Overnight Sleep Research Articles

P018 Effect of CBT-I on sleep-wake state discrepancy in individuals with co-morbid insomnia and sleep apnoea: A randomised controlled trial

Abstract Introduction Cognitive behavioural therapy for insomnia (CBT-I) is the recommended treatment for insomnia and improves insomnia symptoms. However, CBT-I effects on sleep-wake state discrepancy have not previously been examined in a sample of individuals with co-morbid insomnia and sleep apnoea (COMISA). This randomised controlled trial investigated the effect of CBT-I, versus no-treatment control, on sleep-wake state discrepancy in people with COMISA. Methods 145 participants had their subjective and objective sleep parameters recorded at pre- and post-treatment via overnight sleep diaries and polysomnography. Results Pre-treatment, individuals with COMISA significantly (p < 0.05) underestimated their sleep duration (M min = −51.9, SD = 94.1) and sleep efficiency (M % = −9.6, SD = 18.3) and significantly (p < 0.05) overestimated sleep onset latency (M min = 34.5, SD = 86.1). Post-treatment, there were significant reductions in sleep-wake state discrepancy parameters in both groups, but no significant interaction effects to support any differences between CBT-I versus waitlist control groups (all interactions, p > 0.367). Discussion These findings suggest that treating the insomnia aspect of COMISA through CBT-I first may not be an effective method of reducing sleep-wake state discrepancy. This is possibly due to sleep apnoea being untreated, contributing to frequent awakenings and the discrepancy between perceived and polysomnography derived sleep parameters. Future studies could involve a COMISA group that receives treatment for their sleep apnoea symptoms before CBT-I.

The effect of sleep and semantic information on associative novel word learning

ABSTRACT This study investigated the effect of overnight sleep on associative novel word learning and examined whether the effects of sleep on word learning are modulated by the provision of semantic information. Seventy-five healthy young adults attended an initial word-learning session followed by a delayed testing session. An interval of overnight sleep (sleep group) or daytime wakefulness (wake group) separated the two sessions. At the initial learning session, participants learned three-word names of 20 novel objects, where half the names comprised a novel word and two semantic attributes (semantic condition), and half comprised a novel word and two meaningless proper names (name condition). Novel word cued-recall was measured at both the initial and the delayed session. Although both groups demonstrated similar cued-recall accuracy at the first session, by the delayed session the sleep group demonstrated superior cued-recall accuracy compared to the wake group. There was no influence of semantics on the sleep-dependent consolidation of the novel words. Overall, these findings suggest that novel words encoded with or without the provision of semantic information can benefit from an overnight sleep period for consolidation.

Contributions of memory and brain development to the bioregulation of naps and nap transitions in early childhood

The transition from multiple sleep bouts each day to a single overnight sleep bout (i.e., nap transition) is a universal process in human development. Naps are important during infancy and early childhood as they enhance learning through memory consolidation. However, a normal part of development is the transition out of naps. Understanding nap transitions is essential in order to maximize early learning and promote positive long-term cognitive outcomes. Here, we propose a novel hypothesis regarding the cognitive, physiological, and neural changes that accompany nap transitions. Specifically, we posit that maturation of the hippocampal-dependent memory network results in more efficient memory storage, which reduces the buildup of homeostatic sleep pressure across the cortex (as reflected by slow-wave activity), and eventually, contributes to nap transitions. This hypothesis synthesizes evidence of bioregulatory mechanisms underlying nap transitions and sheds new light on an important window of change in development. This framework can be used to evaluate multiple untested predictions from the field of sleep science and ultimately, yield science-based guidelines and policies regarding napping in childcare and early education settings.

Do your troubles today seem further away than yesterday? On sleep's role in mitigating the blushing response to a reactivated embarrassing episode.

