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The periodicity of sleep duration – an infradian rhythm in spontaneous living
Wong SN,Halaki M,Chow CM
Nature and Science of Sleep , 2013,
Abstract: Shi Ngar Wong, Mark Halaki, Chin Moi ChowDiscipline of Exercise and Sport Science, University of Sydney, Sydney, NSW, AustraliaAbstract: The sleep–wake cycle is a process not only dictated by homeostatic and circadian factors but also by social and environmental influences. Thus, the total sleep time partly reflects sleep need, which is integral to the dynamics of sleep loss recovery. This study explored the nature of the observed oscillations in total sleep time in healthy adults under spontaneous living conditions. Actigraph-measured sleep data for 13 healthy young male adults were collected over 14 consecutive days and analyzed for habitual sleep duration. The total sleep time periodicity was modeled using the cosinor method for each individual across the 14 days. The findings confirm the existence of periodicity in habitual sleep duration as there were clear periodic patterns in the majority of the participants. Although exclusive to each individual, the observed oscillations may be a resultant response of homeostatic sleep need, circadian timing, and/or social and environmental influences. These findings instigate further indepth studies into the periodicity of sleep duration in healthy individuals to provide a better understanding of sleep need in short versus long sleepers, in predicting work performance, and reducing sleepiness-related accidents following shift work, and how this periodicity may impact sleep treatment outcome in clinical populations.Keywords: sleep regulation, homeostasis, habitual sleep, spontaneous living, healthy males
The nature of sleep examined via the science of sleep
Hussain MV, Shea SA
Nature and Science of Sleep , 2011, DOI: http://dx.doi.org/10.2147/NSS.S21283
Abstract: The nature of sleep examined via the science of sleep Editorial (5359) Total Article Views Authors: Hussain MV, Shea SA Published Date June 2011 Volume 2011:3 Pages 37 - 38 DOI: http://dx.doi.org/10.2147/NSS.S21283 Mohammad Viqar Hussain, Steven Andrew Shea Division of Sleep Medicine, Harvard Medical School and Brigham and Women’s Hospital, Boston, MA, USA The phenomenon of sleep is so curious from almost every vantage point: historical, cultural, scientific, and medical. The Nature and Science of Sleep is a new journal that aims to publish original research and reviews that will help unravel the mysteries of sleep, and improve our understanding of sleep disorders in humans. The success of a new journal can be unpredictable. Ideally there would be a high threshold for publication of only important and robust findings or very well considered reviews, yet the best scientists and authors may be reluctant to put their best work in a new journal because there is a perceived risk that the new journal will not become popular. However, publishing in the Nature and Science of Sleep provides authors with numerous advantages. First, we are committed to making this journal a success. As an example of this, the Nature and Science of Sleep has one of the fastest turnaround times for peer review and editor's approval among medical journals, with an average review plus editorial decision in less than 2 weeks and online publication soon after. Second, we provide open access publishing so that all papers are freely available to anyone in the world directly from the website. Third, our editorial board comprises many of the world's distinguished scientists within the field of sleep research and sleep medicine, which provides a great foundation for this journal. Fourth, we anticipate that in the near future all publications within this journal will be available through PubMed and other searchable databases. Post to: Cannotea Citeulike Del.icio.us Facebook LinkedIn Twitter Other articles by Dr Steven Shea Wake up to insomnia: future approaches to the management of insomnia Readers of this article also read: Role of aliskiren in cardio-renal protection and use in hypertensives with multiple risk factors Subset-directed antiviral treatment of 142 herpesvirus patients with chronic fatigue syndrome Sleep physiology and sleep disorders in childhood Sleep characteristics, sleep problems, and associations of self-efficacy among German university students Impact of lifestyle and technology developments on sleep Short sleep duration is associated with teacher-reported inattention and cognitive problems in healthy school-aged children Sleep patterns and the risk for ADHD: a review Longitudinal study of self-awakening and sleep/wake habits in adolescents The periodicity of sleep duration – an infradian rhythm in spontaneous living Estimating adolescent sleep patterns: parent reports versus adolescent self-report surveys, sleep diaries, and actigraphy
