Sleep, insomnia, and depression

Minds and Brains, Sleep and Psychiatry

Objective

This article offers a philosophical thesis for psychiatric disorders that rests upon some simple truths about the mind and brain. Specifically, it asks whether the dual aspect monism—that emerges from sleep research and theoretical neurobiology—can be applied to pathophysiology and psychopathology in psychiatry.

Methods

Our starting point is that the mind and brain are emergent aspects of the same (neuronal) dynamics; namely, the brain–mind. Our endpoint is that synaptic dysconnection syndromes inherit the same dual aspect; namely, aberrant inference or belief updating on the one hand, and a failure of neuromodulatory synaptic gain control on the other. We start with some basic considerations from sleep research that integrate the phenomenology of dreaming with the neurophysiology of sleep.

Results

We then leverage this treatment by treating the brain as an organ of inference. Our particular focus is on the role of precision (i.e., the representation of uncertainty) in belief updating and the accompanying synaptic mechanisms.

Conclusions

Finally, we suggest a dual aspect approach—based upon belief updating (i.e., mind processes) and its neurophysiological implementation (i.e., brain processes)—has a wide explanatory compass for psychiatry and various movement disorders. This approach identifies the kind of pathophysiology that underwrites psychopathology—and points to certain psychotherapeutic and psychopharmacological targets, which may stand in mechanistic relation to each other.

The ‘mind’ emerges from Bayesian belief updating in the ‘brain’

Psychopathology can be read as aberrant belief updating.

Aberrant belief updating follows from any neuromodulatory synaptopathy

Treating insomnia in Swiss primary care practices: A survey study based on case vignettes

Guidelines recommend cognitive behavioural therapy for insomnia (CBT-I) as first-line treatment for chronic insomnia, but it is not clear how many primary care physicians (PCPs) in Switzerland prescribe this treatment. We created a survey that asked PCPs how they would treat chronic insomnia and how much they knew about CBT-I. The survey included two case vignettes that described patients with chronic insomnia, one with and one without comorbid depression. PCPs also answered general questions about treating chronic insomnia and about CBT-I and CBT-I providers. Of the 820 Swiss PCPs we invited, 395 (48%) completed the survey (mean age 54 years; 70% male); 87% of PCPs prescribed sleep hygiene and 65% phytopharmaceuticals for the patient who had only chronic insomnia; 95% prescribed antidepressants for the patient who had comorbid depression. In each case, 20% of PCPs prescribed benzodiazepines or benzodiazepine receptor agonists, 8% prescribed CBT-I, 68% said they knew little about CBT-I, and 78% did not know a CBT-I provider. In the clinical case vignettes, most PCPs treated chronic insomnia with phytopharmaceuticals and sleep hygiene despite their lack of efficacy, but PCPs rarely prescribed CBT-I, felt they knew little about it, and usually knew no CBT-I providers. PCPs need more information about the benefits of CBT-I and local CBT-I providers and dedicated initiatives to implement CBT-I in order to reduce the number of patients who are prescribed ineffective or potentially harmful medications.

Treadmill exercise ameliorates chronic REM sleep deprivation-induced anxiety-like behavior and cognitive impairment in C57BL/6J mice

Various sleep disorders have deleterious effects on mental and cognitive performance. Exercise, as an alternative therapeutic strategy, exerts beneficial impacts on human health. In the present study, we aimed to evaluate the effects of 4 weeks treadmill exercise (4W-TE) on anxiety-like behavior and cognitive performance in mice exposed to 2 months REM sleep deprivation (2M-SD) (20 h per day). Behavioral performance of mice in elevated plus maze test (EPM), open field test (OFT), Y maze test (YM) and Morris water maze test (MWM) was recorded and analyzed 28 h after the last day of sleep deprivation. After behavioral tests, various neurotransmitters including norepinephrine (NE), dopamine (DA), serotonin (5-HT) and γ-aminobutyric acid (GABA) in mouse hippocampus were quantified using high performance liquid chromatography. The hippocampal levels of insulin-like growth factor-1 (IGF-1) and brain derived neurotrophic factor (BDNF) were further detected using ELISA. Behavioral data indicated that 2M-SD exposure induced anxiety-like behaviors and cognitive impairment, as evidenced by the decreased open-arm entries in EPM, reduced central area travels in OFT, declined spontaneous alteration in YM and prolonged escaping latency in MWM. In addition, 2M-SD exposure increased NE and DA, decreased 5-HT and GABA, and reduced IGF-1 and BDNF levels in mouse hippocampus. Interestingly, all these behavioral, neurochemical and neurobiological changes can be ameliorated by 4W-TE training. In summary, these findings confirm the beneficial impacts of exercise on health and provide further experimental evidence for future application of exercise as an alternative therapy against the mental and cognitive problems in patients with sleep disorders.

