Sleep Abnormalities in Different Clinical Stages of Psychosis: A Systematic Review and Meta-analysis

Actigraphy-derived circadian rhythms, sleep-wake patterns, and physical activity across clinical stages and pathophysiological subgroups in young people presenting for mental health care

Staging models for youth mental health aim to locate clinical presentations on a spectrum from at-risk states to persistent disorder and predict future illness trajectories. Our previous publications on trans-diagnostic staging proposed three pathophysiological subgroups of major mood or psychotic disorders in youth ('hyperarousal-anxious depression', 'circadian-bipolar spectrum', 'neurodevelopmental-psychosis'). This study aims to investigate differences in objective measures of 24hr sleep-wake patterns, circadian rhythms, and physical activity across clinical stages and pathophysiological subgroups. Actigraphy data (median: 13 days) was collected from 497 youth presenting for mental health care (21.6 ± 4.7 years, 37% male) and 88 controls (24.1 ± 3.8 years, 44% male). Actigraphy estimates were compared across groups using analysis of covariance adjusting for age and sex. Compared with controls or earlier clinical stages, later clinical stages were significantly associated with longer sleep duration(η2 = 0.04), later sleep midpoint(η2 = 0.02), lower sleep regularity(η2 = 0.02), lower relative amplitude of the rest-activity cycle(η2 = 0.05), higher interdaily stability(η2 = 0.03), lower total activity(η2 = 0.08) and less moderate-vigorous physical activity(η2 = 0.06). Compared to controls, the 'circadian-bipolar spectrum' subgroup had later sleep midpoint(η2 = 0.02), and higher interdaily stability(η2 = 0.03); the 'neurodevelopmental-psychosis' subgroup had longer sleep duration(η2 = 0.02), and lower total activity(η2 = 0.03); and the 'hyperarousal-anxious depression' subtype had later sleep midpoint(η2 = 0.02), and lower sleep regularity(η2 = 0.02). The findings suggest differences in sleep-wake and rest-activity patterns according to clinical stage and proposed illness trajectory subtypes. The cross-sectional associations of sleep regularity and physical activity with clinical stage highlight a need for longitudinal explorations of how sleep-wake patterns and circadian rhythms interact with treatment factors and progression of both mental and physical illness.

Treatment of idiopathic hypersomnia with modafinil in an individual at clinical high risk for psychosis: A case report

Background

Recent studies have shown that sleep disturbances are frequent at different stages of psychosis, including clinical high risk for psychosis (CHR-P). However, the comorbidity of hypersomnia with CHR-P and its treatment have rarely been reported or discussed.

Case Presentation

A 16-year-old female diagnosed with major depressive disorder and CHR-P experienced worsening excessive daytime sleepiness (EDS), including falling sleep in class. Polysomnography and multiple sleep latency tests confirmed the diagnosis of idiopathic hypersomnia (IH), and treatment with modafinil (100 mg/day) was initiated. EDS improved after increasing the modafinil dose to 200 mg/day. No side effects or exacerbations of psychotic symptoms were observed. EDS recurred after she entered university and was treated with 300 mg/day of modafinil without side effects or transition to psychosis.

Conclusion

This case demonstrates modafinil's efficacy and safety in treating IH in individuals with CHR-P. However, whether modafinil use increases the risk of transition to psychosis remains unclear. Further research is required on modafinil as a treatment for hypersomnia in individuals with CHR-P.

Are sleep disturbances a risk factor for suicidal behavior in the first episode of psychosis? Evidence from a systematic review

Sleep disturbances are common in individuals with first-episode psychosis (FEP) and have been identified as potential contributors to an increased risk of suicidal behavior. This systematic review aims to synthesize the existing evidence on the association between sleep disturbances and suicidal behavior in individuals experiencing FEP, a critical period for early intervention. In accordance with the guidelines established by PRISMA, this systematic review was duly registered in PROSPERO (CRD42024598203) prior to its initiation. A comprehensive search was conducted across databases including PubMed, Web of Science, EMBASE, and PsycINFO, encompassing studies from their inception through February 2025. The review specifically included observational studies that investigated the association between sleep disturbances and suicidal behaviors, which include suicidal ideation, attempts, or completed suicides, among individuals with FEP. The inclusion criteria required that all studies featured adult participants aged 18 years and older, employed validated measures for both sleep disturbances and suicidality, and concentrated on populations with FEP. Reviews, case reports, and studies not published in English were systematically excluded. The selection of studies, extraction of data, and assessment of quality were conducted independently by two reviewers. Seven studies met the inclusion criteria, with sample sizes ranging from 118 to 688 participants. The findings indicate that sleep disturbances, especially insomnia, are significantly linked to an increased risk of suicidal ideation and behavior in individuals with FEP. The strength of these associations varied among the studies, with some reporting moderate to strong effect sizes. However, there was noted methodological heterogeneity, including variations in sleep assessment tools. This systematic review highlights sleep disturbances as a key modifiable risk factor for suicidal behavior in individuals with FEP. Future research should prioritize longitudinal designs and standardized sleep assessments to better characterize this relationship and guide targeted interventions.

