Neurocognitive dysfunction and grey matter density deficit in children with obstructive sleep apnoea

Aberrant Resting-State Effective Connectivity Between the Insula and Other Regions of the Whole Brain in Children With Obstructive Sleep Apnea

To investigate the effective connectivity between the bilateral insulae and other regions of the whole brain in children with obstructive sleep apnea (OSA), and to reveal the relationships between these abnormal connections and cognitive dysfunction in this condition. Resting-state functional magnetic resonance imaging (rs-fMRI) data and clinical variables were collected from 55 children with OSA [5.0 (5.0, 8.0) years, 32 males, 28 pre-school children] and 25 healthy controls [6.0 (5.0, 9.0) years, 11 males, 9 pre-school children], matched for age, gender, and education. Rs-fMRI data were analysed to investigative group-difference in the effective connectivity between the bilateral insulae and other regions of the brain of children with OSA with those of controls. Spearman correlation analysis was conducted between these abnormal connections and clinical variables among children with OSA. Compared with controls, children with OSA showed abnormal clinical variables (i.e., increased OAHI, AHI, OAI, HI, ODI, time of SpO2 < 90%, total AI, and respiratory-related AI, while decreased minimal SpO2, FIQ, VIQ, and PIQ). Additionally, significant alterations were observed in the effective connectivity between the bilateral insulae and other regions of brain, such as frontal, parietal, occipital, and cerebellum and so forth. Furthermore, the mean values of the effective connectivity in children with OSA were significantly correlated with several sleep-related and neurocognitive parameters. There exist abnormal causal interactions between the bilateral insulae and other regions throughout the brain in OSA children, accompanied by impaired cognitive function, suggesting that the former may be a potential neural mechanism underlying the latter.

Altered cerebral white matter network topology and cognition in children with obstructive sleep apnea

OBJECTIVES

The study aimed to explore the underlying mechanisms of OSA-related cognitive impairment by investigating the altered topology of brain white matter networks in children with OSA.

METHODS

Graph theory was used to examine white matter networks' network topological properties in 46 OSA and 31 non-OSA children. All participants underwent MRI, polysomnography, and cognitive testing. The effects of the obstructive apnea-hypopnea index (OAHI) on topological properties of white matter networks and network properties on cognition were studied using hierarchical linear regression. Mediation analyses were used to explore whether white matter network properties mediated the effects of OAHI on cognition.

RESULTS

Children with OSA had significantly higher assortativity than non-OSA children. Furthermore, OAHI was associated with the nodal properties of several brain regions, primarily in the frontal and temporal lobes. The relationship between OAHI and verbal comprehension index was mediated through clustering coefficients in the right temporal pole of the superior temporal gyrus.

CONCLUSIONS

OSA affects the development of white matter networks in children's brains. Besides, the mediating role of white matter network properties between the OAHI and the verbal comprehension index provided neuroimaging evidence of impaired cognitive function in children with OSA.

Association between habitual snoring and vigilant attention in elementary school children

OBJECTIVES

Vigilant attention (VA) is a fundamental neurocognitive function. However, the association between habitual snoring (HS) and VA in community-based children remains unclear. Therefore, this study aimed to elucidate the association.

METHODS

The study included 2014 children from grades 1-6 across six elementary schools. Snoring frequency was evaluated using a questionnaire administered to parents. VA was assessed using a brief 3-min psychomotor vigilance test (PVT-B). Generalized linear models and multivariate logistic regression analysis were utilized to examine the association between snoring frequency and PVT-B performance. Impaired PVT-B performance was defined as the worst quartile of PVT-B metrics.

RESULTS

The PVT-B performance significantly improved with advancing school grade level (p trend < 0.0001). A significant negative correlation was observed between snoring frequency and PVT-B performance. Particularly, in grade 1, HS was associated with a higher risk of impaired PVT-B performance, including response speed (mean reciprocal reaction time) (adjusted odds ratio [aOR] 2.56, 95% confidence interval [CI]: 1.20-5.50), more slowest 10% RT (aOR 3.28, 95% CI: 1.51-6.88), and more lapse500 (number of lapse of reaction time ≥ 500 ms) (aOR 3.18, 95% CI: 1.45-6.80) compared to children without snoring.

CONCLUSIONS

Our findings show that VA rapidly improves throughout elementary school. Additionally, younger children with HS are at risk of VA deficits, emphasizing the importance of early intervention for HS.

Cortical grey matter changes, behavior and cognition in children with sleep disordered breathing

This paper investigated cortical thickness and volumetric changes in children to better understand the impact of obstructive sleep disordered breathing (SDB) on the neurodevelopment of specific regions of the brain. We also aimed to investigate how these changes were related to the behavioral and cognitive deficits observed in the condition. Neuroimaging, behavioral, and sleep data were obtained from 30 children (15 non-snoring controls, 15 referred for assessment of SDB) aged 7 to 17 years. Gyral-based regions of interest were identified using the Desikan-Killiany atlas. Student's t-tests were used to compare regions of interest between the controls and SDB groups. We found that the cortical thickness was significantly greater in the right caudal anterior cingulate and right cuneus regions and there were volumetric increases in the left caudal middle frontal, bilateral rostral anterior cingulate, left, right, and bilateral caudate brain regions in children with SDB compared with controls. Neither cortical thickness nor volumetric changes were associated with behavioral or cognitive measures. The findings of this study indicate disruptions to neural developmental processes occurring in structural regions of the brain; however, these changes appear unrelated to behavioural or cognitive outcomes.

Effects of childhood obstructive sleep apnea with and without daytime sleepiness on behaviors and emotions

OBJECTIVE

To investigate the relationship between obstructive sleep apnea (OSA) with and without excessive daytime sleepiness (EDS) and behavioral and emotional outcomes in non-obese prepubertal children.

METHODS

This was a retrospective analysis of children aged 5-11 years who presented to our unit for assessment of their sleep-related complaints. All children underwent polysomnography (PSG). They also completed the Pediatric Daytime Sleepiness Scale (PDSS) and a sleep diary. OSA was diagnosed if the obstructive apnea-hypopnea index (OAHI) was ≥1 event/hour. EDS was defined as PDSS >15. Behavioral and emotional outcomes were assessed using the Child Behavioral Checklist (CBCL).

RESULTS

Data from 391 children (mean age of 8.6 ± 1.7 years; 67 % male) were analyzed. Seventy children did not have OSA or EDS, 137 had OSA, 50 had reported having EDS but without OSA, and 134 children had both OSA and EDS. There were significantly higher CBCL total problems score in the combined group (61 ± 9) compared to the non-OSA/EDS group (54 ± 10), and the OSA-only group (54 ± 10) (p < 0.001). The presence of EDS was significantly associated with higher CBCL T score and higher odds for clinically significant behavioral problems (T score ≥65) after adjusting for age, sex, BMI z-score and average sleep duration (p < 0.001).

CONCLUSION

Excessive daytime sleepiness is an important contributory factor associated with suboptimal behavioral and emotional outcomes in children with OSA.