The "sleep to forget and sleep to remember hypothesis" proposes that sleep weakens the emotional tone of an experience while preserving or even enhancing its content. Prior experimental research however shows contradictory findings on how emotional reactivity changes after a period of sleep, likely explained by methodological variations. By addressing these inconsistencies, we investigated the mitigating effect of overnight sleep on emotional reactivity triggered by memory reactivation. Using a karaoke paradigm, we recorded participants' singing of two songs, followed by exposing them to one of the recordings (rec1) to induce an embarrassing episode. After a 12-hr period of either day-time wakefulness (N = 20) or including nighttime sleep (N = 20), we assessed emotional reactivity to the previously exposed recording (rec1) and the newly exposed recording (rec2). Emotional reactivity was assessed with a physiological measure of facial blushing as the main outcome and subjective ratings of embarrassment and valence. Sleep and wake were monitored with diaries and actigraphy. The embarrassing episode was successfully induced as indicated by objective and subjective measures. After controlling for an order effect in stimulus presentation, we found a reduction in blushing response to the reactivated recording (rec1) from pre- to post-sleep compared to wakefulness. However, emotional reactivity to the reactivated recording (rec1) and the new recording (rec2) did not differ after sleep and wakefulness. This study shows that facial blushing was reduced following overnight sleep, while subjective ratings were unaffected. Whether the beneficial effect of sleep is due to changes in memory representation or rather emotion regulation remains elusive.

Atrial Fibrillation Detection Based on a Residual CNN Using BCG Signals

Atrial fibrillation (AF) is the most common arrhythmia and can seriously threaten patient health. Research on AF detection carries important clinical significance. This manuscript proposes an AF detection method based on ballistocardiogram (BCG) signals collected by a noncontact sensor. We first constructed a BCG signal dataset consisting of 28,214 ten-second nonoverlapping segments collected from 45 inpatients during overnight sleep, including 9438 for AF, 9570 for sinus rhythm (SR), and 9206 for motion artifacts (MA). Then, we designed a residual convolutional neural network (CNN) for AF detection. The network has four modules, namely a downsampling convolutional module, a local feature learning module, a global feature learning module, and a classification module, and it extracts local and global features from BCG signals for AF detection. The model achieved precision, sensitivity, specificity, F1 score, and accuracy of 96.8%, 93.7%, 98.4%, 95.2%, and 96.8%, respectively. The results indicate that the AF detection method proposed in this manuscript could serve as a basis for long-term screening of AF at home based on BCG signal acquisition.

Evaluating the Typical Day-to-Day Variability of WHOOP-Derived Heart Rate Variability in Olympic Water Polo Athletes.

Heart rate (HR) and HR variability (HRV) can be used to infer readiness to perform exercise in athletic populations. Advancements in the photoplethysmography technology of wearable devices such as WHOOP allow for the frequent and convenient measurement of HR and HRV, and therefore enhanced application in athletes. However, it is important that the reliability of such technology is acceptable prior to its application in practical settings. Eleven elite male water polo players (age 28.8 ± 5.3 years [mean ± standard deviation]; height 190.3 ± 3.8 cm; body mass 95.0 ± 6.9 kg; international matches 117.9 ± 92.1) collected their HR and HRV daily via a WHOOP strap (WHOOP 3.0, CB Rank, Boston, MA, USA) over 16 weeks ahead of the 2021 Tokyo Olympic Games. The WHOOP strap quantified HR and HRV via wrist-based photoplethysmography during overnight sleep periods. The weekly (i.e., 7-day) coefficient of variation in lnRMSSD (lnRMSSDCV) and HR (HRCV) was calculated as a measure of day-to-day variability in lnRMSSD and HR, and presented as a mean of the entire recording period. The mean weekly lnRMSSDCV and HRCV over the 16-week period was 5.4 ± 0.7% (mean ± 95% confidence intervals) and 7.6 ± 1.3%, respectively. The day-to-day variability in WHOOP-derived lnRMSSD and HR is within or below the range of day-to-day variability in alternative lnRMSSD (~3–13%) and HR (~10–11%) assessment protocols, indicating that the assessment of HR and HRV by WHOOP does not introduce any more variability than that which is naturally present in these variables.

A Real-World Study on the Day and Night-Time Symptoms Among Greek COPD Patients Who Recently Initiated Treatment with Dual Bronchodilation: The DANICO Study.