The Interplay Between the Sleep Slow Oscillation and Cerebrospinal Fluid: New Vistas for Insomnia Research

Insomnia disorder affects about 10% of the global population, representing a major health concern. Despite the availability of evidence-based treatments, the neurobiological mechanisms underpinning this disorder remain poorly understood. Recently, the investigation of the less than 1 Hz oscillations (commonly termed slow oscillations), a hallmark of slow wave sleep, has gained increased interest in research on insomnia. In this context, an intriguing perspective arises from the association between slow oscillations and metabolic waste clearance, an impaired process in individuals suffering from insomnia disorder. Indeed, the exploration of the relationships between cerebrospinal fluid dynamics and glymphatic system functions, which relate to brain metabolic clearance, and sleep slow oscillations may represent a promising avenue for future research in this field. This narrative review examines current knowledge about the intricate interplay among these mechanisms and their implications for insomnia disorder. Particular attention is given to the role of sleep slow oscillations in the clearance of metabolic waste during sleep, their coupling with cerebrospinal fluid oscillations, and the regulatory mechanisms underlying glymphatic function. The review emphasises the relevance of investigating sleep slow oscillations-related mechanisms in insomnia, intending to provide novel insights into the neurophysiological underpinnings of the disorder and contribute to more accurate diagnostic approaches. Furthermore, a deeper understanding of these mechanisms could pave the way for the development of innovative or adjunctive therapeutic strategies targeting sleep slow oscillations-related alterations in insomnia disorder.

Beyond Medication: The Dual Benefits of Physical Activity on Psychosis and Sleep Quality Among Male Patients with Schizophrenia

While antipsychotic medications remain the primary treatment for schizophrenia, they often have limitations in addressing all symptoms and can lead to adverse side effects, prompting researchers to explore complementary approaches such as physical activity to enhance overall patient outcomes. This study investigates the effectiveness of physical activity on psychosis and sleep quality in patients with schizophrenia. This quasi-experimental study involved 70 male inpatients with schizophrenia, divided into an activity group (structured physical activity program) and a control group (standard care). The intervention group showed significant improvements across multiple symptom domains (positive and depression-anxiety) with large effect sizes (η2 ranging from 0.553 to 0.705) compared to the control group. These improvements, including reductions in grandiosity, emotional withdrawal, and anxiety, were maintained at the 3-month follow-up. The study group also exhibited significant improvements in several aspects of sleep quality, including subjective sleep quality (p < 0.001, η2 = 0.612), sleep duration (p < 0.001, η2 = 0.877), and sleep disturbances (p < 0.001, η2 = 0.623). The physical activity program demonstrated significant improvements in sleep quality and various symptoms of schizophrenia, notably hallucinations and unusual thought content. Although the changes in negative symptoms were not statistically significant between groups, the overall findings suggest that physical activity can play a beneficial role in symptom management and enhance sleep quality for patients with schizophrenia.

The Relationship Between Insomnia and Depressive Symptoms in a Sample of Patients With Schizophrenia: Do Psychotic Symptoms Play a Mediating Role?

INTRODUCTION

Depressive symptoms, bidirectionally associated with insomnia, are common comorbidity among patients with schizophrenia. The current literature lacks conclusive evidence about the mediating role of either positive or negative symptoms in the relationship between insomnia and depressive symptoms.

AIM/QUESTION

This study aimed to examine the mediating role of psychotic symptoms on the relationship between insomnia and depression in a sample of patients with schizophrenia.

METHODS

A cross-sectional, mediational design was used in this cross-sectional study, using a convenience sampling method to recruit 279 patients with schizophrenia.

RESULTS

Insomnia total score (β $$ \beta $$ = 0.351, p < 0.001), work status (β $$ \beta $$ = 3.053, p < 0.001), living arrangement (β $$ \beta $$ = -2.071, p = 0.019), number of previous suicide attempts (β $$ \beta $$ = 1.087, p < 0.001) and medication adherence (β $$ \beta $$ = -1.456, p = 0.031) explained 41.9% of the variability in depression total score (F = 41.14, p < 0.001). Negative psychotic symptoms positively (partially) mediated the relationship between insomnia and depression (p < 0.001).

DISCUSSION

The indirect effect for the negative psychotic symptom total score was significant and positive. This finding implies that, on average, higher insomnia total scores increase negative psychotic symptom total scores, which then increase depression scores.

IMPLICATIONS FOR PRACTICE

The study highlights the significance of early detection and management of insomnia by integrating sleep assessments into standard mental health care to mitigate the negative impact of insomnia on both psychotic and depressive symptoms. Furthermore, this proactive approach may help mental health nurses improve patients' long-term outcomes by addressing these comorbidities before they escalate.

Effects of Benzodiazepine Exposure on Real-World Clinical Outcomes in Individuals at Clinical High Risk for Psychosis

BACKGROUND AND HYPOTHESIS

Animal models indicate GABAergic dysfunction in the development of psychosis, and that benzodiazepine (BDZ) exposure can prevent the emergence of psychosis-relevant phenotypes. However, whether BDZ exposure influences real-world clinical outcomes in individuals at clinical high risk for psychosis (CHR-P) is unknown.

STUDY DESIGN

This observational cohort study used electronic health record data from CHR-P individuals to investigate whether BDZ exposure (including hypnotics, eg, zopiclone) reduces the risk of developing psychosis and adverse clinical outcomes. Cox proportional-hazards models were employed in both the whole-unmatched sample, and a propensity score matched (PSM) subsample.

STUDY RESULTS

567 CHR-P individuals (306 male, mean[±SD] age = 22.3[±4.9] years) were included after data cleaning. The BDZ-exposed (n = 105) and BDZ-unexposed (n = 462) groups differed on several demographic and clinical characteristics, including psychotic symptom severity. In the whole-unmatched sample, BDZ exposure was associated with increased risk of transition to psychosis (HR = 1.61; 95% CI: 1.03-2.52; P = .037), psychiatric hospital admission (HR = 1.93; 95% CI: 1.13-3.29; P = .017), home visit (HR = 1.64; 95% CI: 1.18-2.28; P = .004), and Accident and Emergency department attendance (HR = 1.88; 95% CI: 1.31-2.72; P < .001). However, after controlling for confounding-by-indication through PSM, BDZ exposure did not modulate the risk of any outcomes (all P > .05). In an analysis restricted to antipsychotic-naïve individuals, BDZ exposure reduced the risk of transition to psychosis numerically, although this was not statistically significant (HR = 0.59; 95% CI: 0.32-1.08; P = .089).