Characteristics of ADHD Symptoms and EEG Theta/Beta Ratio in Children With Sleep Disordered Breathing

Objectives. This study aimed to explore parent-reported symptoms of attention deficit-hyperactivity disorder (ADHD) and sleep electroencephalogram (EEG) theta/beta ratio (TBR) characteristics in children with sleep disordered breathing (SDB). Methods. The parents of children (aged 6-11 years) with SDB (n = 103) and healthy controls (n = 28) completed the SNAP-IV questionnaire, and children underwent overnight polysomnography. Children with SDB were grouped according to obstructive apnea/hypopnea index: primary snoring, mild, and moderate-severe obstructive sleep apnea (OSA) groups. The TBR in non-rapid eye movement (NREM) periods in three sleep cycles was analyzed. Results. Children with SDB showed worse ADHD symptoms compared with the healthy control. There was no intergroup difference in TBR. The time-related decline in TBR observed in the control, primary snoring and mild OSA groups, which was not observed in the moderate-severe OSA group. Overnight transcutaneous oxygen saturation was negatively associated with the hyperactivity/impulsivity score of ADHD symptom. The global TBR during the NREM period in the first sleep cycle was positively correlated with inattention score. Conclusion. Children with SDB showed more ADHD inattention symptoms than the healthy control. Although we found no difference in TBR among groups, we found significant main effect for NREM period. There existed a relationship between hypoxia, TBR, and scores of ADHD symptoms. Hence, it was speculated that TBR can reflect the nocturnal electrophysiological manifestations in children with SDB, which may be related to daytime ADHD symptoms.

Abnormal interaction between cortical regions of obstructive sleep apnea hypopnea syndrome children

Obstructive sleep apnea hypopnea syndrome negatively affects the cognitive function of children. This study aims to find potential biomarkers for obstructive sleep apnea hypopnea syndrome in children by investigating the patterns of sleep electroencephalography networks. The participants included 16 mild obstructive sleep apnea hypopnea syndrome children, 12 severe obstructive sleep apnea hypopnea syndrome children, and 13 healthy controls. Effective brain networks were constructed using symbolic transfer entropy to assess cortical information interaction. The information flow pattern in the participants was evaluated using the parameters cross-within variation and the ratio of posterior-anterior information flow. Obstructive sleep apnea hypopnea syndrome children had a considerably higher symbolic transfer entropy in the full frequency band of N1, N2, and rapid eye movement (REM) stages (P < 0.05), and a significantly lower symbolic transfer entropy in full frequency band of N3 stage (P < 0.005), in comparison with the healthy controls. In addition, the cross-within variation of the β frequency band across all sleep stages were significantly lower in the obstructive sleep apnea hypopnea syndrome group than in the healthy controls (P < 0.05). What is more, the posterior-anterior information flowin the β frequency band of REM stage was significantly higher in mild obstructive sleep apnea hypopnea syndrome children than in the healthy controls (P < 0.05). These findings may serve as potential biomarkers for obstructive sleep apnea hypopnea syndrome in children and provide new insights into the pathophysiological mechanisms.

Defining Age-related OSA Features in Robin Sequence Using Polysomnographic-based Analyses of Respiratory Arousal Responses and Gas-exchange Parameters

INTRODUCTION

Robin sequence (RS) is a leading cause of obstructive sleep apnea (OSA) in newborns. Most studies have focused on understanding anatomic factors leading to OSA and changes in apnea-hypopnea index (AHI) on polysomnography (PSG) beyond the neonatal period. This study aims to define age-related OSA features between patients with RS, without RS and healthy controls using PSG-based analyses of respiratory arousal responses and gas-exchange parameters.

DESIGN

Retrospective comparison of PSG features in a total of 48 children encompassing three groups: (a) infants with RS (n = 24, <1-year old), (b) non-RS older children (1-2 years old) with severe OSA (obstructive AHI (OAHI) of ≥10 events; n = 12), and (c) control infants and children (0-2 years old) without sleep apnea (OAHI ≤1.5/h, n = 12). We examined OSA sleep-stage specific and position-specific indexes, and the relationship between OSA severity and respiratory arousal indexes (OAHI/respiratory arousal indexes).

RESULTS

OSA sleep-stage specific indexes (rapid eye movement [REM] vs non-REM[NREM]) as well as position-specific indexes (supine vs nonsupine) were similar in individuals with and without RS. Relative to the non-RS groups, infants with RS have more sustained hypoxemia (time with SpO₂ < 90%) and reduced arousal responses to OSA demonstrated by higher OAHI/respiratory arousal indexes. OAHI/respiratory arousal indexes significantly correlated with the severity of hypoxemia in infants with RS.

CONCLUSION

Infants with RS and OSA show reduced arousal responses to apneic events, which correlates with higher hypoxemia severity. OAHI/respiratory arousal indexes in RS may identify high-risk individuals with upper airway obstruction and reduced arousal protective responses.

Comparison of polysomnographic characteristics between low birthweight and normal birthweight children in the Northern Territory of Australia: A case-control study

OBJECTIVES

To describe the sleep architecture of pediatric patients according to whether they were born low birthweight (birthweight <2500 g, LBW) or normal birthweight (birthweight >2500 g).

DESIGN

Case control study.

SETTING

Pediatric sleep laboratory in the Northern Territory of Australia during a 5-year study period (2015- 2020).

PARTICIPANTS

Pediatric patients (aged <18 years) referred to the specialist sleep service for assessment of clinically suspected sleep disorders.

MEASUREMENTS

Sleep onset latency, rapid eye movement (REM) sleep latency, wake time after sleep onset, total sleep time, sleep efficiency, non-rapid eye movement stages N1/N2/N3, and REM sleep duration, total/spontaneous/respiratory/limb related arousal indexes, total/non-rapid eye movement/REM obstructive apnea-hypopnea index and oxygen saturation.

RESULTS

One hundred and seventy-two pediatric patients had birthweight data available of whom 19 were LBW. LBW patients showed significantly greater sleep disruption and higher prevalence of poor sleepers (<80% efficiency). In multivariate regression models, increasing birthweight was associated with significantly greater sleep efficiency and total sleep time. After accounting for gestational age LBW was associated with increased odds of obstructive sleep apnea.

CONCLUSIONS

Among pediatric patients LBW is associated with increased sleep disruption and reduced sleep efficiency. This is attenuated by gestational age, though both gestational age and LBW significantly influence odds of obstructive sleep apnea. This sleep health deficit may contribute to development of chronic disease in this vulnerable population, and should be monitored to provide avenues for early intervention.

Increased behavioral problems in children with sleep-disordered breathing

Background

Healthy sleep is essential for the cognitive, behavioral and emotional development of children. Therefore, this study aimed to assess the behavioral consequences of sleep disturbances by examining children with sleep-disordered breathing compared with control participants.

Methods

Seventy-eight children with SDB (average age: 6.7 years (SD = 1.83); 61 had OSA and 17 had primary snoring) and 156 control subjects (average age: 6.57 years (SD = 1.46) participated in the study. We matched the groups in age (t(232) = 0.578, p = 0.564) and gender (χ²(1) = 2.192, p = 0.139). In the SDB group, the average Apnea–Hypopnea Index was 3.44 event/h (SD = 4.00), the average desaturation level was 87.37% (SD = 6.91). Parent-report rating scales were used to measure the children’s daytime behavior including Attention Deficit Hyperactivity Disorder Rating Scale, Strengths and Difficulties Questionnaire, and Child Behavior Checklist.

Results

Our results showed that children with SDB exhibited a higher level of inattentiveness and hyperactive behavior. Furthermore, the SDB group demonstrated more internalizing (anxiety, depression, somatic complaints, social problems) (p < 0.001) and externalizing (aggressive and rule-breaking behavior) problems compared with children without SDB, irrespective of severity.

Conclusions

Based on our findings we supposed that snoring and mild OSA had a risk for developing behavioral and emotional dysfunctions as much as moderate-severe OSA. Therefore, clinical research and practice need to focus more on the accurate assessment and treatment of sleep disturbances in childhood, particularly primary snoring, and mild obstructive sleep apnea.

