Corrigendum: Preventing sleep disruption with bright light therapy during chemotherapy for breast cancer: a phase II randomized controlled trial.

[This corrects the article DOI: 10.3389/fnins.2022.815872.].

Supplemental ambient lighting intervention to improve sleep in Parkinson's disease: A pilot trial.

IMPORTANCE: Sleep disturbances in Parkinson's disease (PD) are common and often adversely affect quality of life. Light therapy has benefited sleep quality and mood outcomes in various populations but results to date with conventional light therapy boxes in PD patients have been mixed. We hypothesized that a passive lighting intervention, applied in the morning and designed to maximally affect the circadian system, would improve measures of sleep and mood in PD patients. METHODS: In this single-arm, within-subjects intervention study, baseline objective sleep (actigraphy), subjective sleep quality (questionnaires), and subjective mood (questionnaires) data were collected for 1 week. Lighting was then administered to participants via table/floor lamps installed in the home or via personal light therapy glasses for 2 h in the morning, 7 days per week, over the following 4-week period. Post-intervention data for the same outcomes were collected during the final week of the intervention period. RESULTS: Among 20 participants (12 women, 8 men; mean [SD] age 72.1 [9.5] years, disease duration 9.0 [5.2] years), objective sleep duration increased significantly by 28.5 min (p = 0.029) and objective sleep time increased significantly by 19.9 min (p = 0.026). CONCLUSION: Passive and easily administered lighting interventions for improving sleep in PD patients hold promise as a treatment for mitigating symptoms and improving quality of life in PD.

The Role of Sleep in Links Between Daily Interpersonal Stress and Internalizing and Externalizing Symptoms During Middle Childhood.

Background: Interpersonal stress has been consistently linked with poorer adjustment, and healthy sleep may play a promotive or protective role in this relation. However, little is known regarding such associations among children. The current study examined longitudinal associations between daily interpersonal stress, sleep, and internalizing/externalizing symptoms during middle childhood. Methods: At age 8 years, participants wore actigraphy watches for 7 days to capture sleep, and primary caregivers reported on children's daily interpersonal stress, internalizing/externalizing symptoms, and sleep problems. At age 9 years, children self-reported symptoms. Results: Greater daily interpersonal stress at age 8 years predicted greater internalizing/externalizing symptoms at age 9 years. Higher sleep efficiency predicted fewer externalizing symptoms. Sleep duration moderated links between interpersonal stress and internalizing/externalizing symptoms, but associations were positive and significant for children with average and high duration only. Conclusion: Findings advance our understanding of links between interpersonal stress, sleep, and child adjustment and can inform targeted family and school interventions.

Fact or Fiction-Accelerometry Versus Self-Report in Adherence to Pediatric Concussion Protocols: Prospective Longitudinal Cohort Study.

Background: Concussion, or mild traumatic brain injury, is a growing public health concern, affecting approximately 1.2% of the population annually. Among children aged 1-17 years, concussion had the highest weighted prevalence compared to other injury types, highlighting the importance of addressing this issue among the youth population. Objective: This study aimed to assess adherence to Return to Activity (RTA) protocols among youth with concussion and to determine if better adherence affected time to recovery and the rate of reinjury. Methods: Children and youth (N=139) aged 5-18 years with concussion were recruited. Self-reported symptoms and protocol stage of recovery were monitored every 48 hours until symptom resolution was achieved. Daily accelerometry was assessed with the ActiGraph. Data were collected to evaluate adherence to the RTA protocol based on physical activity cutoff points corresponding to RTA stages. Participants were evaluated using a battery of physical, cognitive, and behavioral measures at recruitment, upon symptom resolution, and 3 months post symptom resolution. Results: For RTA stage 1, a total of 13% of participants were adherent based on accelerometry, whereas 11% and 34% of participants were adherent for stage 2 and 3, respectively. The median time to symptom resolution was 13 days for participants who were subjectively reported adherent to the RTA protocol and 20 days for those who were subjectively reported as nonadherent (P=.03). No significant agreement was found between self-report of adherence and objective actigraphy adherence to the RTA protocol as well as to other clinical outcomes, such as depression, quality of life, and balance. The rate of reinjury among the entire cohort was 2% (n=3). Conclusions: Overall, adherence to staged protocols post concussion was minimal when assessed with accelerometers, but adherence was higher by self-report. More physical activity restrictions, as specified in the RTA protocol, resulted in lower adherence. Although objective adherence was low, reinjury rate was lower than expected, suggesting a protective effect of being monitored and increased youth awareness of protocols. The results of this study support the move to less restrictive protocols and earlier resumption of daily activities that have since been implemented in more recent protocols.

