Comorbid Sleep Disturbances in Neurologic Disorders

The Reciprocal Relationship between Sleep and Epilepsy

The relationship between sleep and epilepsy is bidirectional. Certain epilepsy syndromes predominantly or exclusively manifest during sleep, with seizures frequently originating from non-rapid eye movement (NREM) sleep. Interictal epileptiform discharges observed on electroencephalograms are most likely to be activated during the deep NREM sleep stage known as N3. Conversely, epileptiform discharges, anti-seizure medications (ASMs), as well as other anti-seizure therapies can exert detrimental effects on sleep architecture. Moreover, the co-occurrence of sleep disorders has the potential to exacerbate seizure control. Understating the relationship between sleep and epilepsy is crucial for healthcare providers. Addressing and managing sleep-related problems in individuals with epilepsy can potentially contribute to improved seizure control and overall well-being. At the same time, improving seizure control can improve sleep quality and quantity, thus further improving the health of individuals with epilepsy.

How Does Chronobiology Contribute to the Development of Diseases in Later Life

An increasingly older population is one of the major social and medical challenges we currently face. Between 2010 and 2050, it is estimated that the proportion of adults over 65 years of age will double from 8% to 16% of the global population. A major concern associated with aging is the changes in health that can lead to various diseases such as cancer and neurogenerative diseases, which are major burdens on individuals and societies. Thus, it is imperative to better understand changes in sleep and circadian rhythms that accompany aging to improve the health of an older population and target diseases associated with aging. Circadian rhythms play a role in most physiological processes and can contribute to age-related diseases. Interestingly, there is a relationship between circadian rhythms and aging. For example, many older adults have a shift in chronotype, which is an individual's natural inclination to sleep certain times of the day. As adults age, most people tend to go to sleep earlier while also waking up earlier. Numerous studies also suggest that disrupted circadian rhythms may be indicative of developing age-related diseases, like neurodegenerative disorders and cancer. Better understanding the relationship between circadian rhythms and aging may allow us to improve current treatments or develop novel ones that target diseases commonly associated with aging.

Alzheimer's Disease, Sleep Disordered Breathing, and Microglia: Puzzling out a Common Link

Sleep Disordered Breathing (SDB) and Alzheimer's Disease (AD) are strongly associated clinically, but it is unknown if they are mechanistically associated. Here, we review data covering both the cellular and molecular responses in SDB and AD with an emphasis on the overlapping neuroimmune responses in both diseases. We extensively discuss the use of animal models of both diseases and their relative utilities in modeling human disease. Data presented here from mice exposed to intermittent hypoxia indicate that microglia become more activated following exposure to hypoxia. This also supports the idea that intermittent hypoxia can activate the neuroimmune system in a manner like that seen in AD. Finally, we highlight similarities in the cellular and neuroimmune responses between SDB and AD and propose that these similarities may lead to a pathological synergy between SDB and AD.

An Association Rule Analysis of the Acupressure Effect on Sleep Quality

BACKGROUND

Sleep is recognized as an all-important physiological process, which also contributes to maintaining several bodily functions and systems. According to the Pittsburgh Sleep Quality Index (PSQI), also known as the most widely used tool in the field of subjective assessment of self-perceived sleep quality, a combination of acupoints could be more effective than single acupoint treatment in improving sleep quality.

METHODS

The present study was based on the extracted eligible studies rooted in a previous meta-analysis that worked on the basis of association rule mining and examined the potential kernel acupoint combinations for improving sleep quality.

RESULTS

Depending on the Apriori algorithm, we summarized 26 acupoints as binary data from the 32 eligible studies based on a previous meta-analysis and analyzed them. The top 10 most frequently selected acupoints were HT7, SP6, PC6, KI1, GV20, EM5, EX-HN3, EX-HN16, KI3, and MA-TF1. Furthermore, as deduced from 21 association rules, the primary relevant rules in the combination of acupoints are (EX-HN3, EX-HN16)=>(GV20) and (HT7, KI1)=>(PC6).

CONCLUSIONS

In order to use acupuncture to improve sleep quality, integrating (EX-HN3, EX-HN16, GV20) with (HT7, KI1, PC6) acupoints could be deemed as the kernel acupoint combination.

Sleep Disorder and Long-Term Mortality Among Sepsis Survivors: A Nationwide Cohort Study in South Korea

BACKGROUND

We aimed to investigate the association of sleep disorder diagnosis among sepsis survivors with 5-year all-cause mortality.

