A developmental model for similarities and dissimilarities between schizophrenia and bipolar disorder

Effective connectivity within a triple network brain system discriminates schizophrenia spectrum disorders from psychotic bipolar disorder at the single-subject level

OBJECTIVE

Schizophrenia spectrum disorders (SSD) and psychotic bipolar disorder share a number of genetic and neurobiological features, despite a divergence in clinical course and outcome trajectories. We studied the diagnostic classification potential that can be achieved on the basis of the structure and connectivity within a triple network system (the default mode, salience and central executive network) in patients with SSD and psychotic bipolar disorder.

METHODS

Directed static connectivity and its dynamic variance was estimated among 8 nodes of the three large-scale networks. Multivariate autoregressive models of deconvolved resting state functional magnetic resonance imaging time series were obtained from 57 patients (38 with SSD and 19 with bipolar disorder and psychosis). We used 2/3 of the patients for training and validation of the classifier and the remaining 1/3 as an independent hold-out test data for performance estimation.

RESULTS

A high level of discrimination between bipolar disorder with psychosis and SSD (combined balanced accuracy = 96.2%; class accuracies 100% for bipolar and 92.3% for SSD) was achieved when effective connectivity and morphometry of the triple network nodes was combined with symptom scores. Patients with SSD were discriminated from patients with bipolar disorder and psychosis as showing higher clinical severity of disorganization and higher variability in the effective connectivity between salience and executive networks.

CONCLUSIONS

Our results support the view that the study of network-level connectivity patterns can not only clarify the pathophysiology of SSD but also provide a measure of excellent clinical utility to identify discrete diagnostic/prognostic groups among individuals with psychosis.

Neurocognition in young offspring of individuals with bipolar disorder: The role of co-existing familial and clinical high-risk for bipolar disorder

Bipolar disorder (BD) is associated with cognitive dysfunction which has also been reported in offspring of individuals with BD (BDoff). However, it remains unclear whether cognitive underperformance in BDoff is associated with the presence of history of subclinical syndromes associated with risk for BD. To address this knowledge gap we assessed executive function, visual and verbal memory, working memory, processing speed and verbal fluency in 21 offspring with clinical high risk (CHR; BDoff+CHR), 54 offspring without CHR (BDoff-non-CHR), and 50 healthy individuals without familial risk of BD. BDoff underperformed compared to controls in most cognitive tasks. There was no significant neurocognitive difference between BDoff+CHR and BDoff-non-CHR except in the fluency/central executive domain (Cohen's d = 0.60, p = 0.03). Our results suggest that cognitive dysfunction in multiple domains is associated with familial predisposition to BD regardless of CHR status. On the other hand, abnormalities in central executive processes might be more pronounced in BDoff+CHR than BDoff-non-CHR. Further longitudinal studies investigating cognitive trajectory of BDoff and its interaction with the emergence of subclinical syndromes are needed to fully characterize the relationship between cognition and mood dysregulation in BD.

Risk of schizophrenia, schizoaffective, and bipolar disorders by migrant status, region of origin, and age-at-migration: a national cohort study of 1.8 million people

BACKGROUND

We assessed whether the risk of various psychotic disorders and non-psychotic bipolar disorder (including mania) varied by migrant status, a region of origin, or age-at-migration, hypothesizing that risk would only be elevated for psychotic disorders.

METHODS

We established a prospective cohort of 1 796 257 Swedish residents born between 1982 and 1996, followed from their 15th birthday, or immigration to Sweden after age 15, until diagnosis, emigration, death, or end of 2011. Cox proportional hazards models were used to model hazard ratios by migration-related factors, adjusted for covariates.

RESULTS

All psychotic disorders were elevated among migrants and their children compared with Swedish-born individuals, including schizophrenia and schizoaffective disorder (adjusted hazard ratio [aHR]migrants: 2.20, 95% CI 1.96-2.47; aHRchildren : 2.00, 95% CI 1.79-2.25), affective psychotic disorders (aHRmigrant1.42, 95% CI 1.25-1.63; aHRchildren: 1.22 95% CI 1.07-1.40), and other non-affective psychotic disorders (aHRmigrant: 1.97, 95% CI 1.81-2.14; aHRchildren: 1.68, 95% CI 1.54-1.83). For all psychotic disorders, risks were generally highest in migrants from Africa (i.e. aHRschizophrenia: 5.24, 95% CI 4.26-6.45) and elevated at most ages-of-migration. By contrast, risk of non-psychotic bipolar disorders was lower for migrants (aHR: 0.58, 95% CI 0.52-0.64) overall, and across all ages-of-migration except infancy (aHR: 1.20; 95% CI 1.01-1.42), while risk for their children was similar to the Swedish-born population (aHR: 1.00, 95% CI 0.93-1.08).

CONCLUSIONS

Increased risk of psychiatric disorders associated with migration and minority status may be specific to psychotic disorders, with exact risk dependent on the region of origin.

The Association Between Familial Risk and Brain Abnormalities Is Disease Specific: An ENIGMA-Relatives Study of Schizophrenia and Bipolar Disorder

BACKGROUND

Schizophrenia and bipolar disorder share genetic liability, and some structural brain abnormalities are common to both conditions. First-degree relatives of patients with schizophrenia (FDRs-SZ) show similar brain abnormalities to patients, albeit with smaller effect sizes. Imaging findings in first-degree relatives of patients with bipolar disorder (FDRs-BD) have been inconsistent in the past, but recent studies report regionally greater volumes compared with control subjects.

METHODS

We performed a meta-analysis of global and subcortical brain measures of 6008 individuals (1228 FDRs-SZ, 852 FDRs-BD, 2246 control subjects, 1016 patients with schizophrenia, 666 patients with bipolar disorder) from 34 schizophrenia and/or bipolar disorder family cohorts with standardized methods. Analyses were repeated with a correction for intracranial volume (ICV) and for the presence of any psychopathology in the relatives and control subjects.

RESULTS

FDRs-BD had significantly larger ICV (d = +0.16, q < .05 corrected), whereas FDRs-SZ showed smaller thalamic volumes than control subjects (d = -0.12, q < .05 corrected). ICV explained the enlargements in the brain measures in FDRs-BD. In FDRs-SZ, after correction for ICV, total brain, cortical gray matter, cerebral white matter, cerebellar gray and white matter, and thalamus volumes were significantly smaller; the cortex was thinner (d < -0.09, q < .05 corrected); and third ventricle was larger (d = +0.15, q < .05 corrected). The findings were not explained by psychopathology in the relatives or control subjects.

CONCLUSIONS

Despite shared genetic liability, FDRs-SZ and FDRs-BD show a differential pattern of structural brain abnormalities, specifically a divergent effect in ICV. This may imply that the neurodevelopmental trajectories leading to brain anomalies in schizophrenia or bipolar disorder are distinct.

M. Staging of Schizophrenia With the Use of PANSS: An International Multi-Center Study

INTRODUCTION

A specific clinically relevant staging model for schizophrenia has not yet been developed. The aim of the current study was to evaluate the factor structure of the PANSS and develop such a staging method.

METHODS

Twenty-nine centers from 25 countries contributed 2358 patients aged 37.21 ± 11.87 years with schizophrenia. Analysis of covariance, Exploratory Factor Analysis, Discriminant Function Analysis, and inspection of resultant plots were performed.

RESULTS

Exploratory Factor Analysis returned 5 factors explaining 59% of the variance (positive, negative, excitement/hostility, depression/anxiety, and neurocognition). The staging model included 4 main stages with substages that were predominantly characterized by a single domain of symptoms (stage 1: positive; stages 2a and 2b: excitement/hostility; stage 3a and 3b: depression/anxiety; stage 4a and 4b: neurocognition). There were no differences between sexes. The Discriminant Function Analysis developed an algorithm that correctly classified >85% of patients.

DISCUSSION

This study elaborates a 5-factor solution and a clinical staging method for patients with schizophrenia. It is the largest study to address these issues among patients who are more likely to remain affiliated with mental health services for prolonged periods of time.

Horizontal and vertical integrative analysis methods for mental disorders omics data

In recent biomedical studies, omics profiling has been extensively conducted on various types of mental disorders. In most of the existing analyses, a single type of mental disorder and a single type of omics measurement are analyzed. In the study of other complex diseases, integrative analysis, both vertical and horizontal integration, has been conducted and shown to bring significantly new insights into disease etiology, progression, biomarkers, and treatment. In this article, we showcase the applicability of integrative analysis to mental disorders. In particular, the horizontal integration of bipolar disorder and schizophrenia and the vertical integration of gene expression and copy number variation data are conducted. The analysis is based on the sparse principal component analysis, penalization, and other advanced statistical techniques. In data analysis, integration leads to biologically sensible findings, including the disease-related gene expressions, copy number variations, and their associations, which differ from the “benchmark” analysis. Overall, this study suggests the potential of integrative analysis in mental disorder research.

