Rest-activity circadian rhythm and sleep quality in patients with binge eating disorder

Sleep quality in eating disorders: A systematic review and meta-analysis

Eating disorders (ED) are psychological disorders characterized by dangerous eating behaviours, including protracted fasting and binge eating. Mental disorders comorbidities (e.g., anxiety and depression), as well as sleep difficulties, are common and might interfere with treatment response. This work investigated sleep quality, circadian preferences, and sleep disorders in ED patients compared to healthy controls (HC) and the impact of ED treatment on patients' sleep. A literature search on Pubmed, Web of Science, Medline, and PsychInfo included 27 studies. Random effect analyses were performed (sample eating disorders = 711; sample healthy controls = 653) and subgroup analyses were calculated based on the ED subgroups: Anorexia Nervosa, Bulimia Nervosa, Binge Eating Disorder. Whole sample analyses showed poorer physiological and subjective sleep quality in patients. Subgroup analyses showed that poorer physiological sleep was present only in anorexia nervosa. Two studies reporting circadian preferences and sleep disorders showed higher evening preference in patients and no differences in apnea prevalence between patients and healthy controls, respectively. Some studies suggested that specialized eating disorder treatments (e.g., Cognitive Behavioural Therapy for ED) can improve sleep quality in patients. Although these findings highlight poorer sleep in patients with ED compared to healthy controls, the mechanisms underlying sleep alterations in eating disorders remain to be identified.

The circadian activity rhythms for elderly inpatients with stroke or motor diseases in a rehabilitation facility and its relationship to physical activity level

Disturbances in the circadian activity rhythms (CARs) of inpatients in rehabilitation facilities delay the recovery of physical and mental functions. The purpose of this study is to elucidate the circadian activity rhythms of hospitalized patients in a rehabilitation facilitie using the synthetic periodic regression analysis, and investigate the relationship between their physical activity levels and CARs.An observational study was conducted. A group of thirty-four inpatients participated in the study by wearing wrist-type activity monitors to measure metabolic equivalents (METs). Using synthetic periodic regression analysis, the CARs were analyzed based on the amount of physical activity throughout the day, and the exercise intensity classification of their physical activity was assessed. In the CARs of the inpatients, the mean physical activity level was 1.23 ± 0.09 METs. The maximum amount was 1.36 ± 0.15 METs. The range was 0.30 ± 0.15 METs. The maximum phase time was 11:48 ± 2:31 h. The longer the duration of physical activity over 1.6 METs, the higher the mean, maximum and range of the CARs. Physical activities with a METs level of 1.6 or higher might have an impact on the mean, maximum, and range of circadian activity rhythms in hospitalized patients.

Supplementary Information

The online version contains supplementary material available at 10.1007/s41105-023-00488-8.

Peripheral clock disruption and metabolic disease: moving beyond the anatomy to a functional approach

Sleep and circadian disruption are associated with an increased risk of metabolic disease, including obesity and diabetes. Mounting evidence indicates that misaligned and/or non-functional clock proteins in peripheral tissues critically contribute to the presentation of metabolic disease. Many of the foundational studies which led to this conclusion have focused on specific tissues such as the adipose, pancreas, muscle, and liver. While these studies have greatly advanced the field, the use of anatomical markers to manipulate tissue-specific molecular clocks may not be representative of the circadian disruption that occurs within the clinical population. In this manuscript, we argue that investigators can gain a better understanding of the consequences of sleep and circadian disruption by targeting groups of cells with a functional relationship, even if those cells go beyond anatomical boundaries. This approach is especially important when considering metabolic outcomes which rely on endocrine signaling molecules, such as leptin, that have multiple sites of action. Through the review of several studies, as well as our own work, this article reframes peripheral clock disruption from a functional approach. We additionally present new evidence that disruption of the molecular clock within all cells expressing the leptin receptor affects leptin sensitivity in a time-dependent manner. Taken together, this perspective aims to provide new insight into the mechanisms leading to metabolic disease associated with circadian disruption and various sleep disorders.

A systematic review with meta-analyses of the relationship between recurrent binge eating and sleep parameters

BACKGROUND

Sleep problems are known to compound the negative effects of other health issues, such as eating disorders and the associated behavior of binge eating. Previous studies suggested associations between binge eating and sleep problems, but the strength of the relationship is unknown.

METHODS

We conducted a systematic review with meta-analyses examining the relationship between binge eating and sleep parameters. We searched for studies in Scopus, PubMed, and PsycInfo. The quality of evidence, including risk of bias, was assessed with adaptations of the Newcastle-Ottawa Scale and the Joanna Briggs Institute Critical Appraisal Checklist for Quasi-Experimental Studies, depending on study design. Data was synthesized as the difference in sleep between people who did or did not have binge eating.

RESULTS

Thirty-one reports of studies met our eligibility criteria. Results are presented in 12 meta-analyses. In the 7 reports of studies (with 4448 participants) that assessed poor overall sleep quality, we found poorer overall sleep quality in people with binge eating compared to people without binge eating, with a standardized mean difference of 0.77 (95% confidence interval [CI] 0.61-0.92; P < 0.001), which is a large effect size. In addition, we found evidence that people with binge eating had significantly greater hypersomnia/daytime sleepiness (7 reports of studies with 4370 participants), insomnia (5 reports of studies with 12,733 participants), and difficulty falling asleep (3 reports of studies with 4089 participants) compared to people without binge eating, with moderate effect sizes (standardized mean differences of 0.57-0.66).

