Cognitive deficits in adults with obstructive sleep apnea compared to children and adolescents

The Complex Relationship between Neuromodulators, Circadian Rhythms, and Insomnia in Patients with Obstructive Sleep Apnea

Obstructive sleep apnea (OSA) has been linked to disruptions in circadian rhythm and neurotrophin (NFT) signaling. This study explored the link between neuromodulators, chronotype, and insomnia in OSA. The participants (n = 166) underwent polysomnography (PSG) before being categorized into either the control or the OSA group. The following questionnaires were completed: Insomnia Severity Index (ISI), Epworth Sleepiness Scale, Chronotype Questionnaire (morningness-eveningness (ME), and subjective amplitude (AM). Blood samples were collected post-PSG for protein level assessment using ELISA kits for brain-derived neurotrophic factor (BDNF), proBDNF, glial-cell-line-derived neurotrophic factor, NFT3, and NFT4. Gene expression was analyzed utilizing qRT-PCR. No significant differences were found in neuromodulator levels between OSA patients and controls. The controls with insomnia exhibited elevated neuromodulator gene expression (p < 0.05). In the non-insomnia individuals, BDNF and NTF3 expression was increased in the OSA group compared to controls (p = 0.007 for both); there were no significant differences between the insomnia groups. The ISI scores positively correlated with all gene expressions in both groups, except for NTF4 in OSA (R = 0.127, p = 0.172). AM and ME were predicting factors for the ISI score and clinically significant insomnia (p < 0.05 for both groups). Compromised compensatory mechanisms in OSA may exacerbate insomnia. The correlation between chronotype and NFT expression highlights the role of circadian misalignments in sleep disruptions.

Sex differences in the association of sleep spindle density and cognitive performance among community-dwelling middle-aged and older adults with obstructive sleep apnea

Recent studies have found associations between obstructive sleep apnea and cognitive decline. The underlying mechanisms are still unclear. Here, we investigate the associations between changes in micro-architecture, specifically sleep spindles, and cognitive function in community-dwelling middle-aged and older adults, some with obstructive sleep apnea, with a focus on sex differences. A total of 125 voluntary participants (mean age 66.0 ± 6.4 years, 64 females) from a larger cohort (participants of the Brain in Motion Studies I and II) underwent 1 night of in-home polysomnography and a neuropsychological battery (sleep and cognitive testing were conducted within 2 weeks of each other). A semi-automatic computerized algorithm was used to score polysomnography data and detect spindle characteristics in non-rapid eye movement Stages 2 and 3 in both frontal and central electrodes. Based on their apnea-hypopnea index, participants were divided into those with no obstructive sleep apnea (apnea-hypopnea index < 5 per hr, n = 21), mild obstructive sleep apnea (5 ≥ apnea-hypopnea index < 15, n = 47), moderate obstructive sleep apnea (15 ≥ apnea-hypopnea index < 30, n = 34) and severe obstructive sleep apnea (apnea-hypopnea index ≥ 30, n = 23). There were no significant differences in spindle characteristics between the four obstructive sleep apnea severity groups. Spindle density and percentage of fast spindles were positively associated with some verbal fluency measures on the cognitive testing. Sex might be linked with these associations. Biological sex could play a role in the associations between spindle characteristics and some verbal fluency measures. Obstructive sleep apnea severity was not found to be a contributing factor in this non-clinical community-dwelling cohort.

Cognition and saccadic eye movement performance are impaired in chronic rhinosinusitis

BACKGROUND

Patients with chronic rhinosinusitis (CRS) can experience cognitive dysfunction. The literature on this topic mostly reflects patient-reported measurements. Our goal was to assess cognitive function in patients with CRS using objective measures, including saccadic eye movements-a behavioral response reflecting cognitive and sensory information integration that is often compromised in conditions with impaired cognition.

METHODS

Participants (N = 24 with CRS, N = 23 non-CRS healthy controls) enrolled from rhinology clinic underwent sinonasal evaluation, quality of life assessment (Sino-nasal Outcome Test 22 [SNOT-22]), and cognitive assessment with the Neuro-QOL Cognitive Function-Short Form, the Montreal Cognitive Assessment (MoCA), and recording of eye movements using video-oculography.

RESULTS

Participants with CRS were more likely to report cognitive dysfunction (Neuro-QOL; 45.8% vs. 8.7%; p = 0.005) and demonstrate mild or greater cognitive impairment (MoCA; 41.7% vs. 8.7%; p = 0.005) than controls. Additionally, participants with CRS performed worse on the MoCA overall and within the executive functioning and memory domains (all p < 0.05) and on the anti-saccade (p = 0.014) and delay saccade (p = 0.044) eye movement tasks. Poorer performance on the MoCA (r = -0.422; p = 0.003) and the anti-saccade (r = -0.347; p = 0.017) and delay saccade (r = -0.419; p = 0.004) eye movement tasks correlated with worse CRS severity according to SNOT-22 scores.

CONCLUSION

This study is the first to utilize objective eye movement assessments in addition to researcher-administered cognitive testing in patients with CRS. These patients demonstrated a high prevalence of cognitive dysfunction, most notably within executive functioning and memory domains, with the degree of dysfunction correlating with the severity of CRS.

Adaptive Functioning and Sleep Quality: Associations in Young Children with Congenital Heart Disease

Congenital heart disease (CHD) is one of today's leading birth anomalies. Children with CHD are at risk for adaptive functioning challenges. Sleep difficulties are also common in children with CHD. Indeed, sleep-disordered breathing, a common type of sleep dysfunction, is associated with increased mortality for infants with CHD. The present study examined the associations between adaptive functioning and sleep quality (i.e., duration and disruptions) in children with CHD (n = 23) compared to healthy children (n = 38). Results demonstrated associations between mean hours slept and overall adaptive functioning in the CHD group r(21) = .57, p = .005 but not in the healthy group. The CHD group demonstrated lower levels of adaptive functioning in the Conceptual, t(59) = 2.12, p = .039, Cohen's d = 0.53 and Practical, t(59) = 2.22, p = .030, Cohen's d = 0.55 domains, and overall adaptive functioning (i.e., General Adaptive Composite) nearing statistical significance in comparison to the healthy group, t(59) = 2.00, p = .051, Cohen's d = 0.51. The CHD group also demonstrated greater time awake at night, t(56) = 2.19, p = .033, Cohen's d = 0.58 and a greater instance of parent-caregiver reported snoring, χ2 (1, N = 60) = 5.25, p = .022, V = .296 than the healthy group. Further exploration of the association between adaptive functioning and sleep quality in those with CHD is required to inform clinical practice guidelines.

Sleep apnoea, gut dysbiosis and cognitive dysfunction

Sleep disorders are becoming increasingly common, and their distinct effects on physical and mental health require elaborate investigation. Gut dysbiosis (GD) has been reported in sleep-related disorders, but sleep apnoea is of particular significance because of its higher prevalence and chronicity. Cumulative evidence has suggested a link between sleep apnoea and GD. This review highlights the gut-brain communication axis that is mediated via commensal microbes and various microbiota-derived metabolites (e.g. short-chain fatty acids, lipopolysaccharide and trimethyl amine N-oxide), neurotransmitters (e.g. γ-aminobutyric acid, serotonin, glutamate and dopamine), immune cells and inflammatory mediators, as well as the vagus nerve and hypothalamic-pituitary-adrenal axis. This review also discusses the pathological role underpinning GD and altered gut bacterial populations in sleep apnoea and its related comorbid conditions, particularly cognitive dysfunction. In addition, the review examines the preclinical and clinical evidence, which suggests that prebiotics and probiotics may potentially be beneficial in sleep apnoea and its comorbidities through restoration of eubiosis or gut microbial homeostasis that regulates neural, metabolic and immune responses, as well as physiological barrier integrity via the gut-brain axis.

