The metabolic burden of sleep loss

Associations of exposure to transportation noise with sleep and cardiometabolic health: exploration of pathways

Transportation noise is known to increase the risk for multiple cardiometabolic diseases. However, the complex relationship between different noise sources, sleep, metabolic and cardiovascular risk factors is still not well understood. To study how chronic noise exposure contributes to the development of cardiometabolic disease, data from the cross-sectional COmPLETE-Health Study were used, which includes a comprehensive cardiometabolic assessment and accelerometer-based behavioral monitoring from 527 healthy Swiss adults aged 20-89 years. Road traffic, aircraft and railway noise were modelled at the participants' home addresses, followed by a measurement based model validation. For each noise source, the following conceptual model was tested using Structural Equation Modelling (SEM): Noise was assumed to affect the two latent constructs metabolic risk (defined by waist-to-hip ratio and HDL-cholesterol) and cardiovascular risk (defined by systolic blood pressure and pulse wave velocity) directly, as well as indirectly via sleep efficiency. The SEM showed very good fit of the conceptual models. Road traffic noise had a significant, small-medium sized direct link with cardiovascular risk (β = 0.16, 95 %CI: 0.01, 0.31), while negligible associations with sleep efficiency or metabolic risk were observed. Conversely, railway noise was mainly associated with lower sleep efficiency (β = -0.15, 95 %CI: -0.23, -0.06) and increased metabolic risk (β = 0.14, 95 %CI: -0.05, 0.32), with only a negligible association with cardiovascular risk. The inclusion of physical activity did not change results, suggesting that associations of noise with cardiometabolic health are robust to the additional consideration of physical activity. These insights are important to inform effective measures to protect populations from harmful transportation noise exposure.

Impact of night sentry duties on cardiometabolic health in military personnel

This article examines the study by Lin et al, which explores the effects of night sentry duties on cardiometabolic health in military personnel. The research identifies significant correlations between the frequency of night shifts and negative cardiometabolic outcomes, such as elevated resting pulse rates and lowered levels of high-density lipoprotein cholesterol. These outcomes underscore the health risks linked to partial sleep deprivation, a common challenge in military environments. The editorial highlights the clinical significance of these findings, advocating for the implementation of targeted health interventions to mitigate these risks. Strategies such as structured sleep recovery programs and lifestyle modifications are recommended to improve the health management of military personnel engaged in nocturnal duties. By addressing these issues, military health management can better safeguard the well-being and operational readiness of its personnel.

Food intake enhances hippocampal sharp wave-ripples

Effective regulation of energy metabolism is critical for survival. Metabolic control involves various nuclei within the hypothalamus, which receive information about the body's energy state and coordinate appropriate responses to maintain homeostasis, such as thermogenesis, pancreatic insulin secretion, and food-seeking behaviors. It has recently been found that the hippocampus, a brain region traditionally associated with memory and spatial navigation, is also involved in metabolic regulation. Specifically, hippocampal sharp wave-ripples (SWRs), which are high-frequency neural oscillations supporting memory consolidation and foraging decisions, have been shown to reduce peripheral glucose levels. However, whether SWRs are enhanced by recent feeding-when the need for glucose metabolism increases, and if so, whether feeding-dependent modulation of SWRs is communicated to other brain regions involved in metabolic regulation-remains unknown. To address these gaps, we recorded SWRs from the dorsal CA1 region of the hippocampus of mice during sleep sessions before and after consumption of meals of varying caloric values. We found that SWRs occurring during sleep are significantly enhanced following food intake, with the magnitude of enhancement being dependent on the caloric content of the meal. This pattern occurred under both food-deprived and ad libitum feeding conditions. Moreover, we demonstrate that GABAergic neurons in the lateral hypothalamus, which are known to regulate food intake, exhibit a robust SWR-triggered increase in activity. These findings identify the satiety state as a factor modulating SWRs and suggest that hippocampal-lateral hypothalamic communication is a potential mechanism by which SWRs could modulate peripheral metabolism and food intake.

Foods for Sleep Improvement: A Review of the Potential and Mechanisms Involved

Insomnia affects one-third of the world's population; the negative effects of insomnia are significant, and traditional insomnia medications have numerous side effects and cause considerable suffering. This has aroused interest in obtaining sleep-improving substances from foods. This study conducted a comprehensive literature review using Web of Science and PubMed with keywords like "sleep", "insomnia", and "food". A subsequent summary of the literature revealed that certain foods, including milk, Ziziphus jujuba, Lactuca sativa, ginseng, Schisandra chinensis, and Juglans regia, etc., are purported to enhance sleep quality by prolonging sleep duration, reducing sleep latency, and alleviating anxiety. The mechanisms of these foods' effects mainly occur via the central nervous system, particularly the gamma-aminobutyric acid (GABA)ergic and 5-hydroxytryptamine (5-HT)ergic systems. Although this review supports the fact that they have potential, further research is needed. There are also issues such as more limited foods, fewer mechanisms, fewer pharmacokinetic studies, and more traditional research models being involved. These need to be addressed in the future to adequately address the problem of insomnia. It is hoped that this study will contribute to research into foods with sleep-improving properties and, in the future, provide an effective natural alternative for those seeking medication.

Food intake enhances hippocampal sharp wave-ripples

Effective regulation of energy metabolism is critical for survival. Metabolic control involves various nuclei within the hypothalamus, which receive information about the body's energy state and coordinate appropriate responses to maintain homeostasis, such as thermogenesis, pancreatic insulin secretion, and food-seeking behaviors. It has recently been found that the hippocampus, a brain region traditionally associated with memory and spatial navigation, is also involved in metabolic regulation. Specifically, hippocampal sharp wave ripples (SWRs), which are high-frequency neural oscillations supporting memory consolidation and foraging decisions, have been shown to reduce peripheral glucose levels. However, whether SWRs are enhanced by recent feeding-when the need for glucose metabolism increases, and if so, whether feeding-dependent modulation of SWRs is communicated to other brain regions involved in metabolic regulation, remains unknown. To address these gaps, we recorded SWRs from the dorsal CA1 region of the hippocampus of mice during sleep sessions before and after consumption of meals of varying caloric values. We found that SWRs occurring during sleep are significantly enhanced following food intake, with the magnitude of enhancement being dependent on the caloric content of the meal. This pattern occurred under both food-deprived and ad libitum feeding conditions. Moreover, we demonstrate that GABAergic neurons in the lateral hypothalamus, which are known to regulate food intake, exhibit a robust SWR-triggered increase in activity. These findings identify the satiety state as a factor modulating SWRs and suggest that hippocampal-lateral hypothalamic communication is a potential mechanism by which SWRs could modulate peripheral metabolism and food intake.

Sex differences in the relationship between short sleep duration and obesity among koreans

This cross-sectional study examined the relationship between short sleep duration and obesity by analysing data from 3,950 participants aged 40-69 years who took part in the 2003-2004 follow-up survey of the Korean Genome and Epidemiologic Study. Based on the subjective experience of morning fatigue, short sleep duration was defined as < 5 h of sleep. Short sleep duration was significantly associated with general obesity, as measured by body mass index (adjusted odds ratios [confidence intervals], 1.246 [1.016-1.529]); these associations became stronger as the severity of general obesity worsened. Analysing data separately by sex, we detected a relationship between short sleep duration and general obesity in females only. Considering the impact of age, the relationship was detected only in females aged 40-59 years old. In females aged 40-59 years, both general obesity (1.518 [1.110-2.075]) and neck obesity (1.425 [1.045-1.945]) were associated with short sleep duration. Our study established a correlation between short sleep duration and general obesity, specifically in females and those aged 40-59 years. This finding highlights the importance of adequate sleep to treat and prevent obesity in this demographic group.

The Role of the Chronotype in Developing an Excessive Body Weight and Its Complications-A Narrative Review

The chronotype, the personal predisposition towards morning or evening activities, significantly influences health conditions, sleep, and eating regulations. Individuals with evening chronotypes are often at a higher risk for weight gain due to misalignment between their natural tendencies of functioning and social schedules, resulting in insufficient sleep, disruptions in eating habits, and decreased physical activity levels. Often, impaired glucose tolerance and changes in melatonin, adiponectin, and leptin secretion, along with alterations in the clock gene functions in subjects with evening preferences, may be predisposed to obesity. These disturbances contribute to metabolic dysregulation, which may lead to the subsequent onset of obesity complications, such as hypertension, type 2 diabetes, sleep apnea, and liver diseases. Targeting critical components of the circadian system and synchronizing people's chronotypes with lifestyle conditions could deliver potential strategies for preventing and treating metabolic disorders. Thus, it is recommended to take a personalized chronobiological approach to maintain a normal body weight and metabolic health. Nevertheless, future studies are needed to identify the clear mechanisms between the chronotype and human health. This article provides a narrative review and discussion of recent data to summarize studies on the circadian rhythm in the context of obesity. The manuscript represents a comprehensive overview conducted between August and November 2024 using the National Library of Medicine browser (Medline, Pub-Med, Web of Science).

An integrative approach prioritizes the orphan GPR61 genomic region in tissue-specific regulation of chronotype

Objectives

Chronotype, a manifestation of circadian rhythms, affects morning or evening preferences and ease of getting-up. This study explores the genetic basis of morning chronotype and ease of getting-up, focusing on the G protein-coupled receptor locus, GPR61.

Methods

We analyzed the genetic correlation between chronotype and ease of getting-up using linkage disequilibrium score regression with summary statistics from the UK Biobank (n=453,379). We prioritized shared signals between chronotype and ease of getting-up using the Human Genetic Evidence (HuGE) score. We assessed the significance of GPR61 and the lead variant rs12044778 through colocalization and in-silico analyses from ENCODE, Genotype-Tissue Expression, Hi-C, and Knockout Mouse Project databases to explore potential regulatory roles of causal genes.

