bluuebunny/crossref_metadata_2025_split huggingface dataset:
O020 Twitch in the Night: Periodic Limb Movements during Sleep in Children with Neuromuscular Disease or Cerebral Palsy
Authors: Nisbet L , Nixon G , Davey M 
Published: October 2023

Abstract

Introduction
Poor sleep is frequently reported in children with neuromuscular diseases (NMD) or cerebral palsy (CP) however ventilation is often the clinical focus. Periodic limb movements (PLMs) are frequently underdiagnosed in the paediatric population (prevalence of 5-8% in clinic-referred studies) and occur in up to 33% of children with Down syndrome. We assessed the prevalence of PLMs in children with NMD or CP.

Methods
Retrospective review of the first polysomnogram with leg electromyography in children with NMD (including Duchenne muscular dystrophy, myotonic dystrophy, and spinal muscular atrophy) or CP between 2005-2022.

Results
Leg electromyography was available in 238 children (124 NMD, 114 CP) with consent. 72 (30%) were female with a median age 9y (range 1-18y), BMI z-score 0.4 (-3.5 to 2.7), RDI 3.5/h (0-100/h) and arousal index of 11.7/h (1.3-65.6/h). Median PLM index was 0 (range 0-33/h) with %PLM arousals 0 (0-74%). The prevalence of elevated PLMs (&gt;5/h) was 9.7% and 10.5% in the NMD and CP groups respectively, with median PLM arousals of 8.5% and 4.5% respectively. There were no differences in age or sex between those with or without elevated PLMs (p&gt;0.05).

Discussion
Elevated PLM index occurred at a higher prevalence in children with NMD and CP than reported in the general paediatric population, though at lower rates than in Down syndrome. It is important that PLMs are not overlooked as identification and treatment may help improve sleep outcomes in this population. Further research is required to understand the pathophysiology of PLMs specifically in this population.
O033 Is Sleeping and Waking Important for the Cortisol Awakening Response?
Authors: Grosser L , Yates C , Dorrian J , Matthews R , Banks S 
Published: October 2023

Abstract

Introduction
The rapid rise in cortisol after waking is known as the cortisol awakening response (CAR). However, as part of its normal circadian rhythm cortisol also rises in the morning independent of awakening. If CAR is a direct response to awakening, it should be eliminated in conditions of sleep deprivation (SD). Given that an atypical CAR is associated with several psychiatric and medical disorders, understanding the factors that influence CAR is of clinical relevance. This study explored cortisol during the normal waking period prior, during, and post-SD.

Methods
N=21 (11F 22.80±4.40y) completed 62h of SD in the laboratory. Salivary cortisol was collected across 5-time-points (07:00h, 07:15h, 07:30h, and 07:45h) on 2-pre-at-home-study days, 4-in-lab-study days, and 2-post-at-home-study days. Mixed-effects ANOVAs tested for fixed effects of day, time, and their interactions on cortisol, and cortisol area under the curve (AUCi, AUCg).

Results
SD produced significant effects of time*day (p&lt;0.001). Cortisol levels at +30 and +45min post-awakening were lower on SD days. Cortisol levels on awakening (0mins) did not differ between any study days. There were significant effects of day (p&lt;0.001). AUCi and AUCg were greater on in-laboratory-baseline and recovery days compared to other study days.

Discussion
This study found CAR is not present during periods of SD when there is no ‘waking’ from sleep. It showed for the first time that CAR recovers to baseline levels following recovery sleep. While the role of the CAR remains unclear this study identified factors that future research should consider to advance understanding of its purpose.
O051 Comparison of standard CPAP therapy and the RACer airway device for the treatment of obstructive sleep apnoea: A randomised clinical trial
Authors: Neill A , Campbell A , Miller J 
Published: October 2023

Abstract

The nasal cycle is a normal ultradian physiological phenomenon where each nasal airway alternates conducting dominance. The nasal cycle occurs in obstructive sleep apnoea (OSA). Rest-Activity-Cycler positive airway pressure (RACer-PAP) is a novel treatment aiming to maintain the innate nasal cycle.

Methods
PAP naïve OSA patients were randomly assigned in a crossover design to 4 weeks RACer or control humidified CPAP (3 day wash-out). Treatment pressure determined by in-lab Auto-titration. Adherence, Epworth Sleepiness Score (ESS), quality of life (SF 36), nasal symptoms, side effects, sleep quality compared by SAS 9.4 or Likert scale.