METHODS

Using the National Health Insurance Service (NHIS) database of South Korea, we included adult sepsis survivors who were primarily diagnosed with sepsis between 2011 and 2014 and survived for more than one year after diagnosis. The diagnosis of sleep disorders was evaluated using the International Classification of Diseases, 10th revision codes of G47* in the NHIS database.

RESULTS

In total, 45,826 survivors of sepsis were included in this analysis. Among the sepsis survivors, 2935 (6.4%) were newly diagnosed with a sleep disorder within 1 year after the date of sepsis diagnosis, while 7938 (17.3%) were already diagnosed with sleep disorder before the date of sepsis diagnosis. In the multivariable Cox regression, the risk of 5-year all-cause mortality in the pre- and post-sepsis sleep disorder groups was 1.19-fold (hazard ratio: 1.19, 95% confidence interval: 1.14-1.24; P<0.001) and 1.79-fold (hazard ratio: 1.79, 95% confidence interval: 1.70-1.89; P<0.001) higher than that of the control group.

CONCLUSION

A 6.4% of sepsis survivors in South Korea were newly diagnosed with a sleep disorder within 1 year of sepsis diagnosis. Although both pre- and post-sepsis sleep disorders were associated with a higher 5-year all-cause mortality rate, the risk of the 5-year all-cause mortality in the post-sepsis sleep disorder group was higher than that in the pre-sepsis sleep disorder group.

A review of the mechanisms underlying selected comorbidities in Alzheimer's disease

Alzheimer's disease (AD) is a progressive neurodegenerative disorder of the central nervous system (CNS) leading to mental deterioration and devastation, and eventually a fatal outcome. AD affects mostly the elderly. AD is frequently accompanied by hypercholesterolemia, hypertension, atherosclerosis, and diabetes mellitus, and these are significant risk factors of AD. Other conditions triggered by the progression of AD include psychosis, sleep disorders, epilepsy, and depression. One important comorbidity is Down’s syndrome, which directly contributes to the severity and rapid progression of AD. The development of new therapeutic strategies for AD includes the repurposing of drugs currently used for the treatment of comorbidities. A better understanding of the influence of comorbidities on the pathogenesis of AD, and the medications used in its treatment, might allow better control of disease progression, and more effective pharmacotherapy.

Sleep health, diseases, and pain syndromes: findings from an electronic health record biobank

STUDY OBJECTIVES

Implementation of electronic health record biobanks has facilitated linkage between clinical and questionnaire data and enabled assessments of relationships between sleep health and diseases in phenome-wide association studies (PheWAS). In the Mass General Brigham Biobank, a large health system-based study, we aimed to systematically catalog associations between time in bed, sleep timing, and weekly variability with clinical phenotypes derived from ICD-9/10 codes.

METHODS

Self-reported habitual bed and wake times were used to derive variables: short (<7 hours) and long (≥9 hours) time in bed, sleep midpoint, social jetlag, and sleep debt. Logistic regression and Cox proportional hazards models were used to test cross-sectional and prospective associations, respectively, adjusted for age, gender, race/ethnicity, and employment status and further adjusted for body mass index.

RESULTS

In cross-sectional analysis (n = 34,651), sleep variable associations were most notable for circulatory system, mental disorders, and endocrine/metabolic phenotypes. We observed the strongest associations for short time in bed with obesity, for long time in bed and sleep midpoint with major depressive disorder, for social jetlag with hypercholesterolemia, and for sleep debt with acne. In prospective analysis (n = 24,065), we observed short time in bed associations with higher incidence of acute pain and later sleep midpoint and higher sleep debt and social jetlag associations with higher incidence of major depressive disorder.

CONCLUSIONS

Our analysis reinforced that sleep health is a multidimensional construct, corroborated robust known findings from traditional cohort studies, and supported the application of PheWAS as a promising tool for advancing sleep research. Considering the exploratory nature of PheWAS, careful interrogation of novel findings is imperative.

Insomnia disorder: clinical and research challenges for the 21st century

BACKGROUND AND PURPOSE

Insomnia is a common and debilitating disorder that is frequently associated with important consequences for physical health and well-being.

METHODS

An international expert group considered the current state of knowledge based on the most relevant publications in the previous 5 years, discussed the current challenges in the field of insomnia and identified future priorities.