Attenuated melanopsin-mediated post-illumination pupillary response (PIPR) is associated with reduced actigraphic amplitude and mesor in older adults.

STUDY OBJECTIVES: This study aimed to explore the relationship between post-illumination pupillary response (PIPR) with sleep and circadian measures in a community sample of healthy older adults. METHODS: Eligible participants were invited to complete a one-week sleep diary, actigraphy and provide an overnight urine sample to measure urinary 6-sulfatoxymelatonin (aMT6s). PIPR was defined as the as the pupil constriction at 6s post-stimulus (PIPR-6s), and ii) for 30s beginning 10s after stimulus (PIPR-30s) normalized as a percentage to the baseline pupil diameter, after 1s of blue and 1s of red-light stimulus, respectively. The Net-PIPRs were reported by subtracting the PIPR to red stimulus from the PIPR to blue stimulus. The relationship between PIPR metrics to aMT6s and actigraphic rest-activity rhythm parameters was examined by generalized linear models. RESULTS: A total of 48 participants were recruited (Mean age: 62.6 ± 7.1 years, Male: 44%). Both Net PIPR-6s and Net PIPR-30s were significantly associated with actigraphic rest-activity amplitude (B=0.03, p=0.001 and B=0.03, p=0.01, respectively), and actigraphic rest-activity mesor (B=0.02, p=0.001 and B=0.03, p=0.004, respectively). Additionally, the Net PIPR-30s were positively associated with overnight aMT6s level (B=0.04, p=0.03), and negatively associated with actigraphic rest-activity acrophase (B=-0.01, p=0.004) in the fully adjusted models. CONCLUSION: Attenuated PIPR is associated with a reduced actigraphic amplitude and mesor. The reduced retinal light responsivity may be a potential pathway contributing to impaired photic input to the circadian clock and resulted in the age-related circadian changes in older adults.

Cognitive correlates of circadian rhythm and sleep-wake behaviour in chronic obstructive pulmonary disease patients.

Chronic obstructive pulmonary disease (COPD) patients often experience reduced physical activity, sleep disturbances, and cognitive impairment. However, reports on measurement of rest-activity rhythm and sleep-wake behavior and their impact on cognitive functions in COPD patients are limited. This study aimed to objectively measure circadian rhythms (rest-activity and ambient illuminance) and sleep behaviors in clinically stable COPD patients and their relationship with cognitive functions. The study involved 65 male COPD patients and 50 age-matched controls, monitored over 3-7 days using actigraphy. Cognitive status was assessed using the Montreal Cognitive Assessment (MoCA) followed by short interbal time estimation via time production and reproduction with reaction time measurement using TimeProd software. Findings indicated significant disruptions in circadian rhythms in COPD patients, characterized by lower mesor, amplitude, and autocorrelation coefficients compared to controls. Patients also reported poorer sleep quality and higher sleep fragmentation, with 85.7% displaying cognitive impairment. Notably, longer time estimations, increased variability in task performance, and slower reaction times suggested cognitive deterioration. Positive correlations emerged between rhythm parameters (amplitude and circadian quotient) and cognitive performance metrics. This highlights the relevance of circadian and sleep disturbances in COPD, suggesting that addressing these rhythms could help mitigate cognitive decline, potentially through chronotherapeutic strategies.

The effects of daylight saving time clock changes on accelerometer-measured sleep duration in the UK Biobank.

