Objective Sleep Quality Research Articles

CON/DISCORDANCE BETWEEN SUBJECTIVE AND OBJECTIVE SLEEP PARAMETERS AND THEIR ASSOCIATION WITH COGNITIVE FUNCTION

Abstract Studies report that subjective and objective sleep parameters often do not agree with each other. This study examined if discordance between subjective and objective sleep measures are associated with cognition. Participants from the Midlife in the United States study (n=627) provided subjective (self-report) and objective (actigraphy) sleep duration and sleep quality. Discordance was assessed by absolute difference between subjective and objective z-scores in each sleep variable. Cognitive function was measured by the Brief Test of Adult Cognition by Telephone (BTACT). The correlations between subjective and objective sleep measures were weak-to-moderate (r=.43, .18 for duration and quality, respectively). Discordance scores in sleep duration and quality were each significantly associated with BTACT, such that greater discrepancy was associated with poorer cognitive function. These associations remained persistent after adjusting for sociodemographic differences. Results suggest that discordance between subjective and objective sleep parameters may relate to cognitive abilities needed to accurately monitor sleep characteristics.

Objective and subjective sleep health in adolescence: Associations with puberty and affect.

Sleep health tends to worsen during adolescence, partially due to pubertal-related changes that, in combination with social and psychological factors, can lead to long-lasting impairments in sleep health and affective functioning. Discrepant findings between subjective and objective measures of sleep in relation to affect have been reported in studies of adults; however, few investigations have assessed both subjective and objective sleep quality in a single sample, and fewer have examined this in the context of pubertal development. We aimed to (1) characterise pubertal associations with subjective sleep satisfaction, objective sleep efficiency, and objective and subjective sleep duration in adolescents; (2) examine the longitudinal association between daily affect and sleep metrics; and (3) test whether pubertal stage moderated this association. Eighty-nine participants (64% female, ages 13-20) completed an ecological momentary assessment (EMA) and actigraphy protocol. Independent of age, advanced pubertal stage was associated with lower subjective sleep satisfaction but not with objective sleep indices. Subjective sleep satisfaction was associated with within-person trajectories of negative affect, but not with positive affect. Pubertal stage and sleep satisfaction did not interact to predict within-day negative or positive affect. These findings are consistent with previous reports showing that objective and subjective sleep health are associated differently with puberty, and that subjective sleep health is associated with daily affect. Pubertal stage may be a more important indicator of subjective sleep quality in adolescence than is chronological age, most likely due to hormonal changes and psychological adjustment to the physical changes associated with the pubertal transition.

Sleep and Anabolic/Catabolic Hormonal Profile in Sedentary Middle-Aged Adults: The FIT-AGEING Study

Sleep quality plays an important role in the modulation of several aging markers. This influence could be explained by aging-induced hormonal changes. Indeed, poor sleep quality has been associated with the development of several endocrine-related health complications. This study examined the relationship of both subjective and objective sleep quantity and quality, with basal levels of selected plasma anabolic and catabolic hormones in sedentary middle-aged adults. A total of 74 volunteers (52.7% women; aged 53.7 ± 5.1) were recruited for this study. Subjective sleep quality was assessed by the Pittsburgh Sleep Quality Index (PSQI; higher scores indicate worse sleep quality), and objective sleep quality parameters (total sleep time [TST], wake after sleep onset [WASO], and sleep efficiency [SE]) were measured using a wrist-worn accelerometer. Basal levels of plasma dehydroepiandrosterone sulphate (DHEAS), total testosterone, sex hormone binding globulin (SHBG), somatotropin, and cortisol levels, were determined. Free testosterone was calculated from the total testosterone and SHBG levels. No associations of global PSQI score, TST, WASO, and SE with DHEAS, free testosterone, and somatotropin plasma levels were found, neither in men nor in women (all p ≥ 0.05). Global PSQI score was inversely related to cortisol plasma levels in women (p = 0.043). WASO was positively associated with cortisol plasma levels, while SE was negatively associated with cortisol plasma levels in women (all p ≤ 0.027). Sleep quality is not related to levels of plasma anabolic hormones, but to levels of catabolic hormones, in sedentary middle-aged adults. Therefore, these results suggest that potential changes in aging biomarkers associated with sleep disturbances, could be mediated by age-related changes in the catabolic endocrine system.

