bluuebunny/crossref_metadata_2025_split huggingface dataset:
0551 Longitudinal Measurement Invariance of the Insomnia Severity Index in Veterans with Sleep Apnea
Authors: Wohlgemuth W , Fins A , Tutek J , Gonzalez A , Martinez-Garcia A , Satyanarayana S , Marchetti D , Wallace D 
Published: May 2020

Abstract

Introduction
The Insomnia Severity Index is a commonly used instrument to assess the presence of insomnia symptoms as well as an outcome measure following an intervention. Longitudinal measurement invariance is a necessary property of an assessment instrument when it is repeated over time. The validity of conclusions regarding change in the construct ‘insomnia severity’ depend on scale equivalence at each measurement timepoint. Assessment of measurement invariance of the ISI in sleep apnea patients has never been performed.

Methods
Veterans with sleep apnea (n=654; AHI=36±28; 93% male; age=52±12; BMI=33±6) completed the ISI on the night of their overnight PSG and again when they picked up their PAP device. Invariance was determined by imposing a series of more restrictive equivalence constraints on a 2-factor model of the ISI. The series of constraints tested for configural, weak, strong and strict invariance. Invariance testing was modeled with exploratory structural equation modeling in Mplus (v. 7.0).

Results
The 2-factor model that emerged from the analysis showed items relating to nighttime symptoms loading on factor 1 and daytime symptoms loading on factor 2. The sleep ‘satisfaction’ item, however, had weak but similar loadings on both factors. The increasingly restrictive constraints imposed on the model revealed no decrement in model fit (RMSEA=.039 to.043; CFI=.987 to .980; TLI=.981-.977; SRMR=.027-.041).

Conclusion
The ISI met strict criteria for longitudinal measurement invariance demonstrating that it is a valid instrument to be used in repeated measures study designs of insomnia in sleep apnea patients. Change over time on the ISI is not due to the changing measurement characteristics of the ISI but to true changes in the ‘insomnia severity’ construct.

Support
None
0555 The Relationship Between Sleep Efficiency and Apnoea Hypopnoea Index (AHI) in Adult Obese Males
Authors: Ankita A , Mehta B , Dutt N , Sharma P 
Published: May 2020

Abstract

Introduction
Prevalence of obesity is increasing worldwide. According to OECD 2017, the prevalence of obesity is 19.5% worldwide. Obesity leads to disturbed sleep due to complete or partial obstruction of upper airways i.e. obstructive sleep apnoea. This disturbed sleep leads to increased sympathetic discharge & further obesity and thus forms a vicious cycle of obesity disturbing sleep and sleep disturbance increasing obesity. The purpose of the present study was to correlate the sleep efficiency with apnoea hypopnea index (AHI) in adult obese males.

Methods
Nineteen adult obese males (26 years- 60 years), non-smokers were recruited for this cross-sectional study. The obesity criteria was taken as BMI ≥ 25 kg/m2. They underwent an overnight polysomnographic examination with total 68 channels and 32 EEG inputs. The episodes of apnea were defined as complete cessation of airflow for ≥10 s, and hypopnea consisted of a ≥30% reduction in oronasal airflow accompanied by a reduction in oxygen saturation measured by pulse oximetry of at least 4%. AHI was determined by the frequency of these events per hour during sleep time based on the results of the overnight polysomnography. Sleep efficiency index was calculated by dividing total duration of sleep stages (N1+ N2+ N3+ REM) by total time in bed.

Results
We tested for normality through Shapiro Wilk test and our data was found to be non-parametric. Hence Spearman correlation between sleep efficiency and AHI was performed. The correlation was non- significant with p value 0.1245 and r = - 0.365. The correlation of BMI with sleep efficiency was significant (p= 0.0195) with r value= -0.5303.

Conclusion
The results conclude that the sleep efficiency worsens with obesity. Although the correlation between AHI and sleep efficiency was not found significant, a negative r value indicates that the sleep efficiency decreases with increased obstructive events during sleep.

