Current Sleep Medicine Reports最新文献

Purpose of review: Little is known about how incretins interact with sleep and circadian factors, both of which influence metabolic outcomes. We review evidence that sleep, circadian rhythms, and their disturbances impact incretin secretion and discuss clinical applications for GLP-1/GIP-RA drugs in sleep medicine and areas for future research.

Recent findings: GLP-1 secretion exhibits a circadian rhythm which may be disrupted by high-fat diet, meal timing, and gut dysbiosis. Insufficient sleep may alter the timing of postprandial GLP-1 release, and the circadian rhythm of GLP-1 secretion is blunted in patients with metabolic conditions such as obesity or diabetes. Lastly, the FDA has approved the use of tirzepatide (a GLP-1/GIP-RA drug) for treating obstructive sleep apnea.

Summary: Evidence suggests that sleep and circadian rhythms impact the incretin system, although findings are somewhat mixed due to the variety of methods employed. In light of the growing interest in new clinical applications for incretin therapies, more research is needed to fully understand the relationship between sleep, circadian rhythms, and incretin secretion.

Purpose of review: Sleep and circadian biology is fundamental to human health. Following the advancement in sleep medicine and availability of multi-omics technology, this review outlines the current knowledge regarding genetic basis and multi-omics research on circadian rhythm and the two most prevalent sleep disorders, obstructive sleep apnea (OSA) and insomnia.

Recent findings: Genome wide association analyses identified variants across circadian genes and genes pertinent to inflammation, obesity and neuronal function associated with OSA and insomnia. Multi-omics integration has led to novel breakthroughs in identifying systemic biomarkers and elucidating cascades, and causal associations underpinning these complex traits.

Summary: Multi-omics studies in sleep and circadian rhythm possess great potential in unveiling molecular mechanisms behind circadian rhythm and sleep, thereby advancing personalized medicine in the long term. Nevertheless, researchers should remain mindful of existing challenges in genetic and multi-omics sleep research, including data harmonization and existing racial and ethnic disparities in data collection and availability, limiting research generalizability.

Purpose of the review: The purpose of this review is to provide an overview of potential mechanisms mediating the bi-directional relationship between sleep and neurodegenerative diseases such as Alzheimer's disease. We provide updates on previously proposed mechanisms and identify new mechanisms particularly concerning how sleep disturbances affect memory-related neural circuits.

Recent findings: In this review, we focus on the multiple mechanisms that potentially mediate the relationship between sleep and Alzheimer's disease. We present updates for previously hypothesized mechanisms such as sleep-related changes in production/release and clearance of amyloid-β and tau proteins as well as more recently proposed mechanisms relating to tau phosphorylation, the orexin system, astrocytes, and microglia. We also highlight how disruptions in sleep EEG oscillations that underlie memory-related neural circuits, such as slow wave activity, theta bursts, sleep spindles, and gamma ripples, change in Alzheimer's disease.

Summary: Disturbed sleep increases Alzheimer's disease risk via multiple potential mechanisms that suggest multiple targets to test approved and effective treatments of sleep disorders to prevent or delay Alzheimer's disease.

Purpose of review: Age-related changes in the circadian timing system may play a role in the development of disorders in older age. We review key aspects of the human circadian system that change with aging, discuss recent evidence of how changes in sleep and circadian rhythms manifest in neurodegenerative diseases, and summarize research on new therapies.

Recent findings: Several mechanisms have been proposed to underlie age-related changes in sleep and circadian rhythmicity. These mechanisms include changes in the suprachiasmatic nucleus, melatonin production, and light sensitivity as well as impaired glymphatic drainage, buildup of amyloid-beta, hypoxia from sleep-disordered breathing, and increased levels of orexin. While light-based therapies and lifestyle interventions have been under investigation for years, newer interventions include treatment with orexin antagonists and gamma stimulation to improve sleep and circadian rhythmicity.

Summary: Despite growing interest, our understanding of how sleep and circadian rhythms contribute to the development of age-related neurodegenerative diseases is still limited. More research is needed to understand the bidirectional relationship between circadian rhythms, sleep, and neurodegenerative diseases to develop targeted interventions.

Purpose of review: Daytime napping, a brief sleep episode during the day, has mixed health effects. This review explores the relationship between daytime napping frequency and health outcomes by synthesizing results from published Mendelian randomization (MR) studies, which help mitigate confounding and reverse causality commonly observed in traditional epidemiological research.

Recent findings: A total of 35 studies spanning seven major disease categories were identified, with cardiovascular, neurological, and metabolic outcomes being the most frequently investigated in MR. Of the 89 tested outcomes, 36% of studies suggested increased disease risk with more frequent daytime napping, 54% reported no associations, and 10% suggested decreased disease risk with more frequent daytime napping. Not all MR findings align with existing epidemiological research.

Summary: The current evidence from MR does not provide a definitive conclusion regarding the health effects of daytime napping. Future research should consider additional dimensions of napping beyond frequency and integrate both genetic and non-genetic approaches in diverse populations.

Purpose of review: Obstructive sleep apnea (OSA) affects at least 1 billion people worldwide, and its increasing prevalence is alarming considering an association to comorbidities such as cardiovascular disease (CVD) and to demonstrated health disparities. This raises concerns regarding the current diagnostic standards, which are also impacted by disparities. The current review was aimed at identifying limitations in the apnea-hypopnea index (AHI), the primary clinical indicator of OSA severity, and analyzing recent alternatives. In addition, the association between OSA and CVD was discussed, and, considering the role of intermittent hypoxia, solutions were proposed for improving OSA diagnosis.

