgery today, with SDB becoming the most common indication. Research in Australia and New Zealand has also focussed on the impact of AT on quality of life, and behaviour, neurocognition and cardiovascular sequelae. Conclusions Australian and New Zealand researchers have played a significant role in understanding the epidemiology and improving the safety of AT. There are promising directions in research still to come, including better understanding of the reasons for geographical variation in surgery rates, developing more efficient pre-operative risk assessment tools and alternative treatment options for mild OSA.

STUDY OBJECTIVES: An increasing number of children with obstructive sleep apnea (OSA) require treatment with continuous positive airway pressure (CPAP). This study aimed to determine whether automatic respiratory indices from a CPAP device accurately predict manually determined respiratory indices derived from overnight polysomnography (PSG) in children. METHODS: Consecutive children undergoing manual CPAP titration PSG using a ResMed VPAP ST-A (S9) were included. The apnea-hypopnea index (AHI), apnea index (AI), and hypopnea index (HI) from automatic analysis of the CPAP device for that night (AHI(CPAP), AI(CPAP), and HI(CPAP)) were compared with manually derived respiratory indices (RDI(PSG), OAHI(PSG), AI(PSG), and HI(PSG)) using the Wilcoxon matched-pairs signed-ranks test. RESULTS: Forty-six children (32 boys; median age, 13.5 years; range, 4.6–20.0 years) were included. There was no difference between RDI(PSG) and AHI(CPAP) (P = .6) nor between HI(PSG) and HI(CPAP) (P = .2). AI(PSG) was significantly lower than AI(CPAP) (mean difference −1.3 events/hr, P < .001). AI(PSG) and AI(CPAP) were strongly correlated (r(2) = .72, P < .01), but the CPAP machine overestimated the number of apneas at higher AIs. OAHI(PSG) was significantly lower than AHI(CPAP) (P = .003) but strongly correlated (r(2) = .87, P < .01). The CPAP device significantly underestimated the number of hypopneas at higher indices. Using the manually scored OAHI(PSG) of ≥5 events/hr to define significant residual OSA, the AHI(CPAP) had a high specificity (0.95) but low sensitivity (0.20). CONCLUSIONS: The ResMed S9 respiratory indices are not accurate enough to guide treatment decisions in children; in particular, they do not rule out the presence of residual OSA in children that remain symptomatic on CPAP. A low AHI(CPAP) is reassuring in the context of a stable patient but may miss ongoing hypopneas. CITATION: Mihai R, Ellis K, Davey MJ, Nixon GM. Interpreting CPAP device respiratory indices in children. J Clin Sleep Med. 2020;16(10):1655–1661.

Sleep disordered breathing (SDB) in typically developing (TD) children is associated with adverse cardiovascular effects. As children with Down syndrome (DS) are at increased risk for SDB, we aimed to compare the cardiovascular effects of SDB in children with DS to those of TD children with and without SDB.Forty-four children with DS (3-19 years) were age and sex matched with 44 TD children without SDB (TD-) and with 44 TD children with matched severity of SDB (TD+). Power spectral density was calculated from ECG recordings, for low frequency (LF), high frequency (HF), total power and the LF/HF ratio.Children with DS had lower HF power, and higher LF/HF during sleep and when awake. There were no differences between groups for LF power. SpOOur findings demonstrate significantly reduced parasympathetic activity (reduced HF power) and increased LF/HF (a measure of sympathovagal balance) in children with DS, together with greater exposure to hypoxia, suggesting SDB has a greater effect in these children that may contribute to an increased risk of adverse cardiovascular outcomes.Sleep disordered breathing in children with Down syndrome exacerbates impaired autonomic control and increases exposure to hypoxia, compared to typically developing children. In typically developing children sleep disordered breathing has adverse effects on autonomic cardiovascular control. The prevalence of sleep disordered breathing is very high in children with Down syndrome; however, studies on the effects on cardiovascular control are limited in this population. This study supports screening and early treatment of sleep disordered breathing in children with Down syndrome.