We explored the effects of daylight saving time clock changes on sleep duration in a large accelerometer dataset. Our sample included UK Biobank participants (n = 11,780; aged 43-78 years) with accelerometer data for one or more days during the 2 weeks surrounding the Spring and Autumn daylight saving time transitions from October 2013 and November 2015. Between-individual t-tests compared sleep duration on the Sunday (midnight to midnight) of the clock changes with the Sunday before and the Sunday after. We also compared sleep duration on all other days (Monday-Saturday) before and after the clock changes. In Spring, mean sleep duration was 65 min lower on the Sunday of the clock changes than the Sunday before (95% confidence interval -72 to -58 min), and 61 min lower than the Sunday after (95% confidence interval -69 to -53). In Autumn, the mean sleep duration on the Sunday of the clock changes was 33 min higher than the Sunday before (95% confidence interval 27-39 min), and 38 min higher than the Sunday after (95% confidence interval 32-43 min). There was some evidence of catch-up sleep after both transitions, with sleep duration a little higher on the Monday-Friday than before, although this was less pronounced in Autumn. Future research should use large datasets with longer periods of accelerometer wear to capture sleep duration before and after the transition in the same individuals, and examine other aspects of sleep such as circadian misalignment, sleep fragmentation or daytime napping.

Sleep Characteristics of Children and Youth with Cerebral Palsy.

Background: Children with cerebral palsy are considered to be a population at risk for the occurrence of sleep difficulties. However, existing literature has been limited by subjective measures of sleep and has failed to examine contributing factors. Methods: Forty-five youth with cerebral palsy participated. Both youth and caregivers completed sleep-related questionnaires, while youth completed daily actigraphy for objective sleep assessments. Results: Sleep patterns, including sleep duration, wake after sleep onset, and sleep efficiency, are generally aligned with existing sleep recommendations. However, the number of awakenings was significantly higher in youth with cerebral palsy compared to these recommendations. Most youth experienced poor sleep quality, and approximately a quarter experienced insomnia. Being a boy and having a preexisting mental health diagnosis was associated with poor sleep quality and greater insomnia symptoms. Conclusions: Most youth with cerebral palsy experience a range of sleep difficulties. This study provides new information on sleep patterns in youth with cerebral palsy, highlighting the importance of addressing sleep issues in this population to improve their well-being and ultimately limit the negative impacts on overall health and quality of life.

The Validation of the SOMNOwatch™ Actigraphy System for Periodic Limb Movements in Sleep Assessment.

There is a growing body of evidence regarding the clinical significance of PLMS, and this movement disorder is of concern in both clinical and scientific contexts. Leg actigraphy is a convenient and promising method for screening periodic limb movements in sleep (PLMSs). This study aims to demonstrate the reliability of the SOMNOwatch™ actigraph for detecting periodic limb movements in sleep. Twenty-eight patients, referred to a sleep laboratory for various sleep problems, underwent nocturnal polysomnography with simultaneous one-sided actigraphy using the SOMNOwatch™ actigraph. Recordings of leg movements obtained from both methods were manually scored, calculating the periodic limb movement index (PLMI). The agreement between the methods was assessed through correlation analysis and event-by-event comparison. The correlation between the PLMI derived from PSG and SOMNOwatch™ was high and statistically significant (r = 0.98, p < 0.0001). The SOMNOwatch™ demonstrated a sensitivity of 86.7% and a specificity of 92.3% in detecting PLMS. Similarly, for detecting patients with a PLMI equal to or greater than 15, the sensitivity was 85.7%, and the specificity was 95.2%.

A replicate crossover trial on the inter-individual variability of sleep indices in response to acute exercise undertaken by healthy men.

STUDY OBJECTIVES: Using the necessary replicate-crossover design, we investigated whether there is inter-individual variability in home-assessed sleep in response to acute exercise. METHODS: Eighteen healthy men (mean(SD): 26(6) years) completed two identical control (8-h laboratory rest, 08:45-16:45) and two identical exercise (7-h laboratory rest; 1-h laboratory treadmill run [62(7)% peak oxygen uptake], 15:15-16:15) trials in randomised sequences. Wrist-worn actigraphy (MotionWatch 8) measured home-based sleep (total sleep time, actual wake time, sleep latency, sleep efficiency) two nights before (nights 1-2) and three nights after (nights 3-5) the exercise/control day. Pearson's correlation coefficients quantified the consistency of individual differences between the replicates of control-adjusted exercise responses to explore: (1) immediate (night 3 minus night 2); (2) delayed (night 5 minus night 2); and (3) overall (average post-intervention minus average pre-intervention) exercise-related effects. Within-participant linear mixed models and a random-effects between-participant meta-analysis estimated participant-by-trial response heterogeneity. RESULTS: For all comparisons and sleep outcomes, the between-replicate correlations were non-significant, ranging from trivial-to-moderate (r range = -0.44 to 0.41, P≥0.065). Participant-by-trial interactions were trivial. Individual differences SDs were small, prone to uncertainty around the estimates indicated by wide 95% confidence intervals and did not provide support for true individual response heterogeneity. Meta-analyses of the between-participant, replicate-averaged condition effect revealed that, again, heterogeneity (τ) was negligible for most sleep outcomes. CONCLUSION: Control-adjusted sleep in response to acute exercise was inconsistent when measured on repeated occasions. Inter-individual differences in sleep in response to exercise were small compared to the natural (trial-to-trial) within-subject variability in sleep outcomes.

