Role of sleep duration in the regulation of glucose metabolism and appetite

Depressive Symptoms, Sleep Quality, and Pain Are Associated With Frailty in Nursing Home Residents During the COVID-19 Pandemic

BACKGROUND

The COVID-19 pandemic has caused severe effects on older adults. Depressive symptoms, poor sleep quality, and pain are common in older adults with frailty. However, it is unknown the relationship between these symptoms and frailty in nursing home residents and the difference of importance between pain intensity and pain impact on frailty during the COVID-19 Pandemic. Therefore, this study aims to explore the associations between depressive symptoms, poor sleep quality, pain intensity, and pain impact with frailty in older adults living in nursing homes.

METHODS

In this cross-sectional population-based study, 172 older adults living in nursing homes from Changsha in China were included. We collected data on depressive symptoms, sleep quality, pain, and frailty using the Patient Health Questionnaire, the Pittsburgh Sleep Quality, the Brief Pain Inventory-short form, and the FRAIL-NH Scale. Generalized linear regression models were used to explore the interaction association between these symptoms with frailty.

RESULTS

Most older adults were between 80 and 90 years old. Approximately 11.6% of older adults experienced one of the following symptoms: depressive symptoms, poor sleep quality, pain intensity, or pain impact. Moreover, 76.7% of older adults experienced at least two of these symptoms. The most common overlapping symptoms were depressive symptoms and poor sleep quality (14.5%). Among nursing home residents, the most common sites of pain were the lower limbs, followed by the back. There was a strong correlation between depressive symptoms, sleep quality, pain intensity, pain impact, and frailty. After adjusting for covariates, the interaction term between any two or three symptoms of depressive symptoms, poor sleep quality, pain intensity, and pain impact was found to be associated with a higher likelihood of frailty in older adults residing in nursing homes (p< .05).

CONCLUSIONS

Depressive symptoms, poor sleep quality, pain intensity, and pain impact are common among nursing home residents. Furthermore, these symptoms interacted with each other. In future studies, multidisciplinary interventions aimed at releasing these symptoms and reducing the adverse outcome of frailty are needed.

Sleep regulation and host genetics

Due to the multifactorial and complex nature of rest, we focus on phenotypes related to sleep. Sleep regulation is a multifactorial process. In this chapter, we focus on those phenotypes inherent to sleep that are highly prevalent in the population, and that can be modulated by lifestyle, such as sleep quality and duration, insomnia, restless leg syndrome and daytime sleepiness. We, therefore, leave in the background those phenotypes that constitute infrequent pathologies or for which the current level of scientific evidence does not favour the implementation of practical approaches of this type. Similarly, the regulation of sleep quality is intimately linked to the regulation of the circadian rhythm. Although this relationship is discussed in the sections that require it, the in-depth study of circadian rhythm regulation at the molecular level deserves a separate chapter, and this is how it is dealt with in this volume.

Sleep architecture of elite soccer players surrounding match days as measured by WHOOP straps

This study aimed to quantify and compare sleep architecture before and after home and away matches in elite soccer players from the English Premier League. Across two seasons, 6 male players (age 28 ± 5 y; body mass 85.1 ± 9.5 kg; height 1.86 ± 0.09 m) wore WHOOP straps to monitor sleep across 13 matches that kicked off before 17:00 h. For each, sleep was recorded the night before (MD-1), after (MD) and following the match (MD +1). Across these 3 days total sleep time (TST), sleep efficiency (SE), sleep disturbances, wake time, light sleep, deep sleep, REM sleep, sleep and wake onsets, alongside external load, were compared. TST was reduced after MD versus MD +1 (392.9 ± 76.4 vs 459.1 ± 66.7 min, p = 0.003) but no differences existed in any other sleep variables between days (p > 0.05). TST did not differ after home (386.9 ± 75.7 min) vs. away matches (401.0 ± 78.3 min) (p = 0.475), nor did other sleep variables (p > 0.05). GPS-derived external load peaked on MD (p < 0.05). In conclusion, despite reduced TST on MD, sleep architecture was unaffected after matches played before 17:00 h, suggesting sleep quality was not significantly compromised.

Prediction models for children/adolescents with obesity/overweight: A systematic review and meta-analysis

The incidence of obesity and overweight in children and adolescents is increasing worldwide and becomes a global health concern. This study aims to evaluate the accuracy of available prediction models in early identification of obesity and overweight in general children or adolescents and identify predictive factors for the models, thus provide a reference for subsequent development of risk prediction tools for obesity and overweight in children or adolescents. Related publications were obtained from several databases such as PubMed, Embase, Cochrane Library, and Web of Science from their inception to September 18th, 2022. The novel Prediction Model Risk of Bias Assessment Tool (PROBAST) was employed to assess the bias risk of the included studies. R4.2.0 and Stata15.1 softwares were used to conduct meta-analysis. This study involved 45 cross-sectional and/or prospective studies with 126 models. Meta-analyses showed that the overall pooled index of concordance (c-index) of prediction models for children/adolescents with obesity and overweight in the training set was 0.769 (95% CI 0.754-0.785) and 0.835(95% CI 0.792-0.879), respectively. Additionally, a large number of predictors were found to be related to children's lifestyles, such as sleep duration, sleep quality, and eating speed. In conclusions, prediction models can be employed to predict obesity/overweight in children and adolescents. Most predictors are controllable factors and are associated with lifestyle. Therefore, the prediction model serves as an excellent tool to formulate effective strategies for combating obesity/overweight in pediatric patients.

Nonrestorative Sleep and Type 2 Diabetes Incidence: the Aichi Workers' Cohort Study

BACKGROUND

The term "nonrestorative sleep (NRS)" refers to unrefreshed feeling at wake-up and is a domain of poor sleep quality. Previous researches have demonstrated that NRS is linked to a number of diseases and adverse health outcomes, but less is known regarding the link between NRS and diabetes, particularly in Japanese.

METHODS

We studied 3665 middle-aged male participants of the Aichi Workers' Cohort Study who were followed-up from 2002 to 2019. Cox proportional hazards models estimated hazard ratios (HRs) and 95% confidence intervals (CIs) of incident type 2 diabetes mellitus (T2DM) in relation to NRS adjusted for potential confounding variables.

RESULTS

During a median follow-up of 14.6 years, 421 type 2 diabetes cases were identified. Participants with NRS had a higher crude incidence rate of T2DM (11.2/1,000 person-years), compared to participants without NRS (9.3/1,000 person-years). In the fully adjusted model, individuals who reported having NRS had a significantly higher risk of developing T2DM (HR: 1.36, 95% CI: 1.10-1.67). The association was observed only in participants under 50 years old (HR: 1.82, 95% CI: 1.36-2.43), not in the older (50 years or older) participants (P for interaction =0.025). In contrast, stratified analyses by the presence of shift work, obesity or sleep duration showed similar associations in all the strata.

CONCLUSIONS

NRS was associated with higher risk of T2DM in middle-aged Japanese male workers independent of a variety of lifestyle factors and other sleep problems.

Reaction of the endogenous regulatory mechanisms to early weekday wakeups: a review of its popular explanations in light of model-based simulations

Introduction: Several widely held explanations of the mechanisms underlying the responses of endogenous sleep-wake-regulating processes to early weekday wakeups have been proposed. Here, they were briefly reviewed and validated against simulations based on the rhythmostatic version of a two-process model of sleep-wake regulation. Methods: Simulated sleep times on weekdays and weekends were compared with the times averaged over 1,048 samples with either earlier or later weekday risetimes. In total, 74 paired samples were collected before and during lockdown, and 93 paired samples were collected during early and later school start times. Results: The counterintuitive predictions of the simulations included the following: 1) only one night of ad lib sleep is sufficient to restore the endogenously determined sleep times after 1 day/5 days of larger/smaller reduction/extension of the sleep/wake phase of the circadian sleep-wake cycle; 2) sleep loss on weekdays is irrecoverable; 3) irrespective of the amount of such deadweight loss, sleep on weekends is not prolonged; and 4) the control of the circadian clocks over the sleep-wake cyclicity is not disrupted throughout the week. Discussion: The following popular explanations of the gaps between weekends and weekdays in sleep timing and duration were not supported by these simulations: 1) early weekday wakeups cause "social jetlag," viewed as the weekend and weekday (back and forth) shifts of the sleep phase relative to the unchanged phase of the circadian clocks, and 2) early weekday wakeups cause an accumulation of "sleep debt paid back" on weekends, or, in other terms, people can "catch-up" or "compensate" sleep on weekends.