CONCLUSIONS

People with binge eating exhibit poorer overall sleep quality compared to people without binge eating, and may also exhibit greater hypersomnia/daytime sleepiness, insomnia, and difficulty falling asleep. It is recommended that healthcare professionals routinely screen for poor overall sleep quality when treating people with binge eating-and address sleep difficulties when present.

Theoretical construct into blocks of actigraphic-derived sleep parameters

Actigraphic parameters can provide indication of people's sleep quality during their daily lives. However, there is a need for clear guidelines on the understanding of the different actigraphic parameters. The present study aims to propose a conceptual and theoretical framework for known actigraphic-derived parameters, which is able to describe the alternation between rest and wake phases during the nocturnal sleep, explaining their main characteristics and interrelations that can be replicated in future studies. Forty Sport Sciences students at the University of Milan (20 males; mean age ± SD, 22 ± 3 y) completed the validated Italian version of Morningness-Eveningness Questionnaire (MEQ) and wore an actigraph (Motion Watch 8®, Cambridge Neurotechnology, Cambridge, UK) for seven days. A framework was developed to depict the interactions between the actigraphic parameters and how they objectively describe sleep, according to which the parameters are organized into three different functional blocks related to different aspects of sleep. Correlations analyses were conducted to explore the relationships among the primary actigraphic parameters within and across the functional blocks. The proposed framework is a purely theoretical construct that provides a simple interpretation of known actigraphic parameters guiding researchers and practitioners in the use of these parameters either for research or clinical purposes.

Food addiction and emotional eating are associated with intradaily rest-activity rhythm variability

PURPOSE

The aim of the present investigation was to study the associations among parameters characterizing eating behavior and actimetry-derived indices of circadian rhythm of motor activity.

METHODS

The study involved 81 healthy participants (average age: 21.5 ± 9.6 y, women: 77.8%). Each study participant provided personal data, filled out the Yale Food Addiction Scale and the Dutch Eating Behavior Questionnaire, and wore a wrist actimeter for 7 consecutive days to record motor activity. Using time series treatments, we obtained: (a) three cosinor-derived parametric indices [Medline Estimating Statistics of Rhythm (MESOR), amplitude, and acrophase], and (b) four non-parametric indices [interdaily stability, intradaily variability (I.V.), most active 10-h period (M10), and least active 5-h period] characterizing the 24-h rhythm of motor activity. A multiple regression analysis adjusted for age, sex, and BMI was performed to assess the associations among the studied indicators.

RESULTS

It was shown that I.V. is a predictor of symptoms of food addiction (β = 0.242, P = 0.037) and emotional eating (β = 0.390, P = 0.004), MESOR is a predictor of symptoms of food addiction (β = 0.342, P = 0.003), and M10 predicts restraint (β = 0.257, P = 0.015) and emotional eating (β = 0.464, P = 0.001).

CONCLUSION

It was shown for the first time that an increase in symptom counts of food addiction is associated with an increase in the average level and fragmentation of 24-h rhythm of motor activity.

LEVEL OF EVIDENCE

Level V, cross-sectional descriptive study.

A biobehavioral circadian model of restrictive eating and binge eating

Caloric consumption occurs in rhythms, typically during daytime, waking hours, marked by peaks at mealtimes. These rhythms are disrupted in individuals with eating disorders; mealtime peaks are blunted and delayed relative to sleep/waketimes. Individuals with eating disorders also tend to experience an overall phase delay in appetite; they lack hunger earlier in the day and experience atypically high hunger later in the day, the latter of which may culminate in binge-eating episodes. This disruptive appetitive behavior-early in the day restrictive eating and later in the day binge eating-may be partially accounted for by circadian disruptions, which play a role in coordinating appetitive rhythms. Moreover, restrictive eating and binge eating themselves may further disrupt circadian synchronization, as meal timing serves as one of many external signals to the central circadian pacemaker. Here, we introduce the biobehavioral circadian model of restrictive eating and binge eating, which posits a central role for circadian disruption in the development and maintenance of restrictive eating and binge eating, highlighting modifiable pathways unacknowledged in existing explanatory models. Evidence supporting this model would implicate the need for biobehavioral circadian regulation interventions to augment existing eating disorder treatments for individuals experiencing circadian rhythm disruption. PUBLIC SIGNIFICANCE: Existing treatments for eating disorders that involve binge eating and restrictive eating mandate a regular pattern of eating; this is largely responsible for early behavioral change. This intervention may work partly by regulating circadian rhythm and diurnal appetitive disruptions. Supplementing existing treatments with additional elements specifically designed to regulate circadian rhythm and diurnal appetitive rhythms may increase the effectiveness of treatments, which presently do not benefit all who receive them.

A matter of time: A systematic scoping review on a potential role of the circadian system in binge eating behavior

Background

Emerging research suggests that food intake timing, eating behavior and food preference are associated with aspects of the circadian system function but the role that the circadian system may play in binge eating (BE) behavior in humans remains unclear.

Objective

To systematically evaluate the evidence for circadian system involvement in BE behavior.