Genetic variants associated with chronic fatigue syndrome predict population-level fatigue severity and actigraphic measurements.

STUDY OBJECTIVES: The diagnosis of myalgic encephalomyelitis/chronic fatigue syndrome (CFS) is based on a constellation of symptoms which center around fatigue. However, fatigue is commonly reported in the general population by people without CFS. Does the biology underlying fatigue in patients with CFS also drive fatigue experienced by individuals without CFS? METHODS: We used UK Biobank actigraphy data to characterize differences in physical activity patterns and daily temperature rhythms between participants diagnosed with CFS compared to controls. We then tested if single nucleotide variants (SNVs) previously associated with CFS are also associated with the variation of these actigraphic CFS correlates and/or subjective fatigue symptoms in the general population. RESULTS: Participants diagnosed with CFS (n = 295) had significantly decreased overall movement (Cohen's d = 0.220, 95% CI of -0.335 to -0.106, p-value = 2.42x10-15), lower activity amplitudes (Cohen's d = -0.377, 95% CI of -0.492 to -0.262, p-value = 1.74x10-6), and lower wrist temperature amplitudes (Cohen's d = -0.173, 95% CI of -0.288 -0.059, p-value = 0.002) compared to controls (n = 63,133). Of 30 tested SNVs associated in the literature with CFS, one was associated in the control population with subjective fatigue and one with actigraphic measurements (FDR < 0.05). CONCLUSIONS: The genetic overlap of CFS risk with actigraphy and subjective fatigue phenotypes suggests that some biological mechanisms underlying pathologic fatigue in CFS patients also underlie fatigue symptoms at a broader population level. Therefore, understanding the biology of fatigue in general may inform our understanding of CFS pathophysiology.

From Counting Dollars to Counting Sheep: Exploring Simultaneous Change in Economic Well-Being and Sleep among African American Adolescents.

In the U.S.A., Black/African American adolescents disproportionately experience short and poor-quality sleep, and there is little understanding of why some experience decrements or improvements in sleep over time. Toward conducting culturally specific research and identifying processes that uniquely explain variability within a racial/ethnic group, we utilized a within-group design to examine socioeconomic status (SES) as a predictor of Black adolescents' sleep. Few studies have examined change-on-change processes in sleep over time. Contributing to the literature in novel ways, we assessed the predictive effect of change in SES over one year on changes in four actigraphy-derived sleep parameters over the same time period. Participants were 218 Black adolescents (Time 1: Mage = 17.09 years; 54.6% female) and their mothers from socioeconomically diverse backgrounds. Adolescents participated in two-waves of data collection spaced approximately one year apart. At each wave, we assessed economic well-being (used to index SES) and sleep using 7 nights of actigraphy from which we derived measures of sleep duration (minutes) and quality (efficiency, long-wake episodes, activity). Latent difference score analyses revealed that adolescents experiencing increases in SES over one year exhibited decreases in both long-wake episodes and sleep activity over one year. Findings suggest that individual differences in change in SES explain individual differences in change in adolescents' sleep quality. Notably, findings highlight the utility of within-group designs for identifying culturally specific processes that predict improvements in sleep quality in a sample at disproportionate risk for sleep and health disparities.

Associations of Advanced Glycation End Products with Sleep Disorders in Chinese Adults.

