Exploring the Mediating Role of Sleep Deficit-Related Functional Status in Subacute Stroke Survivors.

Background: Understanding post-stroke fatigue (PSF) and its associated factors is crucial for effective therapy and rehabilitation. This study aimed to assess the mediating role of the excessive daytime sleepiness-related functional status (SFS) on the relationship between sleep and the severity of fatigue in subacute stroke survivors. Methods: Subacute stroke survivors (n = 50; male = 38; female = 12), completed a cross-sectional study involving the Pittsburgh sleep quality index (PSQI), the Epworth sleepiness scale (ESS), the insomnia severity index (ISI), the functional outcome of the sleep questionnaire (FOSQ), and the fatigue severity scale (FSS). Results: The SFS mediated the association between the severity of fatigue and sleep problems. The PSQI and FOSQ (b = -0.37, p < 0.001), and the FOSQ and FSS were correlated (b = -0.18, p < 0.05), with a significant indirect effect of the PSQI on the FSS. The ISI correlated with the FOSQ (b = -0.20, p < 0.001), with significant direct (b = 0.15, p < 0.001), as well as indirect, effects of the ISI on the FSS. The ESS correlated with the FOSQ (b = -0.23, p < 0.001), with a significant indirect effect of the ESS on the FSS. Conclusions: In subacute stroke survivors, fatigue and sleep are linked. Increased understanding of sleep-PSF may help in exploring new targets for supplement therapy.

Timing is everything: Circadian rhythms and their role in the control of sleep.

Sleep and the circadian clock are intertwined and have persisted throughout history. The suprachiasmatic nucleus (SCN) orchestrates sleep by controlling circadian (Process C) and homeostatic (Process S) activities. As a "hand" on the endogenous circadian clock, melatonin is critical for sleep regulation. Light serves as a cue for sleep/wake control by activating retino-recipient cells in the SCN and subsequently suppressing melatonin. Clock genes are the molecular timekeepers that keep the 24 h cycle in place. Two main sleep and behavioural disorder diagnostic manuals have now officially recognised the importance of these processes for human health and well-being. The body's ability to respond to daily demands with the least amount of effort is maximised by carefully timing and integrating all components of sleep and waking. In the brain, the organization of timing is essential for optimal brain physiology.

Prevalence of poor sleep quality in the Ethiopian population: a systematic review and meta-analysis.

BACKGROUND: Only a limited amount of data is available from lower-income countries regarding the prevalence of poor quality of sleep. This meta-analysis of the scientific literature was performed to estimate the pooled prevalence of poor sleep quality in the Ethiopian population. METHODS: The study protocol followed was the Preferred Reporting of Items for Systematic Review and meta-analysis (PRISMA) statement. RESULTS: The nine studies which met the inclusion criteria provided data based on a total of 9103 participants who were studied at various health and academic institutions. The incidences of self-reported poor sleep quality ranged from 26 to 66.2%. The pooled estimate of poor sleep quality was 53%.There was a high prevalence of reported poor quality of sleep among younger subjects and among those who were studied in community (noninstitutional) settings. CONCLUSION: The pooled prevalence of poor sleep quality is quite high among Ethiopians.

Understanding the role of sleep and its disturbances in Autism spectrum disorder.

BACKGROUND: Several studies have established a positive relationship between sleep difficulties and symptomatology in ASD children. The rationale for this review is to describe and discuss the sleep difficulties, which are one of the significant complications associated with autism spectrum disorder (ASD). PURPOSE: Many types of sleep disorders have been reported in ASD individuals, but still lack a comprehensive study and in-depth analysis. Despite the contribution of sleep problems to the overall symptoms of ASD, the symptoms of disturbed sleep experienced by many affected patients have only recently started to receive attention from clinicians and family members. MATERIALS AND METHODS: This narrative overview has been prepared based on searching standard research databases with specific keywords; b. Additional search was made using the bibliographies of the retrieved articles; and c. author's collection of relevant peer-reviewed articles. Once selected, manuscripts are then compared and summarized based on the author's perspective. Results are based on a qualitative rather than a quantitative level. RESULTS: This article highlights the role of sleep in the brain and neural development of children and emphasizes that the intensity of sleep problems is associated with an increased occurrence of ASD symptoms. It also suggests the significance of treating sleep problems in ASD individuals. CONCLUSIONS: The review provides broader perspectives and a better understanding of sleep problems in pathophysiology, mechanism, and management with respect to ASD individuals. Finally, the implications for clinical practice and future agendas have also been discussed.

