Role of NF-κB in cardiac changes of obstructive sleep apnoea rabbits treated by mandibular advancement device

BACKGROUND

Obstructive sleep apnoea (OSA) is an independent risk factor for cardiovascular diseases. We aimed to investigate the role of nuclear factor-kappa B (NF-κB) in the changes of cardiac structures in OSA rabbits treated by mandibular advancement device (MAD).

METHODS

Eighteen male New Zealand white rabbits aged 6 months were randomly divided into three groups: control group, group OSA and group MAD. Hyaluronate gel was injected into the soft palate of the rabbits in group OSA and group MAD to induce OSA. The cone beam computer tomography (CBCT) of the upper airway and polysomnography (PSG) was performed to ensure successful modelling. CBCT and PSG were applied again to detect the effects of MAD treatment. All animals were induced to sleep in a supine position for 4-6 h a day for 8 weeks. Then the levels of NF-κB, Interleukin 6 (IL-6), Interleukin 10 (IL-10) and the proportion of myocardial fibrosis (MF) were detected.

RESULTS

The higher activation of NF-κB, IL-6 and IL-10 were found in the OSA group than in the control group, leading to the increase of collagen fibres compared with the control group. Furthermore, the apnoea-hypopnea index (AHI) was positively correlated with the above factors. There were no significant differences between group MAD and the control group.

CONCLUSION

The NF-κB pathway was activated in the myocardium of OSA rabbits, which accelerated the development of MF. Early application of MAD could reduce the activation of NF-κB in the myocardium and prevent the development of MF.

Impacts of mandibular setback with or without maxillary advancement for class III skeletal correction on sleep-related respiratory parameters: A systematic review and meta-analysis

A systematic review and meta-analysis was conducted to evaluate the impacts of mandibular setback with or without maxillary advancement for class III skeletal correction on respiratory parameters measured by polysomnography (PSG) and to compare these respiratory parameters between these procedures for class III skeletal correction. Six electronic databases were searched up to June 2023. Studies comparing PSG parameters before and after orthognathic surgery for skeletal class III patients were selected for further analysis. The outcomes of interest were apnoea-hypopnea index (AHI), respiratory disturbance index (RDI), the lowest oxygen saturation (lowest SpO2), the average oxygen saturation (mean SpO2), and the 3% oxygen desaturation index (3% ODI). Data extraction, methodological quality assessment, risk of bias assessment, meta-analysis, and subgroup analysis were performed. Sixteen studies with a total of 476 patients who underwent orthognathic surgery for class III skeletal correction were included for meta-analysis. The risk of bias level was moderate for most studies. All PSG parameters before and after orthognathic surgery were not significantly different. The different surgical procedures also did not significantly affect post-operative PSG parameters. 5.8% of patients developed post-operative obstructive sleep apnoea (OSA). Most of them underwent a large distance of mandibular setback. There is a moderate level of evidence that mandibular setback with or without maxillary advancement for class III skeletal correction does not pre-dispose young and healthy patients to obstructive sleep apnoea when evaluated in the short term after surgery. However, post-operatively developed OSA was found in several isolated cases that underwent a large amount of mandibular setback with or without maxillary advancement.

Up-to-date data on NightLase laser treatment of snoring for discussion

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Assessment of oropharyngeal respiratory volume and sleep apnoea scores using peripheral arterial tonometry may improve diagnosis and treatment planning of combined dysgnathia therapy approaches

BACKGROUND

Increased daytime sleepiness is a frequently reported symptom in patients with pronounced dysgnathia.

OBJECTIVES

This study investigated possible correlations using home peripheral arterial tonometry (PAT) and oropharyngeal airway volume determination in patients with dysgnathia and daytime sleepiness.

METHODS

Twenty patients (13 male, median age 27.6 ± 6.8 years) with abnormal sleep history and 10 skeletal neutral configured controls (6 male, median age 29.5 ± 4.2 years) with normal sleep history were examined. Patients and controls were evaluated for apnoea-hypopnoea index (AHI), respiratory disturbance index (RDI), oxygen desaturation index (ODI), snoring volume (dB), total sleep time (TST) and REM-percentage (REM). Airway volumetry was measured via CBCT. Individual user experience for PAT was assessed using the User Experience Questionnaire (UEQ).

RESULTS

Patients had significantly higher respiratory scores than controls. AHI increased 4.6-fold (p = .006), RDI 2.5-fold (p = .008) and ODI 6.4-fold (p < .001). Oropharyngeal volumes showed a 30% decrease (p = .003). dB, TST and REM showed no significant differences. AHI (r = -.51; p = .005), ODI (r = -.60; p < .001) and RDI (r = -.45; p = .016) correlated negatively with pharyngeal volume. Wits appraisal correlated negatively with oropharyngeal volume (r = -.47; p = .010) and positively with AHI (r = .41; p = .03) and ODI (r = .49; p = .007). dB and TST (r = -.49; p = .008) and REM and RDI (r = -.43; p = .02) correlated negatively. UEQ-KPI (2.17 ± 0.24) confirmed excellent usability of PAT.

CONCLUSION

Patients with mandibular retrognathia and abnormal sleep history showed significantly higher respiratory indices and smaller oropharyngeal volumes than neutrally configured controls. The dygnathia severity directly influenced the risk of obstructive sleep apnoea.

Heart Rate Variability Analysis in Obstructive Sleep Apnoea Patients with Daytime Sleepiness

STUDY OBJECTIVES

Recent studies suggest sleepy patients with OSA are at higher risk for incident cardiovascular disease. This study assessed cardiac autonomic function in sleepy versus non-sleepy patients with obstructive sleep apnoea (OSA) using heart rate variability (HRV) analysis. We hypothesised that HRV profiles of sleepy patients would indicate higher cardiovascular risk.

METHODS

Electrocardiograms (ECG) derived from polysomnograms (PSG) collected by the Sydney Sleep Biobank were used to study HRV in groups of sleepy (ESS≥10) and non-sleepy OSA patients (ESS<10). HRV parameters were averaged across available ECG signal during N2 sleep.

RESULTS

A total of 421 patients were evaluated, with mean age of 54 (14) years, body mass index (BMI) of 33 (9) kg/m2, apnoea hypopnoea index (AHI) of 21 (28) events/h and, 66% male. The sleepy group consisted of 119 patients, and the non-sleepy group 302 patients. Sleepy patients exhibited lower HRV values for: root mean square successive difference (RMSSD, p= 0.028); total power (TP, p= 0.031); absolute low frequency (LF, p= 0.045); and high frequency (HF, p= 0.010) power compared to Non-Sleepy patients. Sleepy patients with moderate to severe OSA exhibited lower HRV values for: (RMSSD, p= 0.045; TP, p= 0.052) ; absolute LF (p= 0.051); and HF power (p= 0.025). There were no differences in other time and frequency domain HRV markers.

CONCLUSIONS

This study shows a trend towards parasympathetic withdrawal in sleepy OSA patients, particularly in moderate to severe cases, lending mechanistic support to the link between the sleepy phenotype and CVD risk in OSA.

The use of CBCT in orthodontics with special focus on upper airway analysis in patients with sleep-disordered breathing

Applications of cone-beam CT (CBCT) in orthodontics have been increasingly discussed and evaluated in science and practice over the last two decades. The present work provides a comprehensive summary of current consolidated practice guidelines, cutting-edge innovative applications, and future outlooks about potential use of CBCT in orthodontics with a special focus on upper airway analysis in patients with sleep-disordered breathing. The present scoping review reveals that clinical applications of CBCT in orthodontics are broadly supported by evidence for the diagnosis of dental anomalies, temporomandibular joint disorders, and craniofacial malformations. On the other hand, CBCT imaging for upper airway analysis-including soft tissue diagnosis and airway morphology-needs further validation in order to provide better understanding regarding which diagnostic questions it can be expected to answer. Internationally recognized guidelines for CBCT use in orthodontics are existent, and similar ones should be developed to provide clear indications about the appropriate use of CBCT for upper airway assessment, including a list of specific clinical questions justifying its prescription.

Chronic intermittent hypoxia-induced oxidative stress activates TRB3 and phosphorylated JNK to mediate insulin resistance and cell apoptosis in the pancreas

This study explores the potential mechanisms of obstructive sleep apnoea (OSA) complicates type 2 diabetes mellitus (T2DM) by which chronic intermittent hypoxia (CIH) induces insulin resistance and cell apoptosis in the pancreas through oxidative stress. Four- and eight-week CIH rat models were established, and Tempol (100 mg/kg/d), was used as an oxidative stress inhibitor. This study included five groups: 4-week CIH, 4-week CIH-Tempol, 8-week CIH, 8-week CIH-Tempol and normal control (NC) groups. Fasting blood glucose and insulin levels were measured in the serum. The expression levels of 8-hidroxy-2-deoxyguanosine (8-OHdG), tribbles homologue 3 (TRB3), c-Jun N-terminal kinase (JNK), phosphorylated JNK (p-JNK), insulin receptor substrate-1 (IRS-1), phosphorylated IRS-1 (Ser307) (p-IRS-1ser307 ), protein kinase B (AKT), phosphorylated AKT (Ser473) (p-AKTser473 ), B cell lymphoma protein-2 (Bcl-2), cleaved-caspase-3 (Cl-caspase-3), and the islet cell apoptosis were detected in the pancreas. CIH induced oxidative stress in the pancreas. Compared with that in the NC group and CIH-Tempol groups individually, the homeostasis model assessment of insulin resistance (HOMA-IR) and apoptosis of islet cells was increased in the CIH groups. CIH-induced oxidative stress increased the expression of p-IRS-1Ser307 and decreased the expression of p-AKTSer473 . The expression levels of TRB3 and p-JNK were higher in the CIH groups than in both the CIH-Tempol and NC groups. Meanwhile, the expressions of Cl-caspase-3 and Bcl-2 were upregulated and downregulated, respectively, in the CIH groups. Hence, the present study demonstrated that CIH-induced oxidative stress might not only induce insulin resistance but also islet cell apoptosis in the pancreas through TRB3 and p-JNK.