Support
All India Institute of Medical Sciences Jodhpur
0562 Differences in Upper Airway Soft Tissue Volumes Between African American and Caucasian Patients with Obstructive Sleep Apnea Using Magnetic Resonance Imaging
Authors: Webster J C , Keenan B , Schwab R J 
Published: May 2020

Abstract

Introduction
Research suggests greater obstructive sleep apnea (OSA) severity in African-Americans than Caucasians. However, the underlying mechanisms causing this ethnic disparity are unknown. To evaluate possible mechanisms, we compared the size of the tongue between African American and Caucasian OSA patients using magnetic resonance imaging (MRI), controlling for age, body mass index (BMI) and apnea-hypoxia index (AHI). Given prior evidence of more severe OSA in African Americans, we hypothesized these patients would have larger soft tissue volumes compared to Caucasians.

Methods
Upper airway soft tissue volumes, (total tongue, tongue fat, lateral walls, pterygoids, total soft tissue) were quantified using MRI and compared between Caucasian (n=133) and African American (n=175) patients with moderate OSA. Analyses were conducted using regression models controlling for age, sex, BMI and AHI.

Results
Among all OSA patients, African Americans had higher BMI than Caucasians (40.0±8.6 vs. 37.1±8.1 kg/m2, p=0.0024) and a higher proportion of females (66.3% vs. 36.1%; p&lt;0.0001). There were no significant differences in age (p=0.143) or AHI (p=0.314). Controlling for these covariates, there were no differences between African American and Caucasian OSA patients in tongue fat volume (mean [95% confidence interval] difference = 479 [-3156, 4115] mm3; p=0.794). However, African Americans had a 13,286 (6,439, 20,132) mm3 larger total tongue volume compared to Caucasians (p=0.0002). Larger volumes in African Americans were also observed for the soft palate (p&lt;0.0001), retropalatal lateral walls (p=0.003), pterygoid (p=0.034) and total soft tissue volume (p=0.0003).

Conclusion
African Americans were observed to have larger volumes of the tongue, soft palate, retropalatal lateral walls, pterygoids and total soft tissue volume compared to Caucasians, although there were no differences in AHI and tongue fat volume. The study contributes to the overall understanding of ethnic-specific pathology of OSA and can potentially influence how African Americans and Caucasians are diagnosed and treated specifically for the disease.

Support
0567 Hypoxic Burden and Apnea-Hypopnea Duration in Patients with Positional Obstructive Sleep Apnea
Authors: Ramzy J A , Rengan R , Mandal M , Rani S , Vega Sanchez M E , Jaffe F , D’Alonzo G , Shariff T , Chatila W , Weaver S , Krachman S 
Published: May 2020

Abstract

Introduction
Recently, the measurement of the hypoxic burden and apnea-hypopnea duration has been shown to correlate with mortality in patients with obstructive sleep apnea (OSA). We hypothesized that in patients with mild positional OSA (apnea-hypopnea index [AHI] &lt; 5 events/hr in the non-supine position) the hypoxic burden would be increased and apnea-hypopnea duration shortened and similar to patients with non-positional OSA.

Methods
Fourteen patients with positional OSA and 24 patients non-positional OSA with similar severity of OSA based on the respiratory event index (REI) were included. All patients had a home sleep apnea test for suspected OSA. The hypoxic burden was calculated by the multiplication of REI and the mean area under the desaturation curves.

Results
Thirty-eight patients [12 (35%) males, 50±12 yrs, BMI 35±7 kg/m2, Epworth Sleepiness Scale (ESS) 11±8, REI 10±3 events/hr, apnea-hypopnea duration 19±4 sec, mean SaO2 94±2%, lowest SaO2 79±8%, % total sleep time (TST) SaO2 &lt; 90% 11±16%, hypoxic burden 30±17 %min/hr] completed the study. Fourteen patients [9 (64%) males, 46±14 yrs, BMI 31±6 kg/m2, ESS 7±5, REI 9±3 events/hr, mean SaO2 94±2%, lowest SaO2 81±6%, %TST SaO2 &lt; 90% 4±6%] had positional OSA (supine REI 16±7 events/hr, non-supine REI 3±1 events/hr) and 24 patients had non-positional OSA [3 (13%) males, 52±10 yrs, BMI 38±7 kg/m2, ESS 12±9, REI 10±3 events/hr, mean SaO2 94±2%, lowest SaO2 77±9%, %TST SaO2 &lt; 90% 14±19%]. The hypoxic burden was elevated in both the positional and non-positional OSA patients with no difference between the groups (26±19 %min/hr and 32±15 %min/hr, respectively, p=0.13). The apnea-hypopnea duration was similar in positional and non-positional OSA patients (20±3 sec and 18±4 sec, respectively, p=0.08 sec).