The path between breakfast eating habit, sleep duration and physical activity on obesity status: An epidemiological study in schoolchildren

Background: Although the literature suggests that skipping breakfast, insufficient sleep, and reduced physical activity are associated with childhood obesity their co-influence and their in-between interactions on weight status have rarely been studied. Aim: To examine the co-influence of breakfast eating habits, sleep duration, and physical activity on the weight status of children 10-12 years old from several schools of Greece. Methods: A cross-sectional study was conducted on 1688 students in Greece, during 2014-2016. Children's Body Mass Index (BMI) was calculated and classified according to the International Obesity Task Force (IOTF) classification. Logistic regression models and path analysis were used. Results: Overweight/obesity prevalence was higher in boys (32.5% vs. 20.4%; p < 0.001). Average sleep duration decreased the odds of overweight/obesity [OR (95% CI): 0.86 (0.76, 0.97)] independently of the frequency of breakfast habit. Interaction between sleep duration with breakfast habit (p = 0.002) and physical activity (p < 0.001) was observed. Path analysis showed a negative association of BMI with sleep duration (standardized beta = -0.095, p < 0.001). A third-order interaction between breakfast habit, sleep duration, and physical activity revealed that daily breakfast eating along with adequate sleep and moderate/adequate physical activity levels, decreased the odds of over-weight/obesity by 55% [OR 0.45, 95% CI (0.27, 0.72)]. Conclusion: Although sleep duration is inversely associated with weight status independently of breakfast habit, the co-influence of adequate sleep duration with frequent breakfast eating and moderate/adequate physical activity seems to be a profoundly higher associated as a result of synergy against childhood obesity.

Evaluation of weekend catch-up sleep and weekday sleep duration in relation to metabolic syndrome in Korean adults

PURPOSE

This study aimed to evaluate whether or not the relationship between weekday sleep duration and prevalence of metabolic syndrome (MetS) differs according to weekend catch-up sleep (CUS) in Korean adults.

METHODS

Data from the Korea National Health and Nutrition Examination Survey 2016-2020, including that regarding weekday sleep duration, weekend CUS, MetS components, and confounding factors such as sociodemographic factors, health behaviors, and illness-related factors, were evaluated in Korean adults aged 19 to 80 years. Complex-sample logistic regression was applied after adjusting for confounding factors.

RESULTS

Among 24,313 adults, the prevalence of MetS was lowest in individuals with 6-7 h of sleep on weekdays and CUS ≥ 2 h (17.7%, reference group). The interaction between weekday sleep duration and weekend CUS for MetS was significant. Compared to the reference group, the prevalence of MetS was higher in those who slept < 7 h and had a maximum CUS of 1 h (aORs, 1.42-1.66), and in those who slept ≥ 9 h and had a maximum CUS of 2 h (aORs, 1.28-1.82). In subjects with no CUS or CUS ≥ 2 h, the prevalence of MetS was greater even in those with adequate weekday sleep duration (7- 9 h) than in the reference group (aORs, 1.37 and 1.64, respectively).

CONCLUSION

Weekend CUS may help individuals with short weekday sleep duration reduce their odds of developing MetS, but it may worsen the condition in individuals with a long weekday sleep length.

Sleep Deficiency and Cardiometabolic Disease

Epidemiologic studies have demonstrated that short sleep duration is associated with an increased risk of cardio-metabolic health outcomes including cardiovascular disease mortality, coronary heart disease, type 2 diabetes mellitus, hypertension, and metabolic syndrome. Experimental sleep restriction studies have sought to explain these findings. This review describes the main evidence of these associations and possible mechanisms explaining them. Whether sleep extension reverses these now widely acknowledged adverse health effects and the feasibility of implementing such strategies on a public health level is discussed.

Sleep Deprivation-Induced Oxidative Stress in Rat Models: A Scoping Systematic Review

Sleep deprivation is highly prevalent in the modern world, possibly reaching epidemic proportions. While multiple theories regarding the roles of sleep exist (inactivity, energy conservation, restoration, brain plasticity and antioxidant), multiple unknowns still remain regarding the proposed antioxidant roles of sleep. The existing experimental evidence is often contradicting, with studies pointing both toward and against the presence of oxidative stress after sleep deprivation. The main goals of this review were to analyze the existing experimental data regarding the relationship between sleep deprivation and oxidative stress, to attempt to further clarify multiple aspects surrounding this relationship and to identify current knowledge gaps. Systematic searches were conducted in three major online databases for experimental studies performed on rat models with oxidative stress measurements, published between 2015 and 2022. A total of 54 studies were included in the review. Most results seem to point to changes in oxidative stress parameters after sleep deprivation, further suggesting an antioxidant role of sleep. Alterations in these parameters were observed in both paradoxical and total sleep deprivation protocols and in multiple rat strains. Furthermore, the effects of sleep deprivation seem to extend beyond the central nervous system, affecting multiple other body sites in the periphery. Sleep recovery seems to be characterized by an increased variability, with the presence of both normalizations in some parameters and long-lasting changes after sleep deprivation. Surprisingly, most studies revealed the presence of a stress response following sleep deprivation. However, the origin and the impact of the stress response during sleep deprivation remain somewhat unclear. While a definitive exclusion of the influence of the sleep deprivation protocol on the stress response is not possible, the available data seem to suggest that the observed stress response may be determined by sleep deprivation itself as opposed to the experimental conditions. Due to this fact, the observed oxidative changes could be attributed directly to sleep deprivation.

Evening chronotype, insufficient weekday sleep, and weekday-weekend gap in sleep times: What is really to blame for a reduction in self-perceived health among university students?

The association of insufficient sleep with reduced self-perceived health was previously well established. Moreover, it was sometimes shown that the indicators of poorer health were significantly related to chronotype and weekday-weekend gaps in sleep timing and duration. It remains to be elucidated, however, whether chronotype and these gaps can contribute to the reduced health self-ratings independently from shortened sleep duration or, alternatively, their relationship with health can be simply explained by their association with insufficient sleep on weekdays. In an online survey, we tested whether the self-rated health of university students can be predicted by several individual characteristics of the sleep-wake cycles, such as chronotype, weekday and weekend sleep times, weekday-weekend gap in sleep times, sleepability and wakeability at different times of the day, etc. Responses to a question about general health and to items of several questionnaires for chronobiological assessment were collected from smartphones of 1582 university students (mean age ± standard deviation was 19.5 ± 1.7 y). The results of regression analyses suggested that lower odds of having good self-rated health were significantly associated with an earlier weekday risetime, a later weekday bedtime, and, consequently, a shorter weekday time in bed. After accounting for weekday sleep, self-rated health showed significant association with neither chronotype nor weekday-weekend differences in sleep duration and timing. Besides, the adverse health effects of reduced weekday sleep were independent from the significant adverse effects of several other individual sleep-wake characteristics including poorer nighttime sleepability and lower daytime wakeability. We concluded that university students perceive the negative health impacts of losing sleep by waking up early on weekdays irrespective of their night sleep quality and daytime level of alertness. Their chronotype and weekday-weekend difference in sleep times might not be among significant contributors to this perception. It is of practical importance to consider the reduction of weekday sleep losses among the interventions aimed at preventing sleep and health problems.

Impact of Sleep Duration and Chronotype on Cardiac Structure and Function: The UK Biobank Study

Sleep duration and chronotype have been associated with increased morbidity and mortality. We assessed for associations between sleep duration and chronotype on cardiac structure and function. UK Biobank participants with CMR data and without known cardiovascular disease were included. Self-reported sleep duration was categorized as short (<7 h/d), normal (7-9 h/d) and long (>9 h/d). Self-reported chronotype was categories as "definitely morning" or "definitely evening." Analysis included 3903 middle-aged adults: 929 short, 2924 normal and 50 long sleepers; with 966 definitely-morning and 355 definitely-evening chronotypes. Long sleep was independently associated with lower left ventricular (LV) mass (-4.8%, P = 0.035), left atrial maximum volume (-8.1%, P = 0.041) and right ventricular (RV) end-diastolic volume (-4.8%, P = 0.038) compared to those with normal sleep duration. Evening chronotype was independently associated with lower LV end-diastolic volume (-2.4%, P = 0.021), RV end-diastolic volume (-3.6%, P = 0.0006), RV end systolic volume (-5.1%, P = 0.0009), RV stroke volume (RVSV -2.7%, P = 0.033), right atrial maximal volume (-4.3%, P = 0.011) and emptying fraction (+1.3%, P = 0.047) compared to morning chronotype. Sex interactions existed for sleep duration and chronotype and age interaction for chronotype even after considering potential confounders. In conclusion, longer sleep duration was independently associated with smaller LV mass, left atrial volume and RV volume. Evening chronotype was independently associated with smaller LV and RV and reduced RV function compared to morning chronotype. Sex interactions exist with cardiac remodeling most evident in males with long sleep duration and evening chronotype. Recommendations for sleep chronotype and duration may need to be individualized based on sex.

