Sleep Onset Research Articles

Research progress on the first‐night effect in polysomnography studies

AbstractThe first‐night effect (FNE) is a prevalent occurrence in sleep monitoring that can impact the accuracy of monitoring results, encompassing both FNE and reverse first‐night effect. FNE is characterized by extended sleep onset latency, reduced total sleep time, diminished sleep efficiency, prolonged wake‐time after sleep onset, among other manifestations. The physiological and psychological mechanisms underlying FNE are primarily linked to acute stress induced by the environment and heightened levels of anxiety, involving the default mode network. FNE exhibits varying manifestations and impacts across individuals of different age groups and genetic predispositions. We also discuss the influence of placebo and sedative‐hypnotics on FNE. Understanding these factors is crucial for guiding clinicians and technologists in standardizing polysomnography (PSG) practices and improving the accuracy of sleep disorder diagnoses.

Cognitive benefits of sleep: a narrative review to explore the relevance of glucose regulation

Abstract Sleep is essential for maintaining optimal health. Both sleep duration and quality have been linked to various physiological functions and physical and mental health outcomes. Nutrition has been shown to impact sleep parameters, from the nutrient composition of foods, such as tryptophan levels, to the physiological response to foods, such as the glucose response. However, the relationship between glycemic control and sleep, and its impact on next day benefits, particularly on cognitive performance, remains complex and is not fully understood. This narrative review aims to explore the relationship between glycemia and sleep, and how it may affect cognitive performance the following day. The review includes data from observational and interventional studies, discussing mechanisms of action that may explain the modulating effect of glycemia on sleep and cognition. The evidence suggests that lower postprandial glucose and low variation of nocturnal glucose are associated with better sleep quality and shorter sleep onset latency. Good sleep quality, in turn, is positively associated with cognitive processes such as sustained attention and memory consolidation measured the next day after sleep. Future research opportunities lie in investigating the effects of modulating the glycemic and insulinemic responses through evening meals on sleep quality and next-day cognitive performance. Well-designed clinical trials involving healthy individuals are necessary to establish the effects of these interventions. Controlling glycemic and insulinemic profiles through the evening meal may have significant implications for improving sleep quality and cognitive performance, with potential impact on individual mental health, productivity, and overall well-being.

Exploring the relation between REM sleep behavior disorder onset and striatal dopaminergic dysfunction in Parkinson's Disease.

The α-Synuclein Origin and Connectome (SOC) model recently proposed two different Parkinson's Disease (PD) phenotypes clinically based on the relationship between REM sleep behavior disorder (RBD) and motor symptoms' onset: a "body first" phenotype and a "brain first" phenotype in which RBD precedes or may follow the motor onset, respectively. A higher burden of non-motor symptoms as well as a more symmetrical clinical presentation have also been predicted in the body-first phenotype. This point has been poorly assessed through semi-quantitative striatal dopaminergic functional imaging to date. To explore the relation between RBD onset and striatal dysfunction in PD. PD patients were retrospectively enrolled and clinical follow-up data were gathered. Presence and onset of probable RBD were evaluated classifying patients into PD-RBDpre (onset before motor symptoms), PD-RBDpost (onset after motor symptoms) and PD-RBD-. Semi-quantitative 123I-FP-CIT-DAT-SPECT imaging was performed at baseline. Mean putamen and caudate-specific binding ratios (SBR) and asymmetry index (AI) were computed. Fifty-six PD patients were enrolled (10 PD-RBDpre, 19 PD-RBDpost and 27 PD-RBD-). A more symmetrical motor impairment, higher mild cognitive impairment (MCI) prevalence, lower caudate SBR and lower putamen AI were found in PD-RBDpre. A negative trend in MCI prevalence as well as a positive trend in both caudate SBR and putamen AI were found across PD-RBDpre, PD-RBDpost and PD-RBD-. Different patterns of striatal dopaminergic dysfunction and cognitive impairment based on RBD onset were unraveled, supporting the SOC model's predictions.

