The epidemiology of sleep and obesity

Sleep Health: An Opportunity for Public Health to Address Health Equity

The concept of sleep health provides a positive holistic framing of multiple sleep characteristics, including sleep duration, continuity, timing, alertness, and satisfaction. Sleep health promotion is an underrecognized public health opportunity with implications for a wide range of critical health outcomes, including cardiovascular disease, obesity, mental health, and neurodegenerative disease. Using a socioecological framework, we describe interacting domains of individual, social, and contextual influences on sleep health. To the extent that these determinants of sleep health are modifiable, sleep and public health researchers may benefit from taking a multilevel approach for addressing disparities in sleep health. For example, in addition to providing individual-level sleep behavioral recommendations, health promotion interventions need to occur at multiple contextual levels (e.g., family, schools, workplaces, media, and policy). Because sleep health, a key indicator of overall health, is unevenly distributed across the population, we consider improving sleep health a necessary step toward achieving health equity.

Abnormal body weight and food-related behavior in school-aged children as measured by the Children's Binge Eating Disorder Scale

Obesity in children is becoming a global epidemic. Health and emotional consequences can threaten life and health both during childhood and adulthood. In this study, we aimed to assess the coexistence of overweight and obesity, binge eating disorder and detrimental attitudes toward nutrition among school-age children. We also aimed to determine the usefulness of the Children's Binge Eating Disorder Scale (C-BEDS) as a screening tool. We examined a group of over 550 healthy children aged 6-12. In all, 15% were overweight, and 6% were obese. A total of 12% of the children presented an increased risk of eating disorders. The examined group of children significantly differed in the number of positive C-BEDS responses compared with the authors of the test. Test reliability as measured by the Cronbach's alpha coefficient was .008. Preliminary results indicate that the problem of excessive body weight affects every fifth child, consistent with previous reports. The C-BEDS used in this study did not permit the identification of children, neither with the risk of Binge Eating Disorder (BED) nor subthreshold BED. This may be due to the relatively low internal consistency of the questions contained in the scale.

Sleeping Time, BMI, and Body Fat in Chinese Freshmen and Their Interrelation

INTRODUCTION

In the past two decades, urbanization in many Asian countries has led to sedentary lifestyle and overnutrition, which has set the stage for the epidemic of obesity. Those who have obesity during adolescence usually have obesity into adulthood, which causes many medical and psychological issues that can result in premature death. Recent data suggest that short sleep duration may contribute to the risk of obesity, opening a new avenue for potential intervention. The aim of this study was to describe the prevalence of sleeping time, body mass index (BMI), and fat mass in Chinese freshmen and to indicate the relationship among them.

METHODS

We conducted a cross-sectional study consisting of 1,938 freshmen aged from 18 to 24 years, including 684 (35.3%) men and 1,254 (64.7%) women. BMI, sleeping time, and other potential related variables were collected by questionnaire. Obesity and overweight were defined as BMI ≥28.0 and ≥24.0, respectively. All students were divided into three groups according to the tertiles of body fat percentage (Fat%), which were measured by bioelectrical impedance analysis. Sleeping time was divided into 3 categories based on the duration, <6, 6-8, and >8 h per day.

RESULTS

Participants who slept longer had lower BMI and Fat%. Sex, diet control, and maternal obesity were all significantly associated with BMI or Fat% after adjustment. There were significant differences between sleeping time <6 and >8 h in both overweight group and Fat% tertiles independent of adjustment used. The significant difference between sleeping time 6-8 and >8 h only existed in overweight group, while irrelevant relation was observed in both models of obesity group.

CONCLUSION

Longer sleeping time was associated with a lower BMI in Chinese freshmen, even after adjustment for multiple confounders. The overweight stage is a critical period of weight management intervention by changing sleeping time. If adolescents have entered the obesity stage, the effect size of lifestyle intervention might be significantly limited.