Effects of mindfulness-based stress reduction on adults with sleep disturbance: an updated systematic review and meta-analysis

ObjectiveMindfulness-based stress reduction (MBSR) is a meditation-based therapy originally recommended for stress management. However, it is currently used to alleviate sleep disturbances. Therefore, this contemporary systematic review aimed to elucidate...

Comparison of Subjective and Objective Sleep Quality in Subjects with and without Hyper-kyphosis

Comparison of Subjective and Objective Sleep Quality in Subjects with and without Hyper-kyphosis

Objective Sleep Quality and the Underlying Functional Neural Correlates Among Older Adults with Possible Mild Cognitive Impairment.

Poor sleep quality is common among older individuals with mild cognitive impairment (MCI) and may be a consequence of functional alterations in the brain; yet few studies have investigated the underlying neural correlates of actigraphy-measured sleep quality in this cohort. The objective of this study was to examine the relationship between brain networks and sleep quality measured by actigraphy. In this cross-sectional analysis, sleep efficiency and sleep fragmentation were estimated using Motionwatch8 (MW8) over a period of 14 days in 36 community-dwelling older adults with possible MCI aged 65-85 years. All 36 participants underwent resting-state functional magnetic resonance imaging (fMRI) scanning. Independent associations between network connectivity and MW8 measures of sleep quality were determined using general linear modeling via FSL. Networks examined included the somatosensory network (SMN), frontoparietal network (FPN), and default mode network (DMN). Across the 36 participants (mean age 71.8 years; SD = 5.2 years), mean Montreal Cognitive Assessment score was 22.5 (SD = 2.7) and Mini-Mental State Examination score was 28.3 (SD = 1.5). Mean sleep efficiency and fragmentation index was 80.1% (SD = 10.0) and 31.8 (SD = 10.4) respectively. Higher sleep fragmentation was significantly correlated with increased connectivity between the SMN and insula, the SMN and posterior cingulate, as well as FPN and primary motor area (FDR-corrected, p < 0.004). Functional connectivity between brain regions involved in attentional and somatosensory processes may be associated with disrupted sleep in older adults with MCI.

Association of hormone therapy and changes of objective sleep quality in women of late menopausal transition with sleep disorder: a preliminary study.

The aim of this study was to investigate changes in objective sleep quality with hormone therapy (HT) in women with late menopausal transition. Healthy midlife women with sleep difficulty who received HT were included. Those undergoing late menopausal transition were screened. Sleep patterns and self-reported questionnaires were collected before and 10 weeks after starting HT. Ten women who met the criteria (age, 50.1 ± 2.8 years) showed higher sleep efficiency and shorter wakefulness after sleep onset (WASO) 10 weeks after starting HT. However, no significant change was found in objective sleep quality after adjustment for multiple comparisons: sleep efficiency, 84.2 ± 7.7 versus 88.2% ± 4.7%, P = 0.037, adjusted P = 0.259; WASO, 59.0 ± 27.2 minutes versus 41.4 ± 17.4 minutes, P = 0.020, adjusted P = 0.140; average duration per awakening, 2.9 ± 1.0 minutes versus 2.2 ± 0.5 minutes, P = 0.033, adjusted P = 0.231. A better score of subjective sleep quality in the Pittsburgh Sleep Quality Index was observed 10 weeks after starting HT (2.0 ± 0.0 vs 1.2 ± 0.4, P = 0.006, adjusted P = 0.042), but sensitivity analysis did not show consistent results after adjustment for multiple comparisons (2.0 ± 0.0 vs 1.1 ± 0.4, P = 0.020, adjusted P = 0.140). Total scores of the Insomnia Severity Index and Menopause Rating Scale were better 10 weeks after starting HT (Insomnia Severity Index, 14.7 ± 3.0 vs 9.1 ± 3.8, P = 0.010; Menopause Rating Scale, 29.0 ± 5.2 vs 21.6 ± 3.0, P = 0.009) with consistent results in sensitivity analyses. There was no difference in the Epworth Sleepiness Scale before and after HT (7.2 ± 1.7 vs 8.6 ± 4.5, P = 0.309). The change in each objective sleep quality variable before and after HT showed strong positive or negative correlations with the change in only a few items in subjective sleep quality. Women in the late menopausal transition period showed higher sleep efficiency and shorter WASO after HT; however, multiple comparisons showed no statistically significant difference in objective sleep quality between before and after HT.