Linking orthodontic treatment and sleep apnea among adult Indian patients

The differences in the effects of orthodontic treatment on airway and craniocervical posture in patients with OSA (obstructive sleep apnea) having skeletal class II high-angle malocclusion is of interest. Hence, 48 individuals with OSA and skeletal class II high-angle malocclusion were chosen from among all patients in need of orthodontic therapy. Every patients had CBCT (cone beam computed tomography) taken both before and after receiving orthodontic therapy. All parameters were assessed on the lateral cephalogram from CBCT in order to assess the indices of craniocervical posture, hyoid position, skeletal and dental conditions. Parameters of upper airway (position of hyoid) showed statistically significant increase in values after orthodontic treatments. Thus, there was increase in values of dimensions of upper airway, post orthodontic treatment. Hence, orthodontic therapy help improve the upper airway morphology and craniocervical posture in patients of OSA with hyperdivergent skeletal class II malocclusion.

Respiratory Dysfunction in Alzheimer's Disease-Consequence or Underlying Cause? Applying Animal Models to the Study of Respiratory Malfunctions

Alzheimer's disease (AD) is a neurodegenerative brain disease that is the most common cause of dementia among the elderly. In addition to dementia, which is the loss of cognitive function, including thinking, remembering, and reasoning, and behavioral abilities, AD patients also experience respiratory disturbances. The most common respiratory problems observed in AD patients are pneumonia, shortness of breath, respiratory muscle weakness, and obstructive sleep apnea (OSA). The latter is considered an outcome of Alzheimer's disease and is suggested to be a causative factor. While this narrative review addresses the bidirectional relationship between obstructive sleep apnea and Alzheimer's disease and reports on existing studies describing the most common respiratory disorders found in patients with Alzheimer's disease, its main purpose is to review all currently available studies using animal models of Alzheimer's disease to study respiratory impairments. These studies on animal models of AD are few in number but are crucial for establishing mechanisms, causation, implementing potential therapies for respiratory disorders, and ultimately applying these findings to clinical practice. This review summarizes what is already known in the context of research on respiratory disorders in animal models, while pointing out directions for future research.

Knowledge and Attitudes of Obstructive Sleep Apnea among Jordanian Otolaryngologists: A Cross-Sectional Study

Obstructive sleep apnea (OSA) is a common sleep-related breathing disorder that affects almost one billion individuals worldwide. An estimated 16.8% of adults in Jordan have been diagnosed with OSA. Given the importance of management of OSA by otolaryngologists, we assessed the knowledge and attitudes of Jordanian otolaryngologists in managing OSA in adult and pediatric patients. A survey, conducted anonymously online, was sent present otolaryngology residents and specialist in Jordan, in the English language. The participants were given the OSA Knowledge and Attitude questionnaire (OSAKA, OSAKA-KIDS), which have been previously validated. Data were obtained and then analyzed via SPSS software. A total of 140 residents and specialist of otolaryngology were selected. A significant difference in OSAKA scores were found between otolaryngologists under 30 years of age and those above, with higher scores for the older age group. The proportion of specialists who 'agreed' or 'strongly agreed' they are confident in their ability to manage patients with OSA was significantly higher that junior residents (73.8% vs 33.3%; p = 0.008). More than 10 years at practice was associated with statistically significant higher levels of knowledge towards OSAKA scale (AOR = 0.09; p = 0.044). Additionally, being a senior resident was significantly associated with more knowledge towards OSAKA-KIDS scale (AOR = 0.19; p = 0.03). Otolaryngology residents and specialists' knowledge of OSA was very good. Further improving in the level of the knowledge toward OSA among the otolaryngology resident doctors should be implemented as possible by following the updated guidelines for the diagnosis and management OSA.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12070-023-04180-8.

An Overview of Systematic Reviews on the Surgical Management of Obstructive Sleep Apnoea

Background

Obstructive Sleep Apnoea (OSA) is a common sleep disorder marked by partial or total obstruction of the upper airway while a person is asleep leading to breathing difficulty, reduced oxygenation and frequent awakenings. This condition affects the general health significantly compromising quality of life. The objective of this overview  is to thoroughly assess the systematic reviews on current surgical therapies for the management of OSA in terms of patient outcomes.

Methods

A thorough literature search was performed from inception till 31st December 2022 using PubMed, and Cochrane databases. Studies evaluating the effectiveness and safety of different surgical techniques for the management of OSA were considered. The quality of articles was assessed using AMSTAR (A MeaSurement Tool to Assess systematic Reviews) and Glenny et al. checklist.

Results

Out of eighteen studies, only seven studies met the inclusion and exclusion criteria. Results showed that the majority of studies were in the pediatric age group except one systematic  review which assessed the adult age group.

Conclusion

None of the published articles had compared all surgical procedures based on the standard evaluating procedure nor followed all reporting guidelines in the primary studies. For better implementation, further multi center studies are warranted with unique reporting criteria and guidelines about pre- as well as post-operative phases. Future research should concentrate on contrasting strategies, combination therapies, and evaluating long-term effects.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12663-023-02051-x.

Comparing the Driving Skills of Adolescents with Obstructive Sleep Apnea to Healthy Controls: The Results of a Case-Controlled Observational Study

Auto crashes are a leading cause of death and injury among adolescents. Untreated obstructive sleep apnea (OSA) can cause sleepiness and inattention, which could negatively impact novice drivers, but OSA-related studies have focused on older drivers. This study used a driving simulator to examine whether licensed 16-19-year-old adolescents with OSA have diminished driving skills. Twenty-one adolescents with OSA and twenty-eight without OSA (both confirmed using polysomnography) completed two randomly ordered driving trials in a simulator (with induced distractions versus without). A mixed ANOVA examined the between-subjects effect of the OSA group, the within-subjects effect of the distraction condition, and the group-by-condition interaction effect on the ability to maintain lane position and the frequency of extended eye glances away from the roadway. T-tests were also used to examine group differences in reported sleepiness and inattention during daily life. The distraction task increased extended off-road glances and difficulties maintaining lane position (p < 0.001). However, adolescents with OSA did not display worse eye glance or lane position than controls and there were no significant group-by-condition interactions. Although the groups differed on polysomonographic features, there were also no significant differences in reported sleepiness or inattention. The distraction task negatively impacted both groups of adolescent drivers, but those with OSA did not fare differentially worse. Most adolescents in our study had mild OSA (median obstructive apnea-hypopnea index = 4.4), the most common form in the community. It remains possible that youth with more severe OSA would show increased driving impairment.

Possible cognition changes in women with polycystic ovary syndrome: a narrative review

Nowadays, polycystic ovary syndrome (PCOS) and cognitive dysfunction are major health problems among female. This narrative review aimed to investigate cognitive dysfunction in female with PCOS. English and Persian articles published in PubMed, Scopus, Web of Science, Google Scholar, PsycINFO, Scientific Information Database, and Cochrane Database of Systematic Reviews until May 2022 were searched. Sixteen studies involving 850 female with PCOS and 974 controls were assessed. In these studies, the association between biochemical factors and symptoms of PCOS and memory, attention, executive functioning, information processing speed, and visuospatial skills was evaluated. The literature review revealed the possible cognitive changes in female with PCOS. This study summarized the different aspects of cognitive function in female with PCOS due to medication, psychological problems (mood disorders caused by disease symptoms and complications), and biochemical markers, such as metabolic and sex hormone abnormalities. Considering the existing scientific gap regarding the possibility of cognitive complications in female with PCOS, further biological studies should be conducted to evaluate the potential mechanisms involved.

Differences in the effects of orthodontic treatment on airway-craniocervical functional environment in adult and adolescent patients with skeletal class II high-angle: a retrospective pilot study

INTRODUCTION

This retrospective cohort study aimed to compare the change in upper airway and craniocervical posture after orthodontic treatment between adolescent and adult patients with Class II high-angle malocclusion.