Conclusion
In patients with mild positional OSA the hypoxic burden, which has been associated with cardiovascular mortality, is elevated and similar to patients with non-positional OSA.

Support
None
0573 Screening for Obstructive Sleep Apnea at Home Based on Deep Learning Features Derived from Respiration Sounds
Authors: Romero H E , Ma N , Hill E A , Brown G J 
Published: May 2020

Abstract

Introduction
Analysis of sleep breathing sounds has been employed to screen obstructive sleep apnea (OSA). However, most current methods rely on specialized equipment (e.g., tracheal microphones), require additional physiological data (e.g., oxygen saturation), are rule-based, or are trained on data collected in-lab, making them less suitable for home use. In this study, deep learning methods were leveraged to explore the hypothesis that sleep audio recordings collected via smartphones can be used alone to screen for OSA by exploiting the temporal pattern of respiration sounds.

Methods
Adult participants with suspected sleep-disordered breathing of varying degrees of severity were recruited from the general population and from GP referrals to sleep clinic. Audio recordings were collected via smartphones during home sleep apnea testing (HSAT). HSAT data were scored by a registered polysomnographic technologist in accordance with current international guidelines (AASM V2.5, 2018) and used as reference. To exploit acoustic respiration temporal pattern, time interval histograms were computed for sequences of audio-words that were automatically learned from spectral features with a deep neural network. Means and standard deviations of the time intervals for each audio-word were employed by a Gaussian mixture model to classify 2-minute audio recording segments as either containing OSA events or not.

Results
Preliminary data from 4 valid nights’ recordings obtained from 2 consented participants was analysed. 550 segments were used for training, with 180 segments used for evaluation. Audio recording demonstrated a sensitivity of 0.71 and specificity of 0.66 when compared with manually-scored HSAT.

Conclusion
Preliminary results suggest that an approach to OSA screening based on deep learning with inter-audio-word intervals to capture information about respiration temporal pattern may be a useful tool in diagnosis of OSA. Further model development is underway using data collected from up to 200 patients and full study data will be presented.

Support
The project is supported by an Innovate UK grant (project number 157358). HR is supported by a joint scholarship from Passion for Life Healthcare Ltd and University of Sheffield. LH acknowledges the financial support of NHS Research Scotland (NRS), through NHS Lothian.
0575 Sleep Monitoring with a Single Channel EEG Recorder in Patients with Psychiatric Disorders
Authors: Miyata S , Iwamoto K , Banno M , Ito Y , Noda A , Ozaki N 
Published: May 2020

Abstract

Introduction
The gold standard of sleep measurement has been laboratory polysomnography (PSG). However, electrodes and cables can cause discomfort, and exposure to an unfamiliar environment can cause the “first-night effect.” Difficulty falling asleep or maintaining sleep, poor sleep quality, and nightmares are some of the key clinical symptoms observed among individuals with psychiatric disorders. Those suffering from sleep disorders often present with symptoms of discontent with regard to sleep quality, timing, and quantity, and these symptoms have an adverse impact on function and quality of life. A minimally invasive technique would be preferable in patients with psychiatric disorders, who tend to be sensitive to environmental change. Accordingly, we evaluated the performance of a single-channel electroencephalography (EEG)-based sleep monitoring system in patients with psychiatric disorders.

Methods
Fifty-nine patients undergoing PSG were enrolled in this study. Single-channel EEG sleep monitoring was performed simultaneously with PSG. PSG and the EEG recordings were used to evaluate sleep parameters, such as total sleep time (TST), sleep efficiency, rapid eye movement (REM) sleep, light sleep (stages N1 and N2), and deep sleep (stage N3). Correlation analysis was used to evaluate the agreement on sleep parameters and attributing factors to the inaccuracies of the single-channel EEG recording.

Results
TST, sleep efficiency, REM sleep duration, and non-REM sleep duration of the single-channel EEG-based sleep monitoring showed a significant correlation with those of PSG. Lower sleep efficiency, a decrease in REM sleep, and increases in waking after sleep onset, arousal index, and apnea/hypopnea index were associated with the difference of sleep parameters between the two methods.

Conclusion
Among patients with psychiatric disorders who are sensitive to environmental change single-channel EEG sleep monitoring would be a useful technique to objectively evaluate sleep quality.