Age-related characteristics of sedation in pediatric patients and their correlated adverse events: a cohort study

ObjectiveThe objective of this research was to examine the features and potential hazards of sedation in children of varying ages. Additionally, the study aimed to comprehend these variations to enhance the safety and efficacy of clinical applications.MethodsA retrospective analysis was conducted on case data involving pediatric patients who underwent imaging procedures in outpatient settings and necessitated procedural sedation from 2022 to 2024. The research participants were categorized into three age groups: ≤1 year, 1–3 years, and 3–12 years. The primary sedative agents administered were oral midazolam in conjunction with intranasal dexmedetomidine. We examined the effects of sedation and the occurrence of adverse events across various age groups. Additionally, we applied multivariate logistic regression to identify factors linked to these adverse events.ResultsThe study observed 2,194 children, with 879 (40.1%) being ≤1-year-old. The ≤1-year-old group achieved faster sleep onset at 18.7 ± 0.3 min, with no significant variance in awakening time and length of stay among the groups. The incidence of adverse events varied significantly by age, with the highest rate of 12.2% in the ≤1-year-old group and the lowest rate of 9.7% in the 3–12-year-old group. Multivariate analysis revealed age as an independent factor affecting adverse event occurrence, with a relative risk ratio (AOR) of 2.21 (95% CI: 1.31–3.75) for delayed awakening in children ≤1-year-old, 15.03 (95% CI: 1.92–117.61) for hypoglycemia, and a relative risk ratio (AOR) of 4.58 (95% CI: 2.22–9.42) for receiving a significant intervention.ConclusionsSignificant variations in sedation reactions and adverse events were observed across the different age groups. Specifically, children aged ≤1 year exhibited a higher susceptibility to adverse events such as delayed awakening and hypoglycemia. Clinical Trial Registrationchictr.org.cn identifier (ChiCTR2400082774).

Anhedonia Links Sleep Problems and Suicidal Thoughts: An Intensive Longitudinal Study in High-Risk Adolescents.

Growing research indicates that sleep problems are a robust independent risk factor for suicidal thoughts and behaviors among youth. However, relatively little is known about how this risk is conferred. This study used an intensive longitudinal design to investigate anhedonia as a mechanism linking sleep problems and next-day suicidal thoughts in a clinically high-risk sample of adolescents. Adolescents (N = 48; Mage=14.96; 77.1% white, 64.6% female) completed an ecological momentary assessment (EMA) study design for 28 days following discharge from acute psychiatric care for suicide risk. Daily sleep diaries were used to assess prior night total sleep time and sleep onset latency. Ecological momentary assessment was used to assess anhedonia and suicidal thoughts up to six times per day. A series of multi-level structural equation models were used to examine facets of anhedonia as parallel mediators of the association between sleep problems and next-day suicidal thoughts. Significant direct effects were found between sleep problems and consummatory anhedonia, consummatory anhedonia and suicidal thoughts, and anticipatory anhedonia and suicidal thoughts. There were significant indirect (mediated) effects between sleep problems and next-day suicidal thoughts through consummatory anhedonia, but not anticipatory anhedonia. Findings provide initial evidence as to how sleep problems may confer risk for next-day suicidal thoughts- by increasing consummatory anhedonia. Future research is needed to replicate these findings in larger samples and investigate how modifying anhedonia may mitigate suicide risk in youth.

Domain Adversarial Convolutional Neural Network Improves the Accuracy and Generalizability of Wearable Sleep Assessment Technology

Wearable accelerometers are widely used as an ecologically valid and scalable solution for long-term at-home sleep monitoring in both clinical research and care. In this study, we applied a deep learning domain adversarial convolutional neural network (DACNN) model to this task and demonstrated that this new model outperformed existing sleep algorithms in classifying sleep–wake and estimating sleep outcomes based on wrist-worn accelerometry. This model generalized well to another dataset based on different wearable devices and activity counts, achieving an accuracy of 80.1% (sensitivity 84% and specificity 58%). Compared to commonly used sleep algorithms, this model resulted in the smallest error in wake after sleep onset (MAE of 48.7, Cole–Kripke of 86.2, Sadeh of 108.2, z-angle of 57.5) and sleep efficiency (MAE of 11.8, Cole–Kripke of 18.4, Sadeh of 23.3, z-angle of 9.3) outcomes. Despite being around for many years, accelerometer-alone devices continue to be useful due to their low cost, long battery life, and ease of use. Improving the accuracy and generalizability of sleep algorithms for accelerometer wrist devices is of utmost importance. We here demonstrated that domain adversarial convolutional neural networks can improve the overall accuracy, especially the specificity, of sleep–wake classification using wrist-worn accelerometer data, substantiating its use as a scalable and valid approach for sleep outcome assessment in real life.

Objective sleep monitoring at home in older adults: A scoping review.