Dynamic regional homogeneity alterations and cognitive impairment in patients with moderate and severe obstructive sleep apnea

Background and purpose

Previous studies have found that abnormal local spontaneous brain activity in patients with obstructive sleep apnea (OSA) was associated with cognitive impairment, and dynamic functional connections can capture the time changes of functional connections during magnetic resonance imaging acquisition. The purpose of this study was to investigate the dynamic characteristics of regional brain connectivity and its relationship with cognitive function in patients with OSA and to explore whether the dynamic changes can be used to distinguish them from healthy controls (HCs).

Methods

Seventy-nine moderate and severe male OSA patients without any treatment and 84 HCs with similar age and education were recruited, and clinical data and resting functional magnetic resonance imaging data were collected. The dynamic regional homogeneity (dReHo) was calculated using a sliding window technique, and a double-sample t-test was used to test the difference in the dReHo map between OSA patients and HCs. We explored the relationship between dReHo and clinical and cognitive function in OSA patients using Pearson correlation analysis. A support vector machine was used to classify the OSA patients and HCs based on abnormal dReHo.

Result

Compared with HCs, OSA patients exhibited higher dReHo values in the right medial frontal gyrus and significantly lower dReHo values in the right putamen, right superior temporal gyrus, right cingulate gyrus, left insula and left precuneus. The correlation analysis showed that the abnormal dReHo values in multiple brain regions in patients with OSA were significantly correlated with nadir oxygen saturation, the oxygen depletion index, sleep period time, and Montreal cognitive assessment score. The support vector machine classification accuracy based on the dReHo difference in brain regions was 81.60%, precision was 81.01%, sensitivity was 81.01%, specificity was 82.14%, and area under the curve was 0.89.

Conclusion

The results of this study suggested that there was abnormal dynamic regional spontaneous brain activity in patients with OSA, which was related to clinical and cognitive evaluation and can be used to distinguish OSA patients from HCs. The dReHo is a potential objective neuroimaging marker for patients with OSA that can further the understanding of the neuropathological mechanism of patients with OSA.

Neurocognitive Consequences in Children with Sleep Disordered Breathing: Who Is at Risk?

Sleep-disordered breathing (SDB) is a prevalent disease in children characterized by snoring and narrowing of the upper airway leading to gas exchange abnormalities during sleep as well as sleep fragmentation. SDB has been consistently associated with problematic behaviors and adverse neurocognitive consequences in children but causality and determinants of susceptibility remain incompletely defined. Since the 1990s several studies have enlightened these associations and consistently reported poorer academic performance, lower scores on neurocognitive tests, and behavioral abnormalities in children suffering from SDB. However, not all children with SDB develop such consequences, and severity of SDB based on standard diagnostic indices has often failed to discriminate among those children with or without neurocognitive risk. Accordingly, a search for discovery of markers and clinically useful tools that can detect those children at risk for developing cognitive and behavioral deficits has been ongoing. Here, we review the advances in this field and the search for possible detection approaches and unique phenotypes of children with SDB who are at greater risk of developing neurocognitive consequences.

Serum neurofilament light reflects cognitive dysfunctions in children with obstructive sleep apnea

Background

In children, obstructive sleep apnea (OSA) can cause cognitive dysfunctions. Amyloid-beta and tau are elevated in OSA. Neurofilament light (NfL) is a marker of neuro-axonal damage, but there are no reports of NfL for OSA. The objective was to investigate the serum levels of NfL and tau in children with or without OSA and explore their relationship with cognitive dysfunctions caused by OSA.

Methods

This retrospective case–control study included children diagnosed with adenoid tonsil hypertrophy from July 2017 to September 2019 at the Second Affiliated Hospital of Xi’an Jiaotong University. Correlations between cognitive scores and tau and NfL were examined.

Results

Fifty-six OSA and 49 non-OSA children were included. The serum NfL levels were higher in the OSA group (31.68 (27.29–36.07) pg/ml) than in the non-OSA group (19.13 (17.32–20.95) pg/ml) (P < 0.001). Moreover, NfL was correlated with the course of the disease, apnea–hypopnea index (AHI), obstructive apnea index (OAI), obstructive apnea–hypopnea index (OAHI), average oxygen saturation (SaO₂), respiratory arousal index (RAI), and cognitive dysfunctions evaluated by the Chinese Wechsler Intelligence Scale for Children (C-WISC) (all P < 0.05). The area under the receiver operating characteristics curve (AUC) of NfL was 0.816 (95%CI: 0.736–0.897). Multiple regression analysis revealed that NfL was significantly associated with verbal intelligence quotient (VIQ), performance intelligence quotient (PIQ) and full-scale intelligence quotient (FIQ) (P < 0.001, respectively).

Conclusions

Serum NfL levels are associated with the severity of cognitive dysfunctions in children diagnosed with adenoid tonsil hypertrophy and might be a candidate noninvasive, objective marker to identify cognitive dysfunctions in children with OSA.

Altered cortical structure network in children with obstructive sleep apnea

STUDY OBJECTIVES

Obstructive sleep apnea (OSA) is characterized by recurrent airway collapse during sleep, resulting in intermittent hypoxia and sleep fragmentation that may contribute to alternations in brain structure and function. We hypothesized that OSA in children reorganizes and alters cortical structure, which can cause changes in cortical thickness correlation between brain regions across subjects.

METHODS

We constructed cortical structure networks based on cortical thickness measurements from 41 controls (age 15.54 ± 1.66 years, male 19) and 50 children with OSA (age 15.32 ± 1.65 years, male 29). The global (clustering coefficient [CC], path length, and small-worldness) and regional (nodal betweenness centrality, NBC) network properties and hub region distributions were examined between groups.

RESULTS

We found increased CCs in OSA compared to controls across a wide range of network densities (p-value < .05) and lower NBC area under the curve in left caudal anterior cingulate, left caudal middle frontal, left fusiform, left transverse temporal, right pars opercularis, and right precentral gyri (p-value < .05). In addition, while most of the hub regions were the same between groups, the OSA group had fewer hub regions and a different hub distribution compared to controls.

CONCLUSIONS

Our findings suggest that children with OSA exhibit altered global and regional network characteristics compared to healthy controls. Our approach to the investigation of cortical structure in children with OSA could prove useful in understanding the etiology of OSA-related brain functional disorders.

Neurobehavioral morbidity of pediatric mild sleep-disordered breathing and obstructive sleep apnea

STUDY OBJECTIVES

Obstructive sleep apnea is associated with neurobehavioral dysfunction, but the relationship between disease severity as measured by the apnea-hypopnea index and neurobehavioral morbidity is unclear. The objective of our study is to compare the neurobehavioral morbidity of mild sleep-disordered breathing versus obstructive sleep apnea.

METHODS

Children 3-12 years old recruited for mild sleep-disordered breathing (snoring with obstructive apnea-hypopnea index < 3) into the Pediatric Adenotonsillectomy Trial for Snoring were compared to children 5-9 years old recruited for obstructive sleep apnea (obstructive apnea-hypopnea 2-30) into the Childhood Adenotonsillectomy Trial. Baseline demographic, polysomnographic, and neurobehavioral outcomes were compared using univariable and multivariable analysis.

RESULTS

The sample included 453 participants with obstructive sleep apnea (median obstructive apnea-hypopnea index 5.7) and 459 participants with mild sleep-disordered breathing (median obstructive apnea-hypopnea index 0.5). By polysomnography, participants with obstructive sleep apnea had poorer sleep efficiency and more arousals. Children with mild sleep-disordered breathing had more abnormal executive function scores (adjusted odds ratio 1.96, 95% CI 1.30-2.94) compared to children with obstructive sleep apnea. There were also elevated Conners scores for inattention (adjusted odds ratio 3.16, CI 1.98-5.02) and hyperactivity (adjusted odds ratio 2.82, CI 1.83-4.34) in children recruited for mild sleep-disordered breathing.