Methods

Systematic searches of PubMed, EMBASE, and Scopus were performed for reports published from inception until May 2020 (PROSPERO Registration CRD42020186325). Searches were conducted by combining Medical Subject Headings related to the circadian system, BE behavior, and/or interventions. Observational and interventional studies in humans with BE behavior published in peer-review journals in the English language were included. Studies were assessed using quality and risk of bias tools (AXIS, ROB 2.0, or ROBINS).

Results

The search produced 660 articles, 51 of which were included in this review. Of these articles, 46 were observational studies and 5 were interventional trials. Evidence from these studies suggests that individuals with BE behavior tend to have more food intake, more binge cravings, and more BE episodes later in the day. Hormonal and day/night locomotor activity rhythm disturbances may be associated with BE behavior. Furthermore, late diurnal preference ("eveningness") was associated with BE behavior and chronobiological interventions that shift the circadian clock earlier (e.g., morning bright light therapy) were found to possibly decrease BE behavior. Substantive clinical overlap exists between BE and night eating behavior. However, there is a significant knowledge gap regarding their potential relationship with the circadian system. Limitations include the lack of studies that use best-established techniques to assess the chronobiology of BE behavior, heterogeneity of participants, diagnostic criteria, and study design, which preclude a meta-analytic approach.

Conclusion

Current evidence, although limited, suggests that the circadian system may play a role in the etiology of BE behavior. Further mechanistic studies are needed to fully characterize a potential role of the circadian system in BE behavior. A chronobiological approach to studying BE behavior may lead to identification of its neurobiological components and development of novel therapeutic interventions.

Systematic review registration

[https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020186325], identifier [CRD42020186325].

Melatonergic agents influence the sleep-wake and circadian rhythms in healthy and psychiatric participants: a systematic review and meta-analysis of randomized controlled trials

Exogenous melatonergic agents are widely used to treat insomnia and sleep disturbance. Several studies have shown that they might also modulate circadian rhythms. The purpose of this systematic review and meta-analysis was to summarize current knowledge about the effects of melatonin supplements and melatonin agonists on the sleep-wake cycle as well as on the circadian rhythm of melatonin in healthy participants and in patients with psychiatric disorders. The following electronic databases were searched: EMBASE, PubMed, Web of Science, CINAHL, and Cochrane Library. Of the 12,719 articles, we finally selected 30 studies including 1294 healthy participants and 8 studies including 687 patients with psychiatric disorders. Cochrane risk of bias tool was used to assess the risk of bias. Using meta-ANOVA, studies on healthy participants showed advancing effects of melatonergic supplements and agonists on sleep-wake cycle according to dosing time and dosage, despite the fact that the original individual melatonin rhythm was within a normal range (fixed effect model standardized mean difference [95% Confidence Interval] = -0.639[-0.968 to -0.310]). In a limited number of randomized controlled trials with psychiatric patients, the findings seemed similar to those with healthy participants, despite the psychiatric disorders and treatment related factors affecting circadian rhythms. Given the unmet clinical need for evidence-based treatments to correct circadian rhythms in psychiatric disorders, efficacy of melatonergic agents seen in healthy participants, and similarity of findings among psychiatric patients, large scale, well-designed randomized controlled trials are needed to test efficacy on circadian parameters in psychiatric disorders.

Sensor technology in eating disorders research: A systematic review

OBJECTIVE

Sensor technologies offer exciting potential to objectively measure psychopathological correlates of eating pathology and eating disorder (ED) research utilizing sensors has rapidly proliferated in the past several years. The aims of the present review are: (1) characterize the types of sensors that have been utilized in ED research, (2) identify the psychopathological factors relevant to EDs that have been assessed using sensors, (3) describe the data supporting the validity and reliability of these sensors, (4) discuss limitations associated with these sensors, and (5) identify gaps that persist within the ED literature with regard to use of sensor technologies.

METHOD

A systematic search was conducted of PubMed, PsycINFO, Web of Science, ProQuest, and "gray" literature sources. Eligible publications were empirical studies that utilized sensors to measure at least one psychological variable among clinical ED populations.

RESULTS

Sensors have been utilized with ED samples to measure eating behaviors, physical activity, sleep, autonomic nervous system activity, eyeblink startle response, visual attention, and visual-haptic object integration. The reliability and validity of these sensors varies widely and there are a number of significant gaps that remain in the literature with regard to the types of sensors utilized, context in which sensors have been used, and populations studied.

DISCUSSION

The existing literature utilizing sensors within ED research largely support the feasibility and acceptability of these tools. Sensors should continue to be utilized within the field, with a specific focus on examining the reliability and validity of these tools within ED samples and increasing the diversity of samples studied.

PUBLIC SIGNIFICANCE STATEMENT

Sensor technologies, such as those included in modern smartwatches, offer new opportunities to measure factors that may maintain or contribute to symptoms of eating disorders. This article describes the types of sensors that have been used in eating disorders research, challenges that may arise in using these sensors, and discusses new applications of these sensors that may be pursued in future research.