Results
40 subjects (of 44 recruited) (29 M, 11 F) with a mean BMI 37.7kg/m2 aged 45 yrs (range 22-70 yrs) with severe OSA (mean AHI 56.4/ hr), ESS 13.6 (range 3-21) completed the study. Ethnicity included Maori (17 %), NZ European (67%), and Pacific (12.5%). The prescribed mean pressure 12.2 (range 8-18 cmH20). Adherence was greater in the humidified CPAP control than RACer- PAP arm (4:57h/night verse 4:14h/night p &lt; 0.01). Both devices similarly improved subjective sleepiness, quality of life and adverse upper airway symptoms. Humidified CPAP improved to a greater extent nasal symptom scores (baseline – final: control CPAP 2.8 vs. RACer 2.3, p = 0.03), sleep quality and was preferred (55% vrs 22 %).

Conclusion
RACer PAP improved OSA symptoms and quality of life but adherence was lower and nasal symptoms more common. This could be explained by not using humidification, technical issues with prototype machine or the use of set nasal cycle length.
O052 Patient Preference and Acceptability of Sleep Diagnostic Tests during early Pregnancy
Authors: Clements F , Chung Y , Marshall N , Melehan K , Hennessy A , Makris A , Vedam H 
Published: October 2023

Abstract

Introduction
A range of test options are available to diagnose OSA. Test acceptability is measured via successful completion, though this fails to capture the patient preference. There is a paucity of data on acceptability particularly in pregnancy. We thus developed questionnaires to assess test preference and acceptability of Apnealink-Air, Somte and Grael tests, in pregnancy till 24 weeks gestation.

Methods
Eighty-four pregnant women by 24 weeks gestation were invited to complete home Apnealink-Air, unattended-self-applied-Somte-PSG and attended-Grael-PSG. Questionnaires were beta-tested by hospital staff (unaffiliated with study). Using a 5-point Likert scale, questionnaires assessed ease of use, convenience and acceptability of repeating test. A ranking scale was used to determine test preference. Following completion of tests, participants completed questionnaires.

Results
Of 59 participants that completed any test, 35 completed any questionnaire (Apnealink(n=33), Somte(n=33), Grael(n=30), preferred test (n=29)). Ranking of test preference demonstrated Apnealink ranked 1st/72.4%, Grael 2nd/20.7% and Somte 3rd/6.9%. Apnealink, Somte and Grael questionnaire data responses were assessed for ease of use (very easy (51.6%), easy / neutral (34.4/34.4%) and very easy (33.3%) respectively), convenience (very convenient (51.6%)), neutral (36.7%) and convenient (50%) respectively), and acceptability to repeat test (very acceptable (41.9%), neutral (43.3%) and neutral(43.3%)), respectively.

Discussion
Pregnant women being assessed for OSA by 24 weeks gestation preferred Apnealink to Somte and Grael PSG. Participants reported Apnealink easiest to use, most convenient and most acceptable to repeat in a future pregnancy. Patient autonomy is an important principle; womens’ preferences should be taken into consideration in clinical sleep services and research.
O054 What Measure of CPAP Treatment is most closely Associated with Reduced Risk of Future Major Cardiovascular Events (MACE)?
Authors: Reynor A , Singh B , Maddison K , Eastwood P , Shenoy B , Walsh J , Harvey C , Dhaliwal S , McArdle N 
Published: October 2023

Abstract

Introduction
Obstructive sleep apnoea (OSA) is associated with future Major Adverse Cardiovascular Events (MACE). Continuous positive airway pressure (CPAP) is the standard treatment for OSA, but it is not known which measure of CPAP treatment is most closely associated with reduction in future MACE. We compared associations between a novel and a commonly used measure of CPAP treatment and future MACE.

Materials and Methods
Participants: 2717 adults with moderate-severe OSA attending a tertiary sleep clinic 2006-2010 completed baseline assessments and followed-up for 7years.
CPAP treatment: Month-long CPAP trial and periodic review post-trial.

Outcomes
Time to cardiac death or non-fatal hospitalisations due to MACE, or end of follow-up, using Cox proportional hazards models.

Predictors
Average nightly CPAP use and the SARAH index (Sleep-Adjusted Residual AHI), using all available device downloads
SARAH index=([AHITreatment×HoursTreatment]+[AHIUntreated×HoursUntreated])/HoursTotalSleepTime

Covariates
Demographics/comorbidities associated with MACE.