Inadequate sleep in older adults is linked to health issues such as frailty, cognitive impairment and cardiovascular disorders. Maintaining regular sleep patterns is important for healthy aging, making effective sleep monitoring essential. While polysomnography is the gold-standard for diagnosing sleep disorders, its regular use in home settings is limited. Alternative objective monitoring methods in the home can offer insights into natural sleep patterns and factors affecting them without the limitations of polysomnography. This scoping review aims to examine current technologies, sensors and sleep parameters used for home-based sleep monitoring in older adults. It also aims to explore various predictors and outcomes associated with sleep to understand the factors of sleep monitoring at home. We identified 54 relevant articles using PubMed, Scopus, Web of Science and an AI tool (Research Rabbit), with 48 studies using wearable technologies and eight studies using non-wearable technologies. Further, six types of sensors were utilized. The most common technology employed was actigraphy wearables, while ballistocardiography and electroencephalography were less common. The most frequent objective parameters of sleep measured were total sleep time, wakeup after sleep onset and sleep efficiency, with only six studies evaluating sleep architecture in terms of sleep stages. Additionally, six categories of predictors and outcomes associated with sleep were analysed, including Health-related, Environmental, Interventional, Behavioural, Time and Place, and Social associations. These associations correlate with total sleep time, wakeup after sleep onset and sleep efficiency, and include in-bed behaviours, exterior housing conditions, aerobic exercise, living place, relationship status, and seasonal thermal environments.

Sleep and Depressive Symptoms in Sedentary Community-Dwelling Older Adults With Sleep Complaints: Findings From Ambulatory Sleep EEG.

There is limited and inconsistent evidence on the association between electroencephalography (EEG) measured sleep and depressive symptoms among community-dwelling older adults. This study aimed to investigate the cross-sectional association between EEG-measured sleep and depressive symptoms. Using baseline data from a randomized clinical trial, we included 66 sedentary community-dwelling older adults with sleep complaints (≥ 1 self-reported insomnia symptom). Sleep was measured using an in-home sleep EEG (Sleep Profiler™) for 2 nights and the Geriatric Depression Scale (GDS-15) was used to measure depressive symptoms. Multiple linear regression analyses were conducted with each sleep parameter as the primary predictor and GDS score as the outcome, adjusting for age, sex, race, education, marital status, chronic conditions, and Montreal Cognitive Assessment (MoCA) score. Several sleep variables were associated with depressive symptoms (GDS score), including a higher percentage of sleep stage N1 (B = 0.11, 95% confidence interval [CI]: 0.02 - 0.20) and N2 (B = 0.04, 95% CI: 0.00 - 0.08), a lower percentage of N3 sleep (B = -0.04, 95% CI: -0.08 to -0.01), greater wake after sleep onset (B = 0.01, 95% CI: 0.00 - 0.02), and a greater number of awakenings ≥90s/hour (B = 0.87, 95% CI: 0.21-1.53). Our study reveals that among sedentary community-dwelling older adults with sleep complaints, more lighter sleep (stage N1, N2), less deep (N3) sleep, and increased awakenings are associated with more depressive symptoms. Sleep interventions aimed at enhancing sleep architecture may also help alleviate depressive symptoms in this population.

Significant nocturnal wakefulness after sleep onset in metabolic dysfunction-associated steatotic liver disease.

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a multisystemic disease with a multifactorial pathogenesis involving dietary, environmental, and genetic factors. Previous mouse models suggested that circadian misalignment may additionally influence its development as it influences metabolism in diverse organs including the liver. Further, data from sleep questionnaires proved sleep-wake disruption in patients with MASLD. We objectively assessed sleep-wake rhythms in patients with biopsy-proven MASLD (n = 35) and healthy controls (HC, n = 16) using actigraphy 24/7 for 4weeks. With the aim to re-align sleep rhythms a single standardized sleep hygiene education session was performed after 2weeks. Actigraphy data revealed that MASLD patients had more awakenings per night (MASLD vs. HC 8.5 vs. 5.5, p = 0.0036), longer wakefulness after sleep onset (MASLD vs. HC 45.4min vs. 21.3min, p = 0.0004), and decreased sleep efficiency (MASLD vs. HC 86.5% vs. 92.8%, p = 0.0008) compared with HC despite comparable sleep duration. Patients with MASLD self-reported shorter sleep duration (MASLD vs. HC 6h vs. 6h 45min, p = 0.01) and prolonged sleep latency contributing to poorer sleep quality. Standardized sleep hygiene education did not produce significant changes in sleep parameters. Our findings indicate fragmented nocturnal sleep in patients with MASLD, characterized by increased wakefulness and reduced sleep efficiency, perceived subjectively as shortened sleep duration and delayed onset. A single sleep hygiene education session did not improve sleep parameters.

