The neurodevelopmental basis of sex differences in schizophrenia

Prenatal and postnatal influences on behavioral development in a mouse model of preconceptional stress

Depression during pregnancy is detrimental for the wellbeing of the expectant mother and can exert long-term consequences on the offspring's development and mental health. In this context, both the gestational environment and the postpartum milieu may be negatively affected by the depressive pathology. It is, however, challenging to assess whether the contributions of prenatal and postnatal depression exposure are distinct, interactive, or cumulative, as it is unclear whether antenatal effects are due to direct effects on fetal development or because antenatal symptoms continue postnatally. Preclinical models have sought to answer this question by implementing stressors that induce a depressive-like state in the dams during pregnancy and studying the effects on the offspring. The aim of our present study was to disentangle the contribution of direct stress in utero from possible changes in maternal behavior in a novel model of preconceptional stress based on social isolation rearing (SIR). Using a cross-fostering paradigm in this model, we show that while SIR leads to subtle changes in maternal behavior, the behavioral changes observed in the offspring are driven by a complex interaction between sex, and prenatal and postnatal maternal factors. Indeed, male offspring are more sensitive to the prenatal environment, as demonstrated by behavioral and transcriptional changes driven by their birth mother, while females are likely affected by more complex interactions between the pre and the postpartum milieu, as suggested by the important impact of their surrogate foster mother. Taken together, our findings suggest that male and female offspring have different time-windows and behavioral domains of susceptibility to maternal preconceptional stress, and thus underscore the importance of including both sexes when investigating the mechanisms that mediate the negative consequences of exposure to such stressor.

Toll-Like Receptor (TLR) 1, 2, and 6 Gene Polymorphisms Support Evidence of Innate Immune Factors in Schizophrenia

Introduction

Schizophrenia is a complex psychiatric disorder with an important genetic contribution. Immunological abnormalities have been reported in schizophrenia. Toll-like receptor (TLR) genes play an important role in the activation of the innate immune response, which may help to explain the presence of inflammation in people with this disorder. The aim of this study was to analyze the association of TLR1, TLR2, and TLR6 gene polymorphisms in the etiology of schizophrenia.

Methods

We included 582 patients with schizophrenia and 525 healthy controls. Genetic analysis was performed using allelic discrimination with TaqMan probes.

Results

We observed significant differences between patients and controls in the genotype and allele frequencies of TLR1/rs4833093 (χ2 = 17.3, p = 0.0002; χ2 = 15.9, p = 0.0001, respectively) and TLR2/rs5743709 (χ2 = 29.5, p = 0.00001; χ2 = 7.785, p = 0.0053, respectively), and in the allele frequencies of TLR6/rs3775073 (χ2 = 31.1, p = 0.00001). Finally, we found an interaction between the TLR1/rs4833093 and TLR2/rs5743709 genes, which increased the risk of developing schizophrenia (OR = 2.29, 95% CI [1.75, 3.01]).

Discussion

Our findings add to the evidence suggesting that the activation of innate immune response might play an important role in the development of schizophrenia.

A higher dysregulation burden of brain DNA methylation in female patients implicated in the sex bias of Schizophrenia

Sex differences are pervasive in schizophrenia (SCZ), but the extent and magnitude of DNA methylation (DNAm) changes underlying these differences remain uncharacterized. In this study, sex-stratified differential DNAm analysis was performed in postmortem brain samples from 117 SCZ and 137 controls, partitioned into discovery and replication datasets. Three differentially methylated positions (DMPs) were identified (adj.p < 0.05) in females and 29 DMPs in males without overlap between them. Over 81% of these sex-stratified DMPs were directionally consistent between sexes but with different effect sizes. Females experienced larger magnitude of DNAm changes and more DMPs (based on data of equal sample size) than males, contributing to a higher dysregulation burden of DNAm in females SCZ. Additionally, despite similar proportions of female-related DMPs (fDMPs, 8%) being under genetic control compared with males (10%), significant enrichment of DMP-related single nucleotide polymorphisms (SNPs) in signals of genome-wide association studies was identified only in fDMPs. One DMP in each sex connected the SNPs and gene expression of CALHM1 in females and CCDC149 in males. PPI subnetworks revealed that both female- and male-related differential DNAm interacted with synapse-related dysregulation. Immune-related pathways were unique for females and neuron-related pathways were associated with males. This study reveals remarkable quantitative differences in DNAm-related sexual dimorphism in SCZ and that females have a higher dysregulation burden of SCZ-associated DNAm than males.