CONCLUSIONS

BDZ exposure in CHR-P individuals was not associated with a reduction in the risk of psychosis transition or adverse clinical outcomes. Results in the whole-unmatched sample suggest BDZ prescription may be more likely in CHR-P individuals with higher symptom severity.

Sleep and circadian difficulties in schizophrenia: presentations, understanding, and treatment

It is common in mental health care to ask about people's days but comparatively rare to ask about their nights. Most patients diagnosed with schizophrenia struggle at nighttime. The next-day effects can include a worsening of psychotic experiences, affective disturbances, and inactivity, which in turn affect the next night's sleep. Objective and subjective cognitive abilities may be affected too. Patients commonly experience a mix of sleep difficulties in a night and across a week. These difficulties include trouble falling asleep, staying asleep, or sleeping at all; nightmares and other awakenings; poor-quality sleep; oversleeping; tiredness; sleeping at the wrong times; and problems establishing a regular sleep pattern. The patient group is also more vulnerable to obstructive sleep apnea and restless legs syndrome. We describe in this article how the complex presentation of non-respiratory sleep difficulties arises from variation across five factors: timing, mental state, need for sleep, self-care, and environment. We set out 10 illustrative patterns of such difficulties experienced by patients with non-affective psychosis. These sleep problems are eminently treatable with intensive psychological therapy delivered over approximately eight sessions. We describe key techniques and their typical order of implementation by presentation. Sleep problems are an important issue for patients. Giving them the therapeutic attention patients often desire brings both real clinical benefits and improves views of services. Treatment is also very likely to lessen psychotic experiences and mood disturbances while improving daytime functioning and quality of life. Tackling sleep difficulties can be a route toward the successful treatment of psychosis.

Multimodal evidence of mediodorsal thalamus-prefrontal circuit dysfunctions in clinical high-risk for psychosis: findings from a combined 7T fMRI, MRSI and sleep Hd-EEG study

Deficits in mediodorsal thalamus-dorsolateral prefrontal cortex (MDT-DLPFC) resting-state functional magnetic resonance imaging (rs-fMRI) connectivity and prefrontal sleep spindles have been reported in chronic and early course schizophrenia. However, the presence of these alterations in clinical high-risk for psychosis (CHR), alongside their relationships with underlying neurotransmission and cognitive function, remains to be established. Thirty-one CHR and thirty-two HC underwent: 1) 7 T rs-fMRI; 2) 7 T magnetic resonance spectroscopy imaging (MRSI); and 3) sleep electroencephalography (EEG). Rs-fMRI connectivity was analyzed by seeding the whole thalamus (WT) and seven thalamic subsections. Spindle duration was computed across all EEG channels. GABA/creatine (Cr) and glutamate/Cr were calculated in DLPFC and MDT. Relative to HC, CHR showed WT-DLPFC hypoconnectivity (p-FDR = 0.001), especially involving MDT-DLPFC (p-FDR < 0.001) and reduced prefrontal spindle duration (t-stat = -2.64, p = 0.010), while no differences were found for MRSI neuro-metabolites. We then performed clustering analysis using rs-fMRI connectivity and spindle duration to identify CHR and HC subgroups and predict their working memory (WM) performance. A cluster with intact rs-fMRI and spindle duration included mostly HC (83.33% purity), while a cluster with both measures altered involved almost entirely CHR (91.66% purity) and showed worse WM performances. We also examined MRSI metabolites' contribution to spindles and rs-fMRI connectivity with a within-group multivariable regression analysis. In HC, but not in CHR, MDT glutamate/Cr negatively predicted spindle duration and positively predicted MDT-DLPFC connectivity. Combined, these findings indicate that a multimodal neuroimaging approach can identify distinct thalamocortical dysfunctions in CHR individuals, thus informing future research aimed at developing personalized interventions in these individuals.

A spectrum of altered non-rapid eye movement sleep in schizophrenia

Multiple facets of sleep neurophysiology, including electroencephalography (EEG) metrics such as non-rapid eye movement (NREM) spindles and slow oscillations, are altered in individuals with schizophrenia (SCZ). However, beyond group-level analyses, the extent to which NREM deficits vary among patients is unclear, as are their relationships to other sources of heterogeneity including clinical factors, aging, cognitive profiles, and medication regimens. Using newly collected high-density sleep EEG data on 103 individuals with SCZ and 68 controls, we first sought to replicate our previously reported group-level differences between patients and controls (original N = 130) during the N2 stage. Then in the combined sample (N = 301 including 175 patients), we characterized patient-to-patient variability. We replicated all group-level mean differences and confirmed the high accuracy of our predictive model (area under the receiver operating characteristic curve [AUC] = 0.93 for diagnosis). Compared to controls, patients showed significantly increased between-individual variability across many (26%) sleep metrics. Although multiple clinical and cognitive factors were associated with NREM metrics, collectively they did not account for much of the general increase in patient-to-patient variability. The medication regimen was a greater contributor to variability. Some sleep metrics including fast spindle density showed exaggerated age-related effects in SCZ, and patients exhibited older predicted biological ages based on the sleep EEG; further, among patients, certain medications exacerbated these effects, in particular olanzapine. Collectively, our results point to a spectrum of N2 sleep deficits among SCZ patients that can be measured objectively and at scale, with relevance to both the etiological heterogeneity of SCZ as well as potential iatrogenic effects of antipsychotic medication.

Digital sleep phenotype and wrist actigraphy in individuals at clinical high risk for psychosis and people with schizophrenia spectrum disorders: a systematic review and meta-analysis

AIM

To identify sleep abnormalities in individuals at clinical high risk for psychosis (CHR-P) or with schizophrenia spectrum disorders (SSDs) compared with healthy controls (HCs) using wrist actigraphy, and to assess potential differences in the direction of effect with self-reported assessments of sleep.