Efficacy and safety of lemborexant in subjects with insomnia disorder receiving medications for depression or anxiety symptoms.

Individuals with insomnia frequently have comorbid depression or anxiety. This study sought to provide a preliminary indication of the effects of lemborexant (LEM) in subjects treated for mild depression/anxiety symptoms. E2006-G000-303 (NCT02952820; EudraCT 2015-001463-39; SUNRISE-2) was a 12-month, phase 3, randomized, placebo-controlled, double-blind study where subjects with insomnia disorder were randomized (1:1:1) to placebo, LEM 5 mg (LEM5), or LEM 10 mg (LEM10) for 6 months. During the second 6 months (not reported), placebo-treated subjects were re-randomized to LEM5 or LEM10. In this post hoc analysis, changes from baseline (CFB) in subject-reported (subjective) sleep onset latency (sSOL), sleep efficiency (sSE), wake after sleep onset (sWASO), total sleep time (sTST), Fatigue Severity Scale, and Insomnia Severity Index were evaluated in subjects treated with medications for symptoms of depression/anxiety (subpopulation). Of 949 randomized subjects, 61 treated with medications for symptoms of depression/anxiety were included. In the subpopulation, CFB comparing LEM with placebo were generally smaller than the overall population due to a larger placebo response in the subpopulation. However, the magnitudes of CFB within the active treatment groups for sSOL, sWASO, sTST, and sSE were similar between the subpopulation and the overall population. No new safety signals were observed in the subpopulation. LEM treatment benefited subjects with insomnia treated with medications for depression/anxiety symptoms, with no new safety signals. A greater placebo response in the subpopulation than in the overall population decreased the drug versus placebo effect size for LEM, as has been reported for other insomnia medications.

Diary- and actigraphy-estimated nighttime sleep during the perinatal period: A multimethod study.

Accurate estimation of perinatal sleep is important for informing future research and multigenerational health interventions. We compared diary- and actigraphy-estimated sleep parameters during pregnancy and postpartum. We informed our interpretation of these analyses with participants' feedback about these sleep estimation methods. This preregistered study ( https://doi.org/10.17605/OSF.IO/UZFRD ) included 92 English-speaking, women-identified birthing parents who completed sleep diaries and wore wrist actigraphs for 7days during the 3rd trimester of pregnancy, 6weeks postpartum, and 16weeks postpartum. Sleep parameters included total sleep time (TST), sleep efficiency (SE), sleep onset latency (SOL), and wake after sleep onset (WASO). Multilevel models tested associations between diary and actigraphic sleep over time. Results indicated that diary and actigraphic sleep parameters were significantly associated over time, although actigraphic TST, SE, and SOL tended to be lower-and WASO longer-than diary estimations. WASO estimations were significantly more discrepant during 6weeks postpartum than during the 3rd trimester or 16weeks postpartum. Using conventional content analysis, three primary themes emerged from participants' feedback about sleep diaries and wrist actigraphs that enriched our interpretation of multilevel model results: (1) Wearability, (2) Functionality/Ease of Use, and (3) Measurement Accuracy. This study was the first to implement a multimethod design supplemented by qualitative data to investigate not only the association between diary and actigraphic perinatal sleep, but what it is like for birthing parents to engage with these sleep estimation methods. This study has important implications for behavioral medicine research and practice with perinatal populations.