Clinical and demographic differences between patients with manic, depressive and schizophrenia-spectrum psychoses presenting to Early Intervention Services in London

AIM

To investigate the relationship between the presenting clinical and demographic characteristics in first-episode psychosis (FEP) patients with their clinical diagnostic grouping 1 year later.

METHODS

Data from 1014 first-presentation psychosis patients from seven London-based Early Intervention Services were extracted from the MiData audit database. Associations between clinical and demographic measures at presentation and clinical diagnosis made at 1 year were assessed with analysis of variance (ANOVA) and Chi-square tests.

RESULTS

The sample comprised 76% of patients with schizophrenia-spectrum diagnoses, 9% with manic psychoses (MP) and 6% with depressive psychoses. Compared to the other 2 groups, patients who were diagnosed as having MP were younger, with higher education and shorter duration of untreated psychosis, and had higher Young Mania Rating Scale scores at presentation and lower Positive and Negative Syndrome Scale (PANSS) negative scores. Patients diagnosed at 1 year as having depressive psychosis were older and more likely to be white, with the lowest PANSS positive scores at baseline. Patients diagnosed at 1 year as having schizophrenia spectrum diagnoses were more likely to be males. Patients in the 3 diagnostic subgroups of psychosis differed on both clinical and demographic characteristics at presentation.

CONCLUSIONS

There were significant clinical and demographic differences at presentation between FEP patients who received different clinical diagnoses at 1 year. Future work should determine the extent to which these differences can be used to guide clinical care.

Exploring shared genetic bases and causal relationships of schizophrenia and bipolar disorder with 28 cardiovascular and metabolic traits

BACKGROUND

Cardiovascular diseases represent a major health issue in patients with schizophrenia (SCZ) and bipolar disorder (BD), but the exact nature of cardiometabolic (CM) abnormalities involved and the underlying mechanisms remain unclear. Psychiatric medications are known risk factors, but it is unclear whether there is a connection between the disorders (SCZ/BD) themselves and CM abnormalities.

METHODS

Using polygenic risk scores and linkage disequilibrium score regression, we investigated the shared genetic bases of SCZ and BD with 28 CM traits. We performed Mendelian randomization (MR) to elucidate causal relationships between the two groups of disorders. The analysis was based on large-scale meta-analyses of genome-wide association studies. We also identified the potential shared genetic variants and inferred the pathways involved.

RESULTS

We found tentative polygenic associations of SCZ with glucose metabolism abnormalities, adverse adipokine profiles, increased waist-to-hip ratio and visceral adiposity (false discovery rate or FDR&lt;0.05). However, there was an inverse association with body mass index. For BD, we observed several polygenic associations with favorable CM profiles at FDR&lt;0.05. MR analysis showed that SCZ may be causally linked to raised triglyceride and that lower fasting glucose may be linked to BD. We also identified numerous single nucleotide polymorphisms and pathways shared between SCZ/BD with CM traits, some of which are related to inflammation or the immune system.

CONCLUSIONS

Our findings suggest that SCZ patients may be genetically predisposed to several CM abnormalities independent of medication side effects. On the other hand, CM abnormalities in BD may be more likely to be secondary. However, the findings require further validation.

Transdiagnostic dimensions of psychopathology at first episode psychosis: findings from the multinational EU-GEI study

BACKGROUND

The value of the nosological distinction between non-affective and affective psychosis has frequently been challenged. We aimed to investigate the transdiagnostic dimensional structure and associated characteristics of psychopathology at First Episode Psychosis (FEP). Regardless of diagnostic categories, we expected that positive symptoms occurred more frequently in ethnic minority groups and in more densely populated environments, and that negative symptoms were associated with indices of neurodevelopmental impairment.

METHOD

This study included 2182 FEP individuals recruited across six countries, as part of the EUropean network of national schizophrenia networks studying Gene-Environment Interactions (EU-GEI) study. Symptom ratings were analysed using multidimensional item response modelling in Mplus to estimate five theory-based models of psychosis. We used multiple regression models to examine demographic and context factors associated with symptom dimensions.

RESULTS

A bifactor model, composed of one general factor and five specific dimensions of positive, negative, disorganization, manic and depressive symptoms, best-represented associations among ratings of psychotic symptoms. Positive symptoms were more common in ethnic minority groups. Urbanicity was associated with a higher score on the general factor. Men presented with more negative and less depressive symptoms than women. Early age-at-first-contact with psychiatric services was associated with higher scores on negative, disorganized, and manic symptom dimensions.

CONCLUSIONS

Our results suggest that the bifactor model of psychopathology holds across diagnostic categories of non-affective and affective psychosis at FEP, and demographic and context determinants map onto general and specific symptom dimensions. These findings have implications for tailoring symptom-specific treatments and inform research into the mood-psychosis spectrum.

Medication Adherence Using Electronic Monitoring in Severe Psychiatric Illness: 4 and 24 Weeks after Discharge

Objective

The purpose of this study was to examine post-hospitalization outpatient drug adherence in patients with severe psychiatric illness, including bipolar disorder and schizophrenia, and to investigate factors associated with drug adherence.

Methods

Eighty-one patients diagnosed with schizophrenia or bipolar disorder who were hospitalized due to aggravation of psychiatric symptoms were monitored. At hospitalization, we conducted clinical assessments such as the Clinical Global Impression-Severity, Drug Attitude Inventory, Contour Drawing Rating Scale, Multidimensional Scale of Perceived Social Support scale, and patients’ demographic factors. We measured drug adherence using the Medication Event Monitoring System (MEMS), pill count, and patients’ self-report upon out-patients visits, 4 and 24 weeks after discharge.

Results

The mean values of the various measures of adherence were as follows: MEMS (4 weeks) 84.8%, pill count (4 weeks) 94.6%, self-report (4 weeks) 92.6%, MEMS (24 weeks) 81.6%, pill count (24 weeks) 90.6%, and self-report (24 weeks) 93.6%. The adherence agreement between MEMS, pill count, and self-report was moderate (4 weeks intra-class correlation [ICC]=0.54, 24 weeks ICC=0.52). Non-adherence (MEMS ≤0.08) was observed in 26.4% of the patients at 4 weeks and 37.7% at 24 weeks. There was a negative correlation between drug adherence assessed 4 weeks after discharge and Contour Drawing Rating Scale difference score (r=−0.282, p<0.05). A positive correlation was found between drug adherence assessed 24 weeks after discharge and Drug Attitude Inventory (r=0.383, p<0.01).

Conclusion

Patients’ attitude towards their medication and their degree of physical dissatisfaction influenced post-hospitalization drug adherence in severe psychiatric patients.

Handwriting movements for assessment of motor symptoms in schizophrenia spectrum disorders and bipolar disorder

The main aim of the present study was to explore the value of several measures of handwriting in the study of motor abnormalities in patients with bipolar or psychotic disorders. 54 adult participants with a schizophrenia spectrum disorder or bipolar disorder and 44 matched healthy controls, participated in the study. Participants were asked to copy a handwriting pattern consisting of four loops, with an inking pen on a digitizing tablet. We collected a number of classical, non-linear and geometrical measures of handwriting. The handwriting of patients was characterized by a significant decrease in velocity and acceleration and an increase in the length, disfluency and pressure with respect to controls. Concerning non-linear measures, we found significant differences between patients and controls in the Sample Entropy of velocity and pressure, Lempel-Ziv of velocity and pressure, and Higuchi Fractal Dimension of pressure. Finally, Lacunarity, a measure of geometrical heterogeneity, was significantly greater in handwriting patterns from patients than from controls. We did not find differences in any handwriting measure on function of the specific diagnosis or the antipsychotic dose. Results indicate that participants with a schizophrenia spectrum disorder or bipolar disorder exhibit significant motor impairments and that these impairments can be readily quantified using measures of handwriting movements. Besides, they suggest that motor abnormalities are a core feature of several mental disorders and they seem to be unrelated to the pharmacological treatment.