Results

We identified a strong genetic correlation (Rg=0.80, P=4.9 x10 324 ) between chronotype and ease of getting-up. Twenty-three genes, including three circadian core clock components, had high HuGE scores for both traits. Lead variant rs12044778 in GPR61 was prioritized for its high HuGE score (45) and causal pleiotropy (posterior probability=0.98). This morningness variant influenced gene expression in key tissues: decreasing GPR61 in tibial nerve, increasing AMIGO1 in subcutaneous adipose, and increasing ATXN7L2 in the cerebellum. Functional knockout models showed GPR61 knockout increased fat mass and activity, AMIGO1 knockout increased activity, and ATXN7L2 knockout reduced body weight without affecting activity.

Conclusions

Our findings reveal pleiotropic genetic factors influencing chronotype and ease of getting-up, emphasizing GPR61 's rs12044778 and nearby genes like AMIGO1 and ATXN7L2 . These insights advance understanding of circadian preferences and suggest potential therapeutic interventions.

SIGNIFICANCE

This study investigates the genetic underpinnings of chronotype preferences and ease of getting up, with a focus on the orphan G protein-coupled receptor GPR61 and the locus lead variant rs12044778. By combining genomic data with in silico functional analysis, we provide mechanistic insight into a locus for morning chronotype and ease of getting in the morning. We identified the variant rs12044778 as a key regulator of GPR61 and nearby genes AMIGO1 and ATXN7L2 influencing circadian and metabolic traits. Our findings shed light on the intricate genetic networks governing circadian rhythms, suggesting potential therapeutic targets for disorders of the circadian rhythm.

Sleep Architecture Changes in Diabetes

Data on the relationship between sleep architecture and diabetes are limited. However, some evidence suggests that slow-wave sleep (SWS) plays a crucial role in maintaining normal glucose homeostasis and influences insulin secretion capacity. Diabetes is often associated with reduced SWS, even in the absence of sleep-disordered breathing. Notably, selective suppression of SWS-without reducing total sleep time-can lead to significant increases in insulin resistance, decreased glucose tolerance, and a higher risk of diabetes. Given the growing interest in non-pharmacological lifestyle interventions, such as modifying sleep architecture, it is important to understand how sleep patterns differ in individuals with diabetes and whether these alterations impact diabetes risk and glycemic control. This review aims to provide a concise overview of the current findings on sleep architecture changes in people with diabetes.

Sleep restriction reduces voluntary isometric quadriceps strength through reduced neuromuscular efficiency, not impaired contractile performance

Acute sleep restriction (SR) reduces strength through an unknown mechanism.

PURPOSE

To determine how SR affects quadriceps contractile function and recruitment.

METHODS

Eighteen healthy subjects (9 M, 9F, age 23.8 ± 2.8y) underwent isometric (maximal and submaximal), isokinetic (300-60°·s-1), and interpolated twitch (ITT) assessment of knee extensors following 3d of adequate sleep (SA; 7-9 h·night-1), 3d of SR (5 h·night-1), and 7d of washout (WO; 7-9 h·night-1).

RESULTS

Compared to SA (227.9 ± 76.6Nm) and WO (228.19 ± 62.9Nm), MVIC was lesser following SR (209.9 ± 73.9Nm; p = 0.006) and this effect was greater for males (- 9.8 v. - 4.8%). There was no significant effect of sleep or sleep x speed interaction on peak isokinetic torque. Peak twitch torque was greater in the potentiated state, but no significant effect of sleep was noted. Males displayed greater potentiation of peak twitch torque (12 v. 7.5%) and rate of torque development (16.7 v. 8.2%) than females but this was not affected by sleep condition. ITT-assessed voluntary activation did not vary among sleep conditions (SA: 81.8 ± 13.1% v. SR: 84.4 ± 12.6% v. WO 84.9 ± 12.6%; p = 0.093). SR induced a leftward shift in Torque-EMG relationship at high torque output in both sexes. Compared to SA, females displayed greater y-intercept and lesser slope with SR and WO and males displayed lesser y-intercept and greater slope with SR and WO.

CONCLUSIONS

Three nights of SR decreases voluntary isometric knee extensor strength, but not twitch contractile properties. Sex-specific differences in neuromuscular efficiency may explain the greater MVIC reduction in males following SR.

The Relationship Between Poor Sleep and Memory Impairment Among Shift Nurses in China: A Cross-Sectional Study

Purpose

Many shift nurses experience poor sleep quality, and the effect on nurses' cognitive function remains unclear. The study aims to investigate sleep status and explore its association with cognitive function.

Methods

This descriptive cross-sectional study was conducted in a tertiary care hospital in Fujian, China between March and September 2022. By convenience sampling method, 588 shift nurses participated in this study. The Pittsburgh Sleep Quality Index (PSQI) and Bergen Shift Work Sleep Questionnaire (BSWSQ) were used to assess sleep quality, while the Chinese version of Ascertain Dementia-8 (AD-8) was used to evaluate cognitive function. A PSQI score ≤7 is classified as good sleep quality, and a score >7 indicates poor sleep quality. An AD-8 score≥ 2 is considered indicative of memory impairment. Multivariate logistic regression analysis was conducted to explore the association between sleep status and memory impairment.

Results

A total of 310 (52.6%) participants presented poor sleep quality. Among them, 52.2% of participants had day shift-related sleep problems, 45.9% had evening shift-related sleep problems, 61.9% had night shift-related sleep problems, and 15.0% reported rest-day/vacation-related sleep problems. The prevalence of poor sleep quality and each shift-related sleep problem in the memory impairment group were higher than in the normal memory group (P<0.05). Multivariate logistic regression analysis indicated that poor sleep quality (OR=2.073, 95% CI: 1.398~3.072), evening shift-related sleep problems (OR=1.707, 95% CI: 1.028~2.835), night shift-related sleep problems (OR=1.859, 95% CI:1.104~3.129), and rest-day/vacation-related sleep problems (OR=2.069, 95% CI:1.170~3.659) was significantly associated with memory impairment.

Conclusion

This study highlights the prevalence of poor sleep quality among clinical nurses and identifies poor sleep quality and shift-related sleep problems (excluding day shift) as risk factors for memory impairment. Nurse managers should prioritize sleep quality and focus on cognitive function to enhance nurses' occupational health.

Lifestyle and cardiovascular risk in working young adults: insights from a nationwide Spanish cohort

INTRODUCTION AND OBJECTIVES

This study aimed to describe the cardiovascular risk profile of working young adults from Spain and its association with lifestyle.

METHODS

Participants (18-30 years) were recruited from a nationwide cohort of economically active adults insured by a large occupational risk prevention company, with data obtained from routine medical assessments. The participants were categorized as having an "unhealthy" cardiovascular risk profile based on the presence of prediabetes/diabetes, prehypertension/hypertension, or hypercholesterolemia, or a "healthy" profile if these conditions were completely absent. The association with lifestyle factors (weight, physical activity, sleeping characteristics, alcohol consumption, smoking) was assessed.

RESULTS

A total of 78 421 young adults (27±2 years, 36% female) were evaluated at baseline. The "unhealthy" cardiovascular risk profile was prevalent (18%) and inversely associated (OR, 0.64; 95%CI, 0.57-0.80) with an optimal lifestyle (normal weight, regular physical activity, no drinking/smoking, and good sleep). The latter condition was found in only 3.5% of the participants. On the other hand, prospective analyses in 44 776 participants (median follow-up=2 [range 2-5] years) showed that 2.0% transitioned from a "healthy" to an "unhealthy" profile. Being physically active (OR, 0.95; 95%CI, 0.81-0.99) and having a normal weight (OR, 0.61; 95%CI, 0.51-0.70) were associated with a lower likelihood of this transition. No consistent associations were found for other lifestyle factors.

CONCLUSIONS

The prevalence of cardiovascular risk factors is high in economically active young Spanish adults. An unhealthy cardiovascular risk profile is inversely associated with an optimal lifestyle, but the latter is highly infrequent in this population.

Combined effects of sleep timing and nighttime sleep duration on non-alcoholic fatty liver disease

BACKGROUND

While short sleep duration is linked to higher risk of non-alcoholic fatty liver disease (NAFLD), the combined effects of sleep timing and sleep duration on NAFLD are less explored.

METHODS

In this cross-sectional study of 39,471 participants from Beijing-Tianjin-Hebei region of China, self-reported sleep information and ultrasonography-diagnosed NAFLD were obtained from Jan 2018 to Jan 2020. Sleep timing was categorized based on sleep midpoint: early-type (before 2:00 AM), intermediate-type (2:00-2:30 AM), and late-type (after 2:30 AM). We used multivariable logistic regression to explore the relationship between sleep timing, duration, and NAFLD. We analyzed sleep midpoint and duration categorically and continuously, and conducted stratification analyses by age, sex, body mass index, hypertension, diabetes, and dyslipidemia.

RESULTS

Intermediate-type (OR: 1.15, 95% confidence interval: 1.05-1.26) and late-type sleep timing (OR: 1.08, 1.00-1.16) were associated with higher NAFLD risk compared to early-type. Additionally, longer sleep duration was linked to lower risk (OR: 0.92, 0.90-0.95 per hour increase). Notably, intermediate to late-type sleepers with normal sleep duration (7 to <8 h) exhibited a 20% higher NAFLD risk compared to early-type sleepers with the same duration (OR: 1.20, 1.04-1.39). The increased NAFLD risk associated with intermediate to late sleep timing was particularly evident in men, hypertension, and prediabetes or diabetes participants.