Support
Collaboration study with The KAITEKI Institute, Inc.
0582 Examining OSA Screening and Treatment for Individuals on a PTSD and Alcohol Disorder Residential Treatment Unit
Authors: Colvonen P J , Rivera G , Haller M , Norman S 
Published: May 2020

Abstract

Introduction
Obstructive sleep apnea (OSA) is highly co-occurring with both alcohol use disorder (AUD) and posttraumatic stress disorder (PTSD) and has been shown to interfere with both PTSD and AUD outcomes. However, OSA often goes undiagnosed and untreated in residential treatment facilities. Our study aimed to assess the feasibility of incorporating OSA screening and treatment onto a substance abuse residential rehabilitation treatment program (SARRTP). Further, we examine the relationship between adherence rates of CPAP on PTSD outcomes.

Methods
Participants were 35 consecutive veterans admitted to the SARRTP PTSD track who consented to screening. Veterans were on the unit for 4-6 weeks. OSA was diagnosed using Nox T3 recorders, a Type-3 portable OSA screener (using Apnea Hypopnea Index &gt;= 5). Insomnia Severity Index and PTSD checklist were given at pre- and post-treatment.

Results
64.7% of Veterans screened positive for OSA. 11.8% were previously diagnosed with OSA, but did not use a CPAP machine; 17.6% were previously diagnosed and were using a CPAP machine; and 35.3% were newly diagnosed with OSA. Individuals with untreated OSA had significantly more days drinking in the last 30 days (M = 21.17 days, SD = 11.41) compared to no OSA/Treated OSA group (M = 8.82 days, SD = 10.92). There was no difference in change in PCL scores from baseline to post-treatment by the no-OSA/high compliance group and the low compliance group.

Conclusion
Taken together, OSA screening on the unit was accepted by the participants, feasible, and effective in diagnosing OSA. OSA screening and treatment should be considered as necessary on SUD and PTSD units. We did not find that OSA adherence predicted change in PTSD score, this is most likely due to veterans receiving their CPAP late into their stay on the unit. Future studies will need to examine OSA treatment on long term treatment outcomes.

Support: Support
This work is supported by UCSD Academic Senate Grant and a Veterans Affairs RR&D CDA (1lK2Rx002120-01) to Peter Colvonen.
0584 Detecting Sleep Disordered Breathing Using Sub-Terahertz Radio-Frequency Micro-Radar
Authors: Korotun M , Weizman L , Drori A , Zaccaria J , Goldstein T , Litman I , Hahn S , Greenberg H 
Published: May 2020

Abstract

Introduction
New sensor technologies are entering sleep testing at a rapid pace; Neteera™ developed a novel sensor and algorithm for sleep apnea detection utilizing a contact-free, radar-based sensor system. The system utilizes a high-frequency, low-power, directional micro-radar which operates at ~120GHz and a sampling rate of 2500Hz as well as algorithms which are able to detect both pulse and respiratory activity of subjects during sleep.

Methods
Adult subjects undergoing diagnostic PSG for clinical purposes were simultaneously assessed with the novel micro-radar system with sensors under the mattress. Disordered breathing events (DBEs) were scored from the PSG using AASM scoring guidelines and were compared with those detected by the micro-radar sensor. Test data were grouped into three sets: 1. Single under mattress sensor; 2. Two under mattress sensors on each side of the bed (to improve signal capture); 3. After software optimization. The micro-radar sensor detected DBEs but software to describe the type of DBEs (obstructive apnea/central apnea/hypopnea) is still under development. Detection rate of DBEs was compared between the two methodologies and the development sets.

Results
n=22 (12 F, 10 M), Age=50.8±12.4 years, BMI=35.32±7.37 kg/m2. Diagnostic PSG AHI: 19.7±29.4/hr, T90=15.8±25.7%. Percent DBEs missed by the micro-radar sensor: 1st set=14.6±10.6%; 2nd set=9.4±8.3%; 3rd set=1.2±2.6%. Number of DBEs assessed for each set was 646, 1144, 125 events, respectively. With each successive set, the detection rate improved.

Conclusion
A novel micro-radar, non-contact sensor technology can be used to detect DBEs during sleep. Detection rate improved with utilization of two sensors per bed and software optimization. Future software development is expected to improve detection rate and facilitate breathing event classification into obstructive apneas/central apneas/hypopneas.