A longitudinal approach to biological psychiatric research: The PsyCourse study

In current diagnostic systems, schizophrenia and bipolar disorder are still conceptualized as distinct categorical entities. Recently, both clinical and genomic evidence have challenged this Kraepelinian dichotomy. There are only few longitudinal studies addressing potential overlaps between these conditions. Here, we present design and first results of the PsyCourse study (N = 891 individuals at baseline), an ongoing transdiagnostic study of the affective-to-psychotic continuum that combines longitudinal deep phenotyping and dimensional assessment of psychopathology with an extensive collection of biomaterial. To provide an initial characterization of the PsyCourse study sample, we compare two broad diagnostic groups defined by the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) classification system, that is, predominantly affective (n = 367 individuals) versus predominantly psychotic disorders (n = 524 individuals). Depressive, manic, and psychotic symptoms as well as global functioning over time were contrasted using linear mixed models. Furthermore, we explored the effects of polygenic risk scores for schizophrenia on diagnostic group membership and addressed their effects on nonparticipation in follow-up visits. While phenotypic results confirmed expected differences in current psychotic symptoms and global functioning, both manic and depressive symptoms did not vary between both groups after correction for multiple testing. Polygenic risk scores for schizophrenia significantly explained part of the variability of diagnostic group. The PsyCourse study presents a unique resource to research the complex relationships of psychopathology and biology in severe mental disorders not confined to traditional diagnostic boundaries and is open for collaborations.

Premorbid adjustment trajectories in schizophrenia and bipolar disorder: A transdiagnostic cluster analysis

Despite the overlap between schizophrenia and bipolar disorder, neurodevelopmental abnormalities are thought to be associated primarily with schizophrenia. Transdiagnostic and empirical identification of subgroups based on premorbid adjustment (PMA) may enhance understanding of illness trajectories. 160 patients with bipolar I or II disorder (BD; n = 104) or schizophrenia or schizoaffective disorder (SZ; n = 56) were assessed on PMA course from childhood to late adolescence and current symptoms and functioning. A hierarchical cluster analysis was performed using social and academic PMA scores, resulting in three optimal clusters. Cluster 1 (n = 28 SZ, 65 BD) had normal social and academic PMA, the most education, and mildest current symptoms. Cluster 2 (n = 15 SZ, 24 BD) had normal social PMA but an impaired-declining academic course and had a greater proportion of males than Cluster 1. Cluster 3 (n = 13 SZ, 15 BD) had an impaired-stable social PMA and an impaired-declining academic course and the most severe current negative symptoms and childhood trauma. The proportions of SZ and BD diagnoses, current neurocognition, and functioning did not differ between clusters. These findings suggest shared neurodevelopmental abnormalities between SZ and BD, with subgroups exhibiting distinct PMA trajectories that cut across disorders.

Maternal stress, prenatal medical illnesses and obstetric complications: Risk factors for schizophrenia spectrum disorder, bipolar disorder and major depressive disorder

Maternal stress and medical illnesses during early life are well-documented environmental indicators of an increased risk of schizophrenia. Few studies, conversely, have confirmed an association with major affective disorders. The present study examined the impact of maternal stress, medical illnesses and obstetric complications on the development of severe mental disorder in 240 patients with a diagnosis of schizophrenia spectrum disorder, bipolar disorder, or major depressive disorder and matched with 85 controls. Mothers of participants were asked about stressful events during pregnancy using the Social Readjustment Scale; information on prenatal/perinatal illnesses were acquired from medical records. Schizophrenia spectrum disorder was positively associated with maternal stress (OR = 2.16), infections (OR = 7.67), inadequate weight gain (OR = 9.52) during pregnancy, and peripartum asphyxia (OR = 4.00). An increased risk of bipolar disorder was associated with head circumference < 32 cm at birth (OR = 5.40) and inversely with inadequate weight gain (OR = 0.29). Major depressive disorder diagnosis was inversely related to inadequate weight gain (OR = 0.22). These results support a role for maternal stress, medical illnesses and obstetric complications as risk factors for subsequent severe mental illness in adulthood. Further research is needed, especially with regard to affective disorders.

Brain Age in Early Stages of Bipolar Disorders or Schizophrenia

BACKGROUND

The greater presence of neurodevelopmental antecedants may differentiate schizophrenia from bipolar disorders (BD). Machine learning/pattern recognition allows us to estimate the biological age of the brain from structural magnetic resonance imaging scans (MRI). The discrepancy between brain and chronological age could contribute to early detection and differentiation of BD and schizophrenia.

METHODS

We estimated brain age in 2 studies focusing on early stages of schizophrenia or BD. In the first study, we recruited 43 participants with first episode of schizophrenia-spectrum disorders (FES) and 43 controls. In the second study, we included 96 offspring of bipolar parents (48 unaffected, 48 affected) and 60 controls. We used relevance vector regression trained on an independent sample of 504 controls to estimate the brain age of study participants from structural MRI. We calculated the brain-age gap estimate (BrainAGE) score by subtracting the chronological age from the brain age.

RESULTS

Participants with FES had higher BrainAGE scores than controls (F(1, 83) = 8.79, corrected P = .008, Cohen's d = 0.64). Their brain age was on average 2.64 ± 4.15 years greater than their chronological age (matched t(42) = 4.36, P < .001). In contrast, participants at risk or in the early stages of BD showed comparable BrainAGE scores to controls (F(2,149) = 1.04, corrected P = .70, η2 = 0.01) and comparable brain and chronological age.

CONCLUSIONS

Early stages of schizophrenia, but not early stages of BD, were associated with advanced BrainAGE scores. Participants with FES showed neurostructural alterations, which made their brains appear 2.64 years older than their chronological age. BrainAGE scores could aid in early differential diagnosis between BD and schizophrenia.

Choline Compounds of the Frontal Lobe and Temporal Glutamatergic System in Bipolar and Schizophrenia Proton Magnetic Resonance Spectroscopy Study

Purpose

Modern neuroimaging techniques allow investigating brain structures and substances involved in the pathophysiology of mental disorders, trying to find new markers of these disorders. To better understanding of the pathophysiology and differential diagnosis of schizophrenia and bipolar disorder, this study was conducted to assess the neurochemical alterations in the frontal and temporal lobes in hospitalized patients with schizophrenia and bipolar disorder.

Methods

Twenty-one subjects with schizophrenia (paranoid and differentiated types), 16 subjects with bipolar I disorder (manic, depressive, and mixed episode), and 20 healthy subjects were studied. Magnetic resonance (MR) imaging and proton resonance magnetic spectroscopy (¹H MRS) were performed on a 1.5 T scanner. Voxels of 8 cm³ were positioned in the left frontal and left temporal lobes.

Results

Glx/H₂O (GABA, glutamine, and glutamate/nonsuppressed water signal) ratios were significantly increased in the left temporal lobe in schizophrenia, but not in bipolar disorder, compared with controls. Cho/H₂O (choline/nonsuppressed water signal) ratios in the left frontal lobe had a tendency to increase in bipolar disorder and schizophrenia, relative to controls. A lower temporal lobe NAA/H₂O ratio in mixed than in manic and depressive episode of bipolar patients was also found. No other significant differences were found among three studied groups as regards NAA, Cr, and mI ratios.

Conclusions

Our results partially confirm the role of a glutamatergic system in schizophrenia, however, only in a temporal lobe. We also point to the importance of the choline-containing compounds (marker of cellular density) in the frontal lobe of patients suffering from bipolar disorder and schizophrenia. We also found the deleterious effect of mixed bipolar episode on the integrity and functioning of the temporal lobe. Glutamatergic left temporal spectroscopic changes may potentially help in differential diagnosis of schizophrenia from bipolar disorder.

Association of positive, negative, and disorganized schizotypy dimensions with affective symptoms and experiences

Schizotypy offers a useful construct for investigating the etiology, development, and expression of schizophrenia-spectrum psychopathology, as well as the comorbid expression of mood and anxiety disorders across the schizophrenia spectrum. The present study examined the associations of positive, negative, and disorganized schizotypy with affective symptoms and experiences in a sample of MTurk workers and college students (n = 575). Participants completed the Multidimensional Schizotypy Scale (MSS) and measures of depression, anxiety, social phobia, hypomanic traits, and state affect. As expected, positive schizotypy was significantly associated with hypomanic traits, whereas negative schizotypy was associated with reduced positive affect and reduced hypomanic traits. Although prior research has emphasized the association of positive schizotypy with depression and anxiety, the current results demonstrate that disorganized schizotypy is more strongly associated with elevated negative affect (over-and-above positive schizotypy). As such, these findings highlight the importance of examining disorganization of affect, in addition to the cognitive-behavioral deficits traditionally associated with disorganized schizotypy. Finally, the MSS and MSS-Brief demonstrated closely comparable findings. The present results provide further support for the construct validity of the MSS and the three-factor model of schizotypy.

