Circadian rest-activity rhythm in individuals at risk for psychosis and bipolar disorder

The circadian system: A neglected player in neurodevelopmental disorders

Patients with neurodevelopmental disorders, such as autism spectrum disorder, often display abnormal circadian rhythms. The role of the circadian system in these disorders has gained considerable attention over the last decades. Yet, it remains largely unknown how these disruptions occur and to what extent they contribute to the disorders' development. In this review, we examine circadian system dysregulation as observed in patients and animal models of neurodevelopmental disorders. Second, we explore whether circadian rhythm disruptions constitute a risk factor for neurodevelopmental disorders from studies in humans and model organisms. Lastly, we focus on the impact of psychiatric medications on circadian rhythms and the potential benefits of chronotherapy. The literature reveals that patients with neurodevelopmental disorders display altered sleep-wake cycles and melatonin rhythms/levels in a heterogeneous manner, and model organisms used to study these disorders appear to support that circadian dysfunction may be an inherent characteristic of neurodevelopmental disorders. Furthermore, the pre-clinical and clinical evidence indicates that circadian disruption at the environmental and genetic levels may contribute to the behavioural changes observed in these disorders. Finally, studies suggest that psychiatric medications, particularly those prescribed for attention-deficit/hyperactivity disorder and schizophrenia, can have direct effects on the circadian system and that chronotherapy may be leveraged to offset some of these side effects. This review highlights that circadian system dysfunction is likely a core pathological feature of neurodevelopmental disorders and that further research is required to elucidate this relationship.

Sleep Problems, Suicidal Ideation, and Psychopathology in First-Episode Psychosis

BACKGROUND AND HYPOTHESIS

Insomnia occurs frequently in the clinical course of schizophrenia. A growing literature has found associations between insomnia, suicidal ideation and behavior, and psychopathology in schizophrenia. We explored associations between sleep problems, suicidal ideation, and psychopathology in a cohort of patients with first-episode psychosis.

STUDY DESIGN

We performed a secondary analysis of data for n = 403 subjects with data from the Recovery After an Initial Schizophrenia Episode study using regression models.

STUDY RESULTS

The prevalence of sleep problems and suicidal ideation at baseline was 57% and 15%, respectively. After controlling for potential confounders, in the study baseline sleep problems were associated with increased odds of suicidal ideation with evidence of a dose-dependent relationship (OR = 2.25, 95% CI 1.15-4.41, P = .018). Over 24 months, sleep problems at any time point were associated with an over 3-fold increased odds of concurrent suicidal ideation (OR = 3.21, 95% CI 1.45-7.14, P = .004). Subjects with persistent sleep problems were almost 14 times more likely to endorse suicidal ideation at least once over the study than those without sleep problems (OR = 13.8, 95% CI 6.5-53.4, P < .001). Sleep problems were also a predictor of higher Positive and Negative Syndrome Scale total (β = 0.13-0.22), positive (β = 0.14-0.25), and general (β = 0.16-0.27) subscale scores at baseline and multiple follow-up visits (P < .01 for each).

CONCLUSIONS

Sleep problems are highly prevalent and associated with suicidal ideation and greater psychopathology in first-episode psychosis. Formal assessment and treatment of insomnia appear relevant to the clinical care of patients with psychosis as a predictor of suicidal ideation and symptom severity.

Circadian rhythmicity in schizophrenia male patients with and without substance use disorder comorbidity

Circadian rhythmicity is associated to clinical variables that play an important role in both schizophrenia (SZ) and substance use disorders (SUD), although the characteristics of the coexistence of these two diagnoses (SZ +) remain mostly unknown. Hence, we studied a sample of 165 male patients divided in three groups each of 55, according to their diagnoses (SZ + , SZ, and SUD), as well as a healthy control (HC; n = 90) group. Alongside with sociodemographic and clinical variables, circadian rhythms were registered through a sleep-wake data structured interview, a circadian typology questionnaire, and distal skin temperature (DST) using the Thermochron iButton every 2 min during 48 h. Analyses showed that SZ + and SZ patients presented a longer sleep (delay in wake-up time) and mostly an intermediate circadian typology, while SUD patients slept less hours, displaying a morning typology. The DST showed the highest daily activation and stability for the SUD group, even when compared with the HC group. The presence of schizophrenia (SZ + and SZ) was related to a DST pattern with a reduced amplitude determined by a wakefulness impairment, which was more pronounced for SZ patients whose sleep period was adequate. The assessment of circadian rhythms in under treatment male patients with SZ should be focused on the diurnal period as a possible marker of either treatment adherence or patient's recovery, irrespective of the presence of a comorbid SUD. Further research with additional objective measures may provide knowledge transferable to therapeutic strategies and could be useful to establish possible endophenotypes in the future.

Progress and Implications from Genetic Studies of Bipolar Disorder

With the advancements in gene sequencing technologies, including genome-wide association studies, polygenetic risk scores, and high-throughput sequencing, there has been a tremendous advantage in mapping a detailed blueprint for the genetic model of bipolar disorder (BD). To date, intriguing genetic clues have been identified to explain the development of BD, as well as the genetic association that might be applied for the development of susceptibility prediction and pharmacogenetic intervention. Risk genes of BD, such as CACNA1C, ANK3, TRANK1, and CLOCK, have been found to be involved in various pathophysiological processes correlated with BD. Although the specific roles of these genes have yet to be determined, genetic research on BD will help improve the prevention, therapeutics, and prognosis in clinical practice. The latest preclinical and clinical studies, and reviews of the genetics of BD, are analyzed in this review, aiming to summarize the progress in this intriguing field and to provide perspectives for individualized, precise, and effective clinical practice.

Circadian rhythms and mood disorders: Time to see the light

The importance of time is ever prevalent in our world, and disruptions to the normal light/dark and sleep/wake cycle have now become the norm rather than the exception for a large part of it. All mood disorders, including seasonal affective disorder (SAD), major depressive disorder (MDD), and bipolar disorder (BD), are strongly associated with abnormal sleep and circadian rhythms in a variety of physiological processes. Environmental disruptions to normal sleep/wake patterns, light/dark changes, and seasonal changes can precipitate episodes. Moreover, treatments that target the circadian system have proven to be therapeutic in certain cases. This review will summarize much of our current knowledge of how these disorders associate with specific circadian phenotypes, as well as the neuronal mechanisms that link the circadian clock with mood regulation. We also discuss what has been learned from therapies that target circadian rhythms and how we may use current knowledge to develop more individually designed treatments.

The relationship between subjective sleep disturbance and attenuated psychotic symptoms after accounting for anxiety and depressive symptoms

BACKGROUND AND HYPOTHESES

Sleep disturbances are increasingly recognized as cooccurring with psychotic symptoms. The potential importance of this relationship is complicated when considering the effects of anxiety and depressive symptoms which commonly present in early-stage illness states. This study aimed to investigate the relationship between self-reported sleep disturbance on the development of attenuated psychotic symptoms (APS) cross-sectionally and longitudinally while adjusting for roles of anxiety and depressive symptoms.

DESIGN

Eight-hundred and two help-seeking young people aged 12 to 25 years who engaged with our Australian early intervention services were included in the study (the "Transitions" cohort). Cross sectional mediation and cross-lagged longitudinal (12-month) mediation models were developed with outcomes being different APS domains.

RESULTS

Only baseline excessive daytime sleepiness predicted later APS when accounting for previous APS, anxiety and depressive symptomatology. Cross sectionally, self-reported sleep disturbance showed both direct and indirect predictive relationships with all APS domains. Partial mediation through anxiety and depression was shown for unusual thought content, perceptual abnormalities, and disorganised speech, while full mediation through depression was shown for non-bizarre ideas.

CONCLUSIONS

The specificity of the relationship between self-reported sleep disturbance on APS highlights the potential for different roles in mechanistic models of psychotic symptom expression. This further indicates the need for further experimental research to illuminate potential causal pathways. Future research should continue to use continuous, symptom level approaches across a range of timeframes to more accurately model the complex dynamics present in the sleep-psychosis relationship.