CONCLUSIONS

Intermediate to late sleep timing, even with normal sleep duration, is associated with increased NAFLD risk. These findings underscore the importance of considering both sleep timing and sleep duration for NAFLD prevention, especially in men and individuals with cardiometabolic conditions.

Sleep duration, overweight status, and the modifying role of food insecurity in a sample of 10- to 14-year-old Mexican early adolescents

OBJECTIVES

Short sleep duration has been associated with an increased risk of childhood overweight and obesity in high-income countries, but data from low- and middle-income countries are scarce. Independently, short sleep and food insecurity may increase the risk of overweight/obesity, but it is unknown whether they concurrently affect it.

METHODS

We included 3350 adolescents aged 10-14 from the 2012 and 2016 Mexican National Health and Nutrition Survey. Short sleep was categorized as less than 9 hours for ages 10-12 and less than 8 hours for ages 13-14. Overweight/obesity was assessed via anthropometry. Modified Poisson regression models assessed prevalence ratios between short sleep and overweight, examining effect modification by food security status.

RESULTS

86% met sleep duration recommendations. Short sleep was associated with an increased prevalence of overweight/obesity (prevalence ratio, 1.16; 95% CI, 1.05, 1.31). Multiplicative interaction was found between low and very low food security status and short sleep: adolescents in low food secure households with short sleep had 1.38 (95% CI: 1.10, 1.75) times the prevalence of overweight/obesity compared to adequate sleepers. Very low food secure households had 1.16 (95% CI: 1.14, 1.31) times the prevalence compared to adequate sleepers. This association was not significant in fully or marginally food secure households.

CONCLUSIONS

Short sleep is associated with an increased obesity risk among Mexican adolescents 10-14years, particularly in the context of low and very low food security. These findings highlight the importance of addressing both sleep hygiene and food security in strategies to reduce obesity risk.

Genetic variants affect diurnal glucose levels throughout the day

Circadian rhythms not only coordinate the timing of wake and sleep but also regulate homeostasis within the body, including glucose metabolism. However, the genetic variants that contribute to temporal control of glucose levels have not been previously examined. Using data from 420,000 individuals from the UK Biobank and replicating our findings in 100,000 individuals from the Estonian Biobank, we show that diurnal serum glucose is under genetic control. We discover a robust temporal association of glucose levels at the Melatonin receptor 1B ( MTNR1B) (rs10830963, P = 1e-22) and a canonical circadian pacemaker gene Cryptochrome 2 ( CRY2) loci (rs12419690, P = 1e-16). Furthermore, we show that sleep modulates serum glucose levels and the genetic variants have a separate mechanism of diurnal control. Finally, we show that these variants independently modulate risk of type 2 diabetes. Our findings, together with earlier genetic and epidemiological evidence, show a clear connection between sleep and metabolism and highlight variation at MTNR1B and CRY2 as temporal regulators for glucose levels.

Saturation effects of the relationship between physical exercise and systemic immune inflammation index in the short-sleep population: a cross-sectional study

BACKGROUND

Short sleep can lead to an increase in inflammation and regular exercise has been shown to have a mitigation effect. However, the association between physical exercise (PE) and inflammation in the short sleep population is an unknown and intriguing issue.

METHODS

NHANES dataset spanning the years 2007 to 2018 were analyzed. To investigate the relationship mentioned above, we carried out multivariate linear regression models controlling for sociodemographic and lifestyles factors. The systemic immune inflammation index (SII) served as a reflection of inflammatory potential, calculated as the product of platelet count, neutrophil count, and divided by the lymphocyte count. Self-reported questionnaires were used to collect sleep and exercise information.

RESULTS

A total of 14,664 participants were included for final analysis. Across the three models, PE showed significant negative associations with SII as a continuous variable [Crude Model, β (95% CI): -1.261(-1.600, -0.922), p < 0.001; Model 1, β (95% CI): -1.005(-1.344, -0.666), p < 0.001; Model 2, β (95% CI): -0.470(-0.827, -0.112), p = 0.011]. The consistent nature of the findings persisted when investigating physical exercise (PE) as a categorized variable. By two-piecewise linear regression model, we calculated a saturation effect of PE with the inflection point as 2400 MET-minutes/week.

CONCLUSION

This study suggested that performing no more than 2400 MET-minutes/week of PE was associated with lower SII levels in the short sleep population, while more PE might not bring additional benefits.

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.

Energy Deficit is a Key Driver of Sleep Homeostasis

Sleep and feeding are vital homeostatic behaviors, and disruptions in either can result in substantial metabolic consequences. Distinct neuronal manipulations in Drosophila can dissociate sleep loss from subsequent homeostatic rebound, offering an optimal platform to examine the precise interplay between these fundamental behaviors. Here, we investigate concomitant changes in sleep and food intake in individual animals, as well as respiratory metabolic expenditure, that accompany behavioral and genetic manipulations that induce sleep loss in Drosophila melanogaster. We find that sleep disruptions resulting in energy deficit through increased metabolic expenditure and manifested as increased food intake were consistently followed by rebound sleep. In contrast, "soft" sleep loss, which does not induce rebound sleep, is not accompanied by increased metabolism and food intake. Our results demonstrate that homeostatic sleep rebound is linked to energy deficit accrued during sleep loss. Collectively, these findings support the notion that sleep functions to conserve energy and highlight the need to examine the effects of metabolic therapeutics on sleep.

Associations of Subjective Sleep Quality with Wearable Device-Derived Resting Heart Rate During REM Sleep and Non-REM Sleep in a Cohort of Japanese Office Workers

Background

Associations between subjective sleep quality and stage-specific heart rate (HR) may have important clinical relevance when aiming to optimize sleep and overall health. The majority of previously studies have been performed during short periods under laboratory-based conditions. The aim of this study was to investigate the associations of subjective sleep quality with heart rate during REM sleep (HR REMS) and non-REM sleep (HR NREMS) using a wearable device (Fitbit Versa).

Methods

This is a secondary analysis of data from the intervention group of a randomized controlled trial (RCT) performed between December 3, 2018, and March 2, 2019, in Tokyo, Japan. The intervention group consisted of 179 Japanese office workers with metabolic syndrome (MetS), Pre-MetS or a high risk of developing MetS. HR was collected with a wearable device and sleep quality was assessed with a mobile application where participants answered The St. Mary's Hospital Sleep Questionnaire. Both HR and sleep quality was collected daily for a period of 90 days. Associations of between-individual and within-individual sleep quality with HR REMS and HR NREMS were analyzed with multi-level model regression in 3 multivariate models.

Results

The cohort consisted of 92.6% men (n=151) with a mean age (± standard deviation) of 44.1 (±7.5) years. A non-significant inverse between-individual association was observed for sleep quality with HR REMS (HR REMS -0.18; 95% CI -0.61, 0.24) and HR NREMS (HR NREMS -0.23; 95% CI -0.66, 0.21), in the final multivariable adjusted models; a statistically significant inverse within-individual association was observed for sleep quality with HR REMS (HR REMS -0.21 95% CI -0.27, -0.15) and HR NREMS (HR NREMS -0.21 95% CI -0.27, -0.14) after final adjustments for covariates.

Conclusion

The present study shows a statistically significant within-individual association of subjective sleep quality with HR REMS and HR NREMS. These findings emphasize the importance of considering sleep quality on the individual level. The results may contribute to early detection and prevention of diseases associated with sleep quality which may have important implications on public health given the high prevalence of sleep disturbances in the population.

Association between sarcopenia and sleep disorders: a cross-sectional population based study

Objective

Sleep disorders is a worldwide public health problem. We sought to examine the association between sarcopenia, a decline in skeletal muscle mass and function, and sleep disorders within the adult demographic of the United States during the period spanning 2011 to 2018.

Methods

Diagnosis of sarcopenia and sleep disorders was ascertained through appropriate calculations and a structured questionnaire. The primary correlation analysis was conducted using a weighted multivariate logistic regression model. Furthermore, to confirm the presence of a potential non-linear association between sarcopenia and sleep disorders, additional analyses were performed using multivariate logistic regression and restricted cubic spline (RCS) regression with dose-response curve analysis. Subgroup analyses were also conducted to explore the influence of relevant socio-demographic factors and other covariates.

Results

The final analysis encompassed 5,616 participants. Model 4, inclusive of all pertinent covariates, revealed a positive correlation between sarcopenia and sleep disorders, yielding an odds ratio (OR) of 1.732 (95% CI: 1.182-2.547; P = 0.002). Further analysis, utilizing the restricted cubic spline model, indicated a decreasing trend in sleep disorders as sarcopenia indices rose. Stratified analyses across diverse variables underscored the significant impact of sarcopenia on sleep disorders prevalence in several subgroups. Specifically, males, individuals aged 40 and above, non-Hispanic whites, those with high school education or equivalent, unmarried individuals, obese individuals (BMI ≥ 30), alcohol drinkers, former smokers, diabetics, and those engaging in less rigorous recreational activities exhibited a more pronounced association between sarcopenia and sleep disorders. The incidence of sleep disorders exhibited an upward trend as the incidence of sarcopenia declined among study participants.

Conclusions

In summary, our study provides evidence of an association between sarcopenia and the prevalence of sleep disorders, with a negative correlation observed between the sarcopenia index and the odds ratio of sleep disorders. These findings suggest that maintaining optimal muscle mass may have a beneficial impact on sleep-related issues. In terms of exploring the mechanisms underlying the relationship between sarcopenia and sleep disorders, more in-depth research is warranted to ascertain the definitive causal relationship.