Dimensionality of the Pittsburgh Sleep Quality Index: a systematic review.

BACKGROUND: The Pittsburgh Sleep Quality Index (PSQI) dimensionality is much debated, with the greatest number of reported factor structures. Therefore, this review appraised the methodologies of studies investigating the factor structure of the PSQI. MATERIAL AND METHODS: MEDLINE, PsycInfo, AJOL, BASE, Cochrane Library, Directory of Open Access Journals (Lund University), CINAHL, and Embase were searched systematically to include articles published till 23rd March, 2018. The articles with the objective of factor analysis of the PSQI (20 articles) or with a major section on the same subject (25 articles) were included. There was no limitation about participant characteristics. Descriptive analysis of articles for measures of the suitability of the data for factor analysis, details of the exploratory factor analysis (EFA) and details of the confirmatory factor analysis (CFA) was performed. RESULTS: The analysis used by the majority did not employ the simplest scheme for interpreting the observed data: the parsimony principle. Other shortcomings included under- or non-reporting of sample adequacy measures (11 out of 45 articles), non-use of EFA (20 out of 45 articles), use of EFA without relevant details, non-use of CFA (11 out of 45 articles), and use of CFA without relevant details. Overall, 31 out of 45 articles did not use either EFA or CFA. CONCLUSION: We conclude that the various PSQI factor structures for standard sleep assessment in research and clinical settings may need further validation. TRIAL REGISTRATION: Not applicable because this was a review of existing literature.

Chronobiological theories of mood disorder.

Major depressive disorder (MDD) remains the most prevalent mental disorder and a leading cause of disability, affecting approximately 100 million adults worldwide. The disorder is characterized by a constellation of symptoms affecting mood, anxiety, neurochemical balance, sleep patterns, and circadian and/or seasonal rhythm entrainment. However, the mechanisms underlying the association between chronobiological parameters and depression remain unknown. A PubMed search was conducted to review articles from 1979 to the present, using the following search terms: "chronobiology," "mood," "sleep," and "circadian rhythms." We aimed to synthesize the literature investigating chronobiological theories of mood disorders. Current treatments primarily include tricyclic antidepressants and selective serotonin reuptake inhibitors, which are known to increase extracellular concentrations of monoamine neurotransmitters. However, these antidepressants do not treat the sleep disturbances or circadian and/or seasonal rhythm dysfunctions associated with depressive disorders. Several theories associating sleep and circadian rhythm disturbances with depression have been proposed. Current evidence supports the existence of associations between these, but the direction of causality remains elusive. Given the existence of chronobiological disturbances in depression and evidence regarding their treatment in improving depression, a chronobiological approach, including timely use of light and melatonin agonists, could complement the treatment of MDD.

Are Type 2 Diabetes Mellitus and Depression Part of a Common Clock Genes Network?

In recent years, there has been an increased prevalence of type 2 diabetes mellitus (T2DM) and depression across the world. This growing public health problem has produced an increasing socioeconomic burden to the populations of all affected countries. Despite an awareness by public health officials and medical researchers of the costs associated with these diseases, there still remain many aspects of how they develop that are not understood. In this article, we propose that the circadian clock could be a factor that coordinates both the neurobehavioral and metabolic processes that underlie depression and T2DM. We propose further that this perspective, one which emphasizes the regulatory effects of clock gene activity, may provide insights into how T2DM and depression interact with one another, and may thus open a new pathway for managing and treating these disorders.

Racial/Ethnic and Social Inequities in Sleep Medicine: The Tip of the Iceberg?