Association Between Age and Co-Morbid Insomnia and Sleep Apnea

PurposeTo investigate the age-related prevalence of Co-Morbid Insomnia and Sleep Apnea (COMISA). MethodsA single-night polysomnography with video monitoring was conducted on 2,176 Chinese adults (ages 18-102) to screen for Obstructive Sleep Apnea (OSA). Insomnia was defined as difficulty initiating or maintaining sleep, or early morning awakening at least three times per week for more than three months, accompanied by daytime symptoms such as irritability, fatigue, or anxiety. ResultsOf the participants, 981 met the criteria for COMISA, defined by an apnea-hypopnea index (AHI) of ≥5 and the presence of insomnia. Compared to patients with OSA only (n=433), COMISA patients were more often female (48% vs. 24%), had longer sleep onset latency (5.8 minutes), shorter total sleep time (14.0 minutes), lower AHI (14.4 points), and higher mean peripheral oxygen saturation (0.6%; all p<0.05). The prevalence of COMISA versus OSA only was 51.9% vs. 48.1% in participants under 50 years, compared to 78.1% vs. 21.9% in those aged 70 or older. Logistic regression analysis adjusted for sex showed a 3% increase in the odds of COMISA (95% CI: 1.02-1.04) with each additional year of age. ConclusionsOur findings reveal a significant association between increasing age and the development of COMISA, underscoring the need for heightened clinical awareness of this condition in elderly patients.

Association between social jetlag and leisure-time physical activity and muscle strengthening exercise in young adults: findings from a nationally representative sample in South Korea

ObjectivesSocial jetlag (SJL), which is characterised by a misalignment between biological and social time, is associated with cardiometabolic risk factors. This study investigated the relationship between SJL, leisure-time physical activity (LTPA) and muscle strengthening exercise (MSE) in young adults. Study designThis was a cross-sectional study. MethodsThis cross-sectional study included a nationally representative sample of young adults aged 19–29 years (n = 2113). SJL was calculated as the difference in the midpoint of sleep onset and offset time between weekdays and weekends. The dependent variables were engagement in ≥150 min/week of moderate-to-vigorous LTPA and engagement in MSE ≥2 days/week based on guidelines provided by the World Health Organisation. Logistic regression analysis was performed to estimate odds ratios (ORs) and 95% confidence intervals (CIs). Non-linear relationships were estimated using restricted cubic spline regression. ResultsThe study population comprised 975 men and 1138 women. Among participants, 4.6% had <0 min, 41.9% had 0–59 min, 25.7% had 60–119 min and 27.7% had ≥120 min SJL. Those with ≥120 min SJL had a reduced likelihood of achieving the recommended level of LTPA (OR: 0.71, 95% CI: 0.52–0.95) and MSE (OR: 0.73, 95% CI: 0.55–0.97). In the non-linear model, an inverse U-shaped association was observed, wherein the highest probability of meeting the recommended level of LTPA and MSE was observed in those with 45 min SJL, decreasing after this threshold. ConclusionsIndividuals with ≥120 min SJL were less likely to engage in the recommended level of both aerobic and anaerobic exercise. Although future studies using a longitudinal design are required to elucidate the causal relationship between SJL and physical activity, the current findings suggest that physical inactivity during leisure time may play an important role in the increased risk of cardiometabolic abnormalities in young adults with SJL.

Designing work for healthy sleep: A multidimensional, latent transition approach to employee sleep health.

Healthy sleep is essential to employee well-being and productivity, but many modern workers do not obtain adequate sleep. Are technology-related changes to job design (i.e., computer use, sedentary work, nontraditional work schedules) related to long-term worsening of employee sleep health? The present study seeks to address this question using nationally representative data from the Midlife in the United States study, which includes detailed information on sleep duration, regularity, sleep onset latency, insomnia symptoms, napping, and daytime tiredness from full-time workers (N = 1,297) at two time points separated by approximately 10 years. Using latent transition analysis to consider how these sleep health dimensions co-occur, we identify three multidimensional sleep health phenotypes at both time points: good sleepers, catch-up sleepers, and insomnia sleepers. Sedentary work is linked to the insomnia sleeper phenotype. Nontraditional work schedules are linked to the catch-up sleeper phenotype. These findings test assumptions of modern models of job design regarding the impact of technology on employee sleep health and advance measurement of sleep health in the organizational sciences to be multidimensional and dynamic. Further, results point to specific sleep needs in the working adult population and identify potential points of intervention via job design. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

The Impact of Alpha-s1 Casein Hydrolysate On Chronic Insomnia: A Randomized, Double-Blind Controlled Trial