The impact of laparoscopic Roux-en-Y gastric bypass on sleep quality and duration after one year of follow-up

BACKGROUND AND AIMS

Several studies have shown the association between obesity and sleep. Roux-en-Y gastric bypass (RYGB) surgery may improve sleep disturbances in patients with obesity by influencing a variety of factors. This study aims to evaluate the impact of bariatric surgery on sleep quality.

METHODS

Patients with severe obesity referred to the obesity clinic of a center from September 2019 to October 2021 were collected. The patients were divided into two groups, depending on whether they underwent RYGB surgery. Medical comorbidities and self-report questionnaires regarding sleep quality, anxiety, and depression were collected at baseline and 1-year follow-up.

RESULTS

54 patients were included, including 25 in the bariatric surgery group and 29 in the control group. However, five patients in the RYGB surgery group and four patients in the control group were lost in the follow-up. Pittsburgh Sleep Quality Index (PSQI) was decreased from a mean of 7.7 to 3.8 in the bariatric surgery group (p-value<0.001). In contrast to the control group, the number of patients with obstructive sleep apnea was significantly reduced in the bariatric surgery group.

CONCLUSIONS

We showed a significant improvement in sleep quality following RYGB surgery. Obstructive sleep apnea, obesity/overweight, and depressive symptoms significantly improved in our study. There is a lack of a better understanding of the association between these factors and sleep quality following surgery. Therefore, further studies are recommended regarding this issue.

Spectro-spatial features in distributed human intracranial activity proactively encode peripheral metabolic activity

Mounting evidence demonstrates that the central nervous system (CNS) orchestrates glucose homeostasis by sensing glucose and modulating peripheral metabolism. Glucose responsive neuronal populations have been identified in the hypothalamus and several corticolimbic regions. However, how these CNS gluco-regulatory regions modulate peripheral glucose levels is not well understood. To better understand this process, we simultaneously measured interstitial glucose concentrations and local field potentials in 3 human subjects from cortical and subcortical regions, including the hypothalamus in one subject. Correlations between high frequency activity (HFA, 70-170 Hz) and peripheral glucose levels are found across multiple brain regions, notably in the hypothalamus, with correlation magnitude modulated by sleep-wake cycles, circadian coupling, and hypothalamic connectivity. Correlations are further present between non-circadian (ultradian) HFA and glucose levels which are higher during awake periods. Spectro-spatial features of neural activity enable decoding of peripheral glucose levels both in the present and up to hours in the future. Our findings demonstrate proactive encoding of homeostatic glucose dynamics by the CNS.

The association between daytime napping and risk of type 2 diabetes is modulated by inflammation and adiposity: Evidence from 435 342 UK-Biobank participants

BACKGROUND

Existing evidence concerning the relationship between daytime napping and type 2 diabetes (T2D) is inconsistent, and whether the effects of napping differ by body fat percentage (BFP) and C-reactive protein (CRP) is unclear. We aimed to investigate the association between daytime napping frequency and T2D risk and whether such an association was modified by BFP and CRP.

METHODS

We included 435 342 participants free of diabetes from the UK Biobank. Participants were categorized as nonnappers, occasional nappers, and frequent nappers based on napping frequency, and BFP/CRP was divided into quartiles. Cox proportional hazards models were used.

RESULTS

During a median follow-up of 9.2 years, 17 592 T2D cases occurred. Higher frequency of daytime napping was significantly associated with an increased risk of T2D. Compared with nonnappers, the adjusted hazard ratios (HRs) for occasional nappers and habitual nappers were 1.28 (95% confidence interval [CI]: 1.24-1.32) and 1.49 (95% CI: 1.41-1.57), respectively. There was a significant additive and multiplicative interaction (relative excess risk due to interaction [RERI] = 0.490, 95% CI 0.307-0.673; p for multiplicative interaction <.001) between napping and BFP, whereby a higher hazard of T2D associated with more frequent napping was greatest among participants in the highest BFP quartile (HR = 4.45, 95% CI: 3.92-5.06). The results for CRP were similar (RERI = 0.266, 95% CI: 0.094-0.439; p for multiplicative interaction <.001).

CONCLUSIONS

Higher daytime napping frequency is associated with an increased T2D risk, and such relationships are modified by BFP and CRP. These findings underscore the importance of adiposity and inflammation control to mitigate diabetes risk.

Relationship Between Sleep Duration and Metabolic Health in Adolescents

Purpose: This study analyzed the gender differences in the cross-sectional relationship between sleep duration and metabolic health in Korean adolescents. Materials and Methods: Adolescents (1234 males, 1073 females) aged 12-19 years who provided their metabolic syndrome score (MetZscore) and sleep duration were included from the Korea National Health and Nutrition Examination Survey 2016-2020 data. Waist circumference (WC), blood pressure (BP), glucose, triglycerides (TGs), and high-density lipoprotein cholesterol (HDL) were combined to create a standardized MetZscore. Gender-specific linear or quadratic relationships between sleep durations (weekday or difference between weekend and weekday sleep) and MetZscore were analyzed after adjusting for age, family affluence, and self-rated health. Results: Male adolescents displayed an inverse linear relationship between weekday sleep duration and MetZscore [B, -0.037 (confidence interval, 95% CI: -0.054 to -0.019)], whereas females showed a nonsignificant relationship. In male adolescents, the standardized scores of WC, BP, and TG decreased linearly as weekday sleep duration increased. In females, weekday sleep duration had an inverse linear association with WC score and a positive quadratic association with glucose score. MetZscore declined linearly as the difference in sleep durations between weekends and weekdays increased [B, -0.078 (95% CI: -0.123 to -0.034) in males; B, -0.042 (95% CI: -0.080 to -0.005) in females]. Although the scores of WC and HDL in males and the scores of WC and glucose in females had inverse linear relationships with the difference in sleep durations, the BP score in males had a positive quadratic association. Conclusions: According to this study, metabolic health benefited from longer weekend sleep durations than weekdays in both male and female adolescents and longer weekdays sleep durations in male adolescents.

Sleep duration and food intake in people with type 2 diabetes mellitus and factors affecting confectionery intake

AIMS/INTRODUCTION

We carried out a cross-sectional study of people with type 2 diabetes mellitus to elucidate the association between sleep duration and food intake.

MATERIALS AND METHODS

Overall, 2,887 participants with type 2 diabetes mellitus (mean age 63.0 years; 61.1% men; mean glycated hemoglobin level 7.5%) were included in this study. The participants' self-reported dietary habits and sleep duration were evaluated using a brief self-administered dietary history questionnaire and Pittsburgh Sleep Quality Index, respectively. The participants were categorized into the following four groups based on sleep duration: <6, 6-6.9, 7-7.9 (reference) and ≥8 h.

RESULTS

No significant differences were observed between the groups regarding energy intake (kcal/day), absolute intake (g/day) or relative intake (% energy) of carbohydrates, total fat, proteins and fibers. However, confectionery intake was higher in the <6 h group and lower in the ≥8 h group than in the reference group after adjustment for confounding factors. In multivariate analysis, sleep durations <6 h and ≥8 h significantly correlated with increased (95% confidence interval 0.55 to 3.6; P = 0.0078) and decreased (95% confidence interval -4.0 to -0.32; P = 0.021) confectionery intake, respectively. Confectionery intake was positively correlated with female sex, glycated hemoglobin level and dyslipidemia, whereas it was negatively correlated with alcohol consumption and current smoking status.

CONCLUSIONS

Short sleep duration is associated with high confectionery intake in people with type 2 diabetes mellitus; this might disturb their glycemic control. Therefore, short sleepers with type 2 diabetes mellitus could improve their glycemic control by avoiding confectionery intake and maintaining adequate sleep duration.

Diabetes mellitus in Bardet Biedl syndrome

PURPOSE OF REVIEW

Bardet Biedl syndrome (BBS) is a rare disease characterized by obesity and hyperphagia. Despite the very high prevalence of paediatric and adult obesity in this population, the prevalence of diabetes mellitus is not well described.