Sleep disturbances among medical workers during the outbreak of COVID-2019

Background

The outbreak of Corona Virus Disease-2019 (COVID-19) has posed unprecedented pressure and threats to healthcare workers in Wuhan and the entire country.

Aims

To assess the effect of the COVID-19 outbreak on the sleep quality of healthcare workers in a children’s healthcare centre in Wuhan.

Methods

A cross-sectional, anonymized, self-reported questionnaire survey was conducted at the Children’s Healthcare Centre of Renmin Hospital, Wuhan University, Wuhan, China. The questionnaire consisted of three parts, including socio-demographic characteristics and COVID-19 epidemic-related factors, the Pittsburgh sleep quality index (PSQI), and Zung’s self-rating anxiety scale (SAS) and self-rating depression scale (SDS).

Results

In total, 47 out of 123 (38%) participants with PSQI scores > 7 were identified as having sleep disturbance. A logistic regression analysis showed that sleep disturbance was independently associated with being an only child (adjusted odds ratio (OR) and 95% confidence interval (CI) 3.40 (1.21–9.57), P < 0.05), exposure to COVID-19 patients (adjusted OR and 95% CI 2.97 (1.08–8.18), P < 0.05) and depression (adjusted OR and 95% CI 2.83 (1.10–7.27), P < 0.05).

Conclusions

We observed that, during the outbreak of COVID-19, sleep disturbance was highly prevalent among paediatric healthcare workers, and sleep disturbance was independently associated with being an only child, exposure to COVID-19 patients and depression. Therefore, more mental health services are required for front-line paediatric healthcare workers in Wuhan.

Sleep disturbance and psychiatric disorders

Signs of mental ill health that cut across psychiatric diagnostic categories at high rates are typically viewed as non-specific occurrences, downgraded in importance and disregarded. However, problems not associated with particular diagnoses should be expected if there is shared causation across mental health conditions. If dynamic networks of interacting symptoms are the reality of mental health presentations, then particularly disruptive and highly connected problems should be especially common. The non-specific occurrence might be highly consequential. One non-specific occurrence that is often overlooked is patients' chronic difficulty in getting good sleep. In this Review, we consider whether disrupted sleep might be a contributory causal factor in the occurrence of major types of mental health disorders. It is argued that insomnia and other mental health conditions not only share common causes but also show a bidirectional relationship, with typically the strongest pathway being disrupted sleep as a causal factor in the occurrence of other psychiatric problems. Treating insomnia lessens other mental health problems. Intervening on sleep at an early stage might be a preventive strategy for the onset of clinical disorders. Our recommendations are that insomnia is assessed routinely in the occurrence of mental health disorders; that sleep disturbance is treated in services as a problem in its own right, yet also recognised as a pathway to reduce other mental health difficulties; and that access to evidence-based treatment for sleep difficulties is expanded in mental health services.

The Role of Emotion Regulation Difficulties in the Relation Between Insomnia and Depressive Symptoms

BACKGROUND

Emotion regulation (ER) difficulties have been reported to be more severe in individuals with insomnia symptoms compared with controls, which in turn might explain the experience of depressive symptoms in these individuals. To our knowledge, no study has directly tested this hypothesis; therefore, we aimed to examine the indirect association between possible insomnia disorder and depressive symptoms through ER difficulties.

METHOD

One hundred and seven individuals with possible insomnia disorder and 268 controls (based on a cutoff score on the Sleep Condition Indicator) completed measures of ER difficulties and depressive symptoms.