BackgroundAlpha-s1 casein hydrolysate (ACH; Lactium®) is recognized as a supplementary treatment to enhance sleep quality. However, limited studies utilizing objective sleep assessment tools have resulted in a lack of substantial validation. This study aimed to assess the effects of ACH on both subjective sleep assessments and objective polysomnography (PSG) recordings in a hospital-based cohort of Taiwanese individuals with chronic insomnia. MethodsIn this 4-week randomized, double-blind, placebo-controlled trial, 36 participants diagnosed with chronic insomnia were enrolled and randomly assigned to either the ACH or placebo groups. Initially, participants in the ACH group received 600 mg of ACH daily, which was reduced to 300 mg for the latter two weeks; the placebo group received maltodextrin capsules throughout the study. The study utilized polysomnography (PSG), along with detailed sleep questionnaires including the Insomnia Severity Index (ISI), Global Sleep Disorders Score (GSDS), Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), and Hospital Anxiety and Depression Scale (HADS), to assess improvements in sleep quality and related health markers. The efficacy of the intervention was assessed through measures of sleep efficiency, stage distribution, and psychological well-being, comparing results from before to after the treatment phase. ResultsThe study demonstrated that ACH treatment notably enhanced sleep quality, evidenced by significant improvements in ISI, GSDS, PSQI, ESS, and HADS scores at both week 2 and 4 (all p-values < 0.05) compared with baseline scores. When compared to the placebo group, the ACH group experienced a marked reduction in GSDS scores over time (p = 0.045). Furthermore, PSG data revealed a significant decrease in sleep onset latency from baseline in the ACH group compared to the placebo group (p = 0.012; -7.7 ± 16.0 minutes vs. 6.1 ± 17.7 minutes for ACH and placebo groups, respectively). These results indicate that ACH treatment effectively improved sleep initiation and overall sleep quality. ConclusionACH Supplementation significantly improved sleep quality, particularly by reducing GSDS scores and sleep onset latency, demonstrating its potential as an effective intervention for chronic insomnia. Future studies with larger samples and exploration of long-term effects are needed to confirm these results.

Stress Reactivity, Wellbeing and Functioning in University Students: A Role for Autonomic Activity During Sleep.

Sleep is a key biological mechanism in promoting wellbeing and resilience to stress. This cross-sectional study examined connections between sleep, autonomic function, wellbeing, and stress reactivity in healthy individuals. Demographic, lifestyle, sleep, and psychological well-being information were collected from 85 healthy university students. These variables were analysed in conjunction with indices of cardiac autonomic activity, including heart rate and high frequency heart rate variability (HF HRV, an indicator of parasympathetic vagal tone) recorded during nocturnal sleep onset and in response to a cognitive stressor. Correlational analyses revealed that unrefreshing and fragmented sleep was strongly associated with lower HF HRV at sleep onset, suggestive of poorer autonomic de-arousal. Further, those with minimal increases in HF HRV from wakefulness to sleep reported worse sleep quality and greater challenges in daily activities compared to those with significant increases. This same group also demonstrated significantly greater reactivity and slower recovery when faced with a stressor the next day, as evidenced by comparison of heart rate values. Our findings suggest an association between autonomic hypervigilance and aspects of sleep quality, with potential implications for wellbeing and stress responses.

Evaluation of sleep health in children with congenital adrenal hyperplasia due to 21-hydroxylase deficiency.

Literature on sleep health in children with congenital adrenal hyperplasia (CAH) is sparse despite the important role the hypothalamic-pituitary-adrenal (HPA) axis plays in sleep onset, duration, and awakenings after sleep onset. To evaluate sleep health in children and adolescents with CAH as measured by wrist actigraphy and validated sleep questionnaires. Cross-sectional study at our multidisciplinary CAH clinic. Participants aged 3-18 years with classic CAH wore an ActiGraph GT3X+ accelerometer for one week. Children and parents completed sleep questionnaires and the results were compared to published samples from the community and children with sleep disorders (clinical). Actigraphy sleep health measures were compared to consensus sleep duration recommendations and normative data in healthy children. Forty-four participants (23 males) with CAH completed the study. Actigraphy found sleep duration in children with CAH was less than recommended guidelines with significantly worse sleep efficiency and increased wake after sleep onset (p<0.05) compared to healthy children. After sleep onset, the average number of awakenings increased from 1.67 per hour during the first two hours post evening hydrocortisone dose to 3.12 per hour 4 to 7 hours post dose, corresponding with washout of the evening hydrocortisone dose. Parents of 3-10-year-olds reported significantly worse sleep onset delay and decreased sleep duration than both the community and clinical samples, and significantly more night awakenings than the community sample. Our findings suggest that sleep health is impaired in children with CAH and is an important consideration for both clinical practice and future research.

The effect of altered sleep timing on glycaemic outcomes: Systematic review of human intervention studies.