Depo-medroxyprogesterone acetate, weight gain and amenorrhea among obese adolescent and adult women

Objective: The aim of the study was to evaluate the correlation between obesity and the use of depot medroxyprogesterone (DMPA) with regard to weight gain and changes in bleeding pattern.Methods: A retrospective chart review was conducted of women receiving 150 mg DMPA via intramuscular injection at inpatient and outpatient clinics at the University of Mississippi Medical Centre between 1 June 2012 and 31 December 2016. Body mass indices (BMI) were assessed at baseline and at the time of final injection. Data on race, medical history, age at first DMPA injection, number and timing of injections, reported side effects, indication for DMPA use and reason for discontinuation, if applicable, were collected.Results: Of the 240 women included in the study, 3.3% were underweight, 30.8% were normal weight, 23.3% were overweight, 15% were class I obese, 9.6% were class II obese and 17.9% were class III obese; 87.9% of the population were African American. Women gained 2.40 kg (95% confidence interval 1.34-3.45) while they were on DMPA (p < .01), which after adjusting for confounding variables was inversely associated with age at initial injection (β coefficient -0.13; p = .02). Amenorrhoea was the most commonly reported change in bleeding pattern.Conclusion: Women who started DMPA at an earlier age gained the most weight over time, independently of initial BMI. Similar rates of amenorrhoea were found among all BMI categories.

Midday Napping and Successful Aging in Older People Living in the Mediterranean Region: The Epidemiological Mediterranean Islands Study (MEDIS)

The aim of the present study was to investigate the association between midday napping, sleeping hours, and successful aging among 2564 older (65+ years) individuals living in the insular Mediterranean region. Anthropometric, clinical, and socio-demographic characteristics, dietary habits, and lifestyle parameters were derived through standard procedures, while successful aging was evaluated using the validated Successful Aging Index (SAI; range 0-10). Of the 2564 participants, 74% reported midday napping. The SAI score was 2.9/10 for non-midday nappers vs. 3.5/10 for midday nappers (p = 0.001). Midday nappers were more likely to be physically active (p = 0.01) and to have higher adherence to the Mediterranean diet (p = 0.02) compared to non-midday nappers. In a fully adjusted model, midday nappers had 6.7% higher SAI score compared to the rest (p < 0.001), and the effect of midday napping was more prominent among males and participants 80+ years of age. Further analysis indicated a significant U-shaped trend between sleeping hours/day and SAI score (p < 0.001), with 8-9 h total of sleep/day, midday napping included, proposed as optimal in achieving the best SAI score. Midday napping seems to be a beneficial habit that should be promoted and encouraged in older people.

Perception of Sleep Disturbances due to Bedtime Use of Blue Light-Emitting Devices and Its Impact on Habits and Sleep Quality among Young Medical Students

Introduction

The use of blue light-emitting devices (smartphones, tablets, and laptops) at bedtime has negative effects on sleep due to light stimulation and/or problematic excessive use. We aimed to evaluate, among young medical students, if the perception of sleep disturbances due to bedtime use of these devices is consistent with healthier habits and a better sleep quality.

Materials and methods

294 medical students in medicine and pharmacy from the Faculty of Medicine and Pharmacy of Rabat, Morocco, took part in this anonymous and voluntary cross-sectional study and answered an electronic questionnaire. Student and Mann–Whitney U tests were used to compare variables between 2 groups based on their perception of sleep disturbances. The level of significance was p ≤ 0.05.

Results

286 students (97.3%) used a blue light-emitting smart device at bedtime before sleep, and sleep quality was poor (Pittsburgh Sleep Quality Index, PSQI > 5) in 101 students (35.3%). The perception of sleep disturbances due to this night usage was reported by 188 of them (65.7%). In this group, 154 (81.9%) used their device with all the lights turned off in the room (p=0.02), 34 (18.1%) put devices under pillows (p=0.04), 114 (60.6%) interrupted sleep to check messages (p < 0.001), and the mean duration use of these technologies at bedtime was 2 h ± 23 min per night (p=0.02). Also, the mean sleep duration was 6.3 hours ± 1.25 (p=0.04), 119 (63.3%) presented fatigue on waking more than one time per week (p=0.04), and 76 (40.4%) presented poor sleep quality (75.2% of the students with PSQI > 5) (p=0.005).

Conclusions

Despite the perception of sleep disturbances due to bedtime use of blue light-emitting devices, unhealthy sleep habits tend to be frequent in young medical students and worrying because it is associated to significant poor sleep quality.