CONCLUSIONS

Abnormal executive function, inattention, and hyperactivity were more common in symptomatic children recruited into a trial for mild sleep-disordered breathing compared to children recruited into a trial for obstructive sleep apnea. Young, snoring children with only minimally elevated apnea-hypopnea levels may still be at risk for deficits in executive function and attention.

TRIAL REGISTRATION

Pediatric Adenotonsillectomy for Snoring (PATS), NCT02562040; Childhood Adenotonsillectomy Trial (CHAT), NCT00560859.

Behavioral, neurocognitive, polysomnographic and cardiometabolic profiles associated with obstructive sleep apnea in adolescents with ADHD

BACKGROUND

A high comorbidity between attention-deficit/hyperactivity disorder (ADHD) and obstructive sleep apnea (OSA) as well as similar impairments across neurobehavioral outcomes has been described in children. However, there is a paucity of research examining the comorbidity of these two disorders in adolescents. This study examined the association of OSA with sleep, neurobehavioral, and cardiometabolic outcomes in adolescents with ADHD from the general population.

METHODS

421 adolescents (16.9 ± 2.3 years, 53.9% male) underwent 9-hr polysomnography, neurobehavioral, and physical evaluation. ADHD was ascertained by a parent-or-self-report of a lifetime diagnosis/treatment of ADHD. OSA was defined as an apnea hypopnea index of ≥2 events/hour. Groups of controls (n = 208), OSA-alone (n = 115), ADHD-alone (n = 54), and ADHD+OSA (n = 44) were studied. Multivariable-adjusted general linear models tested group differences in PSG parameters, neurobehavioral, and cardiometabolic outcomes after controlling for sex, race/ethnicity, age, and/or body mass index percentile.

RESULTS

The ADHD+OSA group had significantly longer sleep onset latency, shorter total sleep time, lower sleep efficiency, and higher percent of stage 1 sleep, as compared with all other groups, however, these differences were diminished by excluding adolescents on psychoactive medication. The ADHD-alone group showed significantly higher periodic limb movements than controls. The ADHD+OSA and ADHD-alone groups did not significantly differ on any measure of neurocognitive or behavioral functioning. The ADHD+OSA and OSA-alone groups showed significantly worse cardiometabolic and inflammatory biomarkers when compared to controls or the ADHD-alone, but did not significantly differ between each other.

CONCLUSIONS

Adolescents with a diagnosis ADHD+OSA showed phenotypic risk factors for OSA (i.e., overweight/obesity, visceral adiposity, metabolic syndrome, and inflammation) but not worse neurobehavioral outcomes when compared with ADHD-alone. While comorbidity is possible, these data support that adolescents with a suspicion of ADHD should be screened for OSA, before a diagnosis is reached and psychoactive medication initiated.

Does sleep-disordered breathing add to impairments in academic performance and brain structure usually observed in children with overweight/obesity?

Approximately 4-11% of children suffer from sleep-disordered breathing (SDB), and children with obesity are at increased risk. Both obesity and SDB have been separately associated with poorer brain health, yet whether SDB severity affects brain health in children with obesity remains unanswered. This study aimed to examine associations of SDB severity with academic performance and brain structure (i.e., total brain and gray and white matter volumes and gray matter volume in the hippocampus) in children with overweight/obesity. One hundred nine children aged 8-12 years with overweight/obesity were included. SDB severity and its subscales (i.e., snoring, daytime sleepiness, and inattention/hyperactivity) were evaluated via the Pediatric Sleep Questionnaire (PSQ), and academic performance was evaluated with the Woodcock-Muñoz standardized test and school grades. Brain structure was assessed by magnetic resonance imaging. SDB severity was not associated with academic performance measured by the standardized test (all |β|> 0.160, P > 0.076), yet it was associated with the school grade point average (β = -0.226, P = 0.007) and natural and social science grades (β = -0.269, P = 0.024). Intention/hyperactivity seemed to drive these associations. No associations were found between SDB severity and the remaining school grades (all β < -0.188, P > 0.065) or brain volumes (all P > 0.05).

CONCLUSION

Our study shows that SDB severity was associated with lower school grades, yet it was not associated with the standardized measurement of academic performance or with brain volumes in children with overweight/obesity. SDB severity may add to academic problems in children beyond the effects contributed by overweight/obesity status alone.

WHAT IS KNOWN

• Sleep-disordered breathing (SDB) may affect brain structure and academic performance in children. • Children with overweight/obesity are at higher risk for the development of SDB, yet the comorbid obesity-SDB relationship with brain health has not been investigated thus far.

WHAT IS NEW

• To our knowledge, this is the first study examining the associations of comorbid obesity-SDB severity with brain volumes and academic performance in children. • SDB symptoms may adversely affect academic performance at school in children with overweight/obesity, beyond the effects of weight status alone.

Advantages and disadvantages of mandibular distraction in Robin sequence

Robin sequence (RS) is diagnosed in infants born with micrognathia, glossoptosis and varying degrees of upper airway obstruction (UAO). Due to the variable levels of hypoxia, severe breathing and feeding problems can occur. Treatment is determined by clinical severity, ranging from conservative interventions for mild cases to surgical interventions for severe cases. Mandibular distraction osteogenesis (MDO) is a surgical technique that gradually lengthens the mandible after an osteotomy by using an internal or external distraction device, directly correcting the micrognathia. This review will focus on advantages and disadvantages of mandibular distraction in infants with RS.

Analgesia and patient comfort after enhanced recovery after surgery in uvulopalatopharyngoplasty: a randomised controlled pilot study

Background

Uvulopalatopharyngoplasty(UPPP) is the most prevalent surgical treatment of obstructive sleep apnea, but postoperative pharyngeal pain may affect patient comfort. The enhanced recovery after surgery pathway has been proved beneficial to many types of surgery but not to UPPP yet. The aim of this pilot study was to preliminarily standrize an enhanced recovery after surgery protocol for UPPP, to assess whether it has positive effects on reducing postoperative pharyngeal pain and improving patient comfort, and to test its feasibility for an international multicentre study.

Methods

This randomised controlled study analysed 116 patients with obstructive sleep apnoea (OSA) who were undergoing UPPP in a single tertiary care hospital. They were randomly divided according to treatment: the ERAS group (those who received ERAS treatment) and the control group (those who received traditional treatment). Ninety-five patients completed the assessment (ERAS group, 59 patients; control group, 36 patients). Pharyngeal pain and patient comfort were evaluated using a visual analogue scale (VAS) at 30 min and at 6, 12, 24 and 48 h after UPPP. Complications, hospitalisation duration, and hospital cost were recorded.

Results

The VAS scores for resting pain and swallowing pain were significantly lower in the ERAS group than those in the control group at 30 min and at 6, 12, 24 and 48 h after surgery. Patient comfort was improved in the ERAS group. The hospitalisation duration and cost were comparable between the groups. The incidence of complications showed an increasing trend in the ERAS group.

Conclusion

The ERAS protocol significantly relieved pharyngeal pain after UPPP and improved comfort in patients with OSA, which showed the prospect for an larger study. Meanwhile a potential increase of post-operative complications in the ERAS group should be noticed.

Trial registration

Chinese Clinical Trial Registry (23/09/2018, ChiCTR1800018537)

Reduced Tongue Mobility: An Unrecognised Risk Factor of Childhood Obstructive Sleep Apnoea

STUDY OBJECTIVES

Childhood obstructive sleep apnoea (OSA) is an important and prevalent disease. A short lingual frenulum is a risk factor for OSA, but whether tongue mobility also plays a role in OSA aetiology remains unknown. This study aimed to examine tongue mobility in children with and without OSA. We hypothesized that reduced tongue mobility was associated with OSA. We also evaluated the relationship between tongue mobility and craniofacial profile.

