Circadian Rhythm and Sleep Disruption: Causes, Metabolic Consequences, and Countermeasures

Sleep problems and their predictors in community-dwelling older adults with diabetes in India: Evidence from the Longitudinal Ageing Study in India

Objectives

To ascertain the prevalence and predictors of sleep disorders and poor sleep quality among older adults with Diabetes (DM) in India, and to assess the relationship between sleep quality and DM.

Methods

Data was utilized from the nationally representative Longitudinal Ageing Study in India (Wave-1, 2017-18), with a total sample of 66606 older adults (≥45 years) selected for the study. Sleep problems and sleep quality score were assessed using an adaptation based on the Jenkins Sleep Scale. Multivariate linear and logistic regressions were conducted to determine the effect of sociodemographic and clinical factors on sleep quality. Mediation analysis (Karlson-Holm-Breen) was done to assess the direct and indirect effects of independent variables on the sleep quality scores. Further, Propensity score matching (PSM) was done to assess the impact of diabetes on sleep problems.

Results

The prevalence of DM was 12.34% (n = 8564, 95% CI: 11.54, 13.20) among whom 24.38% (95% CI: 21.38, 27.65) reported sleep problems. On adjusted analysis, sleep problems were significantly associated with increasing education, higher wealth quintile, lack of physical activity, and multimorbidity. Mediation analysis showed adherence to anti-diabetes medication improved sleep quality (aB = -0.28 (95% CI: -0.54, -0.02)), while comorbidities worsened sleep quality (aB = 0.79 (95% CI: 0.67, 0.92)). Analysis from PSM indicated that DM was associated with a 6.2% higher chance of sleep problems.

Conclusions

Poor sleep quality is present in nearly one in four individuals diagnosed with DM in India and linked with certain adverse social determinants. Focused interventions to improve assessment and treatment of sleep problems in resource-limited primary care settings require prioritization.

Does sunlight exposure predict next-night sleep? A daily diary study among U.S. adults

Poor sleep is becoming increasingly prevalent and is associated with adverse health outcomes. Sunlight exposure may improve sleep by regulating circadian rhythms, increasing vitamin D, and influencing melatonin production. However, research on the sunlight-sleep association is limited, especially outside of cross-sectional designs. This study examined associations between daily self-reported sunlight exposure and next-night sleep quality in 103 adults for up to 70 days. The timing of sunlight exposure predicted next-night sleep quality. Specifically, morning sunlight exposure, relative to no sunlight, predicted better sleep quality based on responses to the brief Pittsburg Sleep Quality Index. Duration of sunlight exposure was generally not associated with sleep quality. Morning sunlight may regulate circadian rhythms, subsequently improving sleep. Findings have potential implications for sleep interventions and daylight savings time policies. Future research should test whether morning sunlight exposure can enhance the effectiveness of sleep interventions.

Overlapping Central Clock Network Circuitry Regulates Circadian Feeding and Activity Rhythms in Drosophila

The circadian system coordinates multiple behavioral outputs to ensure proper temporal organization. Timing information underlying circadian regulation of behavior depends on a molecular circadian clock that operates within clock neurons in the brain. In Drosophila and other organisms, clock neurons can be divided into several molecularly and functionally discrete subpopulations that form an interconnected central clock network. It is unknown how circadian signals are coherently generated by the clock network and transmitted across output circuits that connect clock cells to downstream neurons that regulate behavior. Here, we have exhaustively investigated the contribution of clock neuron subsets to the control of two prominent behavioral outputs in Drosophila: locomotor activity and feeding. We have used cell-specific manipulations to eliminate molecular clock function or induce electrical silencing either broadly throughout the clock network or in specific subpopulations. We find that clock cell manipulations produce similar changes in locomotor activity and feeding, suggesting that overlapping central clock circuitry regulates these distinct behavioral outputs. Interestingly, the magnitude and nature of the effects depend on the clock subset targeted. Lateral clock neuron manipulations profoundly degrade the rhythmicity of feeding and activity. In contrast, dorsal clock neuron manipulations only subtly affect rhythmicity but produce pronounced changes in the distribution of activity and feeding across the day. These experiments expand our knowledge of clock regulation of activity rhythms and offer the first extensive characterization of central clock control of feeding rhythms. Despite similar effects of central clock cell disruptions on activity and feeding, we find that manipulations that prevent functional signaling in an identified output circuit preferentially degrade locomotor activity rhythms, leaving feeding rhythms relatively intact. This demonstrates that activity and feeding are indeed dissociable behaviors, and furthermore suggests that differential circadian control of these behaviors diverges in output circuits downstream of the clock network.

Hydrogen as an innovative nootropic in health and disease

Molecular hydrogen (H2, dihydrogen) is an antioxidant and signaling molecule with potent antioxidative, antiapoptotic, and anti-inflammatory properties. Despite the growing interest in H2 as a potential therapeutic agent, the evidence regarding its potential as a nootropic remains limited. Only a handful of studies on the human population have evaluated its effects, although there are suggestive indications of its efficacy. The present paper overviews H2's potential as a novel agent for improving cognitive functions in health and disease contexts, highlighting its mechanisms of action and areas for further investigation. Current evidence suggests that H2 improves executive function, alertness and memory in several clinical trials, from healthy young and elderly individuals to individuals with altered circadian rhythms, neurodegenerative disorders, and cancer. Further investigations are needed to confirm the potential positive effects of dihydrogen as a nootropic agent in both health and disease.

Efferent pathways from the suprachiasmatic nucleus to the horizontal limbs of diagonal band promote NREM sleep during the dark phase in mice

The regulation of circadian rhythms and the sleep-wake states involves in multiple neural circuits. The suprachiasmatic nucleus (SCN) is a circadian pacemaker that controls the rhythmic oscillation of mammalian behaviors. The basal forebrain (BF) is a critical brain region of sleep-wake regulation, which is the downstream of the SCN. Retrograde tracing of cholera toxin subunit B showed a direct projection from the SCN to the horizontal limbs of diagonal band (HDB), a subregion of the BF. However, the underlying function of the SCN-HDB pathway remains poorly understood. Herein, activation of this pathway significantly increased non-rapid eye movement (NREM) sleep during the dark phase by using optogenetic recordings. Moreover, activation of this pathway significantly induced NREM sleep during the dark phase for first 4 h by using chemogenetic methods. Taken together, these findings reveal that the SCN-HDB pathway participates in NREM sleep regulation and provides direct evidence of a novel SCN-related pathway involved in sleep-wake states regulation.

The impact of REM sleep loss on human brain connectivity

Brain function is vulnerable to the consequences of inadequate sleep, an adverse trend that is increasingly prevalent. The REM sleep phase has been implicated in coordinating various brain structures and is hypothesized to have potential links to brain variability. However, traditional imaging research have encountered challenges in attributing specific brain region activity to REM sleep, remained understudied at the whole-brain connectivity level. Through the spilt-night paradigm, distinct patterns of REM sleep phases were observed among the full-night sleep group (n = 36), the early-night deprivation group (n = 41), and the late-night deprivation group (n = 36). We employed connectome-based predictive modeling (CPM) to delineate the effects of REM sleep deprivation on the functional connectivity of the brain (REM connectome) during its resting state. The REM sleep-brain connectome was characterized by stronger connectivity within the default mode network (DMN) and between the DMN and visual networks, while fewer predictive edges were observed. Notably, connections such as those between the cingulo-opercular network (CON) and the auditory network, as well as between the subcortex and visual networks, also made significant contributions. These findings elucidate the neural signatures of REM sleep loss and reveal common connectivity patterns across individuals, validated at the group level.

Daytime napping and the risk of gastric cancer: the JACC Study

BACKGROUND

Gastric cancer is a major cause of morbidity and mortality in Japan and worldwide. Emerging literature has suggested unfavorable health outcomes associated with daytime napping. Herein, we aimed to investigate the association between daytime napping and the risk of gastric cancer among Japanese people.

METHODS

This prospective cohort study included 49,037 participants, aged 40-79 years, from the Japan Collaborative Cohort Study (JACC Study). Participants with positive cancer history and those who reported night or rotational shift work were excluded. Cox proportional hazard models were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) of incident gastric cancer among daytime nappers.

RESULTS

Within 650,040 person-years (median = 13.7 years) of follow-up, 1,164 participants developed gastric cancer. Daytime napping was associated with the increased risk of gastric cancer in the multivariable-adjusted model: HR (95% CI) = 1.14 (1.01, 1.29). The excess risk did not significantly differ across sexes, age groups (<65 and ≥65 years), and employment status (employed and unemployed) (p-interactions > 0.40). However, sleep duration modified this effect: HRs (95% CIs) = 1.66 (1.23, 2.23) in sleep duration ≤6 h/night versus 1.06 (0.93, 1.21) in sleep duration >6 h/night (p-interaction = 0.006).

CONCLUSION

Daytime napping was associated with increased gastric cancer risk, especially among those who reported short sleep duration.

