bluuebunny/crossref_metadata_2025_split huggingface dataset:
O012 A prospective evaluation of the nature and time course of sleep disordered breathing and respiratory failure in patients with motor neurone disease (MND): the BreatheMND-1 study
Authors: Aiyappan V , Catcheside P , Antic N , Grivell N , Hansen C , Schultz D , Graham K , Allcroft P , Glaetzer K , McEvoy D 
Published: October 2021

Abstract

Introduction
Sleep disordered breathing (SDB) is a well-recognised but heterogeneous complication in MND and may herald the onset of respiratory failure. This study examined the nature and time course of SDB, sleep disruption and respiratory failure in MND patients.

Methods
The BreatheMND-1 study recruited MND patients for prospective evaluation of muscle strength,supine and prone dyspnea, quality of life, pulmonary function, arterial blood gas and polysomnographic sleep measurements at baseline and, where possible, 3, 6 and 12 months for exploratory analyses.

Results
35 MND patients completed baseline and 25 at least one follow-up visit (median [IQR] follow-up time 8.7 [7.1–10.2] months). At baseline, patients were aged 64 [55–70] years, 16/35 (46%) female, with reduced FVC (77[59–92] %predicted) but relatively normal BMI (26.2[23.7–27.7] kg/m²) and PaCO2 (38.8[37.0–42.1] mmHg). At baseline and last follow-up, the prevalence of respiratory failure (PaCO2&gt;45 mmHg or HCO3&gt;27 mmol/l) was 9/33 (27%) and 12/27 (44%) respectively (p=0.186). Total sleep time and sleep efficiency were poor at baseline (5.2[4.6–5.9] h and 67.6[63.0–78.8]%) and declined at follow-up (by 1[0.3–1.9] h, p=0.020 and 7.9[-2.3–14.2]%, p=0.017 respectively). AHI was 7.2[2.8–14.6] /h and remained unchanged. In regression model,sleep time and efficiency were not predictive of respiratory failure, but the percentage of deep and REM sleep at last follow-up were (ROC area under curve 0.73±0.11, p=0.048 and 0.84±0.09, p=0.001).

Discussion
Sleep quality in MND is remarkably poor, irrespective of SDB, and could reflect and/or impact MND progression. Thus, further strategies to monitor & improve sleep are clearly warranted in patients with MND.
O013 The pathogenesis of obstructive sleep apnea in individuals with comorbid insomnia and obstructive sleep apnoea (COMISA)
Authors: Brooker E , Thomson L , Landry S , Edwards B , Drummond S 
Published: October 2021

Abstract
Obstructive sleep apnea (OSA) and Insomnia are prevalent sleep disorders which are highly comorbid. This frequent co-occurrence suggests a shared etiology may exist. OSA is caused by the interaction of four pathophysiological traits: a highly collapsible upper airway, elevated loop gain, a low arousal threshold, and poor muscle compensation. No study has ascertained whether these traits are influenced by insomnia. We aimed to quantify the four traits which contribute to OSA in individuals diagnosed with comorbid insomnia and OSA (COMISA). We non-invasively determined these traits in 52 COMISA patients (Age: 56±14 years) with mild-to-severe OSA (AHI=21.2±10.63 events/h) using polysomnography. Our results indicated that 83% of COMISA patients had a low arousal threshold and only 2% of patients exhibited a highly collapsible airway using previously defined thresholds. Multiple linear regression revealed the arousal threshold (b=0.24, 95%CI[0.11, 0.37], β=0.47, p&lt;0.001) and loop gain (b=23.6, 95%CI[7.02, 40.18], β=0.33, p&lt;0.01) were the strongest predictors of OSA severity in our sample. There was no significant relationship between the arousal threshold and insomnia severity measured by the insomnia severity index (ISI). Further work is being performed to compare these findings with a matched sample of OSA only participants. Our preliminary findings demonstrate OSA in COMISA is characterized by a mildly collapsible airway/low arousal threshold phenotype and is largely driven by non-anatomical factors including a low arousal threshold and high loop gain. OSA treatments which are effective in patients with mild anatomical compromise and raise the arousal threshold may provide therapeutic benefit in COMISA patients.
O018 Changes in sleep parameters in children with Down Syndrome following treatment
Authors: Chawla J , Burgess S , Heussler H 
Published: October 2021

Abstract

Introduction
There is limited evidence about how sleep changes in children with Down syndrome (DS) following sleep interventions. This study evaluated changes in sleep over time in children receiving treatment comparing to a control group who did not.