Chronotype Profile, Stress, Depression Level, and Temporomandibular Symptoms in Students with Type D Personality

Background: Despite a growing interest in the types of human circadian activity, different chronotypes and personality-related issues have been rarely studied. It has already been emphasized that ‘stress personality’ is considered a risk factor for certain psychosomatic diseases and may be a temporomandibular disorders (TMDs) predictor. Therefore, an attempt has been made to analyze the chronotypes, stress levels, stress factors, and the occurrence of depression and TMDs in students with type D personalities. People with this personality trait tend to experience negative emotions more—depression, anxiety, anger, or hostility—yet may have a negative image of themselves and report somatic complaints. Aim: The aim of this study was to analyze the importance of the chronotype profile for the level of stress perceived, as well as for the occurrence of depression and TMDs in people with type D personalities. Material and Methods: The study has been conducted on a group of 220 physical therapy students. The study group G1 consisted of 110 participants with type D personalities, the control group G2 consisted of the same number of participants without the stress personality. All participants have been analyzed for the chronotype (MEQ), stress perception (PSS10), the occurrence of depression (Beck scale-BDI), the occurrence of TMDs symptoms and have completed the stress factor assessment questionnaire during the study, followed by DS14 questionnaire—a tool for assessing the prevalence of type D personality. Results: In students with type D personalities (G1), the definitely evening and evening chronotypes have been significantly more predominant than in the control group (G2). A significantly higher number of stressors and TMDs symptoms have been observed in the respondents from the G1 group than in the control group (<0.001). Univariate logistic regression analysis showed that type D personality was strongly associated with a more frequent occurrence of all TMD symptoms. Additionally, a significant influence of the evening chronotype on the occurrence of type D personality was observed. Among the potential confounding variables, female gender and a mild and moderate degree of depression have an impact on the occurrence of type D personality (p < 0.05). In the multivariate model, adjusted with the above-mentioned factors, an increased risk of the type D personality trait was found. Conclusion: The evening chronotype and type D personality may imply greater feelings of stress, greater depression, and more frequent symptoms of TMDs in young adults.

Role of Melatonin in the Management of Sleep and Circadian Disorders in the Context of Psychiatric Illness

PURPOSE OF REVIEW

We present a review of research on the role of melatonin in the management of sleep and circadian disorders, stressing current overall view of the knowledge across psychiatric disorders.

RECENT FINDINGS

Dysregulation of sleep and circadian rhythms has been established in several psychiatric and neurocognitive disorders for long. Recent research confirms this finding consistently across disorders. The secretion of melatonin in schizophrenia and neurocognitive disorders is reduced due to a smaller volume and enlarged calcification of the pineal gland. On the other hand, melatonin dysregulation in bipolar disorder may be more dynamic and caused by light-sensitive melatonin suppression and delayed melatonin secretion. In both cases, exogenous melatonin seems indicated to correct the dysfunction. However, a very limited number of well-designed trials with melatonin to correct sleep and circadian rhythms exist in psychiatric disorders, and the evidence for efficacy is robust only in autism, attention deficit hyperactivity disorder (ADHD), and neurocognitive disorders. This topic has mainly not been of interest for recent work and well-designed trials with objective circadian parameters are few. Overall, recent studies in psychiatric disorders reported that melatonin can be effective in improving sleep parameters such as sleep onset latency, sleep efficiency, and sleep quality. Recent meta-analysis suggests that optimal dosage and dosing time might be important to maximize the efficacy of melatonin. The knowledge base is sufficient to propose well-designed, larger trials with circadian parameters as inclusion and outcome criteria. Based on the partly fragmentary information, we propose testing efficacy in disorders with neurocognitive etiopathology with later and higher dosing, and affective and anxiety disorders with lower and earlier dosing of melatonin. Melatonin is promising for the correction of sleep and circadian abnormalities in psychiatric disorders. However, research results on its effect are still few and need to be accumulated. For effective use of melatonin, it is necessary to consider the appropriate dosage and administration time, depending on the individual abnormality of sleep and circadian rhythms.

Relevance of Objective Measures in Psychiatric Disorders-Rest-Activity Rhythm and Psychophysiological Measures

PURPOSE OF REVIEW

We present a review of recent methods of objective measurement in psychiatry and psychology with a focus on home monitoring and its utility in guiding treatment.

RECENT FINDINGS

For individualized diagnostics and treatment of insomnia, actigraphy can generate clinically useful graphical presentations of sleep timing and patterns. Psychophysiological measures may complement psychometrics by tracking parallel changes in physiological responses and emotional functioning, especially during therapy for trauma symptoms and emotion regulation. It seems that rather than defining universal cut-offs, an individualised range of variability could characterize treatment response. Wearable actigraphy and psychophysiological sensors are promising devices to provide biofeedback and guide treatment. Use of feasible and reliable technology during experimental and clinical procedures may necessitate defining healthy and abnormal responses in different populations and pathological states. We present a "call for action" towards further collaborative work to enable large scale use of objective measures.

Sleep habits and weight status in Brazilian children aged 4-6 years of age: the PREDI study

OBJECTIVES

To evaluate the association of sleep habits with the weight status of children aged 4-6 years.

