Impact of insufficient sleep on dysregulated blood glucose control under standardised meal conditions

The impact of environmental and psychological factors on sleep quality among incarcerated persons at a correctional center in Southern Ethiopia: a cross-sectional study

PURPOSE

This study aims to assess the impact of environmental and psychological factors on sleep quality among incarcerated persons at a correctional center in southern Ethiopia.

DESIGN/METHODOLOGY/APPROACH

An institutional-based cross-sectional study was conducted at Wolaita Sodo Town Correctional Center from April 01 to 30, 2023. A systematic random sampling technique was used to recruit study participants. Binary logistic regression analyses were used to show the association of independent variables and the outcome variable. In the multivariate analysis, p-values less than 0.05 were considered statistically significant.

FINDINGS

A 60.2% prevalence of poor sleep quality was found among study participants. Factors such as generalized anxiety symptoms, depressive symptoms, history of incarceration, not engaging in physical activities and lack of income-generating opportunities while in prison were significantly associated with poor sleep quality.

RESEARCH LIMITATIONS/IMPLICATIONS

The limitations of this study were that it is a cross-sectional study; therefore, causal-impact relationships cannot be determined, and the prison environment factor was assessed by a single question without a cut-off point.

PRACTICAL IMPLICATIONS

The prevalence of poor sleep quality is notably high. Screening and treatment for depression and anxiety, promoting structured physical activity, income-generating opportunities and social reintegration training are crucial to reducing and preventing poor sleep quality.

SOCIAL IMPLICATIONS

Determining the magnitude of poor sleep quality and identifying the impact of environmental and psychological factors on sleep quality is very crucial to intervene in the future.

ORIGINALITY/VALUE

This paper is novel by addressing the detailed psychological and environmental issues that affect the sleep quality of incarcerated people at correctional center.

Getting Up in the Morning and Chronotype in Relation to Polycystic Ovarian Syndrome: A Mendelian Randomization and Cross-Sectional Study

Background

Although a connection between circadian rhythm and polycystic ovarian syndrome (PCOS) has been shown in previous studies, the exact cause of this association is not well understood.

Purpose

This study aimed to use Mendelian randomization (MR) method to analyze the potential association between getting up in the morning and chronotype with PCOS, and a cross-sectional study was conducted to further validate these results.

Methods

Using summary information from large-scale genome-wide association studies (GWASs) in people of European ancestry, we conducted univariable MR (UVMR) and multivariable MR (MVMR) analyses to examine the causal effect of genetically determined getting up in the morning and chronotype on PCOS. We also investigated the association between wake-up time and sleep midpoint with the risk of PCOS and total testosterone (TT) levels in a cohort of 777 women of reproductive age.

Results

Our findings indicate a causal relationship between the genetic prediction of getting up in the morning and chronotype with a reduced incidence of PCOS. In a cross-sectional study, a sleep midpoint of > 4:00 was linked to a higher risk of PCOS and increased TT levels than a sleep midpoint of < 3:30. In women with a BMI < 24 kg/m2, earlier wake-up times and sleep midpoints were associated with a lower risk of PCOS and decreased TT levels.

Conclusion

This study indicates that a genetic predisposition to getting up in the morning and chronotype are linked to a reduced risk of PCOS. Additionally, earlier wake-up times and sleep midpoints are associated with a lower risk of PCOS and decreased TT levels.

Precision nutrition for cardiometabolic diseases

Precision nutrition is a vibrant and rapidly evolving field of scientific research and innovation with the potential to deliver health, societal and economic benefits by improving healthcare delivery and policies. Advances in deep phenotyping technologies, digital tools and artificial intelligence have made possible early proof-of-concept research that expands the understanding of within- and between-person variability in responses to diet. These studies illustrate the promise of precision nutrition to complement the traditional 'one size fits all' dietary guidelines, which, while considering broad life-stage and disease-specific nutritional requirements, often lack the granularity to account fully for individual variations in nutritional needs and dietary responses. Despite these developments, however, considerable challenges remain before precision nutrition can be implemented on a broader scale. This Review examines the current state of precision nutrition research, with a focus on its application to reducing the incidence and burden of cardiometabolic diseases. We critically examine the evidence base, explore the potential benefits and discuss the challenges and opportunities ahead.

Circadian clock controlled glycolipid metabolism and its relevance to disease management

The circadian clock is a critical regulator of physiological rhythms, orchestrating metabolic processes to adapt to daily environmental changes. This review focuses on the intricate relationship between circadian regulation and glycolipid metabolism, with implications for metabolic diseases. Central and peripheral clocks coordinate the rhythmic expression of key enzymes and transporters, ensuring glycolipid homeostasis. Disruptions to these rhythms can result in metabolic disorders characterized by altered glucose utilization, insulin sensitivity, and lipid storage. The molecular mechanisms underlying these processes include transcriptional-translational feedback loops involving clock factors that regulate glycolipid metabolism. Emerging therapeutic strategies, such as pharmacological and dietary interventions, highlight the translational potential of circadian biology. This review underscores the importance of circadian rhythm maintenance for glycolipid metabolism and its role in preventing metabolic disorders. Further elucidation of the molecular mechanisms linking circadian regulation to glycolipid metabolism could pave the way for precision medicine approaches tailored to individual circadian profiles.

Mulberry leaf extract combined with tryptophan improves sleep and post wake mood in adults with sleep complaints - A randomized cross-over study

PURPOSE

In the current study we evaluated a blend of ingredients containing mulberry leaf extract (to lower postprandial glucose of the evening meal), tryptophan (facilitator of the sleep initiation) to benefit sleep initiation and quality in adults with self-reported difficulties with sleep initiation.

METHODS

Forty-three adults aged between 25 and 50 years enrolled in a randomized, crossover, double-blind, controlled trial. Participants received standardized meals with a glycemic load of 55 ± 10% and were assigned to receive treatment comprising a combination of mulberry leaf extract (750 mg), whey protein containing 120 mg tryptophan, zinc (1.35 mg), magnesium (12.6 mg), vitamin B3 (1.93 mg) and B6 (0.135 mg) and control (4 g wheat protein hydrolysate). Each intervention phase lasted 14 days separated by a washout period of 28 days. The primary outcomes were actigraphy-measured sleep onset latency and sleep efficiency. Secondary outcomes included continuous glycemic responses, mood, and cognition.

RESULTS

A linear mixed model intention-to-treat analysis conducted on 42 participants found that the treatment reduced sleep onset latency (actigraphy: -3.82 mins, p = 0.026; self-report: -3.09 mins, p = 0.048). Treatment significantly reduced evening meal's postprandial glucose response (incremental area under the curve, mmol/L*min) at 1 hour by 21% (p < 0.001), incremental maximum concentration by 16% (p = < 0.001) and nocturnal glucose variation over the 14-day period. Participants on treatment reported improved sleep quality (Karolinska Sleepiness Scale, -0.17, p = 0.041) and feeling more relaxed (Brief Mood Introspection Scale, -0.4, p = 0.003) the next morning compared to when taking the control. Additionally, the treatment improved the vigor dimension on the Profile of Mood Scale (0.8, p = 0.038). No effects were observed on the cognitive performance. Lowering postprandial glucose significantly mediated the treatment effect of lowering sleep onset latency and lower nocturnal glucose variation was also associated with improved sleep quality and next-day positive mood.