RECENT FINDINGS

Studies in small and moderately large cohorts suggest a high prevalence of traditional risk factors for diabetes mellitus in people with BBS. People with BBS appear to have a high prevalence of insulin resistance and metabolic syndrome. Small cohort studies have identified high rates of sleep disordered breathing, including sleep apnoea syndrome. Recent research has characterized traditional behavioural risk factors such as sleep hygiene and physical inactivity in people with BBS. High rates of insufficient sleep and prolonged sedentary time suggest behavioural targets of interventions to treat or prevent diabetes mellitus. Hyperphagia, likely caused by defects in the hypothalamic melanocortin-4 receptor (MC4R) neuronal pathway, pose additional challenges to behavioural interventions to prevent diabetes mellitus.

SUMMARY

Understanding the prevalence of diabetes mellitus and other metabolic disorders in people with BBS and the impact of traditional risk factors on glucose regulation are important to developing effective treatments in this population.

The relationship between sleep and appetitive conditioning: A systematic review and meta-analysis

This systematic review and meta-analysis (PROSPERO registration animal/human studies: CRD42021234793/CRD42021234790) examined the relationship between sleep and appetitive conditioning. Inclusion criteria included: a) appetitive conditioning paradigm; b) measure of conditioning; c) sleep measurement and/or sleep loss; d) human and/etor non-human animal samples; and e) written in English. Searches of seven databases returned 3777 publications. The final sample consisted of 42 studies using primarily animal samples and involving food- and drug-related conditioning tasks. We found sleep loss disrupted appetitive conditioning of food rewards (p < 0.001) but potentiated appetitive conditioning of drug rewards (p < 0.001). Furthermore, sleep loss negatively impacted extinction learning irrespective of the reward type. Post-learning sleep was associated with increases in REM sleep (p = 0.02). Findings suggest sleep loss potentiates the impact of psychoactive substances in a manner likely to produce an increased risk of problematic substance use. In obese/overweight populations, sleep loss may be associated with deficits in the conditioning and extinction of reward-related behaviours. Further research should assess the relationship between sleep and appetitive conditioning in humans.

Complex Association Among Diet Styles, Sleep Patterns, and Obesity in Patients with Diabetes

BACKGROUND

Health risk factors (HRFs), including the adjustment of disturbed sleep patterns (including disorders and duration) and improvement of dietary intake, have become relatively novel and critical strategies to prevent the development of diabesity and treat diabetic complications.

OBJECTIVE

We aimed to explore 1) whether there was an association between diet styles (including healthy and unhealthy diets) and diabesity; 2) whether sleep patterns could moderate this relationship; and 3) whether there was a complex interaction association between sleep patterns, diet styles, and diabesity.

METHODS

The study was based on a national survey conducted by the China National Diabetic Chronic Complications Study Group, this study extracted data from some cities in Anhui Province and obtained basic and lifestyle information using a detailed questionnaire for analysis. The primary exposure was diet styles, and the outcomes were body mass index (BMI) and waist circumference (WC), while HbA1c and FBG and sleep patterns were moderators. Data were pooled using logistic regression and moderation analysis.

RESULTS

The overall response rate was 92.0%. This study ultimately included 1765 participants. The mean age was 57.10 ± 10.0 years. Sociographically, participants with lower educational levels were more likely to have lower levels of WC (χ ² = 2.73) and BMI (χ ² = 3.47), were female (t=6.54), were more likely to have lower educational levels (F=13.78) and were older (F=23.75), were more likely to have higher detection rates of sleep disorders and were more likely to have other HRFs (walking, SSBs, HbA1c and TG). Additionally, diet styles were also significantly associated with BMI and WC. In the moderation analysis, SES (socioeconomic status) also affected the correlation between healthy diet style, sleep disorders and WC (β=0.20), neither in BMI nor unhealthy diet style in BMI and WC; the combination effect between diet styles, sleep patterns and HbA1c was associated with WC and BMI.

CONCLUSION

Complex associations and interactions were found between diet styles, sleep patterns, HbA1c, and diabesity. Therefore, it is necessary to understand the dietary pattern and other HRFS that cause diabesity, so as to strengthen further preventive measures. These results can provide some theoretical basis for the treatment of diabesity in the public health field.

Isocaloric Diets with Different Protein-Carbohydrate Ratios: The Effect on Sleep, Melatonin Secretion and Subsequent Nutritional Response in Healthy Young Men

This study aimed to determine the short-term effect of two isocaloric diets differing in the ratio of protein−carbohydrate on melatonin levels, sleep, and subsequent dietary intake and physical activity in healthy young men. Twenty-four healthy men took part in a crossover design including two sessions of three days on isocaloric diets whether high-protein, low-carbohydrate (HPLC) or low-protein, high-carbohydrate (LPHC) followed by 24-h free living assessments. Sleep was measured by ambulatory polysomnography pre-post-intervention. Melatonin levels were assessed on the third night of each session on eight-point salivary sampling. Physical activity was monitored by accelerometry. On day 4, participants reported their 24-h ad-libitum dietary intake. LPHC resulted in better sleep quality and increased secretion of melatonin compared to HPLC. A significant difference was noted in sleep efficiency (p < 0.05) between the two sessions. This was mainly explained by a difference in sleep onset latency (p < 0.01) which was decreased during LPHC (PRE: 15.8 ± 7.8 min, POST: 11.4 ± 4.5 min, p < 0.001). Differences were also noted in sleep staging including time spent on REM (p < 0.05) and N1 (p < 0.05). More importantly, REM latency (PRE: 97.2 ± 19.9 min, POST 112.0 ± 20.7 min, p < 0.001) and cortical arousals (PRE: 7.2 ± 3.9 event/h, POST 8.5 ± 3.3 event/h) increased in response to HPLC diet but not LPHC. On day 4, 24-h ad-libitum energy intake was higher following HPLC compared to LPHC (+64 kcal, p < 0.05) and explained by increased snacking behavior (p < 0.01) especially from carbohydrates (p < 0.05). Increased carbohydrates intake was associated with increased cortical arousals.

Influence of Educational Level and Healthy Habits on the Prevalence of Diabesity in a Spanish Working Population

Background: Diabesity is a growing problem internationally. Taking into account the importance of physical activity and diet in its prevention and treatment, the objective of this study was to delve into the impact of healthy habits on diabesity. Methods: A descriptive, cross-sectional study was carried out in 386,924 Spanish adult workers. Obesity was determined according to eleven different formulas. Life habits were also valued; sociodemographic variables; and educational level; as well as analytical and clinical variables such as blood pressure and blood glucose levels. The association between the different variables was performed using the chi-square and the Student’s t-tests when the samples were independent. A multivariate analysis was performed using the multinomial logistic regression test by calculating the odds ratio and a 95% confidence interval. The Hosmer–Lemeshow goodness-of-fit test was also performed. Results: The overall prevalence of diabesity ranged between 0.3% (95% CI 0.3–0.4) when obesity was assessed according to the abdominal volume index and 8.3% (95% CI 8.2–8.4) when evaluated according to the CUN-BAE (Clínica Universitaria de Navarra Body Adiposity Estimator) formula. The prevalence of diabesity was also higher in workers with a non-heart-healthy diet and in those who did not exercise regularly. Conclusions: The most disadvantaged socioeconomic classes are those with the highest prevalence of diabesity. It is important to prioritise prevention in populations and communities with the most unfavourable social and environmental conditions to reduce the burden of diabesity.

Sleep and Athletic Performance: Impacts on Physical Performance, Mental Performance, Injury Risk and Recovery, and Mental Health: An Update

Sleep health is an important consideration for athletic performance. Athletes are at high risk of insufficient sleep duration, poor sleep quality, daytime sleepiness and fatigue, suboptimal sleep schedules, irregular sleep schedules, and sleep and circadian disorders. These issues likely have an impact on athletic performance via several domains. Sleep loss and/or poor sleep quality can impair muscular strength, speed, and other aspects of physical performance. Sleep issues can also increase risk of concussions and other injuries and impair recovery after injury. Cognitive performance is also impacted in several domains, including vigilance, learning and memory, decision making, and creativity.

Sleep Deficiency and Cardiometabolic Disease

Epidemiologic studies have demonstrated that short sleep duration is associated with an increased risk of cardio-metabolic health outcomes including cardiovascular disease mortality, coronary heart disease, type 2 diabetes mellitus, hypertension, and metabolic syndrome. Experimental sleep restriction studies have sought to explain these findings. This review describes the main evidence of these associations and possible mechanisms explaining them. Whether sleep extension reverses these now widely acknowledged adverse health effects and the feasibility of implementing such strategies on a public health level is discussed.