Variation in Gut Microbiota Composition is Associated with Sleep Quality and Cognitive Performance in Older Adults with Insomnia.

PurposeInsomnia, a chronic condition affecting 50% of older adults, is often accompanied by cognitive decline. The mechanism underlying this comorbidity is not fully understood. A growing literature suggests the importance of gut microbiota for brain function. We tested associations between sleep quality and cognitive performance with gut microbiota in older adults with insomnia.Patients and MethodsSeventy-two older adults with insomnia (age 73.2 ± 5.73 years, 56 females) provided stool samples for gut microbial sequencing. Microbiota profile was determined using the DADA2 bioinformatics pipeline. Cognition was assessed with the Cambridge Neuropsychological Test Automated Battery. Objective sleep quality was monitored by a two-week actigraphic recording, and participants completed the Insomnia Severity Index (ISI). We used partial canonical correspondence analysis (pCCA) to examine the relative contribution of insomnia, based on actigraphic sleep efficiency (SE) and ISI, and of cognitive status, based on the Multitasking test of Median Reaction Latency (MTTLMD) and the Spatial Working Memory Between Errors (SWMBE), to variance in microbiota composition. We used Pearson correlations to correlate insomnia and cognitive status parameters with microbiota amplicon sequence variants, genera, and families.ResultsThe pCCA revealed that sleep quality and cognitive performance explained a variation of 7.5–7.9% in gut microbiota composition in older adults with insomnia. Correlation analysis demonstrated that Lachnoclostridium (genus) correlates positively with SE (r=0.42; P=0.05) and negatively with MTTLMD (r=−0.29; P=0.03), whereas Blautia (genus) correlates negatively with MTTLMD (r=−0.31; P=0.01).ConclusionFindings demonstrate the associations of sleep quality and cognitive performance with variance in gut microbiota composition and with specific genus abundance in older adults with insomnia. Further studies should validate the findings, determine causal relationships, and evaluate potential interventions for the comorbidity of insomnia and cognitive impairment in older adults with insomnia.

The Influence of Scent on Sleep Quality

The use of scents in sleep medicine is gaining increasing attention since they have been shown to improve sleep quality. This randomized double-blinded crossover trial measured the extent to which a continuous nightly presentation of a synthetic jasmine scent combined with lavender oil and passionflower herb improves subjective and objective sleep quality. Thirty sensitive sleepers (ISI 7-14) who suffer from delayed sleep-onset and frequent sleep disturbances (2-3 per week) were monitored under four conditions in the sleep laboratory over four nights. The first night was for acclimation (baseline), and the other nights were randomized in a counterbalanced order (placebo rose scent, a high-dose of jasmine scent, or a low-dose relative to the essential oils). Alongside this, subjects were given standardized questionnaires to complete in the morning and evening. There was a significant improvement in sleep quality and total sleep time when using scents compared to baseline. Furthermore, both variants of jasmine decreased wake after sleep onset. The results also indicated that the application of scent on the T-shirt was well tolerated by all subjects. Overall, it was shown that the jasmine scent may positively affect sleep parameters, and moderators such as dosage, application method, and duration of the scent should be further investigated.