The epidemiological characteristics of sleep disordered breathing in congestive heart failure: A prospective, single centre study in Southeast Asia

BACKGROUND

The presence of sleep-disordered breathing (SDB) in congestive heart failure (CHF) is associated with poor prognosis and is underdiagnosed despite advances in CHF management. The prevalence of SDB in CHF remains understudied in South East Asia.

METHODS

A prospective, observational single-centre study was conducted where 116 consecutive patients in a specialised heart failure clinic underwent level 1, attended polysomnography (PSG).

RESULTS

The prevalence of SDB was 78% using the apnoea-hypopnea index (AHI), AHI ⩾ 5/h threshold, and 59% with the AHI ⩾ 15/h threshold. Obstructive sleep apnoea (OSA) was the predominant type of SDB and was associated with increased body mass index and neck circumference. STOP-BANG was predictive of SDB, especially in men. Central sleep apnoea (CSA) patients had worse sleep indexes and lower awake arterial carbon dioxide. SDB was also homogenously present in preserved ejection fraction (EF) CHF.

CONCLUSION

Most of the CHF patients were found to have SDB with the utility of PSG. Local CHF guidelines should include sleep testing for all patients with CHF.The study is registered on ClinicalTrials.gov (NCT05332223) as 'The Epidemiological Characteristics of SDB in Patients with Reduced or Preserved EF CHF'.

Gender differences in the upper airway, craniofacial morphological and polysomnographic parameters in patients with obstructive sleep apnoea

BACKGROUND

Obstructive sleep apnoea (OSA) is a common sleep disorder characterized by repetitive episodes of upper airway collapse during sleep associated with arousals with or without oxygen desaturation.

OBJECTIVE

This study aims to assess and analyse the morphological and neurological factors associated with obstructive sleep apnoea using polysomnography study data and two-dimensional cephalometric analysis of airway and skeletal parameters and their correlation in the patients with varying severities of obstructive sleep apnoea.

METHODS

This study included 892 patients who underwent a complete work up, including a thorough history, clinical examination, standard polysomnography study and 2D cephalometric analysis to diagnose obstructive sleep apnoea. This study divided the participants into two groups based on the AHI score from the PSG study: AHI < 15 and AHI > 15 groups. The groups were further divided into male and female groups to study the prevalence of OSA. The analysis involved 13 cephalometric parameters: Seven linear and six angular measurements. The airway parameters measured in this study were minimum posterior airway space (PAS_min), hyoid bone to the mandibular plane (H_MNP) and soft palate length (SPL). All the subjects in this study underwent a standard overnight polysomnography study at the sleep centre in Samsung Medical Center.

RESULTS

A total of 892 adult participants (M: F = 727:165, mean age: 50.6 ± 13.2 years and age range: 18-85 years). AHI >15 group was significantly older with higher BMI, NC and WC compared to the AHI < 15 groups in both male and female groups. There was statistical significance observed in N1, N3, AI, ODI, lowest saturation (%) and apnoea max length between the groups (p < .001). The arousal index (AI), especially the respiratory arousal index was considerably higher in the male group. There were significantly higher values in all the PSG parameters in the male group. In the airway parameters, hyoid bone position and soft palate length showed significant differences (p < .001), whereas the PAS did not show any differences (p = .225) between the AHI <15 and AHI >15 groups. The overall skeletal cephalometric parameters showed no significant differences between the groups, whereas the gonial angle and AB to mandibular plane angle showed significant differences in the female group (p = .028, p = .041 respectively).

CONCLUSION

The partial correlation of cephalometric parameters with AHI showed a stronger correlation between the H_MNP and AHI in both men and women. The position of the hyoid bone and the soft palate length influences the progression of OSA, especially in male patients. This study found no direct association between the minimum PAS and varying severities of OSA in men and women. We speculate that more than the craniofacial morphological factors such as the sagittal and vertical position of the maxilla and the mandible, the position of the hyoid bone might be more responsible for the severity of OSA.

Measuring immediate surgical success in children undergoing adenotonsillectomy

Adenotonsillectomy is the most common indication for sleep-disordered breathing in children. Measuring pharyngeal closing pressures in anaesthetised children allows identification of severe obstructive sleep apnoea. This technique could help quantify immediate surgical impact and risk stratify postoperative treatment in these patients.

Dental sleep medicine education among undergraduate dental students in France

INTRODUCTION

Dental sleep medicine (DSM) is an emerging discipline that studies the oral and maxillofacial causes and consequences of sleep-related problems. DSM is of upmost importance given the major medical challenge it represents. Therefore, to verify whether the future generation of dentists would be ready to face this challenge, the main objective of this study was to assess the degree of involvement of the French dental schools in teaching DSM at the undergraduate level.

MATERIALS AND METHODS

All 16 dental schools in France were asked to participate in the study by answering to an online survey concerning the DSM curriculum during the 2018-2019 academic year. The survey was addressed to the head of the dental school and/or to relevant course coordinators and contained 10 questions related to the type, content and amount of DSM teaching to undergraduate dental students.

RESULTS

Nine of the 16 (56.2%) French dental schools responded to the questionnaire. All these nine reported the inclusion of DSM in their undergraduate curriculum. The total average hours dedicated to teaching DSM was 5.6 h (SD 4.2; range 1-15 h). Seven of the 9 dental schools spent most of their DSM curriculum teaching time in the fifth year. All of them reviewed obstructive sleep apnoea and sleep-related bruxism and covered some topics related to therapies for sleep-related breathing disorders, such as the use of oral appliance.

CONCLUSION

The results of this survey showed that, although the average hourly volume is relatively high, the DSM teaching in French dental schools appeared to be non-standardised, heterogeneous and often lacunar. It is therefore essential to develop a common curriculum and implement it in all dental schools to provide undergraduate students a comprehensive and updated teaching in DSM.

Exploring the Prevalence and Characteristics of Obstructive Sleep Apnea Among Idiopathic Pulmonary Fibrosis Patients: A Systematic Review and Meta-Analysis

The aim of this meta-analysis was to scrutinize the prevalence, characteristics, and outcomes of obstructive sleep apnea (OSA) in individuals with ideopathic pulmonary fibrosis (IPF). We carried out this systematic review and meta-analysis in accordance with the guidelines outlined by the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Statement (PRISMA). Two independent researchers systematically searched major databases, including MEDLINE/PubMed, EMBASE, and the Cochrane Library, from January 1, 2000, until December 31, 2023. We included all studies involving adult patients (age >18 years) with IPF that assessed the prevalence and characteristics of OSA in IPF patients. A total of seven studies involving a pooled sample of 411 patients were included in this meta-analysis. The pooled prevalence of OSA among individuals with IPF was found to be 70% (95% CI: 59 to 82%). Individuals with OSA exhibited a significantly higher mean body mass index (BMI) compared to their counterparts. While individuals with both IPF and OSA exhibited higher scores on the Epworth Sleepiness Scale (ESS) compared to those with IPF alone, the OSA group also showed lower oxygen saturation during sleep in comparison to non-OSA patients. In summary, OSA is a prevalent coexisting condition among individuals with IPF. This presence could worsen the nighttime oxygen saturation. Consequently, there is a need for more extensive studies involving more uniform participant groups.

Follow-up of children with Down syndrome and sleep disordered breathing and the effects of treatment on actigraphically recorded sleep, quality of life, behaviour, and daytime functioning

Children with Down syndrome are at increased risk of obstructive sleep disordered breathing, which has deleterious effects on daytime functioning. We aimed to examine the effects of treatment of sleep disordered breathing on sleep quality and daytime functioning in children with Down syndrome, and hypothesised that these would be improved. Thirty-four children completed a baseline study and a follow-up 2 years later. Measures at both time points included 7 days of actigraphy and parents completed a number of questionnaires assessing sleep, behaviour, daytime functioning, and quality of life. All children had overnight polysomnography at baseline; 15 children (44%) were treated. At baseline the treated group had more severe sleep disordered breathing compared with the untreated group: obstructive apneoa-hypopnoea index 29.3 ± 38.2 events/h versus 3.3 ± 5.2 events/h (p < 0.01). Actigraphy showed no significant differences in total sleep time, sleep efficiency, sleep schedules from baseline to follow up in either group. The sleep disturbance (p < 0.01) and total problems (p < 0.05) scales on the OSA-18 and the sleep disordered breathing subscale on the Paediatric Sleep Problem Survey Instrument (p < 0.01) improved in the treated children. There were no changes in any measure in the untreated children. Treatment of sleep disordered breathing improves symptoms, sleep disturbance and quality of life in children with Down syndrome, but has no demonstrable impact on actigraphic sleep measures or daytime behaviour or function. In contrast, children who were not treated, despite having less severe disease at baseline, had increased sleep disruption and no change in quality of life.