METHODS

A total of 12 adolescent (mean ± standard deviation age = 13.0 ± 2.0 years) and 12 adult patients with Class II high-angle malocclusion (mean ± standard deviation age = 23.7 ± 6.4 years) were selected in this study. The lateral cephalograms and cone beam computed tomography images of adolescent and adult patients were taken before and after treatment, which can be employed to evaluate the variables of craniofacial morphology, upper airway, and craniocervical posture through paired t tests, respectively. An independent sample t test was performed to observe the differences between two groups after orthodontic intervention. For adults and adolescents, the correlation between craniofacial morphology, upper airway, and craniocervical posture was determined through Pearson correlation analysis.

RESULTS

In all subjects, the improvements in vertical and sagittal facial morphology after treatment were observed. Anterior and inferior movements of the hyoid bone, an increase of upper airway dimension, posterior tipping of the head and a reduction of cervical inclination in the lower and middle segments post-treatment were identified in adolescence (P < 0.05). Adults displayed anterior movements of the hyoid bone, whereas no significant difference was observed in upper airway dimension and craniocervical posture (P < 0.05). Notable differences were identified in the change of hyoid position and airway volume between two groups (P > 0.05). Mandibular plane inclination, growth pattern, occlusal plane inclination, and chin position were all significantly correlated with craniocervical posture in adolescent patients. Besides, the mandibular growth pattern and chin position in adult patients were significantly correlated with craniocervical posture (P < 0.05).

CONCLUSIONS

Orthodontic treatment is capable of enhancing the facial profile of patients with skeletal class II high-angle while improving their upper airway morphology and craniocervical posture, where adolescents and adults differ substantially in that the former exhibit a more favorable alteration in the airway-craniocervical functional environment.

Solriamfetol enhances wakefulness and improves cognition and anxiety in a murine model of OSA

BACKGROUND

Obstructive sleep apnea (OSA) is a chronic condition characterized by intermittent hypoxia (IH). Excessive daytime sleepiness (EDS) is a common consequence of OSA and is associated with cognitive deficits and anxiety. Modafinil (MOD) and Solriamfetol (SOL) are potent wake-promoting agents clinically used to improve wakefulness in OSA patients with EDS.

METHODS

Male C57Bl/6J mice were exposed to either IH or room air (RA) controls during the light phase for 16 weeks. Both groups were then randomly assigned to receive once-daily intraperitoneal injections of SOL (200 mg/kg), MOD (200 mg/kg) or vehicle (VEH) for 9 days while continuing IH exposures. Sleep/wake activity was assessed during the dark (active) phase. Novel object recognition (NOR), elevated-plus maze test (EPMT), and forced swim test (FST) were performed before and after drug treatment.

RESULTS

IH exposure increased dark phase sleep percentage and reduced wake bouts lengths and induced cognitive deficits and anxiogenic effects. Both SOL and MOD treatments decreased sleep propensity under IH conditions, but only SOL promoted improvements in NOR performance (explicit memory) and reduced anxiety-like behaviors.

CONCLUSION

Chronic IH, a hallmark feature of OSA, induces EDS in young adult mice that is ameliorated by both SOL and MOD. SOL, but not MOD, significantly improves IH-induced cognitive deficits and promotes anxiolytic effects. Thus, SOL could potentially benefit OSA patients beyond EDS management.

Are We Restoring Thyroid Hormone Signaling in Levothyroxine-Treated Patients With Residual Symptoms of Hypothyroidism?

INTRODUCTION

Levothyroxine (LT4) at doses that maintain the serum thyroid-stimulating hormone levels within the normal range constitutes the standard of care for the treatment of hypothyroidism. After a few months, this eliminates the signs and symptoms of overt hypothyroidism in the majority of patients, owing to the endogenous activation of thyroxine to triiodothyronine, the biologically active thyroid hormone. Still, a small percentage of the patients (10%-20%) exhibit residual symptoms, despite having normal serum thyroid-stimulating hormone levels. These symptoms include cognitive, mood, and metabolic deficits, with a significant impairment in psychological well-being and quality of life.

OBJECTIVE

To provide a summary of progress in the approach of patients with hypothyroidism that exhibit residual symptoms despite treatment.

METHODS

We reviewed the current literature and here we focused on the mechanisms leading to a deficiency of T3 in some LT4-treated patients, the role of residual thyroid tissue and the rationale for combination therapy with LT4 + liothyronine (LT3).

RESULTS

A score of clinical trials comparing therapy with LT4 versus LT4 + LT3 concluded that both are safe and equally effective (neither is superior); however, these trials failed to recruit a sufficiently large number of patients with residual symptoms. New clinical trials that considered LT4-treated symptomatic patients revealed that such patients benefit from and prefer therapy containing LT4 + LT3; desiccated thyroid extract has also been used with similar results. A practical approach to patients with residual symptoms and on initiation of combination therapy with LT4 + LT3 is provided.

CONCLUSION

A recent joint statement of the American, British, and European Thyroid Associations recommends that a trial with combination therapy be offered to patients with hypothyroidism that do not fully benefit from therapy with LT4.

Cognitive Impairments, Neuroinflammation and Blood-Brain Barrier Permeability in Mice Exposed to Chronic Sleep Fragmentation during the Daylight Period

Obstructive sleep apnea (OSA) is a chronic condition characterized by intermittent hypoxia (IH) and sleep fragmentation (SF). In murine models, chronic SF can impair endothelial function and induce cognitive declines. These deficits are likely mediated, at least in part, by alterations in Blood-brain barrier (BBB) integrity. Male C57Bl/6J mice were randomly assigned to SF or sleep control (SC) conditions for 4 or 9 weeks and in a subset 2 or 6 weeks of normal sleep recovery. The presence of inflammation and microglia activation were evaluated. Explicit memory function was assessed with the novel object recognition (NOR) test, while BBB permeability was determined by systemic dextran-4kDA-FITC injection and Claudin 5 expression. SF exposures resulted in decreased NOR performance and in increased inflammatory markers and microglial activation, as well as enhanced BBB permeability. Explicit memory and BBB permeability were significantly associated. BBB permeability remained elevated after 2 weeks of sleep recovery (p < 0.01) and returned to baseline values only after 6 weeks. Chronic SF exposures mimicking the fragmentation of sleep that characterizes patients with OSA elicits evidence of inflammation in brain regions and explicit memory impairments in mice. Similarly, SF is also associated with increased BBB permeability, the magnitude of which is closely associated with cognitive functional losses. Despite the normalization of sleep patterns, BBB functional recovery is a protracted process that merits further investigation.

Solriamfetol improves chronic sleep fragmentation-induced increases in sleep propensity and ameliorates explicit memory in male mice

Obstructive sleep apnea (OSA) is a highly prevalent condition characterized by episodes of partial or complete breath cessation during sleep that induces sleep fragmentation (SF). One of the frequent manifestations of OSA is the presence of excessive daytime sleepiness (EDS) associated with cognitive deficits. Solriamfetol (SOL) and modafinil (MOD) are wake-promoting agents commonly prescribed to improve wakefulness in OSA patients with EDS. This study aimed to assess the effects of SOL and MOD in a murine model of OSA characterized by periodic SF. Male C57Bl/6J mice were exposed to either control sleep (SC) or SF (mimicking OSA) during the light period (06:00 h to 18:00 h) for 4 weeks, which consistently induces sustained excessive sleepiness during the dark phase. Both groups were then randomly assigned to receive once-daily intraperitoneal injections of SOL (200 mg/kg), MOD (200 mg/kg), or vehicle for 1 week while continuing exposures to SF or SC. Sleep/wake activity and sleep propensity were assessed during the dark phase. Novel Object Recognition test, Elevated-Plus Maze Test, and Forced Swim Test were performed before and after treatment. SOL or MOD decreased sleep propensity in SF, but only SOL induced improvements in explicit memory, while MOD exhibited increased anxiety behaviors. Chronic SF, a major hallmark of OSA, induces EDS in young adult mice that is mitigated by both SOL and MOD. SOL, but not MOD, significantly improves SF-induced cognitive deficits. Increased anxiety behaviors are apparent in MOD-treated mice. Further studies aiming to elucidate the beneficial cognitive effects of SOL are warranted.