Results
MACE occurred in 18% participants.
Average nightly use: Compared to zero use, each tertile of increasing use predicted reduction in risk of MACE (tertile-0:ref, tertile-I:HR 0.632, 95%CI 0.484-0.824, p&lt;0.001, tertile-II:HR 0.772, 95%CI 0.602-0.990, p=0.042, tertile-III:HR 0.708, 95%CI 0.553-0.905, p=0.006).

SARAH
A dose-response decreasing risk of MACE with decreasing SARAH index tertiles (tertile-I:ref, tertile-II:HR 0.827, 95%CI 0.658-1.039, p= 0.102, tertile-III:HR 0.772, 95%CI 0.614-0.969, p=0.026).

Conclusions
Average nightly CPAP use and SARAH index were associated with a decreased risk of future MACE. The SARAH index showed a dose-response relationship with MACE; suggesting that it may be a better estimate of residual OSA-related cardiovascular stress.
O060 Loop gain as a measure of respiratory instability in premature infants
Authors: Mann D , Mammel D , Kemp J , Carroll J , Terrill P , Edwards B 
Published: October 2023

Abstract

Introduction
Respiratory control is often unstable in premature infants, with periodic breathing, and intermittent hypo- and hyper-oxemia. Understanding how respiratory control changes after premature birth may lead to fewer and less severe events. The aim of this study was to quantify respiratory pattern instability in preterm infants during their first weeks of life.

Methods
As part of a larger study (PreVent, NHLBI U01 HL133708 & HL133700. Dennery et al., Pediatr Res 2019:85(6),769), 55 infants (born 24w1d-28w6d weeks post-menstrual age, PMA) were studied at one or more timepoints (28, 32, 36, 40 and 52 weeks PMA). Respiratory effort (thorax and abdomen bands) and SpO2% were recorded. Airflow was derived from effort bands. Respiratory instability was quantified by a previously described loop gain (LG) model fit to visually identified artefact-free spontaneous sigh breaths during quiet sleep (Edwards et al., SLEEP, 2018:41(11)).

Results
In N=1042 sighs, LG varied considerably within and between individuals across the timepoints studied. However, mixed effects modelling revealed a significant trend for increasing LG at each timepoint (R2=.2, p&lt;0.0001, PMA fixed effect, random intercept per infant).

Discussion
On average, loop gain increased across the first ~12 weeks of life in very preterm infants. This pattern is dissimilar to that among term infants, where LG peaks between 2 and 4 postnatal weeks. In very preterm infants, understanding the PMA-specific ventilatory control instability and its typical developmental trajectory will better elucidate the challenges in maintaining SpO2% within target range through better description of expected need for respiratory support.
O064 Screen Time, Sleep, and Behavioural Development in Preschool Children: Relationships Caregiver Rules and Perceptions of Screen Time
Authors: Axelsson E , Metse A , Nanthakumar S , Robson A , Paeach G , Asis A , Purcell K 
Published: October 2023

Abstract
Sleep is highly important for children’s behaviour (Touchette et al., 2007). However, screen time is associated with poorer sleep (Janssen et al., 2020), and greater behavioural difficulties (Hinkley et al., 2018), but they are rarely investigated together. Caregivers’ rules and perceptions about screen time are also associated with children’s engagement with screens. Caregivers of preschoolers completed online questionnaires about children’s screen time, sleep-related behaviours (Child Sleep-Wake Scale), behaviour (Child Behavior Checklist (CBCL, 1.5-5)), person-social development (Ages and Stages Questionnaire-3 (ASQ-3)), and questions about their rules and perceptions of screen time. Greater screen times predicted lower personal-social scores, and better sleep-related behaviours predicted lower internalising scores. Greater screen times were predicted by caregivers’ tendency to disagree about limits on screen time and a greater inclination to think limits cause conflict. Lower child personal-social scores predicted caregivers’ tendency to disagree about screen time limits. Greater child externalising behaviours predicted caregivers’ belief that screen time helps calm their child and that time limits cause conflicts. Poorer child sleep also predicted caregivers’ tendency to think screen time limits cause conflict. Therefore, caregivers’ rules and perceptions are associated with children’s screen times, but also children’s behaviours are associated with caregivers’ rules and perceptions about screen time. This is concerning as screen time predicted poorer personal-social behaviours in children. Providing caregivers with alternative ways to manage behaviours and conflicts surrounding time limits could also help in managing children’s screen times. This could have long-term implications for healthy sleep, social, and behavioural development in children.
O078 A Comparison of Subjective Sleepiness and Subjective driving Performance between People Vulnerable Versus Resistant to Driving Impairment following Extended Wakefulness.
Authors: Nguyen K , Dunbar C , Guyett A , Bickley K , Nguyen P , Scott H , Reynolds A , Hughes M , Adams R , Lack L , Catcheside P , Cori J , Howard M , Anderson C , Stevens D , Lovato N , Vakulin A 
Published: October 2023