PURPOSE: It is known that racial disparities exist in terms of disease prevalence and access to health care. However, the link between race/ethnicity and sleep quality is often under-recognized. RESULTS: Current evidence shows that differences exist between Blacks and Whites in terms of sleep duration, sleep quality, and the likelihood of acquiring a sleep disorder. It has been argued that the adverse effects of ethnicity on sleep quality or duration interact with other social or personal factors (such as employment) and that the effects of these factors are interactive and need to be analyzed simultaneously. There is a growing body of evidence showing that disturbed sleep is a mediator of the effect of environmental stressors on personal health, which is more pronounced in ethnic minorities. CONCLUSIONS: These findings support the notion that perceived discrimination or unfair treatment has significant associations with complaints of sleep disturbance and disturbed objective measures of sleep quality and sleep architecture. Hence, greater efforts are needed to demonstrate how racial/ethnic factors influence different sleep processes.

Association between sleep quality and inflammatory complement components in collegiate males.

BACKGROUND: An accumulating amount of evidence has linked humoral mediators of inflammation with sleep measures. Nevertheless, important details of this association, in particular the role of the complement components in the context of chronic sleep attributes, have remained largely uncharacterized. MATERIALS AND METHODS: Fifty university students (age, 23.3 ± 3.8 years; BMI, 23.7 ± 2.9 kg/m(2)) completed the study. Four dichotomized sleep measures assessed by the Pittsburgh Sleep Quality Index (PSQI) were used in association analysis using binary logistic regression with complement component 3, 4, and complement factor I (CFI). The sleep measures were defined as sleep quality (good sleep/poor sleep; PSQI ≤5/PSQI >5), bedtime (early/late; before 00:00 h/after 0:00 h), sleep duration (short/normal ≤6 h/>6 h), and sleep onset latency (normal/disturbed; 0-1 score/2-3 score on the PSQI component of sleep latency). RESULTS: The complement component 4 was associated with sleep quality (unadjusted, OR = 1.025, p < 0.05; adjusted for age, OR = 1.025, p < 0.05; adjusted for BMI, OR = 1.027, p < 0.05) and sleep duration (unadjusted, OR = 1.041, p < 0.01; adjusted for age, OR = 1.041, p < 0.01; adjusted for BMI, OR = 1.046, p < 0.01). CFI was associated with bedtime (unadjusted, OR = 0.737, p < 0.01; adjusted for age, OR = 0.717, p < 0.01; adjusted for BMI, OR = 0.677, p < 0.01) and with sleep duration (unadjusted, OR = 0.796, p < 0.05; adjusted for age, OR = 0.796, p < 0.05). CONCLUSION: The findings indicate the importance of the role of complement components in the dynamics of sleep. Therefore, sleep should be assessed in conditions where complement components are affected.

Association between visual impairment and sleep duration: analysis of the 2009 National Health Interview Survey (NHIS).

BACKGROUND: Visual impairment (VI) is associated with increased mortality and health factors such as depression and cardiovascular disease. Epidemiologic studies consistently show associations between sleep duration with adverse health outcomes, but these have not systematically considered the influence of VI. The aim of this study was to ascertain the independent association between VI and sleep duration using the National Health Interview Survey (NHIS) data. We also examined whether race/ethnicity influenced these associations independently of sociodemographic and medical characteristics. METHODS: Our analysis was based on the 2009 NHIS, providing valid sleep and vision data for 29,815 participants. The NHIS is a cross-sectional household interview survey utilizing a multistage area probability design. Trained personnel from the US census bureau gathered data during face-to-face interview and obtained socio-demographic, self-reported habitual sleep duration and physician-diagnosed chronic conditions. RESULTS: The mean age of the sample was 48 years and 56% were female. Short sleep and long sleep durations were reported by 49% and 23% of the participants, respectively. Visual impairment was observed in 10%. Multivariate-adjusted logistic regression models showed significant associations between VI and short sleep (OR = 1.6, 95% CI = 1.5-1.9 and long sleep durations (OR = 1.6, 95% CI = 1.3-1.9). These associations persisted in multivariate models stratified by race-ethnic groups. CONCLUSION: Visual impairment was associated with both short and long sleep durations. Analysis of epidemiologic sleep data should consider visual impairment as an important factor likely to influence the amount of sleep experienced habitually.

Dysregulated light/dark cycle impairs sleep and delays the recovery of patients in intensive care units: A call for action for COVID-19 treatment.