Mentation Tracks Severity but not Oxygenation in Obstructive Sleep Apnea

There is a rough consensus, after decades of research, that obstructive sleep apnea (OSA) is associated with mild cognitive impairments, especially in areas of executive functioning (EF), attention/working memory (A/WM), episodic memory (EM), and speed of speed of information processing (SIP). However, there is less consensus as to whether apnea severity matters for these impairments, which sleep variables matter most to which cognitive domains, whether common OSA comorbidities contribute to these determinations, or whether the apparent associations are really artifacts of these comorbidities. In this study, 40 participants with OSA submitted to polysomnography and to neuropsychological assessment with an expanded Halstead-Reitan Test Battery. Aggregates of tests to cover the four cognitive domains mentioned above were linearly regressed on the apnea-hypopnea index (AHI), the nadir of oxygen saturation (NOS), and hypertension and diabetes mellitus (scored present or absent). The AHI predicted both EF (p = .015; sr2 = .13) and A/WM (p = .023; sr2 = 11) in the primary analyses, and EM (p = .027; sr2 = .10) in the secondary analyses. Thus, AHI may affect EF, A/WM and perhaps EM beyond NOS and beyond two of OSA's most common comorbidities. Implications of these findings are discussed here.

Adherence to Continuous Positive Airway Pressure Therapy in Pediatric Patients with Obstructive Sleep Apnea: A Meta-Analysis

Introduction

Obstructive sleep apnea (OSA) is a public health problem that affects children. Although continuous positive airway pressure (CPAP) therapy is effective, the CPAP adherence rate in children is varied. This study aimed to evaluate the CPAP adherence rate and factors associated with CPAP adherence in children with OSA using a systematic review.

Methods

The inclusion criteria were observational studies conducted in children with OSA and assessed adherence of CPAP using objective evaluation. The literature search was performed in four databases. Meta-analysis using fixed-effect model was conducted to combine results among included studies.

Results

In all, 34 studies that evaluated adherence rate and predictors of CPAP adherence in children with OSA were included, representing 21,737 patients with an average adherence rate of 46.56%. There were 11 calculations of factors predictive of CPAP adherence: age, sex, ethnicity, body mass index, obesity, income, sleep efficiency, the apnea-hypopnea index (AHI), severity of OSA, residual AHI, and lowest oxygen saturation level. Three different factors were linked to children with adherence and non-adherence to CPAP: age, body mass index, and AHI.

Conclusion

The CPAP adherence rate in children with OSA was 46.56%. Young age, low body mass index, and high AHI were associated with acceptable CPAP adherence in children with OSA.

Sedative-hypnotic effects of Boropinol-B on mice via activation of GABAA receptors

OBJECTIVES

Boropinol-B is a phenylpropanoid compound originally isolated from Boronia pinnata Sm. (Rutaceae). This study aimed to evaluate the sedative-hypnotic effects of Boropinol-B and explore the underlying mechanisms.

METHODS

Pentobarbital sodium-induced sleep mouse model and caffeine-induced insomnia mouse model were used to investigate the sedative effects of Boropinol-B. Pharmacokinetics profiles of Boropinol-B in rats were evaluated by high-performance liquid chromatography. The effects of Boropinol-B on the γ-aminobutyric acid (GABA)ergic system were investigated using ELISA assay and patch-clamp technique. Immunohistochemistry and immunofluorescence were carried out to assess the effects of Boropinol-B on sleep-related brain nucleus.

KEY FINDINGS

Boropinol-B showed significant sedative effects, including reduced sleep latency, increased sleep duration in pentobarbital sodium-treated mice and decreased locomotor activity in insomnia mice. Pharmacokinetics studies demonstrated that Boropinol-B had a rapid onset of action, a short half-life and no accumulation. It increased the GABA level in mice's brain, and promoted chloride ions influx mediated by the γ-aminobutyric acid type A (GABAA) receptors in neurons. Also, it increased the c-Fos positive ratio of GABAergic neurons in ventrolateral preoptic nucleus and decreased c-Fos expression in tuberomammillary nucleus.

CONCLUSION

Boropinol-B showed significant sedative-hypnotic effects in mice by activating the GABAA receptors and stimulating the sleep-related brain nucleus.

Aberrant Topological Properties of Brain Functional Network in Children with Obstructive Sleep Apnea Derived from Resting-State fMRI

To examine the difference in the topological properties of brain functional network between the children with obstructive sleep apnea (OSA) and healthy controls, and to explore the relationships between these properties and cognitive scores of OSA children. Twenty-four OSA children (6.5 ± 2.8 years, 15 males) and 26 healthy controls (8.0 ± 2.9 years, 11 males) underwent resting-state fMRI (rs-fMRI), based on which brain functional networks were constructed. We compared the global and regional topological properties of the network between OSA children and healthy controls. Partial correlation analysis was performed between topological properties and cognitive scores across OSA children. When comparing the OSA children with the healthy controls, lower full-scale intelligent quotient (FIQ) and verbal intelligent quotient (VIQ) were observed. Additionally, nodal degree centrality decreased in the bilateral anterior cingulate and paracingulate gyrus, but increased in the right middle frontal gyrus, the left fusiform gyrus, and the left supramarginal gyrus. Nodal efficiency decreased in the right precentral gyrus, and the bilateral anterior cingulate and paracingulate gyrus, but increased in the left fusiform gyrus. Nodal betweenness centrality increased in the dorsolateral part of the right superior frontal gyrus, the left fusiform gyrus, and the left supramarginal gyrus. Further, the nodal degree centrality in the left supramarginal gyrus was positively correlated with FIQ. In contrast, none of global topological properties showed difference between those two groups. The outcomes of OSA may impaired the regional topological properties of the brain functional network of OSA children, which may be potential neural mechanism underlying the cognitive declines of these patients.

Impact of Sleep Fragmentation on Cognition and Fatigue

Sleep continuity and efficacy are essential for optimal cognitive functions. How sleep fragmentation (SF) impairs cognitive functioning, and especially cognitive fatigue (CF), remains elusive. We investigated the impact of induced SF on CF through the TloadDback task, measuring interindividual variability in working memory capacity. Sixteen participants underwent an adaptation polysomnography night and three consecutive nights, once in a SF condition induced by non-awakening auditory stimulations, once under restorative sleep (RS) condition, counterbalanced within-subject. In both conditions, participants were administered memory, vigilance, inhibition and verbal fluency testing, and for CF the TloadDback, as well as sleep questionnaires and fatigue and sleepiness visual analog scales were administered. Subjective fatigue increased and sleep architecture was altered after SF (reduced sleep efficiency, percentage of N3 and REM, number of NREM and REM phases) despite similar total sleep time. At the behavioral level, only inhibition deteriorated after SF, and CF similarly evolved in RS and SF conditions. In line with prior research, we show that SF disrupts sleep architecture and exerts a deleterious impact on subjective fatigue and inhibition. However, young healthy participants appear able to compensate for CF induced by three consecutive SF nights. Further studies should investigate SF effects in extended and/or pathological disruption settings.