Methods
Children with DS, 3-16yrs, attending the sleep clinic were followed for 24-months. Sleep parameters including parent completed child sleep habits questionnaire (CSHQ), PSG and home sleep diary were obtained pre and post sleep interventions for children undergoing treatment. Data was obtained at similar intervals for the control group who were followed over the same time period.

Results
Data was obtained for 41 participants, 16 children received an intervention and 25 did not. Interventions included ENT surgery (7), CPAP (4), melatonin (3) or a combination (2). The intervention group had a significantly higher average total CSHQ score overall than those in the control group (0.01). Scores decreased over time but remained higher than in controls throughout, and were clinically significant in both groups (&gt;41). Sleep diary estimated average total sleep duration did not differ between groups and was 10hrs/night. PSG showed improvement in OAHI in those children undergoing pre and post intervention studies.

Discussion
Evaluation of sleep parameters in this referred cohort of children with Down syndrome demonstrates total sleep duration in keeping with national recommendations and improvement in obstruction with treatment. However, CSHQ results indicate ongoing sleep difficulties reported by parents, despite standard sleep interventions. This may reflect persisting non-respiratory sleep disorders, which are not being adequately addressed at present.
O034 Rockabye sailor: investigating the impact of simulated motion on sleep and cognitive performance
Authors: Matthews R , Fraysse F , Daniell N , Schumacher P , Banks S 
Published: October 2021

Abstract

Background
Many naval vessels are designed with sleeping berths orientated in a fore/aft direction. Reorientating the berths changes the rocking from side-to-side to head-to-foot. It is unknown what effect rocking orientation may have on sleep.

Aim
This study aimed to investigate the impact of a simulated fore/aft orientation (side-to-side motion) with a simulated athwartships berth orientation (head-to-foot motion), on sleep quality and quantity, and cognitive performance.

Method
21 participants (13M/8F; 24.0±4.8 years; BMI 21.1±2.5) slept in berths on a motion platform replicating vessel motion. In a repeated measures design, each participant slept under three conditions in randomised order: 1) no motion, 2) fore/aft orientation (side-to-side motion), and 3) athwartships orientation (head-to-foot motion). Measurements of sleep (ambulatory polysomnography), sleepiness (Karolinska Sleepiness Scale: KSS), and vigilance (Psychomotor Vigilance Test: PVT) were analysed using Mixed Effects ANOVA.

Results
Participants’ total sleep time was shorter (p&lt;0.001), sleep efficiency was reduced (p&lt;0.001), they woke more frequently (p&lt;0.001), and their sleep contained less REM (p&lt;0.001) in the athwartships orientation (head-to-foot motion) compared to the no motion, and fore/aft orientation (side-to-side motion) conditions. Participants’ also reported significantly higher sleepiness on KSS (p=0.006), poorer subjective sleep quality (p&lt;0.001), and displayed worse vigilant attention on PVT (p=0.03) following the athwartships orientation compared to the two other conditions.

Discussion
The simulated athwartships bunk orientation (head-to-foot motion) negatively impacted sleep and cognitive performance. These results may have implications for crew wellbeing. The data also gives unique theoretical insight into the effects of different types of rhythmic movement on sleep.

Funding
DSTG
O041 The impact of including oxygen desaturations occurring during awake epochs on the oxygen desaturation index
Authors: Whenn C , Wilson D , Churchward T , Ruehland W , Worsnop C , Tolson J 
Published: October 2021

Abstract

Introduction
The oxygen desaturation index (ODI) is an important measure of sleep disordered breathing during polysomnography (PSG) however there is no accepted standard for its calculation. The AASM Manual for the Scoring of Sleep and Associated events (V2.6) does not specify whether oxygen desaturations occurring during awake epochs should be included. More generally, epoch-based scoring is potentially problematic for accurate ODI calculation. This study aims to compare the calculation of ODI including and excluding oxygen desaturations occurring during awake epochs and to determine the impact of sleep efficiency (SE) on any discrepancy.

Methods
Using twenty-one consecutive unattended PSG’s for investigation of OSA, two oxygen desaturation indices were calculated from each PSG; one excluding (ODIsleep) and one including (ODIall) oxygen desaturations marked in awake epochs.

Results
The median (IQR) ODIall was 19.3/h (10.3, 27.0) and ODIsleep was 13.0/h (6.6, 16.7). The median (IQR) difference (ODIall - ODIsleep) was 5.2/h (2.7, 10.4). This difference was greater with decreasing SE (r = -.63, p = .002). Patients with SE ≤ 75% (n=10) had a median ODI difference of 11.5/h (4.0, 17.6), and those with SE &gt; 75% (n=11) had a difference of 2.8/h (2.0, 5.5) (p = .02).