PurposeThe rationale of this study was to investigate the prevalence of daily and night symptoms and quality of sleep in Greek COPD patients as a means to evaluate their response to treatment with the fixed dose combination of aclidinium/formoterol (administered through the Genuair® device).Patients and MethodsThis study was a multicenter, nationwide, non-interventional, observational study in 2105 patients suffering from COPD, who have recently started treatment with aclidinium/formoterol. Patients were attending to two visits, one baseline and a final visit, 3 months later. Different variables have been collected on either the baseline or the final visit or both: demographics, vital sign measurements, COPD-related medical history parameters, comorbidities, COPD assessment test (CAT), COPD severity based on spirometry measurements, COPD stage based on the ABCD assessment approach proposed by the 2019 Global Initiative for Chronic Obstructive Lung Disease (GOLD), COPD treatment report, and severity of early-morning, daytime and night-time COPD-related symptoms. Reasons for prescribing aclidinium/formoterol, satisfaction of patients to the treatment, as well as their compliance have also been recorded.ResultsAfter 3 months on aclidinium/formoterol, 50.1% of the patients experienced an improvement in their early-morning symptoms. Furthermore, 49.9% of them experienced an improvement in their daily symptoms, 44.9% improved their night-time symptoms and 43.2% reduced the frequency of overnight sleep disruptions due to COPD symptoms. These favorable outcomes apply mainly to GOLD Groups B–D. Treatment with aclidinium/formoterol improved on average the pre-bronchodilation FEV1% pred by 3.18%, the post-bronchodilation FEV1% pred by 2.78% and reduced CAT score by 5.22 points. Satisfaction with using aclidinium/formoterol across patients was high, as well as compliance to therapy.ConclusionAclidinium/formoterol provided significant benefits on the quality of life of COPD patients by reducing the morning, daytime and the night-time symptoms and symptom burden in GOLD Groups B–D, and activity impairment under real-life conditions in all GOLD ABCD groups.

Sleep deprivation and recovery sleep affect healthy male resident’s pain sensitivity and oxidative stress markers: The medial prefrontal cortex may play a role in sleep deprivation model

Sleep is essential for the body’s repair and recovery, including supplementation with antioxidants to maintain the balance of the body’s redox state. Changes in sleep patterns have been reported to alter this repair function, leading to changes in disease susceptibility or behavior. Here, we recruited healthy male physicians and measured the extent of the effect of overnight sleep deprivation (SD) and recovery sleep (RS) on nociceptive thresholds and systemic (plasma-derived) redox metabolism, namely, the major antioxidants glutathione (GSH), catalase (CAT), malondialdehyde (MDA), and superoxide dismutase (SOD). Twenty subjects underwent morning measurements before and after overnight total SD and RS. We found that one night of SD can lead to increased nociceptive hypersensitivity and the pain scores of the Numerical Rating Scale (NRS) and that one night of RS can reverse this change. Pre- and post-SD biochemical assays showed an increase in MDA levels and CAT activity and a decrease in GSH levels and SOD activity after overnight SD. Biochemical assays before and after RS showed a partial recovery of MDA levels and a basic recovery of CAT activity to baseline levels. An animal study showed that SD can cause a significant decrease in the paw withdrawal threshold and paw withdrawal latency in rats, and after 4 days of unrestricted sleep, pain thresholds can be restored to normal. We performed proteomics in the rat medial prefrontal cortex (mPFC) and showed that 37 proteins were significantly altered after 6 days of SD. Current findings showed that SD causes nociceptive hyperalgesia and oxidative stress, and RS can restore pain thresholds and repair oxidative stress damage in the body. However, one night of RS is not enough for repairing oxidative stress damage in the human body.

Respiratory analysis during sleep using a chest-worn accelerometer: A machine learning approach

Objective:There is a great interest in observing breathing patterns during sleep, as sleep disturbances can be caused by respiratory irregularity and cessations. In this paper, we introduce the first steps to an accelerometer-based screening tool for respiratory rate estimation and a novel approach towards detecting breathing cessations such as apnea/hypopnea, by extending and combining established signal processing routines with machine learning. Methods:From a single chest-worn accelerometer, we estimate the respiratory rate based on the inhalation/exhalation movements of the chest and carry out a full overnight validation. On this basis, we build a set of features customized to detect irregular respiratory activity, including a novel feature: the respiratory peak variance (RPV). From thirteen healthy subjects, a classification model was trained, validated, and tested with over 98 h of PSG-labeled accelerometer data. Results:The algorithm estimated the respiratory rate with a mean difference of 1.8 breaths per minute compared to respiratory inductance plethysmography during overnight PSGs. The machine learning classifier detected respiratory cessations with a sensitivity and specificity of 76.05% and 70.05% respectively, with an overall accuracy of 70.95%. Conclusion:We successfully demonstrated the potential of a novel respiratory feature set in a preliminary application with young healthy volunteers for respiratory rate estimation and in identifying apnea/hypopnea events during overnight sleep. Significance:We present a simple and unobtrusive wearable system that can serve as a home screening tool for sleep-related breathing disorders.