The Impact of Sleep on Haematological Parameters in Firefighters

Sleep is a vital process that impacts biological functions such as cell renewal, bone regeneration, and immune system support. Disrupted sleep can interrupt erythropoiesis, leading to fewer red blood cells, reduced haemoglobin concentration, and decreased haematocrit levels, potentially contributing to haematological disorders. This is particularly concerning for shift workers for example firefighters. While previous studies have explored sleep's adverse effects on various professions, research specific to firefighters is limited. This study investigates the relationship between sleep quality and haematological parameters among firefighters in Northeast Portugal. From a sample of 201 firefighters, variations in red blood cells, haemoglobin, and haematocrit values were linked to sleep quality. The study utilised non-parametric tests (Wilcoxon-Mann-Whitney, Spearman's correlation) to explore the connection between sleep quality and haematological profile. The impact of covariates on haematological parameters was assessed using non-parametric ANCOVA (Quade's). A multiple regression analysis was employed to further understand how sleep quality and various confounding variables impact haematological levels. Findings suggest a negative link between sleep quality and haematological levels, meaning that as sleep quality deteriorates, there is a tendency for haematological levels to decrease, as indicated by Spearman's correlation (rRBC = -0.157, pRBC = 0.026; rHb = -0.158, pHb = 0.025; rHCT = -0.175, pHCT = 0.013). As observed in scientific literature, the correlation found suggests a possible inhibition of erythropoiesis, the process responsible for red blood cell production. Despite firefighters presenting a haematological profile within the reference range (RBC: 5.1 × 106/mm3 (SD ± 0.4), Hb: 15.6 g/dL (SD ± 1.3), 47% (SD ± 1.0), there is already an observable trend towards lower levels. The analysis of co-variables did not reveal a significant impact of sleep quality on haematological levels. In conclusion, this study underscores the importance of sleep quality in determining haematological parameters among firefighters. Future research should investigate the underlying mechanisms and long-term implications of poor sleep quality on firefighter health. Exploring interventions to enhance sleep quality is vital for evidence-based strategies promoting firefighter well-being.

Understanding perceptions about the health effects of night working and the barriers and enablers to taking part in nutritional research: A qualitative study among night workers in England

Working at night is associated with adverse cardiometabolic health outcomes. However, there are a lack of nutritional intervention studies conducted amongst night workers, subsequently contributing to a lack of evidence-based guidelines for night workers. The aim of The Eating on the Night Shift study was to understand how night shift workers view working at night in relation to nutritional health and wellbeing, the barriers and enablers to participate in research and what kind of guidance would be useful to them. Semi-structured qualitative interviews were conducted with a convenience sample (n = 18) of night workers based in England. The interview covered experiences of working night shifts, perceptions about night work and their health, and perceptions of and likely engagement with nutritional research. Interviews were audio recorded and transcribed verbatim. Transcripts were coded using an inductive thematic analysis approach. Of the final sample 13 were female (72%), 39% worked a rotating shift pattern and 78% had worked night shifts for 1 year or more. Four overarching themes were identified: (1) the consequences of night work on health and wellbeing, (2) eating at night means a less healthy diet, (3) working at night has wider knock-on effects on aspects of lifestyle and wellbeing and (4) nutritional research is perceived as important, but there are barriers to participation. Night workers are aware that working at night can negatively impact their diet as well as their health. Nutritional researchers need to engage with night workers when considering intervention design and implementation as well as in the development of any resultant evidence-based guidance to ensure its relevance.

Circadian rhythm analysis using wearable-based accelerometry as a digital biomarker of aging and healthspan

Recognizing the pivotal role of circadian rhythm in the human aging process and its scalability through wearables, we introduce CosinorAge, a digital biomarker of aging developed from wearable-derived circadian rhythmicity from 80,000 midlife and older adults in the UK and US. A one-year increase in CosinorAge corresponded to 8-12% higher all-cause and cause-specific mortality risks and 3-14% increased prospective incidences of age-related diseases. CosinorAge also captured a non-linear decline in resilience and physical functioning, evidenced by an 8-33% reduction in self-rated health and a 3-23% decline in health-related quality of life score, adjusting for covariates and multiple testing. The associations were robust in sensitivity analyses and external validation using an independent cohort from a disparate geographical region using a different wearable device. Moreover, we illustrated a heterogeneous impact of circadian parameters associated with biological aging, with young (<45 years) and fast agers experiencing a substantially delayed acrophase with a 25-minute difference in peak timing compared to slow agers, diminishing to a 7-minute difference in older adults (>65 years). We demonstrated a significant enhancement in the predictive performance when integrating circadian rhythmicity in the estimation of biological aging over physical activity. Our findings underscore CosinorAge's potential as a scalable, economic, and digital solution for promoting healthy longevity, elucidating the critical and multifaceted circadian rhythmicity in aging processes. Consequently, our research contributes to advancing preventive measures in digital medicine.

Total Joint Arthroplasty and Sleep: The State of the Evidence

Background

As the number of total hip and knee arthroplasties (TJA) performed increases, there is heightened interest in perioperative optimization to improve outcomes. Sleep is perhaps one of the least understood perioperative factors that affects TJA outcomes. The purpose of this article is to review the current body of knowledge regarding sleep and TJA and the tools available to optimize sleep perioperatively.

Methods

A manual search was performed using PubMed for articles with information about sleep in the perioperative period. Articles were selected that examined: sleep and pain in the perioperative period; the effect of surgery on sleep postoperatively; the relationship between sleep and TJA outcomes; risk factors for perioperative sleep disturbance; the effect of anesthesia on sleep; and the efficacy of interventions to optimize sleep perioperatively.

Results

Sleep and pain are intimately associated; poor sleep is associated with increased pain sensitivity. Enhanced sleep is associated with improved surgical outcomes, although transient sleep disturbances are normal postoperatively. Risk factors for perioperative sleep disturbance include increasing age, pre-existing sleep disorders, medical comorbidities, and type of anesthesia used. Interventions to improve sleep include optimizing medical comorbidities preoperatively, increasing sleep time perioperatively, appropriating sleep hygiene, using cognitive behavioral therapy, utilizing meditation and mindfulness interventions, and using pharmacologic sleep aids.

Conclusions

Sleep is one of many factors that affect TJA. As we better understand the interplay between sleep, risk factors for suboptimal sleep, and interventions that can be used to optimize sleep, we will be able to provide better care and improved outcomes for patients.

Exploring the Role of Circadian Rhythms in Sleep and Recovery: A Review Article

Sleep is essential for every living organism. Humans spend about one-third of their lives sleeping. Sleep has been studied extensively, and the role of sleep in psychological, mental, and physical well-being is established to be the best. The rhythm of the brain between wakefulness and sleep is called the circadian rhythm, which is mainly controlled by melatonin and the pineal gland. The imbalance of this rhythm can lead to devastating effects on health. Vigorous workouts close to bedtime can interfere with falling asleep. Meal timing and composition can significantly affect sleep quality. It is advised to avoid large meals, caffeine, and alcohol before bedtime. Heavy meals close to bedtime can lead to poor sleep and hormone disruption. By following these guidelines enumerated in the article, individuals can improve sleep quality and overall health. Sleep cycles, especially rapid eye movement sleep, have a profound influence on mental and physical health. Adhering to recommended sleep practices enhances bodily restoration, fortifies the immune system, and upholds metabolic equilibrium. Sleep hygiene aligned with circadian rhythms is crucial for disease prevention and well-being. Healthcare professionals should prioritize sleep optimization strategies for patient care and public health.

Effects of Early and Late Time-Restricted Feeding on Parameters of Metabolic Health: An Explorative Literature Assessment

Chrono-nutrition (meal timing) aligns food consumption with one's circadian rhythm. The first meal (e.g., breakfast) likely promotes synchronization of peripheral circadian clocks, thereby supporting metabolic health. Time-restricted feeding (TRF) has been shown to reduce body weight (BW) and/or improve cardiovascular biomarkers. In this explorative literature assessment, 13 TRF randomized controlled trials (RCTs) were selected from PubMed and Scopus to evaluate the effects of early (eTRF: first meal before 10:30 a.m.) and late TRF (lTRF: first meal after 11:30 a.m.) on parameters of metabolic health. Although distinct variations in study design were evident between reports, TRF consistently decreased energy intake (EI) and BW, and improved insulin resistance as well as systolic blood pressure. eTRF seemed to have a greater beneficial effect than lTRF on insulin resistance (HOMA-IR). Importantly, most studies did not appear to consider chronotype in their evaluation, which may have underestimated TRF effects. TRF intervention may be a promising approach for risk reduction of human metabolic diseases. To conclusively determine benefits of TRF and identify clear differences between eTRF and lTRF, future studies should be longer-term (≥8 weeks) with well-defined (differences in) feeding windows, include participants chronotypically matching the intervention, and compare outcomes to those of control groups without any dietary limitations.

The mediating effect of sleep duration on metabolic syndrome severity in adults: a structural equation modeling approach

BACKGROUND

Metabolic syndrome (MetS) is associated to sleep duration. It is crucial to identify factors that disrupt sleep regulation. The study aimed to assess the indirect effect of risk factors related to MetS severity through sleep duration by utilizing a structural equation model (SEM).

METHODS

The study involving 3,935 adults from the baseline data of the Ravansar Non-Communicable Disease (RaNCD) cohort study. MetS severity scores were the outcome variables. SEM was employed to explore the relationships, utilizing IBM SPSS and AMOS version 23.