Biological sex-related differences in the postprandial triglyceride response to intermittent hypoxaemia in young adults: a randomized crossover trial

Obstructive sleep apnoea is characterized by chronic intermittent hypoxaemia and is independently associated with an increased risk of metabolic comorbidities (e.g. type II diabetes and ischaemic heart disease). These comorbidities could be attributable to hypoxaemia-induced alterations in blood lipid profiles. However, it remains unclear whether intermittent hypoxaemia alters triglyceridaemia differently between biological sexes. Therefore, we used a randomized crossover design to examine whether 6 h of moderate intermittent hypoxaemia (15 hypoxaemic cycles/h, 85% oxyhaemoglobin saturation) alters plasma triglyceride levels differently between men and women after a high-fat meal. Relative to men, women displayed lower levels of total triglycerides, in addition to denser triglyceride-rich lipoprotein triglycerides (TRL-TG; mainly very low-density lipoprotein triglycerides and chylomicron remnant triglycerides) and buoyant TRL-TG (mainly chylomicron triglycerides) during normoxia (ambient air) and intermittent hypoxaemia (sex × time: all P ≤ 0.008). Intermittent hypoxaemia led to higher triglyceride levels (condition: all P ≤ 0.016); however, this effect was observed only in men (sex × condition: all P ≤ 0.002). Compared with normoxia, glucose levels were higher in men and lower in women during intermittent hypoxaemia (sex × condition: P < 0.001). The different postprandial responses between biological sexes occurred despite similar reductions in mean oxyhaemoglobin saturation and similar elevations in insulin levels, non-esterified fatty acid levels and mean heart rate (sex × condition: all P ≥ 0.185). These results support growing evidence showing that intermittent hypoxaemia impacts men and women differently, and they might help to explain biological sex-related discrepancies in the rate of certain comorbidities associated with intermittent hypoxaemia. KEY POINTS: Intermittent hypoxaemia is a key characteristic of obstructive sleep apnoea and alters lipid metabolism in multiple tissues, resulting in increased circulating triglyceride levels, an important risk factor for cardiometabolic diseases. Circulating triglyceride levels are regulated differently between biological sexes, with women typically displaying much lower fasting and postprandial triglyceride levels than men, partly explaining why women of all ages experience lower mortality rates from cardiometabolic diseases. In this study, healthy young men and women consumed a high-fat meal and were then exposed to 6 h of intermittent hypoxaemia or ambient air. We show that postprandial triglyceride levels are significantly lower in women compared with men and that intermittent hypoxaemia leads to higher postprandial triglyceride levels in men only. These results might help us to understand better why women living with obstructive sleep apnoea experience lower rates of cardiometabolic diseases (e.g. type II diabetes and ischaemic heart disease) than men living with obstructive sleep apnoea.

Opioid sensitivity in treated and untreated obstructive sleep apnoea: a prospective cohort study

BACKGROUND

Opioid administration to patients with obstructive sleep apnoea (OSA) is controversial because they are believed to be more sensitive to opioids. However, objective data on opioid effects in OSA are lacking. We tested the hypothesis that subjects with untreated OSA have increased sensitivity to opioids compared with subjects without OSA, or with OSA treated with continuous positive airway pressure (CPAP) or bilevel positive airway pressure (BIPAP).

METHODS

This was a single-centre, prospective cohort study in subjects without OSA (n=20), with untreated OSA (n=33), or with treated OSA (n=21). OSA diagnosis was verified using type III (in-home) polysomnography. Subjects received a stepped-dose remifentanil infusion (target effect-site concentrations of 0.5, 1, 2, 3, 4 ng ml-1). Primary outcome was miosis (pupil area fractional change), the most sensitive opioid effect. Secondary outcomes were ventilatory rate, end-expired CO2, sedation, and thermal analgesia.

RESULTS

There were no differences in miosis between untreated OSA subjects (mean=0.51, 95% confidence interval [CI] 0.41-0.61) and subjects without OSA (mean=0.49, 95% CI 0.36-0.62) (mean difference=0.02, 95% CI -0.18 to 0.22); between treated OSA subjects (mean=0.56, 95% CI 0.43-0.68) and subjects without OSA (difference=0.07, 95% CI -0.16 to 0.29); or between untreated OSA and treated OSA (difference=-0.05, 95% CI -0.25 to 0.16). There were no significant differences between subjects without OSA, untreated OSA, and treated OSA in ventilatory rate, end-expired CO2, sedation, or thermal analgesia responses to remifentanil. There was no relationship between OSA severity and magnitude of opioid effects.

CONCLUSIONS

Neither obstructive sleep apnoea nor obstructive sleep apnoea treatment affected sensitivity to the miotic, sedative, analgesic, or respiratory depressant effects of the opioid remifentanil in awake adults. These results challenge conventional notions of opioid effects in obstructive sleep apnoea.

CLINICAL TRIAL REGISTRATION

NCT02898792 (clinicaltrials.gov).

Associations of early life and childhood risk factors with obstructive sleep apnoea in middle-age

BACKGROUND AND OBJECTIVE

Early-life risk factors for obstructive sleep apnoea (OSA) are poorly described, yet this knowledge may be critical to inform preventive strategies. We conducted the first study to investigate the association between early-life risk factors and OSA in middle-aged adults.

METHODS

Data were from population-based Tasmanian Longitudinal Health Study cohort (n = 3550) followed from 1st to 6th decades of life. Potentially relevant childhood exposures were available from a parent-completed survey at age 7-years, along with previously characterized risk factor profiles. Information on the primary outcome, probable OSA (based on a STOP-Bang questionnaire cut-off ≥5), were collected when participants were 53 years old. Associations were examined using logistic regression adjusting for potential confounders. Analyses were repeated using the Berlin questionnaire.

RESULTS

Maternal asthma (OR = 1.5; 95% CI 1.1-2.0), maternal smoking (OR = 1.2; 1.05, 1.5), childhood pleurisy/pneumonia (OR = 1.3; 1.04, 1.7) and frequent bronchitis (OR = 1.2; 1.01, 1.5) were associated with probable OSA. The risk-factor profiles of 'parental smoking' and 'frequent asthma and bronchitis' were also associated with probable OSA (OR = 1.3; 1.01, 1.6 and OR = 1.3; 1.01-1.9, respectively). Similar associations were found for Berlin questionnaire-defined OSA.

CONCLUSIONS

We found novel temporal associations of maternal asthma, parental smoking and frequent lower respiratory tract infections before the age of 7 years with adult OSA. While determination of their pathophysiological and any causal pathways require further research, these may be useful to flag the risk of OSA within clinical practice and create awareness and vigilance among at-risk groups.

Self-reported oral moistening disorders in obstructive sleep apnoea: A scoping review

BACKGROUND

Obstructive sleep apnoea (OSA) is a highly prevalent problem with significant consequences. Continuous positive airway pressure (CPAP) and oral mandibular advancement device (MAD) are considered the standard treatments for OSA. Patients may experience self-reported oral moistening disorders (OMDs) (i.e. xerostomia or drooling) at the beginning, throughout and after treatment. This affects oral health, quality of life and treatment effectiveness. The exact nature of the associations between OSA and self-reported OMD is still unknown. We aimed to provide an overview of the associations between self-reported OMD on the one hand and OSA and its treatment (namely CPAP and MAD) on the other hand. In addition, we sought to determine whether OMD affects treatment adherence.

MATERIALS AND METHODS

A literature search in PubMed was performed up to 27 September 2022. Two researchers independently assessed studies for eligibility.

RESULTS

In total, 48 studies were included. Thirteen papers investigated the association between OSA and self-reported OMD. They all suggested an association between OSA and xerostomia but not between OSA and drooling. The association between CPAP and OMD was addressed in 20 articles. The majority of studies have indicated xerostomia as a CPAP side effect; however, some have observed that xerostomia diminishes with CPAP therapy. In 15 papers, the association between MAD and OMD was investigated. In most publications, both xerostomia and drooling have been described as common side effects of MADs. These side effects are often mild and transient, and they improve as patients continue to use their appliance. Most studies found that these OMDs do not cause or are not a strong predictor of non-compliance.

CONCLUSION

Xerostomia is a common side effect of CPAP and MAD, as well as a significant symptom of OSA. It may be regarded as one of the indicators of sleep apnoea. Moreover, MAD therapy can be associated with OMD. However, it seems that OMD may be mitigated by being adherent to the therapy.