RESULTS

As expected, individuals with possible insomnia disorder showed more severe depressive symptoms and ER difficulties compared with controls. Moreover, there was a significant indirect association between possible insomnia disorder and depressive symptoms through overall ER difficulties.

CONCLUSION

ER difficulties were more severe in individuals with possible insomnia disorder and were further associated with more severe depressive symptoms. We speculate that by adding interventions aimed to develop ER abilities, Cognitive Behavioral Therapy for Insomnia (CBT-I) could become a more effective intervention for individuals with insomnia symptoms and associated emotional difficulties.

LIMITATIONS

We used cross-sectional measures in our models of indirect associations.

Dietary Approaches to Stop Hypertension (DASH) Score and Its Association with Sleep Quality in a National Survey of Middle-Aged and Older Men and Women

Complex processes appear to link sleep duration and quality with dietary patterns. Numerous studies show healthful benefits of the Dietary Approaches to Stop Hypertension (DASH) diet, but few have examined its association with sleep duration or quality. The current study tested cross-sectional associations of DASH diet quality score with sleep quality among adults. Analyses of participants were from the 2005–2008 wave of the National Health and Nutrition Examination Surveys (n = 3941 adults ≥30 years of age, complete data). We performed sex- and age group-stratified multiple OLS regression analyses with DASH total score and components as main predictors and sleep quality as main outcomes, adjusting sequentially for socio-demographic, behavioral and health-related factors. Sex and age differences in associations of DASH with sleep quality, adjusting for covariates, were also examined by incorporating two-way interaction terms between sex/age and the DASH score in each unstratified model. We found that the DASH diet score was inversely related to poor sleep-related daytime dysfunction adjusted by age, sex, demographic and socio-economic factors. Some sex-specific associations were detected between DASH diet component scores and sleep quality. Notably, the potassium DASH component was inversely associated with Factor 1 (“sleepiness and sleep disturbance”) among women. The fiber DASH component was associated with better sleep quality and inversely related to Factor 2 (“sleep-related daytime dysfunction”) in younger subjects. This study indicates health benefits of the DASH diet for sleep duration and quality. Future longitudinal studies and randomized placebo-controlled trials are required to ascertain protective effects.

Comparison between acupuncture and cognitive behavioral therapy for primary insomnia: A protocol for systematic review and network meta-analysis

BACKGROUND

Primary insomnia (PI) is a common disease affecting human health. As the side effects of drug therapy were revealed, people began to seek more safe and effective non-drug therapies. Cognitive behavioral therapy for insomnia (CBT-I) and acupuncture are 2 commonly used non-drug therapies. However, there are few comparative studies on the efficacy of these 2 therapies. Therefore, this study aims to compare the efficacy and safety of the 2 therapies through network meta-analysis.

METHODS

We will search the following electronic bibliographic databases: PubMed, EMBASE, The Cochrane Library, Web of Science, China National Knowledge Infrastructure, Chinese Biomedical Literature Database, Chongqing VIP database, and Wanfang database. Randomized controlled trials in which the intervention was acupuncture or CBT, and in which the control group was any of the above, western medicine or blank control, would be included. The primary outcome will be the changes of the Pittsburgh Sleep Quality Index, and the additional outcomes will include the changes in Insomnia Severity Index, quality of life, clinical effective rate and adverse events. Two independent authors will screen the literature in the above database, extract data and cross-check. Heterogeneity and inconsistencies are detected before using a network meta-analysis method based on frequency analysis. The risk of bias will be assessed in accordance with the Cochrane risk of bias tool, and the strength of the recommendations will be assessed by the Grading of Recommendations Assessment, Development and Evaluation.

ETHICS AND DISSEMINATION

This network meta-analysis will provide a reference for clinicians and PI patients to choose a more appropriate non-drug regimen among multiple kinds of acupuncture or CBT-I therapies. This review does not require ethical approval and will be reported in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

PROSPERO CRD42020155327.