Meta-analysis of insomnia, suicide, and psychopathology in schizophrenia

PURPOSE OF REVIEW

Insomnia is common in schizophrenia. Insomnia has been associated with suicidal ideation and behavior, as well as greater severity of psychopathology, in schizophrenia. This review performs a meta-analysis of associations between insomnia, suicide, and psychopathology in patients with schizophrenia.

RECENT FINDINGS

We searched major electronic databases from inception until November 2022 for studies of insomnia, suicide, and psychopathology in patients with schizophrenia. Random effects meta-analysis calculating odds ratios (ORs, for suicide) and effect sizes (ESs, for psychopathology) and 95% confidence intervals (CIs) were performed. Ten studies met the inclusion criteria, comprising 3428 patients with schizophrenia. Insomnia was associated with a significant increased odds of suicidal ideation (OR = 1.84, 95% CI 1.28-2.65, P  < 0.01) and suicide attempt or death (OR = 5.83, 95% CI 1.61-2.96, P  < 0.01). Insomnia was also associated with total (ES = 0.16, 95% CI 0.09-0.23, P  < 0.01), positive (ES = 0.14, 95% CI 0.08-0.20, P  = 0.02), and general (ES = 0.17, 95% CI 0.08-0.27, P  < 0.01) psychopathology. In meta-regression analyses, BMI was negatively associated with suicidal ideation. Otherwise, age, sex, and study year were all unrelated to the associations.

SUMMARY

Insomnia is associated with suicide and psychopathology in schizophrenia. Formal assessment and treatment of insomnia appears relevant to the clinical care of schizophrenia.

Association of circadian rhythm with mild cognitive impairment among male pneumoconiosis workers in Hong Kong: a cross-sectional study

Weakened circadian activity rhythms (CARs) were associated with mild cognitive impairment (MCI) in the general population. However, it remains unclear among pneumoconiosis patients. We aimed to address this knowledge gap. This cross-sectional study comprised 186 male pneumoconiosis patients (71.3 ± 7.8 years) and 208 healthy community men. Actigraphy was used to determine CARs parameters (percent rhythm, amplitude, MESOR, and acrophase). Values below the corresponding medians of the CARs parameters represented weakened CARs. The Cantonese version of Mini-Mental State Examination (CMMSE) was used to assess cognitive function, MCI, and the composite outcome of MCI plus cognitive impairment. Compared with the community referents, pneumoconiosis patients had worse cognition and dampened CARs. Compared with the community referents or pneumoconiosis patients with robust circadian rhythm, pneumoconiosis patients with weakened circadian rhythm were consistently associated with increased risk of MCI and the composite outcome. However, significant association was only observed between MESOR and the composite outcome (adjusted OR = 1.99, 95%: 1.04-3.81). A delayed phase of CARs was insignificantly associated with MCI and the composite outcome. Our findings showed that weakened CARs were associated with worse cognitive function among male pneumoconiosis workers. Intervention in improving CARs may mitigate cognitive deterioration in male pneumoconiosis workers.

The Actigraphy-Based Identification of Premorbid Latent Liability of Schizophrenia and Bipolar Disorder

(1) Background and Goal: Several studies have investigated the association of sleep, diurnal patterns, and circadian rhythms with the presence and with the risk states of mental illnesses such as schizophrenia and bipolar disorder. The goal of our study was to examine actigraphic measures to identify features that can be extracted from them so that a machine learning model can detect premorbid latent liabilities for schizotypy and bipolarity. (2) Methods: Our team developed a small wrist-worn measurement device that collects and identifies actigraphic data based on an accelerometer. The sensors were used by carefully selected healthy participants who were divided into three groups: Control Group (C), Cyclothymia Factor Group (CFG), and Positive Schizotypy Factor Group (PSF). From the data they collected, our team performed data cleaning operations and then used the extracted metrics to generate the feature combinations deemed most effective, along with three machine learning algorithms for categorization. (3) Results: By conducting the training, we were able to identify a set of mildly correlated traits and their order of importance based on the Shapley value that had the greatest impact on the detection of bipolarity and schizotypy according to the logistic regression, Light Gradient Boost, and Random Forest algorithms. (4) Conclusions: These results were successfully compared to the results of other researchers; we had a similar differentiation in features used by others, and successfully developed new ones that might be a good complement for further research. In the future, identifying these traits may help us identify people at risk from mental disorders early in a cost-effective, automated way.

Relationships between rest-activity rhythms, sleep, and clinical symptoms in individuals at clinical high risk for psychosis and healthy comparison subjects

Sleep-wake disturbances in individuals at clinical high risk (CHR) of psychosis may relate to increased symptom severity and contribute to disease progression. Here, we examined differences in rest-activity rhythms (RAR) measures, derived from actigraphy, and objective sleep outcomes, derived from electroencephalography (EEG), between 12 CHR and 16 healthy comparison (HC) individuals. Further, we examined the relationships between RAR disturbances, objective sleep outcomes and clinical psychosis symptoms (i.e., negative, positive, disorganized, general symptoms). Sleep-wake behaviors were monitored via actigraphy for 3-7 days (CHR: 5.7 ± 1.7 days; HC: 6.3 ± 1.2 days) prior to participants spending a night in the sleep laboratory, which was monitored with EEG. Separate regressions were used to examine the effect of clinical group on RAR measures and objective sleep outcomes after controlling for age and gender. CHR participants were found to be less active, specifically during the evening (17:00-20:00; β = 1.145, SE = 0.362, p = .004) and nighttime (21:00-24:00; β = 1.152, SE = 0.326, p = .002) relative to HC. Further, CHR participants had more fragmented sleep (wake after sleep onset: β = 0.888, SE = 0.395, p = .034) and more hyperarousal during sleep (NREM gamma activity: β = 1.087, SE = 0.348, p = .005), but these sleep disturbances were not related to reduced activity or clinical symptoms, whereas lower nighttime activity was related to more disorganized symptoms (ρ = -.640, p = .025). Thus, increasing activity through behavioral interventions may have additional beneficial effects on CHR clinical symptoms.

A network analysis of rest-activity rhythms in young people with emerging bipolar disorders

AIMS

Actigraphy studies of individuals with bipolar disorders (BD) suggest that illness progression may be associated with a range of progressive disruptions in 24-hour rest-activity rhythms (RAR). However, those longitudinal studies were undertaken in older adults with extended histories or illness and treatment rather than young people with emerging BD. To our knowledge, this is the first study to use network modelling to examine the statistical associations between clinical phenotypes of BD and different subsets of RAR markers.

METHODS

This study of adolescents and young adults (mean age 22 years; 69% female) uses network modelling to examine which self-rated or actigraphic markers of RAR are more strongly associated with full threshold BD (referred to as Stage 2; N = 15) compared with BD-at risk syndromes (subthreshold presentations referred to as Stage 1; N = 25).

RESULTS

Network analysis demonstrated that some RAR are associated with both stage of BD and a family history of BD (such as longer sleep duration and higher levels of daytime impairment). Markers of circadian rhythmicity indicated that regulation of this system is weaker in Stage 2 compared with Stage 1 of BD.

LIMITATIONS

The small subgroup samples may have undermined the ability to detect some associations between phenotypes and RAR.

CONCLUSIONS

Network modelling may offer a useful strategy for visualizing and analysing patterns of association between RAR and clinical phenotypes defined by stage of illness, familial loading or symptom profile. This could prove useful in understanding the underlying pathophysiology of sleep-wake cycle and circadian rhythm disturbances in BD.

Neurobiological and behavioral mechanisms of circadian rhythm disruption in bipolar disorder: A critical multi-disciplinary literature review and agenda for future research from the ISBD task force on chronobiology

AIM

Symptoms of bipolar disorder (BD) include changes in mood, activity, energy, sleep, and appetite. Since many of these processes are regulated by circadian function, circadian rhythm disturbance has been examined as a biological feature underlying BD. The International Society for Bipolar Disorders Chronobiology Task Force (CTF) was commissioned to review evidence for neurobiological and behavioral mechanisms pertinent to BD.

METHOD

Drawing upon expertise in animal models, biomarkers, physiology, and behavior, CTF analyzed the relevant cross-disciplinary literature to precisely frame the discussion around circadian rhythm disruption in BD, highlight key findings, and for the first time integrate findings across levels of analysis to develop an internally consistent, coherent theoretical framework.