Exposure to an adequate light-dark cycle is important for the speedy recovery of hospitalized and institutionalized patients. Light exposure, including natural light, offers several health benefits to both patients and nursing staff. This includes physical (e.g., decreased confusion and disorientation) and mental health benefits (e.g., prevention of depression) and a reduction in the hospital stay. Improved alertness and performance can also be noted among hospital staff. In this commentary, we discuss disrupting factors that include light during the nighttime along with noise and physical procedures on the patient and others. We then address some of the important steps that can be undertaken to restore a more normal environment for patients in the intensive care unit, which can be particularly important for COVID-19 patients.

The Origin and Clinical Relevance of Yoga Nidra.

Yoga nidra, also known as 'yogic sleep', is a simplified form of an ancient tantric relaxation technique. The most general description of the practice is that it combines guided mental imagery with a specific yoga posture called Shavasana (or "corpse pose"). The goal of yoga nidra is to promote a profound state of relaxation, which differs from sleep inasmuch as there is still an awareness of one's surroundings. While several components of the practice have been known since ancient times, it was not until the 1960s that an updated and systematized system of practice was introduced to the public through the writings of Swami Satyananda Saraswati. Unlike other schools of yoga, which emphasize concentration or contemplation, yoga nidra's goal is complete relaxation. As such, its advocates claim that it is suitable for all individuals, from beginners to advanced practitioners of yoga. The calm inner stillness induced by yoga nidra is claimed by practitioners to be an effective stress management tool as well as a means for attaining greater receptivity to personal resolutions. These resolutions can range from the goal of achieving self-transformation, enhancing creativity, or improving one's learning ability. Additionally, yoga nidra is claimed to promote beneficial changes in physiological and mental health. The following narrative review summarizes the basic steps used to achieve the final state of yoga nidra relaxation as well as some recent experimental findings regarding its physiological and psychological effects. Standard research databases were searched for relevant articles. Clinical studies have shown that yoga nidra meditation is associated with positive physiological changes, including improvements in several hematological variables, red blood cell counts, blood glucose levels, and hormonal status. Two neuroimaging studies have shown that yoga nidra produces changes in endogenous dopamine release and cerebral blood flow, a further confirmation that its effects on the CNS are objectively measurable. The practice has also been shown to reduce psychometrically measured indices of mild depression and anxiety, although these benefits were not shown in an experimental study to extend to severe depression or severe anxiety.

Is poor sleep quality associated with a deterioration in postural control?

OBJECTIVE: The primary aim was to investigate whether any association exists between poor sleep quality and deterioration in postural control among university student population. MATERIALS AND METHODS: A case-control study was conducted in which sleep quality of 119 university students from different departments of Jamia Millia Islamia University, New Delhi, India was assessed using Pittsburgh sleep quality index (PSQI) following which the participants postural control, or dynamic balance was measured using the Y balance test (YBT). The participants were divided into two groups (A and B) based on their PSQI cut off scores. The YBT data was then evaluated for the dynamic balance assessment of the participants. RESULTS: The mean age of the participants was 22.23±2.29 out of which 86 were female and 33 were male. The mean BMI of the participants was 21.58±3.66. Group A included 63 participants who had "good" sleep quality (global PSQI score < 5) whereas group B included 56 participants who had "poor" sleep quality (global PSQI score ≥ 5). Group comparisons based on t-test revealed a significant difference (p<0.05) between means of the two groups, with the mean balance of group A being greater than that of group B. Also, chi-square testing showed no significant association between the BMI and dynamic balance scores for the participants (p<0.10). CONCLUSION: The findings of the study conclude that poor sleep quality is associated with a deterioration of postural control in university students. The study also revealed that there was no association between BMI and dynamic balance in this population.

Can sleep profiles predict autistic traits in siblings of children with autism spectrum disorder?

INTRODUCTION: As the prevalence of ASD (autism spectrum disorder) continues to rise, so does the need to evaluate the impact of associated difficulties on both the diagnosed child and the immediate family. OBJECTIVES: The aim of the present study was to assess reports of sleep disturbance or abnormal sleep behaviours (sleep profiles) in the siblings of diagnosed autistic children (referred to throughout this study as high-risk siblings, or HR-sibs) and to determine if these sleep patterns correlated with evidence of disturbed sleep among their siblings who had full symptoms of autistic spectrum disorder. MATERIAL AND METHODS: This case control cross-sectional study investigated 64 autistic children, 80 HR-sibs, and 80 typically developing children. Each study subject was assessed for sleep problems and autistic traits through the use of a sleep-wake diary, a school sleep habit survey, and a childhood autism spectrum test. RESULTS: Children with autism spectrum disorders and their HR-sibs showed no significant differences regarding their sleep profiles. Typically, developing children had more middle insomnia than HR-sibs and had more wake latency. CONCLUSION: Increased risks for sleep problems in children with autism and their HR-sibs emphasized the importance of early screening for sleep problems in children with autism and their siblings.