Rapid eye movement sleep in adolescent females with borderline personality disorder

Objective: The aim of the study was detecting Rapid Eye Movement (REM) sleep abnormalities in adolescent females with borderline personality disorder (BPD). Method: A case control study included a convenient sample of 30 adolescent females with BPD compared to 30 matched healthy controls. Pittsburgh Sleep Quality Index and an overnight sleep lab polysomnographic study were applied to both groups to assess sleep. Results: Patients with BPD were subjectively dissatisfied with the quality of sleep compared to controls (p<0.001). Abnormalities in REM sleep in patients when compared to controls were higher REM percent (p=0.001), shorter REM latency (p=0.001), higher REM density (p=0.001) and higher number of REM periods in the first half of the night (p=0.000). Conclusion: REM sleep abnormalities are found in adolescent patients with BPD, which may be considered as trait markers for BPD.

Morning perception of sleep, stress and mood, and its relationship with overnight physiological sleep processes in adolescents

Morning perception of sleep, stress and mood, and its relationship with overnight physiological sleep processes in adolescents

A brief nap during an acute stressor improves negative affect.

Overnight sleep can reduce perceived stress, and improve associated cognitive disruptions and negative affect after an acute stressor. Whether a brief nap can also bestow these benefits in a non-sleep-restricted population is currently unknown. In this study that used a between-subjects design, stress was triggered by administering a modified Trier Social Stress Test to two groups of participants (nap [n=29], wake [n=41]). All participants were instructed they would give a speech during the study but the topic would be withheld until later, and then completed a math task. After a 40-min break in which participants watched a neutral video or took a nap monitored with electroencephalography, stress was reinforced by presenting the speech topics and giving participants a 10-min preparation period. Next, instead of giving a speech, the study ended and participants were debriefed. Negative affect, perceived stress and working memory were measured at multiple time points before and after the break. Both groups showed lower perceived stress and improved working memory after the break than before, but a nap did not confer additional benefits for perceived stress or working memory beyond taking a break. However, the nap group exhibited lower negative affect after the break than the wake group, and only the nap group showed a reduction in negative affect compared with initial negative affect levels. These results indicate a nap can improve negative emotions accompanying a stressor to a greater extent than taking a break, and suggest that brief naps may be a useful way to improve mood while experiencing an acute stressor.

Overnight sleeping heart rate variability of Army recruits during a 12-week basic military training course

PurposeThis study aimed to quantify sleeping heart rate (HR) and HR variability (HRV) alongside circulating tumor necrosis factor alpha (TNFα) concentrations during 12-week Basic Military Training (BMT). We hypothesised that, despite a high allostatic load, BMT would increase cardiorespiratory fitness and HRV, while lowering both sleeping HR and TNFα in young healthy recruits.MethodsSixty-three recruits (18–43 years) undertook ≥ 2 overnight cardiac frequency recordings in weeks 1, 8 and 12 of BMT with 4 h of beat-to-beat HR collected between 00:00 and 06:00 h on each night. Beat-to-beat data were used to derive HR and HRV metrics which were analysed as weekly averages (totalling 8 h). A fasted morning blood sample was collected in the equivalent weeks for the measurement of circulating TNFα concentrations and predicted VO2max was assessed in weeks 2 and 8.ResultsPredicted VO2max was significantly increased at week 8 (+ 3.3 ± 2.6 mL kg−1 min−1; p < 0.001). Sleeping HR (wk1, 63 ± 7 b min−1) was progressively reduced throughout BMT (wk8, 58 ± 6; wk12, 55 ± 6 b min−1; p < 0.01). Sleeping HRV reflected by the root mean square of successive differences (RMSSD; wk1, 86 ± 50 ms) was progressively increased (wk8, 98 ± 50; wk12, 106 ± 52 ms; p < 0.01). Fasted circulating TNFα (wk1, 9.1 ± 2.8 pg/mL) remained unchanged at wk8 (8.9 ± 2.5 pg/mL; p = 0.79) but were significantly reduced at wk12 (8.0 ± 2.4 pg/mL; p < 0.01).ConclusionIncreased predicted VO2max, HRV and reduced HR during overnight sleep are reflective of typical cardiorespiratory endurance training responses. These results indicate that recruits are achieving cardiovascular health benefits despite the high allostatic load associated with the 12-week BMT.