CONCLUSION

The evening meal supplement benefited sleep initiation and quality, and also improved post wake mood in adults.

TRIAL REGISTRATION

Registration number of Clinical Trial - ClinicalTrials.gov NCT05372900.

A good night's rest: A contemporary review of sleep and cardiovascular health

Sleep is increasingly recognized as a significant contributor to the development of cardiovascular disease (CVD). Recent American Heart Association guidelines incorporate sleep duration into the "Life's Essential Eight" framework of ideal cardiovascular health. This article will review the evidence relating sleep duration, regularity, and quality with all-cause and cardiovascular mortality, cardiometabolic syndrome, and coronary artery disease in adults. Short sleep duration is strongly associated with cardiovascular mortality, cardiometabolic risk factors, and coronary artery disease. Limited studies also suggest a possible U-shaped association, with long sleep duration also associated with greater cardiovascular risk. Sleep regularity has emerged as a strong and independent risk factor for CVD-related mortality, cardiometabolic syndrome, and subclinical atherosclerosis. Less is known about the impact of sleep quality on CVD, though a number of observational studies suggest a possible association with metabolic syndrome and subclinical atherosclerosis. This review provides an update of the literature on the cardiovascular impact of sleep for the everyday clinician and highlights gaps in knowledge that warrant future research.

Predictive models of post-prandial glucose response in persons with prediabetes and early onset type 2 diabetes: A pilot study

OBJECTIVE

Post-prandial glucose response (PPGR) is a risk factor for cardiovascular disease. Meal carbohydrate content is an important predictor of PPGR, but dietary interventions to mitigate PPGR are not always successful. A personalized approach, considering behaviour and habitual pattern of glucose excursions assessed by continuous glucose monitor (CGM), may be more effective.

RESEARCH DESIGN AND METHODS

Data were collected under free-living conditions, over 2 weeks, in older adults (age 60 ± 7, BMI 33.0 ± 6.6 kg/m2), with prediabetes (n = 35) or early onset type 2 diabetes (n = 3), together with sleep and physical activity by actigraphy. We assessed the predictive value of habitual CGM glucose excursions and fasting glucose on PPGR after a research meal (hereafter MEAL-PPGR) and during an oral glucose tolerance test (hereafter OGTT-PPGR).

RESULTS

Mean amplitude of glucose excursions (MAGE) and fasting glucose were highly predictive of all measures of OGTT-PPGR (AUC, peak, delta, mean glucose and glucose at 120 min; R2 between 0.616 and 0.786). Measures of insulin sensitivity and β-cell function (Matsuda index, HOMA-B and HOMA-IR) strengthened the prediction of fasting glucose and MAGE (R2 range 0.651 to 0.832). Similarly, MAGE and premeal glucose were also strong predictors of MEAL-PPGR (R2 range 0.546 to 0.722). Meal carbohydrates strengthened the prediction of 3 h AUC (R2 increase from 0.723 to 0.761). Neither anthropometrics, age nor habitual sleep and physical activity added to the prediction models significantly.

CONCLUSION

These data support a CGM-guided personalized nutrition and medicine approach to control PPGR in older individuals with prediabetes and diet and/or metformin-treated type 2 diabetes.

Association between glycated hemoglobin A1c levels, control status, and cognitive function in type 2 diabetes: a prospective cohort study

Cognitive impairment (CI) is a common complication in patients with type 2 diabetes mellitus (T2DM), but its relationship with long-term glycemic control remains unclear. This study aimed to investigate the associations between mean hemoglobin A1c (HbA1c) levels, HbA1c control status, HbA1c fluctuations, and CI in Chinese adults aged 45 years and older with T2DM using data from the China Health and Retirement Longitudinal Study (CHARLS). A total of 797 participants with HbA1c measurements from 2011 to 2015 and cognitive function assessments in 2018 were included. Logistic regression models and restricted cubic spline (RCS) analysis were applied, adjusting for potential confounders. Higher mean HbA1c levels (≥ 9%) were significantly associated with an increased risk of CI, particularly in global cognition and episodic memory (OR 4.03 (1.45-11.20) for global cognition; OR 2.92 (1.02-8.38) for episodic memory). RCS analysis revealed a U-shaped relationship between mean HbA1c and CI, indicating that both excessively low and high HbA1c levels elevate CI risk. Uncontrolled HbA1c levels (≥ 8%) were also linked to higher CI risk compared to stable HbA1c levels. Maintaining HbA1c levels below 8% may significantly reduce CI risk in T2DM patients, highlighting the importance of personalized glycemic management.

Effects of night-to-night variations in objectively measured sleep on blood glucose in healthy university students

STUDY OBJECTIVES

We examined associations between daily variations in objectively measured sleep and blood glucose in a sample of non-diabetic young adults to complement laboratory studies on how sleep affects blood glucose levels.

METHODS

One hundred and nineteen university students underwent sleep measurement using an Oura Ring 2 and continuous glucose monitoring (CGM) for up to 14 days. In 69 individuals who consumed a standardized diet across the study, multilevel models examined associations between sleep duration, timing, efficiency, and daily CGM profiles. Separately, in 58 individuals, multilevel models were used to evaluate postprandial glycaemic responses to a test meal challenge on 7 days. Participants also underwent oral glucose tolerance testing once after a night of ad libitum sleep, and again following a night of sleep restriction by 1-2 hours relative to that individual's habitual sleep duration. Between-condition glucose and insulin excursions, HOMA-IR and Matsuda index were compared.

RESULTS

Nocturnal sleep did not significantly influence following-day CGM profiles, postprandial glucose, or nocturnal mean glucose levels (all ps > .05). Longer sleep durations were associated with lower same-night glucose variability (all ps < .001). However, the range of variation in sugar levels was small and unlikely to be of functional significance. Considering naps in the analysis did not alter the findings. Sleep restriction by an average of 1.73 hours (SD = 0.97) did not significantly impact excursions in glucose or insulin or insulin sensitivity the following morning (all ps > .05).

CONCLUSIONS

Glucose handling in young, healthy adults may be more resilient to real-life fluctuations in sleep patterns than previously thought.

CLINICAL TRIAL INFORMATION

Monitoring Sleep and Glucose Among University Students https://clinicaltrials.gov/study/NCT04880629, ID: NCT04880629.

Imprecision nutrition? Intraindividual variability of glucose responses to duplicate presented meals in adults without diabetes

BACKGROUND

Continuous glucose monitors (CGMs) are used to characterize postprandial glucose responses and provide personalized dietary advice to minimize glucose excursions. The efficacy of such advice depends on reliable glucose responses.

OBJECTIVES

To explore within-subject variability of CGM responses to duplicate presented meals in an inpatient setting.

METHODS

CGM data were collected from two inpatient feeding studies in 30 participants without diabetes, capturing 1189 responses to duplicate meals presented ∼1 wk apart from four dietary patterns. One study used two different CGMs (Abbott Freestyle Libre Pro and Dexcom G4 Platinum) whereas the other study used only Dexcom. We calculated the incremental area under the curve (iAUC) for glucose for each 2-h postmeal period and compared within-subject, within-CGM responses to duplicate presented meals using linear correlations, intra-class correlation coefficients (ICC), and Bland-Altman analyses. Individual variability of interstitial glucose responses to duplicate meals were also compared with different meals using standard deviations (SDs).