Untangling the relationship between childhood risk factors and obstructive sleep apnoea in adulthood

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The Use of Telemedicine in the Management of Continuous Positive Airway Pressure for the Treatment of Obstructive Sleep Apnoea: A Randomised Controlled Trial

Introduction: Obstructive sleep apnea (OSA) is a condition whereby the airway gets partially or totally obstructed during sleep. Gold standard treatment for moderate to severe OSA is continuous positive airway pressure (CPAP). However, compliance with treatment is often poor, with low hours of usage and patients stopping treatment. Methods: A nonblinded, single-center, randomized controlled trial was conducted with patients randomized to 1 of 3 arms (arm 1, standard care; arm 2, modem; and arm 3, modem and DreamMapper™ app). Ninety patients diagnosed with OSA requiring CPAP were recruited. Data, including CPAP compliance, apnea/hypopnea index (AHI), and Epworth sleepiness score (ESS), were collected at baseline and 14 and 180 days post-CPAP initiation. Results: Of the group participants (N = 90), 68% were male and 32% female with a mean age of 52.0 ± 13.13 years, mean body-mass index of 36.4 ± 7.91 (kg/m2), mean ESS of 10.19 ± 5.75, and mean AHI of 43.5 ± 21.92 (events/hour). There was no statistically significant difference between the three arms in mean hours of CPAP usage in 24 hours at 14 days: arm 1, 6.22 ± 2.15; arm 2, 5.47 ± 2.25; and arm 3, 6.44 ± 1.54 (p = 0.256). There were also no statistically significant differences between the three arms in mean hours of CPAP usage in 24 hours at 180 days: arm 1, 6.20 ± 1.27; arm 2, 5.57 ± 1.49; and arm 3, 6.26 ± 1.29 (p = 0.479). Discussion and Conclusion: Compliance with CPAP treatment showed no significant differences between the three arms, with high compliance observed in all arms.

Frequency of Obstructive Sleep Apnea in Patients With Cystic Fibrosis and Non-cystic Fibrosis Bronchiectasis and Its Association With Clinical Findings

OBJECTIVE

This study was designed to assess obstructive sleep apnea (OSA) in adult patients with cystic fibrosis (CF) and non-CF bronchiectasis (BE) and to relate it with clinical characteristics.

METHODS

Thirty-five CF (27 years) and 35 non-CF (24 years) BE patients were included. Demographic characteristics, medications, comorbidities, BMI, dyspnea scales, pulmonary functions, sputum cultures, exacerbations, and hospitalizations were recorded. The Epworth Sleepiness Scale (ESS) questionnaire was filled and polysomnography was performed for each patient.

RESULTS

ESS scores did not show any significant difference between CF and non-CF BE patients. Thirty-seven (53%) of all patients had OSA. There was no significant difference in OSA risk between CF and non-CF BE patients (54% vs 51%, respectively). Male gender was found to be a risk factor for OSA (68% of males vs 41% of females, respectively, p:0.026). Total sleep time, sleep efficiency, sleep latency, time spent awake after falling asleep, oxygen desaturation index, apnea-hypopnea-index (AHI), AHI in the supine position, and rapid eye movement phase did not show any significant difference between CF and non-CF patients. CF patients had significantly lower mean oxygen saturation (p:0.001) and lowest oxygen saturation (p:0.0024) levels and higher heart rate (p:0.02) compared to non-CF BE patients. Multiple logistic regression analysis of all patients revealed male gender and disease duration as risk factors for OSA (p:0.023 and p:0.041 respectively).

CONCLUSION

It is remarkable that more than half of the patients in both CF and non-CF bronchiectasis groups had OSA. Male gender and disease duration were found as risk factors for OSA.

Preface to the 9th Biennial COAST Conference: Harnessing Technology and Biomedicine for Personalized Orthodontics

OBJECTIVE

The Consortium on Orthodontic Advances in Science and Technology (COAST) convened for its 9th biennial conference titled 'Harnessing Technology and Biomedicine for Personalized Orthodontics' to explore cutting-edge craniofacial research towards building the foundations for precision care in orthodontics.

SETTING AND SAMPLE POPULATION

Seventy-five faculty, scholars, private practitioners, industry, residents and students met at the UCLA Arrowhead Lodge on 6-9 November 2022 for networking, scientific presentations and facilitated discussions. Thirty-three speakers provided state-of-the-art, evidence-based scientific and perspective updates in craniofacial and orthodontic-related fields. The overall format included an Education Innovation Award Faculty Development Career Enrichment (FaCE) workshop focused on faculty career development, three lunch and learns, keynote or short talks and poster presentations.

MATERIAL AND METHODS

The 2022 COAST Conference was organized thematically to include (a) genes, cells and environment in craniofacial development and abnormalities; (b) precision modulation of tooth movement, retention and facial growth; (c) applications of artificial intelligence in craniofacial health; (d) precision approaches to Sleep Medicine, OSA and TMJ therapies; and (e) precision technologies and appliances.

RESULTS

The collective advances in orthodontics and science represented in the manuscripts of this issue fulfil our goal of laying solid foundations for personalized orthodontics. Participants elevated the need for stronger industry-academic research partnerships to leverage knowledge gained from large datasets with treatment approaches and outcomes; systematizing the potential of big data including through multi-omics and artificial intelligence approaches; refining the genotype: phenotype correlation to create biotechnology that will rescue inherited dental and craniofacial defects; evolving studies of tooth movement, sleep apnoea and TMD treatment to accurately measure dysfunction and treatment successes; and maximizing the integration of newer orthodontic devices and digital workflows.

CONCLUSIONS

Technological advances combined with those in biomedicine and machine learning are rapidly changing the delivery of health care including that in orthodontics. These advances promise to lead to enhanced customization, efficiencies and outcomes of patient care in routine orthodontic problems and in severe craniofacial problems, OSA and TMD.

Predicting obstructive sleep apnoea and perioperative respiratory adverse events in children: role of upper airway collapsibility measurements

BACKGROUND

Obstructive sleep apnoea (OSA) and perioperative respiratory adverse events are significant risks for anaesthesia in children undergoing adenotonsillectomy. Upper airway collapse is a crucial feature of OSA that contributes to respiratory adverse events. A measure of upper airway collapsibility to identify undiagnosed OSA can help guide perioperative management. We investigated the utility of pharyngeal closing pressure (PCLOSE) for predicting OSA and respiratory adverse events.

METHODS

Children scheduled for elective adenotonsillectomy underwent in-laboratory polysomnography 2-12 weeks before surgery. PCLOSE measurements were obtained while the child was anaesthetised and breathing spontaneously just before surgery. Logistic regression was used to assess the predictive performance of PCLOSE for detecting OSA and perioperative respiratory adverse events after adjusting for potential covariates.

RESULTS

In 52 children (age, mean [standard deviation] 5.7 [1.8] yr; 20 [38%] females), airway collapse during PCLOSE was observed in 42 (81%). Of these, 19 of 42 (45%) patients did not have OSA, 15 (36%) had mild OSA, and eight (19%) had moderate-to-severe OSA. All 10 children with no evidence of airway collapse during the PCLOSE measurements did not have OSA. PCLOSE predicted moderate-to-severe OSA (odds ratio [OR] 1.71; 95% confidence interval [CI]: 1.2-2.8; P=0.011). All children with moderate-to-severe OSA could be identified at a PCLOSE threshold of -4.0 cm H2O (100% sensitivity), and most with no or mild OSA were ruled out (64.7% specificity; receiver operating characteristic/area under the curve=0.857). However, there was no significant association between respiratory adverse events and PCLOSE (OR 1.0; 95% CI: 0.8-1.1; P=0.641).

CONCLUSIONS

Measurement of PCLOSE after induction of anaesthesia can reliably identify moderate or severe OSA but not perioperative respiratory adverse events in children before adenotonsillectomy.

CLINICAL TRIAL REGISTRATION

ANZCTR ACTRN 12617001503314.

Craniofacial features of adult obese obstructive sleep apnoea patients in relation to the obesity onset - A pilot study

INTRODUCTION

Obesity and craniofacial structures are aetiologies of obstructive sleep apnoea (OSA). The effect of obesity onset on the craniofacial development and growth of obese OSA subjects has been suggested, but supporting data were lacking. This study aimed to assess the craniofacial features of adult obese OSA patients in relation to their obesity onset.

MATERIALS AND METHODS

A total of 62 adult OSA patients were included in the study, consisting of 12 early-onset (i.e. before puberty), 21 late-onset (i.e. after puberty) and 29 non-obese. All participants underwent a sleep study and cephalometric radiograph. Cephalometric analysis was conducted to measure the craniofacial features among the groups.

RESULTS

The early obesity onset group (n = 12) showed a more prognathic mandible, longer lower facial height, protrusive incisors, a more caudal position of the hyoid bone and a wider lower airway. The late-onset group (n = 21) had more proclined and protrusive upper incisors, a shallower overbite, a more inferiorly positioned hyoid bone and an obtuse craniocervical angle. The overall obese group showed a combination of the findings above, plus a shorter soft palate and shorter airway length. There was no significant difference between early and late obesity onset groups. However, the early group showed a tendency for a shallower or decreased mandibular plane angle and deeper overbite.

CONCLUSIONS

The current pilot study had many limitations but holds important information as a hypothesis generator. Craniofacial features of OSA patients with different obesity onset showed discrepancies and were distinguished from non-obese controls. Adult OSA patients with an early obesity onset showed a tendency for a more hypodivergent growth pattern than those with a late obesity onset.