Sleep behaviours and associated habits and the progression of pre-diabetes to type 2 diabetes mellitus in adults: A systematic review and meta-analysis

INTRODUCTION

Certain sleep behaviours increase risk of type 2 diabetes mellitus (T2DM) in the general population, but whether they contribute to the progression from pre-diabetes to T2DM is uncertain. We conducted a systematic review to assess this.

METHODS

Structured searches were performed on bibliographic databases (MEDLINE, EMBASE and CINAHL) from inception to 26/04/2021 for longitudinal studies/trials consisting of adults⩾18 years with pre-diabetes and sleep behaviours (short or long sleep duration (SD), late chronotype, insomnia, obstructive sleep apnoea, daytime napping and/or night-shift employment) that reported on incident T2DM or glycaemic changes. The Newcastle-Ottawa Scale was used for quality assessment.

RESULTS

Six studies were included. Meta-analysis of three studies (n = 20,139) demonstrated that short SD was associated with greater risk of progression to T2DM, hazard ratio (HR) 1.59 (95% CI 1.29-1.97), I² heterogeneity score 0%, p < 0.0001, but not for long SD, HR 1.50 (0.86-2.62), I² heterogeneity 77%, p = 0.15. The systematic review showed insomnia and night-shift duty were associated with higher progression to T2DM. Studies were rated as moderate-to-high quality.

CONCLUSIONS

Progression from pre-diabetes to T2DM increases with short SD, but only limited data exists for insomnia and night-shift duty. Whether manipulating sleep could reduce progression from pre-diabetes to T2DM needs to be examined.

Fatigue, Schedules, Sleep, and Sleepiness in U.S. Commercial Pilots During COVID-19

INTRODUCTION: COVID-19 has had a significant impact on the aviation industry. While reduced flying capacity may intuitively translate to reduced fatigue risk by way of fewer flights and duty hours, the actual impact of the pandemic on pilot fatigue is unknown.METHODS: We surveyed U.S. commercial airline pilots in late 2020 (N = 669) and early 2021 (N = 156) to assess the impact of COVID-19 on schedules and fatigue during the pandemic.RESULTS: Overall, pilots reported reduced flight and duty hours compared to prepandemic. Average sleep on workdays was slightly shorter in late 2020 (6.87 ± 1.14 h) and recovered to prepandemic levels in early 2021 (6.95 ± 1.11 h). Similarly, the frequency of sleepiness on days off and in-flight increased in late 2020, with 54% of pilots reporting an increase in in-flight sleepiness, then returned to prepandemic levels in early 2021. The use of in-flight sleepiness countermeasures remained the same across assessed time points. Pilots highlighted several factors which impacted their sleep and job performance, including limited access to nutritional food during duty days and layovers, reduced access to exercise facilities during layovers, increased stress due to job insecurity and health concerns, increased distractions and workload, and changes to scheduling.DISCUSSION: Despite a reduction in flights and duty days, COVID-19 led to increased sleepiness on days off and in flight, potentially due to the negative impact of lack of access to essential needs and heightened stress on sleep. Operators need to monitor the change in these COVID-19 related risks as the industry returns to full service.Hilditch CJ, Flynn-Evans EE. Fatigue, schedules, sleep, and sleepiness in U.S. commercial pilots during COVID-19. Aerosp Med Hum Perform. 2022; 93(5):433-441.

Dietary Patterns in Association with Sleep Duration in Iranian Adults: Results from YaHS-TAMYZ and Shahadieh Cohort Studies

Background

Little observational studies have been conducted on the association between diet and sleep. We conducted a cross-sectional study to evaluate the associations of dietary patterns with sleep duration in an Iranian population.

Methods

This study was conducted on the baseline data of two population-based Iranian cohorts: the YaHS-TAMYS and Shahedieh studies. Dietary intakes were assessed in 10451 Yazdi people aged 20-75 years. Dietary habits were derived from answers to a food frequency questionnaire, and a factor analysis using principal component analysis (PCA) was used to identify dietary patterns. The reported sleep duration was categorized as short (<6 h), normal (6-8 h) or long (>8 h). Multivariable logistic regression was used to determine the relationship between dietary patterns and the odds of short and long sleep duration.

Results

Four major dietary patterns were identified: "healthy," "western," "traditional," and "high-carbohydrate, high-fat." In the Shahedieh study, participants in the top quartile of the western dietary pattern had greater odds of short (<6 h) and long (>8 h) sleep duration (OR = 1.49; 95% CI: 1.17, 1.90; P trend <0.001 and OR = 1.46; 95% CI: 1.12, 1.90; P trend = 0.014, respectively) than those in the bottom quartile. Also, participants in the highest quartile of the high-carbohydrate, high-fat pattern had higher odds of long sleep duration compared with those in the lowest quartile (OR = 1.36; 95% CI: 1.05, 1.75; P trend = 0.005). Pooling the two studies revealed that the western dietary pattern was significantly associated with short sleep duration (OR = 1.31; 95% CI: 1.08, 1.59).

Conclusions

The western dietary pattern might inversely be associated with sleep duration. Future prospective studies are recommended to confirm these results.

Decrease in Sleep Duration and Poor Sleep Quality over Time Is Associated with an Increased Risk of Incident Non-Alcoholic Fatty Liver Disease

The impact of changes in sleep duration and sleep quality over time on the risk of non-alcoholic fatty liver disease (NAFLD) is not known. We investigated whether changes in sleep duration and in sleep quality between baseline and follow-up are associated with the risk of developing incident NAFLD. The cohort study included 86,530 Korean adults without NAFLD and with a low fibrosis score at baseline. The median follow-up was 3.6 years. Sleep duration and quality were assessed using the Pittsburgh Sleep Quality Index. Hepatic steatosis (HS) and liver fibrosis were assessed using ultrasonography and the fibrosis-4 index (FIB-4). Cox proportional hazard models were used to determine hazard ratios (HRs) and 95% confidence intervals (Cis). A total of 12,127 subjects with incident HS and 559 with incident HS plus intermediate/high FIB-4 was identified. Comparing the decrease in sleep duration of >1 h, with stable sleep duration, the multivariate-adjusted HR (95% CIs) for incident HS was 1.24 (1.15–1.35). The corresponding HRs for incident HS plus intermediate/high FIB-4 was 1.58 (1.10–2.29). Comparing persistently poor sleep quality with persistently good sleep quality, the multivariate-adjusted HR for incident HS was 1.13 (95% CI, 1.05–1.20). A decrease in sleep duration or poor sleep quality over time was associated with an increased risk of incident NAFLD, underscoring an important potential role for good sleep in preventing NAFLD risk.

The relationship between sugar-sweetened beverages, sleep disorders, and diabesity

BACKGROUND

Diabetes and obesity in adults are global issues. Obesity and type 2 diabetes mellitus (T2DM) are increasingly categorized under the umbrella term "diabesity." Health risk factors (HRFs), which include altering sleep habits and reducing sugar-sweetened beverages (SSBs) consumption, have emerged as relatively novel and crucial strategies for preventing and treating diabetes.

OBJECTIVE

We aimed to explore: 1) whether SSBs could affect diabesity in China's community; 2) whether HRFs could moderate this relationship; and 3) whether a three-way interaction exists between HRFs, SSBs, and diabesity.

METHODS

On December 10, 2018, we investigated diabetes complications in four cities in Anhui Province and obtained basic and lifestyle information using a detailed questionnaire. The primary exposure was SSBs and outcomes were body mass index (BMI) and waist circumference (WC), while glycated hemoglobin (HbA1c) and sleep patterns (including duration and disorders) were considered moderators.

RESULTS

Overall, 1920 participants were enrolled, and those who did not complete the questionnaire were excluded. Finally, this study included 1765 participants, with a response rate of 92.0%. The mean age was (57.10 ± 10.0) years. Patients with lower educational levels were more likely to have a lower prevalence of WC (χ ² = 2.73) and BMI (χ ² = 3.47), and some HRFs were positively correlated with WC and BMI. Additionally, SSBs were significantly associated with BMI (β = 1.29) and WC (β = 2.97), and there was also differences based on sex, some HRFs, such as HbA1c, FBG and TG, showed higher levels in male participants, whereas TC level was higher in female participants. In the moderation analysis, sleep patterns were also associated with total cholesterol, triglyceride, and BMI. Furthermore, there were three-way interaction effects among HbA1c, sleep patterns, and SSBs on total cholesterol, triglyceride, BMI, and WC. Moreover, sensitivity analysis demonstrated that our results were robust.

CONCLUSION

SSBs positively correlated with patterns dose-dependently. Moreover, SSBs could also be associated with sleep patterns, and blood glucose levels were correlated with diabesity. A three-way interaction effect was discovered between SSBs, sleep patterns, blood glucose levels, and patterns. Therefore, understanding the diabesity caused by SSBs and other HRFs can help prevent its occurrence.