METHODS

This was a cross-sectional case-control study. Prepubertal Chinese children aged 5-12 years, suspected to have OSA were recruited from our sleep disorder clinic. All subjects underwent overnight polysomnography (PSG). The lingual frenulum was evaluated based on tongue mobility and free tongue length. Craniofacial measurements were assessed by lateral cephalometry.

RESULTS

Eighty-two subjects (mean age: 8.32 ± 1.70 years, 57 males) were recruited. The mean tongue mobility was 58.2 (±19)% and 67.4 (±15)% (p=0.019) in subjects with and without OSA, respectively. Tongue mobility was inversely correlated with OAHI (r=-0.218, p=0.049). In multivariate logistic regression, low tongue mobility was independently associated with a higher risk of OSA after adjustment for age, sex, BMI z-score, presence of large tonsils and turbinates and nocturnal oral breathing (odds ratio=3.65, 95% CI= 1.22-11.8). Tongue mobility was found to correlate with the cranial base angle (Ba-S-N) (r=0.262, p=0.018), which determines the relative position of the mandible.

CONCLUSIONS

In pre-pubertal children, reduced tongue mobility is associated with the occurrence and severity of OSA. Assessing tongue mobility is recommended in childhood OSA management.

Brain function in children with obstructive sleep apnea: a resting-state fMRI study

OBJECTIVE

To explore the neural difference between children with obstructive sleep apnea (OSA) and healthy controls, together with the relation between this difference and cognitive dysfunction of children with OSA.

METHODS

Twenty children with OSA (7.2 ± 3.1 years, apnea hypopnea index (AHI): 16.5 ± 16.6 events/h) and 29 healthy controls (7.7 ± 2.8 years, AHI: 1.7 ± 1.2 events/h) were recruited and matched with age, gender, and handedness. All children underwent resting-state fMRI (rs-fMRI) and T1-wighted imaging. Some children were sedated for MRI scanning. We compared amplitude of low frequency fluctuation (ALFF) and regional homogeneity (ReHo) of children with OSA with those of healthy controls. During resting-state, the former reflects the intensity of the spontaneous neural activities, whereas the latter reflects temporal similarity of the spontaneous neural activities within a local brain region. Pearson correlation analysis was performed between these features of rs-fMRI and cognitive scores among children with OSA.

RESULTS

Compared with controls, children with OSA showed decreased ALFF in the left angular gyrus but increased ALFF in the right insula, and decreased ReHo in the left medial superior frontal gyrus, right lingual gyrus, and left precuneus. Additionally, among children with OSA, the ReHo value in the right lingual gyrus was negatively correlated with FIQ and VIQ, whereas that in the left medial superior frontal gyrus was positively correlated with VIQ.

CONCLUSIONS

Children with OSA presented abnormal neural activities in some brain regions and impaired cognitive functions with the former possibly being the neural mechanism of the latter.

Sleep, cognition and executive functioning in young children with cerebral palsy

Children with cerebral palsy (CP) are at higher risk for sleep disturbances than their typically developing peers. In typically developing young children, lack of sufficient sleep results in deficits in cognition, behavior and executive functioning. Unfortunately, research on sleep in infancy rarely focuses on children with neurodevelopmental disabilities. Studies of older children with CP demonstrate that roughly half of children with CP have a sleep disorder, though screening for sleep disorders in children with CP is not routinely performed. Given the high prevalence of sleep abnormalities in older children with CP and the resulting adverse effects on functioning, understanding sleep derangements and how they affect cognition and executive functioning in these children at earlier ages is critical. In this chapter, we present the state of the evidence for sleep characteristics, cognition and executive functions for infants and toddlers 0-3years old with CP.

Disease characteristics and neuropathological changes associated with cognitive dysfunction in obstructive sleep apnea

Obstructive sleep apnea (OSA) is a common sleep-disordered breathing disease that often leads to many comorbidities (e.g., cognitive dysfunction), which adversely affect the quality of life for patients with OSA. Thus far, the underlying mechanisms of this dysfunction remain unclear. Many studies have focused on OSA-related characteristics, including intermittent hypoxemia and sleep fragmentation. There is increasing emphasis on neuroimaging studies to explore underlying relationships between neuropathological changes and cognitive dysfunction. This article reviews recent research progress concerning cognitive dysfunction associated with OSA to reveal potential mechanisms that contribute to this dysfunction.

Aberrant Hippocampal Network Connectivity Is Associated With Neurocognitive Dysfunction in Patients With Moderate and Severe Obstructive Sleep Apnea

Objectives: This work aims to explore the changes of functional connectivity (FC) within the hippocampus network in patients with moderate and severe obstructive sleep apnea (OSA) and its correlation with neurocognitive dysfunction to explore the potential neurophysiological mechanism. Methods: A total of 32 treatment-naïve patients with moderate or severe OSA and 26 healthy controls (HCs), matched in age, gender, and education, underwent the evaluations of Epworth Sleep Scale, neurocognitive function, full-night polysomnography, and resting-state functional magnetic resonance imaging. The FC map of the hippocampus to other brain areas was compared among 15 OSA patients and 15 HCs with little head motion. Finally, the correlation between hippocampus FC strength and respiratory sleep parameters and neurocognitive assessments was analyzed. Results: Compared with HCs, the right hippocampus showed a significantly decreased FC with the bilateral insular lobe, right thalamus, and right anterior cingulate gyrus (ACG) and an increased FC with the right superior and middle temporal gyrus, left posterior cingulate gyrus, and left angular gyrus in the patients with OSA. The left hippocampus presented a significantly decreased FC with the left anterior cerebellum in patients with OSA. In addition, the aberrant right hippocampal FC with the right ACG was significantly correlated with disease severity and disrupted sleep architecture in the OSA group. Furthermore, after adjusting the related confounding factors, the FC strength between the right hippocampus, right insular lobe, and right thalamus was positively associated with the scores of Stroop Color-Word Test (SCWT) or Hopkins Verbal Learning Test-Revised (HVLT-R), while the FC between the right hippocampus and the right middle temporal gyrus was negatively correlated with the scores of HVLT-R. The right hippocampus FC with right superior temporal gyrus, left angular gyrus, and ACG were all negatively related to the scores of the symbol coding test (r = -0.642, p = 0.045; r = -0.638, p = 0.047; r = -0.753, p = 0.012), respectively. The FC between the left hippocampal and the left anterior cerebellar lobe showed a positive relationship with the scores of HVLT-R (r = 0.757, p = 0.011) and CPT-3D (r = -0.801, p = 0.005). Conclusion: The hippocampus presented abnormal FC with the cerebral and cerebellar regions extensively in OSA, and the correlation between abnormal hippocampal network FC and neurocognitive dysfunction in OSA suggests a promising insight to explore the potential biomarker and pathophysiologic mechanism of neurocognitive dysfunction of OSA.

Volumetric brain magnetic resonance imaging analysis in children with obstructive sleep apnea

OBJECTIVES

Pediatric Obstructive Sleep Apnea (OSA) is associated with neurocognitive deficits. Cerebral structural alterations in the frontal cortex, cerebellum, and hippocampus have been reported in adult OSA patients. These brain areas are important for executive functioning, motor regulation of breathing, and memory function, respectively. Corresponding evidence comparing cerebral structures in pediatric OSA patients is limited. The objective of this study is to investigate MRI differences in cortical thickness and cortical volume in children with and without OSA.

STUDY DESIGN

Prospective, single institutional case-control study.