BACKGROUND: Advanced glycation end products (AGEs), a group of food processing byproducts, have been implicated in the development of various diseases. However, the relationship between circulating AGEs and sleep disorders remains uncertain. METHODS: This cross-sectional study elucidated the association of plasma AGEs with sleep disorders among 1732 Chinese adults who participated in the initial visit (2019-2020) of the Tongji-Shenzhen Cohort (TJSZC). Sleep behavior was assessed using self-reported questionnaires and precise accelerometers. Plasma levels of AGEs, including Nε-(Carboxymethyl)lysine (CML), Nε-(Carboxyethyl)lysine (CEL), and Nδ-(5-hydro-5-methyl-4-imidazolone-2-yl)-ornithine (MG-H1), were quantified by ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). RESULTS: In logistic regression, per IQR increment in individual AGEs was associated with an increased odds ratio of short sleep duration (CML: 1.11 [1.00, 1.23]; CEL: 1.16, [1.04, 1.30]), poor sleep quality (CML: 1.33 [1.10, 1.60]; CEL: 1.53, [1.17, 2.00]; MG-H1: 1.61 [1.25, 2.07]), excessive daytime sleepiness (CML: 1.33 [1.11, 1.60]; MG-H1: 1.39 [1.09, 1.77]), and insomnia (CML: 1.29 [1.05, 1.59]). Furthermore, in weighted quantile sum regression and Bayesian kernel machine regression analyses, elevated overall exposure levels of plasma AGEs were associated with an increased risk of sleep disorders, including short sleep duration, poor sleep quality, excessive daytime sleepiness, and insomnia, with CML being identified as the leading contributor. Insufficient vegetable intake and higher dietary fat intake was associated with an increase in plasma CEL. CONCLUSIONS: These findings support a significant association between plasma AGEs and sleep disorders, indicating that AGEs may adversely influence sleep health and reducing the intake of AGEs may facilitate preventing and ameliorating sleep disorders.

Preliminary report: Sleep duration during late pregnancy predicts postpartum emotional responses among parents at risk for postpartum depression.

Introduction: Sleep loss is common during the perinatal period; however, few studies have assessed potential consequences of insufficient sleep for postnatal emotional responding, a key contributor to parenting behaviors with implications for parent-infant bonding and mental health. To generate hypotheses for future work assessing perinatal sleep and emotion-related outcomes, this pilot study explored whether prenatal sleep duration predicted postnatal emotional responding in a sample at risk for postpartum depression. Methods: Participants were nine birthing parents with a prior mood disorder who were not in a current episode at enrollment. We estimated sleep with actigraphy collected for 1 week at 33 weeks' gestation and at 2 and 6 weeks postpartum. Following each week, participants completed an emotional evaluation task, rating the valence and arousal of standardized images from the International Affective Picture System. We tested whether average prenatal (33 weeks) nighttime sleep duration predicted concurrent and future responsiveness to emotional images, quantified by participants' reaction times and arousal/valence ratings. Results: Shorter prenatal sleep duration predicted faster reaction times, both concurrently and at 2 weeks postpartum (ps ≤ .05), as well as lower arousal ratings for negative images at 2 and 6 weeks postpartum (ps ≤ .043). Conclusions: In this small sample of birthing parents at risk for postpartum depression, shorter prenatal sleep duration predicted faster reactions to emotional stimuli and blunted arousal responses to negative images. Although preliminary, these findings justify further study of the role of prenatal sleep in postpartum emotional responses and how these factors may impact parent-infant outcomes.

Closed-Loop Therapy and Sleep in Young People Newly Diagnosed With T1D and Their Parents.