Alterations in sleep timing can lead to disturbances in glycaemic control, although the evidence is inconsistent. Therefore, this systematic review summarizes results from human intervention studies of altered sleep timing on glycaemic outcomes. As part of a broader search on the effect of altering timing of sleep, physical activity and dietary intake, Medline and Embase were searched from inception to February 2023, and subsequent reference searches were done. With the help of a machine learning-aided program 'ASReview', we selected any type of intervention study in the general adult population, which acutely delayed sleep by ≥2 h for at least one night, while the total time in bed was the same between early and late sleep. Quality assessment was done using the quality assessment tool for quantitative studies. In total, 14 studies (159 adults with normal or increased weight) were identified. Methodological quality was high (n = 4), moderate (n = 7) or low (n = 3). Acute delays of sleep onset showed unfavourable effects in 10 out of 27 measured glycaemic outcomes (one-six studies reported on each outcome) with outcomes mostly measured in the postprandial period, compared to (early) nighttime sleep. Acutely delaying sleep timing might have unfavourable effects on glycaemic outcomes, compared to (early) nighttime sleep. Future research does however need better controlled trials, also measuring and controlling sleep quantity, sleep quality, physical activity and dietary intake, with longer follow-up periods, consistent outcomes and designs and more diverse populations to provide targeted advice regarding the optimal timing for sleep. This review is part of a larger search 'The effect of altering timing of physical activity, sleep and energy intake on glycaemia and Type 2 Diabetes risk in humans', of which the protocol was registered in the PROSPERO database on 27 November 2021 under number: CRD42021287828.

No negative impact of a vibro-tactile supine-avoidance alarm on sleep onset latency following supine posture shifts during sleep.

It is unclear to what extent posture shifts during sleep are associated with prior arousal and full awakening, and if supine-avoidance alarms to discourage supine sleep promote more extended wake following supine alarms. Thus, this study sought to examine relationships between posture shifts, arousals and awakenings, and to establish if a vibro-tactile supine-avoidance alarm delays the return to sleep following supine posture shifts. Detailed posture shift and sleep data from a chest-worn device with an inactive or active supine-avoidance alarm, and in-home sleep study data were from 37 participants who completed a randomised controlled trial of supine-avoidance device treatment for supine-predominant obstructive sleep apnea. Posture shifts, sleep, arousal and awakening responses, and sleep onset latency following posture shifts were compared between baseline and supine-avoidance treatment nights. Compared to baseline, there was a marked reduction in overnight supine time with active supine-avoidance treatment. Around 90% of posture shifts were preceded by either wake, arousal or full awakening. Sleep onset latency was longer for posture shifts occurring from prior wake compared to those from prior sleep but was not different between baseline or supine-avoidance treatment nights or between shifts from non-supine to supine or vice-versa. Most overnight posture shifts are associated with either prior wake or brief arousal, which likely facilitates co-ordinated body movements needed for effective posture shifts. Thus, sleep is typically already interrupted around the time that supine-avoidance alarms are activated, and the alarm itself does not significantly delay the return to sleep.

Minimal changes in sleep parameters during overnight ambulatory blood pressure monitoring do not affect outcomes.

Ambulatory blood pressure monitoring (ABPM) is considered the gold standard for assessing blood pressure; however, its use may potentially disrupt sleep. Previous studies have produced mixed results on the impact of ABPM on sleep parameters and used actigraphy as the evaluating tool. To date, no studies have investigated the effects of ABPM on sleep parameters evaluated through polysomnography. This study aimed to examine the effects of ABPM on objectively assessed sleep parameters. We evaluated five women and five men (age: 38.0 ± 15.0 years; BMI: 27.0 ± 3.5kg/m²) using full polysomnography over two nights in a sleep laboratory-one night with ABPM and one night without it, with nocturnal assessments every 30min. The order of the conditions was randomized, with intervals between nights ranging from 3 to 10 days. N2 sleep was significantly longer during the night with ABPM compared to the night without it (66.4 ± 12.4% vs. 57.7 ± 11.3%, p < 0.003). Conversely, the apnea-hypopnea index was higher on the night without ABPM (13.1 ± 21.2 vs. 10.5 ± 19.8 events/hour, p < 0.005). Participants did not rate the night with ABPM as worse than the night without, and no significant differences were observed in total sleep time, sleep latency, sleep efficiency, number of awakenings, or time awake after sleep onset. ABPM does not appear to adversely affect significant objective sleep parameters or subjective evaluations of sleep quality.