Molecular mechanisms linking type 2 diabetes mellitus and late-onset Alzheimer's disease: A systematic review and qualitative meta-analysis

Research evidence indicating common metabolic mechanisms through which type 2 diabetes mellitus (T2DM) increases risk of late-onset Alzheimer's dementia (LOAD) has accumulated over recent decades. The aim of this systematic review is to provide a comprehensive review of common mechanisms, which have hitherto been discussed in separate perspectives, and to assemble and evaluate candidate loci and epigenetic modifications contributing to polygenic risk linkages between T2DM and LOAD. For the systematic review on pathophysiological mechanisms, both human and animal studies up to December 2023 are included. For the qualitative meta-analysis of genomic bases, human association studies were examined; for epigenetic mechanisms, data from human studies and animal models were accepted. Papers describing pathophysiological studies were identified in databases, and further literature gathered from cited work. For genomic and epigenomic studies, literature mining was conducted by formalised search codes using Boolean operators in search engines, and augmented by GeneRif citations in Entrez Gene, and other sources (WikiGenes, etc.). For the systematic review of pathophysiological mechanisms, 923 publications were evaluated, and 138 gene loci extracted for testing candidate risk linkages. 3 57 publications were evaluated for genomic association and descriptions of epigenomic modifications. Overall accumulated results highlight insulin signalling, inflammation and inflammasome pathways, proteolysis, gluconeogenesis and glycolysis, glycosylation, lipoprotein metabolism and oxidation, cell cycle regulation or survival, autophagic-lysosomal pathways, and energy. Documented findings suggest interplay between brain insulin resistance, neuroinflammation, insult compensatory mechanisms, and peripheral metabolic dysregulation in T2DM and LOAD linkage. The results allow for more streamlined longitudinal studies of T2DM-LOAD risk linkages.

Gender-specific link between sleep quality and body composition components: a cross-sectional study on the elderly

Sleep duration has been associated with overweight/obesity. Since sleep quality and body composition alter during aging, we conducted this study to determine if sleep quality is linked to body composition components in elderly people. This is a cross-sectional study conducted on 305 Iranian community-dwelling elderly aged ≥ 65 years. Sleep quality and body composition components were evaluated using Pittsburgh sleep quality index and bioelectric impedance analysis, respectively. The association of sleep quality and body composition components was examined using linear regression analysis. The prevalence of poor sleep quality and overweight/obesity was 48.9% and 54.4% in men and 77.0% and 79.3% in women, respectively. Women had significantly higher scores in most PSQI items than men, indicating their worse sleep quality compared to men. Women also had significantly higher body mass index (BMI), body fat percentage, and visceral adipose tissue and lower skeletal muscle and fat-free mass percentages than men. In the adjusted regression model, men showed positive associations between the third tertile of poor sleep quality and BMI (B = 1.35; 95% CI 0.08-2.61) and waist circumference (B = 4.14; 95% CI 0.39-7.89), but they did not demonstrate an association between sleep quality and body composition components. In the adjusted regression model for women, there were positive associations for BMI (B = 1.21; 95% CI 0.34-2.07), waist circumference (B = 2.95; 95% CI 0.99-4.91), body fat percentage (B = 2.75; 95% CI 1.06-4.45), and visceral adipose tissue (B = 7.80; 95% CI 1.73-13.87); also there were negative associations for skeletal muscle (B =  - 1.40; 95% CI - 2.39 - - 0.41) and fat-free mass (B =  - 2.76; 95% CI - 4.46 - -1.07) percentages. Except for waist circumference, other variables differed between men and women (P < 0.001). Weight management, prevention of muscle wasting, and improvement of sleep quality should be considered in a consortium when designing healthcare strategies for the elderly.

Associations between sleep-behavioral traits and healthspan: A one-sample Mendelian randomization study based on 388,909 participants of the UK-Biobank

BACKGROUND

Although the association between sleep behavior and morbidity and mortality risk has been reported before, there is still uncertainty whether the observed associations are causal or confounding. Therefore, we investigated the causal relationships between sleep-behavioral traits and terminated healthspan risk using Mendelian randomization (MR).

METHODS

We conducted a one-sample MR analysis to evaluate causality between six sleep-behavioral traits (sleep duration, chronotype/morningness, napping, sleeplessness/insomnia, and getting up from bed) and risk of healthspan termination among 388, 909 UK Biobank (UKB) participants. Instrumental variables for sleep behaviors (N = 590) were obtained from recent genome-wide association studies (GWAS). We defined healthspan based on eight predominant health-terminating events associated with longevity (congestive heart failure, myocardial infarction, chronic obstructive pulmonary disease, stroke, dementia, diabetes, cancer, and death). We further constructed a sleep score and a weighted genetic risk score to increase the predictive ability of the sleep-behavioral traits. Cox regression models and Inverse Probability Treatment Weighting (IPTW) were implemented, followed by MR to assess causation. We used inverse-variance-weighted MR to estimate causal effects, and weighted-median and MR-egger for sensitivity analysis to test the pleiotropic effects.

RESULTS

In IPTW, we observed a decreased risk of terminated healthspan for healthy sleep behaviors such as 'sleep duration 7-8h/d' (Hazard ratio, HR = 0.93; 95 % confidence interval, CI: 0.92-0.96; P < 0.001); 'morningness' (HR = 0.95; 95%CI: 0.93-0.98; P < 0.01); 'napping' (HR = 0.93; 95%CI: 0.91-0.94; P < 0.001); 'easy getting up from bed' (HR = 0.91; 95%CI: 0.88-0.93; P < 0.001); and, 'never/rarely experience sleeplessness/insomnia' (HR = 0.94; 95%CI: 0.92-0.96; P < 0.001). MR results further indicated causal associations between healthy sleep duration (OR = 0.98; 95%CI: 0.97-1.00; P = 0.036) and insomnia (OR = 1.02; 95%CI: 1.01-1.03; P < 0.001) with terminated healthspan. MR-egger did not suggest any potential pleiotropy.

CONCLUSION

This study supports abnormal sleep duration and insomnia as potential causal risk factors for terminated healthspan. Thus, healthy sleep behavior is valuable for the extension of healthspan, and well-designed and tailored sleep health interventions are warranted.

Hypoglycemia Unawareness-A Review on Pathophysiology and Clinical Implications

Hypoglycemia is a particular problem in people with diabetes while it can also occur in other clinical circumstances. Hypoglycemia unawareness describes a condition in which autonomic and neuroglycopenic symptoms of hypoglycemia decrease and hence are hardly perceivable. A failure to recognize hypoglycemia in time can lead to unconsciousness, seizure, and even death. The risk factors include intensive glycemic control, prior episodes of severe hypoglycemia, long duration of diabetes, alcohol consumption, exercise, renal failure, and sepsis. The pathophysiological mechanisms are manifold, but mainly concern altered brain glucose sensing, cerebral adaptations, and an impaired hormonal counterregulation with an attenuated release of glucagon, epinephrine, growth hormone, and other hormones, as well as impaired autonomous and neuroglycopenic symptoms. Physiologically, this counterregulatory response causes blood glucose levels to rise. The impaired hormonal counterregulatory response to recurrent hypoglycemia can lead to a vicious cycle of frequent and poorly recognized hypoglycemic episodes. There is a shift in glycemic threshold to trigger hormonal counterregulation, resulting in hypoglycemia-associated autonomic failure and leading to the clinical syndrome of hypoglycemia unawareness. This clinical syndrome represents a particularly great challenge in diabetes treatment and, thus, prevention of hypoglycemia is crucial in diabetes management. This mini-review provides an overview of hypoglycemia and the associated severe complication of impaired hypoglycemia awareness and its symptoms, pathophysiology, risk factors, consequences, as well as therapeutic strategies.

Sex and Sleep Disruption as Contributing Factors in Alzheimer's Disease

Alzheimer's disease (AD) affects more women than men, with women throughout the menopausal transition potentially being the most under researched and at-risk group. Sleep disruptions, which are an established risk factor for AD, increase in prevalence with normal aging and are exacerbated in women during menopause. Sex differences showing more disrupted sleep patterns and increased AD pathology in women and female animal models have been established in literature, with much emphasis placed on loss of circulating gonadal hormones with age. Interestingly, increases in gonadotropins such as follicle stimulating hormone are emerging to be a major contributor to AD pathogenesis and may also play a role in sleep disruption, perhaps in combination with other lesser studied hormones. Several sleep influencing regions of the brain appear to be affected early in AD progression and some may exhibit sexual dimorphisms that may contribute to increased sleep disruptions in women with age. Additionally, some of the most common sleep disorders, as well as multiple health conditions that impair sleep quality, are more prevalent and more severe in women. These conditions are often comorbid with AD and have bi-directional relationships that contribute synergistically to cognitive decline and neuropathology. The association during aging of increased sleep disruption and sleep disorders, dramatic hormonal changes during and after menopause, and increased AD pathology may be interacting and contributing factors that lead to the increased number of women living with AD.

The Causal Relationship between the Morning Chronotype and the Gut Microbiota: A Bidirectional Two-Sample Mendelian Randomization Study

BACKGROUND

Numerous observational studies have documented an association between the circadian rhythm and the composition of the gut microbiota. However, the bidirectional causal effect of the morning chronotype on the gut microbiota is unknown.

METHODS

A two-sample Mendelian randomization study was performed, using the summary statistics of the morning chronotype from the European Consortium and those of the gut microbiota from the largest available genome-wide association study meta-analysis, conducted by the MiBioGen consortium. The inverse variance-weighted (IVW), weighted mode, weighted median, MR-Egger regression, and simple mode methods were used to examine the causal association between the morning chronotype and the gut microbiota. A reverse Mendelian randomization analysis was conducted on the gut microbiota, which was identified as causally linked to the morning chronotype in the initial Mendelian randomization analysis. Cochran's Q statistics were employed to assess the heterogeneity of the instrumental variables.