Obstructive Sleep Apnea: Do Positional Patients Become Nonpositional Patients With Time?

OBJECTIVES

Obstructive sleep apnea (OSA) patients with breathing abnormalities only or mainly in the supine posture are designated positional patients (PPs), whereas nonpositional patients (NPPs) have many breathing abnormalities in both lateral and supine postures. Positional therapy (PT), the avoidance of the supine posture during sleep, is the obvious treatment for PPs. The stability over time of being PP and leading factors that are involved in converting a PP to an NPP are addressed.

METHODS

We analyzed polysomnographic (PSG) recordings of 81 consecutive adult patients with OSA who were judged to be PPs at the first PSG evaluation, and their follow-up PSGs were obtained after an average period of 6.6 years.

RESULTS

The follow-up PSGs indicated that 57 PPs (70.4%) remained PPs, whereas 24 (29.6 %) converted to NPPs. Among PPs and NPPs, body mass index (P ≤ 0.05), overall Apnea-Hypopnea Index (AHI, P ≤ 0.087), and lateral AHI (P ≤ 0.046) increased and minimum SpO₂ during rapid eye movement (REM) sleep (P ≤ 0.028) decreased significantly during the follow-up. However, among patients who became NPPs, the changes in these parameters were significantly (P ≤ 0.05) more pronounced compared to the patients who remained PPs.

CONCLUSION

After an average of 6.6 years, 70.4% of PPs remained PPs. Therefore, if adherence for PT is good, they could continue to benefit from this therapy. For those who turned to NPPs, PT will not be the optimal treatment anymore; thus, these patients should be frequently monitored. Furthermore, an early treatment of PPs with PT would be highly beneficial to prevent worsening of their OSA.

LEVEL OF EVIDENCE

2b Laryngoscope, 130:2263-2268, 2020.

Causal Effect of Sleep Duration on Body Weight in Adolescents: A Population-based Study Using a Natural Experiment

Supplemental Digital Content is available in the text.

A large number of observational epidemiologic studies have reported consistent associations between short sleep duration and increased body weight, particularly in children and adolescents. Causal evidence on the effect of sleep duration on body weight is still limited, however.

Bridging the Reciprocal Gap between Sleep and Fruit and Vegetable Consumption: A Review of the Evidence, Potential Mechanisms, Implications, and Directions for Future Work

A substantial burden of disease and mortality globally is attributable to both sleep disruption and low intakes of fruit and vegetable (FV) and there is increasing mechanistic and epidemiological evidence to support a reciprocal relationship between the two. This review provides an overview of experimental and observational studies assessing the relations between sleep and FV consumption from 52 human adult studies. Experimental studies are currently limited and show inconsistent results. Observational studies support a non-linear association with adults sleeping the recommended 7–9 hours/day having the highest intakes of FV. The potential mechanisms linking sleep and FV consumption are highlighted. Disrupted sleep influences FV consumption through homeostatic and non-homeostatic mechanisms. Conversely, FV consumption may influence sleep through polyphenol content via several potential pathways. Few human experimental studies have examined the effects of FV items and their polyphenols on sleep and there is a need for more studies to address this. An appreciation of the relationship between sleep and FV consumption may help optimize sleep and FV consumption and may reduce the burden of chronic diseases. This review provides implications for public health and directions for future work.

Circadian rhythms and exercise - re-setting the clock in metabolic disease

Perturbed diurnal rhythms are becoming increasingly evident as deleterious events in the pathology of metabolic diseases. Exercise is well characterized as a crucial intervention in the prevention and treatment of individuals with metabolic diseases. Little is known, however, regarding optimizing the timing of exercise bouts in order to maximize their health benefits. Furthermore, exercise is a potent modulator of skeletal muscle metabolism, and it is clear that skeletal muscle has a strong circadian profile. In humans, mitochondrial function peaks in the late afternoon, and the circadian clock might be inherently impaired in myotubes from patients with metabolic disease. Timing exercise bouts to coordinate with an individual's circadian rhythms might be an efficacious strategy to optimize the health benefits of exercise. The role of exercise as a Zeitgeber can also be used as a tool in combating metabolic disease. Shift work is known to induce acute insulin resistance, and appropriately timed exercise might improve health markers in shift workers who are at risk of metabolic disease. In this Review, we discuss the literature regarding diurnal skeletal muscle metabolism and the interaction with exercise bouts at different times of the day to combat metabolic disease.