A Preliminary Study of the Effect of Mattress Temperature on the Subjective and Objective Sleep Quality of Healthy Young Adults

Objective: We evaluated the effects of microclimate temperature on the subjective and objective sleep quality of healthy young adults. For this purpose, we maintained a constant ambient temperature and manipulated the mattress temperature to change the microclimate.Methods: We enrolled 34 healthy young adults (12 males and 22 females; mean age: 24.06±2.70 years). Data from 26 individuals were analyzed (8 males and 18 females; mean age: 23.46±2.40 years). Nocturnal polysomnography (nPSG) was performed and self-reported questionnaires were completed at an ambient temperature of 27°C and mattress temperature of 28°C, 30°C, or 32°C.Results: The subjective sleep satisfaction was lower at a mattress temperature of 32°C than at 28°C. The subjective sleep latency was longer at 32°C than at 30°C. The number of respondents that selected sleep environment (including temperature) as the cause of sleep dissatisfaction was greater at higher temperatures. Participants felt that the mattress temperature was the least cool when they woke up at 32° than 30°C. Furthermore, they reported that the sleep latency at 32°C was longer than the other temperatures compared to usual sleep, and that they had more frequent awakenings at 32°C than at 28°C. The nPSG results showed that the proportion of rapid eye movement (REM) sleep was lower at 28°C than at 30°C.Conclusion: A high microclimate temperature caused by a high mattress temperature was associated with poor subjective sleep quality. Mattress temperature was also related to the objective proportion of REM sleep; however, the results are inconsistent with previous findings. Additional large-scale studies that evaluate a wider temperature range are required.

Effects of exercise intensity and frequency on improving cognitive performance in middle-aged and older adults with mild cognitive impairment: A pilot randomized controlled trial on the minimum physical activity recommendation from WHO.

Background: The World Health Organization physical activity guidelines recommend adults and older adults to accumulate at least 150–300 min of moderate or 75–150 min of vigorous aerobic-type physical activity weekly for health benefits including improvements of cognitive performance. However, the optimal exercise intensity and frequency for maximizing the cognitive benefits remain unclear. Purpose: We conducted a parallel, assessor-blinded, pilot randomized controlled trial to evaluate the effectiveness of different intensities and frequencies of the WHO-recommended minimal volume of aerobic-type physical activity on improving cognitive performance in middle-aged and older adults with mild cognitive impairment (MCI). Methods: Participants were randomly allocated to the stretching exercise control group (CON), once-a-week and thrice-a-week moderate-intensity walking groups (M1 and M3), and once-a-week and thrice-a-week vigorous-intensity walking groups (V1 and V3). Intervention duration was 12 weeks. The primary outcome was global cognitive performance assessed by the Hong Kong version of Montreal Cognitive Assessment. Secondary outcomes were self-report and objective cognitive performances, mental health, sleep quality, and cardiorespiratory fitness. Results: Thirty-seven participants completed the study (CON: n = 7, M1: n = 7, M3: n = 7, V1: n = 8, V3: n = 8). Participants in all four walking exercise groups demonstrated significant improvements in global cognitive performance assessed by the Hong Kong version of the Montreal Cognitive Assessment after the intervention when compared to CON (p < 0.001). The walking exercise interventions also significantly mitigated the anxiety severity (p < 0.005) and improved the cardiorespiratory fitness (p < 0.05) of the participants in the walking exercise groups. Conclusion: 150-min moderate- or 75-min vigorous-intensity walking exercise performed once- or thrice-weekly showed similar effects on improving cognitive performance in middle-aged and older adults with MCI. The 12-week walking exercise interventions also reduced anxiety severity and improved cardiorespiratory fitness of the participants. Clinical Trial Registration: clinicaltrials.gov, identifier NCT04515563