RESULTS

The mean MetS severity score was higher in women compared to men (0.25 vs. 0.16, P = 0.003). In men, socioeconomic status (SES) has a positive direct effect (β = 0.048) and a negative indirect effect (β=-0.006) on MetS severity. Increased physical activity is directly (β=-0.036) and indirectly (β=-0.093) associated with reducing MetS severity. Nap duration is directly linked to an increase (β = 0.072) but has an indirect effect (β=-0.008) in decreasing MetS severity. In women, SES has a direct (β=-0.020) and indirect (β=-0.001) inverse relationship with MetS severity. Increased physical activity is directly (β=-0.048) and indirectly (β=-0.036) associated with decreasing MetS severity in women. Nap duration is directly associated with an increase in MetS severity (β=-0.018) but indirectly contributes to its reduction (β=-0.002). Sleep duration not only directly affects MetS severity but is also influenced by age, SES, physical activity, obesity and nap duration.

CONCLUSION

Physical activity, SES, and nap duration directly and indirectly effect the MetS severity. Sleep duration was recognized as a mediating variable that supports the indirect effects.

Association of sleep fragmentation with general and abdominal obesity: a population-based longitudinal study

OBJECTIVE

To evaluate the causal relationship between sleep fragmentation (SF) parameters with general and abdominal obesity in free-living conditions.

METHODS

SF parameters were assessed by ActiGraph accelerometers for 7 consecutive days. Obesity was measured at baseline and 1-year follow-up with InBody S10 body composition analyzer.

RESULTS

At baseline, the mean age of the study population was 18.7 years old (SD = 0.9) and 139 (35.7%) were male. Each 1-unit increase of baseline sleep fragmentation index (SFI) was associated with 0.08 kg/m2-increase of body mass index (BMI) (95% CI: 0.03, 0.14), 0.20%-increase of percentage of body fat (PBF) (95% CI: 0.07, 0.32), 0.15 kg-increase of fat mass (FM) (95% CI: 0.03, 0.27), 0.15 cm-increase of waist circumference (WC) (95% CI: 0.03, 0.26) and 0.91 cm2-increase of visceral fat area (VFA) (95% CI: 0.36, 1.46) at the 1-year follow-up. In addition, each 1-unit increase of baseline SFI was associated with 15% increased risk of general obesity (OR = 1.15, 95% CI = 1.04-1.28; p = 0.006) and 7% increased risk of abdominal obesity (OR = 1.07, 95% CI = 1.01-1.13; p = 0.021) in the following year.

CONCLUSIONS

Fragmented sleep is independently associated with an increased risk of both general and abdominal obesity. The result highlights SF as a modifiable risk factor for the prevention and treatment of obesity.

Unveiling Coronasomnia: Pandemic Stress and Sleep Problems During the COVID-19 Outbreak

The COVID-19 pandemic posed an unprecedented challenge to public well-being, necessitating an examination of its health impact. This review discusses the relationship between pandemic-induced stressors and individual sleep patterns and quality. The pandemic stressors include lockdown or physical distancing measures, direct virus exposure, and the dissemination of misinformation and disinformation. The pandemic led to delayed sleep-wake cycles, except for healthcare professionals, and worsened sleep quality. The prevalence of insomnia was higher for women due to pre-existing conditions and susceptibility stressors such as lockdown stress and family responsibilities. Healthcare professionals, who experienced worsened work conditions during the pandemic, reported higher rates of insomnia and sleep difficulties due to infection anxiety and post-traumatic stress from direct virus exposure. For the general population, stress stemmed from social isolation under lockdown and overwhelming false information available online, resulting in sleep problems. Taken together, the findings highlight the importance of promoting social interactions, providing psychological support services, and caution in navigating health information. In summary, this review underscores the need for individual- and group-centered approaches in ongoing research and interventions to address pandemic-related stress and sleep issues during COVID-19.

Unfavorable Mealtime, Meal Skipping, and Shiftwork Are Associated with Circadian Syndrome in Adults Participating in NHANES 2005-2016

The concept of Circadian Syndrome (CircS) aims to emphasize the circadian disruptions underlying cardiometabolic conditions. Meal timing and shiftwork may disrupt circadian rhythms, increasing cardiometabolic risk. This study aimed to assess the associations of meal timing, meal skipping, and shiftwork with CircS in US adults and explore effect modifications by sociodemographic and lifestyle factors. CircS was defined using Metabolic Syndrome components in addition to short sleep and depression symptoms. Data from 10,486 participants of the National Health and Nutrition Examination Survey 2005-2016 were analyzed cross-sectionally. Mealtime was assessed by calculating the midpoint of intake between breakfast and dinner and dichotomizing it into favorable mealtime (between 12:30 and 13:15) and unfavorable mealtime using a data-driven approach. Meal skippers were categorized separately. Participants working evening, night, or rotating shifts were classified as shift workers. In the multivariable logistic regression analysis, an unfavorable mealtime, meal skipping, and shiftwork were associated with a higher likelihood of CircS (OR = 1.24; 95%CI 1.07-1.44, OR = 1.39; 95%CI 1.16-1.67, and OR = 1.37; 95%CI 1.01-1.87, respectively). Subgroup analyses revealed no significant interactions between meal timing, meal skipping, or shiftwork and socioeconomic status or lifestyle regarding CircS. These findings highlight the importance of aligning mealtimes with circadian rhythms for improved circadian health.

Association between Sleep Duration, Social Jetlag, and the Metabolic Syndrome by Shift Works

Lifestyle factors, including sleep characteristics, have been implicated in the development of metabolic syndrome, particularly among shift workers. This study aimed to explore the relationship between shift work, sleep duration, social jetlag, and the risk of metabolic syndrome among U.S. workers and the moderating effect of sleep duration and social jetlag on this relationship. Data from the National Health and Nutrition Examination Survey (NHANES) in 2017-2020 March were analyzed. Poisson regression models were employed to examine associations. Among 4136 U.S. workers, 53.3% had metabolic syndrome, with a higher proportion of shift workers (63.8% vs. 56.7%, p = 0.001) and those sleeping less than 6 h or more than 9 h per week (22.3% vs. 19.1%, p = 0.044) in the affected group. Shift workers were initially found to have an increased risk of metabolic syndrome (Coef. = 0.03, 95% CI: 0.02, 0.16); however, this association was mitigated when accounting for the interaction with social jetlag. Specifically, 1 to <2 h of social jetlag interacted significantly, increasing metabolic risk (Coef. = 0.15, 95% CI: 0.09, 0.22), whereas 1 to <2 h alone showed a protective effect (Coef. = -0.11, 95% CI: -0.17, -0.06). These findings suggest that optimizing sleep schedules and addressing social jetlag may be crucial in mitigating metabolic syndrome risks among shift workers.

Associations between multiple sleep dimensions and suicide and non-suicidal self-injury: a cross-sectional study of 3828 Chinese young people

PURPOSE

Suicide and non-suicidal self-injury (NSSI) are preventable concerns in young people. Suicidal ideation (SI), suicidal plans (SP) and suicidal attempt (SA) are closely related to death. Sleep problems are known risk factors for suicide and NSSI. This study aimed to explore the relationship between sleep, suicidality and NSSI.

METHODS

Participants were 3,828 middle school and college students aged 11-23 years from urban and rural areas of Henan Province. Sleep, suicidal phenomena and NSSI were assessed by applying self-reported questionnaires. Chi-squared tests were utilized to demonstrate the demographic data and sleep variables. The correlation between sleep, suicidality and NSSI were explored by using binary logistic regression, while adjusting socio-demographic characteristics with multivariate models.

RESULTS

Sleep variables except mid-sleep time were related to suicidal phenomena (P < 0.05). Greater social jet lag (SJL) [≥ 2 h (h)] was associated with increased risk of SI [Odds ratios (OR) = 1.72, 95% confidence intervals (CI):1.40-2.11], SP (OR = 2.10, 95%CI:1.59-2.79) and SA (OR = 1.50, 95%CI:1.00-2.26). Non-only child participants with SJL (≥ 2 h) had significantly increased odds of SI (OR = 1.75, 95%CI: 1.41-2.18) and SP (OR = 2.25, 95%CI: 1.66-3.05). Eveningness chronotype had the strongest correlation with SI (OR = 3.87, 95%CI:2.78-5.38), SP (OR = 4.72, 95%CI:2.97-7.50), SA (OR = 6.69, 95%CI:3.08-14.52) and NSSI (OR = 1.39, 95%CI:1.02-1.90).

CONCLUSION

Overlong or short sleep duration, SJL, eveningness chronotype and other sleep abnormalities (e.g., daytime dysfunction, low sleep efficiency) were associated with a higher prevalence of SI, SP and SA. Additionally, eveningness was significantly correlated with NSSI among young people. These findings suggested the importance of assessing and intervening in sleep habits to prevent suicide and NSSI in young people.

Association of sleep traits with risk of hypertensive disorders of pregnancy: a mendelian randomization study

BACKGROUND

Unhealthy sleep patterns are common during pregnancy and have been associated with an increased risk of developing hypertensive disorders of pregnancy (HDPs) in observational studies. However, the causality underlying these associations remains uncertain. This study aimed to evaluate the potential causal association between seven sleep traits and the risk of HDPs using a two-sample Mendelian randomization study.

METHODS

Genome-wide association study (GWAS) summary statistics were obtained from the FinnGen consortium, UK Biobank, and other prominent consortia, with a focus on individuals of European ancestry. The primary analysis utilized an inverse-variance-weighted MR approach supplemented by sensitivity analyses to mitigate potential biases introduced by pleiotropy. Furthermore, a two-step MR framework was employed for mediation analyses.