Wake up to insomnia: future approaches to the management of insomnia
Mohammad Tahir Hussain, Steven A. Shea
Nature and Science of Sleep , 2011, DOI: http://dx.doi.org/10.2147/NSS.S15647
Abstract: Wake up to insomnia: future approaches to the management of insomnia Editorial (5507) Total Article Views Authors: Mohammad Tahir Hussain, Steven A. Shea Published Date January 2011 Volume 2011:3 Pages 33 - 35 DOI: http://dx.doi.org/10.2147/NSS.S15647 Mohammad Tahir Hussain, Steven A. Shea Division of Sleep Medicine, Harvard Medical School, Brigham and Women's Hospital, Boston, MA, USA Insomnia is rife. Acutely, almost every individual has experienced a poor night’s sleep, and many short-term remedies for insomnia are tried, including over-the-counter sleep aids and alcohol. Chronic insomnia is the most common sleep disorder, affecting nearly 40 million Americans and accounting for nearly one-third of adults. The annual cost associated with this disorder in the US is estimated at over $15 billion and over $100 billion for indirect costs, such as costs of self-medication, health care-related costs due to exacerbations of comorbid conditions, and costs of reduced productivity. Post to: Cannotea Citeulike Del.icio.us Facebook LinkedIn Twitter Other articles by Dr Steven Shea The nature of sleep examined via the science of sleep Readers of this article also read: Role of aliskiren in cardio-renal protection and use in hypertensives with multiple risk factors Tackling sleeplessness: Psychological treatment options for insomnia Tackling sleeplessness: psychological treatment options for insomnia in older adults Management of insomnia: update and new approaches The nature of sleep examined via the science of sleep Behavioral treatment of insomnia: a proposal for a stepped-care approach to promote public health Impact of lifestyle and technology developments on sleep Sleep patterns and the risk for ADHD: a review Longitudinal study of self-awakening and sleep/wake habits in adolescents The periodicity of sleep duration – an infradian rhythm in spontaneous living
Circadian rhythm sleep disorders
Kolla BP, Auger RR, Morgenthaler TI
ChronoPhysiology and Therapy , 2012, DOI: http://dx.doi.org/10.2147/CPT.S21937
Abstract: cadian rhythm sleep disorders Review (2440) Total Article Views Authors: Kolla BP, Auger RR, Morgenthaler TI Published Date May 2012 Volume 2012:2 Pages 19 - 34 DOI: http://dx.doi.org/10.2147/CPT.S21937 Received: 24 January 2012 Accepted: 27 February 2012 Published: 25 May 2012 Bhanu P Kolla,1,2 R Robert Auger,1,2 Timothy I Morgenthaler1 1Mayo Center for Sleep Medicine, 2Department of Psychiatry and Psychology, Mayo Clinic College of Medicine, Rochester, MN, USA Abstract: Misalignment between endogenous circadian rhythms and the light/dark cycle can result in pathological disturbances in the form of erratic sleep timing (irregular sleep–wake rhythm), complete dissociation from the light/dark cycle (circadian rhythm sleep disorder, free-running type), delayed sleep timing (delayed sleep phase disorder), or advanced sleep timing (advanced sleep phase disorder). Whereas these four conditions are thought to involve predominantly intrinsic mechanisms, circadian dysrhythmias can also be induced by exogenous challenges, such as those imposed by extreme work schedules or rapid transmeridian travel, which overwhelm the ability of the master clock to entrain with commensurate rapidity, and in turn impair approximation to a desired sleep schedule, as evidenced by the shift work and jet lag sleep disorders. This review will focus on etiological underpinnings, clinical assessments, and evidence-based treatment options for circadian rhythm sleep disorders. Topics are subcategorized when applicable, and if sufficient data exist. The length of text associated with each disorder reflects the abundance of associated literature, complexity of management, overlap of methods for assessment and treatment, and the expected prevalence of each condition within general medical practice.