METHODS

Data were obtained from the PREDI Study, a Brazilian birth cohort study. The current study was carried out in the homes of the participants during two follow-ups: 2016/17 and 2018. The participants were submitted to anthropometric assessment and demographic, socioeconomic and sleep data were obtained. The child's sleep habits were self-reported by the mother or caregiver on the day of the visit and included information on the following sleep habits during the past week: bedtime routine, rhythmicity, and separation affect determined with the Sleep Habits Inventory for Preschool Children and the Sleep Habits Inventory. Logistic regression and gamma-log regression analyses were used to examine the association of sleep habits with excess body weight of children in the two follow-ups according to sex.

RESULTS

Of the 217 and 185 children included in 2016/17 and 2018, respectively, 66 (30.6%) and 48 (25.9%) had a BMI >85th percentile at 4-6 years, respectively. The median rhythmicity score was higher in children with excess body weight (p = 0.05). Adjusted analysis showed that rhythmicity was associated with excess body weight of girls at ages 4-5 years (OR = 1.42, 95% CI: 1.09-1.86, p = 0.009) and 6 years (OR = 1.32, 95% CI: 1.06-1.65, p = 0.015), even after adjustment for other important covariates. Additionally, the sleep habit "separation affect" was inversely associated with the child's BMI in boys (β = -0.005, 95% CI: -0.010-0.000, p = 0.037).

CONCLUSIONS

In the present study, rhythmicity problems were associated with increased odds of girls aged 4-6 years having excess body weight. These results are important from a public health perspective since strategies aimed at preventing excess body weight in children need to consider the child's sleep quality as a potential risk factor, especially rhythmicity.

The case for investigating a bidirectional association between insomnia symptoms and eating disorder pathology

Many people with eating disorders (EDs) report symptoms of insomnia (i.e., frequent difficulty falling asleep, staying asleep, and/or early morning wakening) and sleep problems have been linked to alterations in eating behaviors; however, mechanisms of these bidirectional associations remain poorly understood and under researched. This is a problem because higher insomnia symptom severity is a risk factor for the onset and perpetuation of anxiety, mood, trauma, and substance use disorders and, potentially, ED symptoms. Furthermore, insomnia symptoms may hinder recovery and increase relapse rates following successful psychotherapy. In this article, we describe potential mechanisms underlying bidirectional associations between insomnia and eating psychopathology that may contribute to the etiology and maintenance of both disorders. We suggest novel directions for future research to characterize the association between dysregulated sleep and ED symptoms and to evaluate impacts of insomnia symptoms on relapse and recovery for people with co-occurring pathology. Finally, we discuss options for testing the incorporation of existing evidence-based treatments for insomnia disorder (e.g., Cognitive-Behavioral Therapy for Insomnia) with ED care. Overall, insomnia symptoms present a promising intervention point for ED treatment that has not been systematically tested, yet would be highly feasible to address in routine clinical care.

Association of Sleep Quality With Greater Left Ventricular Mass in Children Aged 9 to 11 Years

OBJECTIVE

Research has consistently found associations between sleep characteristics and cardiovascular disease risk in children, adolescents, and adults. Although primarily investigated in clinical samples (e.g., in those with sleep disorders), greater left ventricular mass is associated with poor sleep quality in nonclinical adult populations as well; however, this has not been evaluated in children or adolescents. Our study aim was to consider the relationship between objectively measured sleep characteristics and left ventricular mass in children.

METHODS

We assessed sleep and cardiac structure in a biracial sample of 9- to 11-year-old children (n = 176; 41% White, 59% Black; 50% female). Sleep was assessed with actigraphy for five nights. Cardiac dimensions were assessed using echocardiography.

RESULTS

After adjusting for covariates, we found that poor sleep quality was associated with significantly greater left ventricular mass (β = 0.13, t(167) = 2.14, p = .034, Cohen d = 0.16, for activity during sleep; β = 0.15, t(167) = 2.43, p = .016, Cohen d = 0.18, for sleep fragmentation). Other cardiac dimensions (namely, relative wall thickness and right ventricular dimension) were also significantly associated with sleep characteristics. Notably, associations did not differ as a function of sex or race.

CONCLUSIONS

The present findings are novel and unique because no prior reports have systematically documented the association between poor sleep quality with potentially detrimental cardiac remodeling in a nonclinical sample of children. However, the novelty and importance of these findings require additional research for confirmation.

Biological Rhythm and Chronotype: New Perspectives in Health

The circadian rhythm plays a fundamental role in regulating biological functions, including sleep–wake preference, body temperature, hormonal secretion, food intake, and cognitive and physical performance. Alterations in circadian rhythm can lead to chronic disease and impaired sleep. The circadian rhythmicity in human beings is represented by a complex phenotype. Indeed, over a 24-h period, a person’s preferred time to be more active or to sleep can be expressed in the concept of morningness–eveningness. Three chronotypes are distinguished: Morning, Neither, and Evening-types. Interindividual differences in chronotypes need to be considered to reduce the negative effects of circadian disruptions on health. In the present review, we examine the bi-directional influences of the rest–activity circadian rhythm and sleep–wake cycle in chronic pathologies and disorders. We analyze the concept and the main characteristics of the three chronotypes.

