Shared and distinct abnormalities in sleep-wake patterns and their relationship with the negative symptoms of Schizophrenia Spectrum Disorder patients

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.

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 and physical activity patterns in relation to daily-life symptoms in psychosis: An actigraphy and experience sampling study

Sleep disturbances and reduced physical activity (PA) are important risk factors for poor physical and mental health outcomes in people with psychosis. However, the precise interrelations between sleep, PA and psychopathology remain unclear. This study combined experience sampling (ESM) and actigraphy in thirty-two patients with a schizophrenia spectrum disorder to investigate interrelations of day-to-day variations in actigraphic estimates of PA and sleep and psychotic and affective symptoms. Multilevel mixed-models show that subjects reported more positive affect on more physically active days. Unexpectedly, participants reported worse next-day negative affect and/or psychotic symptoms after nights with higher sleep continuity, as consistently indicated by sleep efficiency and the mean duration of bouts of wake and sleep. Lastly, PA was higher after nights with higher sleep continuity and shorter total sleep duration. These results highlight that modifiable lifestyle factors such as PA and sleep have an intricate, but clinically relevant relationship with psychotic and affective symptoms. Future studies are needed to further examine the complex effects of these behaviors in order to develop effective, targeted treatment strategies to improve clinical outcome in psychosis.

A systematic review of passive data for remote monitoring in psychosis and schizophrenia

There is increasing use of digital tools to monitor people with psychosis and schizophrenia remotely, but using this type of data is challenging. This systematic review aimed to summarise how studies processed and analysed data collected through digital devices. In total, 203 articles collecting passive data through smartphones or wearable devices, from participants with psychosis or schizophrenia were included in the review. Accelerometers were the most common device (n = 115 studies), followed by smartphones (n = 46). The most commonly derived features were sleep duration (n = 50) and time spent sedentary (n = 41). Thirty studies assessed data quality and another 69 applied data quantity thresholds. Mixed effects models were used in 21 studies and time-series and machine-learning methods were used in 18 studies. Reporting of methods to process and analyse data was inconsistent, highlighting a need to improve the standardisation of methods and reporting in this area of research.

Emotional experiences in male and female participants with schizophrenia spectrum disorders and healthy controls: an experience sampling method study

AIM

Schizophrenia spectrum disorders (SSD) are associated with disturbances in emotional experience, but sex differences and comparisons to healthy controls (HC) remain poorly explored. This exploratory study used Experience Sampling Method (ESM) to examine emotional variability, instability and daily/hourly patterns of positive and negative emotions across sexes in SSD and HC.

METHODS

A total of 103 SSD participants (47.9%) were compared to 112 HC (52.1%), matched for sex and age. Data on sociodemographics, clinical status, functioning and quality of life were collected. ESM assessed emotional experiences over one week.

RESULTS

For positive emotions, HC males reported higher levels on weekdays and morning-to-midday hours, whereas no sex differences emerged in SSD. Males with SSD showed greater weekly variability in positive emotions than HC males, while no significant differences were found among females. For negative emotions, females with SSD exhibited greater daily variability than female HC, with no significant sex differences within HC or SSD. Regarding emotional instability, female HC displayed higher instability than HC males, while no significant sex differences emerged in SSD.

CONCLUSION

This study shows significant sex differences in emotional experiences among SSD and HC, with different sex patterns in SSD. Targeted, sex-specific interventions are crucial for improving emotional regulation and treatment outcomes in SSD.Trial registration: ISRCTN.org identifier: ISRCTN21141466.

Definition, assessment and treatment of cognitive impairment associated with schizophrenia: expert opinion and practical recommendations

A considerable proportion of patients with schizophrenia perform below population norms on standardized neuropsychological tests, and the performance of those performing within normal range is lower than predicted based on parental education. Cognitive impairment predates the onset of psychosis, is observed during symptom remission and in non-affected first-degree relatives of patients. At the present time, cognitive deficits are regarded as key features of schizophrenia, important determinants of poor psychosocial outcome and targets for both pharmacological and non-pharmacological treatment strategies. A group of eight key opinion leaders reviewed and discussed latest advances in scientific research and current good clinical practices on assessment, management, and treatment of CIAS. In the present paper they summarize the current evidence, identify main gaps between current knowledge and mental health services clinical practice, and provide practical recommendations to reduce the gap.

Investigating Rhythmicity in App Usage to Predict Depressive Symptoms: Protocol for Personalized Framework Development and Validation Through a Countrywide Study

BACKGROUND

Understanding a student's depressive symptoms could facilitate significantly more precise diagnosis and treatment. However, few studies have focused on depressive symptom prediction through unobtrusive systems, and these studies are limited by small sample sizes, low performance, and the requirement for higher resources. In addition, research has not explored whether statistically significant rhythms based on different app usage behavioral markers (eg, app usage sessions) exist that could be useful in finding subtle differences to predict with higher accuracy like the models based on rhythms of physiological data.