RESULTS

There were weak-to-moderate positive linear correlations between within-subject iAUCs for duplicate meals [Abbott r = 0.46, 95% confidence interval (CI): 0.38, 0.54, P < 0.0001 and Dexcom r = 0.45, 95% CI: 0.39, 0.50, P < 0.0001], with low within-participant reliability indicated by ICC (Abbott 0.28, Dexcom 0.17). Bland-Altman analyses indicated wide limits of agreement (LoA) (Abbott -29.8 to 28.4 mg/dL and Dexcom -29.4 to 32.1 mg/dL) but small bias of mean iAUCs for duplicate meals (Abbott -0.7 mg/dL and Dexcom 1.3 mg/dL). The individual variability of interstitial glucose responses to duplicate meals was similar to that of different meals evaluated each diet week for both Abbott [SDweek1 11.7 mg/dL (compared with duplicate P = 0.01), SDweek2 10.6 mg/dL (P = 0.43), and SDduplicate 10.1 mg/dL] and Dexcom [SDweek1 10.9 mg/dL (P = 0.62), SDweek2 11.0 mg/dL (P = 0.73), and SDduplicate 11.2 mg/dL].

CONCLUSIONS

Individual postprandial CGM responses to duplicate meals were highly variable in adults without diabetes. Personalized diet advice on the basis of CGM measurements requires more reliable methods involving aggregated repeated measurements. This trial was registered at clinicaltrials.gov as NCT03407053 and NCT03878108.

Diet, physical activity, and sleep in relation to postprandial glucose responses under free-living conditions: an intensive longitudinal observational study

BACKGROUND

It remains unclear what lifestyle behaviors are optimal for controlling postprandial glucose responses under real-world circumstances in persons without diabetes. We aimed to assess associations of diet, physical activity, and sleep with postprandial glucose responses in Asian adults without diabetes under free-living conditions.

METHODS

We conducted an observational study collecting intensive longitudinal data using smartphone-based ecological momentary assessments, accelerometers, and continuous glucose monitors over nine free-living days in Singaporean men and women aged 21-69 years without diabetes. The outcome was the 2-h postprandial glucose incremental area under the curve (mmol/l*min). Associations were estimated using linear mixed-effect models.

RESULTS

The analyses included 11,333 meals in 789 participants. Greater variations in glucose and lifestyle measures were observed within individuals than between individuals. Higher consumption of carbohydrate-rich and deep-fried foods and lower consumption of protein-rich foods were significantly associated with higher postprandial glucose levels (incremental area under the curve). The strongest association was observed for including refined grains (46.2 [95% CI: 40.3, 52.1]) in meals. Longer postprandial light-intensity physical activity (-24.7 [(-39.5, -9.9] per h) and moderate-to-vigorous-intensity physical activity (-58.0 [-73.8, -42.3]) were associated with substantially lower postprandial glucose levels. Longer daily light-intensity physical activity (-7.5 [-10.7, -4.2]) and sleep duration (-2.7 [-4.4, -1.0]) were also associated with lower postprandial glucose levels. Furthermore, postprandial glucose levels were the lowest in the morning and the highest in the afternoon. The results were largely consistent for males and females and for participants with and without prediabetes.

CONCLUSIONS

Consuming less refined grains and more protein-rich foods, getting more physical activity (particularly during the postprandial period), and having a longer sleep duration were associated with lower postprandial glucose levels in Asian adults without diabetes. Our findings support multi-component lifestyle modifications for postprandial glucose control and highlight the importance of the timing of eating and physical activity.

Association between sleep quality and duration during pregnancy and risk of gestational diabetes: A systematic review and meta-analysis

OBJECTIVE

Gestational diabetes mellitus (GDM) is associated with several adverse maternal and neonatal outcomes. Previous studies reported a link between altered sleep and risk of GDM. This systematic review aims to collate evidence on the association between impaired sleep quality and duration, and the risk of GDM.

METHODS

PubMed, Embase, Web of Science, and Scopus databases were searched up to January 20, 2024. Studies reporting the association between impaired sleep quality and duration and risk of GDM were included. Sleep quality was assessed by the Pittsburgh Sleep Quality Index (PSQI). Random-effects meta-analysis was performed, and the results were reported as hazard ratio (HR) with 95% confidence interval (CI).

RESULTS

19 studies were included. Meta-analysis revealed a significant increase in the risk of GDM in pregnant women with poor sleep quality (i.e. <5 PSQI) (HR: 1.50, 95% CI: 1.26 - 1.78, p < .001). Sleep duration of <7 h (HR: 1.56, 95% CI.: 1.20 - 2.01, p < .001), and >8 h (HR: 2.32, 95% CI.: 1.19 - 4.50, p = .01) were also associated with a significantly higher incidence of GDM.

CONCLUSION

Sleep quality and duration emerge as critical risk factors of GDM. Healthcare practitioners should consider targeted interventions to improve sleep hygiene as a potential measure for GDM prevention.

The association between sleep quality and accelerated epigenetic aging with metabolic syndrome in Korean adults

BACKGROUND

Healthy sleep is vital for maintaining optimal mental and physical health. Accumulating evidence suggests that sleep loss and disturbances play a significant role in the biological aging process, early onset of disease, and reduced lifespan. While numerous studies have explored the association between biological aging and its drivers, only a few studies have examined its relationship with sleep quality. In this study, we investigated the associations between sleep quality and epigenetic age acceleration using whole blood samples from a cohort of 692 Korean adults. Sleep quality of each participant was assessed using the validated Pittsburgh Sleep Quality Index (PSQI), which encompassed seven domains: subjective sleep quality, sleep latency, sleep duration, habitual sleep efficiency, sleep disturbance, use of sleep medication, and daytime dysfunction. Four epigenetic age accelerations (HorvathAgeAccel, HannumAgeAccel, PhenoAgeAccel, and GrimAgeAccel) and the pace of aging, DunedinPACE, were investigated for epigenetic aging estimates.

RESULTS

Among the 692 participants (good sleepers [n = 441, 63.7%]; poor sleepers [n = 251, 36.3%]), DunedinPACE was positively correlated with PSQI scores in poor sleepers ( γ =0.18, p < 0.01). GrimAgeAccel ( β =0.18, p = 0.02) and DunedinPACE ( β =0.01, p < 0.01) showed a statistically significant association with PSQI scores only in poor sleepers by multiple linear regression. In addition, every one-point increase in PSQI was associated with a 15% increase in the risk of metabolic syndrome (MetS) among poor sleepers (OR = 1.15, 95% CI = 1.03-1.29, p = 0.011). In MetS components, a positive correlation was observed between PSQI score and fasting glucose ( γ = 0.19, p < 0.01).

CONCLUSIONS

This study suggests that worsening sleep quality, especially in poor sleepers, is associated with accelerated epigenetic aging for GrimAgeAccel and DundinePACE with risk of metabolic syndrome. This finding could potentially serve as a promising strategy for preventing age-related diseases in the future.