Discussion
ODI was greater when including oxygen desaturations during awake epochs, with this discrepancy being greatest when SE is ≤ 75%. We plan to confirm these findings in a larger sample. This investigation informs clinical practice, highlights the difficulties of epoch scoring, and informs future standards for the scoring of sleep and associated events.
O042 Impact of supine REM AHI on diagnostic sleep studies for OSA
Authors: Callum J , Stranks L , Melehan K , Yee B 
Published: October 2021

Abstract

Introduction
A conventional belief is that REM exacerbates positional OSA (POSA). Subsequently, PSGs often report on presence of supine REM with the presumption that without supine REM, the AHI may be underestimated. This study explores the impact of REM upon obstructive respiratory events in sleep when supine.

Methods
From 1/1/2019 through 31/12/2020 PSGs for OSA diagnosis performed using Sleepware G3 were reviewed. A subgroup analysis was conducted within POSA patients defined as 1) total AHI&gt;10/hour and non-supine AHI&lt;10/hr, 2) supine AHI&gt;2x non-supine AHI and 3) at least 15min of supine and non-supine sleep. Data was analysed with Pearson’s Chi Squared Test using Stata 16.1.

Results
Supine REM occurred in 97% of the 467 PSG’s. The supine REM AHI was 32.1(95%CI 29.1–35.2), compared to supine NREM AHI of 36.6(33.5–39.6), non-supine REM AHI of 21.3(18.8–23.9) and non-supine NREM AHI of 19.9(17.3–22.5).
Among 109 POSA patients the supine REM AHI was 31.7(26.1–37.4) compared to 28.9(24.8–32.9) in supine NREM, 9.5(6.1–12.9) in non-supine REM and 3.5(3.0–4.0) in non-supine NREM.
The average duration of obstructive respiratory events was 27.3 seconds (26.2–28.5) in REM compared to 23.5 seconds (22.8–24.2) in NREM. This statistically significant difference did not persist in POSA patients.

Discussion
The results do not support an additive effect of REM beyond supine positioning among patients with POSA, however there is evidence that REM lengthens respiratory events, which may reduce AHI. In the POSA subgroup analysis, there was an increased AHI in REM compared to NREM only in the non-supine position.
O043 “My Fitbit tells me I don’t sleep” – Validation of a consumer-wearable device (Fitbit Charge 3TM) using gold standard in-laboratory polysomnography to assess sleep in adults presenting for medical evaluation in a sleep laboratory
Authors: Munsif M , Jumabhoy R , Rangamuwa K , Mansfield D , Drummond S , Dabscheck E 
Published: October 2021

Abstract

Background
There has been a rapid growth in wearable devices marketed for sleep. Trackers such as the Fitbit collect data through an accelerometer and use heart rate variability to estimate the sleep-wake state. Currently, Fitbit validation studies have only been with “healthy” adults and Insomnia Disorder.

Aims
The purpose of this study is to evaluate the accuracy of Fitbit Charge3TM compared to in-lab polysomnography (PSG) in patients with sleep disorders. Our hypothesis is that Fitbit Charge 3TM will perform with less sensitivity and specificity relative to PSG in the presence of sleep disorders.

Methods
A prospective study of patients attending a PSG through Epworth Camberwell Sleep Lab between 2019–2021 will be conducted. Fitbit Charge3TM will be worn on the wrist with concurrent PSG monitoring.
Parameters measured with both PSG and Fitbit Charge3TM will include total sleep time, Sleep onset latency, wake after sleep onset and time spent in N1, N2, N3 and REM sleep (min). Standard PSG data will be evaluated to diagnose sleep-disordered breathing.
Progress to date:Ethics approval has been obtained, and 110 participants have been recruited. 30-second epoch-by-epoch analysis will now be conducted. Bland-Altman analyses will be performed to assess agreement between the Fitbit and PSG.
Intended outcome and impact: Our novel study findings will provide evidence to address queries regarding the accuracy of the Fitbit trackers to evaluate sleep and may support the use of Fitbit Charge3TM as an initial screening device to assess sleep duration and sleep architecture in select patients.
O045 Anxiety and daytime sleepiness scores have a weak but statistically significant correlation with apnoea-hypopnoea index
Authors: Lachowicz J , Kee K , Wallbridge P , Stonehouse J , Perkins A 
Published: October 2021

Abstract

Background
Previous datasets demonstrate inconsistent relationships between apnoea-hypopnoea index (AHI) and questionnaire measures of daytime sleepiness, anxiety and depression.