Temperament in child and adolescent offspring of patients with schizophrenia and bipolar disorder

Shared vulnerability in offspring of individuals with schizophrenia (SzO) and bipolar disorder (BpO) might manifest early during development through common temperament traits. Temperament dimensions in child and adolescent BpO (N = 80), SzO (N = 34) and the offspring of community controls (CcO) (N = 101) were assessed using the Revised Dimensions of Temperament Survey. The association between temperament dimensions and lifetime psychopathology (including threshold and subthreshold DSM-IV-TR diagnoses) and current socio-academic adjustment was assessed using logistic regression. Fully adjusted models showed that both BpO and SzO scored significantly lower in the positive mood dimension and in the adaptability factor than CcO, with small-medium effect sizes (Cohen's d ~ 0.3-0.5). BpO also scored lower in the activity factor and the activity dimensions than CcO (Cohen's d ~ 0.3). Lower scores in the positive mood dimension were associated with increased risk of impaired adjustment both in BpO [OR 2.30, 95% CI (1.18-4.46)] and in SzO [OR 2.87, 95% CI (1.07-7.66)]. In BpO, lower scores in positive mood were also associated with increased likelihood of internalizing [OR 1.84, 95% CI (1.28-2.64)] and externalizing disorders [OR 1.48, 95% CI (1.01-2.18)]; in SzO, higher scores in activity and flexibility were associated with increased likelihood of internalizing [OR 2.31, 95% CI (1.22-4.38)] and externalizing disorders [OR 3.28, 95% CI (1.2-9)], respectively. Early difficulties in emotion regulation might represent a shared vulnerability phenotype in BpO and SzO. The identification of extreme temperament traits could help to characterize subgroups at greater risk of psychopathology and impaired adjustment, in which targeted interventions are warranted.

Health Care Resource Use, Costs, and Diagnosis Patterns in Patients With Schizophrenia and Bipolar Disorder: Real-world Evidence From US Claims Databases

PURPOSE

Schizophrenia (SCZ) and bipolar disorder (BD) are typically viewed as nonconcurrent psychiatric disorders, yet patients may experience mood and SCZ symptoms simultaneously. Several studies have shown overlap between SCZ and BD symptoms and susceptibility genes. This study explored the following: (1) patterns of administrative claims; (2) demographic characteristics and comorbidities; (3) health care resource use; and (4) health care costs in patients with diagnoses of SCZ, type I BD (BD-I), and both in a real-world setting.

METHODS

This study was a retrospective cohort trial using 4.5years (January 1, 2012-June 30, 2016) of Truven MarketScan commercial, Medicaid, and Medicare supplemental databases. We considered a patient to have a new episode of SCZ if he or she had 1 inpatient claim or 2 outpatient claims for SCZ within the identification period (January 1, 2013-June 30, 2015). BD-I was defined in an analogous way. Three study cohorts were defined: (1) SCZ alone (cohort I), met the claims-based diagnostic criteria for SCZ; (2) BD-I alone (cohort II), met the claims-based diagnostic criteria for BD-I; and (3) BD-I and SCZ (cohort III), met the claims-based diagnostic criteria for both SCZ and BD-I.

FINDINGS

Of the 63,725 patients in the final sample, 11.5% (n = 7336) had a new episode of SCZ alone (cohort I), 80.8% (n = 51,480) had a new episode of BD-I alone (cohort II), and 7.7% (n = 4909) had new episodes of both SCZ and BD-I (cohort III). Considering cohort III, 18.8% (n = 927) received both diagnoses on the same day. In the year after diagnosis, the cohort having a diagnosis of both SCZ and BD-I (cohort III) had the highest all-cause hospitalization rates (67.4% vs 39.5% in SCZ alone and 33.7% in BD-I alone) and the highest mean (SD) number of emergency department visits (3.44 [7.1] vs 1.39 [3.5] in SCZ alone and 1.29 [3.2] in BD-I alone). All-cause total health care costs were highest in the cohort having a diagnosis of both SCZ and BD-I (mean [SD]), $51,085 [$62,759]), followed by the SCZ alone cohort ($34,204 [$52,995]), and the BD-I alone cohort ($26,396 [$48,294]).

IMPLICATIONS

Our analyses indicate that a substantial number of patients received diagnoses of both SCZ and BD-I, based on claims, in a 2.5-year period. Patients with a diagnosis of both SCZ and BD-I had higher health care utilization and costs than patients with either diagnosis alone. We identified differential patient characteristics, utilization of medications and health care services, and health care costs among the cohorts.

Genome-wide association study results for educational attainment aid in identifying genetic heterogeneity of schizophrenia

Higher educational attainment (EA) is negatively associated with schizophrenia (SZ). However, recent studies found a positive genetic correlation between EA and SZ. We investigate possible causes of this counterintuitive finding using genome-wide association study results for EA and SZ (N = 443,581) and a replication cohort (1169 controls; 1067 cases) with deeply phenotyped SZ patients. We find strong genetic dependence between EA and SZ that cannot be explained by chance, linkage disequilibrium, or assortative mating. Instead, several genes seem to have pleiotropic effects on EA and SZ, but without a clear pattern of sign concordance. Using EA as a proxy phenotype, we isolate FOXO6 and SLITRK1 as novel candidate genes for SZ. Our results reveal that current SZ diagnoses aggregate over at least two disease subtypes: one part resembles high intelligence and bipolar disorder (BIP), while the other part is a cognitive disorder that is independent of BIP.

Social cognition moderates the relationship between neurocognition and community functioning in bipolar disorder

BACKGROUND

Schizophrenia (SZ) studies suggest that neurocognition predicts functional outcome and that social cognition mediates this relationship. Bipolar disorder (BD) patients also have cognitive, social, and functional impairments but the relationship among these factors in BD is not well established. We assessed whether social cognition modulates the influence of neurocognition on community functioning in BD, as found in SZ.

METHODS

200 BD patients and 49 healthy controls (HC) were administered and compared on a battery of tests assessing neurocognition, social cognition, and community functioning. We conducted a series of regression analyses to investigate potential mediation or moderation of social cognition on the relationship between neurocognition and community functioning.

RESULTS

BD patients performed worse on neurocognitive domains of processing speed, attention, verbal learning, and global neurocognition. Also, BD patients performed worse on theory of mind, the social cognition composite score, and community functioning. Neurocognition did not significantly predict functional outcome in our BD sample. However, we found a moderating effect of social cognition: among patients with poor social cognition, better neurocognition was associated with better community functioning, a relationship not seen in BD patients with good social cognition.

LIMITATIONS

The study was limited by a relatively small HC group and assessing one subtype of functioning status.

CONCLUSIONS

The relationship between neurocognition and community functioning in BD may be dependent on social cognition status, implying the presence of social cognitive heterogeneity. Results may be relevant to choosing proper treatment interventions depending on the patient's social cognitive level.

Could schizoaffective disorder, schizophrenia and bipolar I disorder be distinguishable using cognitive profiles?

This study seeks to determine whether the cognition profiles of patients with schizoaffective disorder (SAD), schizophrenia and bipolar I disorder (BD) are distinguishable. A total of 227 participants, comprising 88 healthy control subjects, 50 patients with SAD, 48 patients with schizophrenia and 41 patients with BD, were recruited. The participants' cognitive functions were evaluated using the Brief Assessment of Cognition in Schizophrenia (BACS). A discriminant functions analysis (DFA) was conducted to determine whether using cognitive performance can be used to distinguish these participant groups. Relative to healthy control subjects, patients with SAD, schizophrenia and BD exhibited significant deficits in all cognitive domains (verbal memory, working memory, motor speed, verbal fluency, attention and processing speed, executive function and a composite BACS score). Among the three patient groups, the schizophrenia group exhibited particularly impaired motor speed, and the BD group performed best in attention, processing speed, executive function and the composite BACS score. The classification accuracy rates of patients with SAD, schizophrenia and BD in the DFA model were 38%, 47.9% and 46.3%, respectively. These findings suggest that the impairments of some cognitive domains were less severe in patients with BD than in patients with schizophrenia or SAD.