METHODS

Forty-five children were recruited at a pediatric tertiary care center (27 with OSA; mean age 9.9 ± 1.9 years, and 18 controls; mean age 10.5 ± 1.0 years). The OSA group underwent magnetic resonance imaging (MRI), polysomnography (PSG) and completed the Pediatric Daytime Sleepiness Scale (PDSS) and the Child's Sleep Habits Questionnaire (CSHQ). High-resolution T1-weighted MRI was utilized to examine cortical thickness and gray and white matter volume in children with OSA compared to a healthy group of demographically-comparable children without OSA selected from a pre-existing MRI dataset.

RESULTS

Children with OSA showed multiple regions of cortical thinning primarily in the left hemisphere. Reduced gray matter (GM) volume was noted in the OSA group in multiple frontal regions of the left hemisphere (superior frontal, rostral medial frontal, and caudal medial frontal regions). Reduced white matter (WM) volume in both the left and right hemisphere was observed in regions of the frontal, parietal, and occipital lobes in children with OSA.

CONCLUSION

This study noted differences in cortical thickness and GM and WM regional brain volumes in children with OSA. These findings are consistent with other pediatric studies, which also report differences between healthy children and those with OSA. We found that the severity of OSA does not correlate with the extent of MRI alterations.

Effects of obstructive sleep apnoea severity on neurocognitive and brain white matter alterations in children according to sex: a tract-based spatial statistics study

OBJECTIVES

To investigate alterations in neurocognitive, attention, paediatric sleep questionnaire (PSQ) scores and whole brain white matter (WM) integrity between children with mild and severe obstructive sleep apnoea (OSA) according to sex and whether these changes are associated with OSA severity.

METHODS

Fifty-seven children (36 males and 21 females) diagnosed with OSA were recruited for this study. Children of both sexes were divided into mild (male-MG, female-MG) and severe (male-SG, female-SG) groups according to OSA severity. Polysomnography (PSG), neurocognitive, attention and PSQ tests were compared between groups by one-way samples analysis of variance (ANOVA) F test. Diffusion tensor imaging (DTI) was scanned using a 3T GE MRI scanner and analysed by Tract-based Spatial Statistics (TBSS). Spearman correlation was calculated between DTI Eigenvalues and clinical characteristics.

RESULTS

Compared to mild OSA patients, severe OSA patients presented greater severity of obstructive apnoea hypopnea index (OAHI), neurocognition, PSQ and attention tests in both male and female patients. Brain WM integrity in the male-SG, compared to the male-MG, demonstrated significantly reduced fractional anisotropy (FA) values in the right middle frontal gyrus and the right frontal sub-gyral regions and increased axial diffusivity (AD) values in the right inferior frontal gyrus, left parietal angular gyrus and sub-gyral regions, while no differences were found between the female-MG and female-SG. Alterations in male-SG brain regions were observably correlated with severity in male OSA patients.

CONCLUSIONS

The integrity of WM, which regulates autonomic, cognitive, and attention functions, is impaired in male, but not female, children with severe OSA.

Sleep and Early Brain Development

The early years of life are characterized by dramatic developmental changes. Within this important time period lies the transition from newborn to childhood. Sleep is one of the primary activities of the brain during early development and plays an important role in healthy cognitive and psychosocial development in early life. This paper will first review the normal sleep characteristics and their development in neonates and children, including architecture of sleep, development of a healthy sleep rhythm in early childhood, sleep recommendations and cultural disparity, as well as important factors for establishing a healthy sleep pattern during the first years of life, such as regular and consistent bedtime routine, safe and comfortable sleep environment, and appropriate sleep onset associations. This paper then provides recent updates of evidence of the effects of sleep on early brain development, particularly on learning and memory, emotional regulation, and general cognitive development through behavioral and neurophysiological studies. As regards the mechanism, many experimental sleep deprivation studies in animals and adults have attempted to explain the underlying mechanisms of sleep on cognition and the emotional brain. Future studies are expected to delineate the effects of sleep on brain structural and functional networks in the developing brain with the marked development of image acquisition approaches and the novel analysis tools for infants and young children in recent years.

Pediatric obstructive sleep apnea: Preoperative and neurocognitive considerations for perioperative management

Obstructive sleep apnea (OSA) affects up to 7.5% of the pediatric population and is associated with a variety of behavioral and neurocognitive sequelae. Prompt diagnosis and treatment is critical to halting and potentially reversing these changes. Depending on the severity of the OSA and comorbid conditions, different treatment paradigms can be pursued, each of which has its own unique risk:benefit ratio. Adenotonsillectomy is first-line recommended surgical treatment for pediatric OSA. However, it carries its own perioperative risks and the decision regarding surgical timing is therefore made in the context of procedural risk versus patient benefit. This article presents the seminal perioperative and neurocognitive risks from pediatric OSA to aid with perioperative management.

Beyond the growth delay in children with sleep-related breathing disorders: a systematic review

INTRODUCTION

The availability of high-quality studies on the association between sleep-disordered breathing in children and delayed growth associated with the hormonal profile recorded before surgery and at follow-up is limited.

EVIDENCE ACQUISITION

Medline PubMed, Scopus and WebOfScience databases were searched for relevant publications published between January 2008 to January 2020 and a total of 261 potentially eligible studies were identified.

EVIDENCE SYNTHESIS

Following review 19 papers were eligible for inclusion: seven reported a significant postsurgical increase in growth regardless of initial weight status, type of surgery, type of study design, and length of follow-up period. The only high-quality study was a randomized controlled trial that found an increased risk of obstructive sleep apnea syndrome relapse in overweight children. Twelve studies reported the significant increase in growth parameters showing that IGF-1, IGFBP-3, and ghrelin may boost growth after surgery.

CONCLUSIONS

The current systematic review demonstrates a scarcity of high-quality studies on growth delay in children with sleep-disordered breathing. Significant catch-up growth after surgery in the short term and changes in IGF-1, IGFBP-3, ghrelin, and leptin levels has been reported in most published studies.

Patterns of brain structural alteration in COPD with different levels of pulmonary function impairment and its association with cognitive deficits

Background

To explore patterns of brain structural alteration in chronic obstructive pulmonary disease (COPD) patients with different levels of lung function impairment and the associations of those patterns with cognitive functional deficits using voxel-based morphometry (VBM) and tract-based spatial statistics (TBSS) analyses based on high-resolution structural MRI and diffusion tensor imaging (DTI).

Methods

A total of 115 right-handed participants (26 severe, 29 moderate, and 29 mild COPD patients and a comparison group of 31 individuals without COPD) completed tests of cognitive (Montreal Cognitive Assessment [MoCA]) and pulmonary function (forced expiratory volume in 1 s [FEV1]) and underwent MRI scanning. VBM and TBSS analyses were used to identify changes in grey matter density (GMD) and white matter (WM) integrity in COPD patients. In addition, correlation analyses between these imaging parameter changes and cognitive and pulmonary functional impairments were performed.

Results

There was no significant difference in brain structure between the comparison groups and the mild COPD patients. Patients with moderate COPD had atrophy of the left middle frontal gyrus and right opercular part/triangular part of the inferior frontal gyrus, and WM changes were present mainly in the superior and posterior corona radiata, corpus callosum and cingulum. Patients with severe COPD exhibited the most extensive changes in GMD and WM. Some grey matter (GM) and WM changes were correlated with MoCA scores and FEV1.

Conclusions

These findings suggest that patients with COPD exhibit progressive structural impairments in both the GM and the WM, along with impaired levels of lung function, highlighting the importance of early clinical interventions.

Emotional Intelligence in Children with Severe Sleep-Related Breathing Disorders

BACKGROUND

Obstructive sleep apnea syndrome (OSAS) affects up to 4% of a pediatric population, with many comorbidities in the medium-long term. Functional alterations in the prefrontal cortex (PFC) may explain why OSAS impacts aspects such as executive functions, memory, motor control, attention, visual-spatial skills, learning, and mood regulation. Emotional intelligence (EI) is a complex neuropsychological function that could be impaired in many clinical conditions.