RESULTS

Evidence from multiple sources implicates the circadian system in mood regulation, with corresponding associations with BD diagnoses and mood-related traits reported across genetic, cellular, physiological, and behavioral domains. However, circadian disruption does not appear to be specific to BD and is present across a variety of high-risk, prodromal, and syndromic psychiatric disorders. Substantial variability and ambiguity among the definitions, concepts and assumptions underlying the research have limited replication and the emergence of consensus findings.

CONCLUSIONS

Future research in circadian rhythms and its role in BD is warranted. Well-powered studies that carefully define associations between BD-related and chronobiologically-related constructs, and integrate across levels of analysis will be most illuminating.

A systematic review and meta-analysis of sleep and circadian rhythms disturbances in individuals at high-risk of developing or with early onset of bipolar disorders

Sleep and circadian rhythms disturbances (SCRD) in young people at high risk or with early onset of bipolar disorders (BD) are poorly understood. We systematically searched for studies of self, observer or objective estimates of SCRD in asymptomatic or symptomatic offspring of parents with BD (OSBD), individuals with presentations meeting recognized BD-at-risk criteria (BAR) and youth with recent onset of full-threshold BD (FT-BD). Of 76 studies eligible for systematic review, 35 (46%) were included in random effects meta-analyses. Pooled analyses of self-ratings related to circadian rhythms demonstrated greater preference for eveningness and more dysregulation of social rhythms in BAR and FT-BD groups; analyses of actigraphy provided some support for these findings. Meta-analysis of prospective studies showed that pre-existing SCRD were associated with a 40% increased risk of onset of BD, but heterogeneity in assessments was a significant concern. Overall, we identified longer total sleep time (Hedges g: 0.34; 95% confidence intervals:.1,.57), especially in OSBD and FT-BD and meta-regression analysis indicated the effect sizes was moderated by the proportion of any sample manifesting psychopathology or receiving psychotropic medications. This evolving field of research would benefit from greater attention to circadian rhythm as well as sleep quality measures.

The nature, consequences, mechanisms, and management of sleep disturbances in individuals at-risk for psychosis

There is strong evidence that sleep disturbances are commonly experienced by people with psychosis. Evidence has also shown that sleep disturbances are present since the very early stages of the disease, even during the pre-diagnostic phase. More recently, research involving young individuals at ultra-high risk (UHR) for psychosis documented frequent occurrence of sleep disturbances in this group. The very early onset of sleep disturbances in the course of psychosis has drawn attention to the possible links between sleep parameters and the risk of psychosis. To date, the nature of sleep disturbances characterizing the UHR stage remains unclear, with available studies having yielded mixed findings. In this regard, we performed this review to update the body of literature on the nature of sleep disturbances, their underlying mechanisms, their clinical and functional consequences, the prevention and intervention strategies in the at-risk for psychosis population. Our findings provided further support to the presence of disturbed sleep in UHR individuals as evidenced by subjective and objective sleep measures such as polysomnography, sleep electroencephalograms, and actigraphy. Reviewing the possible mechanisms underlying the relationship between sleep and psychosis emphasized its complex and multifactorial nature which is yet to be determined and understood. Further research is warranted to determine which facets of sleep disturbances are most detrimental to this specific population, and to what extent they can be causal factors or markers of psychosis.

Insomnia, suicidal ideation, and psychopathology in Chinese patients with chronic schizophrenia

OBJECTIVES

Insomnia occurs frequently in the clinical course of schizophrenia. A growing literature has found associations between insomnia, suicidal ideation, and psychopathology in patients with schizophrenia. We explored these associations in a cross-sectional study of a large sample of patients with chronic schizophrenia in China. We hypothesized that insomnia would be associated with an increased odds of current suicidal ideation and higher current psychopathology scores.

METHODS

We recruited 328 inpatients with chronic schizophrenia, all of whom were prescribed psychotropics. We investigated relationships between current insomnia, suicidal ideation over the past two weeks, and current psychopathology for subjects using regression models.

RESULTS

After controlling for multiple potential confounding factors, current insomnia was an indicator of a significant, 2.5-fold increased odds of suicidal ideation (OR = 2.56, 95% CI 1.10-5.95, p = 0.029). Insomnia was also a significant indicator of lifetime suicide attempt (OR = 1.07) as well as higher Positive and Negative Syndrome Scale total (β = 0.134, p = 0.017), positive (β = 0.154, p = 0.006) and general (β = 0.145, p = 0.010) subscale scores.

CONCLUSION

Insomnia is associated with suicidal ideation, lifetime suicide attempt, and higher psychopathology scores in inpatients with chronic schizophrenia. Formal assessment of insomnia appears relevant to the clinical care of patients with schizophrenia as an indicator of suicidal thinking and behavior, depression, and symptom severity.

Greater preference for eveningness is associated with negative symptoms in an ultra-high risk for psychosis sample

AIM

Investigating biological processes in at-risk individuals may help elucidate the aetiological mechanisms underlying psychosis development, refine prediction models and improve intervention strategies. This study examined the associations between sleep disturbances, chronotype, depressive and psychotic symptoms in individuals at ultra-high risk for psychosis.

METHODS

A sample of 81 ultra-high risk patients completed clinical interviews and self-report assessments of chronotype and sleep during the Neurapro clinical trial. Mixed regression was used to investigate the cross-sectional associations between symptoms and sleep disturbances/chronotype.

RESULTS

Sleep disturbances were significantly associated with increased depressive and attenuated positive psychotic symptoms. Greater preference for eveningness was significantly associated with increased negative symptoms, but not with depressive or attenuated positive psychotic symptoms.

CONCLUSION

Sleep disturbances and chronotype may impact the emerging psychopathology experienced by ultra-high risk individuals. Further, the preliminary relationship observed between greater preference for eveningness and negative symptoms offers a unique opportunity to treat negative symptoms through chronobiological approaches.

Examining self-reported social functioning, sleep quality, and psychotic-like experiences in college students

Impairments in social and role functioning have been associated with the prodromal phase of psychosis. Additionally, sleep disturbances impacting daily functioning have been detected across the schizophrenia spectrum. Relationships between social functioning, sleep quality, and psychotic-like experiences (PLEs) in undergraduate-level student populations are less understood. The current project aimed to investigate whether self-reported measures of sleep quality would moderate the relationship between social functioning and PLE endorsement in a community sample of 3042 undergraduate student participants between the ages of 18-35. Participants completed the Social Functioning Scale, the Pittsburgh Sleep Quality Index, and the Prodromal Questionnaire, which indexed PLEs. Bivariate correlations revealed significant associations between social functioning, sleep, and PLEs. As expected, poor sleep and poor social functioning were associated with increased endorsement of PLEs. Contrary to expectation, poor sleep quality was associated with better social functioning. In hierarchical multiple regression models, the interaction between social functioning and sleep was not associated with PLE endorsement. Results indicated that both poor sleep and poor social functioning were significantly associated with PLEs when included in the same model. These findings suggest that poor social functioning and disrupted sleep may act additively to influence PLEs, and that they are both important contributors to psychotic symptoms. Due to deleterious effects of poor sleep on physical and emotional health, these findings provide impetus to further investigate relationships between sleep quality, social functioning, and PLEs using such high-resolution methods as actigraphy, mobile sensing, ecological momentary assessment, and neuroimaging.

Sleep in first-episode schizophrenia patients, their unaffected siblings and healthy controls: A comparison

BACKGROUND

Sleep disturbances in schizophrenia are common throughout its course including in the prodrome, and have been mainly attributed to severity of symptoms and antipsychotic use. We aimed to investigate whether early course patients with schizophrenia and young non-psychotic siblings of patients with schizophrenia also show sleep disturbances and whether sleep correlates with symptoms and functioning.

METHODS

Three study groups, that is, adults newly diagnosed with schizophrenia (n = 54), young non-psychotic siblings of schizophrenia patients (n = 56) and a sample of healthy controls matched to the patients and siblings (n = 61) were evaluated on Horne and Ostberg Morningness-Eveningness Questionnaire, Epworth Sleepiness Scale and Pittsburgh Sleep Quality Index. Severity of symptoms and functioning are assessed using the Positive and Negative Syndrome Scale and the Global Assessment of Functioning Scale, respectively. Age, gender, occupation and marital status were regarded as covariates, and differences between the three groups were evaluated using analysis of covariance.