Subjective And Objective Cognitive Fatigue In Wildland Firefighting

Wildland firefighting requires continuous attention while exposed to long working hours and sub-optimal sleep. These stressors may induce cognitive fatigue, which poses a risk to worker safety due to reduced awareness. PURPOSE: This pilot investigation examined the effect of sleep and shift characteristics on variables related to cognitive fatigue. METHODS: A within-subject, observational study was conducted on 4 wildland firefighters (3 M, 1F) between July and August of the 2021 fire season. Cognitive fatigue was measured before and after shift, both subjectively, via 7-point scales (Samn-Perelli Fatigue Scale (SPS); Stanford Sleepiness Scale (SSS)), and objectively, via mean reaction time (RT) on the 3-minute psychomotor vigilance task. Sleep variables were measured subjectively via sleep log and objectively via wrist-worn actigraphy. Linear regression analyses were performed to test if shift or sleep variables predicted cognitive fatigue variables. RESULTS: All sleep and shift variables significantly predicted subjective fatigue and sleepiness. SPS was most significantly predicted by shift duration (R2 = .52, F(1, 49) = 52.75, p < .001) and subjective sleep quality (R2 = .24, F(1, 105) = 32.59, p < .001). SSS was most significantly predicted by subjective sleep quality (R2 = .32, F(1, 105) = 49.7, p < .001) and start time (R2 = .21, F(1, 87) = 23.75, p < .001). Mean RT was not significantly predicted by any sleep or shift variable. However, RT was significantly predicted by both subjective sleepiness (R2 = .34, F(1, 55) = 28.52, p < .001) and fatigue (R2 = .12, F(1, 55) = 7.73, p < .01). Mean RT was also non-significantly predicted by objective sleep quality (R2 = .10 F(1, 25) = 2.83, p = 0.105). CONCLUSIONS: Subjective cognitive fatigue measures were significantly predicted by sleep and shift characteristics. Neither sleep nor shift variables significantly predicted mean RT directly, however, RT was significantly predicted by subjective fatigue and sleepiness.

Effect Of Sleep And Shift Characteristics On Heart Rate Variability In Wildland Firefighters

Wildland firefighting requires demanding physical work while exposed to harsh working conditions, including long working hours, sub-optimal sleep, and psychological stress. These stressors may induce autonomic nervous system imbalance, which indicates potential risk to worker health and safety. PURPOSE: This pilot investigation examined the effect of sleep and shift characteristics on variables related to heart rate variability (HRV). METHODS: A within-subject, observational study was conducted on 4 wildland firefighters (3M, 1F) between July and August of the 2021 fire season. HRV was measured before and after shift using a chest-worn monitor (Polar H10 + Ignite Activity Tracker). Sleep variables were measured subjectively via sleep log and objectively via wrist-worn actigraphy. Subjective sleepiness and fatigue were also measured via 7-point scales (Stanford Sleepiness Scale; Samn-Perelli Fatigue Scale). Pearson correlation and linear regression analyses were performed to test if subjective, shift or sleep variables predicted HRV variables. RESULTS: Mean RR interval was positively related (r=.37) and significantly predicted by objective sleep quality (R2=.14, F(1, 59) = 9.24, p < .005), while also negatively related (r=-.19) and significantly predicted by subjective sleepiness (R2 = .03, F(1, 113) = 4.07, p < .05). rMSSD was negatively related (r=.-.23) and significantly predicted by wake-up time (R2 = .05, F(1, 75) = 4.06, p < .05). Surprisingly, total HF power was negatively related (r = .-26) and significantly predicted by start time (R2=.07, F(1, 66) = 4.92, p <.05), meanwhile LF/HF ratio was positively related (r=.27) and significantly predicted by start time (R2= .07, F(1, 66) = 5.06, p<.05). CONCLUSION: HRV measures were related to and significantly predicted by certain subjective, sleep, and schedule variables, thus warranting further investigation.