METHODS

We conducted a systematic review of observational studies, with the search last updated on 29 April 2024. Primary outcome was total sleep time (TST), with secondary outcomes including time in bed (TIB), sleep latency, sleep efficiency, wake after sleep onset, nighttime awakenings and self-reported sleep quality. Random-effects pairwise meta-analyses were used to summarise the effects of each outcome.

RESULTS

Nineteen studies were included, with 18 contributing to the meta-analyses (202 CHR-P, 584 SSD, 582 HC). TST results were inconclusive for CHR-P (MD -4.88 min (95% CI -20.57 to 10.81)), while SSD participants showed an increase in TST compared with HC (MD 106.13 min (86.02 to 124.24)). Factors such as antipsychotic medications (pseudo-R²=88.14%), age (38.89%) and gender (26.29%) partially explained the heterogeneity between subgroups. Additionally, CHR-P individuals exhibited reduced sleep efficiency (MD -2.04% (-3.55 to 0.53)), whereas SSD participants had increased TIB (MD 121.58 min (88.16 to 155.00)) and sleep latency (MD 13.05 min (2.11 to 24.00)). The risk-of-bias assessment ranged from some concerns to high risk.

CONCLUSIONS

Our analyses identified sleep abnormalities in CHR-P and SSD compared with placebo. However, observed heterogeneity and potential biases across studies may limit the interpretability of findings. These limitations underscore the need for standardised guidelines and more precise participant stratification.

Sleep deficiencies and suicidal ideation across the psychosis continuum

Objective

Sleep deficiency, a broad term that encompasses sleep disorder symptoms and other aspects of disturbed sleep, is an established risk factor for suicide. Although several studies have examined the relationship between sleep, suicidal ideation, and suicide attempts among individuals with psychotic disorders, few studies have focused on the early stages of illness. The current study addressed this gap in the literature by examining the relationship between sleep deficiencies, recent suicidal ideation, and lifetime suicidal behavior across the psychosis continuum.

Method

A retrospective chart review was used to obtain relevant data for individuals at clinical high-risk for psychosis (CHR-P), individuals with first-episode psychosis (FEP), and individuals with longstanding illness.

Results

Results indicate that sleep deficiencies are prevalent across all stages of illness, though individuals at CHR-P have significantly higher rates of sleep deficiency than individuals with FEP and longstanding psychosis. Additionally, there was a strong relationship between sleep deficiencies and suicidal ideation across the entire sample.

Conclusions

Further research is needed to clarify the specific nature of these sleep deficiencies and to elucidate the mechanisms by which sleep deficiencies might increase risk for suicide in this population.

Sleep oscillations and their relations with sleep-dependent memory consolidation in early course psychosis and first-degree relatives

Sleep spindles mediate sleep-dependent memory consolidation, particularly when coupled to neocortical slow oscillations (SOs). Schizophrenia is characterized by a deficit in sleep spindles that correlates with reduced overnight memory consolidation. Here, we examined sleep spindle activity, SO-spindle coupling, and both motor procedural and verbal declarative memory consolidation in early course, minimally medicated psychosis patients and non-psychotic first-degree relatives. Using a four-night experimental procedure, we observed significant deficits in spindle density and amplitude in patients relative to controls that were driven by individuals with schizophrenia. Schizophrenia patients also showed reduced sleep-dependent consolidation of motor procedural memory, which correlated with lower spindle density. Contrary to expectations, there were no group differences in the consolidation of declarative memory on a word pairs task. Nor did the relatives of patients differ in spindle activity or memory consolidation compared with controls, however increased consistency in the timing of SO-spindle coupling were seen in both patients and relatives. Our results extend prior work by demonstrating correlated deficits in sleep spindles and sleep-dependent motor procedural memory consolidation in early course, minimally medicated patients with schizophrenia, but not in first-degree relatives. This is consistent with other work in suggesting that impaired sleep-dependent memory consolidation has some specificity for schizophrenia and is a core feature rather than reflecting the effects of medication or chronicity.

A transdiagnostic prodrome for severe mental disorders: an electronic health record study

Effective prevention of severe mental disorders (SMD), including non-psychotic unipolar mood disorders (UMD), non-psychotic bipolar mood disorders (BMD), and psychotic disorders (PSY), rely on accurate knowledge of the duration, first presentation, time course and transdiagnosticity of their prodromal stages. Here we present a retrospective, real-world, cohort study using electronic health records, adhering to RECORD guidelines. Natural language processing algorithms were used to extract monthly occurrences of 65 prodromal features (symptoms and substance use), grouped into eight prodromal clusters. The duration, first presentation, and transdiagnosticity of the prodrome were compared between SMD groups with one-way ANOVA, Cohen's f and d. The time course (mean occurrences) of prodromal clusters was compared between SMD groups with linear mixed-effects models. 26,975 individuals diagnosed with ICD-10 SMD were followed up for up to 12 years (UMD = 13,422; BMD = 2506; PSY = 11,047; median[IQR] age 39.8[23.7] years; 55% female; 52% white). The duration of the UMD prodrome (18[36] months) was shorter than BMD (26[35], d = 0.21) and PSY (24[38], d = 0.18). Most individuals presented with multiple first prodromal clusters, with the most common being non-specific ('other'; 88% UMD, 85% BMD, 78% PSY). The only first prodromal cluster that showed a medium-sized difference between the three SMD groups was positive symptoms (f = 0.30). Time course analysis showed an increase in prodromal cluster occurrences approaching SMD onset. Feature occurrence across the prodromal period showed small/negligible differences between SMD groups, suggesting that most features are transdiagnostic, except for positive symptoms (e.g. paranoia, f = 0.40). Taken together, our findings show minimal differences in the duration and first presentation of the SMD prodromes as recorded in secondary mental health care. All the prodromal clusters intensified as individuals approached SMD onset, and all the prodromal features other than positive symptoms are transdiagnostic. These results support proposals to develop transdiagnostic preventive services for affective and psychotic disorders detected in secondary mental healthcare.