Carotid body contribution to the physio-pathological consequences of intermittent hypoxia: role of nitro-oxidative stress and inflammation

Obstructive sleep apnoea (OSA), characterized by chronic intermittent hypoxia (CIH), is considered to be an independent risk for hypertension. The pathological cardiorespiratory consequences of OSA have been attributed to systemic oxidative stress, inflammation and sympathetic overflow induced by CIH, but an emerging body of evidence indicates that a nitro-oxidative and pro-inflammatory milieu within the carotid body (CB) is involved in the potentiation of CB chemosensory responses to hypoxia, which contribute to enhance the sympathetic activity. Accordingly, autonomic and cardiovascular alterations induced by CIH are critically dependent on an abnormally heightened CB chemosensory input to the nucleus of tractus solitarius (NTS), where second-order neurons project onto the rostral ventrolateral medulla (RVLM), activating pre-sympathetic neurons that control pre-ganglionic sympathetic neurons. CIH produces oxidative stress and neuroinflammation in the NTS and RVLM, which may contribute to the long-term irreversibility of the CIH-induced alterations. This brief review is mainly focused on the contribution of nitro-oxidative stress and pro-inflammatory molecules on the hyperactivation of the hypoxic chemoreflex pathway including the CB and the brainstem centres, and whether the persistence of autonomic and cardiorespiratory alterations may depend on the glial-related neuroinflammation induced by the enhanced CB chemosensory afferent input.

Chronic intermittent hypoxia-induced cardiovascular and renal dysfunction: from adaptation to maladaptation

Chronic intermittent hypoxia (CIH) is the dominant pathological feature of human obstructive sleep apnoea (OSA), which is highly prevalent and associated with cardiovascular and renal diseases. CIH causes hypertension, centred on sympathetic nervous overactivity, which persists following removal of the CIH stimulus. Molecular mechanisms contributing to CIH-induced hypertension have been carefully delineated. However, there is a dearth of knowledge on the efficacy of interventions to ameliorate high blood pressure in established disease. CIH causes endothelial dysfunction, aberrant structural remodelling of vessels and accelerates atherosclerotic processes. Pro-inflammatory and pro-oxidant pathways converge on disrupted nitric oxide signalling driving vascular dysfunction. In addition, CIH has adverse effects on the myocardium, manifesting atrial fibrillation, and cardiac remodelling progressing to contractile dysfunction. Sympatho-vagal imbalance, oxidative stress, inflammation, dysregulated HIF-1α transcriptional responses and resultant pro-apoptotic ER stress, calcium dysregulation, and mitochondrial dysfunction conspire to drive myocardial injury and failure. CIH elaborates direct and indirect effects in the kidney that initially contribute to the development of hypertension and later to chronic kidney disease. CIH-induced morphological damage of the kidney is dependent on TLR4/NF-κB/NLRP3/caspase-1 inflammasome activation and associated pyroptosis. Emerging potential therapies related to the gut-kidney axis and blockade of aryl hydrocarbon receptors (AhR) are promising. Cardiorenal outcomes in response to intermittent hypoxia present along a continuum from adaptation to maladaptation and are dependent on the intensity and duration of exposure to intermittent hypoxia. This heterogeneity of OSA is relevant to therapeutic treatment options and we argue the need for better stratification of OSA phenotypes.

Association between nasal airway minimal cross-sectional areas and obstructive sleep apnoea

BACKGROUND/OBJECTIVES

Patients with obstructive sleep apnoea (OSA) frequently present with some form of upper airway anatomical impairment. Considerable research has been conducted on the role of the structures of the jaw and pharynx in the pathogenesis of OSA; however, the significance of the nose is somewhat unclear. Computed tomography is a widely used imaging modality for assessing the nasal cavity and paranasal sinuses, but only a small amount of the acquired data is used. Our aim was to ascertain whether the size of the cross-sectional areas of the nasal airway, measured from cone beam computed tomography (CBCT) images, is associated with OSA severity.

MATERIALS/METHODS

A total of 58 patients with OSA, without any major paranasal sinus inflammatory pathology, were included in this register-based study. Patients had previously undergone ambulatory polysomnography and CBCT. The cross-sectional areas of the nasal cavity were measured in CBCT coronal sections. Statistical analyses were performed to determine any correlation between the cross-sectional area measurements and apnoea-hypopnoea index (AHI) or any significant difference in cross-sectional areas between AHI severity groups.

RESULTS

No correlation was found between AHI and the smallest, total, or sum of the anterior cross-sectional areas of the nasal airway. Furthermore, there was no statistically significant difference in the cross-sectional areas between patients with the highest and lowest AHI.

CONCLUSIONS/IMPLICATIONS

The small cross-sectional area of the anterior nasal cavity in patients without any major nasal pathology does not appear to be associated with OSA severity.

Minimally invasive, single-stage, multilevel surgery for obstructive sleep apnoea: A systematic review and meta-analysis

OBJECTIVES

Minimally invasive, single-staged multilevel surgery (MISS MLS) could be an optimal treatment for selected patients with obstructive sleep apnea (OSA). We aim to systematically review the efficacy of MISS MLS for patients with OSA, as well as the clinical outcomes and possible complications in OSA patients before and after MISS MLS.

DESIGN AND SETTING

Systematic review and meta-analysis. Six databases were searched, and the PRISMA guideline was followed.

PARTICIPANTS

Patients with OSA receiving MISS MLS.

MAIN OUTCOME MEASURES

The random-effects model was adopted for the statistical synthesis. The percentage and 95% confidence interval (CI) were adopted as the effect measurements of MISS MLS for OSA. Subgroup analyses and sensitivity analyses were also performed to identify the heterogeneity among the studies.

RESULTS

There were initially 154 articles for identification. Eventually, six studies with a total of 848 OSA patients completely met the inclusion criteria and were further enrolled for analysis. The pooled analysis showed statistically significant lower AHI (apnea/hypopnea index, /hr.; mean difference: -8.931, 95% CI: -11.591 to -6.271, I2  = 87.4%), ESS (mean difference: -2.947, 95% CI: -4.465 to -1.429, I2  = 94.9%), and snoring severity with 0-10 visual analog scale after surgery (mean difference: -4.966, 95% CI: -5.804 to -4.128, I2  = 96.4%). The success rate was 46% in mild/moderate OSA; however, 18% in severe OSA. There were no major complications occurred.

CONCLUSIONS

The acceptable surgical outcomes, esp. in mild/moderate OSA, and rare complications are the major advantages of MISS MLS. The evidence of this study could aid the decision making in selecting suitable treatment programs for OSA patients.

Respiratory effort during sleep and the rate of prevalent type 2 diabetes in obstructive sleep apnoea

AIM

To determine the association between total sleep time (TST) spent in increased respiratory effort (RE) and the prevalence of type 2 diabetes in a large cohort of individuals with suspected obstructive sleep apnoea (OSA) referred for in-laboratory polysomnography (PSG).

MATERIALS AND METHODS

We conducted a retrospective cross-sectional study using the clinical data of 1128 patients. Non-invasive measurements of RE were derived from the sleep mandibular jaw movements (MJM) bio-signal. An explainable machine-learning model was built to predict prevalent type 2 diabetes from clinical data, standard PSG indices, and MJM-derived parameters (including the proportion of TST spent with increased respiratory effort [REMOV [%TST]).

RESULTS

Original data were randomly assigned to training (n = 853) and validation (n = 275) subsets. The classification model based on 18 input features including REMOV showed good performance for predicting prevalent type 2 diabetes (sensitivity = 0.81, specificity = 0.89). Post hoc interpretation using the Shapley additive explanation method found that a high value of REMOV was the most important risk factor associated with type 2 diabetes after traditional clinical variables (age, sex, body mass index), and ahead of standard PSG metrics including the apnoea-hypopnea and oxygen desaturation indices.

CONCLUSIONS

These findings show for the first time that the proportion of sleep time spent in increased RE (assessed through MJM measurements) is an important predictor of the association with type 2 diabetes in individuals with OSA.

Starting Mandibular Advancement Device Therapy in Patients with Good Protrusive Capacity: A Randomized Pilot Study

Objective

Discomfort has been related to the poor acceptance of a mandibular advancement device (MAD) in patients with obstructive sleep apnea. The present study compared severe initial side effects between a smaller and a larger degree of mandibular advancement in patients with a good protrusive capacity.

Methods

Consecutive patients with obstructive sleep apnea and a good protrusive capacity (≥8 mm) were randomized to start treatment with the mandible advanced by either 70% of maximum protrusion (Adv70%) or by 4 mm (Adv4mm) in a pilot study with a parallel design. The main outcome was tenderness or pain in the teeth or jaws using a 0-10 visual analogue scale (VAS) (from "not at all" to "very extensive") or excluded use because of side effects during the first week of treatment. Secondary outcomes included salivation problems and bite changes.

Results

Eighteen patients were randomly selected and 17 patients fulfilled the study protocol. Four patients in the Adv70% group and none in the Adv4mm group reported severe tenderness or pain (VAS ≥7) on five or more of the seven days (p=0.03). The degree of mandibular advancement measured in millimeters correlated with the number of days with severe side effects, r=0.64 (p=0.006). The secondary side effects were minor.