Effectiveness of a specific physical therapy program for Charcot-Marie-Tooth on sleep quality, pain perception, and nocturnal cramps: a pilot study.

IntroductionChronic pain, nocturnal cramps, and sleep alterations are prevalent symptoms and signals in Charcot-Marie-Tooth disease patients. Sleep and pain are bidirectionally related and physical therapy can improve the binomial sleep and pain/nocturnal cramps. Therefore, we hypothesized that the application of a specific physical therapy program for Charcot-Marie-Tooth disease would improve sleep quality, pain perception, and nocturnal cramps.Material and MethodsA non-randomized controlled study that included 9 Charcot-Marie-Tooth disease patients (intervention group - physical therapy program) and 8 controls (active control group - booklet on sleep hygiene). The intervention lasted 8 weeks, three sessions per week. The effects were evaluated ten days before (baseline) and ten days after the intervention (post). Our primary outcome was sleep quality (subjective and objective, assessed by Pittsburgh sleep quality index and actigraphy, respectively); and secondary outcomes were pain perception (brief pain inventory) and nocturnal cramps (self-report).ResultsThe program was able to improve the subjective sleep quality (p=0.005) and nocturnal cramps (p<0.001) but had no effect on actigraphy data (p>0.05) neither on pain perception (p>0.05).ConclusionOur initial hypothesis was partially corroborated: the improvement in subjective quality of sleep and nocturnal cramps is already beneficial for the health promotion of the volunteers in this study affected by the disease. Our findings may serve as a basis for future research to develop a program focused on the treatment of analgesia, which can improve pain perception and alter the objective quality of sleep.

Does Sleep Quality Influence Recovery Outcomes After Postconcussive Injury in Children and Adolescents?

To determine whether objective parameters of sleep quality differ throughout recovery between children and adolescents who experienced an early return to school (RTS) and those who had a delayed RTS or did not return at all during the study period. Sleep parameters reflective of sleep quality were evaluated in participants' natural sleeping habitat throughout 9 weeks postinjury. Ninety-four children and adolescents (aged 5-18 years) with diagnosed concussion. Prospective cohort. Participants followed RTS protocols. Actigraphy-derived estimates of total sleep time (TST), sleep efficiency (SE), wake after sleep onset (WASO), average arousal length (AAL), and number of arousals (NOAs) per hour were assessed. The length of time from injury until RTS was determined for each participant. Participants were categorized into an early RTS or delayed RTS group based on their time to RTS. Both TST and SE were significantly greater in the early RTS group. WASO duration, AAL, and NOAs were significantly greater in the delayed RTS group. Differences between RTS groups were most apparent during weeks 1 to 5 postinjury. Participants who returned to school earlier had significantly better objective sleep quality than participants who experienced a delayed RTS. This study provides evidence in support of a relationship between sleep quality and time to RTS in children and adolescents with concussion. Considering early monitoring of sleep, education regarding sleep hygiene, and access to age-appropriate sleep interventions may be helpful in pediatric concussion recovery.

131 Sleeping It Off - Are Hospital Wards Too Noisy to Allow Patient Recovery?

Abstract Aim Increased overnight noise levels are known to stimulate the release of multiple stress hormones and negatively impact upon objective and subjective sleep quality. Increasing levels of noise impairs physical and psychological recovery, and has been shown to slow wound healing, increase complication rates, and lengthen hospital admissions. Noise levels are therefore an important component of post-operative care and recovery. The purpose of this study is to document the actual noise levels experienced by patients overnight and analyse the sources of noise. Method Firstly, five-minute recordings were made during four separate hours throughout the night on two wards - one paediatric and one adult. Secondly, researchers described and categorised the sources of noise. Results The World Health Organisation (WHO) has recommended that average overnight noise levels in hospitals should not exceed 35 dB. The average recorded on the paediatric and elderly ward was 42.27 dB and 43.91 dB, with peak noise levels of 93.65 dB and 97.01 dB respectively. In every five-minute recording, there was at least one sound louder than 67 dB. Researchers identified multiple avoidable and non-avoidable causes. Conclusions The average noise level was significantly greater than the WHO recommendations. Every five-minute recording contained peak sounds of significance. Such noise levels have been linked to poor sleep, increased stress hormone release, delayed wound healing, and an increased post-operative recovery time. Many feasible solutions to address the avoidable causes of these sounds are identified. Addressing this issue is important for both medical and surgical units and is likely to improve patient outcomes.