RESULTS

Inverse variance-weighted estimates suggested that the morning chronotype had a protective effect on Family Bacteroidaceae (β = -0.072; 95% CI: -0.143, -0.001; p = 0.047), Genus Parabacteroides (β = -0.112; 95% CI: -0.184, -0.039; p = 0.002), and Genus Bacteroides (β = -0.072; 95% CI: -0.143, -0.001; p = 0.047). In addition, the gut microbiota (Family Bacteroidaceae (OR = 0.925; 95% CI: 0.857, 0.999; p = 0.047), Genus Parabacteroides (OR = 0.915; 95% CI: 0.858, 0.975; p = 0.007), and Genus Bacteroides (OR = 0.925; 95% CI: 0.857, 0.999; p = 0.047)) demonstrated positive effects on the morning chronotype. No significant heterogeneity in the instrumental variables, or in horizontal pleiotropy, was found.

CONCLUSION

This two-sample Mendelian randomization study found that Family Bacteroidaceae, Genus Parabacteroides, and Genus Bacteroides were causally associated with the morning chronotype. Further randomized controlled trials are needed to clarify the effects of the gut microbiota on the morning chronotype, as well as their specific protective mechanisms.

Exercise to prevent the negative effects of sleep deprivation: A systematic review and meta-analysis

Ample sleep is an important basis for maintaining health, however with the pace of life accelerating in modern society, more people are using sacrificial sleep to cope with these social changes. Sleep deprivation can have negative effects on cognitive performance and psychosomatic health. It is well known that exercise, as a beneficial intervention strategy for human health, has been increasingly used in the clinic. But it's not clear if it can prevent the negative effects of sleep deprivation. In this meta-analysis, we reviewed 23 articles from PubMed and Web of Science to investigate whether moderate physical exercise can prevent the negative effects of sleep deprivation in rodents. Our findings suggest that exercise can prevent sleep deprivation-induced cognitive impairment and anxiety-like behaviors through multiple pathways. We also discuss possible molecular mechanisms involved in this protective effect, highlighting the potential of exercise as a preventive or therapeutic strategy for sleep deprivation-induced negative effects.

Effect of Cognitive Behavioural Therapy in Improving Sleep and Health Status in Patients with Cardiometabolic Syndrome: a Meta-Analysis

The aim of this study was to assess the effect of cognitive behavioural therapy intervention on sleep and health improvement in patients with cardiometabolic syndrome and sleep problems. This study also aimed to assess the effect of different study designs to explain the overall intervention effect through subgroup analysis. Relevant randomized controlled trial studies were searched through six online databases. The PEDro scale was used to assess the quality of the included studies. The random effects model was used to assess the mean difference, effect size, and standard deviation of the outcome variables. The heterogeneity of the included studies was assessed using I2 and Q tests. Publication bias was assessed by the Egger test. Cognitive behavioural therapy intervention provided a significant effect in improving the Pittsburgh Sleep Quality Index, Insomnia Severity Index, total sleep time, sleep efficiency, depression, fatigue, and HbA1c. The effect of cognitive behavioural therapy is more significant when relaxation training and education components are included. Cognitive behavioural therapy is suitable for the treatment of sleep problems in patients with cardiometabolic syndrome. Cognitive behavioural therapy is also effective on depression and fatigue but has a limited effect on blood pressure and biomedical indicators related to cardiometabolic syndrome.

Sleep deprivation and aging are metabolically linked across tissues

STUDY OBJECTIVES

Insufficient sleep is a concerning hallmark of modern society because sleep deprivation (SD) is a risk factor for neurodegenerative and cardiometabolic disorders. SD imparts an aging-like effect on learning and memory, although little is known about possible common molecular underpinnings of SD and aging. Here, we examine this question by profiling metabolic features across different tissues after acute SD in young adult and aged mice.

METHODS

Young adult and aged mice were subjected to acute SD for 5 hours. Blood plasma, hippocampus, and liver samples were subjected to UPLC-MS/MS-based metabolic profiling.

RESULTS

SD preferentially impacts peripheral plasma and liver profiles (e.g. ketone body metabolism) whereas the hippocampus is more impacted by aging. We further demonstrate that aged animals exhibit SD-like metabolic features at baseline. Hepatic alterations include parallel changes in nicotinamide metabolism between aging and SD in young animals. Overall, metabolism in young adult animals is more impacted by SD, which in turn induces aging-like features. A set of nine metabolites was classified (79% correct) based on age and sleep status across all four groups.

CONCLUSIONS

Our metabolic observations demonstrate striking parallels to previous observations in studies of learning and memory and define a molecular metabolic signature of sleep loss and aging.

Effects of Healthy Lifestyles on Chronic Diseases: Diet, Sleep and Exercise

Among the many factors affecting general health and resilience to disease, lifestyle is at the same time the most controllable and the most influential factor [...].

Association of poor sleep and HbA1c in metformin-treated patients with type 2 diabetes: Findings from the UK Biobank cohort study

The American Diabetes Association recommends a glycated haemoglobin target of less than 7% for treating type 2 diabetes mellitus. However, it is still being determined if poor sleep affects this therapeutic goal, despite being treated with the blood-glucose-lowering medication metformin. Thus, we used data from 5703 patients on metformin monotherapy participating in the UK Biobank baseline investigation between 2006 and 2010. We combined self-reported chronotype, daily sleep duration, insomnia, daytime sleepiness and snoring into a multidimensional poor sleep score ranging from 0 to 5, with higher scores indicating a less healthy sleep pattern. With each point increase on the poor sleep score scale, the odds of patients having an glycated haemoglobin of ≥ 7% increased by 6% (odds ratio [95% confidence interval], 1.06 [1.01, 1.11], p = 0.021). When examining the components of the poor sleep score separately, snoring was specifically associated with a glycated haemoglobin of ≥ 7% (1.12 [1.01, 1.25] versus no snoring, p = 0.038). However, adjusting for health and lifestyle conditions, such as body mass index, weekly physical activity level and hypertension status, eliminated the significant associations between the poor sleep score and snoring with glycated haemoglobin of ≥ 7%. Our findings suggest that poor sleep, specifically snoring, a symptom of obstructive sleep apnea, may interfere with the therapeutic goal of achieving a glycated haemoglobin below 7%. However, other factors known to be promoted by poor sleep, such as high body mass index, low physical activity and hypertension, may also contribute to the link between poor sleep and higher glycated haemoglobin levels.

Sleep Duration and Stress Level in the Risk of Gastric Cancer: A Pooled Analysis of Case-Control Studies in the Stomach Cancer Pooling (StoP) Project

The association between sleep and stress and cancer is underinvestigated. We evaluated these factors in association with gastric cancer (GC). Five case-control studies from the Stomach Cancer Pooling (StoP) Project were included. We calculated the odds ratios (ORs) and the corresponding 95% confidence intervals (CIs) for sleep duration and stress level in association with GC through multiple logistic regression models adjusted for several lifestyle factors. The analysis included 1293 cases and 4439 controls, 215 cardia and 919 noncardia GC, and 353 diffuse and 619 intestinal types. Sleep duration of ≥9 h was associated with GC (OR =1.57, 95% CI = 1.23-2.00) compared to 8 h. This was confirmed when stratifying by subsite (noncardia OR = 1.59, 95% CI = 1.22-2.08, and cardia OR = 1.63, 95% CI = 0.97-2.72) and histological type (diffuse OR = 1.65, 95% CI = 1.14-2.40 and intestinal OR = 1.24, 95% CI = 0.91-1.67). Stress was associated with GC (OR = 1.33, 95% CI = 1.18-1.50, continuous). This relationship was selectively related to noncardia GC (OR = 1.28, 95% 1.12-1.46, continuous). The risk of diffuse (OR = 1.32, 95% CI = 1.11-1.58) and intestinal type (OR = 1.23, 95% CI = 1.07-1.42) were higher when stress was reported. Results for the association between increasing level of stress and GC were heterogeneous by smoking and socioeconomic status (p for heterogeneity = 0.02 and <0.001, respectively). In conclusion, long sleep duration (≥9 h) was associated with GC and its subtype categories. Stress linearly increased the risk of GC and was related to noncardia GC.

Associations of Insomnia With Insulin Resistance Traits: A Cross-sectional and Mendelian Randomization Study

CONTEXT

Insomnia is associated with insulin resistance (IR) in observational studies; however, whether insomnia is causally associated with IR remains unestablished.

OBJECTIVE

This study aims to estimate the causal associations of insomnia with IR and its related traits.

METHODS

In primary analyses, multivariable regression (MVR) and 1-sample Mendelian randomization (1SMR) analyses were performed to estimate the associations of insomnia with IR (triglyceride-glucose index and triglyceride to high-density lipoprotein cholesterol [TG/HDL-C] ratio) and its related traits (glucose level, TG, and HDL-C) in the UK Biobank. Thereafter, 2-sample MR (2SMR) analyses were used to validate the findings from primary analyses. Finally, the potential mediating effects of IR on the pathway of insomnia giving rise to type 2 diabetes (T2D) were examined using a 2-step MR design.

RESULTS

Across the MVR, 1SMR, and their sensitivity analyses, we found consistent evidence suggesting that more frequent insomnia symptoms were significantly associated with higher values of triglyceride-glucose index (MVR, β = 0.024, P < 2.00E-16; 1SMR, β = 0.343, P < 2.00E-16), TG/HDL-C ratio (MVR, β = 0.016, P = 1.75E-13; 1SMR, β = 0.445, P < 2.00E-16), and TG level (MVR, β = 0.019 log mg/dL, P < 2.00E-16, 1SMR: β = 0.289 log mg/dL, P < 2.00E-16) after Bonferroni adjustment. Similar evidence was obtained by using 2SMR, and mediation analysis suggested that about one-quarter (25.21%) of the association between insomnia symptoms and T2D was mediated by IR.