Conclusion

Starting MAD treatment with 70% mandibular advancement was related to more severe side effects during the first week of treatment compared with a smaller fixed millimeter value in patients with a good protrusive capacity in this pilot study.

Rethinking O2 , CO2 and breathing during wakefulness and sleep

We have examined the importance of three long-standing questions concerning chemoreceptor influences on cardiorespiratory function which are currently experiencing a resurgence of study among physiologists and clinical investigators. Firstly, while carotid chemoreceptors (CB) are required for hypoxic stimulation of breathing, use of an isolated, extracorporeally perfused CB preparation in unanaesthetized animals with maintained tonic input from the CB, reveals that extra-CB hypoxaemia also provides dose-dependent ventilatory stimulation sufficient to account for 40-50% of the total ventilatory response to steady-state hypoxaemia. Extra-CB hyperoxia also provides a dose- and time-dependent hyperventilation. Extra-CB sites of O2 -driven ventilatory stimulation identified to date include the medulla, kidney and spinal cord. Secondly, using the isolated or denervated CB preparation in awake animals and humans has demonstrated a hyperadditive effect of CB sensory input on central CO2 sensitivity, so that tonic CB activity accounts for as much as 35-40% of the normal, air-breathing eupnoeic drive to breathe. Thirdly, we argue for a key role for CO2 chemoreception and the neural drive to breathe in the pathogenesis of upper airway obstruction during sleep (OSA), based on the following evidence: (1) removal of the wakefulness drive to breathe enhances the effects of transient CO2 changes on breathing instability; (2) oscillations in respiratory motor output precipitate pharyngeal obstruction in sleeping subjects with compliant, collapsible airways; and (3) in the majority of patients in a large OSA cohort, a reduced neural drive to breathe accompanied reductions in both airflow and pharyngeal airway muscle dilator activity, precipitating airway obstruction.

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.

Anatomical Basis of Obstructive Sleep Apnoea: A Review of Randomized Controlled Trials

Repeated obstruction and closure of the upper airway, sporadic hypoxic episodes, and sympathetic activity are symptoms of obstructive sleep apnea (OSA). Obstructive sleep apnoea is due to a combination of altered upper airway structure and muscular function, a low arousal threshold and increased loop gain. Although recurrent upper airway (UA) collapse during sleep is the most frequent clinical hallmark of OSA, the exact cause of this collapse is unknown. Furthermore, while continuous positive airway pressure aids in the management of OSA, many patients find it intolerable. As a result, a better knowledge of the causes of OSA may result in more effective treatments. We did a review of randomized controlled trials that were done in this regard in the last 10 years and whose full-text version is available on the PubMed database. A total of 20 articles were finalized for review after applying our criteria. The articles have proposed different theories regarding the anatomical basis responsible for obstructive sleep apnoea. The theories proposed by different studies in the last decade include reduced genioglossus and hypoglossal nerve activity, the pharyngeal muscles' failure to keep the airway open or tighten it, tonsils and adenoid hypertrophy, an oversensitive ventilatory control system and low respiratory arousal threshold, mandibular position, pharyngeal muscles' high sympathetic drive, cephalometric alterations such as mandibular and hyoid bone position and the length of the soft palate, obesity, and neck fat and fluid re-distribution in the body, from the lower to the upper parts while reclining. Given the diverse etiological characteristics of OSA patients and to increase our knowledge of the condition, additional study into this group is required. Filling any knowledge gaps that may exist in the anatomical basis of the onset of OSA is the main objective of this review paper.

Prediction of obstructive sleep apnoea in children and adolescents with Down syndrome

BACKGROUND

Obstructive sleep apnoea (OSA) is common in children and adolescents with Down syndrome (DS). Clinical guidelines recommend that all children with DS have polysomnography (PSG) for assessment of OSA by the age of 4 years, but access is limited and testing may be burdensome for children and families.

METHODS

The purpose of this prospective cross-sectional cohort study was to identify a model to predict OSA in this group that could be tested in an external population to triage children and adolescents with DS for PSG. These models were based on a comprehensive set of potential predictive demographic, anthropometric, quality of life and sleep-related variables.

RESULTS

The results of this study show the predictive power of a model based on the sleep disordered breathing subscale of the Pediatric Sleep Survey Instrument and sleep fragmentation quantified using actigraphy in determining moderate-severe OSA in children and adolescents with DS. This model exhibits high sensitivity (82%), specificity (80%), positive predictive value (75%) and negative predictive value (86%).

CONCLUSIONS

We demonstrate the utility of a tool containing the sleep disordered breathing subscale of the Pediatric Sleep Survey Instrument and sleep fragmentation quantified using actigraphy in identifying children and adolescents with DS who have moderate/severe OSA.

Correlation between obstructive sleep apnea and ventricular function: a cross-sectional hospital-based study

BACKGROUND

Obstructive sleep apnoea (OSA) is a major cause of cardiovascular morbidity and mortality worldwide. Previous studies showed high prevalence of OSA in heart failure. We aimed to evaluate the association of OSA with cardiac dysfunction and the importance of myocardial performance index (Tei) in identifying cardiac dysfunction.

METHODS

Participants with OSA and sinus rhythm were included, while participants with arrhythmia, debilitating disease, or significant valvular heart disease were excluded. Thirty participants were enrolled, consecutively allocated in a single group, and underwent nocturnal polysomnography, electrocardiogram, and transthoracic echocardiography.

RESULTS

The prevalence of hypertension, diabetes, and smoking in the study population was 50%, 30%, and 23.3%, respectively. The mean body mass index and apnoea-hypopnoea index (AHI) of the study population was 40.11 ± 7.5 kg/m2 and22.12 ± 13.54 events/h, respectively. There were statistically significant differences between mild, moderate, and severe OSA regarding the left ventricular end diastolic diameter, left ventricular end systolic diameter, ejection fraction, and fractional shortening (p = 0.006, p = 0.002, p = 0.014 and p = 0.011),respectively. There were statistically significant regular positive correlations between the AHI and the right and left Tei (r = 0.447, p = 0.001 and r = 0.391, p = 0.003),respectively.

CONCLUSIONS

The prevalence of OSA was more in patients with comorbidities especially hypertension and diabetes. OSA was significantly associated with ventricular remodelling and cardiac dysfunction. A significant regular positive correlation was observed between the severity of OSA and worsening cardiac function as measured by Tei. Echocardiographic evaluation of the right and left ventricles and the right and left Tei could be considered as potentially valid, reproducible, and clinically applicable non-invasive methods for estimation of ventricular global function in patients with OSA.

Diagnosis of Paediatric Obstructive Sleep-Disordered Breathing beyond Polysomnography

Obstructive sleep-disordered breathing (SDB) has significant impacts on health, and therefore, a timely and accurate diagnosis is crucial for effective management and intervention. This narrative review provides an overview of the current approaches utilised in the diagnosis of SDB in children. Diagnostic methods for SDB in children involve a combination of clinical assessment, medical history evaluation, questionnaires, and objective measurements. Polysomnography (PSG) is the diagnostic gold standard. It records activity of brain and tibial and submental muscles, heart rhythm, eye movements, oximetry, oronasal airflow, abdominal and chest movements, body position. Despite its accuracy, it is a time-consuming and expensive tool. Respiratory polygraphy instead monitors cardiorespiratory function without simultaneously assessing sleep and wakefulness; it is more affordable than PSG, but few paediatric studies compare these techniques and there is optional recommendation in children. Nocturnal oximetry is a simple and accessible exam that has high predictive value only for children at high risk. The daytime nap PSG, despite the advantage of shorter duration and lower costs, is not accurate for predicting SDB. Few paediatric data support the use of home testing during sleep. Finally, laboratory biomarkers and radiological findings are potentially useful hallmarks of SDB, but further investigations are needed to standardise their use in clinical practice.

Salivary Alterations of Myeloperoxidase in Patients with Systemic Diseases: A Systematic Review

Salivary myeloperoxidase (MPO) is a key mediator of the oral immune system, acting as an enzyme that utilises H2O2 to generate molecules with high bactericidal activity. While MPO determination in plasma is quite common, the use of saliva is still rare. Our systematic review was designed to answer the question "Are salivary levels of myeloperoxidase altered in patients with systemic diseases?". Following the inclusion and exclusion criteria, we included twenty-six studies. Altered MPO levels in saliva were most commonly found in patients with cardiovascular and gastrointestinal diseases. Most studies concerned unstimulated whole saliva, and only a few of them stimulated, mainly by chewing paraffin. Enzyme-linked immunosorbent assay (ELISA) was the most common method for determination of MPO concentrations in saliva. Increased salivary MPO levels were more often observed for inflammatory diseases, except patients with inflammatory bowel diseases who were eligible for biologic therapy. In conclusion, MPO could be altered in the saliva of patients with systematic diseases, especially cardiovascular or gastrointestinal diseases. However, further investigations are recommended to validate these outcomes.