Juvenile treatment with mGluR2/3 agonist prevents schizophrenia-like phenotypes in adult by acting through GSK3β

Prodromal memory deficits represent an important marker for the development of schizophrenia (SZ), in which glutamatergic hypofunction occurs in the prefrontal cortex (PFC). The mGluR2/3 agonist LY379268 (LY37) attenuates excitatory N-methyl-D-aspartate receptor (NMDAR)-induced neurotoxicity, a central pathological characteristic of glutamatergic hypofunction. We therefore hypothesized that early treatment with LY37 would rescue cognitive deficits and confer benefits for SZ-like behaviors in adults. To test this, we assessed whether early intervention with LY37 would improve learning outcomes in the Morris Water Maze for rats prenatally exposed to methylazoxymethanol acetate (MAM), a neurodevelopmental SZ model. We found that a medium dose of LY37 prevents learning deficits in MAM rats. These effects were mediated through postsynaptic mGluR2/3 via improving GluN2B-NMDAR function by inhibiting glycogen synthase kinase-3β (GSK3β). Furthermore, dendritic spine loss and learning and memory deficits observed in adult MAM rats were restored by juvenile LY37 treatment, which did not change prefrontal neuronal excitability and glutamatergic synaptic transmission in adult normal rats. Our results provide a mechanism for mGluR2/3 agonists against NMDAR hypofunction, which may prove to be beneficial in the prophylactic treatment of SZ.

Course of Cognitive Development From Infancy to Early Adulthood in the Psychosis Spectrum

Importance

Most patients with psychotic disorders experience severe cognitive impairment, but the onset and course of this impairment remain unclear. Moreover, the course of cognitive functions in other psychiatric conditions remains largely unexamined.

Objective

To chart the course of general and specific cognitive functions in individuals with psychotic disorders, psychotic experiences, and depression.

Design, Setting, and Participants

The Avon Longitudinal Study of Parents and Children (ALSPAC) is a prospective cohort study comprising all live births between April 1, 1991, and December 31, 1992, in Avon, England. The dates of analysis were September 2015 to July 2016. Participants who underwent cognitive testing at ages 18 months and 4, 8, 15, and 20 years and psychiatric assessment at age 18 years were included.

Main Outcomes and Measures

Individuals with psychotic disorder, psychosis with depression, psychotic experiences, and depression were compared with controls. Outcomes were full-scale, verbal, and nonverbal IQ at ages 18 months and 4, 8, 15, and 20 years, as well as measures of processing speed, working memory, language, visuospatial ability, and attention at ages 8 and 20 years.

Results

The following numbers of individuals were available for analyses in this longitudinal birth cohort study: 511 (238 male [46.6%]) at age 18 months (mean [SD] age, 1.53 [0.03] years), 483 (229 male [47.4%]) at age 4 years (mean [SD] age, 4.07 [0.03] years), 3930 (1679 male [42.7%]) at age 8 years (mean [SD] age, 8.65 [0.29] years), 3783 (1686 male [44.6%]) at age 15 years (mean [SD] age, 15.45 [0.27] years), and 257 (90 male [35.0%]) at age 20 years (mean [SD] age, 20.06 [0.55] years). Individuals with psychotic disorder showed continually increasing deficits between infancy (18 months) and adulthood (20 years) in full-scale IQ (effect size of change [ESΔ] = -1.09, P = .02) and nonverbal IQ (ESΔ = -0.94, P = .008). The depression group showed a small, increasing deficit in nonverbal IQ (ESΔ = -0.29, P = .04) between infancy and adulthood. Between ages 8 and 20 years, the psychotic disorder group exhibited developmental lags (ie, slower growth) in measures of processing speed (ESΔ = -0.68, P = .001), working memory (ESΔ = -0.59, P = .004), and attention (ESΔ = -0.44, P = .001) and large, static deficits in measures of language (ES = -0.87, P = .005) and visuospatial ability (ES = -0.90, P = .001). There was only weak evidence for cognitive deficits in the psychosis with depression group and the psychotic experiences group.

Conclusions and Relevance

The findings herein suggest that the origins of psychotic disorder involve dynamic developmental processes, affecting both verbal and nonverbal abilities throughout the first 2 decades of life and leading to increasing dysfunction. These developmental processes do not manifest in other psychiatric disorders, such as psychosis with depression and depression.

Levels of Cognitive Control: A Functional Magnetic Resonance Imaging-Based Test of an RDoC Domain Across Bipolar Disorder and Schizophrenia

In recent years, the boundaries of psychopathology as defined by diagnostic categories have been criticized as inadequately 'carving nature at its joints' with respect to the neurobiology of major mental disorders. In 2010 the NIMH launched the Research Domain Criteria (RDoC) framework for understanding mental illnesses as brain circuit disorders that extend beyond DSM-defined diagnoses. In the present study we focus on cognitive dysfunction, a core feature of schizophrenia (SZ) and bipolar disorder (BPD), and use functional magnetic resonance imaging (fMRI) during a cognitive control (CC) task in recent onset patients to test the hypothesis that at a behavioral and underlying neural circuitry level these deficits exist on a continuum (as opposed to showing categorical differences) across the two disorders. In total, 53 healthy controls, 24 recent (<1 y) onset patients with BPD Type I with psychotic features, and 70 recent onset patients with SZ performed the AX-Continuous Performance Task while undergoing event-related fMRI at 1.5 T. In addition to behavior task-associated response was examined in frontoparietal regions-of-interest. In an a priori contrast-based analysis, significant deficits across patient groups (vs controls) were observed on CC-associated performance as well as frontoparietal response. These analyses further revealed a continuum of deficits in which BPD showed intermediate levels of CC relative to controls and SZ. Poor CC was associated with poverty and disorganization symptoms across patient groups. These results support the hypothesis that CC dysfunction in BPD and SZ reflects a continuum of deficits that cuts across traditional, DSM-based classification. Implications for the neurobiology of these diseases are discussed.

Cognitive development prior to onset of psychosis

Schizophrenia patients commonly exhibit substantial and diffuse cognitive impairment. Evidence suggests that subtle cognitive deficits are already apparent in childhood and adolescence, many years prior to onset of psychosis. While there is almost unequivocal evidence of some degree of cognitive impairment in individuals who later develop schizophrenia, the literature remains inconclusive regarding the exact nature of this impairment and warrants careful review and interpretation. Meta-analytic findings suggest that individuals who later develop schizophrenia, but not related disorders, such as bipolar disorder, exhibit a premorbid IQ deficit of around 8 points. Several studies have also found evidence for premorbid deficits across most cognitive domains, such as language, processing speed and executive functions. Longitudinal studies, although rare, suggest that individuals who go on to develop schizophrenia may show a course of increasing cognitive impairment prior to onset of psychosis. While evidence regarding the etiology of premorbid deficits is scarce, common and rare genetic variants, as well as environmental factors such as obstetric complications and cannabis use may play an important role and warrant further examination. In this selected review, we give an overview of population-based studies on premorbid cognitive deficits in schizophrenia, with a special focus on evidence regarding the specificity, profile and course of these deficits.

Association of Genetic Risk for Schizophrenia and Bipolar Disorder With Infant Neuromotor Development

This study uses data from the population-based Generation R Study of Rotterdam, the Netherlands, to assess an association of genetic risk for schizophrenia and bipolar disorder with infant neuromotor development.

The slow death of the concept of schizophrenia and the painful birth of the psychosis spectrum

The concept of schizophrenia only covers the 30% poor outcome fraction of a much broader multidimensional psychotic syndrome, yet paradoxically has become the dominant prism through which everything 'psychotic' is observed, even affective states with mild psychosis labelled 'ultra-high risk' (for schizophrenia). The inability of psychiatry to frame psychosis as multidimensional syndromal variation of largely unpredictable course and outcome - within and between individuals - hampers research and recovery-oriented practice. 'Psychosis' remains firmly associated with 'schizophrenia', as evidenced by a vigorous stream of high-impact but non-replicable attempts to 'reverse-engineer' the hypothesized biological disease entity, using case-control paradigms that cannot distinguish between risk for illness onset and risk for poor outcome. In this paper, the main issues surrounding the concept of schizophrenia are described. We tentatively conclude that with the advent of broad spectrum phenotypes covering autism and addiction in DSM5, the prospect for introducing a psychosis spectrum disorder - and modernizing psychiatry - appears to be within reach.

Meta-analysis of longitudinal studies of cognition in bipolar disorder: comparison with healthy controls and schizophrenia

BACKGROUND

Bipolar disorder (BP) is associated with significant cognitive impairment. Recent evidence suggests that cognitive deficits are already evident after first-episode mania. However, it is not clear whether BP is associated with further decline in cognitive functions in individuals with established illness. Aim of this meta-analytic review was to examine longitudinal neurocognitive changes in BP and to compare trajectory of cognitive deficits in BP with schizophrenia and healthy controls.

METHODS

Electronic databases were searched for the studies published between January 1987 and November 2016. In total 22 reports were included in the current meta-analysis. The main analysis assessed the longitudinal change in cognition in 643 patients with BP. Further analyses were conducted in studies investigating cognitive changes in BP along with healthy controls (459 BP and 367 healthy controls) and schizophrenia (172 BP and 168 schizophrenia).