RationaleSevere acute paediatric asthma may require treatment escalation beyond systemic corticosteroids, inhaled bronchodilators and low-flow oxygen. Current large asthma datasets report parenteral therapy only.ObjectivesTo identify the use and type of escalation of treatment in children presenting to hospital with acute severe asthma.MethodsRetrospective cohort study of children with an emergency department diagnosis of asthma or wheeze at 18 Australian and New Zealand hospitals. The main outcomes were use and type of escalation treatment (defined as any of intensive care unit admission, nebulised magnesium, respiratory support or parenteral bronchodilator treatment) and hospital length of stay (LOS).Measurements and main resultsOf 14 029 children (median age 3 (IQR 1–3) years; 62.9% male), 1020 (7.3%, 95% CI 6.9% to 7.7%) had treatment escalation. Children with treatment escalation had a longer LOS (44.2 hours, IQR 27.3–63.2 hours) than children without escalation 6.7 hours, IQR 3.5–16.3 hours; pConclusionsOverall, 7.3% children with acute severe asthma received some form of escalated treatment, with 4.2% receiving parenteral bronchodilators and 4.3% respiratory support. There is wide variation treatment escalation.

Key points Sleep disordered breathing (SDB) affects 4-11% of children and is associated with adverse neurocognitive, behavioural and cardiovascular outcomes, including reduced autonomic control. The relationship between heart rate variability (HRV; a measure of autonomic control) and age found in non-snoring control children was absent during sleep in children with SDB. Age significantly predicted increasing cerebral oxygenation during wake in non-snoring control children, whereas during sleep, HRV significantly predicted decreasing cerebral oxygenation. Cerebral oxygenation was not associated with either age or HRV in children with SDB during both wake and sleep. SDB significantly disrupts the normal maturation of autonomic control and the positive association between autonomic control and cerebral oxygenation found in non-snoring children, and we speculate that the dampened autonomic control exhibited by children with SDB may have an attenuating effect on cerebral autoregulation via the moderating influence of HRV on cerebral blood flow. Abstract The repetitive episodes of hypoxia that are features of sleep disordered breathing (SDB) in children are associated with alterations in autonomic control of heart rate in an age-dependent manner. We aimed to relate heart rate variability (HRV) parameters to age and measures of cerebral oxygenation in children (3-12 years old) with SDB and non-snoring controls. Children (SDB, n = 117; controls, n = 42; 3-12 years) underwent overnight polysomnography. Total (TP), low- (LF) and high-frequency (HF) power, tissue oxygenation index (TOI) and fractional tissue oxygen extraction (FTOE) were analysed during wake and sleep. Pearson's correlations determined the association between age and HRV parameters, and multiple linear regressions between HRV, age and cerebral oxygenation parameters. During wake, age had a positive association with LF power, reflecting increased parasympathetic and sympathetic activity with increasing age for both control and SDB groups. This association was also evident during sleep in controls, but was absent in children with SDB. In controls, during wake TOI had a positive, and FTOE a negative association with age. During sleep, TP, LF and HF power were significant, negative determinants of TOI and positive determinants of FTOE. These associations were not seen in children with SDB during wake or sleep. SDB disrupts the normal maturation of the autonomic control of heart rate and the association between HRV and cerebral oxygenation exhibited by non-snoring control children of primary school age. These results highlight the impact SDB has on cardiovascular control and the potential impact on adverse cardiovascular outcomes.

Background We aimed to investigate the relationship between sleep quality, mood and health-related quality of life (HRQOL) in children with CF and controls. Methods Children (7–12years) and adolescents (13–18years) with CF and controls completed sleep evaluation: overnight oximetry and 14days of actigraphy. Age-appropriate questionnaires assessed mood (Children's Depression Inventory; CDI or Beck's Depression Inventory), HRQOL (CF Questionnaire-Revised; CFQ-R or PedsQL), and sleepiness (Pediatric Daytime Sleepiness Scale). Results 87 CF and 55 controls recruited. Children with CF had poorer sleep quality, more sleepiness and lower mood than controls, with a negative correlation between mood score and sleep efficiency. Sleepiness score was predictive of mood score and multiple CFQ-R domains. Adolescents with CF also demonstrated poorer sleep and more sleepiness than controls, but no difference in mood. Reduced sleep quality predicted lower CFQ-R scores. No correlation between sleep, mood or HRQOL in controls. Conclusions In children and adolescents with CF, impaired sleep quality is associated with lower mood and HRQOL in an age-specific manner. Future research will aid understanding of effective strategies for prevention and treatment of mood disorders and sleep disturbance in children with CF.