RESULTS

Early course schizophrenia patients and non-psychotic siblings of schizophrenia patients showed significantly reduced sleep quality relative to healthy controls (P < .001). Schizophrenia patients had significantly higher daytime sleepiness compared to controls (P < .001). Chronotypes in schizophrenia patients and unaffected siblings did not significantly differ from those of the healthy controls.

CONCLUSIONS

Like chronic medicated schizophrenia patients, early course schizophrenia patients and young non-psychotic siblings of individuals with schizophrenia have sleep disturbances. These findings indicate that sleep markers can distinguish unaffected siblings of schizophrenia from healthy controls and serve as an endophenotype for schizophrenia.

Eveningness chronotype preference among individuals at clinical high risk for psychosis

BACKGROUND

Circadian rhythm disturbances are frequently implicated in psychosis. Indeed, research has suggested several avenues by which circadian rhythms may play a mechanistic role as well as contribute to clinical outcomes. Despite its potential role as a risk factor, little is known about circadian rhythm disruption among individuals at clinical high risk (CHR) for psychosis, clinical correlates, or specificity to the psychosis risk syndrome.

METHODS

Eighty-four CHR, 74 individuals with depressive disorders (DD), and 101 non-psychiatric controls (NPC) participated in structured clinical interviews and provided self-reports of chronotype preference. Clinical (positive, negative, anxious, and depressive symptoms) and social functioning outcomes were self-reported and/or clinician-rated. Analyses of covariance controlling for demographics examined group differences in chronotype preference, and partial Pearson correlations evaluated associations with clinical/functional outcomes.

RESULTS

Group differences were observed (F(11, 246) = 8.05, p < .001) with CHR and DD individuals indicating greater eveningness preference compared to NPC. A follow-up sensitivity analysis examining CHR participants with (n = 25) and without (n = 59) depressive disorders indicated no difference in chronotype preference (F(10,72) = 0.00, p = .99). Greater eveningness preference was related to greater negative symptoms (i.e., avolition; r = -0.25) and anxiety (r = -0.34) among CHR individuals.

CONCLUSIONS

CHR and DD display greater preference for eveningness chronotype compared to NPC indicating the disruption is associated with a range of mental health concerns, and not specific to the psychosis-risk syndrome. However, comorbidity with DD did not appear to be driving the finding in the CHR group. Further research may examine shared versus non-shared underlying mechanisms contributing to chronotype preference across psychiatric presentations.

Circadian Characteristics in Patients under Treatment for Substance Use Disorders and Severe Mental Illness (Schizophrenia, Major Depression and Bipolar Disorder)

Dual disorders (substance use and mental illness comorbidity) are a condition that has been strongly associated with severe symptomatology and clinical complications. The study of circadian characteristics in patients with Severe Mental Illness or Substance Use Disorder (SUD) has shown that such variables are related with mood symptoms and worse recovery. In absence of studies about circadian characteristics in patients with dual disorders we examined a sample of 114 male participants with SUD and comorbid Schizophrenia (SZ+; n = 38), Bipolar Disorder (BD+; n = 36) and Major Depressive Disorder (MDD+; n = 40). The possible differences in the sample of patients according to their psychiatric diagnosis, circadian functioning with recordings of distal skin temperature during 48 h (Thermochron iButton^®), circadian typology and sleep-wake schedules were explored. MDD+ patients were more morning-type, while SZ+ and BD+ had an intermediate-type; the morning-type was more frequent among participants under inpatient SUD treatment. SZ+ patients had the highest amount of sleeping hours, lowest arousal and highest drowsiness followed by BD+ and MDD+, respectively. These observed differences suggest that treatment for patients with dual disorders could include chronobiological strategies to help them synchronize patterns with the day-light cycle, since morning-type is associated with better outcomes and recovery.

The positive and negative sleep appraisal measure: Towards a clinical validation of sleep spectrum cognitions

BACKGROUND

Sleep disturbance is considered a transdiagnostic process due to high comorbidity with mental health difficulties. In particular, sleep disturbances are a feature of mood disorders. To advance transdiagnostic psychological interventions targeting sleep, the Positive and Negative Sleep Appraisal Measure (PANSAM) was developed. The PANSAM is a theory-driven measure based on an Integrative Cognitive Sleep Model and proposes that positive and negative sleep appraisals for excessively long and short sleep durations play a key role in the development of insomnia, hypersomnia, and reduced need for sleep. This study evaluated clinical validity of this new measure.

METHODS

Participants were those who met bipolar at risk criteria and bipolar diagnoses (bipolar spectrum group) (N = 22), major depressive disorder (unipolar depression group) (N = 18), and a nonclinical group (N = 22). To compare against previous insomnia and bipolar disorder relevant research, administered measures included the Dysfunctional Beliefs and Attitudes about Sleep Scale (DBAS) and the Hypomanic and Positive Predictions Inventory (HAPPI).

RESULTS

Analysis of variance (ANOVA) tests revealed that the clinical groups scored significantly higher on the PANSAM. The same was shown for the DBAS and HAPPI. Post hoc analyses showed that the PANSAM scale and subscales had significant correlations with all clinical measures. Effect sizes are reported due to sample size limitations.

CONCLUSION

This study has initially validated the PANSAM with clinical populations and highlighted its applicability to a transdiagnostic approach.

The association between sleep quality and attenuated psychotic symptoms

AIM

To determine if poor sleep makes a unique contribution in predicting the likelihood of experiencing six or more attenuated psychotic symptoms and associated distress, after examining and controlling for sociodemographic factors, depression and drug/alcohol use.

METHOD

An online survey was conducted using Amazon's online crowdsourcing service Mechanical Turk (MTurk). The sample was 1013 adults (18 to 36 years) from the general population in the United States. The survey consisted of the Prodromal Questionnaire 16 (PQ-16), the Pittsburgh Sleep Quality Index, the Patient Health Questionnaire 9, the Drug Abuse Screening Test 10 and the Alcohol Use Disorders Identification Test. Regression analyses were performed with the PQ-16 as the dependent variable, and sleep quality as the predictor variable, holding constant sociodemographic variables, depression, and alcohol/drug abuse.

RESULTS

37% of the sample endorsed six or more PQ-16 items, which may be suggestive of an at-risk mental state, with sleep disturbance significantly increasing the likelihood (Odds ratio 2.09 < .001) of endorsing six or more PQ-16 items. After controlling for sociodemographic variables, depression and drug/alcohol abuse, poor sleep quality made a unique contribution of 5.8% of the variance accounted for in level of distress experienced by attenuated psychotic symptoms.

CONCLUSION

Effective treatment of sleep disturbance may reduce the likelihood ofexperiencing attenuated psychotic symptoms and associated distress.

Sleep disturbances and the At Risk Mental State: A systematic review and meta-analysis

AIMS

To synthesise and investigate how sleep disturbances relate to psychotic symptoms, functioning and Quality of Life (QoL) in At Risk Mental State (ARMS) youth.

METHOD

A comprehensive search of six databases (MEDLINE, PsycINFO, Embase, CINAHL, Web of Science and CENTRAL) was conducted. Eligible studies provided data on sleep disturbances or disorders in ARMS patients.

RESULTS

Sixteen studies met the inclusion criteria (n = 1962 ARMS patients) including 7 cross-sectional studies, 2 RCT's and 7 cohort studies. Narrative synthesis revealed that self-reported sleep (e.g., general disturbances, fragmented night time sleep and nightmares) was poorer among ARMS patients compared to healthy controls. In the limited studies (n = 4) including objective measurements of sleep disturbances, ARMS patients experienced higher levels of movement during sleep, more daytime naps and increased sleep latency compared to controls. Furthermore, sleep disturbances were associated with attenuated psychotic symptoms and functional outcomes cross-sectionally and longitudinally. Only one study investigated the relationship between sleep and QoL. The exploratory meta-analysis revealed a significant difference in self-reported sleep disturbances measured by the PSQI (mean difference in score: 3.30 (95% CI 1.87, 4.74), p < 0.00001) and SIPS (mean difference in score: 1.58 (95% CI 0.80, 2.35), p < 0.00001) of ARMS patients compared to control groups.