BACKGROUND: A diagnosis of type 1 diabetes in a young person can create vulnerability for sleep. Historically it has been rare for young people to be offered a closed-loop system soon after diagnosis meaning that studies examining sleep under these circumstances in comparison with standard treatment have not been possible. In this study, we examine sleep in young people (and their parents) who were provided with hybrid closed-loop therapy at diagnosis of type 1 diabetes versus those who receive standard treatment over a 2-year period. METHODS: The sample comprised 97 participants (mean age = 12.0 years; SD = 1.7) from a multicenter, open-label, randomized, parallel trial, where young people were randomized to either hybrid closed-loop insulin delivery or standard care at diagnosis. Sleep was measured using actigraphy and the Pittsburgh Sleep Quality Index (PSQI) in the young people, and using the PSQI in parents. RESULTS: Sleep in young people using hybrid closed-loop insulin delivery did not differ significantly compared with those receiving standard care (although there were nonsignificant trends for better sleep in the closed-loop group for 4 of the 5 sleep actigraphy measures and PSQI). Similarly, there were nonsignificant differences for sleep between the groups at 24 months (with mixed direction of effects). CONCLUSIONS: This study assessed for the first time sleep in young people using a closed-loop system soon after diagnosis. Although sleep was not significantly different for young people using closed-loop insulin delivery as compared with those receiving standard care, the direction of effects of the nonsignificant results indicates a possible tendency for better sleep quality in the hybrid closed-loop insulin delivery group at the beginning of the treatment.

Sex differences in the role of sleep on cognition in older adults.

Study Objectives: The study aimed to investigate sex differences in the relationship between sleep quality (self-report and objective) and cognitive function across three domains (executive function, verbal memory, and attention) in older adults. Methods: We analyzed cross-sectional data from 207 participants with normal cognition (NC) or mild cognitive impairment (89 males and 118 females) aged over 60 years. The relationship between sleep quality and cognitive performance was estimated using generalized additive models. Objective sleep was measured with the GT9X Link ActiGraph, and self-reported sleep was measured with the Pittsburgh Sleep Quality Index. Results: We found that females exhibited lower executive function with increased objective total sleep time, with a steeper decline in performance after 400 minutes (p = .015). Additionally, longer objective sleep correlated with lower verbal memory linearly (p = .046). In males, a positive linear relationship emerged between objective sleep efficiency and executive function (p = .036). Self-reported sleep was not associated with cognitive performance in females and males with NC. However, in males with cognitive impairment, there was a nonlinear positive relationship between self-reported sleep and executive function (p < .001). Conclusions: Our findings suggest that the association between sleep parameters on cognition varies between older males and females, with executive function being most strongly associated with objective sleep for both sexes top of form. Interventions targeting sleep quality to mitigate cognitive decline in older adults may need to be tailored according to sex, with distinct approaches for males and females.

Changes in Sleep of Families After the Arrival of an Autism Service Dog.

This study aimed to investigate the changes in sleep quality and quantity among families following the arrival of an autism service dog. We hypothesized that the sleep of the child or adolescent with autism spectrum disorder (assessed objectively with actigraphy and subjectively with a parent-reported sleep diary), and of both parents (assessed by self-reported diaries) would improve after the dog's arrival. The sleep of 18 youths (15 boys) aged from 5 to 16 years (M = 8.86), and of their parents (14 mothers, 11 fathers) was assessed for a 5- to 7-day period before (pretest) and eight to ten weeks after the dog's arrival (posttest). A designated parent (the same at the pretest and posttest) completed the sleep diary of the child, who wore an actiwatch in the meantime. Significant improvement in most sleep parameters was observed from pretest to posttest for the child and the mother, as reported in the sleep diaries. However, there was no improvement in the child's sleep when assessed objectively. Fathers' sleep duration increased after the dog's arrival, when adjusting for the child's age. All significant effects had medium to large sizes. This study provides the first quantitative evidence of the positive effect of autism service dogs on the sleep of families. These findings suggest that the dog's presence may increase the sense of safety for the child, who would resume sleeping faster or stay in the bedroom after nocturnal awakenings, leading to improved parents' sleep.

Higher Levels of Morning and Daytime Light Exposure Associated with Positive Sleep Indices in Professional Team Sport Athletes.