CONCLUSIONS

This study provides robust evidence supporting that more frequent insomnia symptoms are associated with IR and its related traits across different angles. These findings indicate that insomnia symptoms can be served as a promising target to improve IR and prevent subsequent T2D.

Coordinated human sleeping brainwaves map peripheral body glucose homeostasis

Insufficient sleep impairs glucose regulation, increasing the risk of diabetes. However, what it is about the human sleeping brain that regulates blood sugar remains unknown. In an examination of over 600 humans, we demonstrate that the coupling of non-rapid eye movement (NREM) sleep spindles and slow oscillations the night before is associated with improved next-day peripheral glucose control. We further show that this sleep-associated glucose pathway may influence glycemic status through altered insulin sensitivity, rather than through altered pancreatic beta cell function. Moreover, we replicate these associations in an independent dataset of over 1,900 adults. Of therapeutic significance, the coupling between slow oscillations and spindles was the most significant sleep predictor of next-day fasting glucose, even more so than traditional sleep markers, relevant to the possibility of an electroencephalogram (EEG) index of hyperglycemia. Taken together, these findings describe a sleeping-brain-body framework of optimal human glucose homeostasis, offering a potential prognostic sleep signature of glycemic control.

Sleep, 24-hour activity rhythms, and cardiometabolic risk factors in school-age children

STUDY OBJECTIVES

Disturbed sleep and 24-hour activity rhythms are linked to adverse cardiometabolic profiles in adults and adolescents, and these associations may originate in early life. We aimed to study associations of sleep and 24-hour rhythms with cardiometabolic risk factors in school-age children.

METHODS

This cross-sectional population-based study comprised 894 children aged 8-11 years from the Generation R Study. Sleep (duration, efficiency, number of awakenings, and time awake after sleep onset) and 24-hour activity rhythms (social jet lag, interdaily stability, and intradaily variability) were assessed using triaxial wrist actigraphy for 9 consecutive nights. Cardiometabolic risk factors included adiposity (body mass index Z-score, fat mass index using dual-energy X-ray absorptiometry, and visceral fat mass and liver fat fraction using magnetic resonance imaging), blood pressure, and blood markers (glucose, insulin, and lipids). We adjusted for season, age, sociodemographics, and lifestyle factors.

RESULTS

Each increase in interquartile range of nightly awakenings (2 times) was associated with -0.12 standard deviation (95% confidence interval: -0.21, -0.04) lower body mass index and 0.15 mmol/L (0.10, 0.21) higher glucose. Among boys, an increase in interquartile range of intradaily variability (0.12) was associated with higher fat mass index (+0.07 kg/m2; 95% confidence interval: 0.03, 0.11) and visceral FM (+0.08 g; 95% confidence interval: 0.02, 0.15). We observed no associations with blood pressure or clustering of cardiometabolic risk factors.

CONCLUSIONS

Already at school age, greater fragmentation of the 24-hour activity rhythm is associated with general and organ adiposity. In contrast, more nightly awakenings were associated with lower body mass index. Future research should bring clarity to these disparate observations in order to create potential targets for obesity prevention programs.

CITATION

Beunders VAA, Koopman-Verhoeff ME, Vermeulen MJ, et al. Sleep, 24-hour activity rhythms, and cardiometabolic risk factors in school-age children. J Clin Sleep Med. 2023;19(7):1219-1229.

Detrimental Changes in Health during Menopause: The Role of Physical Activity

Midlife women experience changes in cardiometabolic, physical, and psychosocial health during menopause that negatively impacts their overall quality of life. Factors that contribute to these increases in cardiometabolic risk include weight gain as well as increases in fat mass (particularly abdominal adiposity), insulin resistance, and vascular dysfunction. Other deleterious changes in physical health (e. g. reduced sleep health, bone density, and balance) as well as changes in psychosocial health (e. g. mood, anxiety, and depression) often coincide and are linked to these increases in cardiometabolic risk. Physical activity and exercise are important lifestyle components that have been demonstrated to improve cardiometabolic, physical, and psychosocial health, yet physical activity and exercise is known to decline during perimenopause and into the postmenopausal years. In this narrative review, we summarize these changes in overall health during menopause as well as how declining physical activity contributes to these changes. Additionally, we discuss how incorporating physical activity and exercise during menopause can potentially ameliorate health declines. We conclude that there exists a significant, positive impact of physical activity on cardiometabolic, physical, and psychological health among midlife women, particularly if undertaken during the perimenopausal and postmenopausal years.

Late, but Not Early, Night Sleep Loss Compromises Neuroendocrine Appetite Regulation and the Desire for Food

OBJECTIVE

There is evidence that reduced sleep duration increases hunger, appetite, and food intake, leading to metabolic diseases, such as type 2 diabetes and obesity. However, the impact of sleep timing, irrespective of its duration and on the regulation of hunger and appetite, is less clear. We aimed to evaluate the impact of sleep loss during the late vs. early part of the night on the regulation of hunger, appetite, and desire for food.

METHODS

Fifteen normal-weight ([mean ± SEM] body-mass index: 23.3 ± 0.4 kg/m²) healthy men were studied in a randomized, balanced, crossover design, including two conditions of sleep loss, i.e., 4 h sleep during the first night-half ('late-night sleep loss'), 4 h sleep during the second night-half ('early-night sleep loss'), and a control condition with 8h sleep ('regular sleep'), respectively. Feelings of hunger and appetite were assessed through visual analogue scales, and plasma ghrelin and leptin were measured from blood samples taken before, during, and after night-time sleep.

RESULTS

Ghrelin and feelings of hunger and appetite, as well as the desire for food, were increased after 'late-night sleep loss', but not 'early-night sleep loss', whereas leptin remained unaffected by the timing of sleep loss.

CONCLUSIONS

Our data indicate that timing of sleep restriction modulates the effects of acute sleep loss on ghrelin and appetite regulation in healthy men. 'Late-night sleep loss' might be a risk factor for metabolic diseases, such as obesity and type 2 diabetes. Thereby, our findings highlight the metabolic relevance of chronobiological sleep timing.

A single night of moderate at-home sleep restriction increases hunger and food intake in overweight young adults

OBJECTIVES

Experimental studies under laboratory conditions have shown a close link between acute sleep restriction and metabolic disorders. The aim of this study was to assess the effect of a single night of moderate sleep restriction implemented under ambulatory settings on sleep organization, food intake, blood pressure, and heart rate in overweight young adults.

METHODS

In a non-randomized experimental study, we evaluated 15 young, overweight adults (mean age [± SEM] 20.8 ± 0.6 y) with a mean body mass index (BMI) 27.5 ± 6.2 kg/m2 (BMI range 18.9-36.6 kg/m2). Each participant was recorded at home during two successive nights under: 1) Regular sleep routine (from 2330 to 0730 h, 'night1') and 2) Restricted sleep (6 h in bed, from 0300 to 0900 h, "night2"). Sleep was assessed by a non-invasive mobile system (Watch-PAT200) placed on the non-dominant wrist, measuring peripheral arterial tonometry. We measured sleep duration, rapid eye movement sleep (REM), light sleep (LS), deep sleep (DS), and waking. Starting 2 d before night1, four consecutive food records assessed daily food intake. Preceding and succeeding each night, hunger/satiety feelings (measured by self-reported visual analog scales), blood pressure, and heart rate were also evaluated.

RESULTS

Total sleep time was reduced in night2 (P = 0.007), with higher DS percentage (P = 0.03). Sleep onset and REM sleep latencies, LS time, and the number of wake episodes did not differ between nights. Energy intake was increased the day after night2 (P = 0.007), with increased fat and protein intakes (both P < 0.01) and feelings of hunger (P = 0.002). Systolic blood pressure was higher and heart rate faster in the morning after night2 (both P < 0.05).

CONCLUSIONS

An acute moderate at-home sleep restriction exacerbated food intake and feelings of hunger, and impaired blood pressure and heart rate regulation in young, overweight adults.

When should I run-the role of exercise timing in metabolic health

The prevalence of type 2 diabetes is reaching epidemic proportions. First line therapy approaches are lifestyle interventions including exercise. Although a vast amount of studies reports on beneficial effects of exercise on metabolism in humans per se, overall data are contradictory which makes it difficult to optimize interventions. Innovative exercise strategies and its underlying mechanism are needed to elucidate in order to close this therapeutic gap. The skeletal muscle produces and secretes myokines and microRNAs in response to exercise and both are discussed as mechanisms linking exercise and metabolic adaptation. Aspects of chronophysiology such as diurnal variation in insulin sensitivity or exercise as a signal to reset dysregulated peripheral clocks are of growing interest in the context of impaired metabolism. Deep insight of how exercise timing determines metabolic adaptations is required to optimize exercise interventions. This review aims to summarize the current state of research on the interaction between timing of exercise and metabolism in humans, providing insights into proposed mechanistic concepts focusing on myokines and microRNAs. First evidence points to an impact of timing of exercise on health outcome, although data are inconclusive. Underlying mechanisms remain elusive. It is currently unknown if the timed release of mykokines depends on time of day when exercise is performed. microRNAs have been found as an important mediator of processes associated with exercise adaptation. Further research is needed to evaluate their full relevance. In conclusion, it seems to be too early to provide concrete recommendations on timing of exercise to maximize beneficial effects.