Chronic Intermittent Hypoxia-Induced Diaphragm Muscle Weakness Is NADPH Oxidase-2 Dependent

Chronic intermittent hypoxia (CIH)-induced redox alterations underlie diaphragm muscle dysfunction. We sought to establish if NADPH oxidase 2 (NOX2)-derived reactive oxygen species (ROS) underpin CIH-induced changes in diaphragm muscle, which manifest as impaired muscle performance. Adult male mice (C57BL/6J) were assigned to one of three groups: normoxic controls (sham); chronic intermittent hypoxia-exposed (CIH, 12 cycles/hour, 8 h/day for 14 days); and CIH + apocynin (NOX2 inhibitor, 2 mM) administered in the drinking water throughout exposure to CIH. In separate studies, we examined sham and CIH-exposed NOX2-null mice (B6.129S-Cybb^TM1Din/J). Apocynin co-treatment or NOX2 deletion proved efficacious in entirely preventing diaphragm muscle dysfunction following exposure to CIH. Exposure to CIH had no effect on NOX2 expression. However, NOX4 mRNA expression was increased following exposure to CIH in wild-type and NOX2 null mice. There was no evidence of overt CIH-induced oxidative stress. A NOX2-dependent increase in genes related to muscle regeneration, antioxidant capacity, and autophagy and atrophy was evident following exposure to CIH. We suggest that NOX-dependent CIH-induced diaphragm muscle weakness has the potential to affect ventilatory and non-ventilatory performance of the respiratory system. Therapeutic strategies employing NOX2 blockade may function as an adjunct therapy to improve diaphragm muscle performance and reduce disease burden in diseases characterised by exposure to CIH, such as obstructive sleep apnoea.

A study on the prevalence of RLS in OSA and the consequences of co-occurrence

Background

Restless leg syndrome (RLS) is common among patients with obstructive sleep apnoea (OSA) but the prognostic importance of this is not studied. We have called OSA and RLS coexistence as ComOSAR.

Materials and Methods

A prospective observational study was done on patients referred for polysomnography (PSG) with the aims to evaluate 1) the prevalence of RLS in OSA and comparing it with RLS in non-OSA, 2) the prevalence of insomnia, psychiatric, metabolic and cognitive disorders in ComOSAR versus OSA alone, 3) chronic obstructive airway disease (COAD) in ComOSAR versus OSA alone. OSA, RLS and insomnia were diagnosed as per respective guidelines. They were evaluated for psychiatric disorders, metabolic disorders, cognitive disorders and COAD.

Results

Of 326 patients enrolled, 249 were OSA and 77 were non-OSA. 61/249 OSA patients, i.e. 24.4% had comorbid RLS, i.e. ComOSAR. RLS in non-OSA patients was similar (22/77, i.e. 28.5%); P = 0.41. ComOSAR had a significantly higher prevalence of insomnia (26% versus 10.1%; P = 0.016), psychiatric disorders (73.7% versus 48.4%; P = 0.00026) and cognitive deficits (72.1% versus 54.7%, P = 0.016) compared to OSA alone. Metabolic disorders like metabolic syndrome, diabetes mellitus, hypertension and coronary artery disease were also observed in a significantly higher number of patients with ComOSAR versus OSA alone (57% versus 34%; P = 0.0015). COAD was also seen in a significantly higher number of patients with ComOSAR compared to OSA alone (49% versus 19% respectively; P = 0.00001).

Conclusion

It is essential to look for RLS in patients with OSA as it leads to a significantly higher prevalence of insomnia, and cognitive, metabolic and psychiatric disorders. COAD is also more common in ComOSAR compared to OSA alone.

Neck Swelling With Valsalva

We present a rare case of bilateral pharyngocoeles in a patient with symptomatic neck swelling prominently seen with the Valsalva manoeuvre. Pharyngocoeles have only been reported a handful of times in the literature. Due to their rarity, they can easily be misdiagnosed as a laryngocoele, Zenker's diverticulum, or jugular venous phlebectasia. The diagnosis in this case was confirmed on computed tomography imaging of the neck with Valsalva performed. Our patient underwent surgical excision of the symptomatic pharyngocoele on the right side while conservative management was opted for the asymptomatic left pharyngocoele. His risk factors for developing bilateral pharyngocoeles are most likely due to the use of continuous positive airway pressure (CPAP) machine at high pressures coupled with pharyngeal wall weakness. To our knowledge, this is the first case of pharyngocoeles associated with CPAP machine use. It is important to perform a thorough assessment to appropriately diagnose and treat patients with this anatomical anomaly.

Effectiveness of Continuous Positive Airway Pressure in Treating Hypertension in Obstructive Sleep Apnea: A Traditional Review

Almost one billion individuals worldwide suffer from obstructive sleep apnea (OSA). The most widely used treatment for OSA has been continuous positive airway pressure (CPAP), but its effect on blood pressure (BP) has been challenged. Our review aims to evaluate the effects of treating OSA with CPAP on BP and BP-related morbidities in adult hypertensive patients. Medical subject headings (MeSH) terminology was used to search the PubMed Central, MEDLINE, and PubMed databases for articles on the use of CPAP in OSA patients with hypertension. We selected various forms of academic writing, encompassing complete texts that were published in the English language. The study included a total of 21 papers. OSA is a serious health concern associated with a higher risk of cardiovascular disease, kidney disease, pulmonary hypertension, and aortic stiffness, which is brought on by the periodic hypoxia caused by nocturnal respiratory episodes. For individuals with moderate-to-severe OSA, CPAP therapy has been shown to have a considerable long-term benefit with a median drop of 11 mm Hg, and high adherence results in a decrease in diastolic BP. CPAP therapy directly lowers BP in OSA patients with a body mass index (BMI) of more than 30 kg/m2 and has also demonstrated improvement in early signs of atherosclerosis with lower nocturnal systolic BP levels. OSA patients with resistant hypertension also experienced lower BP after using CPAP for a year. Therefore, our findings suggest that obesity, hypersomnolence, high nocturnal BP, prolonged CPAP usage, and resistant hypertension may all have a major impact on the BP response to CPAP therapy in individuals with severe OSA.

Cognitive Functions, Depressive and Anxiety Symptoms After One Year of CPAP Treatment in Obstructive Sleep Apnea

Objective

The study worked with depressive symptoms, anxiety score and cognitive functions in obstructive sleep apnea (OSA) patients treated with CPAP.

Methods

Eighty-one subjects with OSA and without psychiatric comorbidity were treated with CPAP for one year and completed the following scales and cognitive tests: Trail Making Test, Verbal Fluency Test, d2 Test, Beck Depression Inventory-II and Beck Anxiety Inventory. MINI ruled out psychiatric disorder. At the two months check-up, subjects were re-evaluated for depressive and anxiety symptoms, and after one year of CPAP treatment, subjects repeated cognitive tests and scales. Data about therapy adherence and effectiveness were obtained from the patient's CPAP machines.

Results

The study was completed by 59 CPAP adherent patients and eight non-adherent patients. CPAP therapy effectiveness was verified in all patients by decreasing the apnea-hypopnoea index below 5 and/or 10% of baseline values. The adherent patients significantly improved depressive and anxiety symptoms. There was also an improvement in overall performance in the attention test; however, performance in many individual items did not change. The adherent patients also improved verbal fluency and in the Part B of the Trail making test. The non-adherent group significantly increased the number of mistakes made in the d2 test; other results were non-significant.

Conclusion

According to our results, OSA patients' mood, anxiety and certain cognitive domains improved during the one-year therapy with CPAP.

Trial Registration Number

NCT03866161.

Mechanisms of Atrial Fibrillation in Obstructive Sleep Apnoea

Obstructive sleep apnoea (OSA) is a strong independent risk factor for atrial fibrillation (AF). Emerging clinical data cite adverse effects of OSA on AF induction, maintenance, disease severity, and responsiveness to treatment. Prevention using continuous positive airway pressure (CPAP) is effective in some groups but is limited by its poor compliance. Thus, an improved understanding of the underlying arrhythmogenic mechanisms will facilitate the development of novel therapies and/or better selection of those currently available to complement CPAP in alleviating the burden of AF in OSA. Arrhythmogenesis in OSA is a multifactorial process characterised by a combination of acute atrial stimulation on a background of chronic electrical, structural, and autonomic remodelling. Chronic intermittent hypoxia (CIH), a key feature of OSA, is associated with long-term adaptive changes in myocyte ion channel currents, sensitising the atria to episodic bursts of autonomic reflex activity. CIH is also a potent driver of inflammatory and hypoxic stress, leading to fibrosis, connexin downregulation, and conduction slowing. Atrial stretch is brought about by negative thoracic pressure (NTP) swings during apnoea, promoting further chronic structural remodelling, as well as acutely dysregulating calcium handling and electrical function. Here, we provide an up-to-date review of these topical mechanistic insights and their roles in arrhythmia.