Effects of a personalized nutrition program on cardiometabolic health: a randomized controlled trial

Large variability exists in people's responses to foods. However, the efficacy of personalized dietary advice for health remains understudied. We compared a personalized dietary program (PDP) versus general advice (control) on cardiometabolic health using a randomized clinical trial. The PDP used food characteristics, individual postprandial glucose and triglyceride (TG) responses to foods, microbiomes and health history, to produce personalized food scores in an 18-week app-based program. The control group received standard care dietary advice (US Department of Agriculture Guidelines for Americans, 2020-2025) using online resources, check-ins, video lessons and a leaflet. Primary outcomes were serum low-density lipoprotein cholesterol and TG concentrations at baseline and at 18 weeks. Participants (n = 347), aged 41-70 years and generally representative of the average US population, were randomized to the PDP (n = 177) or control (n = 170). Intention-to-treat analysis (n = 347) between groups showed significant reduction in TGs (mean difference = -0.13 mmol l-1; log-transformed 95% confidence interval = -0.07 to -0.01, P = 0.016). Changes in low-density lipoprotein cholesterol were not significant. There were improvements in secondary outcomes, including body weight, waist circumference, HbA1c, diet quality and microbiome (beta-diversity) (P < 0.05), particularly in highly adherent PDP participants. However, blood pressure, insulin, glucose, C-peptide, apolipoprotein A1 and B, and postprandial TGs did not differ between groups. No serious intervention-related adverse events were reported. Following a personalized diet led to some improvements in cardiometabolic health compared to standard dietary advice. ClinicalTrials.gov registration: NCT05273268 .

Association between depressive symptoms and prediabetes: NHANES 2007-2016 findings

INTRODUCTION

The association between diabetes and depressive symptoms is well recognized. However, the impact of depressive symptoms on prediabetes remains unclear. This study aims to explore the specific correlation between depressive symptoms and prediabetes.

METHODS

A total of 7467 participants from the National Health and Nutrition Examination Survey (NHANES) were included in this study, spanning five rounds of surveys conducted between 2007 and 2016. Weighted logistic regression was utilized to assess the relationship between depressive symptoms and prediabetes.

RESULTS

Compared with the normoglycemic population, individuals with prediabetes had a significantly higher probability of experiencing trouble sleeping (P = 0.020). After adjusting for non-glucose factors, there was no significant correlation between PHQ-9 and prediabetes; however, severe depressive symptoms were positively associated with abnormal fasting plasma glucose (FPG) levels (OR = 1.093 [95 % CI 1.002, 1.192]). There was a positive correlation between trouble concentrating and FPG abnormalities (OR = 1.065 [95 % CI 1.004, 1.129]).

LIMITATIONS

The cross-sectional design limits causal inference.

CONCLUSION

Individuals with depressive symptoms, especially severe cases, should be targeted for prediabetes prevention and management efforts. The diverse symptom presentations may have distinct impacts on glucose, necessitating personalized prevention and management strategies.

Effect of Cucurbita ficifolia Bouché on glutathione level and glycosylated hemoglobin percentage in a Mexican rural population with type 2 diabetes

ETHNOPHARMACOLOGICAL IMPORTANCE

Cucurbita ficifolia Bouché fruit is widely used in Mexican traditional medicine to treat type 2 diabetes (T2D) because it has been attributed with antioxidant and hypoglycemic properties in different experimental models and T2D patients. An imbalance in physiological glutathione (GSH) concentrations increases the susceptibility to developing complications associated with oxidative stress in T2D patients.

AIM OF THE STUDY

To investigate the effect of C. ficifolia on the antioxidant properties of GSH, general health measurements, and biochemical parameters in a Mexican rural population, and to evaluate the changes in socio-affective scores of patients due to improvement in T2D.

MATERIALS AND METHODS

Twenty-seven women diagnosed with T2D with poor glycemic control volunteered and were divided into two groups: C. ficifolia (0.5 g/kg of fresh pulp weight) with hypoglycemic pharmacotherapy, and another group with only hypoglycemic pharmacotherapy, for 12 weeks. We evaluated the effect of the fresh pulp of C. ficifolia on body mass index, blood pressure, glucose, glycosylated hemoglobin, cholesterol, triglycerides, and GSH. Expanding the study, we evaluated the quality of life, anxiety, and depression scores before and after the intervention.

RESULTS

Treatment with the fresh pulp of C. ficifolia for 12 weeks reduced glycosylated hemoglobin, similar to the hypoglycemic pharmacotherapy group, and significantly increased GSH concentrations. The patients' moods did not change despite increased GSH concentrations and improved T2D control.

CONCLUSIONS

The increased GSH concentrations due to the consumption of fresh pulp of C. ficifolia could help to protect against oxidative stress and extend therapeutic benefits in addition to the usual hypoglycemic drugs in patients with T2D.

Implementation Outcomes for the SLUMBER Sleep Improvement Program in Long-Term Care

OBJECTIVES

To describe the implementation of a mentored staff-delivered sleep program in nursing facilities.

DESIGN

Modified stepped-wedge unit-level intervention.

SETTING AND PARTICIPANTS

This program was implemented in 2 New York City nursing facilities, with partial implementation (due to COVID-19) in a third facility.

METHODS

Expert mentors provided staff webinars, in-person workshops, and weekly sleep pearls via text messaging. We used the integrated Promoting Action on Research Implementation in Health Services (i-PARiHS) framework as a post hoc approach to describe key elements of the SLUMBER implementation. We measured staff participation in unit-level procedures and noted their commentary during unit workshops.

RESULTS

We completed SLUMBER within 5 units across 2 facilities and held 15 leadership meetings before and during program implementation. Sessions on each unit included 3 virtual webinar presentations and 4 in-person workshops for each nursing shift, held over a period of 3 to 4 months. Staff attendance averaged >3 sessions per individual staff member. Approximately 65% of staff present on each unit participated in any given session. Text messaging was useful for engagement, educational reinforcement, and encouraging attendance. We elevated staff as experts in the care of their residents as a strategy for staff engagement and behavior change and solicited challenging cases from staff during workshops to provide strategies to address resident behavior and encourage adoption when successful.

CONCLUSIONS AND IMPLICATIONS

Engaging staff, leadership, residents, and family of nursing facilities in implementing a multicomponent sleep quality improvement program is feasible for improving nursing facilities' sleep environment. The program required gaining trust at multiple levels through presence and empathy, and reinforcement mechanisms (primarily text messages). To improve scalability, SLUMBER could evolve from an interdisciplinary investigator-based approach to internal coaches in a train-the-trainer model to effectively and sustainably implement this program to improve sleep quality for facility residents.

Association of Physical Activity with Phenotypic Age among Populations with Different Breakfast Habits

BACKGROUND

The global aging situation has reached a serious stage, and healthy lifestyles, like regular physical activity and eating breakfast, could slow the process. Phenotypic age (PhenoAge) is regarded as a novel measure of aging. Therefore, our study aimed to quantify the impact of physical activity and eating breakfast on aging via PhenoAge and phenotypic age acceleration (PhenoAgeAccel).