Overall Clinical Features of Type 2 Diabetes Mellitus With Respect to Gender

Introduction Since patients with type 2 diabetes are frequently misdiagnosed, provided inappropriate management, or poorly controlled, it is important to comprehend the wide range of clinical signs and symptoms associated with diabetes. Therefore, this study evaluated the overall clinical manifestations of patients with type 2 diabetes patients with respect to gender. Methods This was a multicenter, cross-sectional study that was conducted at various hospitals, using a non-probability sampling technique. The duration of the study was about six months, from January 1, 2022 to June 30, 2022. The study included 590 type 2 diabetes patients, ranging in age from 35 to 70 years. Age, gender, socioeconomic status, health status, co-morbidities, and diabetes symptoms were documented. A chi-square was applied to determine the association between overall symptoms associated with type 2 diabetes and gender. An independent t-test was applied to determine the significance level between means of demographic parameters. Results The study findings showed that out of 590 patients with diabetes, 310 (52.5%) were males and 280 (47.5%) were females. The male and female mean ages were 57.46±14.93 and 50.38±14.85 years, respectively, with a statistically significant gender difference (p<0.001). The prevalence of renal manifestation in type 2 patients with diabetes revealed a significant relationship (p<0.05) for both genders. The prevalence of ocular manifestations revealed a significant relationship with both genders (p<0.05) in terms of distortion and blurred vision. The prevalence of ocular manifestations revealed a significant relationship observed with both genders (p<0.05) in terms of shortness of breath, dyspnea severity, and severity of chest pain. Conclusion This study concluded that women with type 2 diabetes mellitus have a significantly higher frequency of muscular pain, urinary symptoms, neurological symptoms, and dermatological manifestations than men. In contrast, respiratory symptoms were significantly more pronounced in males than in females. The presence of comorbidities such as dyslipidemia significantly increased the probability of developing type 2 diabetes in both genders.

AHA Life's essential 8 and ideal cardiovascular health among young adults

Objective

This study assessed cardiovascular health (CVH) in young adults using the 2022 AHA Life's Essential 8 (LE8) score and compared it with the Life's Simple 7 (LS7) score.

Methods

Individuals aged 18 to 44 years without a history of cardiovascular disease in the National Health and Nutrition Examination Survey (NHANES) cycles were included. Data from 2007-2008 to 2017-2018 were combined to create 3 groups (2007-2010, 2011-2014, and 2015-2018) for analysis. The LE8 score and its components were computed in the overall population and stratified by sex and race/ethnicity. Trends for the LE8 score were analyzed using adjusted linear regression models.

Results

Among 12,197 young adults, representing an estimated 89.4 million individuals, from the NHANES 2007-2018, the CVH in the overall population and across all subgroups was stable (Ptrend >0.05). The blood lipid score improved across all subgroups (Ptrend:<0.05). The mean LE8 score was 69.2±0.3. Females (71.4±0.4) had better CVH compared with males (67.2±0.4). Non-Hispanic Black individuals (65.1± 0.3) had the lowest CVH compared with Non-Hispanic White individuals (69.9±0.5), Mexican American individuals (67.3±0.3), and other race individuals (71.2±0.4). Of the 46.1 million individuals categorized as intermediate CVH by the LS7 score, 8.1 million (17.6%) and 2.3 million (5.0%) were reclassified to poor and ideal CVH by the LE8 score, respectively. Of the 40.1 million individuals categorized as ideal CVH by the LS7 score, 18.9 million (47.1%) and 0.1 million (0.2%) were reclassified to poor CVH and intermediate CVH by the LE8 score, respectively.

Conclusion

Among US young adults, there has been no improvement in CVH over the last decade with notable sex and race/ethnicity-associated differences in the LE8 score. Nearly 1 in 4 young adults had ideal CVH using the LE8 score compared with 1 in 2 individuals using the LS7 score.

Effects of acute sleep loss on leptin, ghrelin, and adiponectin in adults with healthy weight and obesity: A laboratory study

OBJECTIVE

This study investigated whether blood concentrations of leptin, ghrelin, and adiponectin are affected by acute total sleep deprivation in a sex- and weight-specific manner.

METHODS

A total of 44 participants (mean age 24.9 years; 20 women; 19 with obesity) participated in a crossover design, including one night of sleep deprivation and one night of sleep in the laboratory. After each night, fasting blood was collected.

RESULTS

After sleep deprivation, fasting levels of leptin were lower (mean [SE], vs. sleep: 17.3 [2.6] vs. 18.6 [2.8] ng/mL), whereas those of ghrelin and adiponectin were higher (839.4 [77.5] vs. 741.4 [63.2] pg/mL and 7.5 [0.6] vs. 6.8 [0.6] μg/mL, respectively; all p < 0.05). The changes in leptin and adiponectin following sleep loss were more pronounced among women. Furthermore, the ghrelin increase was stronger among those with obesity after sleep loss. Finally, the sleep loss-induced increase in adiponectin was more marked among normal-weight participants.

CONCLUSIONS

Acute sleep deprivation reduces blood concentrations of the satiety hormone leptin. With increased blood concentrations of ghrelin and adiponectin, such endocrine changes may facilitate weight gain if persisting over extended periods of sleep loss. The observed sex- and weight-specific differences in leptin, ghrelin, and adiponectin call for further investigation.

Association between sleep duration and metabolic syndrome: linear and nonlinear Mendelian randomization analyses

BACKGROUND

Observational studies have found that both short and long sleep duration are associated with increased risk of metabolic syndrome (MetS). This study aimed to examine the associations of genetically determined sleep durations with MetS and its five components (i.e., central obesity, high blood pressure, dyslipidemia, hypertriglyceridemia, and hyperglycemia) among a group of elderly population.

METHODS

In 335,727 participants of White British from the UK Biobank, linear Mendelian randomization (MR) methods were first employed to examine the causal association of genetically predicted continuous sleep duration with MetS and its each component. Nonlinear MR analyses were performed to determine the nonlinearity of these associations. The causal associations of short and long sleep duration with MetS and its components were further assessed by using genetic variants that associated with short (≤ 6 h) and long sleep (≥ 9 h) durations.

RESULTS

Linear MR analyses demonstrated that genetically predicted 1-h longer sleep duration was associated with a 13% lower risk of MetS, a 30% lower risk of central obesity, and a 26% lower risk of hyperglycemia. Non-linear MR analyses provided evidence for non-linear associations of genetically predicted sleep duration with MetS and its five components (all P values < 0.008). Genetically predicted short sleep duration was moderately associated with MetS and its four components, including central obesity, dyslipidemia, hypertriglyceridemia, and hyperglycemia (all P values < 0.002), whereas genetically long sleep duration was not associated with MetS and any of its components.

CONCLUSIONS

Genetically predicted short sleep duration, but not genetically predicted long sleep duration, is a potentially causal risk factor for MetS.

Linking knowledge with attitude: a cross-sectional study of public knowledge and attitude towards sleep disturbances and dementia

OBJECTIVES

Sleep disturbances increase the risk of dementia; however, there is insufficient information regarding this. We aimed to investigate public knowledge on the relationship between sleep disturbances and dementia, as well as attitudes towards improving sleep quality and obtaining knowledge on dementia.

DESIGN AND SETTING

A cross-sectional web-based questionnaire was administered between May and October 2019.

PARTICIPANTS

All participants provided informed consent and were able to respond to the survey.

PRIMARY OUTCOMES

Factors associated with the knowledge that sleep disturbances are risk factors for dementia and proportions of individuals with this knowledge; attitudes towards improving sleep quality and obtaining knowledge about dementia.

RESULTS

Of the 3329 eligible samples, 72.57% correctly recognised that sleep disturbances increased the risk of dementia. In total, 92.97% of participants were willing to take at least one measure to improve sleep quality, and the percentages of those adopting these measures are as follows: 78.73% would lead a regular life, 67.88% would engage in strengthening exercise, 28.84% would undergo psychotherapy and 19.41% would take medication. The awareness regarding sleep disturbances increasing the risk of dementia was the only factor associated with the willingness to improve sleep quality in all four categories of measures. Almost all participants (95.25%) were willing to take at least one measure to acquire knowledge about dementia, with the following participants displaying higher willingness to obtain knowledge about dementia: female, had contact with dementia and considered sleep disturbances to increase the risk of dementia.

CONCLUSIONS

Our findings indicate an association between people's knowledge and attitudes, suggesting the importance of disseminating knowledge about sleep disturbances and dementia to achieve dementia prevention in future.

Determinants of natural adult sleep: An umbrella review

BACKGROUND

Sleep has a major impact on health, which makes it a relevant topic for research and health practitioners. Research on sleep determinants, i.e. factors that positively or negatively influence sleep, is fragmented.

OBJECTIVE

The purpose of this umbrella review is to provide an overview of the current evidence on determinants of natural adult sleep.

METHODS

A comprehensive literature search was performed on determinants of sleep. Reviews and meta-analyses on natural adult sleep were included. Six electronic databases (PubMed, WoS, Embase, CINAHL, PsycInfo and Cochrane) were used for the search, last accessed September 2021. The quality of the selected articles was assessed using the AMSTAR2 tool. Results were categorized in four main categories: biological, behavioral, environmental and personal/socio-economical determinants.

RESULTS

In total 93 reviews and meta-analyses resulted in a total of 30 identified determinants. The impact of each determinant differs per individual and per situation. Each determinant was found to affect different sleep parameters and the relationship with sleep is influenced by both generic and specific moderators.

DISCUSSION

A comprehensive overview on relevant sleep determinants provides a practical and scientifically based starting point to identify relevant intervention approaches to secure or improve individual sleep quality. The difference in aggregation level of the determinants and in measurement methods are the major limitations of this umbrella review. Extending existing generic sleep hygiene rules with an overview of all types of potential determinants will enhance the awareness of the complexity and can be used to improve the effect of sleep interventions in health promotion.

TRIAL REGISTRATION

The umbrella review was registered with PROSPERO (registration ID CRD42020149648) https://www.google.com/search?client=firefox-b-d&q=CRD42020149648.