Methods
1149 consecutive diagnostic polysomnograms at a quaternary hospital were retrospectively analysed (2020–2021). Relationships between age, sex, AHI, Epworth Sleepiness Scale (ESS) and Hospital Anxiety and Depression Scales (HADS-A and HADS-D) were reviewed.
Progress to date:Mean age was 47.8+/-15.7 years, with male gender bias (59%). 49.9% had elevated HADS-A (&gt;7; mean 8.1+/-4.5). 33.7% had elevated HADS-D (&gt;7; mean 6.2+/-4.0). 29.6% had sleepiness (ESS &gt;10; mean 7.9+/-5.0). Mean AHI was 23.5+/-27.9 events/hour. 69.7% had obstructive sleep apnoea (OSA); 45.0% were moderate-severe (AHI &gt;14/h).
HADS-A (9.1 versus 7.3; P&lt;0.001; 95% CI [-2.32, -1.25]), HADS-D (6.9 versus 5.8; P&lt;0.001; 95% CI [-1.62, -0.67]) and ESS (8.2 versus 7.7; P=0.039; 95% CI [-1.21, -0.03]) were higher in females. Males had greater OSA severity (AHI 27.0/h versus 18.6/h; p&lt;0.001; 95% CI [5.15, 11.67]).
Pearson’s tests demonstrated a statistically significant but weak positive correlation between AHI and HADS-A (P=0.021, R=0.07, N=1096), and AHI and ESS (P=0.042, R=0.06, N=1135). AHI and HADS-D showed no correlation. ESS weakly correlated with HADS-A (P&lt;0.001, R=0.237, N=1104).
Intended outcome and impact:Severity of sleep apnoea as defined by AHI only explains a small proportion of the variance in daytime sleepiness and anxiety as measured by the ESS and HADS-A, respectively, with weak linear relationships demonstrated. Neither ESS nor HADS-A were helpful in predicting the presence of OSA. Further study is required to determine optimal polysomnographic correlates of sleep apnoea symptoms.
O046 Association of sleep characteristics with low muscle strength: the Hypnolaus cohort study
Authors: Piovezan R , Yu S , Hirotsu C , Marques-Vidal P , Visvanathan R , Heinzer R 
Published: October 2021

Abstract

Background
Muscle deterioration is a hallmark of aging and sleep may play a role in the development of sarcopenia. Population-based studies including objective evaluation of sleep characteristics and disorders may provide evidence of how sleep affects muscle function across adulthood. We aimed to evaluate associations of sleep characteristics with handgrip strength in a population-based cohort study.

Methods
Participants of the HypnoLaus study (Lausanne, Switzerland) aged &gt;40 years were cross-sectionally evaluated through questionnaires and PSG. Muscle strength was assessed by hand dynamometer and low muscle strength (LMS) was defined according to the criteria for sarcopenia (&lt;27 kg for men, &lt;16 kg for women). Multivariate logistic regression analysis controlling for potential confounders wereapplied.

Results
1902 participants (mean [SD] age, 57.4 [10.5] years; 968 [50.9%] female) were enrolled. LMS was detected in 95 (5.0%) participants. After controlling for sociodemographic characteristics, lifestyle factors, and comorbidities, objectively measured long sleep duration (&gt;8h) was independently associated with LMS (OR=2.41, 95%CI=1.36–4.27). Subjective measures of sleep duration and quality, excessive daytime sleepiness, and other sleep characteristics obtained by PSG were not associated with LMS.

Conclusions
Objectively measured long sleep duration rather than short sleep duration was associated with LMS in a population-based study including participants aged &gt;40 years. Self-reported sleep duration was not associated with LMS. The findings suggest long sleep duration measured by PSG is a potential risk factor for sarcopenia and should be considered as a target in preventive and therapeutic strategies against the development of muscle health decline observed with aging.
O047 Sleep quality and fatigue in children and adolescents with multiple sclerosis
Authors: Tran J , Yiu E , Vandeleur M , Adams A 
Published: October 2021

Abstract

Background
Fatigue is common in children and adolescents with multiple sclerosis (MS) and its aetiology is assumed to be multifactorial, however, its relationship to sleep quality in this population remains unknown. This study aims to examine the prevalence of fatigue and sleep disturbance in this population and their relationship to mood, quality of life, physical activity, and MS disease characteristics.