RESULTS

The association of trajectories of insomnia with subsequent quality of life, health and mortality should be investigated in large populations. Prospective health economics studies by separating the costs driven specifically by insomnia and costs attributable to its long-term effects are needed. Ignoring the heterogeneity of insomnia patients leads to inadequate diagnosis and inefficient treatment. Individualized interventions should be promoted. More data are needed on both the impact of sleep on overnight effects, such as emotion regulation, and the potential compensatory effort to counteract diurnal impairments. Another gap is the definition of neurocognitive deficits in insomnia patients compared to normal subjects after chronic sleep loss. There are also a number of key gaps related to insomnia treatment. Expert guidelines indicate cognitive-behavioural therapy for insomnia as first-line treatment. They neglect, however, the reality of major healthcare providers. The role of combined therapy, cognitive-behavioural therapy for insomnia plus pharmacological treatment, should be evaluated more extensively.

CONCLUSION

Whilst insomnia disorder might affect large proportions of the population, there are a number of significant gaps in the epidemiological/clinical/research studies carried out to date. In particular, the identification of different insomnia phenotypes could allow more cost-effective and efficient therapies.

Effect of repetitive transcranial magnetic stimulation (rTMS) for insomnia: a protocol for a systematic review

INTRODUCTION

Repetitive transcranial magnetic stimulation (rTMS), a non-invasive brain stimulation approach, might be a promising technique in the management of insomnia. A systematic review of the available literature on this topic is warranted. The systematic review described in this protocol aims to investigate the efficacy of rTMS as a physical therapy in patients with insomnia.

METHODS AND ANALYSIS

This protocol was developed in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols. We will retrieve relevant literatures across the following electronic bibliographic databases: CENTRAL, PubMed, EMBASE, PsycINFO, CINAHL, PEDro, CBM, CNKI, WANFANG and VIP. A manual search of the reference lists of all relevant articles will be performed for any additional studies. We will include randomised controlled trials published in English and Chinese examining efficacy of rTMS on patients with insomnia. Two reviewers will independently complete the article selection, data extraction and rating. PEDro scale will be used to assess the methodological quality of the included studies. Narrative and quantitative synthesis will be done accordingly.

ETHICS AND DISSEMINATION

Ethical approval will not be required for this review. The results of this review will be disseminated in a peer-review journal.

PROSPERO REGISTRATION NUMBER

CRD42018115033.

Polysomnography Findings and Sleep Disorders in Children With Alternating Hemiplegia of Childhood

STUDY OBJECTIVES

Patients with alternating hemiplegia of childhood (AHC) experience bouts of hemiplegia and other paroxysmal spells that resolve during sleep. Patients often have multiple comorbidities that could negatively affect sleep, yet sleep quality and sleep pathology in AHC are not well characterized. This study aimed to report sleep data from both polysomnography (PSG) and clinical evaluations in children with AHC.

METHODS

We analyzed nocturnal PSG and clinical sleep evaluation results of a cohort of 22 consecutive pediatric patients with AHC who were seen in our AHC multidisciplinary clinic and who underwent evaluations according to our comprehensive AHC clinical pathway. This pathway includes, regardless of presenting symptoms, baseline PSG and evaluation by a board-certified pediatric sleep specialist.

RESULTS

Out of 22 patients, 20 had at least one type of sleep problem. Six had obstructive sleep apnea as documented on polysomnogram, of whom two had no prior report of sleep-disordered breathing symptoms. Patients had abnormal mean overall apnea-hypopnea index of 5.8 (range 0-38.7) events/h and an abnormal mean arousal index of 15.0 (range 4.8-46.6) events/h. Based on sleep history, 16 patients had difficulty falling asleep, staying asleep, or both; 9 had behavioral insomnia of childhood; and 2 had delayed sleep-wake phase syndrome.

CONCLUSIONS

Sleep dysfunction is common among children with AHC. Physicians should routinely screen for sleep pathology, with a low threshold to obtain a nocturnal PSG.

Sex differences in sleep apnea and comorbid neurodegenerative diseases

Sleep apnea is a disorder, which increasingly affects people worldwide. Whether the associated hypoxic events during sleep are central or obstructive in origin, the end result is excessive daytime sleepiness and an increased risk for several comorbidities, such as cardiovascular and neurodegenerative disorders. Sleep apnea is diagnosed more frequently in men than women, suggesting a role of sex hormones in the pathology of the disease. Furthermore, there are sex differences in the development and progression of comorbid diseases associated with sleep apnea. Therefore, treatment of sleep apnea may be clinically relevant for prevention of subsequent sex-specific comorbid disorders. While the impact sleep apnea has on cardiovascular events has been the subject of many research studies, the role of sleep apnea in neurodegeneration is less established. Here we review known risk factors for sleep apnea and the implications of the observed sex differences in this disease. We also summarize the evidence and mechanisms for how sleep apnea may contribute to the onset of neurodegenerative disorders, such as Alzheimer's disease and Parkinson's disease.