RESULTS

The data analyzed included 200 000-500 000 individuals for each sleep trait, along with approximately 15 000 cases of HDPs. Genetically predicted excessive daytime sleepiness (EDS) exhibited a significant association with an increased risk of HDPs [odds ratio (OR) 2.96, 95% confidence interval (95% CI) 1.40-6.26], and the specific subtype of preeclampsia/eclampsia (OR 2.97, 95% CI 1.06-8.3). Similarly, genetically predicted obstructive sleep apnea (OSA) was associated with a higher risk of HDPs (OR 1.27, 95% CI 1.09-1.47). Sensitivity analysis validated the robustness of these associations. Mediation analysis showed that BMI mediated approximately 25% of the association between EDS and HDPs, while mediating up to approximately 60% of the association between OSA and the outcomes. No statistically significant associations were observed between other genetically predicted sleep traits, such as chronotype, daytime napping, sleep duration, insomnia, snoring, and the risk of HDPs.

CONCLUSION

Our findings suggest a causal association between two sleep disorders, EDS and OSA, and the risk of HDPs, with BMI acting as a crucial mediator. EDS and OSA demonstrate promise as potentially preventable risk factors for HDPs, and targeting BMI may represent an alternative treatment strategy to mitigate the adverse impact of sleep disorders.

Nutraceutical blends predict enhanced health via microbiota reshaping improving cytokines and life quality: a Brazilian double-blind randomized trial

Nutraceutical interventions supporting microbiota and eliciting clinical improvements in metabolic diseases have grown significantly. Chronic stress, gut dysbiosis, and metainflammation have emerged as key factors intertwined with sleep disorders, consequently exacerbating the decline in quality of life. This study aimed to assess the effects of two nutraceutical formulations containing prebiotics (fructooligosaccharides (FOS), galactooligosaccharides (GOS), yeast β-glucans), minerals (Mg, Se, Zn), and the herbal medicine Silybum marianum L. Gaertn., Asteraceae (Milk thistle or Silymarin). These formulations, namely NSupple (without silymarin) and NSupple_Silybum (with silymarin) were tested over 180 days in overweight/obese volunteers from Brazil's southeastern region. We accessed fecal gut microbiota by partial 16S rRNA sequences; cytokines expression by CBA; anthropometrics, quality of life and sleep, as well as metabolic and hormonal parameters, at baseline (T0) and 180 days (T180) post-supplementation. Results demonstrated gut microbiota reshaping at phyla, genera, and species level post-supplementation. The Bacteroidetes phylum, Bacteroides, and Prevotella genera were positively modulated especially in the NSupple_Silybum group. Gut microbiota modulation was associated with improved sleep patterns, quality-of-life perception, cytokines expression, and anthropometric parameters post-supplementation. Our findings suggest that the nutraceutical blends positively enhance cardiometabolic and inflammatory markers. Particularly, NSupple_Silybum modulated microbiota composition, underscoring its potential significance in ameliorating metabolic dysregulation. Clinical trial registry number: NCT04810572. 23/03/2021.

Timing Matters: Time of Day Impacts the Ergogenic Effects of Caffeine-A Narrative Review

Caffeine has attracted significant attention from researchers in the sports field due to its well-documented ergogenic effects across various athletic disciplines. As research on caffeine continues to progress, there has been a growing emphasis on evaluating caffeine dosage and administration methods. However, investigations into the optimal timing of caffeine intake remain limited. Therefore, this narrative review aimed to assess the ergogenic effects of caffeine administration at different times during the morning (06:00 to 10:00) and evening (16:00 to 21:00). The review findings suggest that circadian rhythms play a substantial role in influencing sports performance, potentially contributing to a decline in morning performance. Caffeine administration has demonstrated effectiveness in mitigating this phenomenon, resulting in ergogenic effects and performance enhancement, even comparable to nighttime levels. While the specific mechanisms by which caffeine regulates circadian rhythms and influences sports performance remain unclear, this review also explores the mechanisms underlying caffeine's ergogenic effects, including the adenosine receptor blockade, increased muscle calcium release, and modulation of catecholamines. Additionally, the narrative review underscores caffeine's indirect impact on circadian rhythms by enhancing responsiveness to light-induced phase shifts. Although the precise mechanisms through which caffeine improves morning performance declines via circadian rhythm regulation necessitate further investigations, it is noteworthy that the timing of caffeine administration significantly affects its ergogenic effects during exercise. This emphasizes the importance of considering caffeine intake timing in future research endeavors to optimize its ergogenic potential and elucidate its mechanisms.

The Development and Validation of the Health Belief Model for Shift Workers (HBM-SW) Scale

OBJECTIVE

Shift work is associated with circadian misalignment, sleep loss, and suboptimal health behaviors, which may contribute to longer term negative health outcomes. To inform future interventions for shift workers, the present study aimed to develop and evaluate the Health Belief Model for Shift Workers (HBM-SW) scale.

METHODS

The HBM-SW development involved a seven-step process, including a literature review, expert panel analysis, cognitive interviews with shift workers, and a trial with a pilot sample of shift workers (n = 153). Utilizing exploratory factor analysis for factor identification and item reduction, the developed scale loaded on seven factors in line with the theoretical framework of the Health Belief Model: Perceived Threat, Perceived Severity, Perceived Benefits, Perceived Barriers, Cues to Action, Self-efficacy, and Health Motivation. Validation of the scale was conducted utilizing Pittsburgh Sleep Quality Index, International Physical Activity Questionnaire, and Food Frequency Questionnaire.

RESULTS

The pilot sample had an average age of 34.0 (18.0) years, was majority female (54.2%), with an average of 8.0 (11.0) years shift work experience. The HBM-SW showed good - excellent (α = 0.74-0.93) internal consistency and moderate - good (ICC = 0.64-0.89) test re-test reliability. Using health behavior outcome measures, the HBM-SW scale showed meaningful correlations with sleep quality, sleep duration, diet quality and leisure time physical activity, and acceptable validity and reliability. Further testing should be conducted in a larger sample to facilitate confirmatory factor analysis.

CONCLUSIONS

The developed Health Belief Model for Shift Workers scale is likely beneficial for use in future studies of interventions for shift workers.

Circadian rhythms tied to changes in brain morphology in a densely-sampled male

Circadian, infradian, and seasonal changes in steroid hormone secretion have been tied to changes in brain volume in several mammalian species. However, the relationship between circadian changes in steroid hormone production and rhythmic changes in brain morphology in humans is largely unknown. Here, we examined the relationship between diurnal fluctuations in steroid hormones and multiscale brain morphology in a precision imaging study of a male who completed forty MRI and serological assessments at 7 A.M. and 8 P.M. over the course of a month, targeting hormone concentrations at their peak and nadir. Diurnal fluctuations in steroid hormones were tied to pronounced changes in global and regional brain morphology. From morning to evening, total brain volume, gray matter volume, and cortical thickness decreased, coincident with decreases in steroid hormone concentrations (testosterone, estradiol, and cortisol). In parallel, cerebrospinal fluid and ventricle size increased from A.M. to P.M. Global changes were driven by decreases within the occipital and parietal cortices. These findings highlight natural rhythms in brain morphology that keep time with the diurnal ebb and flow of steroid hormones.

Sleep loss impairs blood-brain barrier function: Cellular and molecular mechanisms

Sleep is a physiological process that preserves the integrity of the neuro-immune-endocrine network to maintain homeostasis. Sleep regulates the production and secretion of hormones, neurotransmitters, cytokines and other inflammatory mediators, both at the central nervous system (CNS) and at the periphery. Sleep promotes the removal of potentially toxic metabolites out of the brain through specialized systems such as the glymphatic system, as well as the expression of specific transporters in the blood-brain barrier. The blood-brain barrier maintains CNS homeostasis by selectively transporting metabolic substrates and nutrients into the brain, by regulating the efflux of metabolic waste products, and maintaining bidirectional communication between the periphery and the CNS. All those processes are disrupted during sleep loss. Brain endothelial cells express the blood-brain barrier phenotype, which arises after cell-to-cell interactions with mural cells, like pericytes, and after the release of soluble factors by astroglial endfeet. Astroglia, pericytes and brain endothelial cells respond differently to sleep loss; evidence has shown that sleep loss induces a chronic low-grade inflammatory state at the CNS, which is associated with blood-brain barrier dysfunction. In animal models, blood-brain barrier dysfunction is characterized by increased blood-brain barrier permeability, decreased tight junction protein expression and pericyte detachment from the capillary wall. Blood-brain barrier dysfunction may promote defects in brain clearance of potentially neurotoxic metabolites and byproducts of neural physiology, which may eventually contribute to neurodegenerative diseases. This chapter aims to describe the cellular and molecular mechanisms by which sleep loss modifies the function of the blood-brain barrier.