RESULTS

There was no cognitive decline overtime neither in short-term (mean duration = 1.5 years) nor in long-term (mean duration = 5.5 years) follow-up studies in BP. In contrast, there was evidence for modest improvements in task performance in memory and working memory at follow-up. The trajectory of cognitive functioning in BP was not significantly different from changes in schizophrenia and healthy controls.

CONCLUSIONS

Together with the findings in early BP and individuals at genetic risk for BP, current findings suggest that neurodevelopmental factors might play a significant role in cognitive deficits in BP and do not support the notion of progressive cognitive decline in most patients with BP.

The clinical trajectory of emerging bipolar disorder among the high-risk offspring of bipolar parents: current understanding and future considerations

BACKGROUND

Relatively little is known about the onset of bipolar disorder, yet the early illness course is already associated with significant morbidity and mortality. Therefore, characterizing the bipolar illness trajectory is key to risk prediction and early intervention advancement.

MAIN BODY

In this narrative review, we discuss key findings from prospective longitudinal studies of the high-risk offspring of bipolar parents and related meta-analyses that inform us about the clinical trajectory of emerging bipolar disorder. Challenges such as phenotypic and etiologic heterogeneity and the non-specificity of early symptoms and syndromes are highlighted. Implications of the findings for both research and clinical practice are discussed.

CONCLUSION

Bipolar disorder in young people at familial risk does not typically onset with a hypomanic or manic episode. Rather the first activated episode is often preceded by years of impairing psychopathological states that vary over development and across emerging bipolar subtype. Taking heterogeneity into account and adopting a more comprehensive approach to diagnosis seems necessary to advance earlier identification and our understanding of the onset of bipolar disorder.

Profile and Determinants of Disability in Psychotic Disorders in Nigeria

We compared profile and predictors of disability among 210 patients with schizophrenia, schizoaffective disorder, bipolar I disorder with psychosis and depression with psychosis, respectively in a Nigerian clinical population, using the WHO Disability Assessment Schedule, (2.0). Severity of psychosis was determined with Positive and Negative Symptoms Scale, functioning was assessed using the Global Assessment of Functioning Scale, medication adherence with the Medication Adherence Questionnaire. Analyses were by SPSS 20.0. There were remarkable differences in the predictors of disability across these psychotic disorders. The findings strengthens the significance of psychosocial rehabilitation in patients with psychosis as clinical remission and medication adherence did not equate functional recovery.

Intellectual Functioning in Offspring of Parents with Bipolar Disorder: A Review of the Literature

Impaired intellectual functioning is an important risk factor for the emergence of severe mental illness. Unlike many other forms of mental disorder however, the association between bipolar disorder and intellectual deficits is unclear. In this narrative review, we examine the current evidence on intellectual functioning in children and adolescents at risk for developing bipolar disorder. The results are based on 18 independent, peer-reviewed publications from 1980 to 2017 that met criteria for this study. The findings yielded no consistent evidence of lower or higher intellectual quotient (IQ) in offspring of parents diagnosed with bipolar disorder. Some tentative evidence was found for lower performance IQ in offspring of bipolar parents as compared to controls. It is recommended that future research examine variability in intellectual functioning and potential moderators. These findings demonstrate the need to examine how intellectual functioning unfolds across development given the potential role of IQ as a marker of vulnerability or resilience in youth at high risk for affective disorders.

Developmental Differences Between Schizophrenia and Bipolar Disorder

Ample evidence supports a neurodevelopmental origin in some cases of schizophrenia (SZ). More inconsistent information is available for bipolar disorder (BD). We herein review studies with a focus on premorbid (adjustment and functionality) and early developmental milestones that include both SZ and BD patients. A search was performed in the PubMed electronic database, retrieving 619 abstracts; 30 were ultimately included in this systematic review. Eight prospective cohorts, 15 retrospective studies, and 7 studies based on national registries. Psychomotor developmental deviations and general adjustment problems characterize the childhood of subjects later diagnosed with SZ or BD; they are more marked in those later diagnosed with SZ vs BD, earlier onset vs later onset, and psychotic vs nonpsychotic disorders. Cognitive impairment follows a linear risk trend for SZ and a U-shaped trend for BD. Social isolation and visuoperceptual/reading anomalies more frequently antecede SZ. Pervasive developmental disorders increase the risk for both SZ and BD, more so in cases with normal intelligence. The predictive risk of each isolated developmental marker is low, but a significant percentage of subjects with SZ and a minority of adults with BD showed signs of premorbid abnormalities in childhood. The great limitation is still the lack of studies comparing SZ and BD that include psychotic and nonpsychotic bipolar cases separately. There are many cases, even in childhood/adolescent SZ, where no premorbid anomalies are found, and immunological disorders or other etiologies should be searched for. At least in cases with clear neurodevelopmental markers, rare genetic variants should be investigated.

Trends in standardized mortality among individuals with schizophrenia, 1993-2012: a population-based, repeated cross-sectional study

BACKGROUND

We examined mortality time trends and premature mortality among individuals with and without schizophrenia over a 20-year period.

METHODS

In this population-based, repeated cross-sectional study, we identified all individual deaths that occurred in Ontario between 1993 and 2012 in persons aged 15 and over. We plotted overall and cause-specific age- and sex-standardized mortality rates (ASMRs), stratified all-cause ASMR trends by sociodemographic characteristics, and analyzed premature mortality using years of potential life lost. Additionally, we calculated mortality rate ratios (MRRs) using negative binomial regression with adjustment for age, sex, income, rurality and year of death.

RESULTS

We identified 31 349 deaths among persons with schizophrenia, and 1 589 902 deaths among those without schizophrenia. Mortality rates among people with schizophrenia were 3 times higher than among those without schizophrenia (adjusted MRR 3.12, 95% confidence interval 3.06-3.17). All-cause ASMRs in both groups declined in parallel over the study period, by about 35%, and were higher for men, for those with low income and for rural dwellers. The absolute ASMR difference also declined throughout the study period (from 16.15 to 10.49 deaths per 1000 persons). Cause-specific ASMRs were greater among those with schizophrenia, with circulatory conditions accounting for most deaths between 1993 and 2012, whereas neoplasms became the leading cause of death for those without schizophrenia after 2005. Individuals with schizophrenia also died, on average, 8 years younger than those without schizophrenia, losing more potential years of life.

INTERPRETATION

Although mortality rates among people with schizophrenia have declined over the past 2 decades, specialized approaches may be required to close the persistent 3-fold relative mortality gap with the general population.

Medical Co-morbidities Among Patients with Severe Mental Illnesses in a Community Health Facility in Nigeria

To examine prevalence of medical comorbidity (MCM) in schizophrenia (n = 1310) and in bipolar disorder (n = 1307) and the association of high burden of MCM (≥3 MCM) with duration of untreated illness, number of episodes, functioning, poly-medication and lifetime hospitalization for the mental disorder. Participants were recruited from a private psychiatric facility in Ibadan, Nigeria between 2004 and 2013 and enquiry made about the lifetime occurrence of 20 common chronic diseases including common tropical diseases. Psychiatric diagnosis was made using the Structured Clinical Interview for DSM IV Axis I disorder (SCID). Except for nutritional anemia, dermatitis and intestinal Helminthiasis, patients with schizophrenia were not at higher odds of reporting MCM than those with bipolar disorder. DUI ≥2 years, episodes of illness ≥3, being on multiple neuroleptics and history of previous hospitalization were significantly associated with high burden of MCM in schizophrenia and episodes of illness ≥3, reduced functioning and history of previous hospitalization with bipolar disorder. Schizophrenia and bipolar disorder are associated with high rates of medical comorbidity. Treatment of this medical comorbidity is essential in order to improve the outcomes for patients with bipolar disorder and schizophrenia.

Shared abnormality of white matter integrity in schizophrenia and bipolar disorder: A comparative voxel-based meta-analysis

Patients with schizophrenia and bipolar disorder (BD) shared a significant overlap in genetic susceptibility, pharmacological treatment responses, neuropsychological deficits, and epidemiological features. However, it remains unknown whether these clinical overlaps are mediated by shared or disorder-specific abnormalities of white matter integrity. In this voxel-based meta-analytic comparison of whole-brain white matter integrity, we aimed to identify the shared or disorder-specific structural abnormalities between schizophrenia and BD. A comprehensive literature search was conducted up to February 2016 to identify studies that compared between patients and healthy controls (HC) by using whole-brain diffusion approach (schizophrenia: 24 datasets with 754 patients vs. 775 HC; BD: 23 datasets with 705 patients vs. 679 HC). Voxel-wise meta-analyses were conducted and restricted to unified template using seed-based d-Mapping. Abnormal white matter integrity was calculated within each condition and a direct comparison of effect size was performed of alterations between two conditions. Two regions with significant reductions of fractional anisotropy (FA) characterized abnormal water diffusion in both disorders: the genu of the corpus callosum (CC) and posterior cingulum fibers. There was no significant difference found between the two disorders. Our results highlighted shared impairments of FA at genu of the CC and left posterior cingulum fibers, which suggests that, phenotypic overlap between schizophrenia and BD could be related to common brain circuit dysfunction.