Recent findings: Based on a review of current literature, alternative metrics to the AHI such as the hypoxia burden, sleep apnea-specific pulse rate, and oxygen desaturation rate were shown to be correlated with indicators of CVD in OSA patients. A recent mathematical study also presents the possibility of a model-based metric to eliminate existing bias in diagnostics and provide a more accurate quantification of tissue hypoxia.

Summary: The analyzed studies give incentive to look beyond current clinical standards in OSA. Through this review, we motivate the use of mathematical modeling as a future avenue to improve OSA diagnosis with a hypoxia-based approach.

Purpose of review: Despite advancements in basic circadian research, development of new diagnostic and treatment strategies for circadian rhythm sleep-wake disorders (CRSWDs) has been slow. Here, we review the most recent innovations in human circadian assessment and emerging new therapies for CRSWDs.

Recent findings: Researchers have improved existing circadian assessment methods to overcome logistical barriers and developed novel circadian assessment methods. New treatments for CRSWDs involve pharmacological and behavioral treatments that modulate circadian phase, amplitude, and/or robustness of the central circadian clock.

Summary: Commercialization of these emerging tools will require overcoming barriers, such as additional testing to confirm the underlying pathology and mechanism of action of potential treatments. Clinicians and scientists are also called to survey adjacent fields and adopt existing diagnostic tools that may offer diagnostic clarity in CRSWDs. Lastly, we must continue to advocate for medical insurance coverage of current and future tools and technologies to improve patient care.

Purpose of review: Sleep disturbances are common in individuals with gastrointestinal (GI) disorders. The connection between sleep and GI symptoms is bidirectional and influenced by shared biopsychosocial mechanisms and cognitive-behavioral factors, including alterations in the stress response. Treating sleep disturbances can effectively manage coexisting symptoms. This review explores current research on sleep treatments for GI conditions, emphasizing mind-body interventions that target stress.

Recent findings: Both pharmacological and non-pharmacological approaches (e.g., cognitive behavioral therapy for insomnia) benefit patients with sleep disturbance and concomitant GI symptoms; however, they have limitations. Other approaches, including mind-body interventions, may improve sleep quality, reduce GI symptoms, and enhance quality of life.

Summary: Mind-body interventions can complement other evidence-based approaches for patients with co-morbid sleep disturbance and GI symptoms. However, more rigorous research is warranted to fully understand their benefit. As research evolves, healthcare professionals can guide patients on how to best integrate these approaches into their care.

Purpose of review: Sleep is dynamic across the lifespan, influenced by brain maturation, neurophysiology, hormones, and cognitive processes. Sleep behaviors influenced by physiological and external factors can also impact sleep health. As sleep plays a mechanistic role in health across the lifespan, understanding when and how to intervene to benefit health is essential.

Recent findings: Recent research has advanced our understanding of sleep across three domains: patterns, neurophysiology, and behaviors. Highlights include (1) Early childhood nap cessation is thought to relate to medial temporal lobe network maturation and underlie long-term hippocampal-dependent memory development. (2) Chronotype misalignment is a key factor in sleep deficits and social jetlag. (3) Older adult daytime sleep has complex effects on health, at times beneficial while others, potentially maladaptive. (4) Longitudinal sleep oscillation trajectories are starting to be investigated and indicate neurophysiology could be interpreted as indicative of brain maturation in development. (5) In adults, sleep quality and macrostructure trajectories show high variability, emphasizing distinctive traits in shaping sleep and its lifespan trajectories. (6) Neighborhood and socioeconomic factors influence sleep health across all ages. (7) In older adults, associations between loneliness and poor sleep are being unpacked.

Summary: This recent research, while comprehensively describing our current understanding of sleep trajectories across the lifespan, emphasizes the need to expand current approaches to longitudinal measurement studies that cross age-spans. Expanding will enhance our ability to mechanistically determine the temporal and causal relations between the multiple dimensions of sleep (i.e., patterns, behaviors, and physiology) and outcomes in sleep health.

Purpose of review: Racial disparities in sleep health as well as the diagnosis and treatment of sleep disorders have emerged as a key driver of cardiovascular outcomes. Obstructive sleep apnea (OSA), is characterized by repeated airway obstructions during sleep and is associated with an increased risk of cardiovascular disease. While racial and ethnic minorities have disproportionately high OSA prevalence rates, diagnosis rates remain low. One explanation behind this phenomenon are structural environmental and lifestyle barriers that prevent access to OSA care. Additionally, there remains significantly limited understanding of OSA and its causes and symptoms within communities.

Recent findings: In general, minorities have poorer sleep health due to systemic and environmental racism, which also causes an increased in conditions such as obesity that increases OSA risk. Disparities also persist within various types of OSA treatment. The most common form of treatment, continuous positive airway pressure (CPAP) has lower adherence among African Americans, as well as those living in areas with low socioeconomic status (SES), primarily minorities. There have been a small number of studies that have shown some initial success of educational campaigns about OSA within minority communities in increasing screenings and diagnoses. Peer based education has been an effective technique, and there is a need for such programs to be expanded.

Summary: Disparities persist, with minority groups having worse sleep health and lower rates of adherence to OSA treatment. Some grassroots, peer-led educational campaigns show promise in increasing adherence. In light of these disparities, there remains a need for the field of sleep medicine to continue addressing the systemic barriers that hinder the timely evaluation and treatment in racial minorities.