Abstract

Introduction
Subjective sleepiness and driving performance are generally associated but show inter-individual variability. Specifically, some people are more vulnerable, while others are more resistant to driving impairment during extended wakefulness. We examined the relationship between subjective sleepiness and driving performance in groups resistant versus vulnerable to driving impairment during extended wakefulness.

Methods
Thirty-two adults (female=18, mean age=33.0yrs, SD=14.6) completed five 60-minute driving simulator assessments across 29 hours of extended wakefulness. Perceived sleepiness (Karolinska sleepiness scale, KSS) and driving performance (nine-point Likert scale) were assessed at 10-minute intervals while driving. Through cluster analysis, participants were categorised as vulnerable (n=16) or resistant (n=16) using steering deviation and crash data. Correlations, stepwise regressions, and ROC curves were used to identify predictors of driving impairment.

Results
Perceived sleepiness and driving impairment increased across the drives during wakefulness and within drives, regardless of grouping (p&lt;0.001). The exception was the drive at 25-hours into wakefulness, where the vulnerable group showed higher perceived driving impairment within the drive (p=0.001). Pre-drive KSS, total sleep time, age and gender were not significant predictors of crashes at drives undertaken at 1-hour, 7-hours, 13-hours, or 25-hours, but were significant at 19-hours into wakefulness, together explaining 44% of the variance in crashes.

Discussion
Self-reports are sensitive to driving impairment but not differential vulnerability to performance decrements during extended wakefulness. However, the findings support that both groups can perceive their sleepiness and ideally employ appropriate countermeasures (e.g., stop driving, nap, caffeine). Future studies should target more objective predictors of vulnerable versus resistant groups.
P003 Home-based sleep study paediatric model of care
Authors: Toriola E 
Published: October 2023

Abstract

Introduction
An innovative service that was developed within a tertiary paediatric centre, involved the use of a home-based sleep study model of care (MOC) between March 2022 to September 2022. This MOC allowed low risk children to be able to undergo a sleep study earlier than, when compared to the traditional in-house sleep studies conducted within the hospital setting.

Methods
The MOC involved a sleep technician travelling to the patients’ home and then attaching sensors onto the child’s body. The at home sleep system used is a full, portable polysomnography system that gently simplifies the task of performing a sleep study while delivery secure and precise measurements from the comfort of the patient’s home. The system provides data collection via the use of electrocardiogram (ECG), electroencephalography (EEG), oximeter, plethsmography belts and facial electroculargraphs which are attached comfortably onto the patient’s body.
An outpatient’s service run by Clinical Nurse Consultants then provided 24 hour support to families for troubleshooting overnight.

Results
A total of 49 home based sleep studies were performed during this period. Almost 90% of children tested had an abnormal sleep study result and 1 in 3 had moderate to severe findings. Eight studies (19%) were below the expected quality. This is comparable to in-hospital poor quality sleep study rates.

Discussion
The MOC reduced hospital admission for a diagnostic sleep study, provided quicker assessment and in the comfort of the child’s home.
P017 The Sleep and Sleep Environment of Shift Workers in Extractive Industries: Methodology to Assess the On-Site and At-Home Sleep Environment
Authors: Beranek P 
Published: October 2023

Abstract
Shift work in extractive industries, such as mining, oil and gas, harvesting, and quarrying industries, often involves long working hours, shifts scheduled opposite the biological rhythm, and a variety of roster designs. Initial studies indicate that shift workers in extractive industries experience poor sleep, including short sleep duration and poor sleep quality. Sleep loss may result in fatigue, increasing the risk of accidents and productivity loss. The sleep environment may be a crucial factor impacting sleep, therefore, warranting investigation and potential optimisation.
This study aims to 1) characterise the sleep environment of shift workers in extractive industries, and 2) determine sleep environment factors that negatively affect the sleep of shift workers in extractive industries. This study consists of a self-report and an objective assessment of sleep environment and sleep, utilising a large sample and a subsample, respectively. This study applies survey instruments, wearables, and data loggers to obtain data on sleep quantity and quality, and sleep environment, including light and temperature. Generalised linear modelling will be applied to examine the relationships between sleep environment factors and sleep metrics. Various covariates, known to influence sleep, will be included in the statistical models.
The results from this study will contribute to the understanding of the impact of the on-site and at-home sleep environments on the sleep of shift workers in extractive industries. Furthermore, the results will inform strategies for the development and improvement of on-site accommodation and at-home sleep environment.
P031 A Novel Oral Appliance Implementation Protocol Using Nightly Portable Monitoring for OSA Patients Failing CPAP therapy
Authors: Ling I , Christoforou J , Chin G , Currie P 
Published: October 2023