CONCLUSIONS

ARMS individuals report impaired sleep quality and reduced sleep quantity compared to healthy controls. However, further research is needed to explore the longitudinal relationship between sleep disruptions and QoL in early psychosis. Significant variations in how sleep is measured across studies highlight a need to assess disturbances to sleep using robust and consistent approaches in this patient group.

Prolonged functional cerebral asymmetry as a consequence of dysfunctional parvocellular paraventricular hypothalamic nucleus signaling: An integrative model for the pathophysiology of bipolar disorder

Approximately 45 million people worldwide are diagnosed with bipolar disorder (BD). While there are many known risk factors and models of the pathologic processes influencing BD, the exact neurologic underpinnings of BD are unknown. We attempt to integrate the existing literature and create a unifying hypothesis regarding the pathophysiology of BD with the hope that a concrete model may potentially facilitate more specific diagnosis, prevention, and treatment of BD in the future. We hypothesize that dysfunctional signaling from the parvocellular neurons of the paraventricular hypothalamic nucleus (PVN) results in the clinical presentation of BD. Functional damage to this nucleus and its signaling pathways may be mediated by myriad factors (e.g. immune dysregulation and auto-immune processes, polygenetic variation, dysfunctional interhemispheric connections, and impaired or overactivated hypothalamic axes) which could help explain the wide variety of clinical presentations along the BD spectrum. The neurons of the PVN regulate ultradian rhythms, which are observed in cyclic variations in healthy individuals, and mediate changes in functional hemispheric lateralization. Theoretically, dysfunctional PVN signaling results in prolonged functional hemispheric dominance. In this model, prolonged right hemispheric dominance leads to depressive symptoms, whereas left hemispheric dominance correlated to the clinical picture of mania. Subsequently, physiologic processes that increase signaling through the PVN (hypothalamic-pituitaryadrenal axis, hypothalamic- pituitary-gonadal axis, and hypothalamic-pituitary-thyroid axis activity, suprachiasmatic nucleus pathways) as well as, neuro-endocrine induced excito-toxicity, auto-immune and inflammatory flairs may induce mood episodes in susceptible individuals. Potentially, ultradian rhythms slowing with age, in combination with changes in hypothalamic axes and maturation of neural circuitry, accounts for BD clinically presenting more frequently in young adulthood than later in life.

Evidence Base Update on Assessing Sleep in Youth

BACKGROUND

Sleep is vital to youth well-being and when it becomes disturbed - whether due to environmental or individual factors - mental and physical health suffer. Sleep problems can also be a symptom of underlying mental health disorders. Assessing different components of sleep, including quality and hygiene, can be useful both for identifying mental health problems and for measuring changes in well-being over time. However, there are dozens of sleep-related measures for youth and it can be difficult to determine which to select for a specific research or clinical purpose. The goal of this review was to identify sleep-related measures for clinical and/or research use in youth mental health settings, and to update the evidence base on this topic.

METHOD

We generated a list of candidate measures based on other reviews and searched in PubMed and PsycINFO using the terms "sleep" AND (measure OR assessment OR questionnaire) AND (psychometric OR reliability OR validity). Search results were limited to studies about children and adolescents (aged 2-17) published in English. Additional criteria for inclusion were that there had to be at least three publications reporting on the measure psychometrics in community or mental health populations. Sleep measures meeting these criteria were evaluated using the criteria set by De Los Reyes and Langer (2018).

RESULTS

Twenty-six measures, across four domains of sleep - insomnia, sleep hygiene, sleepiness, sleep quality - met inclusion criteria. Each measure had at least adequate clinical utility. No measure(s) emerged as superior across psychometric domains.

CONCLUSION

Clinicians and researchers must evaluate sleep measures for each use case, as the intended purpose will dictate which measure is best. Future research is necessary to evaluate measure performance in transdiagnostic mental health populations, including youth with serious mental illness.

Circadian activity rhythms and fatigue of adolescent cancer survivors and healthy controls: a pilot study

STUDY OBJECTIVES

The primary objective of this study was to compare circadian activity rhythms (CARs) of adolescents within 5 years of completing cancer treatment (survivors) with that of healthy adolescent controls. Secondary objectives were to explore differences in the relationship of CARs and fatigue between survivors and controls and between early survivors (<12 months posttreatment) and late survivors (≥12 months posttreatment).

METHODS

Twenty-nine survivors and 30 controls, aged 13-18 years, participated in this prospective, descriptive pilot study. Adolescents and their parents completed a baseline measure of adolescents' fatigue. Adolescents wore a wrist actigraph continuously for 7 days and concurrently kept a sleep diary. Activity data recorded by actigraphy were fitted to an extended cosine model to calculate six CAR variables: acrophase, amplitude, midline estimating statistic of rhythm (MESOR), up-MESOR, down-MESOR, and F-statistic. Linear mixed models explored the relationship between CARs and fatigue.

RESULTS

There were no group differences on CAR or fatigue measures. Among survivors, earlier down-MESOR was associated with greater parent-reported fatigue (P = .020), and earlier acrophase (P = .023) and up-MESOR (P = .025) were associated with greater adolescent-reported fatigue. Significant CAR-by-time posttreatment interaction effects were found on fatigue between early and late survivors. Among controls, greater parent-reported fatigue was associated with greater MESOR (P = .0495).

CONCLUSIONS

Survivors within the first 5 years posttreatment were similar to controls in CARs and fatigue, suggesting robust recovery of circadian rhythms posttreatment. Different CAR characteristics were associated with fatigue in survivors and controls. Time posttreatment influenced the relationship between CARs and fatigue for survivors, with significant effects only for early survivors.

Disrupted Sleep and Circadian Rhythms in Schizophrenia and Their Interaction With Dopamine Signaling

Sleep and circadian rhythm disruption (SCRD) is a common feature of schizophrenia, and is associated with symptom severity and patient quality of life. It is commonly manifested as disturbances to the sleep/wake cycle, with sleep abnormalities occurring in up to 80% of patients, making it one of the most common symptoms of this disorder. Severe circadian misalignment has also been reported, including non-24 h periods and phase advances and delays. In parallel, there are alterations to physiological circadian parameters such as body temperature and rhythmic hormone production. At the molecular level, alterations in the rhythmic expression of core clock genes indicate a dysfunctional circadian clock. Furthermore, genetic association studies have demonstrated that mutations in several clock genes are associated with a higher risk of schizophrenia. Collectively, the evidence strongly suggests that sleep and circadian disruption is not only a symptom of schizophrenia but also plays an important causal role in this disorder. The alterations in dopamine signaling that occur in schizophrenia are likely to be central to this role. Dopamine is well-documented to be involved in the regulation of the sleep/wake cycle, in which it acts to promote wakefulness, such that elevated dopamine levels can disturb sleep. There is also evidence for the influence of dopamine on the circadian clock, such as through entrainment of the master clock in the suprachiasmatic nuclei (SCN), and dopamine signaling itself is under circadian control. Therefore dopamine is closely linked with sleep and the circadian system; it appears that they have a complex, bidirectional relationship in the pathogenesis of schizophrenia, such that disturbances to one exacerbate abnormalities in the other. This review will provide an overview of the evidence for a role of SCRD in schizophrenia, and examine the interplay of this with altered dopamine signaling. We will assess the evidence to suggest common underlying mechanisms in the regulation of sleep/circadian rhythms and the pathophysiology of schizophrenia. Improvements in sleep are associated with improvements in symptoms, along with quality of life measures such as cognitive ability and employability. Therefore the circadian system holds valuable potential as a new therapeutic target for this disorder.

Sleep disturbances in youth at-risk for serious mental illness

AIM

To investigate sleep behaviours of youth at-risk for serious mental illness (SMI).

METHODS

This study included 243 youth, ages 12 to 25:42 healthy controls, 41 asymptomatic youth at-risk for mental illness (stage 0); 53 help-seeking youth experiencing distress (stage 1a) and 107 youth with attenuated syndromes (stage 1b). The Pittsburgh Sleep Quality Index was used to assess sleep dysfunction.