Sex Differences in Rest-Activity Circadian Rhythm in Patients With Metabolic Syndrome

Rest-Activity circadian Rhythm (RAR) can be used as a marker of the circadian timing system. Recent studies investigated the relationship between irregular circadian rhythms and cardiovascular risk factors such as hypertension, obesity, and dyslipidemia. These factors are related to the Metabolic Syndrome (MS), a clustering of metabolic risk factors that increases the risk of several cardiovascular and metabolic diseases. This cross-sectional analysis aimed to explore the RAR characteristics by actigraphy in subjects with MS, particularly in relation to sex and MS parameters, using parametric and non-parametric analyses. Distinguishing the characteristics of RAR based on sex could prove useful as a tool to improve the daily level of activity and set up customized activity programs based on each person’s circadian activity profile. This study showed that female participants exhibited higher values than male participants in the Midline Estimating Statistic of Rhythm (MESOR) (243.3 ± 20.0 vs 197.6 ± 17.9 activity count), Amplitude (184.5 ± 18.5 vs 144.2 ± 17.2 activity count), which measures half of the extent of the rhythmic variation in a cycle, and the most active 10-h period (M10) (379.08 ± 16.43 vs 295.13 ± 12.88 activity count). All these parameters are indicative of a higher daily activity level in women. Female participants also had lower Intradaily Variability (IV) than male participants (0.75 ± 0.03 vs 0.85 ± 0.03 activity count), which indicates a more stable and less fragmented RAR. These preliminary data provide the first experimental evidence of a difference in RAR parameters between male and female people with MS.

Anxiety, sleep quality, and binge eating in overweight or obese adults

OBJECTIVE

To analyze the relationship of anxiety to binge eating and sleep quality in overweight or obese adults.

METHOD

Transversal study, conducted between May 2015 and January 2017, with an intentional sample composed of literate individuals of both sexes, aged 20 to 59 years, who presented body mass index higher or equal to 25 kg/m2. State-Trait Anxiety Inventory, Binge Eating Scale, and Pittsburgh Sleep Quality Index were employed. Pearson or Spearman correlation coefficient was adopted for data analysis, according to its distribution.

RESULTS

The sample comprised 130 individuals. The overall and young adults' samples presented a positive correlation between anxiety and binge eating scores (p=0.0011) and sleep quality score (p=0.0081). Adults who were 45 or older presented an inverse relation between age and anxiety (p=0.0003).

CONCLUSION

The overall sample and young adults who presented higher anxiety state had higher indexes of binge eating and a worse sleep quality, whereas for middle-aged adults, higher age was related to a lower anxiety score. Brazilian Registry of Clinical Trials (Registro Brasileiro de Ensaios Clínicos): n° RBR-47kfxh.

Binge Eating Disorder: What Is the Role of Physical Activity Associated with Dietary and Psychological Treatment?

Binge eating patients present lower physical activity levels, which could be associated with lower exercise capacity. Specific physical activity can ensure broad beneficial results relating to eating disorders, depression, and body mass index (BMI) in bulimia; however, research on binge eating disorder (BED) is scarce. Our study aimed to investigate the effects of specific training as an addition to conventional treatment of eating disorder symptoms, anthropometric characteristics, and physical performance. Nineteen women with BED were included in a dietary and cognitive-behavioral therapy program. After medical examination, 10 women carried out Combined Aerobic and Anaerobic Exercise Training in addition to conventional treatment (CAAET group), whereas the remaining 9 followed the conventional treatment alone (CTRL group). All of the measurements were assessed before and after six months of treatment. In both groups, we observed a significant decrease in binge episodes, weight, and body mass index, and an increase in exercise capacity. Moreover, the CAAET group presented a greater improvement in aerobic performance than that observed in the CTRL group. Our results suggest that both interventions similarly improved BED symptoms. The addition of physical activity could be important in the long-term maintenance of both weight loss and reduction in binge episodes in BED patients.

The Relationship between Childhood Trauma, Eating Disorders, and Sleep Quality among Registered Hospital Nurses in South Korea

This cross-sectional study examined the relationship between childhood trauma, eating disorders, and sleep quality among registered hospital nurses in South Korea. Self-report questionnaires were answered by 279 nurses from six general hospitals. Factors affecting sleep quality were analyzed with a linear regression analysis. The factors that influenced sleep quality included age, alcohol consumption, chronic disease, BMI, and emotional abuse in childhood trauma. Hospital nurses need to increase their sleep health knowledge to maintain a healthy lifestyle while working as a nurse. Therefore, hospital and nursing managers should consider strategies to prevent and intervene in the sleep quality threats attributed to the adverse childhood experiences of hospital nurses.

Late and Instable Sleep Phasing is Associated With Irregular Eating Patterns in Eating Disorders

BACKGROUND

Sleep problems are common in eating disorders (EDs).

PURPOSE

We evaluated whether sleep-phasing regularity associates with the regularity of daily eating events.

METHODS

ED patients (n = 29) completed hourly charts of mood and eating occasions for 2 weeks. Locomotor activity was recorded continuously by wrist actigraphy for a minimum of 10 days, and sleep was calculated based on periods of inactivity. We computed the center of daily inactivity (CenDI) as a measure of sleep phasing and consolidation of the daily inactivity (ConDI) as a measure of daily sleep rhythm strength. We assessed interday irregularities in the temporal structure of food intake using the standard deviation (SD) of frequency (IFRQ), timing (ITIM), and interval (IINT) of food intake. A self-evaluation of other characteristics included mood, anxiety, and early trauma.