The relationship between sleep efficiency and clinical symptoms is mediated by brain function in major depressive disorder

BACKGROUND

Sleep disturbance is a common and key symptom that affects most of patients with major depressive disorder (MDD). However, neural substrates underlying sleep disturbance and their clinical relevance in depression remain unclear.

METHODS

Ninety-six MDD patients underwent resting-state functional MRI. Fractional amplitude of low-frequency fluctuation (fALFF) and resting-state functional connectivity (rsFC) were used to measure brain function. Overnight polysomnography was performed to objectively measure sleep efficiency (SE), which was used to classify patients into normal sleep efficiency (NSE) and low sleep efficiency (LSE) groups. Between-group differences in fALFF and rsFC were examined using two-sample t-tests. Moreover, correlation and mediation analyses were conducted to test for potential associations between SE, brain functional changes, and clinical variables.

RESULTS

LSE group showed decreased fALFF in right cuneus, thalamus, and middle temporal gyrus compared to NSE group. MDD patients with low SE also exhibited lower rsFC of right cuneus to right lateral temporal cortex, which was associated with more severe depression and anxiety symptoms. More importantly, mediation analyses revealed that the relationships between SE and severity of depression and anxiety symptoms were significantly mediated by the altered rsFC. In addition, these low SE-related brain functional alterations were not affected by antidepressant medication and were independent of structural changes.

LIMITATIONS

The lack of healthy controls because of "first-night effect".

CONCLUSION

These findings not only may expand existing knowledge about neuropathology of sleep disturbance in depression, but also may inform real-world clinical practice by improving depression and anxiety symptoms through sleep regulation.

Brain Structural and Functional Alterations Specific to Low Sleep Efficiency in Major Depressive Disorder

Background

Sleep disturbance is common in patients with major depressive disorder (MDD), but the exploration of its neural underpinnings is limited by subjective sleep measurement and single-modality neuroimaging analyses.

Methods

Ninety six patients with MDD underwent polysomnography examinations and multi-modal magnetic resonance imaging (MRI) scans. According to sleep efficiency, patients were subdivided into well-matched normal sleep efficiency (NSE, N = 42; 14 men; aged 43 ± 10 years) and low sleep efficiency (LSE, N = 54; 23 men; aged 45 ± 12 years) groups. Inter-group differences in brain structure and function were examined by applying voxel-based morphometry (VBM), regional homogeneity (ReHo) and functional connectivity strength (FCS), and tract-based spatial statistics (TBSS) approaches to structural, functional, and diffusion MRI data, respectively.

Results

There was no significant difference in gray matter volume (GMV) between the NSE and LSE groups. Compared with the NSE group, the LSE group showed increased axial diffusivity in the left superior and posterior corona radiata, and left posterior limb and retrolenticular part of internal capsule. In addition, the LSE group exhibited decreased ReHo in the bilateral lingual gyri and right postcentral gyrus yet increased FCS in the left angular gyrus relative to the NSE group. Moreover, validation analyses revealed that these results remained after adjusting for the medication effect.

Conclusion

Our data indicate that preserved gray matter morphology, impaired white matter integrity, and decreased local synchronization degree yet increased FCS are specific to low SE in MDD patients. These findings of disassociation between structural and functional alterations might provide insights into the neural mechanisms of sleep disturbance in depression.

The Circadian Clock as an Essential Molecular Link Between Host Physiology and Microorganisms

Advances in high-throughput sequencing technologies in the past decade has led to a tremendous growth in knowledge about the role played by microorganisms on our body health. Trillions of microbes live in close symbiosis with their host, and have impacts on various aspects of host physiology as well as predisposition to disease. This is a consequence of the direct interaction between host cells and microbes or their signaling molecules, such as metabolites, which can reach and exert their effects in distal tissues. Among the essential factors modulating the human body's ecosystem of symbionts, the circadian clock might be one of the key regulators. The endogenous clock is a highly conserved timekeeper able to align organismal physiology to the daily cycle, thus maximizing survival and fitness. Circadian rhythms coordinate whole-body biological processes synchronizing cellular biochemical reactions, tissue function and finally controlling systemic homeostasis. Intriguingly, growing body of evidence has demonstrated that the host circadian cycle governs the structure of the gut microbiota community and its diurnal rhythmicity, whereas the microbes contribute to maintenance of clock function. In this review, we will give an overview of the multisystem aspects of microbiome-host interactions in the context of circadian rhythmicity. In particular, the effect of the interaction clock-microbial communities on immune system function and metabolic homeostasis will be discussed. Finally, the possible implication of daily rhythm on the gut-microbiome-brain axis will be analyzed, focusing on the reciprocal effects of clock disruption and microbiota alterations on brain function and behavior.