Sleep bolsters schematically incongruent memories.

Our ability to recall memories is improved when sleep follows learning, suggesting that sleep facilitates memory consolidation. A number of factors are thought to influence the impact of sleep on newly learned information, such as whether or not we rehearse that information (e.g. via restudy or retrieval practice), or the extent to which the information is consistent with our pre-existing schematic knowledge. In this pre-registered, online study, we examined the effects of both rehearsal and schematic congruency on overnight consolidation. Participants learned noun-colour pairings (e.g. elephant-red) and rated each pairing as plausible or implausible before completing a baseline memory assessment. Afterwards, participants engaged in a period of restudy or retrieval practice for the pairings, and then entered a 12 h retention interval of overnight sleep or daytime wakefulness. Follow-up assessments were completed immediately after sleep or wake, and again 24 h after learning. Our data indicated that overnight consolidation was amplified for restudied relative to retested noun-colour pairings, but only when sleep occurred soon after learning. Furthermore, whereas plausible (i.e. schematically congruent) pairings were generally better remembered than implausible (i.e. schematically incongruent) pairings, the benefits of sleep were stronger for implausible relative to plausible memories. These findings challenge the notion that schema-conformant memories are preferentially strengthened during post-learning sleep.

Getting on the Same Page: A Quality Improvement Project to Enhance Nurse-to-Resident Communications and Reduce Overnight Sleep Interruptions.

Many residency programs utilize "home call" residents who answer hospital communications and place orders from home. Often, residents are required to live nearby and arrive in-person if needed. Residents work normal daytime work hours while on home call, which can last several nights. This disrupts sleep and creates the potential for increased resident fatigue and patient safety issues. To implement and evaluate a novel program to reduce non-urgent overnight pages from nurses to home call physical medicine and rehabilitation (PM&R) residents between 11 pm and 6 am. At an inpatient acute rehabilitation unit in a tertiary care university teaching hospital, we implemented a 2-step prospective quality improvement study with interventions derived from nurse-physician meetings implemented 9 months apart in 2018 and 2019. The first intervention was a centralized nightly handoff sheet. The second intervention was to display suggested PRN medication lists in resident workrooms. The primary outcome measure was the percentage of nights with non-urgent pages between 11 pm and 6 am. Tracking urgent pages and 7-10 am emergent pages were used as balancing measures. A total of 1835 text-based nursing pages (366 pre- and 1469 post-intervention) were received and categorized by content, urgency, and timing over a 17-month period. Post-intervention, there was a stable 25% decrease in nighttime non-urgent pages. The most common hour to be paged shifted from 11 pm to 8 pm. Pain, constipation, insomnia, and nausea were the most common complaints overnight. By characterizing and studying nighttime pages, residents collaborated with nighttime nursing staff through structured meetings to reduce non-urgent nighttime pages for more than 1 year.

The impact of sleep disordered breathing on cardiac troponin in acutely decompensated heart failure

PurposeSleep disordered breathing in decompensated heart failure has physiological consequences (e.g., intermittent hypoxemia) that may predispose to subclinical myocardial injury, yet a temporal relationship between sleep apnea and troponin elevation has not been established.MethodsWe assessed the feasibility of performing respiratory polygraphy and measuring overnight high-sensitivity cardiac troponin T change in adults admitted to the hospital with acutely decompensated heart failure. Repeat sleep apnea tests (SATs) were performed to determine response to optimal medical heart failure therapy. Multivariable logistic regression was used to identify associations between absolute overnight troponin change and sleep apnea characteristics.ResultsAmong the 19 subjects with acutely decompensated heart failure, 92% of SATs demonstrated sleep disordered breathing (apnea–hypopnea index [AHI] > 5 events/h). For those with repeat SATs, AHI increased in 67% despite medical management of heart failure. Overnight troponin increase was associated with moderate to severe sleep apnea (vs. no to mild sleep apnea, odds ratio (OR = 18.4 [1.51–224.18]), central apnea index (OR = 1.11 [1.01–1.22]), and predominantly central sleep apnea (vs. obstructive, OR = 22.9 [1.29–406.32]).ConclusionsSleep apnea severity and a central apnea pattern may be associated with myocardial injury. Respiratory polygraphy with serial biomarker assessment is feasible in this population, and combining this approach with interventions (e.g., positive airway pressure) may help establish if a link exists between sleep apnea and subclinical myocardial injury.