RESULTS

A later phasing of sleep associated with a lower frequency of eating (eating frequency with the CenDI rho = -0.49, p = .007). The phasing and rhythmic strength of sleep correlated with the degree of eating irregularity (CenDI with ITIM rho = 0.48, p = .008 and with IINT rho = 0.56, p = .002; SD of CenDI with ITIM rho = 0.47, p = .010, and SD of ConDI with IINT rho = 0.37, p = .048). Childhood Trauma Questionnaire showed associations with variation of sleep onset (rho = -0.51, p = .005) and with IFRQ (rho = 0.43, p = .023).

CONCLUSIONS

Late and variable phasing of sleep associated robustly with irregular pattern of eating. Larger data sets are warranted to enable the analysis of diagnostic subgroups, current medication, and current symptomatology and to confirm the likely bidirectional association between eating pattern stability and the timing of sleep.

Reduced Neuromuscular Performance in Night Shift Orthopedic Nurses: New Insights From a Combined Electromyographic and Force Signals Approach

The effect of sleep–wake rhythm disruption on neuromuscular control and muscle fatigue has received little attention. Because nurse shift work is so varied, including overnight duty, rotating shift schedules, early awakening, and interrupted nocturnal sleep, it offers an interesting model to study this paradigm. It has been investigated so far using only subjective markers. A combined approach based on the simultaneous analysis of surface electromyographic (sEMG) and force signals can objectively detect possible deficits in neuromuscular control and muscle fatigue. With this study we investigated neuromuscular activation and muscle contraction capacity at submaximum and maximum level in nurses working two night-shift schedules and compared them to levels in nurses working entirely in day shifts. Sleep quality and activity levels were also assessed. The study sample was 71 nurses grouped by their shift work schedule: night shift for 5 days (NS₅, n = 46), night shift for 10 days (NS₁₀, n = 9), and only day/swing shift (DS, n = 16). Before and after the shift-work cycle, maximum voluntary contraction (MVC) force and muscle activation, neuromuscular control, and muscle fatigability were measured in the finger flexor muscles. Activity level and sleep quality during the shift-work cycle were recorded with a wrist actigraph. After the shift-work cycles, MVC force and muscle activation were decreased (−11 ± 3% and −33 ± 3%, p < 0.001) as was neuromuscular control (−36 ± 8%, p = 0.007), whereas muscle fatigability was increased (+ 19 ± 9%, p = 0.006) in the NS₅ and the NS₁₀ group. Sleep quality was lower in the NS₅ and the NS₁₀ group (−8 ± 1.8% and −15%3, respectively, p < 0.001), while the activity level for the three groups was similar. There was a clear reduction in neuromuscular control and an increase in muscle fatigue in the nurses working the night shift. These findings may inform of work schedule planning or recommendations for devising new recovery strategies to counteract neuromuscular alterations in night shift nurses.

Rest-activity rhythm in breast cancer survivors: an update based on non-parametric indices

Recently we evaluated by actigraphy the rest-activity circadian rhythm (RAR) in breast cancer (BC) survivors at 5 years from primary diagnosis, as well as in a control group with similar age and body mass index (BMI). RAR, analyzed by Cosinor method, resulted significantly different in BC survivors compared to healthy subjects: BC survivors showed lower values of MESOR and Amplitude (A), while acrophase (φ) was similar in the two groups. Now, using non-parametric methods we have detected Interdaily Stability (IS), Intradaily Variability (IV), nocturnal activity (L5), and daily activity (M10) on the same sample of previous study: 15 BC survivors at 5 years from the primary diagnosis (mean age = 56.7 ± 6.6 yrs; mean BMI = 24.5 ± 3.8 Kg/m²) and 13 healthy controls (mean age = 54.4 ± 7.2 yrs; mean BMI = 25.2 ± 2.8 Kg/m²). The non-parametric indices showed that in BC-group IV was significantly higher than in Ctrl-group (0.86 vs. 0.65 a.u. in BC and Ctrl, respectively; p <.01), while L5 (11.27 vs. 34.41 a.c. in BC and Ctrl, respectively; p <.0001) and M10 (326.82 vs. 428.07 a.c. in BC and Ctrl, respectively; p <.01) were significantly lower compared to Ctrl-group. The data suggest that BC patients need constant clinical assessment of RAR characteristics along the years following the primary diagnosis. The analysis of RAR in all its components, parametric and non-parametric, is important to detect alterations in the sleep-wake cycle and can be useful for developing new strategies for health protection, such as structured and tailored physical activity programs, to improve circadian activity level in order to raise the quality of life in BC survivors.