RESULTS

Stage 1b individuals indicated the greatest deficit in global sleep dysfunction (F = 26.18, P < .0001). Stages 1a and 1b reported significantly worse subjective sleep quality, a longer sleep latency, increased use of sleep medications as well as greater daytime dysfunction compared to the asymptomatic groups.

CONCLUSION

Research investigating sleep behaviours of youth considered to be at-risk for SMI is limited. This study provides early evidence that sleep disturbances are worse for individuals considered to be at higher risk of illness development.

Insomnia and suicidal ideation in nonaffective psychosis

Study Objectives

Insomnia is a common symptom in the clinical course of schizophrenia. There is a robust association between insomnia and suicidality in other psychiatric disorders. Two previous studies found associations between insomnia and suicide attempt or completed suicide in patients with schizophrenia. We hypothesized that greater insomnia would be associated with greater levels of suicidal ideation in patients with schizophrenia and other nonaffective psychoses.

Methods

We recruited 108 inpatients and outpatients age 18-65 between July 2010 and July 2016 with DSM-IV nonaffective psychosis (schizophrenia, schizoaffective disorder, or schizophreniform disorder). We investigated relationships between current insomnia (Insomnia Severity Index [ISI]), suicidal ideation over the past week, and lifetime history of suicide attempt (Beck Scale for Suicide Ideation [BSS]) in regression analyses.

Results

After controlling for potential confounders, insomnia was a significant indicator of suicidal ideation (β = 0.27, p = 0.032). Insomnia was also a significant indicator of a high BSS score (≥16; OR = 1.14, 95% CI: 1.01-1.28, p = 0.029). Furthermore, participants with severe insomnia were almost 15 times more likely to have a lifetime history suicide attempt than participants without current insomnia (OR = 14.8, 95% CI: 1.4-157, p = 0.025). Insomnia was also an indicator of greater PANSS total (β = 0.33, p = 0.001), positive subscale (β = 0.32, p = 0.002), and general subscale (β = 0.40, p < 0.001) scores.

Conclusions

Insomnia is associated with suicidal ideation, lifetime suicide attempt, and greater psychopathology in patients with schizophrenia. Our findings suggest that formal assessment of insomnia may be germane to the clinical care of patients with schizophrenia as a marker of suicide risk and symptom severity.

The development of a theoretically derived measure exploring extreme appraisals of sleep in bipolar disorder: a Delphi study with professionals

BACKGROUND

Sleep and mood are known to be linked and this is particularly evident in people with a diagnosis of bipolar disorder (BD). It has been proposed that psychological interventions improving sleep can be a pathway for improving mood. In order for a psychological sleep intervention to be appropriate, the common cognitive processes maintaining the range of sleep disturbances need to be investigated.

AIM

This study aimed to explore and identify expert consensus on positive and negative sleep appraisals in the context of low and high mood states, using the Integrative Cognitive Model as a theoretical guide.

METHOD

A Delphi approach was utilized to allow clinical and research professionals, with experience in the field of BD, to be anonymously consulted about their views on sleep appraisals. These experts were invited to participate in up to three rounds of producing and rating statements that represented positive and negative sleep appraisals.

RESULTS

A total of 38 statements were developed and rated, resulting in a final list of 19 statements that were rated as 'essential' or 'important' by >80% of the participants. These statements represent the full range of extreme sleep appraisals this study had set out to explore, confirming the importance of better understanding and identifying positive and negative sleep cognitions in the context of high and low mood.

CONCLUSION

The statements reviewed in this study will be used to inform the development of a sleep cognition measure that may be useful in cognitive therapy addressing sleep disturbances experienced along the bipolar spectrum.

The genetics of bipolar disorder

Bipolar disorder (BD) is one of the most heritable mental illnesses, but the elucidation of its genetic basis has proven to be a very challenging endeavor. Genome-Wide Association Studies (GWAS) have transformed our understanding of BD, providing the first reproducible evidence of specific genetic markers and a highly polygenic architecture that overlaps with that of schizophrenia, major depression, and other disorders. Individual GWAS markers appear to confer little risk, but common variants together account for about 25% of the heritability of BD. A few higher-risk associations have also been identified, such as a rare copy number variant on chromosome 16p11.2. Large scale next-generation sequencing studies are actively searching for other alleles that confer substantial risk. As our understanding of the genetics of BD improves, there is growing optimism that some clear biological pathways will emerge, providing a basis for future studies aimed at molecular diagnosis and novel therapeutics.

Indicators of vulnerability associated with less healthy circadian rhythms in undergraduate medical interns

To evaluate the association between circadian health parameters and psychological and biological vulnerability, a cross-sectional study was conducted with 15 undergraduate medical interns using the Brief Resilience Scale, the Mini International Neuropsychiatric Interview, and an ambulatory circadian monitoring device. Circadian Health construct was confirmed by factor analysis. Vulnerability factors (history of depression and low resilience) were associated to lower circadian health of motor activity and temperature rhythms. The findings suggest that not only being depressed but also having had depressive episodes in the past, as well as having low resilience, are associated with chronodisruption, and may increase the risk for developing new episodes of depression.

Relationship between circadian activity rhythms and fatigue in hospitalized children with CNS cancers receiving high-dose chemotherapy

PURPOSE

Robust circadian rhythms are increasingly recognized as essential to good health. Adult cancer patients with dysregulated circadian activity rhythms (CAR) experience greater fatigue, lower responsiveness to chemotherapy, and shorter time to relapse. There is scant research describing circadian rhythms and associated outcomes in children with cancer. As part of a larger study examining whether a cognitive-behavioral intervention could preserve sleep in children and adolescents with central nervous system cancers hospitalized for high-dose chemotherapy (HDCT), this study aimed to compare CAR of these children to published values and to investigate the relationship between CAR and fatigue.

METHODS

Participants aged 4-19 years wore an actigraph throughout their hospitalization (5 days). From activity counts recorded by actigraphy, six CAR variables were calculated: amplitude, 24-h autocorrelation (r24), dichotomy index (I < O), interdaily stability (IS), intradaily variability (IV), and acrophase. Parent-reported child fatigue and child/adolescent self-reported fatigue measures were collected daily.

RESULTS

Thirty-three participants were included. Three CAR variables (amplitude, r24, and I < O) showed dysregulation compared to published values. Older age was significantly associated with later acrophase and greater dysregulation of all other CAR variables. Controlling for age, more dysregulated amplitude (p = 0.001), r24 (p = 0.003), IS (p = 0.017), and IV (p = 0.001) were associated with higher parent-reported fatigue; more dysregulated IV (p = 0.003) was associated with higher child-reported fatigue.

CONCLUSIONS

Participants demonstrated dysregulated CAR during hospitalization for HDCT. Greater dysregulation was associated with greater fatigue. Research on circadian dysregulation and its relationship to health-related outcomes in children with cancer, and interventions to support circadian rhythmicity, is urgently needed.

Motor activity patterns in acute schizophrenia and other psychotic disorders can be differentiated from bipolar mania and unipolar depression

The purpose of this study was to compare 24-h motor activity patterns between and within three groups of acutely admitted inpatients with schizophrenia and psychotic disorders (n = 28), bipolar mania (n = 18) and motor-retarded unipolar depression (n = 25) and one group of non-hospitalized healthy individuals (n = 28). Motor activity was measured by wrist actigraphy, and analytical approaches using linear and non-linear variability and irregularity measures were undertaken. In between-group comparisons, the schizophrenia group showed more irregular activity patterns than depression cases and healthy individuals. The schizophrenia and mania cases were clinically similar with respect to high prevalence of psychotic symptoms. Although they could not be separated by a formal statistical test, the schizophrenia cases showed more normal amplitudes in morning to evening mean activity and activity variability. Schizophrenia constituted an independent entity in terms of motor activation that could be distinguished from the other diagnostic groups of psychotic and non-psychotic affective disorders. Despite limitations such as small subgroups, short recordings and confounding effects of medication/hospitalization, these results suggest that detailed temporal analysis of motor activity patterns can identify similarities and differences between prevalent functional psychiatric disorders. For this purpose, irregularity measures seem particularly useful to characterize psychotic symptoms and should be explored in larger samples with longer-term recordings, while searching for underlying mechanisms of motor activity disturbances.