Childhood sleep-disordered breathing ranges in severity from primary snoring to obstructive sleep apnea and is associated with behavioral and neurocognitive deficits. It remains unknown why children with primary snoring, who do not experience peripheral oxygen desaturation or sleep fragmentation, experience similar daytime deficits as those with obstructive sleep apnea or why effects are age-dependent.To examine cerebral tissue oxygenation and oxygen extraction as an explanation for daytime deficits in children with primary snoring.Children referred for suspected sleep-disordered breathing and nonsnoring control subjects underwent overnight polysomnography with near-infrared spectroscopy. Children were categorized into 3- to 6-year (n = 87) and 7- to 12-year (n = 72) old groups, and according to the obstructive apnea-hypopnea index into primary snoring (≤1 event/h), mild (1-5 events/h), and moderate/severe obstructive sleep apnea (5 events/h). Cognitive and behavioral performance were assessed.In the 3- to 6-year group, there were no differences in cerebral oxygenation or oxygen extraction between severity groups. In the 7- to 12-year group, cerebral oxygenation was significantly lower, although these differences were small, in control subjects versus primary snoring during quiet wakefulness before sleep onset, N1, and REM. Oxygen extraction was significantly higher in control subjects versus primary snoring during N1 sleep, with no differences between primary snoring and obstructive sleep apnea groups. Cerebral oxygenation was not associated with cognitive performance in either age group or behavior in the 3- to 6-year group; however, it was associated with behavior in the school-aged children.Children with sleep-disordered breathing are able to maintain cerebral oxygenation, and the small changes observed are not related to cognitive deficits. However, in older children these differences were related to behavioral measures.

Background Sleep disturbance is common in children with cystic fibrosis (CF) however there are limited studies investigating the causes for poor sleep quality. In a cross sectional observational study we aimed to evaluate the clinical correlates of sleep disturbance in this population. Methods Children with CF (7-18years) free from pulmonary exacerbation completed medical review, overnight oximetry, the OSA-18 and 14days of actigraphy recordings with a sleep diary. Results In addition to FEV1 Conclusions Reduced sleep quality in children with CF is related to lung health and co-morbidities. However, family characteristics and poor sleep hygiene in the child were also associated with sleep disturbance. Optimal management of CF would seem to be the primary intervention to alleviate children's sleep disturbance, however our data raises additional targets for attempts to improve sleep.

To measure sleep patterns and quality, objectively and subjectively, in clinically stable children with cystic fibrosis (CF) and healthy control children, and to examine the relationship between sleep quality and disease severity.Clinically stable children with CF and healthy control children (7-18 years of age) were recruited. Sleep patterns and quality were measured at home with actigraphy (14 days). Overnight peripheral capillary oxygen saturation was measured via the use of pulse oximetry. Daytime sleepiness was evaluated by the Pediatric Daytime Sleepiness Scale (PDSS) and subjective sleep quality by the Sleep Disturbance Scale for Children and Obstructive Sleep Apnea-18.A total of 87 children with CF and 55 control children were recruited with no differences in age or sex. Children with CF had significantly lower total sleep time and sleep efficiency than control children due to frequent awakenings and more wake after sleep onset. In children with CF, forced expiratory volume in 1 second and overnight peripheral capillary oxygen saturation nadir correlated positively with total sleep time and sleep efficiency and negatively with frequency of awakenings and wake after sleep onset. Patients with CF had significantly greater Sleep Disturbance Scale for Children (45 vs 35; P .001), Obstructive Sleep Apnea-18 (35 vs 24; P .001), and PDSS scores (14 vs 11; P .001). There was a negative correlation between PDSS and forced expiratory volume in 1 second (r = -0.23; P .05).Even in periods of clinical stability, children with CF get less sleep than their peers due to more time in wakefulness during the night rather than less time spent in bed. Objective measures of sleep disturbance and subjective daytime sleepiness were related to disease severity. In contrast, parents of children with CF report high levels of sleep disturbance unrelated to disease severity.