Effect of chronotype on academic achievement in a sample of Italian University students

Circadian rhythms play an important role in biological function; their expression differs across individuals; three chronotypes are distinguished: Morning- [MT], Evening- [ET], and Neither- [NT] type. MT achieve peak activation in the first part of the day and are generally more conscientious and achievement-oriented than ET, which reach their best during the second half of the day and express a higher intelligence. University class schedules can sometimes conflict with ET circadian preferences, compromising their academic performance compared with their MT classmates. Conversely, MT students, being more aligned with their daily schedule, might be more advantaged in their mental performance. The attitudes and performance of NT students are little considered. No studies to date have investigated academic achievement in relation to chronotype in an Italian student population. To fill this gap, this study examined the relationship between chronotype and academic performance in a population of Motor Science Faculty in Milan, differentiating achievement in theoretical and practical subjects by chronotype. The study population was 423 university students (290 males and 133 females) and categorized by chronotype according to Morningness-Eveningness Questionnaire (MEQ) scores. Student transcripts were reviewed to obtain exam grades on three practical and three theoretical subjects. The interaction between MEQ score or chronotypes and mean exam grade was evaluated using one-way ANOVA. The mean grades on the theoretical and practical exams were higher for the MT than for either the ET or the NT students. The NT students (24.8 ± 0.1) had lower mean grades for the theoretical subjects than either the MT (26.3 ± 0.4) or the ET (25.3 ± 0.2) students, while the ET (26.6 ± 0.2) performed worse than either the MT (27.8 ± 0.2) or the NT students (26.9 ± 0.1) on the practical exams. The same trend was observed for the total sample and when subdivided by sex. In the total sample, significant differences in theoretical and practical exam grades were noted between chronotypes: MT vs ET (p < .002, p < .0006) and MT vs NT (p < .04, p < .003). The differences between the males were significant for the theoretical (p < .006, MT vs NT, p < .002) and the practical subjects (MT vs ET p < .004, MT vs NT, p < .01), but no significant differences were noted between the females. Our findings indicate overall better academic achievement by the MT students, whereas the NT had lower exam grades for the theoretical subjects and the ET performed worse on the practical exams. We speculate that the higher intelligence expressed by the ET students might have helped them compensate the disadvantage on the theoretical but not on practical exams, in which the effect of misalignment between circadian preferences and university class schedule was more evident.

The multidisciplinary therapy in binge eating disorder is able to influence the interdaily stability and sleep quality?

We have recently shown that rest-activity circadian rhythm significantly differed in women with Binge Eating Disorder (BED) compared to the Ctrl group. In details, patients with BED exhibited significantly reduced levels of MESOR and Amplitude with respect to the Ctrl group. In addition, in this previous study, the results of the actigraphic sleep monitoring provided no evidence of differences in sleep parameters between the two groups. We expanded the original sample obtaining a total of 28 volunteered women, 14 BED women, and 14 Ctrl. We recorded in all 28 participants a 5-day actigraphic monitoring to detect the rhythmometric parameters, interdaily stability, intradaily variability, L5, M10, and sleep parameters. During the study, BED's women group kept an individual multidisciplinary therapy lasting five weekly days, from Monday to Friday, consisting in cognitive-behavioral therapy and nutritional program, administered in outpatient care from 8:00 a.m. at 5:00 p.m. The combination of both our previous and current study supports the conclusion that the sleep quality of the BED group is significantly better compared to Ctrl. The non-parametric indexes showed how interdaily stability, significantly correlated to sleep efficiency, was higher in BED group compared to the Ctrl group, indicating a better synchronization of rest-activity circadian rhythm. In conclusion, the maintenance of a regular lifestyle, such as imposed by the multidisciplinary therapy, is important to avoid alterations in the sleep-wake cycle, particularly in patients with eating disorders.

Rest-activity circadian rhythm in breast cancer survivors at 5 years after the primary diagnosis

Rest-activity circadian rhythm (RAR) is a marker of the circadian timing system. Particular attention has been given to RAR characteristics in cancer diseases. Specifically, alterations of RAR parameters have been found, at different stages of clinical pathway, in breast cancer (BC) patients. No studies to date have analyzed RAR alterations in breast cancer survivors several years after the diagnosis. The aim of this study was to determine RAR by actigraphy in a population of BC survivors at 5 years after the primary diagnosis, and to compare their RAR characteristics with healthy controls. The study sample was 28 women: 15 BC survivors at 5 years from the primary diagnosis (BC-group) and 13 healthy controls (Ctrl-group), matched for age and body mass index. All participants have been monitored for 7 days by actigraphy to evaluate RAR. A statistically significant circadian rhythm (T = 24) was found in all 28 subjects (p < .001). The group analysis revealed a significant RAR both in BC- and Ctrl-group (p < .001). The acrophase was not different between the BC- and Ctrl-group (15:09 vs. 15:01 hr:min in BC- and Ctrl-group, respectively). In contrast, the MESOR (Midline Estimating Statistic of Rhythm) and the amplitude were lower in the BC-group with respect to the Ctrl-group. Indeed, the MESOR was 192.0 vs. 276.4 activity counts in BC- and Ctrl-group, respectively (p < .001), while the amplitude was 167.0 vs. 222.6 activity counts in BC- and Ctrl-group, respectively (p < .001). These results provide the first experimental evidence of alterations in RAR parameters in BC survivors at 5 years after the primary diagnosis. Larger studies with a prospective design are needed to assess the role of RAR in the quality of life and prognosis in BC survivors.

Medical Complications of Binge Eating Disorder

Binge eating disorder (BED) is the most common eating disorder and is accompanied by multiple medical comorbidities, many of which are associated with obesity-related diseases. However, the BED itself is likely to confer additional risk factors. BED presents with medical symptoms in virtually every body system and can have devastating consequences on both quality and length of life. This review covers the major comorbidities of BED and highlights areas of ongoing research in this disorder.