Maternal dietary and environmental factors associated with infant circadian rhythm, growth, and temperament: Research protocol for a prospective cohort study

Introduction: Emerging evidence has been explored to determine the factors affecting the development of infant circadian rhythm. While fetal programming happens during the pregnancy period, external environmental cues and infant nutritional programming can have substantial effects on the infant circadian rhythm. Understanding prenatal and postnatal factors determining infant circadian rhythm can improve future interventions in optimizing maternal and infant health. Methods: This is a prospective observational cohort study, targeting 216 pregnant women from government maternity clinics in Kuala Lumpur, Malaysia. Pregnant women will be recruited at third trimester (baseline), and follow up at 3 months, and 6 months. A subsample will be collected for salivary cortisol analysis to determine circadian rhythm of the mother and infant at third trimester and 3 months. Data of eating misalignment, light exposure, chronotype, infant temperament, sleep quality, and mood will be collected via validated questionnaires. Anthropometric data and birth outcomes will be collected from antenatal and postnatal health records. Summary: Studies on infant circadian rhythm development have yet to be explored and established, hence this study presents a novel approach to identify the factors from prenatal to postnatal periods on infant circadian rhythm and its influence on growth and temperament. Findings from this study will provide insights in the critical timing which has larger effects on infant circadian rhythm development for future interventions to be conducted.

Link between circadian rhythm and benign prostatic hyperplasia (BPH)/lower urinary tract symptoms (LUTS)

BACKGROUND

Benign prostatic hyperplasia (BPH) is the most common urologic disease in aging males, affecting 50% of men over 50 and up to 80% of men over 80 years old. Its negative impact on health-related quality of life implores further investigation into its risk factors and strategies for effective management. Although the exact molecular mechanisms underlying pathophysiological onset of BPH are poorly defined, the current hypothesized contributors to BPH and lower urinary tract symptoms (LUTS) include aging, inflammation, metabolic syndrome, and hormonal changes. These processes are indirectly influenced by circadian rhythm disruption. In this article, we review the recent evidence on the potential association of light changes/circadian rhythm disruption and the onset of BPH and impact on treatment.

METHODS

A narrative literature review was conducted using PubMed and Google Scholar to identify supporting evidence. The articles referenced ranged from 1975 to 2023.

RESULTS

A clear relationship between BPH/LUTS and circadian rhythm disruption is yet to be established. However, common mediators influence both diseases, including proinflammatory states, metabolic syndrome, and hormonal regulation that can be asserted to circadian disruption. Some studies have identified a possible relationship between general LUTS and sleep disturbance, but little research has been done on the medical management of these diseases and how circadian rhythm disruption further affects treatment outcomes.

CONCLUSIONS

There is evidence to implicate a relationship between BPH/LUTS and circadian rhythm disruptions. However, there is scarce literature on potential specific link in medical management of the disease and treatment outcomes with circadian rhythm disruption. Further study is warranted to provide BPH patients with insights into circadian rhythm directed appropriate interventions.

Mind over Microbes: Investigating the Interplay between Lifestyle Factors, Gut Microbiota, and Brain Health

BACKGROUND

The gut microbiota (GM) of the human body comprises several species of microorganisms. This microorganism plays a significant role in the physiological and pathophysiological processes of various human diseases.

METHODS

The literature review includes studies that describe causative factors that influence GM. The GM is sensitive to various factors like circadian rhythms, environmental agents, physical activity, nutrition, and hygiene that together impact the functioning and composition of the gut microbiome. This affects the health of the host, including the psycho-neural aspects, due to the interconnectivity between the brain and the gut. Hence, this paper examines the relationship of GM with neurodegenerative disorders in the context of these aforesaid factors.

CONCLUSION

Future studies that identify the regulatory pathways associated with gut microbes can provide a causal link between brain degeneration and the gut at a molecular level. Together, this review could be helpful in designing preventive and treatment strategies aimed at GM, so that neurodegenerative diseases can be treated.

The relationship between autoimmune thyroid disease, thyroid nodules and sleep traits: a Mendelian randomization study

Background

Previous studies have suggested a potential association between Autoimmune thyroid disease Thyroid nodules and Sleep Traits, but the evidence is limited and controversial, and the exact causal relationship remains uncertain.

Objective

Therefore, we employed a MR analysis to investigate the causal relationship between Autoimmune thyroid disease, Thyroid nodules and Sleep Traits.

Methods

To explore the interplay between Autoimmune thyroid disease Thyroid nodules and Sleep Traits, we employed MR studies utilizing summary statistics derived from GWAS in individuals of European ancestry. To ensure robustness, multiple techniques were employed to assess the stability of the causal effect, including random-effect inverse variance weighted, weighted median, MR-Egger regression, and MR-PRESSO. Heterogeneity was evaluated using Cochran's Q value. Additionally, we investigated the presence of horizontal pleiotropy through MR-Egger regression and MR-PRESSO.

Results

The IVW method indicates a significant causal relationship between "Getting up" and autoimmune hypothyroidism, as revealed by the IVW method (OR: 0.59, 95% CI: 0.45 to 0.78, P-value = 1.99e-4). Additionally, there might be a potential correlation between sleep duration and autoimmune hypothyroidism (OR: 0.76, 95% CI: 0.60 to 0.79, P-value = 0.024). Moreover, the observed potential positive link between daytime nap and thyroid nodules (OR: 1.66, 95% CI: 1.07 to 2.58, P-value = 0.023) is subject to caution, as subsequent MR PRESSO testing reveals the presence of horizontal pleiotropy, raising concerns about the reliability of the findings. The findings suggested a potential inverse association between Autoimmune hypothyroidism and Getting up (OR: 0.99, 95% CI: 0.98 to 1.00, P-value = 6.66e-3).As the results of MR-Egger method(OR: 1.00, 95% CI: 0.98 to 1.02, P-value = 0.742) exhibited an opposing trend to that observed with the IVW method and the results did not reach significance after P-value correction.

Conclusion

The results of our study reveal a notable cause-and-effect relationship between Getting up and Autoimmune hypothyroidism, indicating its potential role as a protective factor against this condition. However, no causal connection was observed between sleep traits and Graves' disease or Thyroid nodules.

Associations of Circadian Rest-Activity Rhythms With Affect and Cognition in Community-Dwelling Stroke Survivors: An Ambulatory Assessment Study

BACKGROUND

Rest-activity rhythm (RAR) is a modifiable behavioral factor associated with affect and cognition. Identifying RAR characteristics associated with affect and cognition among stroke survivors provides insight into preventing poststroke affective and cognitive impairment.

OBJECTIVE

To examine the associations of RAR characteristics with affect and cognition among community-dwelling stroke survivors.

METHODS

Forty participants with mild stroke (mean age = 52.8; 42.5% female; 55% White) reported their affect and cognitive complaints using ecological momentary assessment and wore an accelerometer for 7 consecutive days and completed the National Institutes of Health Toolbox Cognition Battery. RAR characteristics were extracted using parametric and non-parametric approaches. Multivariable linear regressions were used to identify RAR characteristics associated with affect and cognition.

RESULTS

Later onset of rest (B = 0.45; P = .008) and activity (B = 0.36; P = .041) were positively associated with depressed affect. These associations were reversed for cheerful effect (rest onset: B = -0.42; P = .017; activity onset: B = -0.39; P = .033). Cheerful affect was also positively associated with relative amplitude (ie, distinctions in activity levels between rest and activity; B = .39; P = .030). Intra-daily variability (ie, RAR fragmentation; B = 0.35; P = .042) and later onset of activity (B = .36; P = .048) were positively associated with cognitive complaints. Less erratic RAR was positively associated with fluid cognition (B = 0.29; P = .036); RAR fragmentation was positively associated with crystallized cognition (B = 0.39; P = .015).

CONCLUSIONS

We identified RAR correlates of affect and cognition among stroke survivors, highlighting the value of managing RAR and sleep in stroke rehabilitation. Future studies should test whether advancing the onset of rest and activity, promoting a regular active lifestyle, and improving rest and sleep in the nighttime protect stroke survivors from affective and cognitive impairment.

Top-down and bottom-up alterations of connectivity patterns of the suprachiasmatic nucleus in chronic insomnia disorder

The importance of the suprachiasmatic nucleus (SCN, also called the master circadian clock) in regulating sleep and wakefulness has been confirmed by multiple animal research. However, human studies of SCN in vivo are still nascent. Recently, the development of resting-state functional magnetic resonance imaging (fMRI) has made it possible to study SCN-related connectivity changes in patients with chronic insomnia disorder (CID). Hence, this study aimed to explore whether sleep-wake circuitry (i.e., communication between the SCN and other brain regions) is disrupted in human insomnia. Forty-two patients with CID and 37 healthy controls (HCs) underwent fMRI scanning. Resting-state functional connectivity (rsFC) and Granger causality analysis (GCA) were performed to find abnormal functional and causal connectivity of the SCN in CID patients. In addition, correlation analyses were conducted to detect associations between features of disrupted connectivity and clinical symptoms. Compared to HCs, CID patients showed enhanced rsFC of the SCN-left dorsolateral prefrontal cortex (DLPFC), as well as reduced rsFC of the SCN-bilateral medial prefrontal cortex (MPFC); these altered cortical regions belong to the "top-down" circuit. Moreover, CID patients exhibited disrupted functional and causal connectivity between the SCN and the locus coeruleus (LC) and the raphe nucleus (RN); these altered subcortical regions constitute the "bottom-up" pathway. Importantly, the decreased causal connectivity from the LC-to-SCN was associated with the duration of disease in CID patients. These findings suggest that the disruption of the SCN-centered "top-down" cognitive process and "bottom-up" wake-promoting pathway may be intimately tied to the neuropathology of CID.