METHODS

A total of 3719 adults who participated in the National Health and Nutrition Examination Survey were involved in this study. Physical activity was divided into an active group and an inactive group. According to the number of reported breakfast recalls, eating breakfast was divided into the no recalls group, one recall group, and both recalls group. Sensitivity analysis was performed by stratified analysis.

RESULTS

Active physical activity was a protective factor for PhenoAge and PhenoAgeAccel. Compared to the inactive group, the β values of the active group were -8.36 (-10.09, -6.62) for PhenoAge and -1.67 (-2.21, -1.14) for PhenoAgeAccel. The stratified analysis results showed that in the groups reporting breakfast in both recalls, one recall, and no recalls, the β values of the active group were -8.84 (-10.70, -6.98), -8.17 (-12.34, -4.00), and -3.46 (-7.74, 0.82), respectively, compared to the inactive group.

CONCLUSIONS

Active physical activity was strongly correlated with lower values of PhenoAge and PhenoAgeAccel, but the association was no longer statistically significant when combined with not regularly eating breakfast.

Effects of light therapy on sleep and circadian rhythm in older type 2 diabetics living in long-term care facilities: a randomized controlled trial

Background

Light influences the secretion of melatonin in the body and regulates circadian rhythms, which play an important role in sleep and mood. The light level of rooms in long-term care facilities is usually far below the threshold required to regulate the body's circadian rhythm, and insufficient light can easily lead to sleep and mood disturbances among older residents in nursing homes. Therefore, the objective of this study was to investigate the effects of light therapy on sleep and circadian rhythm in older adults with type 2 diabetes residing in long-term care facilities.

Methods

This study was a prospective, single-blind, randomized controlled trial. Participants were randomly assigned to either the light therapy (LT) group or the control group and received the intervention for four weeks. Primary outcomes included the Pittsburgh Sleep Quality Index (PSQI) and objective sleep parameters recorded by a sleep monitoring bracelet, Morningness-Eveningness Questionnaire (MEQ). The secondary outcome included glycated serum protein (GSP). Data was collected at three time points: at baseline (T0), immediate post-treatment (T1), and 4-week follow-up (T2). A linear mixed model analysis was used to analyzed the data.

Results

We enrolled 45 long-term care residents. Compared with the control group, significant reductions in PSQI scores were observed at T1 and T2. At T2, the sleep score of objective sleep parameters was significantly higher in the LT group compared to the control group. Additionally, compared to the baseline T0, MEQ scores were significantly lower in the LT group at T1 and T2, with no significant difference in the control group. There was no significant difference between groups in glycated serum protein values at T1 and T2. However, compared to T0, glycated serum protein values decreased in the LT group while increased in the control group at T2.

Conclusion

Light therapy had a positive effect on subjective sleep quality and circadian rhythm time type in long-term care residents with type 2 diabetes, and had a possible delayed effect on objective sleep. However, no discernible alterations in blood glucose levels were detected in this study.

Melatonin as a Chronobiotic and Cytoprotector in Non-communicable Diseases: More than an Antioxidant

A circadian disruption, manifested by disturbed sleep and low-grade inflammation, is commonly seen in noncommunicable diseases (NCDs). Cardiovascular, respiratory and renal disorders, diabetes and the metabolic syndrome, cancer, and neurodegenerative diseases are among the most common NCDs prevalent in today's 24-h/7 days Society. The decline in plasma melatonin, which is a conserved phylogenetic molecule across all known aerobic creatures, is a constant feature in NCDs. The daily evening melatonin surge synchronizes both the central pacemaker located in the hypothalamic suprachiasmatic nuclei (SCN) and myriads of cellular clocks in the periphery ("chronobiotic effect"). Melatonin is the prototypical endogenous chronobiotic agent. Several meta-analyses and consensus studies support the use of melatonin to treat sleep/wake cycle disturbances associated with NCDs. Melatonin also has cytoprotective properties, acting primarily not only as an antioxidant by buffering free radicals, but also by regulating inflammation, down-regulating pro-inflammatory cytokines, suppressing low-grade inflammation, and preventing insulin resistance, among other effects. Melatonin's phylogenetic conservation is explained by its versatility of effects. In animal models of NCDs, melatonin treatment prevents a wide range of low-inflammation-linked alterations. As a result, the therapeutic efficacy of melatonin as a chronobiotic/cytoprotective drug has been proposed. Sirtuins 1 and 3 are at the heart of melatonin's chronobiotic and cytoprotective function, acting as accessory components or downstream elements of circadian oscillators and exhibiting properties such as mitochondrial protection. Allometric calculations based on animal research show that melatonin's cytoprotective benefits may require high doses in humans (in the 100 mg/day range). If melatonin is expected to improve health in NCDs, the low doses currently used in clinical trials (i.e., 2-10 mg) are unlikely to be beneficial. Multicentre double-blind studies are required to determine the potential utility of melatonin in health promotion. Moreover, melatonin dosage and levels used should be re-evaluated based on preclinical research information.

Are postprandial glucose responses sufficiently person-specific to use in personalized dietary advice? Design of the RepEAT study: a fully controlled dietary intervention to determine the variation in glucose responses

Introduction

An elevated postprandial glucose response is associated with an increased risk of cardiometabolic diseases. Existing research suggests large heterogeneity in the postprandial glucose responses to identical meals and food products between individuals, but the effect of other consumed meals during the day and the order of meals during the day on the heterogeneity in postprandial glucose responses still needs to be investigated. In addition, the robustness of the glucose responses to meals or foods is still unknown.

Objectives

The overall aim of the project is to assess whether the glucose response to a meal is sufficiently person-specific to use in personalized dietary advice. We aim to answer the question: "How replicable are glucose responses to meals within individuals and how consistent is the variation in glucose responses between individuals?"

Methods

The question will be assessed under standardized conditions of a 9-week fully controlled dietary intervention in which all meals are the same between individuals and consumed in a fixed order at a fixed time. 63 apparently healthy men and women with a BMI of 25-40 kg/m2 and aged 45-75 years were enrolled in the RepEAT study (NCT05456815), of whom 53 participants completed the study. The RepEAT study comprised a fully controlled dietary intervention of nine weeks, consisting of three repetitive periods of three weeks. Within each three-week period, a variety of meals and food products were offered during breakfast, lunch, dinner and in between meal snacks. Throughout the dietary intervention, glucose was continuously monitored using Freestyle Libre Pro IQ monitors. Physical activity was monitored using the ActiGraph and ActivPAL. To measure the association between glucose responses and an individual's phenotype, various measurements were performed before the start of the dietary intervention including an oral glucose tolerance test, a high-fat mixed meal challenge, assessment of body fat distribution including liver fat (MRI/MRS), and cardiometabolic markers.

Discussion

The repetitive and fully controlled nature of the dietary study allows detailed assessment of the replicability of the glucose responses to meals and food products within individuals. Furthermore, the consistency of the variation between individuals independent of insulin resistance will be determined.

Imprecision nutrition? Duplicate meals result in unreliable individual glycemic responses measured by continuous glucose monitors across four dietary patterns in adults without diabetes

Background

Continuous glucose monitors (CGMs) are being used to characterize postprandial glycemic responses and thereby provide personalized dietary advice to minimize glycemic excursions. However, the efficacy of such advice depends on reliable CGM responses.

Objective

To explore within-subject variability of CGM responses to duplicate meals in an inpatient setting.