US acculturation and poor sleep among an intergenerational cohort of adult Latinos in Sacramento, California

Acculturation may shape the disproportionate burden of poor sleep among Latinos in the United States. Existing studies are limited by unidimensional acculturation proxies that are incapable of capturing cultural complexities across generations. Understanding how acculturation relates to sleep may lead to the identification of modifiable intervention targets. We used multivariable regression and latent class methods to examine cross-sectional associations between a validated multidimensional scale of US acculturation and self-reported poor sleep measures. We analyzed an intergenerational cohort: first-generation (GEN1) older Latinos (Sacramento Area Latino Study on Aging; N = 1,716; median age: 69.5) and second-generation (GEN2) middle-aged offspring and relatives of GEN1 (Niños Lifestyle and Diabetes Study; N = 670; median age: 54.0) in Sacramento, California. GEN1 with high US acculturation, compared with high acculturation towards another origin/ancestral country, had less restless sleep (prevalence ratio [PR] [95% confidence interval (CI)]: 0.67 [0.54, 0.84]) and a higher likelihood of being in the best sleep class than the worst (OR [95% CI]: 1.62 [1.09, 2.40]), but among nonmanual occupations, high intergenerational US acculturation was associated with more general fatigue (PR [95% CI: 1.86 [1.11, 3.10]). GEN2 with high intergenerational US acculturation reported shorter sleep (PR [95% CI]: 2.86 [1.02, 7.99]). High US acculturation shaped sleep differentially by generation, socioeconomic context, and intergenerational acculturative status. High US acculturation was associated with better sleep among older, lower socioeconomic Latinos, but with shorter sleep duration among middle-aged, higher socioeconomic Latinos; results also differed by parental acculturation status. Upon replication, future studies should incorporate prospective and intergenerational designs to uncover sociobehavioral pathways by which acculturation may shape sleep to ultimately inform intervention efforts.

The Intersection of Sleep Apnea and Severe Mental Illness in Veterans

BACKGROUND

Individuals with serious mental illness (SMI) have a high prevalence of risk factors for sleep apnea, but these risk factors often go unrecognized, partly due to the overlap among sleep apnea, somatic conditions, and symptoms (e.g., obesity, daytime sleepiness), leading to potential under-recognition of sleep apnea in a high-risk population.

OBJECTIVE

The objective of our study was to compare sleep apnea prevalence and clinical features among Veterans with and without SMI.

METHOD

Data for the current analyses were drawn from an administrative dataset of 33,818 United States Military Veterans with a primary care visit in calendar year 2007. The medical record data included demographic characteristics, and medical, psychiatric, and sleep diagnoses.

RESULTS

Veterans with SMI had a significantly higher prevalence of sleep apnea than those without SMI. Younger Veterans with SMI had a higher prevalence of sleep apnea relative to older Veterans with SMI and Veterans with SMI and sleep apnea had a greater number of medical comorbidities than Veterans with SMI and no sleep apnea.

CONCLUSION

In a large sample of Veterans, those with SMI were at greater risk of having comorbid sleep apnea. Furthermore, Veterans with comorbid SMI and sleep apnea were at greater risk for increased rates of comorbid medical disorders. Sleep apnea appears to be a key risk factor for increased morbidity in Veterans with an SMI diagnosis, highlighting the importance of treating sleep apnea in a challenging patient population.