Influence of social jetlag on daytime sleepiness in obstructive sleep apnea

Social jetlag is the discrepancy between socially determined sleep timing on workdays and biologically determined sleep timing on days free of social obligation. Poor circadian timing of sleep may worsen sleep quality and increase daytime sleepiness in obstructive sleep apnea (OSA). We analysed de-identified data from 2,061 participants (75.2% male, mean [SD] age 48.6 [13.4] years) who completed Sleep Apnea Global Interdisciplinary Consortium (SAGIC) research questionnaires and underwent polysomnography at 11 international sleep clinic sites. Social jetlag was calculated as the absolute difference in the midpoints of sleep between weekdays and weekends. Daytime sleepiness was assessed using the Epworth Sleepiness Scale (ESS). Linear regression analyses were performed to estimate the association between social jetlag and daytime sleepiness, with consideration of age, sex, body mass index, ethnicity, insomnia, alcohol consumption, and habitual sleep duration as confounders. Of the participants, 61.5% had <1 h of social jetlag, 27.5% had 1 to <2 h, and 11.1% had ≥2 h. Compared to those with <1 h of social jetlag, those with ≥2 h of social jetlag had 2.07 points higher ESS (95% confidence interval [CI] 0.77-3.38, p = 0.002), and those with 1 to <2 h of social jetlag had 0.80 points higher ESS (95% CI 0.04-1.55, p = 0.04) after adjustment for potential confounding. Interaction with OSA severity was observed; social jetlag appeared to have the greatest effect on daytime sleepiness in mild OSA. As social jetlag exacerbates daytime sleepiness in OSA, improving sleep timing may be a simple but novel therapeutic target for reducing the impact of OSA.

Explicit memory, anxiety and depressive like behavior in mice exposed to chronic intermittent hypoxia, sleep fragmentation, or both during the daylight period

Obstructive sleep apnea (OSA) is a chronic and highly prevalent condition characterized by chronic intermittent hypoxia (IH) and sleep fragmentation (SF), and can lead to a vast array of end-organ morbidities, particularly affecting cardiovascular, metabolic and neurobehavioral functioning. OSA can induce cognitive and behavioral and mood deficits.

Male C57Bl/6J 8-week-old mice were housed in custom-designed cages with a silent motorized mechanical sweeper traversing the cage floor at 2-min intervals (SF) during daylight for four weeks. Sleep control (SC) consisted of keeping sweeper immobile. IH consisted of cycling FiO₂ 21% 90 seconds-6.3% 90s or room air (RA; FiO₂ 21%) for sixteen weeks and combined SF-IH was conducted for nine weeks. Open field novel object recognition (NOR) testing, elevated-plus maze test (EPMT), and forced swimming test (FST) were performed.

SF induced cognitive NOR performance impairments in mice along with reduced anxiety behaviors while IH induced deficits in NOR performance, but increased anxiety behaviors. SF-IH induced impaired performance in NOR test of similar magnitude to IH or SF alone. Combined SF-IH exposures did not affect anxiety behaviors.

Thus, both SF an IH altered cognitive function while imposing opposite effects on anxiety behaviors. SF-IH did not magnify the detrimental effects of isolated SF or IH and canceled out the effects on anxiety. Based on these findings, the underlying pathophysiologic processes underlying IH and SF adverse effects on cognitive function appear to differ, while those affecting anxiety counteract each other.

Perceived cognitive impairment in high school students in the United States

Introduction

Some youth experience cognitive difficulties that interfere with their ability to learn and function well in a school environment. We examined correlates of perceived cognitive impairment among high school students who completed a national survey conducted by the United States Centers for Disease Control and Prevention (CDC) in 2019.

Methods

Participants were high school students (grades 9–12) who completed the Youth Risk Behavior Survey (YRBS) in 2019. The CDC uses this survey to monitor risk behaviors. Students answered the following question ‘Because of a physical, mental, or emotional problem, do you have serious difficulty concentrating, remembering, or making decisions?’ as either ‘yes’ or ‘no.’ Student responses to this question were analyzed in relation to demographic variables and variables pertaining to adversity, mental health problems, and drug use.

Results

The sample included 8,349 students between the ages of 14 and 18, with 4,093 boys (49%) and 4,256 girls (51%). A large proportion reported having serious difficulty concentrating, remembering, or making decisions due to physical, mental, or emotional problems (38%). A significantly larger proportion of girls (45%) than boys (30%) reported experiencing cognitive impairment [χ²(1) = 212.23, p < 0.001; Odds Ratio = 1.95, 95% confidence interval = 1.78–2.13]. Youth who exercised regularly were significantly less likely to report cognitive impairment. Binary logistic regression was used to examine the associations between perceived cognitive impairment and adversity, mental health, and lifestyle variables separately for boys [χ²(11) = 569.158, p < 0.001; Nagelkerke R² = 0.212] and girls [χ²(11) = 1,026.189, p < 0.001; Nagelkerke R² = 0.321]. Being bullied, feeling unsafe or threatened at school, getting very low grades, insufficient sleep, and using illicit drugs were independently associated with perceived cognitive impairment in both boys and girls—after controlling for associations with depression and suicidality. Youth who denied mental health problems, psychosocial adversities, and using illicit drugs reported much lower rates of perceived cognitive impairment (boys = 13%, girls = 15%).

Conclusion

A remarkably large proportion of high school students in the United States reported experiencing serious difficulty with their cognitive functioning over the past year. Girls were significantly more likely to endorse perceived cognitive difficulties compared to boys. There was a strong association between perceived cognitive impairment and the experience of psychosocial adversity.

Obstructive sleep apnea and amyloid-β42 in adolescents: The results of a pilot study

Background. Obstructive sleep apnea (OSA) is a chronic condition characterized by repetitive collapse of the upper airway during sleep leading to intermittent hypoxia, excessive arousals and disrupt of sleep homeostasis. OSA is associated with obesity as well as pathological dynamics of cerebral beta-amyloid and dementia.The aim. Comparative assessment of the plasma beta-amyloid 42 levels in adolescents, depending on the presence or absence of OSA and obesity.Materials and methods. Seventy-four obese and non-obese male adolescents were included in the study. All participants underwent polysomnography to verify OSA and measure sleep parameters, and venipuncture for the assessment of betaamyloid 42 by enzyme-linked immunosorbent assay (ELISA).Results. After polysomnography all adolescents have been divided into four study groups: OSA obese (group 1; n = 28); non-OSA obese (group 2; n = 20); OSA non-obese (group 3; n = 11), and non-OSA non-obese (group 4 – control; n = 15). OSA obese adolescents had significant elevations in beta-amyloid 42 plasma levels compared with participants from three other groups (р = 0.007, p = 0.047 and p = 0.0002, correspondingly). Compared to both OSA non-obese adolescents and the control group, non-OSA obese patients had similar beta-amyloid 42 blood concentrations (p = 0.167 and p = 0.155, correspondingly). However, patients from the group 3 showed significantly higher beta-amyloid 42 plasma levels than controls (p = 0.004).Conclusions. Thus, OSA, accompanied by intermittent nocturnal hypoxia, and particularly OSA and obesity comorbidity, in adolescents is associated with increased beta-amyloid 42 circulating concentrations, which has a major role in pathogenesis of dementia. Beta-amyloid 42 plasma level may be recommended for use as early biomarker of cognitive impairment and neurodegenerative diseases, but future researches are needed.

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.

Assessment of the cognitive function in adult Egyptian patients with obstructive sleep apnea using the Montreal Cognitive Assessment: a retrospective large-scale study

STUDY OBJECTIVES

Sleep apnea is a chronic disorder associated with multiple recognized comorbidities. Only a few studies focus on evaluating the cognitive profile in patients diagnosed with sleep apnea. The aim of the study was to assess the cognitive functions in this population using the Montreal Cognitive Assessment.

METHODS

The study cohort was 1,445 adult patients who were referred for overnight polysomnography, 764 cases and 681 healthy controls. All participants' clinical data and comorbidities were taken, and they all performed overnight polysomnography and Montreal Cognitive Assessment.