Methods

CGM data were collected in two controlled feeding studies (NCT03407053 and NCT03878108) in 30 participants without diabetes capturing 1056 meal responses in duplicate ~1 week apart from four dietary patterns. One study used two different CGMs (Abbott Freestyle Libre Pro and Dexcom G4 Platinum) whereas the other study used only Dexcom. We calculated the incremental area under the curve (iAUC) for each 2-h post-meal period and compared within-subject iAUCs using the same CGM for the duplicate meals using linear correlations, intra-class correlation coefficients (ICC), Bland-Altman analyses, and compared individual variability of glycemic responses to duplicate meals versus different meals using standard deviations (SDs).

Results

There were weak to moderate positive linear correlations between within- subject iAUCs for duplicate meals (Abbott r=0.47, p<0.0001, Dexcom r=0.43, p<0.0001), with low within-participant reliability indicated by ICC (Abbott 0.31, Dexcom 0.14). Bland-Altman analyses indicated wide limits of agreement (Abbott -31.3 to 31.5 mg/dL, Dexcom -30.8 to 30.4 mg/dL) but no significant bias of mean iAUCs for duplicate meals (Abbott 0.1 mg/dL, Dexcom -0.2 mg/dL). Individual variability of glycemic responses to duplicate meals was similar to that of different meals evaluated each diet week for both Abbott (SDduplicate = 10.7 mg/dL , SDweek 1 =12.4 mg/dL, SDweek 2 =11.6 mg/dL, p=0.38) and Dexcom (SDduplicate = 11.1 mg/dL, SDweek 1 = 11.5 mg/dL, SDweek 2 =11.9 mg/dL, p=0.60).

Conclusions

Individual postprandial CGM responses to duplicate meals were unreliable in adults without diabetes. Personalized diet advice based on CGM measurements in adults without diabetes requires more reliable methods involving aggregated repeated measurements.

Self-reported sleep characteristics are linked to type 2 diabetes in middle-aged and elderly individuals: a cross-sectional study based on NHANES

OBJECTIVE

This study was aimed to evaluate the link between sleep characteristics and type 2 diabetes of middle-aged and elderly individuals.

METHODS

Twenty thousand four hundred ninety-seven individuals enrolled in National Health and Nutritional Examination Survey (NHANES) form periods of 2005-2008 were included in this study, and 3965 individuals aged 45 years and older with complete data were detected. Variables related to sleep characteristics were analyzed by univariate analysis to identify the risk factors of type 2 diabetes, the logistic regression model was used to test for the tendency across the sections of sleep duration, and the link between sleep duration and risk of type 2 diabetes was manifested as odds ratio (OR) and 95% confidence interval (CI).

RESULTS

Six hundred ninety-four individuals with type 2 diabetes were identified and enrolled in the type 2 diabetes group, while the remaining individuals (n = 3271) were enrolled in the non-type 2 diabetes group. Individuals in the type 2 diabetes group (63.9 ± 10.2) were older than those in the non-type 2 diabetes group (61.2 ± 11.5, P < 0.001). Factors of taking longer time to fall asleep (P < 0.001), sleeping less (≤ 4 h) or more (≥ 9 h) (P < 0.001), having trouble in falling asleep (P = 0.001), frequent snoring (P < 0.001), frequent sleep apnea (P < 0.001), frequent nighttime awakenings (P = 0.004), and frequent excessive daytime sleepiness (P < 0.001) were linked to the risk of type 2 diabetes.

CONCLUSION

Our study revealed that sleep characteristics were closely linked to type 2 diabetes in middle-aged and elderly individuals, and a longer sleep duration might have protective effects against type 2 diabetes, but it should be constrained within 9 h/night.

Exploring the relationship between social jetlag with gut microbial composition, diet and cardiometabolic health, in the ZOE PREDICT 1 cohort

PURPOSE

In this study, we explore the relationship between social jetlag (SJL), a parameter of circadian misalignment, and gut microbial composition, diet and cardiometabolic health in the ZOE PREDICT 1 cohort (NCT03479866).

METHODS

We assessed demographic, diet, cardiometabolic, stool metagenomics and postprandial metabolic measures (n = 1002). We used self-reported habitual sleep (n = 934) to calculate SJL (difference in mid-sleep time point of ≥ 1.5 h on week versus weekend days). We tested group differences (SJL vs no-SJL) in cardiometabolic markers and diet (ANCOVA) adjusting for sex, age, BMI, ethnicity, and socio-economic status. We performed comparisons of gut microbial composition using machine learning and association analyses on the species level genome bins present in at least 20% of the samples.

RESULTS

The SJL group (16%, n = 145) had a greater proportion of males (39% vs 25%), shorter sleepers (average sleep < 7 h; 5% vs 3%), and were younger (38.4 ± 11.3y vs 46.8 ± 11.7y) compared to the no-SJL group. SJL was associated with a higher relative abundance of 9 gut bacteria and lower abundance of 8 gut bacteria (q < 0.2 and absolute Cohen's effect size > 0.2), in part mediated by diet. SJL was associated with unfavourable diet quality (less healthful Plant-based Diet Index), higher intakes of potatoes and sugar-sweetened beverages, and lower intakes of fruits, and nuts, and slightly higher markers of inflammation (GlycA and IL-6) compared with no-SJL (P < 0.05 adjusted for covariates); rendered non-significant after multiple testing adjustments.

CONCLUSIONS

Novel associations between SJL and a more disadvantageous gut microbiome in a cohort of predominantly adequate sleepers highlight the potential implications of SJL for health.

Nighttime ambient temperature and sleep in community-dwelling older adults

This longitudinal study examines the association between bedroom nighttime temperature and sleep quality in a sample of community dwelling older adults. Using wearable sleep monitors and environmental sensors, we assessed sleep duration, efficiency, and restlessness over an extended period within participants' homes while controlling for potential confounders and covariates. Our findings demonstrated that sleep was most efficient and restful when nighttime ambient temperature ranged between 20 and 25 °C, with a clinically relevant 5-10 % drop in sleep efficiency when the temperature increased from 25 °C to 30 °C. The associations were primarily nonlinear, and substantial between-subject variations were observed. These results highlight the potential to enhance sleep quality in older adults by optimizing home thermal environments and emphasize the importance of personalized temperature adjustments based on individual needs and circumstances. Additionally, our study underscores the potential impact of climate change on sleep quality in older adults, particularly those with lower socioeconomic status, and supports increasing their adaptive capacity in the face of a changing climate.

Glycaemic variability, assessed with continuous glucose monitors, is associated with diet, lifestyle and health in people without diabetes

Background

Continuous glucose monitors (CGMs) provide high-frequency information regarding daily glucose variation and are recognised as effective for improving glycaemic control in individuals living with diabetes. Despite increased use in individuals with non-diabetic blood glucose concentrations (euglycemia), their utility as a health tool in this population remains unclear.

Objectives

To characterise variation in time in range (TIR) and glycaemic variability in large populations without diabetes or impaired glucose tolerance; describe associations between CGM-derived glycaemic metrics and metabolic and cardiometabolic health traits; identify key diet and lifestyle factors associated with TIR and glycaemic variability.