Recent Evidence of Non-Rapid Eye Movement Sleep Oscillation Abnormalities in Psychiatric Disorders

PURPOSE OF REVIEW

We review recent studies published from 2019 to 2024 examining slow waves and sleep spindles abnormalities across neurodevelopmental, mood, trauma-related, and psychotic disorders using polysomnography and Electroencephalogram (EEG).

RECENT FINDINGS

Individuals with attention-deficit/hyperactivity disorder (ADHD) showed higher slow-spindle activity, while findings on slow-wave activity were mixed. Individuals with autism spectrum disorder (ASD) showed inconsistent results with some evidence of lower spindle chirp and slow-wave amplitude. Individuals with depression displayed lower slow-wave and spindle parameters mostly in medicated patients. Individuals with post-traumatic stress disorder (PTSD) showed higher spindle frequency and activity, which were associated with their clinical symptoms. Psychotic disorders demonstrated the most consistent alterations, with lower spindle density, amplitude, and duration across illness stages that correlated with patients' symptom severity and cognitive deficits, whereas lower slow-wave measures were present in the early phases of the disorders. Sleep spindle and slow-wave abnormalities are present across psychiatric populations, with the most consistent alterations observed in psychotic disorders. Larger studies with standardized methodologies and longitudinal assessments are needed to establish the potential of these oscillations as neurophysiological biomarkers and/or treatment targets.

The Role of Childhood Trauma in Affective Stress Recovery in Early Psychosis: An Experience Sampling Study

BACKGROUND AND HYPOTHESES

Affective recovery, operationalized as the time needed for affect to return to baseline levels after daily stressors, may be a putative momentary representation of resilience. This study aimed to investigate affective recovery in positive and negative affect across subclinical and clinical stages of psychosis and whether this is associated with exposure to childhood trauma (sexual, physical, and emotional abuse).

STUDY DESIGN

We used survival analysis to predict the time-to-recovery from a daily event-related stressor in a pooled sample of 3 previously conducted experience sampling studies including 113 individuals with first-episode psychosis, 162 at-risk individuals, and 94 controls.

STUDY RESULTS

Negative affective recovery (ie, return to baseline following an increase in negative affect) was longer in individuals with first-episode psychosis compared with controls (hazard ratio [HR] = 1.71, 95% confidence interval [CI; 1.03, 2.61], P = .04) and in at-risk individuals exposed to high vs low levels of emotional abuse (HR = 1.31, 95% CI [1.06, 1.62], P = .01). Positive affective recovery (ie, return to baseline following a decrease in positive affect) did not differ between groups and was not associated with childhood trauma.

CONCLUSIONS

Our results give first indications that negative affective recovery may be a putative momentary representation of resilience across stages of psychosis and may be amplified in at-risk individuals with prior experiences of emotional abuse. Understanding how affective recovery contributes to the development of psychosis may help identify new targets for prevention and intervention to buffer risk or foster resilience in daily life.

Neural dysfunction underlying working memory processing at different stages of the illness course in schizophrenia: a comparative meta-analysis

Schizophrenia, as a chronic and persistent disorder, exhibits working memory deficits across various stages of the disorder, yet the neural mechanisms underlying these deficits remain elusive with inconsistent neuroimaging findings. We aimed to compare the brain functional changes of working memory in patients at different stages: clinical high risk, first-episode psychosis, and long-term schizophrenia, using meta-analyses of functional magnetic resonance imaging studies. Following a systematic literature search, 56 whole-brain task-based functional magnetic resonance imaging studies (15 for clinical high risk, 16 for first-episode psychosis, and 25 for long-term schizophrenia) were included. The separate and pooled neurofunctional mechanisms among clinical high risk, first-episode psychosis, and long-term schizophrenia were generated by Seed-based d Mapping toolbox. The clinical high risk and first-episode psychosis groups exhibited overlapping hypoactivation in the right inferior parietal lobule, right middle frontal gyrus, and left superior parietal lobule, indicating key lesion sites in the early phase of schizophrenia. Individuals with first-episode psychosis showed lower activation in left inferior parietal lobule than those with long-term schizophrenia, reflecting a possible recovery process or more neural inefficiency. We concluded that SCZ represent as a continuum in the early stage of illness progression, while the neural bases are inversely changed with the development of illness course to long-term course.

Associations between disturbed sleep and attenuated psychotic experiences in people at clinical high risk for psychosis

BACKGROUND

Pre-diagnostic stages of psychotic illnesses, including 'clinical high risk' (CHR), are marked by sleep disturbances. These sleep disturbances appear to represent a key aspect in the etiology and maintenance of psychotic disorders. We aimed to examine the relationship between self-reported sleep dysfunction and attenuated psychotic symptoms (APS) on a day-to-day basis.

METHODS

Seventy-six CHR young people completed the Experience Sampling Methodology (ESM) component of the European Union Gene-Environment Interaction Study, collected through PsyMate® devices, prompting sleep and symptom questionnaires 10 times daily for 6 days. Bayesian multilevel mixed linear regression analyses were performed on time-variant ESM data using the brms package in R. We investigated the day-to-day associations between sleep and psychotic experiences bidirectionally on an item level. Sleep items included sleep onset latency, fragmentation, and quality. Psychosis items assessed a range of perceptual, cognitive, and bizarre thought content common in the CHR population.

RESULTS

Two of the seven psychosis variables were unidirectionally predicted by previous night's number of awakenings: every unit increase in number of nightly awakenings predicted a 0.27 and 0.28 unit increase in feeling unreal or paranoid the next day, respectively. No other sleep variables credibly predicted next-day psychotic symptoms or vice-versa.