Chrononutrition in traditional European medicine-Ideal meal timing for cardiometabolic health promotion

Meal timing plays a crucial role for cardiometabolic health, given the circadian regulation of cardiometabolic function. However, to the best of our knowledge, no concept of meal timing exists in traditional European medicine (TEM). Therefore, in this narrative review, we aim to define the optimal time slot for energy intake and optimal energy distribution throughout the day in a context of TEM and explore further implications. By reviewing literature published between 2002 and 2022, we found that optimal timing for energy intake may be between 06:00 and 09:00, 12:00 and 14:00, and between 15:00 and 18:00, with high energy breakfast, medium energy lunch and low energy dinner and possibly further adjustments according to one's chronotype and genetics. Also, timing and distribution of energy intake may serve as a novel therapeutic strategy to optimize coction, a concept describing digestion and metabolism in TEM. Please cite this article as: Eberli NS, Colas L, Gimalac A. Chrononutrition in traditional European medicine-Ideal meal timing for cardiometabolic health promotion. J Integr Med. 2024; 22(2);115-125.

Circadian rhythm and sleep disruptions in relation to prenatal stress and depression symptoms

Circadian rhythm and sleep are related to health, but there is little data on the relationship between the sleep/wake rhythm and mood at different stages of pregnancy. The aim of this prospective, longitudinal study was to investigate the associations of circadian rhythm and sleep disruptions with stress and depression among women in early and late pregnancy. The participants were 26 pregnant women. Objective and subjective estimations of circadian rhythm and sleep were administered, namely actigraphy and the Biological Rhythms Interview of Assessment in Neuropsychiatry in the form of a questionnaire. The Perceived Stress Scale and the Edinburgh Postnatal Depression Scale were also used. Subjectively perceived circadian rhythm disruptions were positively related to stress. Tendency to maintain a regular rhythm of sleep and activity in early pregnancy and subjectively perceived disruptions of circadian rhythms in late pregnancy were positively associated with prenatal depression in late pregnancy. Sleep fragmentation and long time spent in bed at night in early pregnancy were positively associated with stress and depression in late pregnancy. The results suggest the importance of flexibility and the ability to adapt one's circadian activities to the demands of the situation of pregnancy-related changes in lifestyle. They also indicate the significance of good-quality uninterrupted night sleep in early pregnancy.

Sleep and allergic diseases among young Chinese adults from the Singapore/Malaysia Cross-Sectional Genetic Epidemiology Study (SMCGES) cohort

BACKGROUND AND OBJECTIVE

Sleep disruption has been shown to affect immune function and thus influence allergic disease manifestation. The specific effects of sleep on allergic diseases, however, are less well-established; hence, in a unique population of young Chinese adults, we investigated the association between sleep and allergic disease.

METHODS

Young Chinese adults recruited from Singapore in the Singapore/Malaysia Cross-Sectional Genetic Epidemiology Study (SMCGES) were analyzed. We used the International Study of Asthma and Allergies in Childhood (ISAAC) protocol and a skin prick test to determine atopic dermatitis (AD), allergic rhinitis (AR), and asthma status. Information regarding total sleep time (TST) and sleep quality (SQ) was also obtained.

RESULTS

Of 1558 participants with a mean age of 25.0 years (SD = 7.6), 61.4% were female, and the mean total sleep time (TST) was 6.8 h (SD = 1.1). The proportions of AD, AR, and asthma were 24.5% (393/1542), 36.4% (987/1551), and 14.7% (227/1547), respectively. 59.8% (235/393) of AD cases suffered from AD-related sleep disturbances, 37.1% (209/564) of AR cases suffered from AR-related sleep disturbances, and 25.1% (57/227) of asthma cases suffered from asthma-related sleep disturbances. Only asthma cases showed a significantly lower mean TST than those without asthma (p = 0.015). Longer TST was significantly associated with lower odds of AR (OR = 0.905, 95% CI = 0.820-0.999) and asthma (OR = 0.852, 95% CI = 0.746-0.972). Linear regression analyses showed that lower TST was significantly associated with asthma (β =  - 0.18, SE = 0.076, p-value = 0.017), and AR when adjusted for AR-related sleep disturbances (β =  - 0.157, SE = 0.065, p-value = 0.016). Only sleep disturbances due to AR were significantly associated with a poorer SQ (OR = 1.962, 95% CI = 1.245-3.089).

CONCLUSIONS

We found that sleep quality, but not sleep duration was significantly poorer among AD cases, although the exact direction of influence could not be determined. In consideration of the literature coupled with our findings, we posit that TST influences allergic rhinitis rather than vice versa. Finally, the association between TST and asthma is likely mediated by asthma-related sleep disturbances, since mean TST was significantly lower among those with nighttime asthma symptoms. Future studies could consider using objective sleep measurements coupled with differential expression analysis to investigate the pathophysiology of sleep and allergic diseases.

Effects of BXSMD on ESR1 and ESR2 expression in CSD female mice

ETHNIC PHARMACOLOGICAL RELEVANCE

Due to the rapid pace of modern society, chronic insomnia has become universal phenomenon. In China, Banxia Shumi Decoction (BXSMD) has been used in treating chronic insomnia for thousands of years, but its chemical composition and action mechanism are still unknown.

AIM OF THE STUDY

This study aims to explore the chemical composition of BXSMD and its effects on Estrogen receptor 1 (ESR1) and Estrogen receptor 2 (ESR2) in mice with chronic sleep deprivation (CSD).

MATERIALS AND METHODS

UHPLC-Q-Orbitrap-MS/MS was applied in determining the chemical composition of BXSMD. After 21-day sleep deprivation (SD) in platform water environment, CSD mice model was prepared. By conducting open field test, 24-h autonomic diurnal and nocturnal activity of mice in each group was detected. ELISA was employed to measure the contents of 5-HT, DA, NE, GABA, Glu, and MT. With RT-PCR, Western blot (WB), and immunohistochemistry (IHC), mRNA and protein expressions of ESR1 and ESR2 in the hypothalamus and hippocampus were tested.

RESULTS

BXSMD included ferulic acid, kaverol, daidzein, apigenin, berberine, adenosine, aesculin, vanillin, naringin, and glycine, which might constitute the material basis forthe improvement of chronic insomnia. With BXSMD, the total moving distance and the rest time in dark period of CSD mice were shortened, while its rest time in light period was increased. Besides, BXSMD enhanced the contents of 5-HT, GABA, and MT in CSD mice, and decreased the contents of Glu, NE, and DA. BXSMD elevated the mRNA of Esr1 and Esr2, and elevated the protein expressions of ESR1 and ESR2 in the hypothalamus and hippocampus of CSD mice.

CONCLUSIONS

BXSMD contains various chemical components for sleep-wake regulation, with the mechanism of stimulating estrogen signaling pathway by regulating the expressions of ESR1 and ESR2, ultimately realizing the regulation to sleep-wake disorder caused by CSD.

Fasting diets: what are the impacts on eating behaviors, sleep, mood, and well-being?

Fasting diets (FDs) have drawn great attention concerning their contribution to health and disease over the last decade. Despite considerable interest in FDs, the effect of fasting diets on eating behaviors, sleep, and mood-essential components of diet satisfaction and mental health- has not been addressed comprehensively. Understanding the critical role that fasting plays in these elements will open up potential treatment avenues that have not yet been explored. The aim of the present paper was to conduct a comprehensive critical review exploring the effects of fasting on eating behaviors, sleep, and mood. There is currently a lack of clarity regarding which fasting option yields the most advantageous effects, and there is also a scarcity of consistent trials that assess the effects of FDs in a comparable manner. Similarly, the effects and/or treatment options for utilizing FDs to modify eating and sleep behaviors and enhance mood are still poorly understood. Further researches aiming at understanding the impacts of various fasting regimes, providing new insights into the gut-brain axis and offering new treatment avenues for those with resistant anxiety and depression, are warranted. Alteration of eating behaviors can have lasting effects on various physiological parameters. The use of fasting cures can underpin ancient knowledge with scientific evidence to form a new approach to the prevention and treatment of problems associated with co-morbidities or challenges pertaining to eating behaviors. Therefore, a thorough examination of the various fasting regimens and how they impact disease patterns is also warranted.

Integrative Lighting Aimed at Patients with Psychiatric and Neurological Disorders

The purpose of this paper is to investigate the impact of circadian lighting-induced melatonin suppression on patients with psychiatric and neurological disorders in hospital wards by using an ad-hoc metrology framework and the subsequent metrics formalized by the CIE in 2018. A measurement scheme was conducted in hospital ward rooms in the Department of Neurology, Zealand University Hospital, at Roskilde in Denmark, to evaluate the photometric and colorimetric characteristics of the lighting system, as well as its influence on the circadian rhythm of the occupants. The measurement scheme included point measurements and data logging, using a spectrophotometer mounted on a tripod with adjustable height to assess the newly installed circadian lighting system. The measured spectra were uploaded to the Luox platform to calculate illuminance, CCT, MEDI, etc., in accordance with the CIE S026 standard. Furthermore, the MLIT based on MEDI data logging results was calculated. In addition to CIE S026, we have investigated the usefulness of melatonin suppression models for the assessment of circadian performance regarding measured light. From the results, the lighting conditions in the patient room for both minimal and abundant daylight access were evaluated and compared; we found that access to daylight is essential for both illumination and circadian entrainment. It can be concluded that the measurement scheme, together with the use of the Luox platform and Canva template, is suitable for the accurate and satisfactory measurement of integrative lighting that aligns with CIE requirements and recommendations.