Depressive Symptoms, Sleep Profiles and Serum Melatonin Levels in a Sample of Breast Cancer Patients.

BACKGROUND: Chronobiological changes have been detected in various physiological functions of patients with breast cancer, suggesting dysregulation in the pineal gland and melatonin secretion. This study aimed to assess and measure serum melatonin levels pre- and postoperatively in patients who had been diagnosed for the first time with breast cancer. METHODS: A sample of first-time breast cancer patients, consisting of 45 women aged 25-65 years, was evaluated and psychometric assessment was completed using the Beck Depression Inventory (BDI), Insomnia Severity Index (White, Weinberg et al) and the Epworth Sleepiness Scale (Cardoso, Spence et al). The Morningness-Eveningness questionnaire (MEQ) was used to assess the chronotype. Serum melatonin levels were measured by radioimmunoassay. RESULTS: Morning and moderately morning chronotypes were prevalent among the sample (25%, 45.8%, respectively). The finding of a mean BDI score of 13.5±11.2 indicated that depressive symptoms were prevalent among the sample. Despite the finding that a mean of the participants apparently had no symptoms of daytime sleepiness (the mean and standard deviations of the ESS were 7.5±4.4), scores on the ISI (a mean of 16.7±SD 7.3) indicated that insomnia symptoms were prevalent in the sample. Melatonin levels showed an inverse relationship with insomnia severity as measured by the ISI and depression severity, as assessed by the BDI. The postoperative melatonin levels were higher than the preoperative levels. Additionally, the psychometric profile differed among various pathological types of breast cancer according to their hormone receptor profile. CONCLUSION: Serum melatonin levels correlated significantly with self-reported sleep quality and psychometric profiles of depression in the present sample of breast cancer patients. The melatonin assay, which is relatively easy to carry out, provided a convenient, objective measure of an important biological correlate of sleep quality and depression. This assay thus represented a confirmatory alternative to the self-report instruments, which may sometimes be unreliable. Future studies should further evaluate the utility of melatonin measures in psychiatric and sleep complaints of breast cancer patients.

Basic chronobiology: what do sleep physicians need to know?

Sleep is an essential physiological process, which profoundly affects a wide range of biological activities. It is now known that sleep supports myriad vital functions in the central nervous system. This includes neural plasticity, learning, memory, cognition and emotional regulation. Additionally, it affects basic processes such as cardiovascular, immunological and metabolic activity. Evidence from multiple lines of research has thus shown that good quality of sleep is essential for both survival and optimal functioning of life. Considerable evidence also supports the conclusion that even minimal dysfunctions in circadian regulation can significantly disrupt sleep and broadly affect body physiology. As a consequence, it is now appreciated that the therapy of sleep disorders is more complex than was once thought. At present, several clinical disciplines have recognized the significance of the biological clock in health and illness, and are incorporating this knowledge into treatment programs. Recent decades have seen the emergence of chronotherapies, i.e., treatment strategies that are aimed at producing adjustments in the circadian clock. The final objective of these approaches is to affect basic cellular and physiological processes, which in turn may be at the root of disorders such as physiological aging, immune functioning, metabolic activity, and psychiatric disturbance. It is suggested that the integration of chronobiological perspectives into many mainstream medical disciplines would be of significant benefit, both for the reduction of the prevalence of diseases and their treatment. This review considers the physiology of sleep and the importance of timekeeping mechanisms in the regulation of overall health.

Prevalence and Predictors of Neurocognitive Impairment in Ethiopian Population Living with HIV.