Abstract

Introduction
Oral Appliance Therapy (OAT) is an effective second line treatment for OSA. However, OAT devices do not have active efficacy monitoring, hence little is known about methods to best identify the optimal degree of mandibular advancement.

Methods
Consecutive OSA patients undergoing OAT at a sleep disorders service were recruited to participate in a novel titration protocol using nightly monitoring via a portable device (NightOwl®, Ectosense, Belgium). Demographic & sleep study (PSG) data, and key NightOwl® metrics were collected. A treatment PSG was conducted at conclusion of OAT implementation using identified optimal point of mandibular advancement.

Results
80 subjects were recruited (52 male, 65%) with mean (±SD) age 49±12 years, BMI 28±4.4 kg/m2, Epworth score (ESS) 9.1±4.9. Baseline PSG showed mean AHI 28±20 events/hr, nadir SpO2 84±21%, time SpO2&lt;90% 8.3±30 minutes. Blood pressure monitoring at baseline showed mean day BP 123/70mmHg and night BP 106/57mmHg. The mean mandibular advancement implemented was 2.9±1.7mm.
Post treatment mean ESS was 5.1±3.5 (p&lt;0.001). 62/68 (91%) subjects reported perceived benefit on OAT, 49/53 (92%) reduced snoring, 51/62 (82%) improved sleep, 49/62 (79%) increased energy. Treatment PSG on completion of the protocol showed AHI 14±10 events/hr (p&lt;0.001), nadir SpO2 82±33% (p&gt;0.05), time SpO2&lt;90% 1.2±21 minutes (p=0.04). 48/63 (76%) met the AHI definition of OAT success.

Discussion
This study demonstrates a novel OAT protocol which led to minimal degree of mandibular advancement, resulting in high rates of symptom benefit and effective treatment of OSA.
P040 Comparisons of Heart Rate Variability Indices Derived from the Sheet-type Device beneath the Mattress with those from the Electrocardiogram
Authors: Yanagisawa N , Nishizaki Y , Kasai T 
Published: October 2023

Abstract

Introduction
A sheet-type device beneath the mattress was developed for non-invasive monitoring of cardiac rhythm during sleep and in bedridden end-of-life elderly patients, enabling the acquisition of ballistocardiography (BCG) signals. BCG represents minute vibrations in the body associated with cardiac ejection of blood and has recently been utilized to estimate heart rate variability (HRV) indices. This study aimed to compare HRV indices derived from BCG with those obtained from simultaneously measured electrocardiogram (ECG) and assess their agreement.

Methods
Healthy subjects (14 males, 11 females; age 40.6±12.8 yrs.) were recruited between August 2022 and April 2023. Subjects laid on a bed with the device placed under their pillow, while ECG was recorded for 20 minutes. Time-domain indices (mean normal-to-normal (NN) interval) and frequency-domain indices (low frequency (LF) and high frequency (HF)) were calculated, and linear associations were examined by correlation analysis. Bland-Altman analysis was employed to evaluate the agreement between the indices.

Results
Significant positive associations were observed between BCG and ECG indices in mean NN interval (r=0.994, p&lt;0.001) and LF (r=0.685, p&lt;0.001) and HF (r=0.687, p&lt;0.001). Bland-Altman analysis demonstrated good agreement in mean NN (mean of pairwise difference (MPD): 1.07; limits of agreement (LA): -12.57-14.70; ratio: 0.01), but poor agreement in LF (MPD: -4.32; LA: -30.42-21.78; ratio: 0.63) and HF (MPD: 4.29; LA: -21.70-30.28; ratio: 0.45) based on the ratios (&gt; 0.2).

Conclusion
The high correlation and good agreement between mean NN intervals suggest that the BCG device can serve as an alternative to HRV for estimating NN interval.