BACKGROUND AND OBJECTIVE The contribution of non-anatomical factors, such as ventilatory control instability (i.e. LG), to the pathogenesis of obstructive SDB in children is unclear. Therefore, we aimed to identify the relationship between LG and severity of SDB, demographic, anthropometric and anatomical characteristics in a clinically representative cohort of children. METHODS Children (aged 3-18 years) with various severities of SDB (n = 110) and non-snoring controls (n = 36) were studied. Children were grouped according to their OAHI. Anthropometric and upper airway anatomical characteristics were measured. Spontaneous sighs were identified on polysomnography and LG, a measure of the sensitivity of the negative feedback loop that controls ventilation, was estimated by fitting a mathematical model of ventilatory control to the post-sigh ventilatory pattern. RESULTS There was no difference in LG between controls and any of the SDB severity groups. However, LG was significantly lower in children with larger tonsils (tonsil grade 4) compared with children with smaller tonsils (tonsil grade 1) (median LG (range): 0.25 (0.20-0.42) vs 0.32 (0.25-0.44); P = 0.009) and in children with a modified Mallampati score of class III/IV compared with class I (0.28 (0.24-0.33) vs 0.37 (0.27-0.44); P = 0.009). CONCLUSION A direct relationship was not found between the severity of paediatric SDB and LG. However, an altered ventilatory control sensitivity may contribute to SDB in a subgroup of children depending on their degree of anatomical compromise of the airway.

Study ObjectivesSleep disordered breathing (SDB) in children has significant effects on daytime functioning and cardiovascular control; attributed to sleep fragmentation and repetitive hypoxia. Associations between electroencephalograph (EEG) spectral power, autonomic cardiovascular control and cerebral oxygenation have been identified in adults with SDB. To date, there have been no studies in children. We aimed to assess associations between EEG spectral power and heart rate variability as a measure of autonomic control, with cerebral oxygenation in children with SDB.MethodsOne hundred sixteen children (3–12 years) with SDB and 42 controls underwent overnight polysomnography including measurement of cerebral oxygenation. Power spectral analysis of the EEG derived from C4-M1 and F4-M1, quantified delta, theta, alpha, and beta waveforms during sleep. Multiple regression tested whether age, SDB severity, heart rate (HR), HR variability (HRV), and cerebral oxygenation were determinants of EEG spectral power.ResultsThere were no differences in EEG spectral power derived from either central or frontal regions for any frequency between children with different severities of SDB so these were combined. Age, HR, and HRV low frequency power were significant determinants of EEG spectral power depending on brain region and sleep stage.ConclusionThe significant findings of this study were that age and autonomic control, rather than cerebral oxygenation and SDB severity, were predictive of EEG spectral power in children. Further research is needed to elucidate how the physiology that underlies the relationship between autonomic control and EEG impacts on the cardiovascular sequelae in children with SDB.

Both preterm birth and sleep disordered breathing (SDB) affect sleep in children. We compared the effects of SDB on sleep macro-architecture and micro-architecture in children born preterm (N = 50) and children born at term (N = 50). We hypothesized that sleep would be more disrupted in children born preterm.Polysomnographic studies matched for age (3-12 years) and SDB severity were analyzed. Sleep macro-architecture was assessed using standard criteria and micro-architecture was evaluated using spectral analysis of the electroencephalogram and slow wave activity (SWA) calculated for each sleep stage across the night.Ex-preterm children (gestational age 29.3 ± 3.6 weeks, mean ± standard error of the mean) were not different from controls for demographic or respiratory parameters or sleep macro-architecture. Theta power in N2 tended to be higher for F4 (p 0.05) and C4 (p 0.07). In the second non-rapid eye movement period, SWA was significantly higher in the preterm group compared to the term group for both F4 and C4 (p 0.05 for both).Sleep micro-architecture in children born preterm showed increased theta power and SWA. These differences provide evidence of increased sleep debt and reduced dissipation of sleep debt across the night. Further studies are required to identify if these findings are related to impaired neurocognition and behavior.