0110 Nap-Related Change in Memory Precision may be Related to Slow-Wave Sleep in Early Childhood

Abstract Introduction In early childhood (3-5 years), naps comprise part of children’s 24-hr sleep. Naps support some types of learning (declarative, emotional), enhancing children’s ability to correctly identify previously seen items. During this time, children’s ability to form precise memories also improves, likely due to ongoing hippocampal development and maturation of processes allowing for pattern separation. Whether naps support the ability to form precise memory representations, allowing children to discriminate between previously seen vs. similar but novel items, is unclear. Here, we used a mnemonic similarity task to examine whether daytime naps support children’s recall of specific images more so than a period of wake. Further, we tested whether this nap-related improvement persists across overnight sleep. We hypothesized that task improvement would be associated with slow-wave sleep (SWS), as this stage has been shown to support episodic memory in preschool-aged children. Methods Participants (N=7, 4 females, Mage=56.1 mos) encoded items in the morning, verbally categorizing each image as something they would find “inside” or “outside”. They recalled items at three time points: immediately following encoding, after their nap/wake period, and the following morning after overnight sleep. Recall involved being shown a single image and responding whether it had been previously seen or not. Recall items included targets, foils, and lures. PSG was recorded during the nap and overnight sleep bouts. Results When controlling for age, children forgot fewer target items following a nap than a comparable period of wake (p=.05). Following a nap and overnight sleep, children also exhibited marginally less forgetting of target items than following a period of wake and overnight sleep (p=.102). Lure discrimination index (LDI; false alarm lures minus false alarm foils) did not differ between nap and wake conditions. Change in target recall following the nap was associated with SWS% during the nap (r=.96, p=.01), but not nap duration (p=.27). Conclusion Napping supported children’s ability to recall target items, but not to correctly reject lures, suggesting naps’ benefit towards more generalized memory. Nap SWS% was associated with less forgetting of target items, supporting its role in hippocampal-dependent memory consolidation. Analyses of overnight sleep data and inclusion of more participants may help better elucidate the relationship between preschool children’s sleep and memory development. Support (If Any) NSF BCS 1749280 NIH R21 HD094758 NIH R01 HL111695

0007 Temporal Associations Between Actigraphy-Measured Daytime Movement Behaviors and Daytime Sleep in Early Childhood

Abstract Introduction Although napping in early childhood is associated with some cognitive and behavioral outcomes, less is known about relations with physical health measures. Lower levels of sedentary behavior and higher levels of physical activity have been beneficially associated with sleep measures in adults. Studies exploring sleep and daytime movement behaviors (sedentary time and physical activity) in young children have had inconsistent results and primarily focused on overnight sleep. The purpose of this micro-longitudinal analysis was to determine if: 1) daytime movement behaviors predicted the likelihood of napping the next day, 2) daytime movement behaviors predicted next-day nap duration, and 3) the occurrence of a nap predicted next-day movement behaviors. Methods In 240 children (age=50.8±9.8 months, 49.2% female) sedentary time (% of wake time), total physical activity (counts/min), and nap duration (min) were derived from wrist-based actigraphy (mean = 9.7 days), and occurrence of a nap was recorded daily. Multilevel logistic and linear models with lagged effects were used to examine temporal within-person relations between wake behaviors and nap sleep, and adjusted for night’s sleep duration of nights between days of interest (min), age (months), sex (male or female), and socioeconomic status (index). Preliminary models included interactions with nap habituality (rarely, sometimes, or frequent). Results Occurrence of a nap was not associated with next-day wake behaviors and previous-day wake behaviors did not predict nap duration. However, on days children napped, they were less sedentary (B=-2.09, p&amp;lt;0.001) and more active (B=25.8, p&amp;lt;0.001) the following day. Nap habituality did not moderate these associations. Conclusion Bidirectional associations between nap sleep and daytime wake behaviors were not evident. While daytime movement behaviors were not predictive of nap sleep, napping was beneficially associated with subsequent-day movement behaviors in preschool children. Further studies could explore specific nap sleep metrics in samples with more diverse sleep health, as well as consider the reason for daytime napping. Support (If Any) NIH R01 HL111695

Berlin and Epworth Surveys to Predict Obstructive Sleep Apnea for Adults on Biomimetic Oral Appliance Therapy: A Nonrandomized Clinical Trial.