Methods
Children with pediatric onset multiple sclerosis (POMS) aged 0–18 were recruited. Subjective sleep quality was assessed by the Pediatric Daytime Sleepiness Scale (PDSS), Sleep Disturbance Scale for Children (SDSC) and OSA-18. All children were referred for polysomnography (PSG) including transcutaneous CO2 and video monitoring. Fatigue was assessed using the PedsQL Multidimensional Fatigue Scale (PedsQL-MFS).
Progress to date: Fifteen children with relapsing remitting MS (mean age 15.73±1.44, mean EDSS score 1.11±1.12) have been enrolled to date. 73% of children were fatigued according to the PedsQL-MFS (mean transformed score 52.04). 67% and 60% of children scored higher than the clinical cutoff for the PDSS (17.87) and SDSC (42.73) respectively. However, all children scored within the normal range for the OSA-18 (34.00). To date, eleven children have completed PSG.
Intended outcome and impact: This is the first study utilising PSG to objectively assess sleep quality in children with POMS. Findings from this study will document the magnitude of sleep disturbance in this population and have implications for the management of fatigue and other related impairments observed in paediatric MS.
P026 Sleep during the transition to shift work: Preliminary findings of a longitudinal field study of commencing paramedics
Authors: Crowther M , Ferguson S , Adams R , Reynolds A 
Published: October 2021

Abstract
Paramedics are at increased risk of occupational injuries, mental illness and poor health outcomes. Little is known however about the role of poor sleep in such outcomes and the way in which sleep may change as an individual commences work as a paramedic. The aim of the present study is to investigate changes in sleep as paramedics commence work.
As part of an ongoing, longitudinal study of Australian paramedics, participants undertake a baseline assessment prior to commencing work and a follow up every three months for a year. At each time point paramedics wear an actigraph (GENEActiv) for seven days, and complete an online survey including the Pittsburgh Sleep Quality Index (PSQI). The present preliminary analysis utilised linear mixed models to test the effect of commencing work as a paramedic on participants’ sleep quality.
Preliminary results from the first cohort of recruits are reported (n=9 commencing paramedics, mean age (+SD) = 25.2±4.4, 56% female). There was a significant increase in PSQI scores from baseline (T0: 2.4±1.4) to three months (T1: 5.2±3.9) (F(1, 8) = 5.47, p = 0.05). The percentage of individuals with clinically poor sleep (PSQI ≥5) increased from 0% (n=0) at T0 to 56% (n=5) at T1.
Commencing paramedics report significantly poorer sleep quality compared to their pre-commencement levels. Interestingly, baseline PSQI scores indicate no participants were experiencing clinically defined poor sleep. However, at follow-up over half the sample reported clinically defined poor sleep. Findings of objective sleep and wake outcomes are anticipated for the meeting in October.
P034 Inter-scorer concordance impacts MSLT results
Authors: Eriksson N , Teuwen P , Mateus E , Shim C , Scott A 
Published: October 2021

Abstract

Introduction
A retrospective study on the effect of inter-scorer concordance and impact of analysing polysomnography (PSG) data prior to the Multiple Sleep Latency Test (MSLT) on clinical interpretation of Narcolepsy (N) and Idiopathic Hypersomnolence (IH).

Methods
Data of four individuals was randomly selected from a cohort of patients that participated in MSLT studies. De-identified MSLT fragments from four nap periods (n=16) were scored in two groups: analysis of PSG conducted prior to the respective MSLT fragments, and analysis without access to prior PSG. Individual scorers were compared to a master score set, by consensus from two experienced sleep scientists.
Spearman correlation and percentage agreement statistics were applied to calculate the inter-scorer concordance in sleep latency and REM latency. Mann-Whitney test was utilised to assess differences between the two groups. A positive result was assigned as: mean (n=4) sleep latency of &lt;10min (IH), and mean (n=4) sleep latency of &lt;8min including (n=2) SOREMs (N).

Results
From 16 sets of data, four false positive results were identified when PSG was not analysed prior to scoring the MSLT fragments. Additionally, statistically significant differences were present when PSG analysis was conducted prior to scoring MSLT sleep latency and REM latency data.

Discussion
These results support a recommendation that PSG analysis (sleep and REM latency) should be encouraged prior to MSLT studies and performed by the same sleep scientist. Furthermore, including MSLT data in intra-lab concordance activities is important, particularly in relation to medical interpretation and practice.