CONCLUSION

In this study, the relationship between sleep disturbance and APS appears specific to the item in question. However, some APS, including perceptual disturbances, had low levels of endorsement amongst this sample. Nonetheless, these results provide evidence for a unidirectional relationship between sleep and some APS in this population.

Insomnia and aggression in stable schizophrenic patients: The mediating role of quality of life

Aggression in schizophrenia patients is an issue of concern. Previous studies have shown that aggression in schizophrenia patients may be related to insomnia and quality of life to different extents. This study aimed to explore the potential mediating role of quality of life in the relationship between aggression and insomnia among schizophrenia patients. Demographic factors affecting aggression in schizophrenia patients were also explored.

PATIENTS AND METHODS

A total of 781 stable patients aged 18-75 who met the ICD10 diagnosis of "schizophrenia" completed the completed questionnaire. Aggression was assessed using the Modified Overt Aggression Scale (MOAS), sleep was assessed using the Insomnia Severity Index Scale (ISI), and quality of life was assessed using the five Likert options. Descriptive statistics and correlation analysis examined the correlation between aggression and other variables. The mediating role of quality of life in the association between insomnia and aggression was examined by pathway analysis.

RESULTS

A total of 781 patients participated in this study, and approximately 16 % of the schizophrenia patients were aggressive. According to the mediation analysis, the direct effect of insomnia on aggression was 0.147, and the mediating effect of quality of life on insomnia and aggression was 0.021. Specifically, for the four dimensions of the MOAS, the direct effects of insomnia on verbal aggression, aggression toward property, and aggression toward oneself were 0.028, 0.032, and 0.023, respectively, with mediating effects of 0.003, 0.007, and 0.006, respectively, and no mediating effect on physical aggression was found.

CONCLUSION

This study showed that insomnia significantly influenced aggression in schizophrenia patients. Quality of life significantly mediated insomnia and aggression and played a vital role in moderating aggression. Therefore, we suggest that in the future, improving aggression in schizophrenia patients, while paying attention to the importance of sleep, could start with improving quality of life to address this problem from multiple perspectives.

Sleep spindles as neurophysiological biomarkers of schizophrenia

Schizophrenia (SCZ) is a complex psychiatric disorder characterized by a wide range of clinical symptoms, including disrupted sleep. In recent years, there has been growing interest in assessing alterations in sleep parameters in patients with SCZ. Sleep spindles are brief (0.5-2 s) bursts of 12- to 16-Hz rhythmic electroencephalogram (EEG) oscillatory activity occurring during non-rapid eye movement (NREM) sleep. Spindles have been implicated in several critical brain functions, including learning, memory and plasticity, and are thought to reflect the integrity of underlying thalamocortical circuits. This review aims to provide an overview of the current research investigating sleep spindles in SCZ. After briefly describing the neurophysiological features of sleep spindles, I will discuss alterations in spindle characteristics observed in SCZ, their associations with the clinical symptomatology of these patients and their putative underlying neuronal and molecular mechanisms. I will then discuss the utility of sleep spindle measures as predictors of treatment response and disease progression. Finally, I will highlight future directions for research in this emerging field, including the prospect of utilizing sleep spindles as neurophysiological biomarkers of SCZ.

A Thalamocortical Perspective on Sleep Spindle Alterations in Neurodevelopmental Disorders

Purpose of Review

Neurodevelopmental disorders are a group of conditions that affect the development and function of the nervous system, typically arising early in life. These disorders can have various genetic, environmental, and/or neural underpinnings, which can impact the thalamocortical system. Sleep spindles, brief bursts of oscillatory activity that occur during NREM sleep, provide a unique in vivo measure of the thalamocortical system. In this manuscript, we review the development of the thalamocortical system and sleep spindles in rodent models and humans. We then utilize this as a foundation to discuss alterations in sleep spindle activity in four of the most pervasive neurodevelopmental disorders-intellectual disability, attention deficit hyperactivity disorder, autism, and schizophrenia.

Recent Findings

Recent work in humans has shown alterations in sleep spindles across several neurodevelopmental disorders. Simultaneously, rodent models have elucidated the mechanisms which may underlie these deficits in spindle activity. This review merges recent findings from these two separate lines of research to draw conclusions about the pathogenesis of neurodevelopmental disorders.

Summary

We speculate that deficits in the thalamocortical system associated with neurodevelopmental disorders are exquisitely reflected in sleep spindle activity. We propose that sleep spindles may represent a promising biomarker for drug discovery, risk stratification, and treatment monitoring.

Reduced slow wave density is associated with worse positive symptoms in clinical high risk: An objective readout of symptom severity for early treatment interventions?

Individuals at clinical high risk for psychosis (CHR) present subsyndromal psychotic symptoms that can escalate and lead to the transition to a diagnosable psychotic disorder. Identifying biological parameters that are sensitive to these symptoms can therefore help objectively assess their severity and guide early interventions in CHR. Reduced slow wave oscillations (∼1 Hz) during non-rapid eye movement sleep were recently observed in first-episode psychosis patients and were linked to the intensity of their positive symptoms. Here, we collected overnight high-density EEG recordings from 37 CHR and 32 healthy control (HC) subjects and compared slow wave (SW) activity and other SW parameters (i.e., density and negative peak amplitude) between groups. We also assessed the relationships between clinical symptoms and SW parameters in CHR. While comparisons between HC and the entire CHR group showed no SW differences, CHR individuals with higher positive symptom severity (N = 18) demonstrated a reduction in SW density in an EEG cluster involving bilateral prefrontal, parietal, and right occipital regions compared to matched HC individuals. Furthermore, we observed a negative correlation between SW density and positive symptoms across CHR individuals, suggesting a potential target for early treatment interventions.