Study objectives Both central and obstructive respiratory events are features of sleep disordered breathing. The repetitive hypoxia associated with obstructive events is believed to underpin the adverse neurocognitive and cardiovascular sequelae of this disorder, however whether central events contribute to this has not been investigated. To compare changes in cerebral and peripheral oxygenation, blood pressure and heart rate, associated with central and obstructive events in children aged 3-6 and 7-12 years. Methods Sixty children referred for suspected sleep disordered breathing underwent overnight polysomnography. Beat-by-beat analysis determined changes from baseline in cerebral oxygenation, peripheral oxygen saturation, fractional tissue oxygen extraction, pulse transit time (a surrogate measure of blood pressure change), and heart rate, associated with central and obstructive respiratory events, during NREM and REM sleep. Results Eight hundred ninty-two events were analyzed: 493 central and 399 obstructive. Central events had a greater % change from baseline in cerebral oxygenation and heart rate nadir compared with obstructive events and these were greater in NREM compared with REM sleep. The 3- to 6-year-old children experienced a greater % change in TOI compared with the 7-12 year olds, while % change in heart rate was greater in 7-12 year olds. Conclusion Central respiratory events had similar falls in cerebral oxygenation and heart rate to obstructive events and should be considered when examining the sequelae of sleep disordered breathing, particularly as central events are common in children with sleep disordered breathing.

Background In 2012 clinical management of children having adenotonsillectomy (AT) for suspected obstructive sleep apnea (OSA) at our tertiary centre changed based on previous research: children with severe obstructive sleep apnea (OSA) at increased risk of post-operative respiratory adverse events (AE) identified using home overnight oximetry or polysomnography (PSG) were managed post-operatively in a high nurse/patient ratio unit in the ward (high acuity unit, HAU) rather than in the intensive care unit (ICU) as previously. Objectives To examine the post-operative respiratory AE post AT in HAU. Methods A retrospective audit was performed of children having AT on the HAU list from Oct 2012–Sept 2014, identifying clinical information, pre-operative testing for OSA and post-operative course. Results 343 children underwent elective adenotonsillectomy at our tertiary centre in the study period, of whom 79 had surgery on the HAU list (16F; median age 4.2 year (range 1.2–14.7); median weight-for-age centile 77.9% (IQR 44–98.7%)). 75 had moderate/severe OSA by oximetry ( n = 44) or PSG ( n = 31) criteria. 77 of 79 children had oxygen therapy in the recovery room (median 20 min, IQR 15–40 min). 18 (23%) had at least one AE outside the recovery room, which were observed ( n = 2) or treated with oxygen therapy ( n = 14) or repositioning ( n = 2). Obesity increased the risk of an AE (10/25 obese vs 8/54 non obese, p = 0.01), as did the presence of a major comorbidity (5/9 with comorbidity vs 13/70 without, p = 0.03). There were no admissions from the HAU to ICU. 63 patients (83%) stayed only one night in hospital (median 1 d, range 1–5 d). Conclusions In a cohort of children with known moderate-severe OSA, post-operative AE after AT were all managed in the HAU. Post-operative care in HAU provides safe and effective care for high-risk children post-AT, minimizing admissions to ICU.