Objective: Light exposure techniques have been recommended to combat sleep issues caused by disruption to circadian regularity in the athletic population, although studies are lacking. Methods: A total of 17 professional male Australian Football athletes (age ± SD: 22 ± 3 years) wore a wrist actigraph to measure sleep parameters, and a wearable light sensor to measure melanopic equivalent daylight illuminance (mEDI, in lux) for 14 days. Participants completed three sleep questionnaires at the end of the data collection period and completed well-being surveys 6 times. The Sleep Regularity Index (SRI) for each player was also calculated from actigraphy data. Light exposure data were organised into three different timeframes: morning (wake time + 2 hours), daytime (end of morning to 6 pm), and evening (2 hours leading up to bedtime) for analysis. Repeated measures correlation was conducted for objective sleep measures and mEDI values per timeframe. Pearson's correlation was conducted on subjective sleep measures and well-being measures against mEDI values per timeframe. Results: Higher morning light was associated with significantly (p < 0.001) greater total sleep time (r = 0.31). Higher daytime light exposure was associated with higher subjective sleep quality (r = 0.48, p < 0.05). Higher evening light exposure was associated with higher Athlete Sleep Screening Questionnaire (ASSQ) global scores (r = 0.52, p < 0.05). There were no other significant correlations between light exposure and sleep or well-being measures (p > 0.05). Conclusion: Higher morning and daylight exposure levels were associated with various positive objective and subjective sleep measures in professional team sport athletes, supporting the need for education on optimising light exposure to improve circadian function, sleep, and health.

Association between sleep disturbances during pregnancy and adverse perinatal outcomes.

OBJECTIVE: To describe the changes in sleep pattern throughout pregnancy and to evaluate the relationship between sleep and adverse perinatal outcomes. METHODS: Pregnant women at Qianfoshan Hospital completed questionnaires regarding their sleep during each of the three trimesters. Additionally, a subset of participants engaged in objective sleep monitoring using actigraphy devices. In the perinatal period, the following data were collected: pregnancy complications; gestational age; mode of delivery; Apgar scores for the neonate; and birth weight. RESULTS: The total night sleep time in the second trimester was about 15 minutes shorter than that in the first trimester (P=0.024), and about 31 minutes shorter in the third trimester than in the second trimester (P<0.001). The sleep efficiency in the second trimester was about 10.23% lower than in the first trimester (P<0.001), and the efficiency in the third trimester was about 5.16% lower than in the second trimester (P<0.001). The occurrence of pregnancy-induced hypertension (PIH) was associated with sleep duration (P=0.019), sleep efficiency (P<0.001) and PSQI scores (P<0.001) in the first trimester. Furthermore, the mode of delivery was also found to be associated with sleep duration (P=0.011), sleep efficiency (P<0.001) and PSQI scores (P<0.001) in the first trimester. CONCLUSION: With the development of the pregnancy process, the sleep situation gets worse. Pregnant women's sleep situation in the first trimester of pregnancy is associated with the occurrence of PIH and delivery mode.

Evaluation of the Garmin Vivofit 4 for assessing sleep in youth experiencing sleep disturbances.

Objective: Wearable monitors are increasingly used to assess sleep. However, validity is unknown for certain monitors and populations. We tested the Garmin Vivofit 4 in a pediatric clinical sample. Methods: Participants (n = 25) wore the monitor on their nondominant wrist during an overnight polysomnogram. Garmin and polysomnography were compared using 95% equivalence testing, mean absolute error, and Bland-Altman analysis. Results: On average (mean ± SD), the Garmin predicted later sleep onset (by 0.84 ± 1.60 hours) and earlier sleep offset (by 0.34 ± 0.70 hours) than polysomnography. The resulting difference for total sleep time was -0.55 ± 1.21 hours. Sleep onset latency was higher for Garmin than polysomnography (77.4 ± 100.9 and 22.8 ± 20.0 minutes, respectively), while wake after sleep onset was lower (5.2 ± 9.3 and 43.2 ± 37.9 minutes, respectively). Garmin sleep efficiency averaged 3.3% ± 13.8% lower than polysomnography. Minutes in light sleep and deep sleep (the latter including rapid eye movement) were within ±3.3% of polysomnography (both SDs = 14.9%). No Garmin means were significantly equivalent with polysomnography (adjusted p > 0.99). Mean absolute errors were 0.47 to 0.95 hours for time-based variables (sleep onset, offset, and latency, plus total sleep time and wake after sleep onset), and 8.9% to 21.2% for percentage-based variables (sleep efficiency and sleep staging). Bland-Altman analysis showed systematic bias for wake after sleep onset, but not other variables. Conclusions: The Vivofit 4 showed consistently poor individual-level validity, while group-level validity was better for some variables (total sleep time and sleep efficiency) than others.