Dark nighttime interventions and sleep quality in intensive care unit patients: A systematic review and meta‐analysis

AbstractBackgroundSleep disturbances resulting from adverse clinical and environmental conditions are associated with unfavourable outcomes in critically ill patients.AimTo collect evidence on the effect of dark nighttime interventions on sleep quality and daytime sleepiness in intensive care unit (ICU) patients.Study DesignThe study followed the Preferred Reporting Items for Systematic reviews and Meta‐Analyses recommendations. This is a systematic review and meta‐analysis of experimental and quasi‐experimental studies, developed with adult patients admitted to ICUs and submitted to measures such as environmental brightness reduction, eye mask or blue light‐blocking glass use at night. Outcomes were subjective or objective sleep quality and excessive daytime sleepiness. Search was carried out in the PubMed/MEDLINE, Cochrane Library, Embase, Virtual Health Library, Cumulative Index to Nursing and Allied Health Literature, Web of Science, and Scopus databases, using grey literature. Covidence software, Cochrane tools and Grading of Recommendations Assessment, Development and Evaluation were used, and a meta‐analysis was performed using RevMan software.ResultsThirteen articles were included in the systematic review and seven studies were included in the meta‐analysis. There were 3 trials with 175 participants regarding lighting reduction and environmental noise control versus the usual routine, 2 of these trials, with 96 patients, were compiled in meta‐analysis in which it was observed a significant statistical improvement in subjective sleep quality, mean difference (MD) of 11.89 points (0–100); 95% confidence interval (CI) 8.0–15.76, evidence set with moderate certainty, as well as this same intervention, reduced daytime sleepiness in 2 trials, 135 participants (standardized MD −0.63; 95% CI −0.98 to −0.28), with low certainty evidence. Eye masks versus usual routine, 2 trials, 126 participants, improved subjective sleep quality (MD of 10 points; 95% CI 7.97–12.03), with moderate certainty of evidence. Eye mask use combined with other therapies versus usual routine, 5 trials, 204 participants, improved subjective sleep quality in all studies, with low certainty of evidence. Objective sleep assessment was not improved with these interventions.ConclusionsThis review shows some benefits of nighttime interventions on subjective sleep quality and excessive sleepiness, however, there is an urgent need to conduct better and more robust studies in this field.Relevance to Clinical Practiceapplying measures such as lighting reduction and eye mask use significantly improves sleep quality.

The Effect of Light Therapy on Electroencephalographic Sleep in Sleep and Circadian Rhythm Disorders: A Scoping Review.

Light therapy is used to treat sleep and circadian rhythm disorders, yet there are limited studies on whether light therapy impacts electroencephalographic (EEG) activity during sleep. Therefore, we aimed to provide an overview of research studies that examined the effects of light therapy on sleep macro- and micro-architecture in populations with sleep and circadian rhythm disorders. We searched for randomized controlled trials that used light therapy and included EEG sleep measures using MEDLINE, PubMed, CINAHL, PsycINFO and Cochrane Central Register of Controlled Trials databases. Five articles met the inclusion criteria of patients with either insomnia or delayed sleep–wake phase disorder (DSWPD). These trials reported sleep macro-architecture outcomes using EEG or polysomnography. Three insomnia trials showed no effect of the timing or intensity of light therapy on total sleep time, wake after sleep onset, sleep efficiency and sleep stage duration compared to controls. Only one insomnia trial reported significantly higher sleep efficiency after evening light therapy (>4000 lx between 21:00–23:00 h) compared with afternoon light therapy (>4000 lx between 15:00–17:00 h). In the only DSWPD trial, six multiple sleep latency tests were conducted across the day (09:00 and 19:00 h) and bright light (2500 lx) significantly lengthened sleep latency in the morning (09:00 and 11:00 h) compared to control light (300 lx). None of the five trials reported any sleep micro-architecture measures. Overall, there was limited research about the effect of light therapy on EEG sleep measures, and studies were confined to patients with insomnia and DSWPD only. More research is needed to better understand whether lighting interventions in clinical populations affect sleep macro- and micro-architecture and objective sleep timing and quality.