RESULTS

A significantly higher proportion (57.5%) of sleep apnea groups were males; 15.7% were illiterate compared to the non-sleep apnea group. Hypertension and diabetes mellitus were significantly more prevalent among studied patients with sleep apnea, and the mean total score for the Montreal Cognitive Assessment scale was significantly lower among those with sleep apnea at P < .001. Those with no sleep apnea showed a significantly higher function in all attributes compared to patients with sleep apnea-namely, language, orientation, abstraction, naming, attention, and recall (P < .05).

CONCLUSIONS

Logistic regression analysis was conducted to investigate predictors for occurrence of cognitive impairment (Montreal Cognitive Assessment score < 26) among the studied sample (n = 1,445). The overall model was significant at P < .001. Variables that showed significance in univariate analysis were entered in the model. Significant predictors for cognitive impairment were being male, older age, diabetic, hypertensive, and with a lower level of education and having sleep apnea.

CITATION

Mekky JF, Yousof S, Elsayed I, Elsemelawy R, Mahmoud H, Elweshahi H. Assessment of the cognitive functions in adult Egyptian patients with obstructive sleep apnea using the Montreal Cognitive Assessment: a retrospective large-scale study. J Clin Sleep Med. 2022;18(3):721-729.

You Cannot Hit Snooze on OSA: Sequelae of Pediatric Obstructive Sleep Apnea

Pediatric obstructive sleep apnea (OSA) has been shown to not only affect the quality of sleep, but also overall health in general. Untreated or inadequately treated OSA can lead to long-term sequelae involving cardiovascular, endothelial, metabolic, endocrine, neurocognitive, and psychological consequences. The physiological effects of pediatric OSA eventually become pathological. As the complex effects of pediatric OSA are discovered, they must be identified early so that healthcare providers can be better equipped to treat and even prevent them. Ultimately, adequate management of OSA improves overall quality of life.

Intermittent hypoxia and sleep disruption in obstructive sleep apnea increase serum tau and amyloid-beta levels

Obstructive sleep apnea is characterized by intermittent hypoxia and sleep disruption, leading to accelerated neurodegenerative changes and cognitive decline. Serum amyloid-beta and tau proteins, which are markers for Alzheimer's disease, have been reported to increase in patients with obstructive sleep apnea. This study compared the serum levels of amyloid-beta proteins and tau proteins in 46 cognitively normal obstructive sleep apnea patients and 30 healthy controls. Sleep parameters and severity of obstructive sleep apnea were determined using overnight polysomnography. Serum levels of Aβ40, Aβ42, total tau and phosphorylated-tau were determined by enzyme-linked immunosorbent assay. Patients with obstructive sleep apnea had significantly higher median serum levels of Aβ40 (121.0 versus 78.3 pg ml^-1 ), Aβ42 (105.6 versus 18.6 pg ml^-1 ) and total tau (168.5 versus 10.9 pg ml^-1 ) than controls. Serum levels of phosphorylated-tau did not differ significantly between the two groups. Serum levels of amyloid and tau proteins correlated with parameters of nocturnal oxygen saturation. Rapid eye movement sleep was negatively correlated with total amyloid-beta proteins. We conclude that serum levels of amyloid-beta and total tau are higher in patients with obstructive sleep apnea and hypoxia as well as changes in sleep architecture associated with their increased levels. Patients with obstructive sleep apnea should be closely monitored for the signs of cognitive impairment. Obstructive sleep apnea is a modifiable risk factor, and its treatment may reverse neurodegenerative changes and prevent cognitive impairment.

Robot-assisted frontofacial correction in very young children with craniofacial dysostosis syndromes: a technical note and early functional outcome

OBJECTIVE

In this study, the authors aimed to 1) retrospectively analyze the early functional outcomes in a cohort of very young children with craniofacial dysostoses who underwent robot-assisted frontofacial advancement (RAFFA) or robot-assisted midface distraction (RAMD), and 2) analyze the utility of robotic assistance in improving the accuracy and safety of performing transfacial pin insertion for RAFFA or RAMD.

METHODS

A retrospective analysis of a cohort of 18 children (age range 1-42 months at presentation), who underwent RAFFA or RAMD from February 2015 to February 2021 in the craniofacial unit at Amrita Institute of Medical Sciences and Research Centre in Kochi, India, was performed. Inclusion criteria were patients who had undergone RAFFA in a single stage or RAMD where the cranial vault had been addressed earlier, had been addressed on follow-up, or had not been addressed and had follow-up of at least 6 months.

RESULTS

Overall, 18 children with syndromic craniosynostosis underwent LeFort level III midface distraction, with or without RAFFA, from February 2015 to February 2021 at a single center in India. The patients' ages ranged from 6 to 47 months at the time of the procedure. All patients had significant obstructive sleep apnea (OSA), significant ocular issues, and disturbed sleep as determined by the authors' preoperative protocol. Clinically significant intracranial pressure issues were present in 17 patients. None of the patients had injury due to the transfacial pin trajectory such as globe injury, damage to the tooth buds, or the loss of purchase during the active distraction phase. The mean distraction achieved was 23 mm (range 18-30 mm) (n = 16/18). Of the 18 patients, 10 (56%) had an excellent outcome and 6 (33%) had a satisfactory outcome. In all cases, the degree of OSA had significantly reduced after surgery. Eye closure improved in all patients, and complete closure was seen in 11 patients. On follow-up, the functional gain remained in 14 of 16 patients at the final follow-up visit. The distraction results were stable during the follow-up period (mean 36 months [range 6-72 months]).

CONCLUSIONS

The early RAFFA and RAMD protocols investigated in this study gave a significant functional advantage in very young patients with craniofacial dysostoses. The results have demonstrated the accuracy and safety of robotic assistance in performing transfacial pin insertion for RAFFA or RAMD.

Altered Spontaneous Brain Activity Related to Neurologic and Sleep Dysfunction in Children With Obstructive Sleep Apnea Syndrome

Childhood obstructive sleep apnea (OSA) is a common chronic sleep-related breathing disorder in children, which leads to growth retardation, neurocognitive impairments, and serious complications. Considering the previous studies about brain structural abnormalities in OSA, in the present study, we aimed to explore the altered spontaneous brain activity among OSA patients, using amplitude of low-frequency fluctuation (ALFF), fractional ALFF (fALFF), and regional homogeneity (ReHo) methods based on resting-state functional magnetic resonance imaging (MRI). Thirty-one untreated OSA children and 33 age-and gender-matched healthy children (HC) were included in this study. Compared with controls, the OSA group showed significant lower ALFF in the right lingual gyrus, decreased fALFF in the left middle frontal gyrus (MFG), but increased fALFF in the left precuneus. Decreased ReHo was found in the left inferior frontal gyrus (orbital part) and left middle frontal gyrus. Notably, the mean fALFF value of left MFG was not only significantly related to multiple sleep parameters but also demonstrated the best performance in ROC curve analysis. These findings revealed OSA children were associated with dysfunctions in the default mode network, the frontal lobe, and the lingual gyrus, which may implicate the underlying neurophysiological mechanisms of intrinsic brain activity. The correlation between the altered spontaneous neuronal activity and the clinical index provides early useful diagnostic biomarkers for OSA children as well.