PURPOSE

The aim of the study is to evaluate the difference in emotional intelligence skills among children with OSAS and healthy subjects (nOSAS).

METHODS

129 children (72 males; mean age 7.64 ± 1.98 years) affected by OSAS were compared to 264 non-OSAS (nOSAS) children (138 males; mean age 7.98 ± 2.13) similar for gender, age, and socioeconomic status. In order to assess the emotional quotient, the Bar-On Emotional Quotient Inventory: Youth Version (EQ-i:YV) was used.

RESULTS

The comparison for means and standard deviation between OSAS children and nOSAS children for EQ-i:YV scores showed significant differences for Interpersonal, Adaptability, and Stress Management scales and EQ Total score.

CONCLUSIONS

Our findings highlighted the role of intermittent hypoxia in the genesis of the effects of sleep-related respiratory disorders, which involves also aspects different from physical impairments.

Age and autonomic control, but not cerebral oxygenation, are significant determinants of EEG spectral power in children

Study Objectives

Sleep 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.

Methods

One 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.

Results

There 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.

Conclusion

The 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.

Related biomarkers of neurocognitive impairment in children with obstructive sleep apnea

OBJECTIVES

Different experiment approaches have demonstrated that children with obstructive sleep apnea (OSA) exhibit neurocognitive and behavioral deficits. This review summarized the potential biomarkers of OSA-associated neurocognitive impairment in children.

METHODS

A scoping review of studies on children with OSA that evaluated the potential value of different markers in identifying neurocognitive impairment was undertaken. Additionally, the biomarkers were categorized according to the different research methods, including brain imaging studies, serological indicators and urine markers.

RESULTS

Majority of the studies that evaluated blood biomarkers, plasma insulin growth factor-1 (IGF-1) and Alzheimer's disease (AD)-related biomarkers appeared to exhibit a favorable profile, and could discriminate between OSA children with or without neurocognitive impairments. Brain imaging studies and urinary neurotransmitters could also be helpful for screening OSA cognitive morbidity in children.

CONCLUSION

Due to limited research methods available in children, the cognitive susceptibility of children with OSA has been rarely studied. The main reason for this may be the limited research methods in children. Numerous study populations of children and complex psychological tests are required, which involve major labor and costs.Multi-center prospective studies are needed to identify suitable biomarkers for the timely prediction and effective intervention to prevent neurocognitive impairment in children with OSA and to explore further opportunities in this arena.

Aberrant Interhemispheric Connectivity in Obstructive Sleep Apnea-Hypopnea Syndrome

Objective

To determine the changes in interhemispheric functional coordination in patients with obstructive sleep apnea–hypopnea syndrome (OSAHS) relative to controls, using a recently introduced method of analysis: voxel-mirrored homotopic connectivity (VMHC).

Methods

Twenty-nine patients with OSAHS and twenty-six normal sex-, age-, and education-matched controls were recruited and resting-state functional magnetic resonance imaging data were obtained. We employed VMHC to analyze the interhemispheric functional connectivity differences between groups. The z-values of alterations in VMHC in brain region were correlated with clinical characteristics.

Results

Compared with controls, patients with OSAHS had significantly higher scores for body mass index (t = 5.749, P < 0.001), apnea–hypopnea index (AHI; t = 7.706, P < 0.001), oxygen desaturation index (t = 6.041, P < 0.001), and Epworth sleepiness scale (t = 3.711, P < 0.001), but significantly lower scores on the Rey–Osterrieth complex figure test-immediate recall (t = −3.727, P < 0.05). On the same basis, the VMHC showed significant increases in bilateral calcarine cortex and precuneus. Moreover, significant, positive correlations were found in only these areas between the AHI and the VMHC change coefficients (r = 0.399, P = 0.032; r = 0.378, P = 0.043).

Conclusion

We found a memory defect in patients with OSAHS. The correlation between the abnormal VMHC and the AHI in patients with OSAHS suggested that AHI might be a key factor in cognitive dysfunction, which might offer new insights into the neural pathophysiology underlying OSAHS-related cognitive deficits.

Waking up too early - the consequences of preterm birth on sleep development

Good quality sleep of sufficient duration is vital for optimal physiological function and our health. Sleep deprivation is associated with impaired neurocognitive function and emotional control, and increases the risk for cardiometabolic diseases, obesity and cancer. Sleep develops during fetal life with the emergence of a recognisable pattern of sleep states in the preterm fetus associated with the development, maturation and connectivity within neural networks in the brain. Despite the physiological importance of sleep, surprisingly little is known about how sleep develops in individuals born preterm. Globally, an estimated 15 million babies are born preterm (<37 weeks gestation) each year, and these babies are at significant risk of neural injury and impaired brain development. This review discusses how sleep develops during fetal and neonatal life, how preterm birth impacts on sleep development to adulthood, and the factors which may contribute to impaired brain and sleep development, leading to altered neurocognitive, behavioural and motor capabilities in the infant and child. Going forward, the challenge is to identify specific risk factors for impaired sleep development in preterm babies to allow for the design of interventions that will improve the quality and quantity of sleep throughout life.

Altered Regional Brain Cortical Thickness in Pediatric Obstructive Sleep Apnea

Rationale

Obstructive sleep apnea (OSA) affects 2–5% of all children and is associated with cognitive and behavioral deficits, resulting in poor school performance. These psychological deficits may arise from brain injury, as seen in preliminary findings of lower gray matter volume among pediatric OSA patients. However, the psychological deficits in OSA are closely related to functions in the cortex, and such brain areas have not been specifically assessed. The objective was to determine whether cortical thickness, a marker of possible brain injury, is altered in children with OSA.

Methods

We examined regional brain cortical thicknesses using high-resolution T1-weighted magnetic resonance images in 16 pediatric OSA patients (8 males; mean age ± SD = 8.4 ± 1.2 years; mean apnea/hypopnea index ± SD = 11 ± 6 events/h) and 138 controls (8.3 ± 1.1 years; 62 male; 138 subjects from the NIH Pediatric MRI database) to identify cortical thickness differences in pediatric OSA subjects.

Results

Cortical thinning occurred in multiple regions including the superior frontal, ventral medial prefrontal, and superior parietal cortices. The left side showed greater thinning in the superior frontal cortex. Cortical thickening was observed in bilateral precentral gyrus, mid-to-posterior insular cortices, and left central gyrus, as well as right anterior insula cortex.

Conclusion

Changes in cortical thickness are present in children with OSA and likely indicate disruption to neural developmental processes, including maturational patterns of cortical volume increases and synaptic pruning. Regions with thicker cortices may reflect inflammation or astrocyte activation. Both the thinning and thickening associated with OSA in children may contribute to the cognitive and behavioral dysfunction frequently found in the condition.

A Meta-analysis of Voxel-based Brain Morphometry Studies in Obstructive Sleep Apnea

Gray matter (GM) anomalies may represent a critical pathology underlying obstructive sleep apnea (OSA). However, the evidence regarding their clinical relevance is inconsistent. We conducted a meta-analysis of voxel-based morphometry (VBM) studies of patients with OSA to identify their brain abnormalities. A systematic search was conducted based on PRISMA guidelines, and a meta-analysis was performed using the anisotropic effect-size-based algorithms (ASE-SDM) to quantitatively estimate regional GM changes in patients with OSA. Fifteen studies with 16 datasets comprising 353 untreated patients with OSA and 444 healthy controls were included. Our results revealed GM reductions in the bilateral anterior cingulate/paracingulate gyri (ACG/ApCG), left cerebellum (lobules IV/V and VIII), bilateral superior frontal gyrus (SFG, medial rostral part), right middle temporal gyrus (MTG), and right premotor cortex. Moreover, GM reductions in the bilateral ACG/ApCG were positively associated with body mass index (BMI) and age among patients with OSA, and GM reductions in the SFG (medial rostral part) were negatively associated with Epworth sleepiness scale (ESS) scores and sex (male). These abnormalities may represent structural brain underpinnings of neurocognitive abnormalities and respiratory-related abnormalities in OSA. In particular, this study adds to Psychoradiology, which is a promising subspecialty of clinical radiology mainly for psychiatric disorders.