Circadian rhythm sleep disorders  [cached]
Kolla BP,Auger RR,Morgenthaler TI
ChronoPhysiology and Therapy , 2012,
Abstract: Bhanu P Kolla,1,2 R Robert Auger,1,2 Timothy I Morgenthaler11Mayo Center for Sleep Medicine, 2Department of Psychiatry and Psychology, Mayo Clinic College of Medicine, Rochester, MN, USAAbstract: Misalignment between endogenous circadian rhythms and the light/dark cycle can result in pathological disturbances in the form of erratic sleep timing (irregular sleep–wake rhythm), complete dissociation from the light/dark cycle (circadian rhythm sleep disorder, free-running type), delayed sleep timing (delayed sleep phase disorder), or advanced sleep timing (advanced sleep phase disorder). Whereas these four conditions are thought to involve predominantly intrinsic mechanisms, circadian dysrhythmias can also be induced by exogenous challenges, such as those imposed by extreme work schedules or rapid transmeridian travel, which overwhelm the ability of the master clock to entrain with commensurate rapidity, and in turn impair approximation to a desired sleep schedule, as evidenced by the shift work and jet lag sleep disorders. This review will focus on etiological underpinnings, clinical assessments, and evidence-based treatment options for circadian rhythm sleep disorders. Topics are subcategorized when applicable, and if sufficient data exist. The length of text associated with each disorder reflects the abundance of associated literature, complexity of management, overlap of methods for assessment and treatment, and the expected prevalence of each condition within general medical practice.Keywords: circadian rhythm sleep disorders, assessment, treatment
Assessing Periodicity of Periodic Leg Movements During Sleep  [PDF]
Christian Rummel,Heidemarie Gast,Kaspar Schindler,Markus Müller,Frédérique Amor,Christian W. Hess,Johannes Mathis
Frontiers in Human Neuroscience , 2010, DOI: 10.3389/fnhum.2010.00100
Abstract: Background: Periodic leg movements (PLM) during sleep consist of involuntary periodic movements of the lower extremities. The debated functional relevance of PLM during sleep is based on correlation of clinical parameters with the PLM index (PLMI). However, periodicity in movements may not be reflected best by the PLMI. Here, an approach novel to the field of sleep research is used to reveal intrinsic periodicity in inter movement intervals (IMI) in patients with PLM. Methods: Three patient groups of 10 patients showing PLM with OSA (group 1), PLM without OSA or RLS (group 2) and PLM with RLS (group 3) are considered. Applying the “unfolding” procedure, a method developed in statistical physics, enhances or even reveals intrinsic periodicity of PLM. The degree of periodicity of PLM is assessed by fitting one-parameter distributions to the unfolded IMI distributions. Finally, it is investigated whether the shape of the IMI distributions allows to separate patients into different groups. Results: Despite applying the unfolding procedure, periodicity is neither homogeneous within nor considerably different between the three clinically defined groups. Data-driven clustering reveals more homogeneous and better separated clusters. However, they consist of patients with heterogeneous demographic data and comorbidities, including RLS and OSA. Conclusions: The unfolding procedure may be necessary to enhance or reveal periodicity. Thus this method is proposed as a pre-processing step before analyzing PLM statistically. Data-driven clustering yields much more reasonable results when applied to the unfolded IMI distributions than to the original data. Despite this effort no correlation between the degree of periodicity and demographic data or comorbidities is found. However, there are indications that the nature of the periodicity might be determined by long-range interactions between LM of patients with PLM and OSA.