OBJECTIVE

The main objective of this study is to explore whether there exist statistically significant rhythms in resource-insensitive app usage behavioral markers and predict depressive symptoms through these marker-based rhythmic features. Another objective of this study is to understand whether there is a potential link between rhythmic features and depressive symptoms.

METHODS

Through a countrywide study, we collected 2952 students' raw app usage behavioral data and responses to the 9 depressive symptoms in the 9-item Patient Health Questionnaire (PHQ-9). The behavioral data were retrieved through our developed app, which was previously used in our pilot studies in Bangladesh on different research problems. To explore whether there is a rhythm based on app usage data, we will conduct a zero-amplitude test. In addition, we will develop a cosinor model for each participant to extract rhythmic parameters (eg, acrophase). In addition, to obtain a comprehensive picture of the rhythms, we will explore nonparametric rhythmic features (eg, interdaily stability). Furthermore, we will conduct regression analysis to understand the association of rhythmic features with depressive symptoms. Finally, we will develop a personalized multitask learning (MTL) framework to predict symptoms through rhythmic features.

RESULTS

After applying inclusion criteria (eg, having app usage data of at least 2 days to explore rhythmicity), we kept the data of 2902 (98.31%) students for analysis, with 24.48 million app usage events, and 7 days' app usage of 2849 (98.17%) students. The students are from all 8 divisions of Bangladesh, both public and private universities (19 different universities and 52 different departments). We are analyzing the data and will publish the findings in a peer-reviewed publication.

CONCLUSIONS

Having an in-depth understanding of app usage rhythms and their connection with depressive symptoms through a countrywide study can significantly help health care professionals and researchers better understand depressed students and may create possibilities for using app usage-based rhythms for intervention. In addition, the MTL framework based on app usage rhythmic features may more accurately predict depressive symptoms due to the rhythms' capability to find subtle differences.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/51540.

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.

Positivity, daily time use, mood, and functioning in patients with schizophrenia spectrum disorders: Results from the diapason multicentric study

BACKGROUND

Positivity (POS) indicates the proclivity to see life and experiences in a positive light. There is limited research on its effects on individuals with Schizophrenia Spectrum Disorders (SSD). Very little is known about the relationship between POS and daily activities in people with SSD.

AIM

The study aims to compare the POS rated by patients with SSD with those obtained in an Italian normative sample matched by age and sex and to use the Ecological Momentary Assessment (EMA) to investigate the association between POS and daily time use (i.e. productive activities, leisure activities), functioning and mood in individuals with SSD.

METHOD

620 SSD patients were recruited from mental health services in Italy as part of the DiAPAson project. POS, symptom severity, functioning, and quality of life (QoL) were assessed. POS scores were compared to a normative sample of 5,002 Italian citizens. Additionally, a subset of 102 patients underwent 7-day assessments using mobile EMA.

RESULTS

People with SSD did not significantly differ from the Italian normative sample in POS levels (0.035, p = .190). POS showed a significant inverse association with support network (-0.586, p = .036) and symptomatology (BPRS -0.101; 95% p < .001; BNSS B = -0.113, p < .001). A significant direct association was found between POS and QoL (B = 0.310, p < .001) and functioning (B = 0.058, p < .001). In the subsample using EMA, POS ratings showed significant associations with Positive Emotions (B = 0.167, p < .001) and Negative Emotions (B = -0.201, p < .001).

CONCLUSION

People with SSD exhibited comparable levels of POS to the normative sample. Higher POS was linked to better functioning, QoL, fewer severe symptoms, and increased positive emotions. However, it did not relate to increased productivity or engagement in leisure activities. Further research is needed to understand the relationship between POS and time use in individuals with SSD.

Schizophrenia and disruption of circadian rhythms: An overview of genetic, metabolic and clinical signs

A molecular clock in the suprachiasmatic nucleus of the anterior hypothalamus, which is entrained by the dark-light cycle and controls the sleep-wake cycle, regulates circadian rhythms. The risk of developing mental disorders, such as schizophrenia, has long been linked to sleep abnormalities. Additionally, a common aspect of mental disorders is sleep disturbance, which has a direct impact on the intensity of the symptoms and the quality of life of the patient. This relationship can be explained by gene alterations such as CLOCK in schizophrenia which are also important components of the physiological circadian rhythm. The function of dopamine and adenosine in circadian rhythm should also be noted, as these hypotheses are considered to be the most popular theories explaining schizophrenia pathogenesis. Therefore, determining the presence of a causal link between the two can be key to identifying new potential targets in schizophrenia therapy, which can open new avenues for clinical research as well as psychiatric care. We review circadian disruption in schizophrenia at the genetic, metabolic, and clinical levels. We summarize data about clock and clock-controlled genes' alterations, neurotransmitter systems' impairments, and association with chronotype in schizophrenia patients. Our findings demonstrate that in schizophrenia either homeostatic or circadian processes of sleep regulation are disturbed. Also, we found an insufficient number of studies aimed at studying the relationship between known biological phenomena of circadian disorders and clinical signs of schizophrenia.