Relationship between gastroesophageal reflux disease and objective sleep quality.

To objectively characterize (1) the relationship between gastroesophageal reflux disease (GERD) and sleep quality, and (2) the influence of sleep position on this relationship, using in-laboratory polysomnography. We retrospectively analyzed first-night diagnostic in-laboratory polysomnography data for 3411 patients (median age 55 years; 48% male). Medication use and medical condition data were obtained through self-reported questionnaires. Associations between sleep quality and the presence of GERD, and the influence of sleep position on these associations, were analyzed using multivariable linear regression models. After adjusting for age, sex, body mass index, and relevant comorbidities, GERD was associated with a 3.0% decrease in sleep efficiency, 8.8-minute increase in wake after sleep onset, 24.4-minute increase in rapid eye movement (REM) latency, 13.4-minute decrease in total sleep time, 1.4% decrease in %REM sleep, and 1.5% increase in %N3 sleep. Having both GERD and the majority of sleep on the right side was associated with an 8.6% decrease in sleep efficiency, 27.5-minute increase in wake after sleep onset, 35.6-minute decrease in total sleep time, 2.1% decrease in %REM sleep, and 3.5% increase in %N3 sleep. Having both GERD and the majority of sleep on the left side was associated with an 8.7-minute increase in sleep onset latency. GERD is associated with an impairment in objective sleep quality. These associations were more pronounced in right-sided sleep and mostly ameliorated in left-sided sleep. Physicians should recognize the potential for poor sleep quality in patients with GERD and the effect of body position on this relationship. Gurges P, Murray BJ, Boulos MI. Relationship between gastroesophageal reflux disease and objective sleep quality. J Clin Sleep Med. 2022;18(12):2731-2738.

Food-derived antioxidant ergothioneine improves sleep difficulties in humans

• Volunteers with reported high anxiety and sleep complaints daily took ergothioneine (EGT) for 4 weeks. • A questionnaire survey showed that EGT significantly ameliorate sleeping difficulties. • Electroencephalograph measurements showed that ingesting EGT resulted in a significant improvement in objective sleep quality. • Metabolome analysis suggested that EGT reduces consumption of antioxidant substances while enhancing lipid metabolism. Sleep disorders interfere with daily life and are associated with the development of various diseases. Here, we evaluated the effect of orally ingested ergothioneine (EGT) on improving sleep quality. We conducted a randomized, placebo-controlled, double-blind, parallel-group comparison study. A 20 mg EGT or placebo capsule was ingested daily for 4 weeks by volunteers with reported high anxiety and sleep complaints. A survey showed that EGT significantly ameliorates sleeping difficulties. Electroencephalograph measurements showed that EGT intake increases the N2 stage, while decreasing the N1 stage in non-REM sleep and the frequency of waking after sleep onset. Serum metabolome analysis suggested that EGT reduces serum glutamate as well as the consumption of antioxidant and anti-inflammatory substances while enhancing lipid metabolism. Molecular targeting assays revealed that EGT inhibits histamine N-methyltransferase and aldehyde dehydrogenase activity and binding to α3β4 nicotinic acetylcholine receptor. Hence, EGT may improve sleep difficulties via multiple mechanisms of action.