The links between sleep duration, obesity and type 2 diabetes mellitus

Global rates of obesity and type 2 diabetes mellitus (T2DM) are increasing globally concomitant with a rising prevalence of sleep deprivation and sleep disorders. Understanding the links between sleep, obesity and T2DM might offer an opportunity to develop better prevention and treatment strategies for these epidemics. Experimental studies have shown that sleep restriction is associated with changes in energy homeostasis, insulin resistance and β-cell function. Epidemiological cohort studies established short sleep duration as a risk factor for developing obesity and T2DM. In addition, small studies suggested that short sleep duration was associated with less weight loss following lifestyle interventions or bariatric surgery. In this article, we review the epidemiological evidence linking sleep duration to obesity and T2DM and plausible mechanisms. In addition, we review the impact of changes in sleep duration on obesity and T2DM.

Contrasting compositions of sitting, standing, stepping, and sleeping time: associations with glycaemic outcome by diabetes risk

BACKGROUND

Recent evidence suggests that prolonged sitting and its adverse impact on glycaemic indicators appear to be proportional to the degree of insulin resistance. To investigate this finding in a free-living context, we aimed to examine associations of device-measured 24-h time-use compositions of sitting, standing, stepping, and sleeping with fasting glucose (FPG) and 2 h post-load glucose (2hPLG) levels, and to examine separately the associations with time-use compositions among those at lower and at higher risk of developing type 2 diabetes.

METHODS

Cross-sectional analyses examined thigh-worn inclinometer data (activPAL, 7 day, 24 h/day protocol) from 648 participants (aged 36-80 years) at either lower (< 39 mmol/mol; < 5.7% HbA1c) or higher (≥39 mmol/mol; ≥5.7% HbA1c) diabetes risk from the 2011-2012 Australian Diabetes, Obesity and Lifestyle study. Multiple linear regression models were used to examine associations of differing compositions with FPG and 2hPLG, with time spent in each behaviour allowed to vary up to 60 min.

RESULTS

In general, the associations with the FPG within the time-use compositions were small, with statistically significant associations observed for sitting and sleeping (in the lower diabetes risk group) and standing (in higher diabetes risk group) only. For 2hPLG, statistically significant associations were observed for stepping only, with findings similar between lower (β = - 0.12 95%CI:-0.22, - 0.02) and higher (β = - 0.13 95%CI:-0.26, - 0.01) risk groups. Varying the composition had minimal impact on FPG; however 1 h less sitting time and equivalent increase in standing time was associated with attenuated FPG levels in higher risk only (Δ FPG% = - 1.5 95%CI: - 2.4, - 0.5). Large differences in 2hPLG were observed for both groups when varying the composition. One hour less sitting with equivalent increase in stepping was associated with attenuated 2hPLG, with estimations similar in lower (Δ 2hPLG% = - 3.8 95%CI: - 7.3, - 0.2) and higher (Δ 2hPLG% = - 5.0 95%CI: - 9.7, - 0.0) risk for diabetes.

CONCLUSIONS

In middle-aged and older adults, glycaemic control could be improved by reducing daily sitting time and replacing it with stepping. Standing could also be beneficial for those at higher risk of developing type 2 diabetes.

Relationship between self-reported sleep duration during week-/work-days and metabolic syndrome from NHANES 2013 to 2016

PURPOSE

This research aimed at determining the relationship between self-reported sleep duration during week-/work-days and metabolic syndrome (MetS) from NHANES 2013 to 2016.

METHODS

This study analyzed data from 11,181 people aged 16 or older who took part in the NHANES (National Health and Nutrition Examination Surveys) from 2013 to 2016. A standard questionnaire was used to define self-reported sleep duration, and MetS was defined on the basis of the NCEP (National Cholesterol Education Program)/ATP III revised diagnostic criteria. Logistic regression and restricted cubic splines (RCS) models were used to assess the relationship between self-reported sleep duration and MetS.

RESULTS

The overall prevalence of MetS in the study cohort was 26.1%, with 24.8% for males and 27.3% for females. After adjusting for potential confounding factors, MetS was significantly associated with self-reported short sleep duration (odds ratio = 1.16, 95% confidence interval = 1.03-1.31, P = 0.013) but not with long sleep duration (P = 0.117). RCS regression revealed that self-reported sleep duration was nonlinearly related to MetS (P for nonlinearity = 0.0026). The risk of MetS decreased with increased sleep duration for durations of less than 7 h/day, while there was no association for longer sleep durations.

CONCLUSION

These results suggest that self-reported short sleep duration is a risk factor for MetS, while long sleep duration is not.

Sleep Duration, Sleep Quality, and the Development of Nonalcoholic Fatty Liver Disease: A Cohort Study

INTRODUCTION

The longitudinal relationship between sleep duration, sleep quality, and the risk of nonalcoholic fatty liver disease (NAFLD) is unknown. We aimed to examine the association between sleep duration, sleep quality, and NAFLD development.

METHODS

Using the Pittsburgh Sleep Quality Index, sleep duration and quality were evaluated for 143,306 NAFLD-free Korean adults with a mean age of 36.6 years, who were followed for an average of 4.0 years. Hepatic steatosis (HS) was assessed using ultrasonography and liver fibrosis by the fibrosis-4 index (FIB-4) or the NAFLD fibrosis score. Flexible parametric proportional hazard models were used to determine the hazard ratios (HRs) and 95% confidence intervals.

RESULTS

There were 27,817 subjects with incident HS, of whom 1,471 had incident HS plus intermediate/high FIB-4. Multivariable-adjusted HRs (95% confidence intervals) for incident HS comparing sleep durations of ≤5, 6, 8, and ≥ 9 hours with 7 hours were 1.19 (1.14-1.23), 1.07 (1.04-1.10), 0.98 (0.94-1.02), and 0.95 (0.87-1.03), respectively. The corresponding HRs for incident HS plus intermediate/high FIB-4 were 1.30 (1.11-1.54), 1.14 (1.01-1.29), 1.11 (0.93-1.33), and 1.08 (0.71-1.63). The association between sleep duration and HS plus intermediate/high FIB-4 was inverse in individuals with good sleep quality but tended to be U-shaped in those with poor sleep quality. The results were similar if FIB-4 was replaced by the NAFLD fibrosis score.

DISCUSSION

In young adults, short sleep duration was independently associated with an increased risk of incident NAFLD with or without intermediate/high fibrosis score, suggesting a role for inadequate sleep quantity in NAFLD risk and severity.

Eucaloric Balanced Diet Improved Objective Sleep in Adolescents with Obesity

Background: A better understanding of the influence of energy balance on sleep in adolescents, particularly those with obesity, could help develop strategies to optimize sleep in these populations. The purpose of this study was to investigate sleep under ad libitum-vs-controlled diets adjusted to energy requirement (eucaloric) among adolescents with obesity and their normal weight controls. Methods: Twenty-eight male adolescents aged between 12 and 15 years, n = 14 adolescents with obesity (OB: BMI ≥ 90th centile) and n = 14 normal weight age matched controls (NW), completed an experimental protocol comprising ad libitum or eucaloric meals for three days, in random order. During the third night of each condition, they underwent in home polysomnography (PSG). Results: An interaction effect of energy intake (EI) was detected (p < 0.001). EI was higher during ad libitum compared to the eucaloric condition (p < 0.001) and in OB compared to NW (p < 0.001) in the absence of any substantial modification to macronutrient proportions. Analyses of energy intake distribution throughout the day showed a significant interaction with both a condition and group effect during lunch and dinner. Sleep improvements were noted in OB group during the eucaloric condition compared to ad libitum with reduced sleep onset latency and N1 stage. Sleep improvements were correlated to reduced EI, especially during the evening meal. Conclusion: Simply adjusting dietary intake to energy requirement and reducing the energy proportion of the evening meal could have therapeutic effects on sleep in adolescents with obesity. However, positive energy balance alone cannot justify worsened sleep among adolescents with obesity compared to normal weight counterparts.

Eating habits are associated with subjective sleep quality outcomes among university students: findings of a cross-sectional study

PURPOSE

This study investigated the relationships between eating habits and sleep quality among university students.

METHODS

In a cross-sectional study, university students completed a self-report questionnaire to assess eating habits and meal timing. We assessed subjective sleep quality using the Pittsburgh Sleep Quality Index (PSQI) questionnaire and examined the associations between eating habits and overall sleep quality and its components.