To develop and test a screening tool based on the OSA-18 questionnaire for triage of referrals for sleep-disordered breathing (SDB) in children.Consecutive children aged2y without major comorbidities referred for polysomnography (PSG) or overnight oximetry for suspected obstructive sleep apnea (OSA) between 11 January and 31 May 2017 were included. OSA was defined by an obstructive apnea/hypopnea index (OAHI)1event/h on PSG or an abnormal overnight oximetry (McGill Oximetry Score 2-4). An 11-item questionnaire derived from a previous validation study of the OSA-18 underwent exploratory factor analysis (EFA) with varimax rotation. ANOVA identified questions associated with the presence of OSA. This informed a 5-question, 4-category instrument, scored 0-15 (the OSA-5), that was tested prospectively on 112 children having PSG.420 children (2.0-17.9y, 43% female) met the inclusion criteria, including 366 complete questionnaires. EFA resulted in a 3-factor structure. ANOVA identified 5 questions from one factor that were independently associated with a diagnosis of OSA: snoring, breath holding, choking, mouth breathing and parental concern. Mean OSA-5 scores with and without OSA were 7.7 vs 4.5 (p 0.001). Thirty-four percent (60/178) had a total score5/15, with a sensitivity at this threshold for OSA of 82% and negative predictive value (NPV) of 70%. Similar results were obtained when tested prospectively, including a sensitivity of 82% and NPV of 81% for the presence of moderate/severe OSA (OAHI5/h).The OSA-5 is a simple questionnaire that performs well as a triage screening tool to identify those children at risk of OSA among large numbers of referrals for SDB.

Sleep disordered breathing (SDB) in preschool-aged children is common, but long-term outcomes have not been investigated. We aimed to compare sleep and respiratory parameters in preschool children to examine the effects of treatment or non-treatment after 3 years.Children (3-5 years) diagnosed with SDB (n = 45) and non-snoring controls (n = 30) returned for repeat overnight polysomnography (39% of original cohort), 3 years following baseline polysomnography. Children with SDB were grouped according to whether they had received treatment or not. SDB resolution was defined as an obstructive apnea hypopnea index (OAHI) ≤ 1 event/h, no snoring detected on polysomnography and habitual snoring not indicated by parents on questionnaire.Fifty-one percent (n = 23) of the children with SDB were treated. Overall, SDB resolved in 49% (n = 22), either spontaneously (n = 8) or with treatment (n = 14). SDB remained unresolved in 39% (n = 9) of those treated and 64% (n = 14) of the children who were untreated. Two of the non-snoring controls developed SDB at follow-up. The treated group had significantly lower OAHI (p0.01), respiratory disturbance index (p0.001), total arousal and respiratory arousal indices (p0.01 for both) at follow-up compared with baseline. There were no differences between studies for the untreated group.Although treatment resulted in an improvement in indices related to SDB severity, 39% had SDB 3 years following diagnosis. These findings highlight that parents should be made aware of the possibility that SDB may persist or recur several years after treatment. This is relevant regardless of the severity of SDB at baseline and the treatment given.

The prevalence of obese children with sleep disordered breathing (SDB) is increasing. Obesity and SDB are independent cardiovascular risk factors, of which arterial stiffness is an early sign. Pulse wave velocity (PWV), is a marker of arterial stiffness and central systolic blood pressure (cSBP) is a better predictor of cardiovascular outcome than peripheral blood pressure. Therefore, we aimed to determine PWV and cSBP in overweight/obese or normal weight children with sleep disordered breathing (SDB), and non-snoring normal weight controls.Children (3-18 y) with SDB (overweight/obese [BMI z-scores ≥ 1.04], n = 48; normal weight n = 44) referred for clinical assessment of SDB and normal weight non-snoring controls recruited from the community (n = 38) underwent overnight polysomnography. PWV was calculated using photoplethysmography. cSBP was calculated using applanation tonometry in a subset of children older than 8 y (n = 55) who had usable waveforms.Overweight/obese SDB group had higher PWV (mean cm/s (95% CI); wake: 366 (355-380); sleep: 340 (324-357)), than the normal-weight SDB group (wake: 257 (247-267), p = 0.002; sleep: 255 (242-269), p = 0.005), and non-snoring controls (wake: 238 (226-249), p = 0.002; sleep: 235 (220-250), p 0.001). The normal-weight SDB group had higher PWV than controls (p = 0.03). Overweight/obese children with SDB had higher cSBP (105 (100-110) mmHg) compared with the normal weight children with SDB (96 (90-102)) and the non-snoring controls (97 (91-104); p 0.05 for both).This study suggests that overweight/obesity substantially worsens the cardiovascular sequelae of SDB, highlighting the imperative to treat obesity and SDB in children early in order to reduce future cardiovascular disease risk.