Chronotype and Mental Health: Recent Advances

PURPOSE OF REVIEW

Evening chronotype is increasingly recognized as a correlate of, and perhaps a contributor to, mental illness. The current review evaluates recent evidence for the association between chronotype and mental illness and putative mechanisms underlying the association, while highlighting methodological advances and areas of research that are relatively under-examined in the literature.

RECENT FINDINGS

While evening chronotype is most consistently associated with severity of mood disorder symptoms, emerging evidence implicates evening chronotype as a transdiagnostic correlate of substance use severity, anxiety symptoms, attentional difficulties, and maladaptive behaviors such as aggression. Longitudinal studies point to the possibility that evening chronotype precedes problematic substance use, depression, and anxiety. Neural processes related to reward and affective regulation may underlie associations between evening chronotype and illness. The literature on chronotype and mental illness has evolved to (1) include associations with a broader range of psychiatric symptom profiles; (2) explore underlying mechanisms; and (3) expand on earlier research using objective measures and more sophisticated study designs. In addition to further mechanistic research, additional work is needed to examine the stability and key subcomponents of the chronotype construct, as well as more attention to pediatric and special populations. This research is needed to clarify the chronotype-mental health relationship, and to identify how, when, and what aspects of chronotype can be targeted via therapeutic interventions.

Clinical correlates of hypothalamic-pituitary-adrenal axis measures in individuals at risk for psychosis and with first-episode psychosis

Hypothalamic-pituitary-adrenal (HPA) axis alterations in at-risk mental states (ARMS) resemble those observed in established psychosis but are less consistent. We aimed to explore HPA axis abnormalities in both first-episode psychosis (FEP) and ARMS patients, while controlling for psychopathological symptoms. We studied 21 ARMS, 34 FEP patients and 34 healthy subjects. Clinical assessment included psychopathological symptoms (positive, negative, disorganized, excited and depressive symptoms) and stress measures. Saliva cortisol levels were determined at awakening, 30' and 60' post-awakening, 10:00 h, 23:00 h and 10:00 h on the day after the administration of 0.25 mg of dexamethasone, which occurred at 23:00 h. Three HPA axis measures were calculated: cortisol awakening response (CAR), cortisol diurnal slope and cortisol suppression ratio of the dexamethasone suppression test (DST). There were no significant differences between groups in HPA axis measures. However, when exploring the relationship between HPA axis measures and psychopathological symptoms, in ARMS subjects (but not FEP patients), a flatter cortisol slope was associated with more prominent negative symptoms, whereas a blunted CAR was associated with excited symptoms. Although no significant differences in HPA axis measures were found between diagnostic groups, subtle abnormalities in the CAR or circadian cortisol rhythmicity might be important for the phenotype of ARMS individuals.

Sleep, circadian rhythms, and schizophrenia: where we are and where we need to go

PURPOSE OF REVIEW

The review is designed to give an overview of the latest developments in research exploring the relationship between sleep and psychosis, with particular attention paid to the evidence for a causal relationship between the two.

RECENT FINDINGS

The most interesting avenues currently in pursuit are focused upon sleep spindle deficits which may hallmark an endophenotype; explorations of the continuum of psychotic experiences, and experimental manipulations to explore the evidence for bidirectional causality; inflammatory markers, psychosis and sleep disturbances and finally, treatment approaches for sleep in psychosis and the subsequent impact on positive experiences.

SUMMARY

Globally, large surveys and tightly controlled sleep deprivation or manipulation experiments provide good evidence for a cause-and-effect relationship between sleep and subclinical psychotic experiences. The evidence for cause-and-effect using a interventionist-causal model is more ambiguous; it would appear treating insomnia improves psychotic experiences in an insomnia cohort but not in a cohort with schizophrenia. This advocates the necessity for mechanism-driven research with dimensional approaches and in depth phenotyping of circadian clock-driven processes and sleep regulating functions. Such an approach would lead to greater insight into the dynamics of sleep changes in healthy and acute psychosis brain states.

The interaction between subclinical psychotic experiences, insomnia and objective measures of sleep

Investigations into schizophrenia have revealed a high incidence of comorbidity with disturbed sleep and circadian timing. Acknowledging this comorbidity on a dimensional level, we tested prospectively whether subclinical psychotic symptoms are more prevalent in individuals with insomnia. An insomnia group (n=21) and controls (n=22) were recruited on their subjective sleep quality, recorded actigraphically for 3weeks and assessed for psychotic-like experiences with The Prodromal Questionnaire-16. Using multivariate Poisson regression analyses, we found that objective and subjective sleep measures interact to predict the highest risk for psychotic experiences. Objective measures of sleep and statistical modelling are rarely used in either clinical trials or practice for schizophrenia, yet this study highlights their value in these areas.

Self-reported sleep disturbances associated with procedural learning impairment in adolescents at ultra-high risk for psychosis

Sleep disturbance contributes to impaired procedural learning in schizophrenia, yet little is known about this relationship prior to psychosis onset. Adolescents at ultra high-risk (UHR; N=62) for psychosis completed the Pittsburgh Sleep Quality Index (PSQI) and a procedural learning task (Pursuit Rotor). Increased self-reported problems with sleep latency, efficiency, and quality were associated with impaired procedural learning rate. Further, within-sample comparisons revealed that UHR youth reporting better sleep displayed a steeper learning curve than those with poorer sleep. Sleep disturbances appear to contribute to cognitive/motor deficits in the UHR period and may play a role in psychosis etiology.

BDNF and BMI effects on brain structures of bipolar offspring: results from the global mood and brain science initiative

OBJECTIVE

To compare brain-derived neurotrophic factor (BDNF) levels between offspring of individuals with bipolar disorders (BD) and healthy controls (HCs) and investigate the effects of BDNF levels and body mass index (BMI) on brain structures.

METHOD

Sixty-seven bipolar offspring and 45 HCs were included (ages 8-28). Structural images were acquired using 3.0 Tesla magnetic resonance imaging. Serum BDNF levels were measured using enzyme-linked immunosorbent assay. Multivariate and univariate analyses of covariance were conducted.

RESULTS

Significantly higher BDNF levels were observed among bipolar offspring, relative to HCs (P > 0.025). Offspring status moderated the association between BDNF and BMI (F₁ =4.636, P = 0.034). After adjustment for relevant covariates, there was a trend for a significant interaction of group and BDNF on neuroimaging parameters (Wilks'λ F_56,94 =1.463, P = 0.052), with significant effects on cerebellar white matter and superior and middle frontal regions. Brain volume and BDNF were positively correlated among HCs and negatively correlated among bipolar offspring. Interactions between BDNF and BMI on brain volumes were non-significant among HCs (Wilks'λ F_28,2 =2.229, P = 0.357), but significant among bipolar offspring (Wilks'λ F_28,12 =2.899, P = 0.028).

CONCLUSION

Offspring status and BMI moderate the association between BDNF levels and brain structures among bipolar offspring, underscoring BDNF regulation and overweight/obesity as key moderators of BD pathogenesis.

Adolescents at clinical-high risk for psychosis: Circadian rhythm disturbances predict worsened prognosis at 1-year follow-up

BACKGROUND

Individuals with psychotic disorders experience disruptions to both the sleep and circadian components of the sleep/wake cycle. Recent evidence has supported a role of sleep disturbances in emerging psychosis. However, less is known about how circadian rhythm disruptions may relate to psychosis symptoms and prognosis for adolescents with clinical high-risk (CHR) syndromes. The present study examines circadian rest/activity rhythms in CHR and healthy control (HC) youth to clarify the relationships among circadian rhythm disturbance, psychosis symptoms, psychosocial functioning, and the longitudinal course of illness.

METHODS

Thirty-four CHR and 32 HC participants were administered a baseline evaluation, which included clinical interviews, 5days of actigraphy, and a sleep/activity diary. CHR (n=29) participants were re-administered clinical interviews at a 1-year follow-up assessment.