The sleep-circadian interface: A window into mental disorders

Sleep, circadian rhythms, and mental health are reciprocally interlinked. Disruption to the quality, continuity, and timing of sleep can precipitate or exacerbate psychiatric symptoms in susceptible individuals, while treatments that target sleep-circadian disturbances can alleviate psychopathology. Conversely, psychiatric symptoms can reciprocally exacerbate poor sleep and disrupt clock-controlled processes. Despite progress in elucidating underlying mechanisms, a cohesive approach that integrates the dynamic interactions between psychiatric disorder with both sleep and circadian processes is lacking. This review synthesizes recent evidence for sleep-circadian dysfunction as a transdiagnostic contributor to a range of psychiatric disorders, with an emphasis on biological mechanisms. We highlight observations from adolescent and young adults, who are at greatest risk of developing mental disorders, and for whom early detection and intervention promise the greatest benefit. In particular, we aim to a) integrate sleep and circadian factors implicated in the pathophysiology and treatment of mood, anxiety, and psychosis spectrum disorders, with a transdiagnostic perspective; b) highlight the need to reframe existing knowledge and adopt an integrated approach which recognizes the interaction between sleep and circadian factors; and c) identify important gaps and opportunities for further research.

The schizophrenia syndrome, circa 2024: What we know and how that informs its nature

With new data about different aspects of schizophrenia being continually generated, it becomes necessary to periodically revisit exactly what we know. Along with a need to review what we currently know about schizophrenia, there is an equal imperative to evaluate the construct itself. With these objectives, we undertook an iterative, multi-phase process involving fifty international experts in the field, with each step building on learnings from the prior one. This review assembles currently established findings about schizophrenia (construct, etiology, pathophysiology, clinical expression, treatment) and posits what they reveal about its nature. Schizophrenia is a heritable, complex, multi-dimensional syndrome with varying degrees of psychotic, negative, cognitive, mood, and motor manifestations. The illness exhibits a remitting and relapsing course, with varying degrees of recovery among affected individuals with most experiencing significant social and functional impairment. Genetic risk factors likely include thousands of common genetic variants that each have a small impact on an individual's risk and a plethora of rare gene variants that have a larger individual impact on risk. Their biological effects are concentrated in the brain and many of the same variants also increase the risk of other psychiatric disorders such as bipolar disorder, autism, and other neurodevelopmental conditions. Environmental risk factors include but are not limited to urban residence in childhood, migration, older paternal age at birth, cannabis use, childhood trauma, antenatal maternal infection, and perinatal hypoxia. Structural, functional, and neurochemical brain alterations implicate multiple regions and functional circuits. Dopamine D-2 receptor antagonists and partial agonists improve psychotic symptoms and reduce risk of relapse. Certain psychological and psychosocial interventions are beneficial. Early intervention can reduce treatment delay and improve outcomes. Schizophrenia is increasingly considered to be a heterogeneous syndrome and not a singular disease entity. There is no necessary or sufficient etiology, pathology, set of clinical features, or treatment that fully circumscribes this syndrome. A single, common pathophysiological pathway appears unlikely. The boundaries of schizophrenia remain fuzzy, suggesting the absence of a categorical fit and need to reconceptualize it as a broader, multi-dimensional and/or spectrum construct.

Poor sleep quality in schizophrenia patients: A systematic review and meta-analyses of epidemiological and case-control studies

OBJECTIVE

Poor sleep quality is common in patients with schizophrenia but estimated prevalence rates in this population have been mixed. This systematic review and meta-analysis examined the prevalence of poor sleep quality in schizophrenia samples and moderators of prevalence from epidemiological studies as well as the risk of poor sleep quality in schizophrenia patients based on case-control studies.

METHODS

Both international (PubMed, Web of Science, PsycINFO, EMBASE) and Chinese databases [Chinese Nation knowledge Infrastructure (CNKI) and WANFANG] were systematically searched. Studies that estimated the prevalence of poor sleep quality in schizophrenia were analyzed using a random effects model. Funnel plots and Egger's tests were used to assess publication bias. Statistical analyses were performed using R software.

RESULTS

In total, 23 epidemiological studies and nine case-control studies were included. Based on the epidemiological studies, the pooled overall prevalence of poor sleep quality was 63.4 % [95 % confidence interval (CI): 57.0 %-69.9 %]. Additionally, based on the nine case-control studies, schizophrenia patients had a significantly higher risk for poor sleep quality compared to healthy controls [odd ratio (OR) = 4.5; 95%CI: 2.4-8.3; P < 0.0001].

CONCLUSION

Poor sleep quality is common among schizophrenia patients. Considering negative outcomes caused by poor sleep quality, regular screening on poor sleep quality should be conducted and effective interventions should be provided to those in need.

Altered Sleep Oscillations as Neurophysiological Biomarkers of Schizophrenia

Sleep spindles and slow waves are the two main oscillatory activities occurring during nonrapid eye movement (NREM) sleep. Here, we will first describe the electrophysiological characteristics of these sleep oscillations along with the neurophysiological and molecular mechanisms underlying their generation and synchronization in the healthy brain. We will then review the extant evidence of deficits in sleep spindles and, to a lesser extent, slow waves, including in slow wave-spindle coupling, in patients with Schizophrenia (SCZ) across the course of the disorder, from at-risk to chronic stages. Next, we will discuss how these sleep oscillatory deficits point to defects in neuronal circuits within the thalamocortical network as well as to alterations in molecular neurotransmission implicating the GABAergic and glutamatergic systems in SCZ. Finally, after explaining how spindle and slow waves may represent neurophysiological biomarkers with predictive, diagnostic, and prognostic potential, we will present novel pharmacological and neuromodulatory interventions aimed at restoring sleep oscillatory deficits in SCZ, which in turn may serve as target engagement biomarkers to ameliorate the clinical symptoms and the quality of life of individuals affected by this devastating brain disorder.