Intensifying sleep slow oscillations does not improve metabolic control in healthy men

Impaired sleep quality and sleep loss compromise glucose homeostasis and metabolic function, but the mechanisms linking sleep and metabolic health are largely unclear. In order to gain insight into the relevance of specific electrophysiological sleep characteristics for metabolic control, we assessed the acute effect on glucose homeostasis as well as energy intake and expenditure of enhancing slow oscillatory activity, a hallmark of slow-wave sleep, by closed-loop auditory stimulation in healthy men. Twenty-two young, normal-weight men underwent an oral glucose tolerance test (oGTT), indirect calorimetry and the assessment of ad-libitum breakfast intake in the morning after nocturnal sleep with or without auditory stimulation in phase with the ongoing rhythmic occurrence of slow oscillation up-states during 210 min of slow-wave sleep in the first night-half. Stimulation vs. no stimulation strongly increased slow oscillatory activity without changing overall sleep structure, but did not alter fasting or oGTT-stimulated measures of glucose homeostasis. Food intake and energy expenditure were likewise comparable between conditions. Findings indicate that in healthy humans electrophysiological sleep quality is tuned to allow for optimal metabolic control. Future studies should investigate the potential of sleep stage-specific interventions to enhance metabolic control and well-being in patients with metabolic ailments.

Sex and race differences in the association between sleep duration and adiposity: the Bogalusa Heart Study

BACKGROUND

Short sleep duration has been consistently associated with obesity. However, few studies in adults have assessed whether this association varies by sex and race.

METHODS

In the 2013-2016 examination of 1116 participants from the biracial Bogalusa Heart Study, habitual sleep duration was measured in categories (<6 hours, 6-7 hours, 7-8 hours, > 8 hours) using self-report. Anthropometry was performed and adiposity was assessed using body mass index (BMI) and waist circumference. Linear regression models estimated the relationship between sleep duration and adiposity adjusting for age, education, employment, bed partner status, depressive symptoms, smoking status, physical activity, and the use of alcohol and sleeping pills. Effect modification by sex and race was examined using cross-product terms in the models and marginal means were reported.

RESULTS

Of 1116 participants (mean age 48.2 years), 58.3% were female, and 31.7% were Black. In adjusted analyses, women sleeping <6 hours had a 3.2 (95% CI 1.4, 5.0) kg/m² greater BMI and 6.1 (1.8, 10.4) cm greater waist circumference compared to women sleeping 7-8 hours. In contrast, men had similar BMIs and waist circumferences regardless of sleep duration (p's for interaction = 0.04 & 0.11). There was no effect modification by race.

CONCLUSIONS

In this sample, lower habitual sleep duration was associated with greater adiposity among women compared to men. Further research is needed to understand the potential mechanisms of the adverse metabolic effects of short sleep in women.

Broken Energy Homeostasis and Obesity Pathogenesis: The Surrounding Concepts

Obesity represents an abnormal fat accumulation resulting from energy imbalances. It represents a disease with heavy consequences on population health and society economy due to its related morbidities and epidemic proportion. Defining and classifying obesity and its related parameters of evaluation is the first challenge toward understanding this multifactorial health problem. Therefore, within this review we report selected illustrative examples of the underlying mechanisms beyond the obesity pathogenesis which is systemic rather than limited to fat accumulation. We also discuss the gut-brain axis and hormones as the controllers of energy homeostasis and report selected impacts of obesity on the key metabolic tissues. The concepts of "broken energy balance" is detailed as the obesity starting key step. Sleep shortage and psychological factors are also reported with influences on obesity development. Importantly, describing such mechanistic pathways would allow clinicians, biologists and researchers to develop and optimize approaches and methods in terms of diagnosis, classification, clinical evaluation, treatment and prognosis of obesity.

Trajectories of health behaviors across early childhood cancer survivorship

OBJECTIVE

The majority of childhood cancer survivors develop at least one late effect subsequent to treatment (eg, cardiovascular disease and obesity). Consistent engagement in recommended health behaviors may mitigate some of these conditions. Researchers have identified early survivorship as a teachable moment, yet few studies have examined positive health behaviors during this period.

METHODS

Families of children with cancer (ages 5-17) were initially recruited following a diagnosis or relapse of cancer. Three years post diagnosis, survivors (n = 82, M_age  = 13.3, SD = 3.7) and their mothers (n = 103, M_age  = 41.1, SD = 7.6) completed a questionnaire assessing exercise, dietary, and sleep patterns among survivors. A follow-up assessment was conducted 2 years later. Mixed models tested change in health behavior over time.