Cognitive performance in idiopathic intracranial hypertension and relevance of intracranial pressure

Cognitive impairments have been reported in idiopathic intracranial hypertension; however, evidence supporting these deficits is scarce and contributing factors have not been defined. Using a case-control prospective study, we identified multiple domains of deficiency in a cohort of 66 female adult idiopathic intracranial hypertension patients. We identified significantly impaired attention networks (executive function) and sustained attention compared to a body mass index and age matched control group of 25 healthy female participants. We aimed to investigate how cognitive function changed over time and demonstrated that deficits were not permanent. Participants exhibited improvement in several domains including executive function, sustained attention and verbal short-term memory over 12-month follow-up. Improved cognition over time was associated with reduction in intracranial pressure but not body weight. We then evaluated cognition before and after a lumbar puncture with acute reduction in intracranial pressure and noted significant improvement in sustained attention to response task performance. The impact of comorbidities (headache, depression, adiposity and obstructive sleep apnoea) was also explored. We observed that body mass index and the obesity associated cytokine interleukin-6 (serum and cerebrospinal fluid) were not associated with cognitive performance. Headache severity during cognitive testing, co-morbid depression and markers of obstructive sleep apnoea were adversely associated with cognitive performance. Dysregulation of the cortisol generating enzyme 11β hydroxysteroid dehydrogenase type 1 has been observed in idiopathic intracranial hypertension. Elevated cortisol has been associated with impaired cognition. Here, we utilized liquid chromatography-tandem mass spectrometry for multi-steroid profiling in serum and cerebrospinal fluid in idiopathic intracranial hypertension patients. We noted that reduction in the serum cortisol:cortisone ratio in those undergoing bariatric surgery at 12 months was associated with improving verbal working memory. The clinical relevance of cognitive deficits was noted in their significant association with impaired reliability to perform visual field tests, the cornerstone of monitoring vision in idiopathic intracranial hypertension. Our findings propose that cognitive impairment should be accepted as a clinical manifestation of idiopathic intracranial hypertension and impairs the ability to perform visual field testing reliably. Importantly, cognitive deficits can improve over time and with reduction of intracranial pressure. Treating comorbid depression, obstructive sleep apnoea and headache could improve cognitive performance in idiopathic intracranial hypertension.

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.

Cognitive performance is lower among individuals with overlap syndrome than in individuals with COPD or obstructive sleep apnea alone: association with carotid artery stiffness

Chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea (OSA) are both independently associated with increased cardiovascular disease (CVD) risk and impaired cognitive function. It is unknown if individuals with both COPD and OSA (i.e., overlap syndrome) have greater common carotid artery (CCA) stiffness, an independent predictor of CVD risk, and lower cognitive performance than either COPD or OSA alone. Elevated CCA stiffness is associated with cognitive impairment in former smokers with and without COPD in past studies. We compared CCA stiffness and cognitive performance between former smokers with overlap syndrome, COPD only, OSA only and former smoker controls using analysis of covariance (ANCOVA) tests to adjust for age, sex, body mass index (BMI), pack years, and postbronchodilator FEV1/FVC. We also examined the association between CCA stiffness and cognitive performance among each group separately. Individuals with overlap syndrome (n = 12) had greater CCA β-stiffness index (P = 0.015) and lower executive function-processing speed (P = 0.019) than individuals with COPD alone (n = 47), OSA alone (n = 9), and former smoker controls (n = 21), differences that remained significant after adjusting for age, BMI, sex, pack years, and FEV1/FVC. Higher CCA β-stiffness index was associated with lower executive function-processing speed in individuals with overlap syndrome (r = -0.58, P = 0.047). These data suggest that CCA stiffness is greater and cognitive performance is lower among individuals with overlap syndrome compared with individuals with COPD or OSA alone and that CCA stiffening may be an underlying mechanism contributing to the lower cognitive performance observed in patients with overlap syndrome.NEW & NOTEWORTHY Previous studies have demonstrated greater carotid artery stiffness and lower cognitive function among individuals with COPD alone and OSA alone. However, the present study is the first to demonstrate that individuals that have both COPD and OSA (i.e., overlap syndrome) have greater carotid artery stiffness and lower executive function-processing speed than individuals with either disorder alone. Furthermore, among individuals with overlap syndrome greater carotid artery stiffness is associated with lower executive function-processing speed.

Circadian Biology in Obstructive Sleep Apnea

Obstructive sleep apnea (OSA) is a complex process that can lead to the dysregulation of the molecular clock, as well as 24 h rhythms of sleep and wake, blood pressure, and other associated biological processes. Previous work has demonstrated crosstalk between the circadian clock and hypoxia-responsive pathways. However, even in the absence of OSA, disrupted clocks can exacerbate OSA-associated outcomes (e.g., cardiovascular or cognitive outcomes). As we expand our understanding of circadian biology in the setting of OSA, this information could play a significant role in the diagnosis and treatment of OSA. Here, we summarize the pre-existing knowledge of circadian biology in patients with OSA and examine the utility of circadian biomarkers as alternative clinical tools.

Poor sleep is associated with small hippocampal subfields in cognitively normal elderly individuals

Recent studies demonstrated reduced hippocampal volumes in elderly healthy individuals who are cognitively normal but poor sleepers. The association between sleep quality and the pattern of volume loss across hippocampal subfields (HSs) is not well known. Thus, it is the focus of the present study. Sleep quality was self-assessed using the Pittsburgh Sleep Quality Index (PSQI). The HS volumes were measured using sub-millimetre in-plane resolution T2-weighted magnetic resonance imaging data. A total of 67 cognitively normal elderly individuals aged 60-83 years were classified into 30 normal sleepers with a PSQI <5 and 37 poor sleepers with a PSQI ≥5. The two groups were equivalent in age, gender distribution, ethnicity, education attainment, handedness and cognitive performance. Compared to normal sleepers, poor sleepers exhibited significantly lower normalised volumes in the left cornu ammonis field 1 (CA1), dentate gyrus (DG) and subiculum. In contrast, there were no significant differences in normalised grey and white matter volumes between the two groups. The global PSQI was negatively associated with the normalised volumes of the left CA1, DG and subiculum. Sleep duration was associated with the normalised volumes of the bilateral CA1, DG, left CA2 and subiculum. Verbal memory scores were associated with the left CA1 volume. In conclusion, poor sleep quality, especially insufficient sleep duration, was associated with volume loss in several HSs that are involved in specific learning and memory tasks. As the hippocampus does not regulate sleep, it is more likely that poor sleep leads to small hippocampi. Thus, based on this assumption, improving sleep quality of poor sleeper elderly individuals could benefit hippocampal health.

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.

Socioeconomic disparities in obstructive sleep apnea: a systematic review of empirical research

BACKGROUND

Considering socioeconomic status (SES) in the diagnosis of obstructive sleep apnea (OSA) will enhance our understanding of socioeconomic disparities in clinical practice of sleep medicine. This systematic review analyzes the relations between SES and OSA measures.

METHODOLOGY

Eleven articles were identified through the Pubmed database. The National Institute of Health's Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies was used to rate the quality of these studies.

RESULTS

This systematic review revealed that associations between socioeconomic status and OSA measures are similar for both adults, children, and adolescents. Our findings showed that: (1) A lower SES is associated with an increased risk of OSA, both in adults and children/adolescents as well as for men and women. (2) Several studies assessed sleep outcomes with a single question, an approach that is unable to capture the multi-dimensionality and day-to-day variability of sleep in general or OSA in particular, (3) Low SES has detrimental effects on sleep health. (4) Sleep questionnaires are more commonly used than objective measure to assess OSA.

CONCLUSIONS

Interaction between SES and OSA must be better understood to improve current clinical guidelines. Living conditions influence the trajectory of OSA with unknown speed and for an, undetermined period, pointing to the need for more studies on this topic. Future work should identify the effect of SES on the development and progression of OSA, determine the effect of behavioral intervention and local public health programs to reduce social inequalities associated with OSA.