Obesity and anthropometric measurements predict more severe sleep-disordered breathing (SDB) in children, and are associated with cardiovascular risk factors in children without SDB. We aimed to investigate whether anthropometric measurements predicted autonomic control in children with SDB. We hypothesised that anthropometric measures would be significant predictors of decreased heart rate variability. Children (3–17 years) with SDB (n = 298) and non-snoring controls (n = 126) underwent polysomnography. BMI z-score, neck, waist and hip circumference were recorded. Heart rate variability, indicating autonomic control, was analysed during wake, non-rapid eye movement stages N1, N2 and N3, and rapid eye movement (REM) sleep. The determinants of heart rate variability (low-frequency power [LF], high-frequency power [HF] and LF/HF ratio) were analysed using multiple stepwise linear regression. Independent variables were age, neck, waist and hip circumference, neck-to-waist ratio, waist-to-hip ratio and waist-to-height ratio, obstructive apnoea hypopnoea index, arousal index and SpO2 nadir. Waist and hip circumference, and waist-to-height ratio were significant negative determinants of both HF and LF power during wake, reflecting dampened autonomic control (LF: waist/height ratio, B = −1917 (95% CI: −3640, −194), p = 0.03; HF: hip circumference, B = −27, (−48, −7), p = 0.01), N1&2 (LF/HF: hip circumference, B = 0.01 (0.004, 0.024), p = 0.005) and N3 (LF: waist/height ratio, B = −2495, (−4005, −986), p = 0.001; HF, hip circumference, B = −54, (−102, −6), p = 0.03; LF/HF, waist circumference, B = 0.01, (0.004, 0.015), p = 0.002). Age was the strongest determinant of heart rate variability during wake and sleep. This study suggests that while age is a determinant of autonomic control in children with SDB, the strongest modifiable factor determining dampened autonomic control is increased central adiposity, as reflected in the waist and hip circumference and the waist-to-height ratio.

This study aimed to examine slow wave activity (SWA), a marker of homeostatic regulation, as a potential mechanism linking sleep disordered breathing (SDB) with executive dysfunction in children. Executive function domains of working memory, spatial planning, information processing, and sustained attention were assessed using the Cambridge Neuropsychological Test Automated Battery (CANTAB) in children (N = 40; 5–12 years) referred for clinical diagnosis of SDB. Polysomnography records of non-snoring, age-matched controls (N = 34) were retrospectively examined for comparison of SWA. Power spectral analysis of the delta wave determined SWA. Group differences in sleep, respiratory, and SWA outcomes were examined. Mean CANTAB scores were compared to standardized norms and correlated against SWA. Children with SDB showed increased SWA compared to non-snoring controls and scored

Up to 50% of overweight/obese children have obstructive sleep apnea (OSA) compared to up to 6% of normal weight children. We compared cardiovascular variables between normal weight and overweight/obese children with and without OSA, and controls.Seventy-four referred children and 24 normal weight non-snoring controls (8-18 years) were recruited. Referred children were grouped according to their obstructive apnea hypopnea index (OAHI): OSA (1 event/h) or primary snoring (PS ≤ 1 event/h) and whether they were normal weight (BMI z-score1.04) or overweight/obese (BMI z-score ≥ 1.04). Wake blood pressure (BP), heart rate (HR), and pulse transit time (PTT, an inverse continuous surrogate measure of blood pressure) during sleep were recorded.Wake BP was higher in the overweight/obese OSA group than in the control, normal weight PS, and overweight/obese PS groups (p 0.05 for all). During sleep, BP, and HR were elevated in the overweight/obese OSA group compared to those in non-snoring controls (p 0.05). More children who were overweight/obese had reduced BP and HR dipping from wake to sleep than normal weight children. The BMI z-score predicted HR and PTT when asleep and both age and BMI z-score predicted BP when awake.This study showed that BMI has both combined and independent effects on BP and HR in children with OSA. We have previously shown that treatment of OSA reduces BP and suggest that treatment of OSA in the growing number of overweight/obese children may improve cardiovascular outcomes.