Children's Sleep and Mental Health During the COVID-19 Pandemic

PURPOSE OF REVIEW

The COVID-19 pandemic and protracted home confinement required adjustments to schedules and routines generating concern about children's sleep. This review describes general considerations regarding children's sleep, changes and disturbances in their sleep during the pandemic, and the association of sleep measures with health and psychological outcomes in general and in the context of the pandemic.

RECENT FINDINGS

A number of studies found an increase in the duration of children's sleep with later bedtimes and waketimes for some children. The research also documented sleep disturbances and associations between children's sleep and psychological outcomes. The extent to which increased sleep duration and changed sleep behaviors translated into improved sleep quality and/or a change in sleep disturbances remains unclear. This review suggests the importance of considering children's sleep in other mass trauma situations including, for example, natural and man-made disasters, as well as pandemics.

Circadian Rhythms in Cardiovascular Function: Implications for Cardiac Diseases and Therapeutic Opportunities

Circadian rhythms are internal 24-h intrinsic oscillations that are present in essentially all mammalian cells and can influence numerous biological processes. Cardiac function is known to exhibit a circadian rhythm and is strongly affected by the day/night cycle. Many cardiovascular variables, including heart rate, heart rate variability (HRV), electrocardiogram (ECG) waveforms, endothelial cell function, and blood pressure, demonstrate robust circadian rhythms. Many experiential and clinical studies have highlighted that disruptions in circadian rhythms can ultimately lead to maladaptive cardiac function. Factors that disrupt the circadian rhythm, including shift work, global travel, and sleep disorders, may consequently enhance the risk of cardiovascular diseases. Some cardiac diseases appear to occur at particular times of the day or night; therefore, targeting the disease at particular times of day may improve the clinical outcome. The objective of this review is to unravel the relationship between circadian rhythms and cardiovascular health. By understanding this intricate interplay, we aim to reveal the potential risks of circadian disruption and discuss the emerging therapeutic strategies, specifically those targeting circadian rhythms. In this review, we explore the important role of circadian rhythms in cardiovascular physiology and highlight the role they play in cardiac dysfunction such as ventricular hypertrophy, arrhythmia, diabetes, and myocardial infarction. Finally, we review potential translational treatments aimed at circadian rhythms. These treatments offer an innovative approach to enhancing the existing approaches for managing and treating heart-related conditions, while also opening new avenues for therapeutic development.

Glucose Challenge Uncovers Temporal Fungibility of Metabolic Homeostasis Throughout the Day

Rhythmicity is a central feature of behavioral and biological processes including metabolism, however, the mechanisms of metabolite cycling are poorly understood. A robust oscillation in a network of key metabolite pathways downstream of glucose is described in humans, then these pathways mechanistically probed through purpose-built 13C6-glucose isotope tracing in Drosophila every 4h. A temporal peak in biosynthesis was noted by broad labelling of pathways downstream of glucose in wild-type flies shortly following lights on. Krebs cycle labelling was generally increased in a hyperactive mutant (fumin) along with glycolysis labelling primarily observed at dawn. Surprisingly, neither underlying feeding rhythms nor the presence of food explains the rhythmicity of glucose processing across genotypes. These results are consistent with clinical data demonstrating detrimental effects of mis-timed energy intake. This approach provides a window into the dynamic range of metabolic processing ability through the day and mechanistic basis for exploring circadian metabolic homeostasis in disease states.

Daily rhythms of diabetogenic factors in men: role of type 2 diabetes and body weight

Obesity is a major cause of type 2 diabetes. Transition from obesity to type 2 diabetes manifests in the dysregulation of hormones controlling glucose homeostasis and inflammation. As metabolism is a dynamic process that changes across 24 h, we assessed diurnal rhythmicity in a panel of 10 diabetes-related hormones. Plasma hormones were analysed every 2 h over 24 h in a controlled laboratory study with hourly isocaloric drinks during wake. To separate effects of body mass from type 2 diabetes, we recruited three groups of middle-aged men: an overweight (OW) group with type 2 diabetes and two control groups (lean and OW). Average daily concentrations of glucose, triacylglycerol and all the hormones except visfatin were significantly higher in the OW group compared to the lean group (P < 0.001). In type 2 diabetes, glucose, insulin, C-peptide, glucose-dependent insulinotropic peptide and glucagon-like peptide-1 increased further (P < 0.05), whereas triacylglycerol, ghrelin and plasminogen activator inhibitor-1 concentrations were significantly lower compared to the OW group (P < 0.001). Insulin, C-peptide, glucose-dependent insulinotropic peptide and leptin exhibited significant diurnal rhythms in all study groups (P < 0.05). Other hormones were only rhythmic in 1 or 2 groups. In every group, hormones associated with glucose regulation (insulin, C-peptide, glucose-dependent insulinotropic peptide, ghrelin and plasminogen activator inhibitor-1), triacylglycerol and glucose peaked in the afternoon, whereas glucagon and hormones associated with appetite and inflammation peaked at night. Thus being OW with or without type 2 diabetes significantly affected hormone concentrations but did not affect the timing of the hormonal rhythms.

Assessing the Association of Self-Reported Sleep Duration and Metabolic Syndrome Among Middle-Aged and Older Adults in China from the China Health and Retirement Longitudinal Survey

Objectives: We aim to investigate the correlation between sleep and metabolic syndrome (MS) among a community population 45 years of age and older in China. Methods: A cross-sectional analysis of 9096 participants from China health and longitudinal study was carried out. MS was defined by consensus criteria. Sleep durations were assessed by self-reported questionnaire. Odds ratio (OR) and 95% confidence intervals (CIs) for MS were obtained using multivariable-adjusted regression analysis. Results: Long habitual daytime sleep had a positive influence on MS (OR = 1.50, 95% CI = 1.10-2.06). For elderly, short daytime sleep significantly increased risk of MS (OR = 2.14, 95% CI = 1.25-3.67). Females with long daytime sleep was associated with increased risk of MS (OR = 1.54, 95% CI = 1.04-2.29). Conclusions: Daytime sleep significantly increased risk of MS for middle-aged and elderly Chinese. The hazard role of daytime sleep on MS was various between age and sex groups. Results of this study needed to be verified by future longitudinal studies.

Circadian Disruption in Night Shift Work and Its Association with Chronic Pulmonary Diseases

Globalization and the expansion of essential services over continuous 24 h cycles have necessitated the adaptation of the human workforce to shift-based schedules. Night shift work (NSW) causes a state of desynchrony between the internal circadian machinery and external environmental cues, which can impact inflammatory and metabolic pathways. The discovery of clock genes in the lung has shed light on potential mechanisms of circadian misalignment in chronic pulmonary disease. Here, the current knowledge of circadian clock disruption caused by NSW and its impact on lung inflammation and associated pathophysiology in chronic lung diseases, such as asthma, chronic obstructive pulmonary disease, pulmonary fibrosis, and COVID-19, is reviewed. Furthermore, the limitations of the current understanding of circadian disruption and potential future chronotherapeutic advances are discussed.

Colorimetric sensing assay based on aptamer-gold nanoparticles for rapid detection of salivary melatonin to monitor circadian rhythm sleep disorders

Salivary melatonin is a clinically used biomarker for diagnosing circadian rhythm sleep disorders. Current melatonin detection assays are complex, expensive, and in many cases do not adequately measure low levels of salivary melatonin. Precisely measuring melatonin levels at multiple time points is crucial for determining dim light melatonin onset to evaluate its circadian fluctuation as well as the extent of circadian disruption and consequently adapt treatment regimens. Moreover, melatonin low levels in saliva challenges the reliability of routine clinical testing. This paper presents the development of a novel, highly sensitive, yet cost-effective, colorimetric assay for the rapid detection of salivary melatonin utilizing aptamer-AuNPs. Among several types of the aptamer tested, the 36-mer MLT-A-2 aptamer-AuNP probe showed the highest sensitivity with a melatonin limit of detection of 0.0011 nM along with a limit of quantification of 0.0021 nM in saliva. Moreover, our assay showed preferential interaction with melatonin when tested in presence of other structurally similar counter-targets. Taken together, this study provides new parameters for a melatonin assay that meets adequate levels of sensitivity and selectivity. The developed colorimetric assay could be adapted in a point-of-care system for profiling salivary melatonin levels at multiple time points during 24 h, crucial for accurately diagnosing and monitoring circadian rhythm sleep disorders and beyond.