Trajectories of Neighborhood Cohesion in Childhood, and Psychotic and Depressive Symptoms at Age 13 and 18 Years

OBJECTIVE

Exposure to adverse social environments has been associated with psychotic and depressive symptoms in adolescence in cross-sectional studies, but the longitudinal relation is unclear. This study examined whether longitudinal trajectories of exposure to adverse social environments across childhood are associated with psychotic experiences and depressive symptoms in adolescence.

METHOD

Data on participants from the Avon Longitudinal Study of Parents and Children (ALSPAC) were used to estimate longitudinal trajectories of childhood exposure to neighborhood cohesion (NC), discord (ND), and stress (NS) using latent class growth modeling. Logistic regression was used to examine the association between these trajectories and psychotic experiences and depressive symptoms at 13 and 18 years of age, adjusting for maternal psychopathology, participant sociodemographic and socioeconomic characteristics, and area-level deprivation.

RESULTS

A dose-response association was observed between higher NS and the odds of psychotic experiences at 13 years (medium NS, adjusted odds ratio [aOR] 1.25, 95% CI 1.05-1.49; high NS, aOR 1.77, 95% CI 1.30-2.40), whereas high levels of ND predicted psychotic experiences at 18 years (aOR 1.50, 95% CI 1.10-2.07). High levels of NC (aOR 1.43, 95% CI 1.02-1.71) and NS (aOR 1.55, 95% CI 1.07-2.26) were associated with increased odds of high depressive symptoms at 18 years in a dose-response fashion.

CONCLUSION

Prolonged and more severe exposure to adverse social environments is associated with greater odds of developing psychotic and depressive symptoms in late adolescence.

The interplay of childhood behavior problems and IQ in the development of later schizophrenia and affective psychoses

Schizophrenia and affective psychoses are both associated with impaired social functioning, but the extent to which childhood behavioral impairments are present prior to onset of illness is less well studied. Moreover, the concurrent relationship of childhood behavior problems and premorbid IQ with subsequent psychotic disorder has not been established. We investigated whether childhood behavior problems are associated with increased risk for adult schizophrenia or affective psychosis, independently and in combination with IQ. The study included individuals with schizophrenia (N=47), affective psychoses (N=45) and non-psychotic controls (N=1496) from the New England Family Study. Behavior problems were prospectively assessed from standardized clinician observations at ages 4 and 7. IQ was assessed with the Stanford-Binet at age 4 and the Wechsler Intelligence Scale for Children at age 7. We found externalizing problems at age 4 and externalizing and internalizing problems at age 7 were associated with later schizophrenia, and both internalizing and externalizing problems at ages 4 and 7 were associated with later development of affective psychoses. Lower IQ at ages 4 and 7 was associated with schizophrenia, while lower IQ was associated with affective psychoses at age 7 only. Examined simultaneously, both lower IQ and behavior problems remained associated with risk of schizophrenia, while only behavior problems remained associated with affective psychoses. Behavior problems appear to be a general marker of risk of adult psychotic disorder, while lower childhood IQ is more specific to risk of schizophrenia. Future research should clarify the premorbid evolution of behavior and cognitive problems into adult psychosis.

Contextual Cognitive-Behavioral Therapies Across the Psychosis Continuum

Abstract. Considering several etiologic, therapeutic, and comorbidity-related factors, a psychosis continuum model has been proposed for the understanding and treatment of psychotic disorders. Within the new emerging treatment approaches, Contextual Cognitive-Behavioral Therapies (CCBT) seem to hold promise for the psychosis continuum. However, considering their novelty for this specific population, the quality of efficacy evidence remains unclear. Objective: To examine, critically analyze, and summarize the results from studies based on therapeutic models within the CCBT approach (Mindfulness and Acceptance-based interventions, Compassion-Focused Therapy, Dialectical Behavior Therapy, and Metacognitive Therapy) for patients with a diagnosis within the psychosis continuum (schizophrenia, schizoaffective disorder, bipolar disorder). Methods: Three leading electronic databases (MEDLINE/PUBMED; PsycINFO; Cochrane Library), a grey literature database (OpenGrey), and registered clinical trials (ClinicalTrials.Gov) were searched using combinations of key terms regarding the CCBT models and the diagnosis considered. Reference lists of the relevant studies and reviews were searched. Only Randomized Controlled Trials (RCTs) were included. The “Cochrane Risk of Bias Assessment Tool” was used for quality assessment. Results: A total of 17 articles were included. This review was based on a majority of unclear or low risk of bias studies. Benefits regarding clinical variables such as psychotic symptoms, anxiety and depression, functioning or quality of life were found. Conclusion: Overall the studies supported some benefits of CCBT approaches for the psychosis continuum. The conceptual perspective on treatment has changed, nevertheless the outcomes assessed are still symptom-focused and there is still need for improvement. Methodological considerations and future directions are presented.

Connectome Disconnectivity and Cortical Gene Expression in Patients With Schizophrenia

BACKGROUND

Genome-wide association studies have identified several common risk loci for schizophrenia (SCZ). In parallel, neuroimaging studies have shown consistent findings of widespread white matter disconnectivity in patients with SCZ.

METHODS

We examined the role of genes in brain connectivity in patients with SCZ by combining transcriptional profiles of 43 SCZ risk genes identified by the recent genome-wide association study of the Schizophrenia Working Group of the Psychiatric Genomics Consortium with data on macroscale connectivity reductions in patients with SCZ. Expression profiles of 43 Psychiatric Genomics Consortium SCZ risk genes were extracted from the Allen Human Brain Atlas, and their average profile across the cortex was correlated to the pattern of cortical disconnectivity as derived from diffusion-weighted magnetic resonance imaging data of patients with SCZ (n = 48) and matched healthy controls (n = 43).

RESULTS

The expression profile of SCZ risk genes across cortical regions was significantly correlated with the regional macroscale disconnectivity (r = .588; p = .017). In addition, effects were found to be potentially specific to SCZ, with transcriptional profiles not related to cortical disconnectivity in patients with bipolar I disorder (diffusion-weighted magnetic resonance imaging data; 216 patients, 144 controls). Further examination of correlations across all 20,737 genes present in the Allen Human Brain Atlas showed the set of top 100 strongest correlating genes to display significant enrichment for the disorder, potentially identifying new genes involved in the pathophysiology of SCZ.

CONCLUSIONS

Our results suggest that under disease conditions, cortical areas with pronounced expression of risk genes implicated in SCZ form central areas for white matter disconnectivity.

Do the Trajectories of Bipolar Disorder and Schizophrenia Follow a Universal Staging Model?

OBJECTIVE

The purpose of this study is to address the question of whether a universal staging model of severe psychiatric disorders is a viable direction for future research by examining the extant literature.

METHOD

A narrative review was conducted of the relevant historical, conceptual, and empirical literature pertaining to the clinical trajectory of bipolar disorder and schizophrenia and issues relevant to staging.

RESULTS

There is substantive evidence that classic recurrent bipolar disorder is separable from schizophrenia on the basis of family history, developmental and clinical course, treatment response, and neurobiological findings. However, because of the intrinsic heterogeneity of diagnostic categories that has been amplified by recent changes in psychiatric taxonomy, key distinctions between the groups have become obfuscated. While mapping risk and illness markers to emerging psychopathology is a logical approach and may be of value for some psychiatric disorders and/or their clinical subtypes, robust evidence supporting identifiable stages per se is still lacking. Presently, even rudimentary stages such as prodromes cannot be meaningfully applied across different disorders and no commonalities can be found for the basis of universal staging.

CONCLUSIONS

Advances in the prediction of risk, accurate early illness detection, and tailored intervention will require mapping biomarkers and other risk indicators to reliable clinical phases of illness progression. Given the capricious nature of mood and psychotic disorders, this task is likely to yield success only if conducted in narrowly defined subgroups of individuals at high risk for specific illnesses. This approach is diametrically opposite to that being promulgated by proponents of a universal staging model.