Association of High-Density Lipoprotein Subclasses Levels with Sleep Duration and Other Lifestyles in Middle-Aged and Elderly Women: Cross-Sectional Study

Objective: We aimed at investigating the association of high-density lipoprotein subclasses (HDL2-C and HDL3-C) levels with sleep duration, in comparison to other lifestyles in middle-aged and elderly women. Materials and Methods: A total of 69 women aged older than 40 who underwent "Anti-aging Health Checkups" were enrolled in the study. The analyses were conducted for all the subjects using personal data regarding clinical characteristics and lifestyle. Sleep duration was categorized into two groups of less than or more than 6 hrs. First, an analysis was performed to assess the correlation of two major HDL subclasses with various factors. Next, a multiple regression analysis was conducted to identify the association for each HDL2-C and HDL3-C with lifestyles such as sleep duration, daily breakfast, dinner time, habitual exercise, and drinking. Moreover, we examined the associations between HDL2-C and sleep duration combined with other lifestyle factors such as dinner time, daily breakfast, habitual exercise, and drinking. Results: In comparison to lifestyles, sleep duration had a strong association with only HDL2-C after adjustment for confounders. The "less 6 hrs sleep" group in combination with the "no exercise habit" or the "routine drinking habit" significantly decreased HDL2-C levels more than the assumed reference group. Regarding breakfast, there is a significant association between the "less than 6 hrs sleep with no daily breakfast" and the "more than 6 hrs sleep with daily breakfast." Conclusion: The results of this study may suggest that sufficient sleep might be significant for maintaining appropriate HDL2-C levels in middle-aged and elderly women under the condition that lifestyle might change during the ongoing COVID-19 pandemic.

Causal associations between sleep traits and four cardiac diseases: a Mendelian randomization study

AIMS

Previous studies investigated the associations between sleep traits and cardiac diseases, but the evidence for the causal inferences was unclear. This study aimed to explore the causal relationship between sleep and cardiac diseases by virtue of Mendelian randomization (MR).

METHODS AND RESULTS

Summary-level data for exposure variables (sleep duration, chronotype, and insomnia) and outcome variables (ischaemic heart disease, atrial fibrillation, myocardial infarction, and heart failure) were derived from UK Biobank. Data from the FinnGen consortium was used as a robustness check. In MR analysis, the inverse variance weighted (IVW) method was applied to infer causality between exposure and outcome. MR-Egger regression was used to identify pleiotropy, and MR-PRESSO outlier test was used to remove the pleiotropy of the genetic instruments. Based on UK Biobank, MR analysis suggested that sleep duration was weakly associated with atrial fibrillation (OR = 0.9999, 95% CI: 0.9998-0.9999) and ischaemic heart disease (OR = 0.9997, 95% CI: 0.9995-0.9998). Insomnia was associated with ischaemic heart disease (OR = 1.0117, 95% CI: 1.0051-1.0183) and myocardial infarction (OR = 1.0049, 95% CI: 1.0019-1.0079). No associations were found between chronotype and cardiac diseases (P > 0.05). We did not find pleiotropy except for insomnia with ischaemic heart disease and myocardial infarction using MR-Egger regression, and MR-PRESSO analysis consistent with IVW. Finally, we obtained the same direction as with UK Biobank using the FinnGen data.

CONCLUSIONS

Sleep duration and insomnia might be the potential causal risk factors of cardiac diseases. As the OR was small, these associations are probably not clinically relevant. Further validation studies are needed.

Preventive Effects of a Single Bout of Exercise on Memory and Attention following One Night of Sleep Loss in Sports Students: Results of a Randomized Controlled Study

Sleep loss is a severe problem in night-shift workers. It causes fatigue and a decrease in awareness that may be counter-acted by exercise. This randomized controlled study of 22 university students investigated the effects of exercise to prevent loss of cognitive and physical performance following sleep deprivation. We compared a single bout of 20 min circuit training to control in an experimental setting of overnight sleep loss. Outcomes included memory, cognitive tasks, and physical parameters. The occurrence of false memories was considered the main outcome. Exercise did not exert significant effects on false memories (p = 0.456). We could detect a trend to significance (p < 0.01) assessing cognitive dimensions, i.e., selective and sustained attention, and visual scanning speed. This revealed strong effects of exercise on attention (p = 0.091; Cohen’s d = 0.76; ∆14%), cognitive performance, performance speed, and perceived sleepiness (p = 0.008; d = 0.60; ∆2.4 cm VAS). This study failed to show the effects of exercise on memory function. Still, the observed effects on attention and consciousness could be considered clinically relevant, as these results encourage further research to determine its practicability and meaningfulness among night-shift workers.

Sleep duration of lactating mothers and its relationship with feeding pattern, milk macronutrients and related serum factors: A combined longitudinal cohort and cross-sectional study

Objective

Insufficient sleep is common in postpartum mothers. The main objectives of this study are to explore the sleep duration among Chinese lactating mothers and preliminarily investigate the relationship between sleep duration and feeding pattern. The secondary objectives are to investigate the relationships between sleep duration and milk macronutrients and between maternal-related indicators, including melatonin (MT), growth hormone (GH), ghrelin (GHRL), glucagon-like peptide-1 (GLP-1), prolactin (PRL), and cholecystokinin (CCK).

Methods

The present study comprises a longitudinal and a cross-sectional cohort from December 2019 to December 2021. Postpartum lactating women living in Shanghai were recruited through online and offline recruitment. The subjects were included in the longitudinal cohort or cross-sectional study based on their lactation period at the time of recruitment. The longitudinal cohort included a total of 115 mothers. Human milk and feeding pattern were measured and collected at 2–4 months and 5–7 months postpartum. At four predetermined follow-up time points, data on sleep duration was collected (at the time of recruitment, 2–4 months postpartum, 5–7 months postpartum, and 12–17 months postpartum). The cross-sectional study included 35 lactating mothers (2–12 months postpartum) who reported their sleep duration and provided blood samples. Mid-infrared spectroscopy (MIRS) method was used to analyze the macronutrients of breast milk, while MT, GH, GHRL, GLP-1, PRL, and CCK in maternal blood were determined by ELISA.

Results

The maternal sleep duration before pregnancy was 8.14 ± 1.18 h/d (n = 115), 7.27 ± 1.31 h/d (n = 113) for 2–4 months postpartum, 7.02 ± 1.05 h/d (n = 105) for 5–7 months postpartum, and 7.45 ± 1.05 h/d (n = 115) for 12–17 months postpartum. The incidence of insufficient sleep (<7 h/d) before pregnancy (12.17%) was significantly less than at any follow-up time after delivery (vs. 2–4 months postpartum, χ² = 10.101, p = 0.001; vs. 5–7 months postpartum, χ² = 15.281, p < 0.0001; vs. 12–17 months postpartum, χ² = 6.426, p = 0.011). The percentage of insufficient maternal sleep was highest at 5–7 months postpartum (34.29%). No significant difference was found between the incidence of insufficient sleep at 5–7 months postpartum, 2–4 months postpartum (29.20%, χ² = 0.650, p = 0.420), and 12–17 months postpartum (25.22%, χ² = 2.168, p = 0.141). At 2–4 months postpartum, the frequency of formula feeding per day is related to reduced maternal sleep duration (Standardization coefficient β = −0.265, p = 0.005, Adjusted R² = 0.061). At 2–4 months and 5–7 months postpartum, the relationship between macronutrients in breast milk and the mother's sleep duration was insignificant (all p > 0.05). Other than the positive correlation found between maternal GHRL and sleep duration (r = 0.3661, p = 0.0305), no significant relationship was observed between sleep duration and other indexes (all p > 0.05).

Conclusions

Postpartum mothers generally sleep less, but there is no correlation between insufficient sleep and the macronutrient content of breast milk. Formula feeding may be related to the mother's sleep loss, while breastfeeding (especially direct breastfeeding) may be related to increased maternal sleep duration. The findings suggest that sleep duration is related to maternal serum GHRL. More high-quality studies are needed to clarify the mechanism of these findings and provide a solid theoretical basis and support references for breastfeeding.

Influence of Gender in Diabetes Mellitus and Its Complication

In medicine, there is growing evidence that gender differences are important and lead to variations in the pathophysiology and treatment of many diseases with traits that appear to be particularly relevant in influencing the outcomes of many morbid forms. Today, the inclusion of gender in biomedical research, to improve the scientific quality and scientific relevance of knowledge, of technology is an increasingly present element precisely due to the practical implications that derive from it. Gender differences describe the biological variability between women and men, which is, in turn, related to differences in the information contained in sex chromosomes, the specific gene expression of autosomes linked to sex, the different number and quality of sex hormones, and their different effects on systems and organs, without neglecting the fact that each of the sexes has different target organs on which these hormones act. Additionally, both genders undergo metabolic changes throughout their lives, and this is especially true for women who show more dramatic changes due to their role in reproduction. Gender differences are not only the result of our genetic makeup but are also mixed with socio-cultural habits, behaviors, and lifestyles, differences between women and men, exposure to specific environmental influences, different food and lifestyle styles or stress, or different attitude in compliance with treatments and disease prevention campaigns. Gender differences also affect behavior throughout life, and physical changes can have implications for lifestyle, social roles, and mental health. Therefore, determinism and therapeutic outcome in chronic diseases are influenced by a complex combination of biological and environmental factors, not forgetting that there are many interactions of social and biological factors in women and men. This review will address the role of gender differences in the management of various forms of diabetes and its complications considering the different biological functions of hormones, the difference in body composition, physiological differences in glucose and fat metabolism, also considering the role of the microbiota. intestinal, as well as the description of gestational diabetes linked to possible pathophysiological events typical of reproduction.