A critical analysis of the purported role of hypoxaemia in the comorbidity of obstructive sleep apnoea and epilepsy

Obstructive sleep apnoea (OSA) is a globally prevalent sleep disorder of significant health concern and confounded with several comorbidities resulting in adverse effect(s) on quality of life in patients afflicted with it. Of particular interest is the enigmatic high comorbidity of OSA with epilepsy, the exact underlying pathophysiology of which remains elusive despite a multitude of research performed in the last four decades. Hypoxaemia, which is an important characteristic feature found in OSA during apnoeic spells, has been implicated in the high comorbidity of OSA with epilepsy, the basis of which rests upon hypoxaemia-mediated brain damage, subcortical release phenomenon, oxidative stress and neuroinflammatory reactions. However, several studies present contradictory evidences that potentially refute the hypoxaemia-based mechanism. Additionally, the role of hypercapnia thatgenerally accompanies hypoxaemia during apnoeic spells, cannot be overlooked and is known to be potentially protective against neuronal hyperexcitability. Thus, hypoxaemia theory implicated in the high comorbidity of OSA and epilepsy appears weak and refutable. This brief paper studies and critically analyses the role of hypoxaemia in conjunction with hypercapnia in the underlying pathophysiology of the comorbidity.

Case Report: Parasomnia Overlap Disorder Induced by Obstructive Sleep Hypopnea Apnea Syndrome: A Case Report and Literature Review

Obstructive sleep apnea hypopnea syndrome (OSAHS) and parasomnia overlap disorder (POD) are types of sleep disorders. When the symptoms of both conditions coexist, the POD symptoms are most likely caused by OSAHS. In these cases, the symptoms of POD will be relieved when OSAHS is effectively treated. We refer to these cases as symptomatic POD (related to OSAHS), which differs in pathophysiology, complications, and treatment from idiopathic POD. It is important to note that the treatment for idiopathic POD may aggravate the symptoms of OSAHS. In this case, we used video polysomnography (v-PSG) on a POD patient with suspected OSAHS to distinguish idiopathic POD from symptomatic POD, to inform the appropriate treatment course. The video results and clinical features lead us to diagnose symptomatic POD, and we treated the patient with auto-set continuous positive airway pressure to address their OSAHS. This course of treatment resolved all POD-related symptoms. Here, we discuss this case and review the relevant literature. This report highlights the importance of the use of v-PSG in the clinical diagnosis, differential diagnosis, and subsequent treatment of POD.

Impact of Obstructive Sleep Apnea on Cognitive and Motor Functions in Parkinson's Disease

INTRODUCTION

Parkinson's disease (PD) is a chronic neurodegenerative disorder that presents with motor and non-motor manifestations. Amongst the non-motor features, various forms of sleep disturbances can occur, and obstructive sleep apnea (OSA) is considered to be a common comorbidity. We conducted this systematic review and meta-analysis to assess the impact of OSA on cognitive and motor functions in PD.

METHODS

The information sources of for this systematic review and meta-analysis were PubMed, SCOPUS, Web of Science, and ScienceDirect. Studies meeting the following criteria were included: (1) studies including idiopathic PD patients, (2) studies using polysomnography to categorize PD patients into PD with OSA and PD without OSA, and (3) studies with observational designs (case-control, cohort, or cross-sectional). Data analysis was performed using RevMan.

RESULTS

Our meta-analysis showed that OSA was associated with significantly lower scores of Montreal Cognitive Assessments (MoCA) (mean difference (MD) = -0.70, 95% confidence interval (CI) [-1.28, -0.13], P = 0.01) and Mini-Mental State Examination (MMSE) (MD = -0.69, 95% CI [-1.17, -0.21], P = 0.005). Moreover, the score of the motor part of the Unified Parkinson's Disease Rating Scale (UPDRS III) was significantly higher in PD patients with OSA as compared with those without OSA (MD = 1.63, 95% CI [0.03, 3.23], P = 0.049).

CONCLUSIONS

OSA is associated with increased severity of PD-associated cognitive dysfunction and motor symptoms. However, further studies are needed to corroborate these findings, assess the underlying mechanisms by which OSA influences the motor and cognitive functions in PD, and investigate whether OSA can accelerate the neurodegenerative process of PD. © 2020 International Parkinson and Movement Disorder Society.

Increased nocturnal arterial pulsation frequencies of obstructive sleep apnoea patients is associated with an increased number of lapses in a psychomotor vigilance task

Objectives

Besides hypoxaemia severity, heart rate variability has been linked to cognitive decline in obstructive sleep apnoea (OSA) patients. Thus, our aim was to examine whether the frequency domain features of a nocturnal photoplethysmogram (PPG) can be linked to poor performance in the psychomotor vigilance task (PVT).

Methods

PPG signals from 567 suspected OSA patients, extracted from Type 1 diagnostic polysomnography, and corresponding results of PVT were retrospectively examined. The frequency content of complete PPGs was determined, and analyses were conducted separately for men (n=327) and women (n=240). Patients were grouped into PVT performance quartiles based on the number of lapses (reaction times ≥500 ms) and within-test variation in reaction times. The best-performing (Q1) and worst-performing (Q4) quartiles were compared due the lack of clinical thresholds in PVT.

Results

We found that the increase in arterial pulsation frequency (APF) in both men and women was associated with a higher number of lapses. Higher APF was also associated with higher within-test variation in men, but not in women. Median APF (β=0.27, p=0.01), time spent under 90% saturation (β=0.05, p<0.01), female sex (β=1.29, p<0.01), older age (β=0.03, p<0.01) and subjective sleepiness (β=0.07, p<0.01) were significant predictors of belonging to Q4 based on lapses. Only female sex (β=0.75, p<0.01) and depression (β=0.91, p<0.02) were significant predictors of belonging to Q4 based on the within-test variation.

Conclusions

In conclusion, increased APF in PPG provides a possible polysomnography indicator for deteriorated vigilance especially in male OSA patients. This finding highlights the connection between cardiorespiratory regulation, vigilance and OSA. However, our results indicate substantial sex-dependent differences that warrant further prospective studies.

[Obstructive sleep apnea syndrome and cognitive impairment]

Sleep-disordered breathing is associated with sleep fragmentation and reduced blood oxygenation due to apnea and hypopnea episodes. Multiple studies indicate that obstructive sleep apnea syndrome (OSAS) can have negative impact on cognitive functioning, primarily executive functions, attention, and episodic memory. The attention is also focused on cognition in patients with neurologic and psychiatric comorbidities. There are different explanatory models, which show the mechanisms of OSAS influence on cognition. However, it is still unclear how the initial severity of the disease and clinical outcomes interrelate, and which factors play role in the compensation of cognitive dysfunction. Better understanding of these issues is crucial for the prevention of cognitive impairment and rehabilitation of cognitive functioning.

How Does Adenotonsillectomy Affect the Olfactory Threshold in Children?

Adenotonsillectomy is one of the main operations on the head and neck surgery quality in children. This study aimed to compare the olfactory threshold changes in adenotonsillectomy patients. This comparative study was done on 152 children whom candidate for adenotonsillectomy before and 3 weeks after the operation referred to the Dr. Kermanshahi Hospital, Kermanshah, Iran during 2015-2016. The olfactory threshold was determined by olfactory test using phenyl butyl alcohol in propylene glycol. The orthonasal test was done by a strip and the lowest propylene glycol detection used as olfactory threshold. The mean age was 6.81 ± 3.83 of patients were boys and 69 of them were girls. The allergic rhinitis was detected in 83.6% of the patients before the adenotonsillectomy while it was only in 16.4% after adenotonsillectomy. Also, nocturia was higher before the adenotonsillectomy 104 (68.4%) compared to post-adenotonsillectomy 48 (31.6%). In 73 (48%) patients, the sleep quality score was 10 after the surgery while there was a patient with score 10 before the operation. The positive allergic rhinitis was higher in male 70 (84.3%) compared to female 57 (82.6%). Also, no significant difference detected on nocturia (P = 0.531). Also, significant difference detected between 2 groups in sleep quality score before and after the adenotonsillectomy (P = 0.001). The olfactory threshold significantly improved after surgery compared to previous (P = 0.034). These results suggest olfactory threshold improves after adenotonsillectomy in children.

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.

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.