A Scoping Review on the Association between Night Eating Syndrome and Physical Health, Health-Related Quality of Life, Sleep and Weight Status in Adults

Night eating syndrome (NES) is characterised by recurrent episodes of night eating, evident through excessive food consumption after the evening meal or eating after awakening from sleep, often associated with significant distress and/or impairment in functioning. This scoping review was conducted according to PRISMA-ScR (Preferred Reporting Items for Systematic Reviews and Meta-Analyses for Scoping Reviews) guidelines. The search was conducted through the use of PubMed, Medline (OVID) and SCOPUS, to identify relevant articles published within the last 10 years. Search terms including "Night eating*" OR "NES" and Boolean phrases were used to refine the search. Additionally, the age of participants was restricted to 18 years and above, to ensure only adult participants were included. The abstracts of the remaining articles were used to screen for those that were relevant. From a total of 663 citations, 30 studies assessing night eating syndrome met the inclusion criteria to be included in the review. We found inconsistent associations of NES with higher body mass index (BMI), less physical activity, type 2 diabetes mellitus (T2DM) and poorer quality of sleep. These inconsistencies may have been due to the use of different measurement methods, lack of power from small sample sizes of NES in some studies and varying ages of participants, with associations being more likely to be found in higher-quality, representative populations than in university student samples. There were no associations of NES with T2DM in clinical populations and with hypertension, OSA and metabolic syndrome, but sample sizes were small. The impacts of NES on these medical conditions should be addressed in future, using well-sized and long-term studies involving representative populations of adults. In conclusion, NES likely has negative impacts on BMI, T2DM, physical activity, and sleep quality, which in turn may increase cardio-metabolic risk. However, further research is needed to elucidate the interaction between NES and its associated features.

The association between respiratory diseases and periodontitis: A systematic review and meta-analysis

AIM

To evaluate (1) whether periodontitis has an influence on the prevalence/incidence of respiratory diseases (chronic obstructive pulmonary disease [COPD], asthma, community-acquired pneumonia [CAP], obstructive sleep apnoea [OSA] and COVID-19), and (2) what is the impact of periodontal therapy on the onset or progression of respiratory diseases.

MATERIALS AND METHODS

An electronic search was performed on Pubmed, Cochrane Library and Scopus databases up to October 2021, to identify studies answering the PECOS and PICOS questions.

RESULTS

Seventy-five articles were selected. Meta-analyses identified statistically significant associations of periodontitis with COPD (nstudies  = 12, odds ratio [OR] = 1.28, 95% confidence interval [CI] [1.16; 1.42], p < .001), and OSA (ns  = 6, OR = 1.65, 95% CI [1.21; 2.25], p = .001), but not for asthma (ns  = 9, OR = 1.53, 95% CI [0.82; 2.86], p = .181). For acute conditions, two studies were found for CAP, while for COVID-19, significant associations were found for the need of assisted ventilation (ns  = 2, OR = 6.24, 95% CI [2.78; 13.99], p < .001) and COVID-related mortality (ns  = 3, OR = 2.26, 95% CI [1.36, 3.77], p = .002). Only four intervention studies were found, showing positive effects of periodontal treatment on COPD, asthma and CAP.

CONCLUSIONS

A positive association between periodontitis and COPD, OSA and COVID-19 complications has been found, while there is a lack of intervention studies.

Is it Mandatory to do a 24 hour ABPM in all Patients with Moderate to Severe Obstructive Sleep Apnoea?

Background  Obstructive sleep apnoea (OSA) has been described as a risk factor for arterial hypertension (HT). One of the proposed mechanisms linking these conditions is non dipping (ND) pattern in nocturnal blood pressure, however evidence is variable and based on specific populations with underlying conditions. Data for OSA and ND in subjects residing at high altitude are currently unavailable. Objective  Identify the prevalence and association of moderate to severe OSA with HT and ND pattern in hypertensive and non-hypertensive otherwise healthy middle-aged individuals in residing at high altitude (Bogotá:2640 mt) Methods  Adult individuals with diagnosis of moderate to severe OSA underwent 24 hour- ambulatory blood pressure monitoring (ABPM) between 2015 and 2017. Univariable and multivariable logistic regression analysis were performed to identify predictors of HT and ND pattern. Results  Ninety-three (93) individuals (male 62.4% and median age 55) were included in the final analysis. Overall, 30.1% showed a ND pattern in ABPM and 14.9% had diurnal and nocturnal hypertension. Severe OSA (higher apnea-hiponea index [AHI]) was associated with HT (p = 0.006), but not with ND patterns (p = 0.54) in multivariable regression. Smoking status and lowest oxygen saturation during respiratory events where independently associated with ND pattern (p = 0.04), whereas age (p = 0.001) was associated with HT. Conclusions  In our sample, one in three individuals with moderate to severe OSA have non dipping patterns suggesting lack of straight association between OSA and ND. Older individuals who have higher AHI are more likely to have HT, and those who smoke have a higher risk of ND. These findings add aditional information to the multiple mechanisms involved in the relationship between OSA and ND pattern, and questions the routine use of 24-hour ABPM, particullary in our region, with limited resources and healthcare acces. However, further work with more robust methodology is needed to draw conclusions.

The effectiveness of continuous positive airway pressure for treating obstructive sleep apnoea in pregnancy: A systematic review

BACKGROUND

Obstructive sleep apnoea (OSA) occurs in 15-20% of pregnant women living with obesity. As global obesity prevalence increases, OSA in pregnancy is concurrently increasing, yet remains under-diagnosed. The effects of treating OSA in pregnancy are under-investigated.

AIM

A systematic review was conducted to determine whether treating pregnant women with OSA using continuous positive airway pressure (CPAP) will improve maternal or fetal outcomes, compared with no treatment or delayed treatment.

MATERIALS AND METHODS

Original studies in English published until May 2022 were included. Searches were conducted in Medline, PubMed, Scopus, the Cochrane Library and clinicaltrials.org. Maternal and neonatal outcome data were extracted, and quality of evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach (PROSPERO registration: CRD42019127754).

RESULTS

Seven trials met inclusion criteria. Use of CPAP in pregnancy appears to be well tolerated with reasonable adherence. Use of CPAP in pregnancy may be associated with both a reduction in blood pressure and pre-eclampsia. Birthweight may be increased by maternal CPAP treatment, and preterm birth may be reduced by treatment with CPAP in pregnancy.

CONCLUSION

Treatment of OSA with CPAP in pregnancy may reduce hypertension and, preterm birth, and may increase neonatal birthweight. However, more rigorous definitive trial evidence is required to adequately assess the indication, efficacy, and applications of CPAP treatment in pregnancy.

Prevalence of childhood obstructive sleep apnoea syndrome and its role in daytime sleepiness in Syria: a large-scale school-based cross-sectional study

Obstructive sleep apnoea syndrome (OSAS) has become vastly conceded in the last decade as a possible reason for significant morbidity in childhood. This study aims to evaluate the prevalence of OSAS among school children and to assess the interrelationship between OSAS and daytime sleepiness.

Methods and materials

This cross-sectional study was conducted with 1029 children and adolescents aged 6-15 years attending elementary and secondary schools in Damascus, Syria. The questions involved 19 sleep problems items using the children sleep habits questionnaire, and 4 sleep disorder items (loud snoring, having snorts or gasps, breathing pauses, daytime sleepiness). Total sleep time (TST) was determined by sleep habits. Severe possible OSAS (p-OSAS) was addressed as having all OSA symptoms "frequently", and mild p-OSAS was defined as having any of the symptoms "sometimes". Severe and mild daytime sleepiness were rated as being very sleepy during the day "frequently", and "sometimes", respectively. Logistic regression was applied to predict risk factors of severe and mild daytime sleepiness.

Results

The prevalence of p-OSAS was 22.2%, of them 15.8% were mild, and 6.3% were severe. p-OSAS was more recognized in males 15.2% children (P<0.05). Most p-OSAS children sleep less than 6 h of TST; however; the mean TST was significantly lower at the secondary school level (P≤0.001). Predicted risk factors for severe and mild daytime sleepiness were students' grade level (P<0.05), severe and mild p-OSAS (P≤0.001), and TST less than 6 h (P≤0.001).

Conclusions

A significant number of children have p-OSAS, affecting daytime sleepiness in school age. Physicians should consider loud snoring, and breathing pauses as marked symptoms of severe daytime sleepiness. Moreover, raising parents awareness about OSAS and daytime sleepiness is essential to ensure early access to primary care.

A machine learning approach for the diagnosis of obstructive sleep apnoea using oximetry, demographic and anthropometric data

Introduction

Obstructive sleep apnoea (OSA) is a serious but underdiagnosed condition. Demand for the gold standard diagnostic polysomnogram (PSG) far exceeds its availability. More efficient diagnostic methods are needed, even in tertiary settings. Machine learning (ML) models have strengths in disease prediction and early diagnosis. We explored the use of ML with oximetry, demographic and anthropometric data to diagnose OSA.

Methods

A total of 2,996 patients were included for modelling and divided into test and training sets. Seven commonly used supervised learning algorithms were trained with the data. Sensitivity (recall), specificity, positive predictive value (PPV) (precision), negative predictive value, area under the receiver operating characteristic curve (AUC) and F1 measure were reported for each model.

Results

In the best performing four-class model (neural network model predicting no, mild, moderate or severe OSA), a prediction of moderate and/or severe disease had a combined PPV of 94%; one out of 335 patients had no OSA and 19 had mild OSA. In the best performing two-class model (logistic regression model predicting no-mild vs. moderate-severe OSA), the PPV for moderate-severe OSA was 92%; two out of 350 patients had no OSA and 26 had mild OSA.

Conclusion

Our study showed that the prediction of moderate-severe OSA in a tertiary setting with an ML approach is a viable option to facilitate early identification of OSA. Prospective studies with home-based oximeters and analysis of other oximetry variables are the next steps towards formal implementation.