Sleep Duration and Breast Cancer Phenotype  [PDF]
Ali Khawaja,Santosh Rao,Li Li,Cheryl L. Thompson
Journal of Cancer Epidemiology , 2013, DOI: 10.1155/2013/467927
Abstract: Emerging evidence suggests that short sleep is associated with an increased risk of cancer; however, little has been done to study the role of sleep on tumor characteristics. In this study, we evaluated the relationship between sleep duration and tumor phenotype in 972 breast cancer patients. Sleep duration was inversely associated with tumor grade (univariate ), particularly in postmenopausal women (univariate ). This association did not reach statistical significance after adjustments for age, race, body mass index, hormone replacement therapy use, alcohol consumption, smoking, and physical activity in the entire study sample ( ), but it remained statistically significant ( ) among post-menopausal patients. We did not observe a statistically significant association between sleep duration and stage at diagnosis, ER, or HER2 receptor status. These results present a modest association between short duration of sleep and higher grade breast cancer in post-menopausal women. Further work needs to be done to validate these findings. 1. Introduction Breast cancer is the leading cancer in women in the United States and the third leading cause of cancer deaths among women [1]. It was estimated that over 220,000 women will be diagnosed in 2012 with breast cancer, with almost 40,000 women deaths [2]. Women diagnosed with localized breast cancer have a very favorable outcome, with a 99% 5-year survival. However, the survival rate decreases to 84% with regional disease and 23% for women with distant metastases, underscoring the importance of identifying factors associated with the development of more aggressive breast cancers. There is an emerging evidence for the role of sleep deprivation in carcinogenesis, with new research suggesting that disruptions in the circadian rhythm may increase the risk of several types of cancer [3–5], including breast cancer (reviewed in [6]). In the few studies of sleep duration and risk of breast cancer, the association of short sleep duration and the incidence of breast cancer has been mixed, with one study suggesting a decreased risk of breast cancer in women who slept longer [7], two other studies showing an inverse association between sleep duration and risk of breast cancer [8, 9], and a fourth study that did not find evidence of this association [10]. However, much less work has been done to investigate whether short sleep duration prior to the diagnosis is associated with breast cancer phenotype. Markers of more aggressive and advanced breast cancer include stage, determined by the size of the tumor and lymph node status or
Pathophysiology and pathogenesis of circadian rhythm sleep disorders
Akiko Hida, Shingo Kitamura, Kazuo Mishima
Journal of Physiological Anthropology , 2012, DOI: 10.1186/1880-6805-31-7
Abstract: The circadian clock system regulates daily rhythms of physiology and behavior, such as the sleep-wake cycle and hormonal secretion, body temperature and mood [1]. These rhythms are entrained by environmental cues, light-dark (LD) cycles and food intake. In mammals, the master clock in the suprachiasmatic nuclei (SCN) of the hypothalamus incorporates environmental information and coordinates the phase of oscillators in peripheral cells, tissues and organs [2,3]. Light is one of the most potent environmental cues that enable the organisms to adapt to the 24-hour environmental LD cycle. Photic signals are delivered from the eye to the SCN via the retinohypothalamic tract, thereby mediating the entrainment of the circadian clock system [4]. The circadian clock system involves transcription-translation negative feedback loops of multiple clock genes and posttranscriptional modification and degradation of clock proteins [4-6] (Figure 1). The basic helix-loop-helix and Per-Arnt-Sim transcription factors CLOCK and BMAL1 form heterodimers and activate transcription of Period 1 (Per1), Per2, Per3, Cryptochrome 1 (Cry1), Cry2 and retinoid-related orphan receptor α (Rorα), Rorβ, Rorγ, Rev-Erbα and Rev-Erbβ by binding to E-box motifs on their promoter regions. PER and CRY proteins gradually accumulate in the cytoplasm and phosphorylation of PER and CRY occurs with casein kinase Iδ (CKIδ) and CKIε. PER, CRY and CKI proteins form complexes that translocate to the nucleus and interact with CLOCK-BMAL1 heterodimers, thereby inhibiting transcription of the Per, Cry, Ror and Rev-Erb genes. Meanwhile, Bmal1 transcription is regulated positively by retinoid-related orphan receptor (ROR) and negatively by REV-ERB via the ROR element (RORE) motif on the Bmal1 promoter.A two-process model is a major model of sleep regulation. Two components, homeostatic drive and circadian drive, interact with each other and regulate the sleep-wake cycle [7]. The sleep-wake cycle is controlled by sleep hom