Design

Glycaemic variability (coefficient of variation) and time spent in both the ADA secondary target range (TIRADA; 3.9-7.8 mmol/L) and a more stringent range (TIR3.9-5.6; 3.9-5.6 mmol/L) were calculated during free-living in PREDICT 1, PREDICT 2, and PREDICT 3 euglycaemic community-based volunteer cohorts. Associations between CGM derived glycaemic metrics, markers of cardiometabolic health, diet (food frequency questionnaire and logged diet records), diet-habits, and lifestyle were explored.

Results

Data from N=4135 participants (Mean SD; Age: 47 12 y; Sex: 83% Female, BMI: 27 6 kg/m2). Median glycaemic variability was 14.8% (IQR 12.6-17.6%), median TIRADA was 95.8% (IQR 89.6-98.6%) and TIR3.9-5.6 was 75.0% (IQR 64.6-82.8%). Greater TIR3.9-5.6 was associated with lower HbA1c, ASCVD 10y risk and HOMA-IR (all p < 0.05). Lower glycaemic variability was associated with lower % energy derived from carbohydrate (rs: 0.17, p < 0.01), ultra-processed foods (NOVA 4, % EI; rs: 0.12, p = 0.01) and a longer overnight fasting duration (rs: -0.10, p = 0.01).

Conclusions

A stringent TIR target provides sensitivity to detect changes in HOMA-IR, ASCVD 10 y risk and HbA1c that were not detected using ADA secondary targets. Associations among TIR, glycaemic variability, dietary intake (e.g. carbohydrate and protein) and habits (e.g. nocturnal fasting duration) highlight potential strategic targets to improve glycaemic metrics derived from continuous glucose monitors.

Gut Microbiota Composition and Functionality Are Associated With REM Sleep Duration and Continuous Glucose Levels

CONTEXT

Sleep disruption is associated with worse glucose metabolic control and altered gut microbiota in animal models.

OBJECTIVE

We aimed to evaluate the possible links among rapid eye movement (REM) sleep duration, continuous glucose levels, and gut microbiota composition.

METHODS

This observational, prospective, real-life, cross-sectional case-control study included 118 (60 with obesity), middle-aged (39.1-54.8 years) healthy volunteers recruited at a tertiary hospital. Glucose variability and REM sleep duration were assessed by 10-day continuous glucose monitoring (CGM) (Dexcom G6) and wrist actigraphy (Fitbit Charge 3), respectively. The coefficient of variation (CV), interquartile range (IQR), and SD of glucose variability was assessed and the percentage of time in range (% TIR), at 126-139 mg/dL (TIR2), and 140-199 mg/dL (TIR3) were calculated. Shotgun metagenomics sequencing was applied to study gut microbiota taxonomy and functionality.

RESULTS

Increased glycemic variability (SD, CV, and IQR) was observed among subjects with obesity in parallel to increased % TIR2 and % TIR3. REM sleep duration was independently associated with % TIR3 (β = -.339; P < .001) and glucose variability (SD, β = -.350; P < .001). Microbial taxa from the Christensenellaceae family (Firmicutes phylum) were positively associated with REM sleep and negatively with CGM levels, while bacteria from Enterobacteriacea family and bacterial functions involved in iron metabolism showed opposite associations.

CONCLUSION

Decreased REM sleep duration was independently associated with a worse glucose profile. The associations of species from Christensenellaceae and Enterobacteriaceae families with REM sleep duration and continuous glucose values suggest an integrated picture of metabolic health.

Analytical Performance of the Factory-Calibrated Flash Glucose Monitoring System FreeStyle Libre2TM in Healthy Women

Continuous glucose monitoring (CGM) is used clinically and for research purposes to capture glycaemic profiles. The accuracy of CGM among healthy populations has not been widely assessed. This study assessed agreement between glucose concentrations obtained from venous plasma and from CGM (FreeStyle Libre2TM, Abbott Diabetes Care, Witney, UK) in healthy women. Glucose concentrations were assessed after fasting and every 15 min after a standardized breakfast over a 4-h lab period. Accuracy of CGM was determined by Bland-Altman plot, 15/15% sensor agreement analysis, Clarke error grid analysis (EGA) and mean absolute relative difference (MARD). In all, 429 valid CGM readings with paired venous plasma glucose (VPG) values were obtained from 29 healthy women. Mean CGM readings were 1.14 mmol/L (95% CI: 0.97 to 1.30 mmol/L, p < 0.001) higher than VPG concentrations. Ratio 95% limits of agreement were from 0.68 to 2.20, and a proportional bias (slope: 0.22) was reported. Additionally, 45% of the CGM readings were within ±0.83 mmol/L (±15 mg/dL) or ±15% of VPG, while 85.3% were within EGA Zones A + B (clinically acceptable). MARD was 27.5% (95% CI: 20.8, 34.2%), with higher MARD values in the hypoglycaemia range and when VPG concentrations were falling. The FreeStyle Libre2TM CGM system tends to overestimate glucose concentrations compared to venous plasma samples in healthy women, especially during hypoglycaemia and during glycaemic swings.

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.

Continuous glucose monitoring in a healthy population: understanding the post-prandial glycemic response in individuals without diabetes mellitus

Continuous glucose monitoring has become a common adjunct in the management of Diabetes Mellitus. However, there has been a recent trend among individuals without diabetes using these devices as a means of monitoring their health. The increased visibility of glucose data has allowed users to study the effect lifestyle has upon post-prandial glucose levels. Although post-prandial hyperglycemia is well understood in the setting of diabetes, its impact in individuals without diabetes is less well defined. This article reviews the factors which contribute to post-prandial hyperglycemia in individuals without diabetes and how the data obtained from continuous glucose monitoring can be used to improve an individual's metabolic health.

Objective sleep characteristics and continuous glucose monitoring profiles of type 2 diabetes patients in real-life settings

AIM

To investigate the association between objective sleep parameters and glycaemic variability determined by continous glucose monitoring (CGM) among patients with type 2 diabetes, given the significant role of sleep in glycaemic control.

METHODS

In this study, CGM was carried out in 28 patients with T2D (aged 62.3 ± 4.8 years, 57% women). Sleep characteristics were assessed by actigraphy within the CGM period. CGM-derived outcomes included glucose level, and percentages of time in range (TIR) and time above range (TAR) during the monitoring period. Associations between intraindividual night-to-night variations in sleep characteristics and overall CGM outcomes were analysed using linear regression. Associations between sleep characteristics during each night and time-matched CGM outcomes were analysed using linear mixed models.

RESULTS

A total of 249 person-days of CGM, coupled with 221 nights of sleep characteristics, were documented. Greater standard deviation (SD) of objective sleep duration (minutes) between measurement nights was associated with higher glucose level (coefficient 0.018 mmol/L [95% confidence interval {CI} 0.004, 0.033], P = 0.017), smaller proportion of TIR (% in observation period; coefficient -0.20% [95% CI -0.36, -0.03], P = 0.023), and greater proportion of TAR (coefficient 0.22% [95% CI 0.06, 0.39], P = 0.011). Later sleep midpoint (minutes from midnight) was associated with greater SD of glucose during the same sleep period (coefficient 0.002 minutes [95% CI 0.0001, 0.003], P = 0.037), longer nocturnal sleep duration was associated with smaller coefficient of variation of glucose level in the upcoming day (-0.015% [95% CI -0.03, -0.001], P = 0.041).