Support
None.
0598 Blurred Binaries: The Clinical Management of Obstructive Sleep Apnea in Transgender Patients
Authors: Peters-Mathews B , Lee M , Sabzpoushan A 
Published: May 2020

Abstract

Introduction
Transgender patients require careful clinical assessment to identify the effects of hormones on their risk of obstructive sleep apnea. Testosterone increases sleep apnea risk and assigned males at birth may develop the condition earlier. Estrogen and progesterone are known to reduce sleep apnea risk. Depending on the use of supplemental hormones and surgical status, the risk of sleep apnea may be altered in a transgender patient. Comorbid conditions, including mood disorders and obesity, may further impact sleep. This topic has not been well-studied, and this pilot project identifies special needs that exist in transgender populations.

Methods
This retrospective chart review included 25 subjects who identify as transgender who have been managed at an urban sleep disorders center from 2017 to 2019. The case series was assessed to identify characteristics that impact the diagnosis and treatment of obstructive sleep apnea (natural and supplemental hormonal effects, surgical effects, comorbid conditions, etc.).

Results
The average age of the cohort was 34 years (range 16 to 76). Fourteen subjects were assigned females at birth and identify as men and 11 subjects were assigned males at birth and identify as women. Preferred pronoun usage was concordant with gender identity in 21 subjects, discordant in 1 subject, and gender-neutral (they/them) was used by 3 subjects. Based on 24 subjects, the average BMI was 35.5 (range 23.5 to 53.1). The measured neck circumference was &lt;16 inches in 9 subjects, &gt;17 inches in 6 subjects,and a risk factor for sleep apnea based on birth-assigned sex but not gender identity in 4 subjects. Hormone therapy was used by 24 subjects to enhance their gender identities. When documented, 6 subjects had mastectomies and 2 also had total hysterectomies. Anxiety or depression had been diagnosed in 20 subjects. Testing revealed sleep apnea in 18 subjects. Loss to follow up affected 9 subjects.

Conclusion
Transgender patients deserve respectful evaluation and careful consideration regarding risk factors for obstructive sleep apnea that may be impacted by gender-affirming hormonal therapy or surgery, and weight gain. Higher rates of mood disorders and loss to follow up may put these patients at long-term risk.

Support
N/A
0602 Daytime Sleepiness in Heart Failure with Preserved Versus Reduced Ejection Fraction
Authors: Schütz S G , Nguyen-Phan A , Konerman M , Hummel S , Chervin R D 
Published: May 2020

Abstract

Introduction
Sleep apnea is common in patients with heart failure, though often not associated with significant daytime sleepiness in heart failure with reduced ejection fraction (HFrEF). The clinical presentation of sleep apnea in patients who have heart failure with borderline or preserved ejections fraction (HFbEF and HFpEF, respectively) is not well characterized.

Methods
Eighty patients with heart failure were identified retrospectively in data from University of Michigan Sleep Disorders Laboratories. Heart failure was categorized as heart failure with reduced ejection fraction (HFrEF)/systolic heart failure, heart failure with borderline ejection fraction (HFbEF) or heart failure with preserved ejection fraction (HFpEF)/diastolic heart failure. Clinical information and Epworth Sleepiness Scale (ESS) scores were extracted from medical records. A subset of subjects underwent a diagnostic polysomnogram. ANOVA was used to compare clinical characteristics in subjects with different heart failure types.

Results
ESS scores trended higher in 49 subjects with HFpEF (ESS mean 10.9±4.7 [sd]) compared to 9 with HFbEF (ESS 8.0±3.4) and 22 with HFrEF (ESS 8.4±5.0) (p=0.058). Among the 40 subjects who underwent diagnostic polysomnography, no statistically significant difference emerged in apnea-hypopnea index between subjects with HFpEF, HFbEF, and HFrEF (p=0.43). No significant differences emerged for the central apnea index (p=0.16), despite magnitudes of discrepancy that suggested a larger sample size might show different

results
CAI in participants with HFrEF showed a mean of 9.0±14.6/h, compared to 0.1±0.1/h in HFbEF and 3.1±6.3/h in HFpEF.

Conclusion
Among these patients with HFpEF, HFbEF, and HFrEF, subjects with HFpEF showed a trend towards increased subjective daytime sleepiness, though overall apnea and central apnea severity did not differ between groups. Further examination of clinical phenotypes in larger cohorts may help guide care in heterogeneous heart failure populations.

Support
National Institutes of Health grant NS107158