RESULTS

At 3- and 5-year post diagnosis, mother and self-report indicated that few survivors engaged in appropriate levels of low-intensity exercise, fruit/vegetable intake, and dairy consumption. However, most survivors engaged in recommended levels of high intensity exercise, fast food restriction, and sleep. Health behaviors remained stable over time, except for mother report of sleep duration, which decreased (b = -0.6, P < 0.001). Brain tumor diagnosis predicted a larger decrease in self-report of sleep duration compared with other diagnoses (P = 0.04). Income predicted fast food intake such that higher income was associated with decreased intake over time, whereas lower income was associated with increased intake (P = 0.04).

CONCLUSIONS

During early survivorship, several health behaviors fell short of expectations for exercise and diet and did not improve upon reaching 5-year post diagnosis. Providers should evaluate survivors' health behaviors, including sleep, early and often, intervening when necessary.

Sleep deprivation and obesity in adults: a brief narrative review

Background/aims

Obesity and sleep deprivation are two epidemics that pervade developed nations. Their rates have been steadily rising worldwide, especially in the USA. This short communication will explore the link between the two conditions and outline the proposed mechanisms behind their relationship.

Methods

Studies on the topic of sleep and obesity were reviewed, and findings were used to develop a theoretical model for the biological link between short sleep duration and obesity.

Results

Individuals who regularly slept less than 7  hours per night were more likely to have higher average body mass indexes and develop obesity than those who slept more. Studies showed that experimental sleep restriction was associated with increased levels of ghrelin, salt retention and inflammatory markers as well as decreased levels of leptin and insulin sensitivity.

Conclusions

There may be a link between obesity and sleep deprivation. We recommend further investigations are to elucidate the potential mechanisms.

You Snooze, You Win: the PhysioNet/Computing in Cardiology Challenge 2018

The PhysioNet/Computing in Cardiology Challenge 2018 focused on the use of various physiological signals (EEG, EOG, EMG, ECG, SaO₂) collected during polysomnographic sleep studies to detect sources of arousal (non-apnea) during sleep. A total of 1,983 polysomnographic recordings were made available to the entrants. The arousal labels for 994 of the recordings were made available in a public training set while 989 labels were retained in a hidden test set. Challengers were asked to develop an algorithm that could label the presence of arousals within the hidden test set. The performance metric used to assess entrants was the area under the precision-recall curve. A total of twenty-two independent teams entered the Challenge, deploying a variety of methods from generalized linear models to deep neural networks.

The Epidemiology of Sleep and Diabetes

PURPOSE OF REVIEW

To provide an overview of the mechanistic and epidemiologic evidence linking sleep-related exposures, such as short sleep duration, obstructive sleep apnea, shift work, and insomnia, with type 2 diabetes risk in adults.

RECENT FINDINGS

Both poor sleep habits and sleep disorders are highly prevalent among adults with type 2 diabetes. In observational studies, short sleep duration, obstructive sleep apnea, shift work, and insomnia are all associated with higher risk of incident type 2 diabetes and may predict worse outcomes in those with existing diabetes. However, interventional studies addressing sleep abnormalities in populations with or at high risk for type 2 diabetes are scarce. Although common sleep abnormalities are associated with risk of incident type 2 diabetes and worse prognosis in those with established diabetes, there are few randomized trials evaluating the impact of sleep-focused interventions on diabetes, making it difficult to determine whether the relationship is causal.

Stress and Obesity

Many pathways connect stress and obesity, two highly prevalent problems facing society today. First, stress interferes with cognitive processes such as executive function and self-regulation. Second, stress can affect behavior by inducing overeating and consumption of foods that are high in calories, fat, or sugar; by decreasing physical activity; and by shortening sleep. Third, stress triggers physiological changes in the hypothalamic-pituitary-adrenal axis, reward processing in the brain, and possibly the gut microbiome. Finally, stress can stimulate production of biochemical hormones and peptides such as leptin, ghrelin, and neuropeptide Y. Obesity itself can be a stressful state due to the high prevalence of weight stigma. This article therefore traces the contribution of weight stigma to stress and obesogenic processes, ultimately describing a vicious cycle of stress to obesity to stigma to stress. Current obesity prevention efforts focus solely on eating and exercise; the evidence reviewed in this article points to stress as an important but currently overlooked public policy target.