CONCLUSION

Objectively determined sleep duration and sleep midpoint, as well as their daily variability, are associated with CGM-derived glucose profiles in T2D patients.

Associations between the Dietary Inflammatory Index and Sleep Metrics in the Energy Balance Study (EBS)

(1) Background: Sleep, a physiological necessity, has strong inflammatory underpinnings. Diet is a strong moderator of systemic inflammation. This study explored the associations between the Dietary Inflammatory Index (DII®) and sleep duration, timing, and quality from the Energy Balance Study (EBS). (2) Methods: The EBS (n = 427) prospectively explored energy intake, expenditure, and body composition. Sleep was measured using BodyMedia’s SenseWear® armband. DII scores were calculated from three unannounced dietary recalls (baseline, 1-, 2-, and 3-years). The DII was analyzed continuously and categorically (very anti-, moderately anti-, neutral, and pro-inflammatory). Linear mixed-effects models estimated the DII score impact on sleep parameters. (3) Results: Compared with the very anti-inflammatory category, the pro-inflammatory category was more likely to be female (58% vs. 39%, p = 0.02) and African American (27% vs. 3%, p < 0.01). For every one-unit increase in the change in DII score (i.e., diets became more pro-inflammatory), wake-after-sleep-onset (WASO) increased (βChange = 1.00, p = 0.01), sleep efficiency decreased (βChange = −0.16, p < 0.05), and bedtime (βChange = 1.86, p = 0.04) and waketime became later (βChange = 1.90, p < 0.05). Associations between bedtime and the DII were stronger among African Americans (βChange = 6.05, p < 0.01) than European Americans (βChange = 0.52, p = 0.64). (4) Conclusions: Future studies should address worsening sleep quality from inflammatory diets, leading to negative health outcomes, and explore potential demographic differences.

Sleep, circadian biology and skeletal muscle interactions: Implications for metabolic health

There currently exists a modern epidemic of sleep loss, triggered by the changing demands of our 21st century lifestyle that embrace 'round-the-clock' remote working hours, access to energy-dense food, prolonged periods of inactivity, and on-line social activities. Disturbances to sleep patterns impart widespread and adverse effects on numerous cells, tissues, and organs. Insufficient sleep causes circadian misalignment in humans, including perturbed peripheral clocks, leading to disrupted skeletal muscle and liver metabolism, and whole-body energy homeostasis. Fragmented or insufficient sleep also perturbs the hormonal milieu, shifting it towards a catabolic state, resulting in reduced rates of skeletal muscle protein synthesis. The interaction between disrupted sleep and skeletal muscle metabolic health is complex, with the mechanisms underpinning sleep-related disturbances on this tissue often multifaceted. Strategies to promote sufficient sleep duration combined with the appropriate timing of meals and physical activity to maintain circadian rhythmicity are important to mitigate the adverse effects of inadequate sleep on whole-body and skeletal muscle metabolic health. This review summarises the complex relationship between sleep, circadian biology, and skeletal muscle, and discusses the effectiveness of several strategies to mitigate the negative effects of disturbed sleep or circadian rhythms on skeletal muscle health.

How people wake up is associated with previous night's sleep together with physical activity and food intake

How people wake up and regain alertness in the hours after sleep is related to how they are sleeping, eating, and exercising. Here, in a prospective longitudinal study of 833 twins and genetically unrelated adults, we demonstrate that how effectively an individual awakens in the hours following sleep is not associated with their genetics, but instead, four independent factors: sleep quantity/quality the night before, physical activity the day prior, a breakfast rich in carbohydrate, and a lower blood glucose response following breakfast. Furthermore, an individual's set-point of daily alertness is related to the quality of their sleep, their positive emotional state, and their age. Together, these findings reveal a set of non-genetic (i.e., not fixed) factors associated with daily alertness that are modifiable.

Menopause is associated with postprandial metabolism, metabolic health and lifestyle: The ZOE PREDICT study

BACKGROUND

The menopause transition is associated with unfavourable alterations in health. However, postprandial metabolic changes and their mediating factors are poorly understood.

METHODS

The PREDICT 1 UK cohort (n=1002; pre- n=366, peri- n=55, and post-menopausal females n=206) assessed phenotypic characteristics, anthropometric, diet and gut microbiome data, and fasting and postprandial (0-6 h) cardiometabolic blood measurements, including continuous glucose monitoring (CGM) data. Differences between menopausal groups were assessed in the cohort and in an age-matched subgroup, adjusting for age, BMI, menopausal hormone therapy (MHT) use, and smoking status.

FINDINGS

Post-menopausal females had higher fasting blood measures (glucose, HbA1c and inflammation (GlycA), 6%, 5% and 4% respectively), sugar intakes (12%) and poorer sleep (12%) compared with pre-menopausal females (p<0.05 for all). Postprandial metabolic responses for glucose_2hiauc and insulin_2hiauc were higher (42% and 4% respectively) and CGM measures (glycaemic variability and time in range) were unfavourable post- versus pre-menopause (p<0.05 for all). In age-matched subgroups (n=150), postprandial glucose responses remained higher post-menopause (peak_0-2h 4%). MHT was associated with favourable visceral fat, fasting (glucose and insulin) and postprandial (triglyceride_6hiauc) measures. Mediation analysis showed that associations between menopause and metabolic health indicators (visceral fat, GlycA_360mins and glycaemia (peak_0-2h)) were in part mediated by diet and gut bacterial species.

INTERPRETATION

Findings from this large scale, in-depth nutrition metabolic study of menopause, support the importance of monitoring risk factors for type-2 diabetes and cardiovascular disease in mid-life to older women to reduce morbidity and mortality associated with oestrogen decline.

FUNDING

Zoe Ltd.

Closed-Loop Insulin Delivery Effects on Glycemia During Sleep and Sleep Quality in Older Adults with Type 1 Diabetes: Results from the ORACL Trial

Sleep-related effects of closed-loop therapy among older adults with type 1 diabetes have not been well established. In the OldeR Adult Closed-Loop (ORACL) randomized, crossover trial of first-generation closed-loop therapy (MiniMed 670G), participants wore actigraphy and completed sleep diaries for 14-day periods at stage end. During objectively measured sleep (actigraphy) with closed-loop versus sensor-augmented pump therapy, glucose time-in-range 70-180 mg/dL (3.9-10.0 mmol/L) was greater (90.3% vs. 78.7%, respectively; difference 8.2 percentage points [95% confidence interval {CI} 1.5 to 13.0]; P = 0.008), and there were fewer sensor hypoglycemia episodes (18 vs. 43, respectively; incident rate ratio 0.40 [95% CI 0.20 to 0.55]; P = 0.007). Sleep quality recorded daily was worse with closed-loop therapy (P = 0.006); Pittsburgh Sleep Quality Index did not differ. There were 30% more system alarms during monitored sleep with closed-loop therapy (P < 0.001). First-generation closed-loop therapy has important glycemic benefits during sleep for older adults, with deterioration in some sleep quality measures. Sleep quality warrants prioritization and investigation during advancement of closed-loop technology.