This study aimed to determine whether overweight and obesity increased the detrimental effects of pediatric sleep-disordered breathing (SDB) on cognition, behavior, mood, and quality of life.Children and adolescents (8-16 years) with clinically diagnosed SDB were categorized into two groups: healthy weight (Body Mass Index (BMI) z-score1.04, N = 11) and overweight/obese (BMI z-score ≥ 1.04, N = 10). Age-matched healthy weight, non-snoring controls (N = 25) were recruited from the community. All participants underwent overnight laboratory polysomnography (PSG). Cognitive, behavioral, and quality of life assessments were conducted in the home following the PSG. Analysis of Covariance (ANCOVA) was used to assess group differences in cognitive outcomes, controlling for socio-economic status. Kruskal-Wallis ANOVA was used to determine group differences in behavior and quality of life. Where group differences were found, hierarchical linear regressions determined the effect of weight on outcomes.Children with SDB had significantly poorer behavior and quality of life than controls, with overweight/obese children with SDB having the greatest dysfunction. No group differences were found in cognitive outcomes. The obstructive apnea hypopnea index (OAHI) was a significant predictor of withdrawn behavior (ROverweight and obesity comorbid with SDB increase the risk of externalizing behaviors such as aggression but do not affect other behavioral associates of SDB such as inattention and school functioning.

In 2007 the American Academy of Sleep Medicine (AASM) published polysomnography (PSG) scoring guidelines, which were updated in 2012. A key change in terms of scoring respiratory events in children was the threshold for reduction in airflow (50% vs 30%) for the definition of hypopnea. This study aimed to determine the impact of different scoring rules on the assessment of severity of obstructive sleep apnea (OSA) in children.Forty-two children (mean age 4.3 y, 16 F) underwent PSG. An obstructive apnea-hypopnea index (OAHI) was determined using three scoring rules: (1) ATS 1996 rules with minor modifications (modified ATS 1996); (2) AASM 2007 rules (AASM 2007); and (3) AASM 2007 rules with respiratory event related arousals included in the OAHI (AASM+RERA).The AASM 2007 OAHI (median 0.4 events/h, range 0, 14) was lower than the modified ATS 1996 OAHI (median 0.8 range 0, 26.1, p0.001), underestimating severity of disease in 24% of cases. The AASM+RERA OAHI (median 0.8, range 0, 19.1) was also lower than the modified ATS 1996 OAHI (p = 0.02), but the difference was not clinically significant except at very high OAHIs.The AASM 2007 rules lead to a lower OAHI and lesser OSA severity when compared to the previous standard. Inclusion of RERAs in the AASM 2007 OAHI leads to a comparable OAHI to the previous rules. Given that morbidity has been demonstrated even in mild OSA, these results support the inclusion of events with a reduction in airflow of less than 50% as included in the updated AASM rules in 2012.

Objective To compare symptoms of obstructive sleep apnea (OSA) and polysomnography (PSG) results in children with Down syndrome and typically developing children. Study design A total of 49 children with Down syndrome referred for PSG between 2008 and 2012 were matched with typically developing children of the same sex, age, and OSA severity who had undergone PSG in the same year. A parent completed a sleep symptom questionnaire for each child. Sleep quality and measures of gas exchange were compared between the matched groups. Results The 98 children (46 females, 52 males) had mean age of 6.2 years (range, 0.3-16.9 years). Fourteen children had primary snoring, and 34 had OSA (9 mild, 7 moderate, and 19 severe). Children with Down syndrome had more severe OSA compared with 278 typically developing children referred in 2012. Symptom scores were not different between the matched groups. Those with Down syndrome had a higher average pCO 2 during sleep ( P = .03) and worse McGill oximetry scores. Conclusion Compared with closely matched typically developing children with OSA of comparable severity, children with Down syndrome had a similar symptom profile and slightly worse gas exchange. Referred children with Down syndrome had more severe OSA than referred typically developing children, suggesting a relative reluctance by parents or doctors to investigate symptoms of OSA in children with Down syndrome. These findings highlight the need for formal screening tools for OSA in children with Down syndrome to improve detection of the condition in this high-risk group.