RESULTS

Four hundred ninety-eight students participated in the study. Students who used to skip breakfast, ate late-night snacks, and replaced meals with snacks were at 1.20 times, 1.24 times, and 1.25 times higher likelihood of having poor overall sleep quality, respectively. Multiple logistic regression analysis showed that skipping breakfast (r =  - 0.111, P = 0.007), late-night snacks (r =  - 0.109, P = 0.007), replacing meals with snacks (r =  - 0.126, P = 0.002), and irregular mealtimes (r =  - 0.094, P = 0.018) were the best correlates with poor sleep quality. After adjustment to demographic variables, replacing meals with snacks followed by skipping breakfast were the best independent associations with poor sleep quality by the PSQI.

CONCLUSIONS

Eating habits and meal timing were significantly associated with sleep quality. We speculate that healthy eating habits may lead to improved sleep quality and sleep components among university students.

Syndrome Metabolic Markers, Fitness and Body Fat Is Associated with Sleep Quality in Women with Severe/Morbid Obesity

Background: Sleep is an important modulator of neuroendocrine function and glucose metabolism. Poor sleep quality is related to metabolic and endocrine alterations, including decreased glucose tolerance, decreased insulin sensitivity, and increased hunger and appetite. Objective: The aim of the present study was to determine the association between sleep quality with metabolic syndrome (MetS) markers, fitness and body fat of women with severe/morbid obesity. Methods: This cross-sectional study included 26 women with severe/morbid obesity. Fasting plasma glucose (FPG), high-density lipids (HDL-c), triglycerides (TGs), and the metabolic outcomes total cholesterol (Tc) and low-density lipids (LDL-c), systolic (SBP) and diastolic blood pressure (DBP), body composition and fitness were measured. Results: Poor sleep quality showed a positive association with body fat (%) ≥ 48.2 (OR; 8.39, 95% CI; 1.13–62.14, p = 0.037), morbid obesity (OR; 8.44, 95% CI; 1.15–66.0, p = 0.036), glucose ≥ 100 mg/dL (OR; 8.44, 95% CI; 1.15–66.0, p = 0.036) and relative handgrip strength ≤ 0.66 (OR; 12.2, 95% CI; 1.79–83.09, p = 0.011). Conclusion: sleep quality is associated with health markers in women with severe/morbid obesity.

Insomnia in older adult females is highly associated with metabolic syndrome

PURPOSE

The aim of this study is to investigate the relationships between insomnia and metabolic syndrome among Taiwanese older adults.

METHODS

This cross-sectional study enrolled participants aged over 60 years from outpatient clinics between July and September 2018. Demographic characteristics of all participants and questionnaire data for sleep duration, use of hypnotic agents, baseline activities of daily living, 5 items of the geriatric depression scale, comorbidities, medications, and risk of obstructive sleep apnea were obtained. Insomnia was defined by scores of questionnaires of the Chinese version of the Athens Insomnia Scale higher or equal to 6 points. Metabolic syndrome was diagnosed according to criteria of the National Cholesterol Education Program Adult Treatment Panel III. Multivariable forward stepwise logistic regression analysis was applied to investigate independent associations between insomnia and metabolic syndrome before and after stratifying by gender.

RESULTS

Among the 336 participants (mean age 74.9 ± 8.5 years, female 49.1%), 63.1% participants had metabolic syndrome, with significantly higher prevalence among females than males (males 56.7%; females 69.7%). Participants with metabolic syndrome had higher rates of insomnia (34.0% vs. 21.8%, P = 0.018). The significant associations between insomnia and metabolic syndrome disappeared after adjusting for all covariates. However, insomnia was independently associated with metabolic syndrome in older females (adjusted OR 2.614, 95% CI 1.011-6.763, P = 0.048) after adjusting for all covariates.

CONCLUSIONS

Insomnia is significantly associated with metabolic syndrome among older female adults. These findings suggest that gender may play a role in the pathogenesis of insomnia and metabolic syndrome in older adults.

Getting on top of sleep: Research begins to unravel the molecular mechanisms that link sleep and health

There is no doubt that sleep is good for health. Yet, understanding how sleep exerts its healing effects has been a formidable challenge.

The Sleep and Recovery Practices of Athletes

BACKGROUND

Athletes maintain a balance between stress and recovery and adopt recovery modalities that manage fatigue and enhance recovery and performance. Optimal TST is subject to individual variance. However, 7-9 h sleep is recommended for adults, while elite athletes may require more quality sleep than non-athletes.

METHODS

A total of 338 (elite n = 115, 74 males and 41 females, aged 23.44 ± 4.91 years; and sub-elite n = 223, 129 males and 94 females aged 25.71 ± 6.27) athletes were recruited from a variety of team and individual sports to complete a battery of previously validated and reliable widely used questionnaires assessing sleep, recovery and nutritional practices.

RESULTS

Poor sleep was reported by both the elite and sub-elite athlete groups (i.e., global PSQI score ≥5-elite 64% [n = 74]; sub-elite 65% [n = 146]) and there was a significant difference in sport-specific recovery practices (3.22 ± 0.90 vs. 2.91 ± 0.90; p < 0.001). Relatively high levels of fatigue (2.52 ± 1.32), stress (1.7 ± 1.31) and pain (50%, n = 169) were reported in both groups. A range of supplements were used regularly by athletes in both groups; indeed, whey (elite n = 22 and sub-elite n = 48) was the most commonly used recovery supplement in both groups. Higher alcohol consumption was observed in the sub-elite athletes (12%, n = 26) and they tended to consume more units of alcohol per drinking bout.

CONCLUSION

There is a need for athletes to receive individualised support and education regarding their sleep and recovery practices.

The Association Between Poor Sleep and the Incidence of Sport and Physical Training-Related Injuries in Adult Athletic Populations: A Systematic Review

BACKGROUND

The importance of achieving an adequate amount of sleep to optimize health and athletic performance is well recognized. Yet, a systematic evidence compilation of the risk for sport-related injury in adult athletic populations due to poor sleep does not exist.

OBJECTIVE

To examine the association between poor sleep and sport and physical training-related injuries in adult athletic populations.

DATA SOURCES

Electronic databases were searched using keywords relevant to sleep quantity and quality, and musculoskeletal injury and sport-related concussion (SRC).

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Studies were included in this systematic review if they were comprised of adult athletic populations, reported measures of sleep quantity or quality, followed participants prospectively for injury, and reported an association between sleep and incidence of sport or physical training-related injury.

STUDY APPRAISAL

The methodological quality of each study was assessed using the Newcastle-Ottawa Scale for Cohort Studies.

RESULTS

From our review of 12 prospective cohort studies, we found limited evidence supporting an association between poor sleep and injury in adult athletic populations. Specifically, there is (a) insufficient evidence supporting the associations between poor sleep and increased risk of injury in specific groups of athletic adults, including professional or elite athletes, collegiate athletes, elite or collegiate dancers, and endurance sport athletes; and (b) limited evidence of an association between poor sleep and increased risk of SRC in collegiate athletes.

CONCLUSIONS

The current evidence does not support poor sleep as an independent risk factor for increased risk of sport or physical training-related injuries in adult athletic populations. Given the methodological heterogeneity and limitations across previous studies, more prospective studies are required to determine the association between sleep and injury in this population.

Association between habitual sleep duration/quality and appetite markers in individuals with obesity

STUDY OBJECTIVES

To assess if habitual sleep duration/quality was associated with appetite in individuals with obesity, and if the association was modulated by sex.

METHODS

Sleep duration/quality was measured with Pittsburgh Sleep Quality Index score in 95 healthy adults with obesity (BMI: 36.6 ± 4.2 kg/m²). Subjective feelings of appetite were assessed using visual analogue scales, and plasma concentrations of active ghrelin, total peptide YY, active glucagon-like peptide 1, cholecystokinin (CCK) and insulin were measured in fasting and every 30 min up to 2.5 h after a meal.

RESULTS

No significant associations were found between sleep duration, or overall quality, and appetite in all participants. However, a worse sleep efficiency was associated with lower postprandial CCK, a shorter habitual sleep was associated with lower postprandial desire to eat and a lower daytime dysfunction was associated with higher prospective food consumption in fasting (P<0.05, for all). In males, a shorter habitual sleep duration and a worse subjective sleep quality were associated with increased basal and postprandial active ghrelin (P<0.05, P<0.01, P<0.01 and P<0.05, respectively). Also, a shorter habitual sleep was associated with lower basal and postprandial insulin (P<0.05 for both) and a worse overall sleep quality with lower postprandial insulin (P<0.05). In females, a worse overall sleep quality was associated with lower postprandial active ghrelin (P<0.05), and short habitual sleep with higher postprandial insulin (P<0.05).