BACKGROUND: Modern antiretroviral therapy has extended the life expectancies of people living with HIV; however, the prevention and treatment of their associated neurocognitive decline have remained a challenge. Consequently, it is desirable to investigate the prevalence and predictors of neurocognitive impairment to help in targeted screening and disease prevention. MATERIALS AND METHODS: Two hundred and forty-four people living with HIV were interviewed in a study using a cross-sectional design and the International HIV Dementia Scale (IHDS). Additionally, the sociodemographic, clinical, and psychosocial characteristics of the patients were recorded. Chi-square and binary logistic regression analysis were used to determine the level of significance among the independent risk factors and probable neurocognitive impairment. RESULTS: The point prevalence of neurocognitive impairment was found to be 39.3%. Participants' characteristics of being older than 40 years (AOR= 2.81 (95% CI; 1.11-7.15)), having a history of recreational drug use (AOR= 13.67 (95% CI; 6.42-29.13)), and being non-compliant with prescribed medications (AOR= 2.99 (95% CI; 1.01-8.87)) were independent risk factors for neurocognitive impairment. CONCLUSION: The identification of predictors, in the Ethiopian people living with HIV, may help in the targeted screening of vulnerable groups during cART follow-up visits. This may greatly help in strategizing and implementation of the prevention program, more so, because (i) HIV-associated neurocognitive impairment is an asymptomatic condition for considerable durations, and (ii) clinical trials on neurocognitive impairment therapies have been unsuccessful.

Insomnia Symptoms and Their Association with Anxiety and Poor Sleep Hygiene Practices Among Ethiopian University Students.

OBJECTIVE: There is a paucity of research evidence available regarding the impact of anxiety and sleep hygiene on insomnia and related sleep complaints among collegiate students in lower-income countries. The purpose of this study was to investigate if insomnia and insomnia-related sleep complaints are associated with anxiety, age, and sleep hygiene practices among a sample of university students in Ethiopia. DESIGN MEASURES SETTING AND PARTICIPANTS: The participants were young adults (n=525; mean age 21.5 ± 3.0 years; mean BMI of 20.7 ± 2.7kg/m2). Young collegiate adults at Mizan-Tepi University in southwestern Ethiopia were randomly selected to participate in this cross-sectional study. The measures included the Leeds Sleep Evaluation Questionnaire-Mizan (LSEQ-M), the Generalized Anxiety Disorder-7 Scale (GAD-7), and the Sleep Hygiene Index (SHI). Descriptive statistics, binary logistic regression, and multiple linear regressions were used. RESULTS: Insomnia was associated with young age group (≤25 years) (odds ratio (OR) = 2.20, 95% confidence interval (CI) 1.04-4.66), higher GAD-7 (anxiety) (OR = 1.05, 95% CI 1.0-1.10) and SHI (poor sleep hygiene) (OR = 1.15, 95% CI 1.05-1.26) scores. All four insomnia-related sleep complaints were associated with increasing GAD-7 scores, as well as higher SHI scores (p<0.001). CONCLUSION: Insomnia was associated with younger age group (≤25 years), higher anxiety level, and poor sleep hygiene. Four major sleep complaints in insomnia, ie, sleep onset problems, poor sleep quality, awakening problems, and daytime disturbances, were all associated with higher anxiety levels and poor sleep hygiene.

Clarifying the role of sleep in depression: A narrative review.

It has been established that 4.4 to 20% of the general population suffers from a major depressive disorder (MDD), which is frequently associated with a dysregulation of normal sleep-wake mechanisms. Disturbances of circadian rhythms are a cardinal feature of psychiatric dysfunctions, including MDD, which tends to indicate that biological clocks may play a role in their pathophysiology. Thus, episodes of depression and mania or hypomania can arise as a consequence of the disruption of zeitgebers (time cues). In addition, the habit of sleeping at a time that is out of phase with the body's other biological rhythms is a common finding in depressed patients. In this review, we have covered a vast area, emerging from human and animal studies, which supports the link between sleep and depression. In doing so, this paper covers a broad range of distinct mechanisms that may underlie the link between sleep and depression. This review further highlights the mechanisms that may underlie such link (e.g. circadian rhythm alterations, melatonin, and neuroinflammatory dysregulation), as well as evidence for a link between sleep and depression (e.g. objective findings of sleep during depressive episodes, effects of pharmacotherapy, chronotherapy, comorbidity of obstructive sleep apnea and depression), are presented.