A spectrum of altered non-rapid eye movement sleep in schizophrenia

Background

Multiple facets of sleep neurophysiology, including electroencephalography (EEG) metrics such as non-rapid eye movement (NREM) spindles and slow oscillations (SO), are altered in individuals with schizophrenia (SCZ). However, beyond group-level analyses which treat all patients as a unitary set, the extent to which NREM deficits vary among patients is unclear, as are their relationships to other sources of heterogeneity including clinical factors, illness duration and ageing, cognitive profiles and medication regimens. Using newly collected high density sleep EEG data on 103 individuals with SCZ and 68 controls, we first sought to replicate our previously reported (Kozhemiako et. al, 2022) group-level mean differences between patients and controls (original N=130). Then in the combined sample (N=301 including 175 patients), we characterized patient-to-patient variability in NREM neurophysiology.

Results

We replicated all group-level mean differences and confirmed the high accuracy of our predictive model (Area Under the ROC Curve, AUC = 0.93 for diagnosis). Compared to controls, patients showed significantly increased between-individual variability across many (26%) sleep metrics, with patterns only partially recapitulating those for group-level mean differences. Although multiple clinical and cognitive factors were associated with NREM metrics including spindle density, collectively they did not account for much of the general increase in patient-to-patient variability. Medication regimen was a greater (albeit still partial) contributor to variability, although original group mean differences persisted after controlling for medications. Some sleep metrics including fast spindle density showed exaggerated age-related effects in SCZ, and patients exhibited older predicted biological ages based on an independent model of ageing and the sleep EEG.

Conclusion

We demonstrated robust and replicable alterations in sleep neurophysiology in individuals with SCZ and highlighted distinct patterns of effects contrasting between-group means versus within-group variances. We further documented and controlled for a major effect of medication use, and pointed to greater age-related change in NREM sleep in patients. That increased NREM heterogeneity was not explained by standard clinical or cognitive patient assessments suggests the sleep EEG provides novel, nonredundant information to support the goals of personalized medicine. Collectively, our results point to a spectrum of NREM sleep deficits among SCZ patients that can be measured objectively and at scale, and that may offer a unique window on the etiological and genetic diversity that underlies SCZ risk, treatment response and prognosis.

The relationship between internet gaming disorder and psychotic experiences: cyberbullying and insomnia severity as mediators

BACKGROUND

The nature of the relationship between Internet Gaming Disorder (IGD) and psychosis is unclear so far. There is evidence that greater time spent in playing video games may expose players to both insomnia and a toxic online environment with widespread cyberbullying. These two possible consequences of IGD may, in turn, be associated with greater psychotic experiences (PE). Based on this theoretical framework, the present study proposed to contribute the body of the knowledge in this area, by testing the possible indirect effects of insomnia severity, cyber-victimization and cyberbullying in the cross-sectional association between IGD and PE in a sample of Tunisian university students.

METHOD

We conducted a cross-sectional study over 4 months (February-May 2022). The Arabic versions of the Brief Symptom Inventory, the Internet Gaming disorder-20 Test, the Insomnia Severity Index, and the Revised Cyber Bullying Inventory-II were administered to a total of 851 students (mean age = 21.26 ± 1.68 years, 53.7% females).

RESULTS

We found that 25% of students were at risk of IGD, and 1.8% had an IGD. The results of the mediation analysis showed that insomnia severity fully mediated the association between IGD and paranoid ideation. Higher IGD was significantly associated with more insomnia severity, which was, in turn, significantly associated with more paranoid ideation. Cyberbullying partly mediated the association between IGD and psychoticism. Higher IGD scores were significantly associated with more cyberbullying, which was, in turn, significantly associated with more psychoticism. Finally, greater IGD was significantly and directly associated with higher psychoticism.

CONCLUSION

Our findings suggest that insomnia and cyberbullying may be regarded as potential targets for youth mental health promotion, as well as community-focused prevention and early intervention in psychosis. More particular attention should be devoted to the huge potential for engaging in cyberbullying among online gamers. Sleep deprivation should be prevented, assessed and treated in heavy gamers.

Sleep disturbance in schizophrenia spectrum disorders: more than just a symptom?

Sleep disturbance is commonly reported in patients with schizophrenia spectrum disorder (SSD) in the clinical setting. Sleep features can be assessed subjectively, with self-report sleep questionnaires, and objectively with actigraphy and electroencephalogram recordings. Traditionally, electroencephalogram studies have focused on sleep architecture. More recently, numerous studies have investigated alterations in sleep-specific rhythms, including electroencephalogram oscillations, such as sleep spindles and slow waves, in patients with SSD compared with control subjects. Here, I briefly discuss how sleep disturbance is highly prevalent in patients with SSD and I present findings from studies demonstrating abnormalities in sleep architecture and sleep-oscillatory rhythms, with an emphasis on sleep spindles and slow-wave deficits, in these patients. This increasing body of evidence highlights the importance of sleep disturbance in SSD and points to several future research directions with related clinical implications, thus showing that sleep disturbance is more than just a symptom in these patients.

Clinical Evaluation of Sleep Disorders in Parkinson’s Disease

The paradigm of the framing of Parkinson’s disease (PD) has undergone significant revision in recent years, making this neurodegenerative disease a multi-behavioral disorder rather than a purely motor disease. PD affects not only the “classic” substantia nigra at the subthalamic nuclei level but also the nerve nuclei, which are responsible for sleep regulation. Sleep disturbances are the clinical manifestations of Parkinson’s disease that most negatively affect the quality of life of patients and their caregivers. First-choice treatments for Parkinson’s disease determine amazing effects on improving motor functions. However, it is still little known whether they can affect the quantity and quality of sleep in these patients. In this perspective article, we will analyze the treatments available for this specific clinical setting, hypothesizing a therapeutic approach in relation to neurodegenerative disease state.