RESULTS

Relative to HC, CHR youth exhibited more fragmented circadian rhythms and later onset of nocturnal rest. Circadian disturbances (fragmented rhythms, low daily activity) were associated with increased psychotic symptom severity among CHR participants at baseline. Circadian disruptions (lower daily activity, rhythms that were more fragmented and/or desynchronized with the light/dark cycle) also predicted severity of psychosis symptoms and psychosocial impairment at 1-year follow-up among CHR youth.

CONCLUSIONS

Circadian rhythm disturbances may represent a potential vulnerability marker for emergence of psychosis, and thus, rest/activity rhythm stabilization has promise to inform early-identification and prevention/intervention strategies for CHR youth. Future studies with longer study designs are necessary to further examine circadian rhythms in the prodromal period and rates of conversion to psychosis among CHR teens.

Shorter leukocyte telomere length in patients at ultra high risk for psychosis

Telomere length attrition has been demonstrated in schizophrenia but not in individuals in ultra high risk (UHR) for psychosis. The present study aimed to compare the leukocyte telomere length (TL) between patients at UHR for psychosis and healthy controls (HC). Twenty-two participants with UHR and 88 HC were enrolled in this study. Telomere lengths were determined using a multiplex qPCR assay. After adjustment for age, sex, ethnicity, and education, patients in UHR, compared with HC groups, had shorter telomere length (RR: 0.929, p=0.031). Shorter leukocyte telomere length in UHR could represent early signs of accelerated aging in this population.

Circadian Rhythm Dysregulation in Bipolar Spectrum Disorders

PURPOSE OF REVIEW

We review recent evidence for circadian rhythm dysregulation in bipolar spectrum disorders (BSDs). We examine evidence for endogenous abnormalities in the biological clock and disruptions in the external entrainment of circadian rhythms in BSDs. We also address whether circadian dysregulation provides vulnerability to onset of BSD and evidence for a new integration of reward and circadian dysregulation in BSD.

RECENT FINDINGS

Relative circadian phase delay (e.g., later melatonin peak, evening chronotype) is associated with BSD, particularly in the depressive phase. More consistent evidence supports irregularity of social rhythms, sleep/wake and activity patterns, and disruptions of social rhythms by life events, as stable trait markers of BSD and potential vulnerabilities for BSD onset. Growing research supports an integrative reward/circadian model. Both endogenous abnormalities in the biological clock pacemaking function and disruptions in the external entrainment of circadian rhythms by physical and social cues are involved in BSDs. Circadian dysregulation may provide vulnerability to BSD onset.

Sleep-wake cycle phenotypes in young people with familial and non-familial mood disorders

OBJECTIVES

Converging evidence identifies that the offspring of parents with bipolar disorder (BD), individuals at clinical high risk of BD, and young people with recent onset BD may differ from other clinical cases or healthy controls in terms of sleep-wake profiles. However, it is possible that these differences may reflect current mental state, subtype of mood disorder, or familial traits. This study aimed to determine objective and subjective sleep-wake profiles in individuals aged 15-25 years with a current major depressive episode, in relation to familial traits.

METHODS

Frequency matching was employed to ensure that each individual with a confirmed family history of BD (FH+) could be compared to four controls who did not have a familial mood disorder (FH-). Pre-selected objective actigraphy and subjective Pittsburgh Sleep Quality Index (PSQI) ratings were compared using one-way analysis of variance (ANOVA) and applying the Benjamini-Hochberg (BH) correction for false discoveries.

RESULTS

The sample comprised 60 individuals with a mean age of 19 years. The FH+ (n=12) and FH- groups (n=48) differed on three key sleep parameters: mean sleep duration on week nights (P=.049), variability in waking after sleep onset (P=.038), and daily disturbances (PSQI dimension of sleep disturbance and daytime dysfunction; P=.01).

CONCLUSIONS

The sleep profiles we identified in this study, especially the daily disturbances phenotype, provide support for research into endophenotypes for BD. Also, the findings may offer the opportunity for more tailored, personalized interventions that target specific components of the sleep-wake cycle in individuals with a family history of BD.

Sleep and circadian alterations in people at risk for bipolar disorder: A systematic review

BACKGROUND

Sleep and circadian abnormalities have been mostly demonstrated in bipolar patients. However, it is not clear whether these alterations are present in population at high risk for bipolar disorder (BD), indicating a possible risk factor for this condition.

OBJECTIVE

This systematic review aims to define current evidence about sleep and rhythm alterations in people at risk for BD and to evaluate sleep and circadian disorders as risk factor for BD.

METHODS

The systematic review included all articles about the topic until February 2016. Two researchers performed an electronic search of PubMed and Cochrane Library. Keywords used were 'sleep' or 'rhythm' or 'circadian' AND 'bipolar disorder' or 'mania' or 'bipolar depression' AND 'high-risk' or 'risk'.

RESULTS

Thirty articles were analyzed (7451 participants at risk for BD). Sleep disturbances are frequent in studies using both subjective measures and actigraphy. High-risk individuals reported irregularity of sleep/wake times, poor sleep and circadian rhythm disruption. Poor sleep quality, nighttime awakenings, and inadequate sleep are possible predictive factors for BD. A unique study suggested that irregular rhythms increase risk of conversion. People at risk for BD showed high cortisol levels in different times of day. Studies about anatomopathology, melatonin levels, inflammatory cytokines and oxidative stress were not identified. The most important limitations were differences in sleep and rhythm measures, heterogeneity of study designs, and lack of consistency in the definition of population at risk.

CONCLUSION

Sleep and circadian disturbances are common in people at risk for BD. However, the pathophysiology of these alterations and the impact on BD onset are still unclear.

Peripheral immuno-inflammatory abnormalities in ultra-high risk of developing psychosis

BACKGROUND

Immuno-inflammatory imbalances have been documented in schizophrenia, but very little is known about the immunological changes prior to the onset of disease.

OBJECTIVE

This work aimed to compare serum levels of pro- and anti-inflammatory cytokines in young subjects at ultra-high risk (UHR) of developing psychosis with age- and sex-matched healthy controls.

METHODS

A total of 12 UHR and 16 age- and sex-matched healthy controls (HC) subjects were enrolled in this study. Clinical profile was assessed using the Comprehensive Assessment of At-Risk Mental States (CAARMS), Semi-Structured Clinical Interview for DSM-IV Axis-I (SCID-I) or Kiddie-SADS-Present and Lifetime Version (K-SADS-PL), and Global Assessment of Functioning (GAF) scale. Serum interleukin (IL)-2, IL-4, IL-6, IL-10, tumor necrosis factor (TNF)-α, IFN-γ, and IL-17 were measured by flow cytometry using the Th1/Th2/Th17 cytometric bead array.

RESULTS

Compared with the healthy control group, patients in UHR showed increased IL-6 levels (Z=-2.370, p=0.018) and decreased IL-17 levels in serum (Z=-1.959, p=0.050). Levels of IL-17 positively correlated to the values in GAF symptoms (rho=0.632, p=0.028).

CONCLUSION

Our results suggest that immunological imbalances could be present in the early stages of psychosis, including in at-risk stages. Future studies should replicate and expand these results.

Challenges and developments in research of the early stages of bipolar disorder

Recently, attention in the field of bipolar disorder (BD) has focused on prevention, including early detection and intervention, as these strategies have the potential to delay, lessen the severity, or even prevent full-blown episodes of BD. Although knowledge of the neurobiology of BD has advanced substantially in the last two decades, most research was conducted with chronic patients. The objective of this paper is to comprehensively review the literature regarding the early stages of BD, to explore recent discoveries on the neurobiology of these stages, and to discuss implications for research and clinical care. The following databases were searched: PubMed, PsycINFO, Cochrane Library, and SciELO. Articles published in English from inception to December 2015 were retrieved. Several research approaches were used, including examination of offspring studies, retrospective studies, prospective studies of clinical high-risk populations, and exploration of the progression after the first manic episode. Investigations with neuroimaging, cognition assessments, and biomarkers provide promising (although not definitive) evidence of alterations in the neural substrate during the at-risk stage. Research on BD should be expanded to encompass at-risk states and aligned with recent methodological progress in neuroscience.