Sleep Duration and Sleep Problems in a Representative Sample of German Children and Adolescents  [PDF]
Angelika A. Schlarb, Marco D. Gulewitsch, Victoria Weltzer, Ute Ellert, Paul Enck
Health (Health) , 2015, DOI: 10.4236/health.2015.711154
Abstract: Objective: The main purpose of the present study was to evaluate sleep duration for nighttime sleep from early infancy to late adolescence in a German sample to illustrate the developmental course and age-specific variability of these variables among subjects. Methods: A total of 17,641 subjects from the KiGGS study were evaluated. The questionnaires contained questions about physical health, living circumstances, health behavior and risks, health supply, mental health, health-related quality of life and sleep. KiGGS assessed sleep by using parent questionnaire of children aged 0 to 10 years (n = 9944) and self-reports of adolescents (n = 7697) aged 11 to 17 years. Results: Total sleep duration decreased from 14.28 hours (SD = 2.33) at the ages 0 - 0.5 to 9.50 hours (SD = 0.82) at the ages of 10.5 - 11. Above the age of 11 adolescents report a decrease of sleep at night from 9.41 hours (SD = 1.33) at the age of 11 - 11.5 to 7.42 (SD = 1.73) at the age of 17.5 - 18 years. Unspecified sleep problems were reported of 19.5%, 13.0% of the children had difficulties falling asleep, difficulties sleeping through the night showed 8.8% of the children, whereas 3.0% report both symptoms—difficulties falling asleep and difficulties sleeping through the night. Conclusions: Age-specific variability of sleep duration is reported as well as sleep difficulties from infancy to adolescence. This is important knowledge for the health care professional who deals with sleep problems in pediatric practice.
Association of Duration of Sleep and Cardiovascular and Metabolic Comorbidities in Sleep Apnea Syndrome  [PDF]
Zeynep Zeren Ucar,Ali Kadri Cirak,Serhan Olcay,Hatice Uysal,Ahmet Ugur Demir,R?fat ?zacar
Sleep Disorders , 2012, DOI: 10.1155/2012/316232
Abstract: Background/Aim. Previous population-based studies found association between duration of sleep and cardiovascular and metabolic comorbidities. Our aim was to investigate the association between the duration of sleep and cardiovascular and metabolic comorbidities in OSAS. Patients and Methods. The study enrolled 312 patients, who had polysomnography (PSG) during 2006-2007 and responded to a telephone-administered questionnaire providing information on characteristics of sleep on average 12 months after PSG. Results. Of the patients, 90 were female (28.8%), 173 (58.5) received the diagnosis of OSAS, 150 (45%) had no comorbidities, 122 had hypertension (HT), 44 had diabetes mellitus (DM), and 38 had coronary heart disease (CHD). Mean ± SD of age in years was , , , and for the no comorbidity, HT, DM, and CHD groups, respectively. Reported duration of sleep was not associated with any of the comorbidities in the overall group. In the analysis restricted to OSAS patients, sleep duration ≤6 hours was significantly associated with CHD after the adjustment for age, gender, and other associated factors (OR: 5.8, 95% CI: 1.0–32.6). Conclusions. Confirmation of the association between shorter duration of sleep and CHD will provide prognostic information and help for the management of OSAS. 1. Introduction Sleep loss is a common condition in modern society. Although the health effects of sleep deprivation have been obscure, recent epidemiological studies have revealed relationships between sleep deprivation and hypertension (HT), coronary heart disease (CHD), and diabetes mellitus (DM) [1]. Because sleep deprivation increases sympathetic nervous system activity, this increased activity serves as a common pathophysiology for HT, DM, and CHD. Previous studies showed that sleep duration less than 6 hours or more than 8 hours is associated with increased morbidity and mortality due to cardiovascular diseases in the general population [2, 3]. Obstructive sleep apnea syndrome (OSAS) is a common medical disorder that is growing in prevalence worldwide. It is characterized by recurrent cycles of intermittent hypoxia and there is increasing evidence that intermittent hypoxia plays a role in the development of cardiovascular risk in OSAS patients through the activation of inflammatory pathways. Some excellent review articles have already summarized the effects of OSAS on HT, CHD, and DM [4–6]. The pathogenesis of cardiovascular disease in OSAS is not completely understood but is likely to be multifactorial, involving a diverse range of mechanisms including sympathetic nervous
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