Background Two questionnaires (Berlin Questionnaire (BQ) and Epworth Sleepiness Scale (ESS)) are the widely used screening instruments for subjects suffering from sleep disorders. Obstructive sleep apnea (OSA) is the most common form of sleep-disordered breathing. The biomimetic oral appliance therapy (BOAT) offers an alternative nonsurgical method, which can improve symptoms and indices of OSA on objective sleep testing. Aim To describe testing the ability of BQ and EES for prediction of BOAT outcomes during OSA. Methods Seventeen adults (9 males, 8 females; age, mean (SD): 45.76 (10.31), BMI mean (SD): 33.5(13.43)) who underwent an overnight sleep study were diagnosed by a sleep specialist physician. The BQ and EES were recorded before and after BOAT treatment. Subjects with mild-to-moderate OSA had 2 months of follow-up visits and underwent a final overnight sleep study to measure apnea-hypopnea index (AHI). The subjects were asked to wear the appliance for 10–12 hours/day and at night. Findings were analyzed statistically using paired t-tests. Result As per sleep test results, pre-BOAT AHI measures versus post-BOAT AHI measures showed significant improvement. Comparing the BQ before versus after treatment showed that at the pretreatment stage, 66.0% of patients had high-risk score, whereas 34% had low-risk score. After treatment, 66.0% of patient had low-risk scores, whereas 34% had high-risk scores. As for the ESS, treatment resulted in significant reduction of total score from 10.43 ± 6.32 to 5.00 ± 5.20 (P < 0.01, paired t-test). Finally, there was a mild negative correlation between AHI and each of the BQ and ESS scores that was not statistically significant (r = −0.420, N = 26, P > 0.05, and r = −0.41, N = 26, P > 0.05, respectively). Conclusion The BOAT device may provide a useful form of therapy to improve OSA-related PSG parameters such as AHI. Both BQ and ESS were predictive to improvements detected by the sleep study during BOAT device use.

Waist-hip ratio is an independent predictor of moderate-to-severe OSA in nonobese males: a cross-sectional study

BackgroundAdiposity is a well-established risk factor for obstructive sleep apnea (OSA), but whether a combination of preferable anthropometric measurements may improve the accuracy of detecting OSA is unknown. This study aimed to explore the accuracies of the waist-hip ratio (WHR) in conjunction with the body mass index (BMI) when identifying the severity of OSA.DesignA total of 2012 participants in the China-Japan Friendship Hospital from January 2018 to December 2019 underwent anthropometric measurements and an overnight home sleep test (HST). The 244 subjects who met the criteria for obstructive sleep apnea (apnea–hypopnea index (AHI) ≥ 5 events/hour) were divided into four groups: Group A (55 patients with WHR ≥ 0.9 and BMI ≥ 28 kg/m2); Group B (12 patients with WHR < 0.9 and BMI ≥ 28 kg/m2); Group C (69 patients with WHR ≥ 0.9 and BMI < 28 kg/m2); and group D (108 patients with WHR < 0.9 and BMI < 28 kg/m2).ResultsThe AHI, apnea index (AI), hypopnea index (HI), and oxygen desaturation index (ODI) were significantly different among the 4 groups (p < 0.05). The WHR was positively correlated with AHI (r = 0.22, p < 0.001), AI (r = 0.270, p = 0.004), and ODI (r = 0.286, p = 0.0022) and negatively correlated with lowest oxygen pulse saturation (LSpO2) (r = 0.246, p = 0.008) only in nonobese patients. Moreover, the WHR was found to be a screening marker for moderate-to-severe OSA in Group D (p < 0.05). When used to identify severe OSA in Group D, the WHR cut-off point of 0.873 yielded a sensitivity of 65% and specificity of 56% (p < 0.05).ConclusionIn nonobese male OSA patients, WHR is a moderate screening marker for moderate-to-severe OSA and an independent risk factor for OSA severity.