Insomnia in the Italian Population During Covid-19 Outbreak: A Snapshot on One Major Risk Factor for Depression and Anxiety

Objectives: One of the largest clusters of Covid-19 infections was observed in Italy. The population was forced to home confinement, exposing individuals to increased risk for insomnia, which is, in turn, associated with depression and anxiety. Through a cross-sectional online survey targeting all Italian adult population (≥18 yrs), insomnia prevalence and its interactions with relevant factors were investigated. Methods: The survey was distributed from 1st April to 4th May 2020. We collected information on insomnia severity, depression, anxiety, sleep hygiene behaviors, dysfunctional beliefs about sleep, circadian preference, emotion regulation, cognitive flexibility, perceived stress, health habits, self-report of mental disorders, and variables related to individual difference in life changes due to the pandemic's outbreak. Results: The final sample comprised 1,989 persons (38.4 ± 12.8 yrs). Prevalence of clinical insomnia was 18.6%. Results from multivariable linear regression showed that insomnia severity was associated with poor sleep hygiene behaviors [β = 0.11, 95% CI (0.07-0.14)]; dysfunctional beliefs about sleep [β = 0.09, 95% CI (0.08-0.11)]; self-reported mental disorder [β = 2.51, 95% CI (1.8-3.1)]; anxiety [β = 0.33, 95% CI (0.25-0.42)]; and depression [β = 0.24, 95% CI (0.16-0.32)] symptoms. Conclusion: An alarming high prevalence of clinical insomnia was observed. Results suggest that clinical attention should be devoted to problems of insomnia in the Italian population with respect to both prevention and treatment.

Sleep Health and Serious Psychological Distress: A Nationally Representative Study of the United States among White, Black, and Hispanic/Latinx Adults

PURPOSE

Prior studies investigating the relationship between sleep and serious psychological distress (SPD) have lacked racial/ethnic diversity and generalizability. We investigated associations between sleep and SPD among a large, nationally representative, and racially/ethnically diverse sample of US adults.

METHODS

We pooled cross-sectional data from the 2004 to 2017 National Health Interview Survey. Participants self-reported sleep duration and sleep disturbances (eg, trouble falling and staying asleep). SPD was defined as a Kessler Psychological Distress Scale (K6) score ≥13. Adjusting for sociodemographic, health behavior, and clinical characteristics, we used Poisson regression with robust variance to estimate prevalence ratios (PRs) and 95% confidence intervals (CIs) of SPD for each sleep characteristic, overall and by race/ethnicity.

RESULTS

Among 316,840 participants, the mean age ± standard error was 46.9 ± 0.1 years, 52% were women, 75% were non-Hispanic (NH)-White, 16% NH-Black, and 9% Hispanic/Latinx. The prevalence of SPD was 3.4% for NH-Whites, 4.1% for NH-Blacks, and 4.5% for Hispanics/Latinxs. Participants with <7 hours versus 7-9 hours of sleep duration were more likely to have SPD, and the magnitude of the association was strongest among NH-Black participants (PR_NH-Blacks=3.50 [95% CI: 2.97-4.13], PR _{Hispanics/Latinx}=2.95 [2.42-3.61], and PR_NH-Whites=2.66 [2.44-2.89]). Positive associations between sleep disturbances and SPD were generally stronger among NH-Black and Hispanic/Latinx compared to NH-White adults.

CONCLUSION

Poor sleep health was positively associated with SPD, and the magnitude of the association was generally stronger among racial/ethnic minorities. Future investigations should prospectively focus on the determinants and health consequences of SPD attributable to objectively measured sleep across racial/ethnic groups.