CONCLUSION

A worse habitual sleep efficiency is associated with blunted postprandial CCK secretion in individuals with obesity. The association between habitual sleep duration/quality and insulin and active ghrelin seems to be modulated by sex, but more studies are needed to confirm these findings.

Predictors of metabolic-associated fatty liver disease (MAFLD) in adults: a population-based study in Northeastern Iran

AIM

This study aimed to identify the risk factors of metabolic (dysfunction)-associated fatty liver disease (MAFLD) among adults in northeastern Iran.

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease and hepatic manifestation of metabolic syndrome that threatens global public health. Recently, MAFLD has been proposed as a new terminology updated from NAFLD and diagnosed based on modified criteria.

METHODS

A nested case-control study was performed on the participants of the first phase of the Persian Sabzevar Cohort Study (PSCS), a survey that was conducted in northeastern Iran and enrolled 4,242 participants aged 35-70 years. In total, 968 MAFLD cases and 964 controls adjusted for age and sex were recruited. Data including demographic, lifestyle, anthropometric, biochemical, sleep pattern, and dietary intake information was collected.

RESULTS

The mean (SD [standard deviation]) age of participants was 49.2 (8.8) years, and 39.9% of the participants were males. The prevalence of MAFLD was 22.8% (95% CI [confidence interval] 19.2 - 26.3%). Increased body mass index (BMI) (OR [odds ratios] 5.51, 95% CI 2.73 - 11.10), waist circumference (WC) (OR 1.85, 95% CI 1.44 - 2.38), blood concentrations of triglycerides (TG) (OR 1.10, 95% CI 1.06 - 1.15), total cholesterol (TC) (OR 1.02, 95% CI 1.003 - 1.04), and alanine aminotransferase (AST) (OR 1.10, 95% CI 1.05 - 1.16) were significantly associated with an increased risk of the MAFLD (p-value <0.05). Furthermore, the odds of MAFLD risk was 43% higher in subjects who slept ≤ 5 hrs/day than those with ≥ 7 hrs per day of sleep (OR 1.43; 95% CI 1.07 - 1.92, p-value = 0.01).

CONCLUSION

In this study, it was found that MAFLD was best predicted by BMI, WC, and serum levels of TG, total cholesterol, and AST. Sleeping ≤ 5hrs/day compared to ≥ 7hrs/day was associated with an increased risk of MAFLD.

Vitamin D and sleep duration: Is there a bidirectional relationship?

Vitamin D contributes to numerous physiological processes within the body but primarily calcium and bone homeostasis. Emerging evidence highlights a novel role for vitamin D in maintaining and regulating optimal sleep. Sleep is a known regulator of bone health, highlighting the interconnectedness between vitamin D concentrations, sleep duration and bone metabolism. It is possible that the relationship between sleep length and vitamin D is bidirectional, with vitamin D playing a role in sleep health and conversely, sleep affecting vitamin D levels. Nevertheless, limited information on the direction of the interaction is available, and much remains to be learned concerning the complex relationship between insufficient sleep duration and vitamin D deficiency. Given the potential to implement interventions to improve sleep and vitamin D supplementation, understanding this relationship further could represent a novel way to support and improve health.

Sarcopenia during COVID-19 lockdown restrictions: long-term health effects of short-term muscle loss

The COVID-19 pandemic is an extraordinary global emergency that has led to the implementation of unprecedented measures in order to stem the spread of the infection. Internationally, governments are enforcing measures such as travel bans, quarantine, isolation, and social distancing leading to an extended period of time at home. This has resulted in reductions in physical activity and changes in dietary intakes that have the potential to accelerate sarcopenia, a deterioration of muscle mass and function (more likely in older populations), as well as increases in body fat. These changes in body composition are associated with a number of chronic, lifestyle diseases including cardiovascular disease (CVD), diabetes, osteoporosis, frailty, cognitive decline, and depression. Furthermore, CVD, diabetes, and elevated body fat are associated with greater risk of COVID-19 infection and more severe symptomology, underscoring the importance of avoiding the development of such morbidities. Here we review mechanisms of sarcopenia and their relation to the current data on the effects of COVID-19 confinement on physical activity, dietary habits, sleep, and stress as well as extended bed rest due to COVID-19 hospitalization. The potential of these factors to lead to an increased likelihood of muscle loss and chronic disease will be discussed. By offering a number of home-based strategies including resistance exercise, higher protein intakes and supplementation, we can potentially guide public health authorities to avoid a lifestyle disease and rehabilitation crisis post-COVID-19. Such strategies may also serve as useful preventative measures for reducing the likelihood of sarcopenia in general and in the event of future periods of isolation.

The effects of COVID-19 quarantine on eating and sleeping behaviors

Abstract

Since the beginning of the pandemic, the population has been exposed to a substantial period of social isolation, which leads to anxiety, fear, and metabolic and immune impairments.

Purpose

Considering that sleep restriction influences eating behavior, we highlight that changes in it may occur during the COVID-19 quarantine. Alterations in feeding time can uncouple the body clocks, leading to circadian misalignment and consequently to a disruption in homeostasis and disturbances in many metabolic functions.

Method

Narrative review.

Results

Do not apply.

Conclusion

The increase of body weight is related to increased food intake in response to mental stress and more time spent at home, increased opportunity to feed, and increased visual and olfactory stimulation to eat, which represents a potential risk of overfeeding nowadays. In this article, we postulate that the unusual lifestyle imposed by the COVID-19 quarantine may induce a circadian misalignment, which is capable to induce alterations on eating and sleep behaviors.

Associations between sleep duration and insulin resistance in European children and adolescents considering the mediating role of abdominal obesity

Background

Short sleep duration has been suggested to lead to insulin resistance both directly by altering glucose metabolism and indirectly through obesity. This study aims to investigate associations between nocturnal sleep duration and insulin resistance considering abdominal obesity as a mediator.

Methods

We analysed data of 3 900 children aged 2–15 years participating in the second (2009/10) and third (2013/14) examination wave of the European IDEFICS/I.Family study (hereafter referred to as baseline and follow-up). Information on nocturnal sleep duration was collected by questionnaires and age-standardised (SLEEP z-score). The homeostasis model assessment (HOMA) was calculated from fasting insulin and fasting glucose obtained from blood samples; waist circumference (WAIST) was measured with an inelastic tape. HOMA and WAIST were used as indicators for insulin resistance and abdominal obesity, respectively, and transformed to age- and sex-specific z-scores. Cross-sectional and longitudinal associations between SLEEP z-score and HOMA z-score were investigated based on a path model considering WAIST z-score as a mediator adjusting for relevant confounders.

Results

Cross-sectionally, baseline SLEEP z-score was negatively associated with baseline WAIST z-score (unstandardised effect estimate -0.120, 95% confidence interval [-0.167; -0.073]). We observed no direct effect of baseline SLEEP z-score on baseline HOMA z-score but a negative indirect effect through baseline WAIST z-score (-0.042 [-0.058; -0.025]). Longitudinally, there was no direct effect of baseline SLEEP z-score on HOMA z-score at follow-up but a negative indirect effect through both baseline WAIST z-score and WAIST z-score at follow-up (-0.028 [-0.040; -0.016]).

Conclusions

Our results do not support the hypothesis of an association between short sleep duration and insulin resistance independent of abdominal obesity. However, longer sleep duration may exert short and long term beneficial effects on insulin resistance through its beneficial effects on abdominal obesity.

Metabolic Factors Determining the Susceptibility to Weight Gain: Current Evidence

PURPOSE OF REVIEW

There is substantial inter-individual variability in body weight change, which is not fully accounted by differences in daily energy intake and physical activity levels. The metabolic responses to short-term perturbations in energy intake can explain part of this variability by quantifying the degree of metabolic "thriftiness" that confers more susceptibility to weight gain and more resistance to weight loss. It is unclear which metabolic factors and pathways determine this human "thrifty" phenotype. This review will investigate and summarize emerging research in the field of energy metabolism and highlight important metabolic mechanisms implicated in body weight regulation in humans.

RECENT FINDINGS

Dysfunctional adipose tissue lipolysis, reduced brown adipose tissue activity, blunted fibroblast growth factor 21 secretion in response to low-protein hypercaloric diets, and impaired sympathetic nervous system activity might constitute important metabolic factors characterizing "thriftiness" and favoring weight gain in humans. The individual propensity to weight gain in the current obesogenic environment could be ascertained by measuring specific metabolic factors which might open up new pathways to prevent and treat human obesity.