Impact of high-fat diet and exposure to constant light on reproductive competence of female ICR mice

Obesity and exposure to light at night are prevalent in modern society and associated with changes in physiology and behavior that can affect a female's ability to support offspring growth during pregnancy and lactation. A 2X3 factor study of ICR mice was conducted to determine the effect of diet [control (CON; 10% fat) or high fat (HF; 60% fat)] and exposure to regular 12 h light:dark cycles (LD) or continuous low (L5) or high (L100) lux of light on gestation length, birth litter size, milk composition and litter growth to lactation day 12. HF diet reduced birth litter size, but increased postnatal d 12 litter weight (P<0.05), whereas constant light tended to increase litter weight (P=0.07). Continuous light increased gestation length, altered dam feed intake, increased serum prolactin and increased final dam and mammary gland weight (P<0.05), while decreasing mammary ATP content and milk lactose (P<0.05). Correlation analysis indicated a positive relationship between final litter weight and mammary size, metabolic stores (e.g. maternal fat pad weight), kcal of feed intake, and gestation length (P<0.05). Although CON mice spent more time eating than HF dams, the calorically dense HF diet was related to greater rates of litter growth to peak lactation. Constant light circadian disrupting effects appear to be confounded by a potential long day photoperiod response exemplified by higher circulating levels of prolactin and increased body and mammary weight of females exposed to these conditions. Other model systems may be better to study the interacting effects of obesity and circadian disruption on reproductive competence.

Sleep Variability, Eating Timing Variability, and Carotid Intima-Media Thickness in Early Adulthood

Background Day-to-day variability in sleep patterns and eating timing may disrupt circadian rhythms and has been linked with various adverse cardiometabolic outcomes. However, the extent to which variability in sleep patterns and eating timing relate to atherosclerotic development in subclinical stages remains unclear. Methods and Results Generally healthy adults (N=62, 29.3±7.3 years, 66% female) completed 14 days of sleep and dietary assessments via wrist accelerometry and photo-assisted diet records, respectively. Variability in sleep duration, sleep onset, eating onset (time of first caloric consumption), eating offset (time of last caloric consumption), and caloric midpoint (time at which 50% of total daily calories are consumed) were operationalized as the SD across 14 days for each variable. Separate regression models evaluated the cross-sectional associations between sleep and eating variability metrics with end-diastolic carotid intima-media thickness (CIMT) measured via ultrasonography. Models adjusted for age, sex, systolic blood pressure, sleep duration, and total energy intake. Each 60-minute increase in sleep duration SD and sleep onset SD were associated with a 0.049±0.016 mm (P=0.003) and 0.048±0.017 mm (P=0.007) greater CIMT, respectively. Variability in eating onset and offset were not associated with CIMT; however, each 60-minute increase in caloric midpoint SD was associated with a 0.033±0.015 mm greater CIMT (P=0.029). Exploratory post hoc analyses suggested that sleep duration SD and sleep onset SD were stronger correlates of CIMT than caloric midpoint SD. Conclusions Variability in sleep patterns and eating timing are positively associated with clinically relevant increases in CIMT, a biomarker of subclinical atherosclerosis, in early adulthood.

Time of Day Effects on Anaerobic Performance Using a Nonmotorized Treadmill

ABSTRACT

Renziehausen, JM, Bergquist, AM, Park, J-H, Hill, EC, Wells, AJ, Stout, JR, and Fukuda, DH. Time of day effects on anaerobic performance using a nonmotorized treadmill. J Strength Cond Res 37(10): 2002-2007, 2023-The purpose of this study was to determine the effects of time of day on performance during a maximal effort sprinting assessment (30nmt) and determine potential differences based on chronotype and sex. Twenty-six recreationally active men (n = 12) and women (n = 14) between the ages of 18 and 35 years old (21.5 ± 2.4 years) completed the 30nmt at 9:00 am, 2:00 pm, and 7:00 pm in a randomized order over a 24-hour period. Resting heart rate and temperature assessments were taken at each visit. A dietary recall and the Morningness-Eveningness Questionnaire were used to assess kilocalories (kcals) and chronotype, respectively. Two-way (time x sex) repeated measures analyses of variance were conducted to determine differences in peak/mean power, peak/mean velocity, distance, resting heart rate, temperature, and kcals at each time point. Paired sample t tests were used to assess peak and nadir of each performance variable. A significance level was set at p < 0.05. There was a significant main effect for temperature (p < 0.001), resting heart rate (p = 0.007), and pre-exercise caloric intake (p = 0.021) throughout the day. No significant main effects for time were found for peak power (p = 0.766), mean power (p = 0.094), peak velocity (p = 0.497), mean velocity (p = 0.193), or distance (p = 0.262). There were no significant time × sex interactions for any dependent performance variables (p > 0.05). Significant differences were shown between the peak and nadir of each performance variable (p < 0.001). There were no significant differences in performance during maximal effort anaerobic assessments shown throughout the day; however, peak/nadir of performance times may be individualized and differ between morning types and intermediate types.

Green sleep: Immediate residential greenspace and access to larger green areas are associated with better sleep quality, in a longitudinal population-based cohort

OBJECTIVE

Sleep is pivotal to health, wellbeing and functioning in daily life, but sleep difficulties are common and may be affected by modifiable qualities in the residential surrounding environment, in terms of greenspace. However, population-based studies on individual-level greenspace and sleep are limited. The objective of the current study was thus to investigate prospective associations between fine-grained individual-level residential greenspace and sleep, and moderating effects of life style (physical activity, work status) and sex, in a nationwide population-based Swedish cohort.

METHODS

Participants of the Swedish Longitudinal Occupational Survey of Health (SLOSH)-a population-based sample of adults in Sweden-were studied during 2014-2018 (19,375 individuals; 43,062 observations). Residential greenspace land cover, and coherent green area size, were assessed via high resolution geographic information systems, at 50, 100, 300, 500 and 1000 m buffers around residences. Prospective greenspace and sleep associations were assessed via multilevel general linear models, adjusting for demographic, socioeconomic (individual and neighborhood), life style and urban factors.

RESULTS

Higher greenspace availability in the immediate residential surroundings (50 m and 100 m buffer zones) was associated with less sleep difficulties, even after adjustment for confounders. Greenspace effects were generally greater among non-working individuals. Among the physically active, and among non-working, greenspace and green area size further away from home (300, 500 and 1000 m, i.e. dependent on mobility) were also associated with less sleep difficulties.

CONCLUSIONS

Residential greenspace in the immediate residential surroundings is associated with significantly less sleep difficulties. Greenspace further away from home was associated with better sleep especially among the physically active, and non-working individuals. The results highlight the importance of greenspace in the immediate residential-surrounding environment for sleep, and the need to integrate health and environmental policies, urban planning and greening.

Normalization of the ATP1A1 Signalosome Rescinds Epigenetic Modifications and Induces Cell Autophagy in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death worldwide. In metabolic dysfunction-associated steatohepatitis (MASH)-related HCC, cellular redox imbalance from metabolic disturbances leads to dysregulation of the α1-subunit of the Na/K-ATPase (ATP1A1) signalosome. We have recently reported that the normalization of this pathway exhibited tumor suppressor activity in MASH-HCC. We hypothesized that dysregulated signaling from the ATP1A1, mediated by cellular metabolic stress, promotes aberrant epigenetic modifications including abnormal post-translational histone modifications and dysfunctional autophagic activity, leading to HCC development and progression. Increased H3K9 acetylation (H3K9ac) and H3K9 tri-methylation (H3K9me3) were observed in human HCC cell lines, HCC-xenograft and MASH-HCC mouse models, and epigenetic changes were associated with decreased cell autophagy in HCC cell lines. Inhibition of the pro-autophagic transcription factor FoxO1 was associated with elevated protein carbonylation and decreased levels of reduced glutathione (GSH). In contrast, normalization of the ATP1A1 signaling significantly decreased H3K9ac and H3K9me3, in vitro and in vivo, with concomitant nuclear localization of FoxO1, heightening cell autophagy and cancer-cell apoptotic activities in treated HCC cell lines. Our results showed the critical role of the ATP1A1 signalosome in HCC development and progression through epigenetic modifications and impaired cell autophagy activity, highlighting the importance of the ATP1A1 pathway as a potential therapeutic target for HCC.

Sleep Patterns, Plasma Metabolome, and Risk of Incident Type 2 Diabetes Mellitus

CONTEXT

A healthy sleep pattern has been related to a lower risk of type 2 diabetes mellitus (T2DM).

OBJECTIVE

We aimed to identify the metabolomic signature for the healthy sleep pattern and assess its potential causality with T2DM.

METHODS

This study included 78 659 participants with complete phenotypic data (sleep information and metabolomic measurements) from the UK Biobank study. Elastic net regularized regression was applied to calculate a metabolomic signature reflecting overall sleep patterns. We also performed genome-wide association analysis of the metabolomic signature and one-sample mendelian randomization (MR) with T2DM risk.

RESULTS

During a median of 8.8 years of follow-up, we documented 1489 incident T2DM cases. Compared with individuals who had an unhealthy sleep pattern, those with a healthy sleep pattern had a 49% lower risk of T2DM (multivariable-adjusted hazard ratio [HR], 0.51; 95% CI, 0.40-0.63). We further constructed a metabolomic signature using elastic net regularized regressions that comprised 153 metabolites, and robustly correlated with sleep pattern (r = 0.19; P = 3×10-325). In multivariable Cox regressions, the metabolomic signature showed a statistically significant inverse association with T2DM risk (HR per SD increment in the signature, 0.56; 95% CI, 0.52-0.60). Additionally, MR analyses indicated a significant causal relation between the genetically predicted metabolomic signature and incident T2DM (P for trend < .001).

CONCLUSION

In this large prospective study, we identified a metabolomic signature for the healthy sleep pattern, and such a signature showed a potential causality with T2DM risk independent of traditional risk factors.