Relationship between rest-activity rhythms and cardiorespiratory fitness in middle-aged workers: a cross-sectional study with non-parametric analysis using accelerometers worn on the thigh

BACKGROUND

Rest-activity rhythms are directly related to health risks, but there are limited objective methods to assess them. This study aimed to investigate the relationship between rest-activity rhythms and cardiorespiratory fitness (CRF) in middle-aged workers.

METHODS

Peak oxygen uptake was measured on a treadmill to assess CRF in 254 middle-aged workers who were divided into low, medium, and high-CRF groups based on tertiles. Participants were asked to wear an accelerometer (activPAL) on their thighs for 1 week, and the logarithmically transformed acceleration data were used for the analysis of a 24-hour rest-activity rhythm. Sex, age, body mass index, occupation, smoking status, and alcohol consumption were used as covariates in Model 1, with Model 2 also including walking count on non-workdays. Repeated measures analysis of variance was used to compare time course of rest-activity rhythms changes on workdays between groups, and post-hoc tests were conducted using Bonferroni's correlation.

RESULTS

Higher CRF correlated with increased physical activity. In model 1, higher CRF showed improved interdaily stability, but the significant difference disappeared in model 2 after adjusting for non-workday walking counts. A time-course group comparison showed that the high group had significantly higher activity levels than those of the low group from 6:00 to 8:59 and 17:00 to 17:59 and the medium group from 6:00 to 7:59 and 19:00 to 19:59.

CONCLUSIONS

Workers who have better rest-activity rhythms and engage in higher levels of physical activity on workdays tend to have higher CRF levels. Regular daily routines, influenced by physical activity during holidays, can positively impact cardiopulmonary endurance.

Alexithymia is associated with insomnia in Chinese patients with schizophrenia

Background

Sleep disorders are prevalent among patients with schizophrenia and are associated with several negative consequences. Although, researchers have recently suggested that sleep disorders have a close correlation with alexithymia, and schizophrenia also has a strong correlation with alexithymia, there have been few studies on the relationships between schizophrenia, sleep disorders and alexithymia. Therefore, this study aimed to explore the relationships between psychiatric symptoms, alexithymia and sleep problems in patients with schizophrenia so as to provide a reference for the clinical treatment of this comorbidity.

Methods

In total, 977 patients with schizophrenia were recruited for this study. The Insomnia Severity Index (ISI) was used to assess sleep disorders, and the Positive and Negative Syndrome Scale (PANSS), Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and Toronto Alexithymia Scale (TAS) were used to evaluate clinical symptoms, cognitive functions and the ability to express emotion, respectively.

Results

The results indicated that the PANSS subscales (G-subscore) and TAS group were risk factors for insomnia in schizophrenia patients (all p < 0.05). The mediation model showed the standardized path coefficients from schizophrenia to alexithymia (β = 0.104, p < 0.001) and from alexithymia to insomnia (β = 0.038, p < 0.001) were statistically significant.

Conclusion

The results of this study indicated that alexithymia is associated with sleep disturbance in patients with schizophrenia. These findings may provide a new avenue for the treatment of schizophrenia patients with sleep disorders.

Can circadian rhythm predict changes in neurocognitive functioning in bipolar disorder: protocol of a 12-month longitudinal cohort study based on research domain criteria

Introduction: Bipolar disorder (BD) is a prevalent and disabling mental disorder characterized by disrupted circadian rhythms and impaired neurocognitive features, both of which fall under the major domains of Research Domain Criteria (RDoC). However, there is limited evidence regarding the interaction between circadian rhythms and long-term neurocognitive functioning. Therefore, this longitudinal cohort study protocol aims to explore whether circadian rhythm can predict changes in neurocognitive functioning over time in patients with BD.Methods: This study adopts a longitudinal cohort design, aiming to recruit 100 BD patients in either depressive or remitted states. Participants will undergo evaluations from clinical, circadian rhythm, and neurocognitive perspectives at baseline, 6-month, and 12-month follow-ups, involving questionnaires, actigraphy, and computed neurocognitive tests. We will examine both cross-sectional and longitudinal associations between participants' circadian rhythm patterns and neurocognitive functioning. Statistical analyses will employ Spearman correlation and mixed regression models.Discussion: We anticipate that circadian rhythms may serve as predictors of neurocognitive functioning changes. The findings of this study could offer supplementary insights into BD pathophysiology, potential treatment targets, and prediction.Trial Registration: This study has been registered with the Chinese Clinical Trial Registry under the registration code ChiCTR2200064922 on 21st October 2022.