Genetic association of rs1344706 in ZNF804A with bipolar disorder and schizophrenia susceptibility in Chinese populations

Rs1344706 in the the zinc finger protein 804A (ZNF804A) gene has been identified to be associated with schizophrenia and bipolar disorder (BD) in Europeans. However, whether rs1344706 is associated with schizophrenia in Chinese populations remains inconclusive; furthermore, the association between rs1344706 and BD in Chinese populations has been rarely explored. To explore the association between rs1344706 and schizophrenia/BD in Chinese populations, we genotyped rs1344706 among 1128 Chinese subjects (537 patients with BD and 591 controls) and found that rs1344706 showed marginal allelic association with BD (P = 0.028) with T-allele being more prevalent in cases than that in controls (OR = 1.19, 95% CI 1.03–1.37). Meta-analysis of rs1344706 by pooling all available data showed that rs1344706 was significantly associated with BD (P = 0.001). Besides, positive association of rs1344706 with schizophrenia was observed in Northern Chinese (P = 0.005). Furthermore, ZNF804A is highly expressed in human and mouse brains, especially in prenatal stage.

Realising stratified psychiatry using multidimensional signatures and trajectories

Background

Stratified or personalised medicine targets treatments for groups of individuals with a disorder based on individual heterogeneity and shared factors that influence the likelihood of response. Psychiatry has traditionally defined diagnoses by constellations of co-occurring signs and symptoms that are assigned a categorical label (e.g. schizophrenia). Trial methodology in psychiatry has evaluated interventions targeted at these categorical entities, with diagnoses being equated to disorders. Recent insights into both the nosology and neurobiology of psychiatric disorder reveal that traditional categorical diagnoses cannot be equated with disorders. We argue that current quantitative methodology (1) inherits these categorical assumptions, (2) allows only for the discovery of average treatment response, (3) relies on composite outcome measures and (4) sacrifices valuable predictive information for stratified and personalised treatment in psychiatry.

Methods and findings

To achieve a truly ‘stratified psychiatry’ we propose and then operationalise two necessary steps: first, a formal multi-dimensional representation of disorder definition and clinical state, and second, the similar redefinition of outcomes as multidimensional constructs that can expose within- and between-patient differences in response. We use the categorical diagnosis of schizophrenia—conceptualised as a label for heterogeneous disorders—as a means of introducing operational definitions of stratified psychiatry using principles from multivariate analysis. We demonstrate this framework by application to the Clinical Antipsychotic Trials of Intervention Effectiveness dataset, showing heterogeneity in both patient clinical states and their trajectories after treatment that are lost in the traditional categorical approach with composite outcomes. We then systematically review a decade of registered clinical trials for cognitive deficits in schizophrenia highlighting existing assumptions of categorical diagnoses and aggregate outcomes while identifying a small number of trials that could be reanalysed using our proposal.

Conclusion

We describe quantitative methods for the development of a multi-dimensional model of clinical state, disorders and trajectories which practically realises stratified psychiatry. We highlight the potential for recovering existing trial data, the implications for stratified psychiatry in trial design and clinical treatment and finally, describe different kinds of probabilistic reasoning tools necessary to implement stratification.

Autistic and schizotypal traits and global functioning in bipolar I disorder

OBJECTIVE

To determine the expression of autistic and positive schizotypal traits in a large sample of adults with bipolar I disorder (BD I), and the effect of co-occurring autistic and positive schizotypal traits on global functioning in BD I.

METHOD

Autistic and positive schizotypal traits were self-assessed in 797 individuals with BD-I recruited by the Bipolar Disorder Research Network. Differences in global functioning (rated using the Global Assessment Scale) during lifetime worst depressive and manic episodes (GASD and GASM respectively) were calculated in groups with high/low autistic and positive schizotypal traits. Regression analyses assessed the interactive effect of autistic and positive schizotypal traits on global functioning.

RESULTS

47.2% (CI=43.7-50.7%) showed clinically significant levels of autistic traits, and 23.22% (95% CI=20.29-26.14) showed clinically significant levels of positive schizotypal traits. In the worst episode of mania, the high autistic, high positive schizotypal group had better global functioning compared to the other groups. Individual differences analyses showed that high levels of both traits were associated with better global functioning in both mood states.

LIMITATIONS

Autistic and schizotypal traits were assessed using self-rated questionnaires.

CONCLUSIONS

Expression of autistic and schizotypal traits in adults with BD I is prevalent, and may be important to predict illness aetiology, prognosis, and diagnostic practices in this population. Future work should focus on replicating these findings in independent samples, and on the biological and/or psychosocial mechanisms underlying better global functioning in those who have high levels of both autistic and positive schizotypal traits.

The dysregulated brain: consequences of spatial and temporal brain complexity for bipolar disorder pathophysiology and diagnosis

Increasingly, evidence has been accumulating emphasizing the importance of looking at bipolar disorder (BD) from a neurodevelopmental and transdimensional perspective to better understand its origins and its course. In this overview article, the problems facing pathophysiological psychiatric research in BD are addressed and interpreted in the light of brain complexity. Brain complexity can be split into spatial complexity, which constitutes the physiological levels of the central nervous system (i.e., the genetic, molecular, cellular, neuronal circuit and phenomenological levels), and temporal complexity, that is, neurodevelopment. The consequences of this consideration are discussed and suggestions for clinical practice and pathophysiological psychiatric research are made.

Auditory Vigilance and Working Memory in Youth at Familial Risk for Schizophrenia or Affective Psychosis in the Harvard Adolescent Family High Risk Study

BACKGROUND

The degree of overlap between schizophrenia (SCZ) and affective psychosis (AFF) has been a recurring question since Kraepelin's subdivision of the major psychoses. Studying nonpsychotic relatives allows a comparison of disorder-associated phenotypes, without potential confounds that can obscure distinctive features of the disorder. Because attention and working memory have been proposed as potential endophenotypes for SCZ and AFF, we compared these cognitive features in individuals at familial high-risk (FHR) for the disorders.

METHODS

Young, unmedicated, first-degree relatives (ages, 13-25 years) at FHR-SCZ (n=41) and FHR-AFF (n=24) and community controls (CCs, n=54) were tested using attention and working memory versions of the Auditory Continuous Performance Test. To determine if schizotypal traits or current psychopathology accounted for cognitive deficits, we evaluated psychosis proneness using three Chapman Scales, Revised Physical Anhedonia, Perceptual Aberration, and Magical Ideation, and assessed psychopathology using the Hopkins Symptom Checklist -90 Revised.

RESULTS

Compared to controls, the FHR-AFF sample was significantly impaired in auditory vigilance, while the FHR-SCZ sample was significantly worse in working memory. Both FHR groups showed significantly higher levels of physical anhedonia and some psychopathological dimensions than controls. Adjusting for physical anhedonia, phobic anxiety, depression, psychoticism, and obsessive-compulsive symptoms eliminated the FHR-AFF vigilance effects but not the working memory deficits in FHR-SCZ.

CONCLUSIONS

The working memory deficit in FHR-SZ was the more robust of the cognitive impairments after accounting for psychopathological confounds and is supported as an endophenotype. Examination of larger samples of people at familial risk for different psychoses remains necessary to confirm these findings and to clarify the role of vigilance in FHR-AFF. (JINS, 2016, 22, 1026-1037).

Involvement of NRN1 gene in schizophrenia-spectrum and bipolar disorders and its impact on age at onset and cognitive functioning

OBJECTIVES

Neuritin 1 gene (NRN1) is involved in neurodevelopment processes and synaptic plasticity and its expression is regulated by brain-derived neurotrophic factor (BDNF). We aimed to investigate the association of NRN1 with schizophrenia-spectrum disorders (SSD) and bipolar disorders (BPD), to explore its role in age at onset and cognitive functioning, and to test the epistasis between NRN1 and BDNF.

METHODS

The study was developed in a sample of 954 SSD/BPD patients and 668 healthy subjects. Genotyping analyses included 11 SNPs in NRN1 and one functional SNP in BDNF.

RESULTS

The frequency of the haplotype C-C (rs645649-rs582262) was significantly increased in patients compared to controls (P = 0.0043), while the haplotype T-C-C-T-C-A (rs3763180-rs10484320-rs4960155-rs9379002-rs9405890-rs1475157) was more frequent in controls (P = 3.1 × 10(-5)). The variability at NRN1 was nominally related to changes in age at onset and to differences in intelligence quotient, in SSD patients. Epistasis between NRN1 and BDNF was significantly associated with the risk for SSD/BPD (P = 0.005).

CONCLUSIONS

Results suggest that: (i) NRN1 variability is a shared risk factor for both SSD and BPD, (ii) NRN1 may have a selective impact on age at onset and intelligence in SSD, and (iii) the role of NRN1 seems to be not independent of BDNF.