Cognitive Function Among Obstructive Sleep Apnea Patients in North East Malaysia

INTRODUCTION

Obstructive sleep apnea patients may develop deficits in the cognitive domains of attention, concentration, executive function, verbal and visuospatial memory, constructional abilities, and psychomotor functioning. As cognitive performance will improve with the treatment, early screening for cognitive dysfunction should be done to prevent further deterioration.

OBJECTIVE

We aim to evaluate the cognitive function of obstructive sleep apnea patients by using the 'Mini Mental State Examination'.

METHODOLOGY

This was a cross sectional study to evaluate the cognitive function of moderate and severe obstructive sleep apnea patients with age ranged from 18 to 60 old who attended our sleep clinic. These patients were confirmed to have moderate and severe obstructive sleep apnea by Type 1 polysomnography (attended full overnight study). The age, gender and ethnicity were noted and other relevant data such as weight, height, body mass index and apnea and hypopnoea index were recorded accordingly. The cognitive function was evaluated using validated Malay version of Mini Mental State Examination which measured 5 areas of cognitive functions comprising orientation, registration, attention and calculation, word recall and language abilities, and visuospatial.

RESULTS

A total of 38 patients participated in this study. All 19 patients of moderate group and 14 patients of severe group had normal cognitive function while only 5 patients in severe group had mild cognitive function impairment. There was a statistically significant difference between the moderate group and severe group on cognitive performance (p value = 0.042).

CONCLUSIONS

Severe obstructive sleep apnea patients may have impaired cognitive function. Mini Mental State Examination is useful in the screening of cognitive function of obstructive sleep apnea patients but in normal score, more sophisticated test batteries are required as it is unable to identify in 'very minimal' or 'extremely severe' cognitive dysfunction.

Robin sequence: what the multidisciplinary approach can do

Robin sequence (RS) is a commonly encountered triad of micrognathia, glossoptosis, and airway obstruction, with or without a cleft palate. The management of airway obstruction is of paramount importance, and multiple reviews and retrospective series outline the diagnosis and treatment of RS. This article focuses on the multidisciplinary nature of RS and the specialists’ contributions and thought processes regarding the management of the RS child from birth to skeletal maturity. This review demonstrates that the care of these children extends far beyond the acute airway obstruction and that thorough monitoring and appropriate intervention are required to help them achieve optimal outcomes.

The Effects of Obstructive Sleep Apnea Syndrome on the Dentate Gyrus and Learning and Memory in Children

Obstructive sleep apnea syndrome (OSAS) is associated with intermittent hypoxia and sleep loss. In children, impairments of cognitive function are important manifestations, but the underlying pathology is unknown. We hypothesized that OSAS would affect the dentate gyrus, a hippocampal subdivision essential to neurogenesis and cognition, and that this impact would further affect cognitive function in children. In children with OSAS (n = 11) and control subjects (n = 12; age and sex matched), we performed diffusion tensor imaging and structural MRI, polysomnography, and neuropsychological assessments. We found that OSAS was associated with decreased mean diffusivity of the left dentate gyrus (p = 0.002; false discovery rate corrected; adjusting for sex, age, and body mass index), showing a large effect size (partial η² = 0.491), but not with any other structural measures across the brain. Decreased dentate gyrus mean diffusivity correlated with a higher apnea hypopnea index (Spearman's r = -0.50, p = 0.008) and a greater arousal index (r = -0.44, p = 0.017). OSAS did not significantly affect neuropsychological measures (p values >0.5); however, a lower verbal learning score correlated with lower dentate gyrus mean diffusivity (r = 0.54, p = 0.004). Path analysis demonstrated that dentate gyrus mean diffusivity mediates the impact of OSAS on verbal learning capacity. Finally, the diagnostic accuracy of a regression model based on dentate gyrus mean diffusivity reached 85.8% (cross validated). This study demonstrates a likely pathway of effects of OSAS on neurocognitive function in children, as well as potential utility of the dentate gyrus mean diffusivity as an early marker of brain pathology in children with OSAS.SIGNIFICANCE STATEMENT In this study we investigate the relationships between dentate gyrus structure, hippocampus-dependent cognition, and obstructive sleep apnea syndrome (OSAS). We demonstrate lower mean diffusivity of the dentate gyrus in children with OSAS, which correlates with a lower verbal learning and memory score. This study provides new evidence of disrupted microstructure of the dentate gyrus in children with OSAS that may help explain some of the neurocognitive deficits described in these children.

Reduced Regional Grey Matter Volumes in Pediatric Obstructive Sleep Apnea

Pediatric OSA is associated with cognitive risk. Since adult OSA manifests MRI evidence of brain injury, and animal models lead to regional neuronal losses, pediatric OSA patients may also be affected. We assessed the presence of neuronal injury, measured as regional grey matter volume, in 16 OSA children (8 male, 8.1 ± 2.2 years, AHI:11.1 ± 5.9 events/hr), and 200 control subjects (84 male, 8.2 ± 2.0 years), 191 of whom were from the NIH-Pediatric MRI database. High resolution T1-weighted whole-brain images were assessed between groups with voxel-based morphometry, using ANCOVA (covariates, age and gender; family-wise error correction, P < 0.01). Significant grey matter volume reductions appeared in OSA throughout areas of the superior frontal and prefrontal, and superior and lateral parietal cortices. Other affected sites included the brainstem, ventral medial prefrontal cortex, and superior temporal lobe, mostly on the left side. Thus, pediatric OSA subjects show extensive regionally-demarcated grey matter volume reductions in areas that control cognition and mood functions, even if such losses are apparently independent of cognitive deficits. Since OSA disease duration in our subjects is unknown, these findings may result from either delayed neuronal development, neuronal damaging processes, or a combination thereof, and could either reflect neuronal atrophy or reductions in cellular volume (neurons and glia).

Morphometry analysis of basal ganglia structures in children with obstructive sleep apnea

BACKGROUND

Obstructive sleep apnea (OSA) affects both adults and children, likely mediated by the deficits of various brain regions. The association between structural alterations in the brain and OSA syndrome have been reported in adult patients, but the corresponding evidence for OSA children is still limited.

OBJECTIVE

The proposed study aimed to investigate the structural alterations in the brain of children with OSA, with focus on basal ganglia structures.

METHODS

We recruited 25 OSA children (aged 10.3±1.5 years) and 30 healthy children (aged 10.1±1.8 years) with T1-weighted brain MRI and performed automatic segmentation of their brains. The shape alterations of the basal ganglia structures for OSA syndrome was determined by comparison of the OSA group and control group with surface-based shape analysis.

RESULTS

Differences in the morphometry of the left thalamus and the left pallidum were found between the OSA group and control group. Compared to the control group, the OSA group presented significant atrophy in the ventral posterior nucleus and the medial dorsal nucleus of the left thalamus, while regional dilation was found in both the internal and external segments of the left pallidum.

CONCLUSION

These findings identified the association between the structural deficits of the thalamus and OSA syndrome in children, which was consistent with the existing findings in OSA adults. In addition, the present study provided new insights to the distinctive pattern of structural changes of the pallidum in pediatric OSA when compared to adult OSA.