A Higher Dysregulation Burden of Brain DNA Methylation in Female Patients Implicated in the Sex Bias of Schizophrenia

Sex differences are pervasive in schizophrenia (SCZ), but the extent and magnitude of DNA methylation (DNAm) changes underlying these differences remain uncharacterized. In this study, sex-stratified differential DNAm analysis was performed in postmortem brain samples from 117 SCZ and 137 controls, partitioned into discovery and replication datasets. Three differentially methylated positions (DMPs) were identified (adj. p  < 0.05) in females and 29 DMPs in males without overlap between them. Over 81% of these sex-stratified DMPs were directionally consistent between sexes but with different effect sizes. Down-sampling analysis revealed more DMPs in females than in males when the sample sizes matched. Females had higher DNAm levels in healthy individuals and larger magnitude of DNAm changes in patients than males. Despite similar proportions of female-related DMPs (fDMPs, 8%) being under genetic control compared with males (10%), significant enrichment of DMP-related SNPs in signals of genome-wide association studies was identified only in fDMPs. One DMP in each sex connected the SNPs and gene expression of CALHM1 in females and CCDC149 in males. PPI subnetworks revealed that both female- and male-related differential DNAm interacted with synapse-related dysregulation. Immune-related pathways were unique for females and neuron-related pathways were associated with males. This study reveals remarkable quantitative differences in DNAm-related sexual dimorphism in SCZ and that females have a higher dysregulation burden of SCZ-associated DNAm than males.

Relationship between obsessive compulsive symptomatology and severity of psychotic symptoms in schizophrenia: Meta-analysis and meta-regression analysis

BACKGROUND

Schizophrenia patients often show obsessive-compulsive symptoms (OCS) and obsessive-compulsive disorder (OCD) and their presence has been associated with poorer prognosis. However, the impact of OCS/OCD on psychotic severity remains unclear. The aim of this study is twofold: 1) to investigate the effect of OCS/OCD on the severity of positive, negative, and global psychotic symptoms of schizophrenia patients and 2) to analyze the effect of patient and study-related covariates on moderating this relationship.

METHODS

A systematic review and meta-analysis (SRMA) of studies comparing the severity of psychotic symptoms among schizophrenia patients with and without OCS/OCD was performed. Standardized mean difference (SMD) was calculated for positive, negative, and global psychotic symptoms. The difference of SMD (Diff SMD) was calculated to analyze the effect of covariates on study outcomes using meta-regression.

RESULTS

Sixty-seven studies involving 7740 patients were included. Patients with schizophrenia and OCS/OCD showed a slightly higher severity of positive (SMD = 0.17, p value = 0.0089) and global psychotic symptoms (SMD = 0.24, p value = 0.0104) than patients without OCS/OCD but no differences in negative symptoms were found between groups (SMD = 0.11, p value = 0.0367). Only one covariate "proportion of patients without antipsychotics (AP)" was found to modify the effect on psychotic severity (Diff SMD = -0.008, p value = 0.002).

CONCLUSIONS

Comorbid OCS/OCD in schizophrenia has, at most, a minor impact on psychotic severity. Variability in this effect was considerable and was poorly explained by the covariates analyzed.

Development and validation of a web-based prediction tool on minor physical anomalies for schizophrenia

In support of the neurodevelopmental model of schizophrenia, minor physical anomalies (MPAs) have been suggested as biomarkers and potential pathophysiological significance for schizophrenia. However, an integrated, clinically useful tool that used qualitative and quantitative MPAs to visualize and predict schizophrenia risk while characterizing the degree of importance of MPA items was lacking. We recruited a training set and a validation set, including 463 schizophrenia patients and 281 healthy controls to conduct logistic regression and the least absolute shrinkage and selection operator (Lasso) regression to select the best parameters of MPAs and constructed nomograms. Two nomograms were built to show the weights of these predictors. In the logistic regression model, 11 out of a total of 68 parameters were identified as the best MPA items for distinguishing between patients with schizophrenia and controls, including hair whorls, epicanthus, adherent ear lobes, high palate, furrowed tongue, hyperconvex fingernails, a large gap between first and second toes, skull height, nasal width, mouth width, and palate width. The Lasso regression model included the same variables of the logistic regression model, except for nasal width, and further included two items (interpupillary distance and soft ears) to assess the risk of schizophrenia. The results of the validation dataset verified the efficacy of the nomograms with the area under the curve 0.84 and 0.85 in the logistic regression model and lasso regression model, respectively. This study provides an easy-to-use tool based on validated risk models of schizophrenia and reflects a divergence in development between schizophrenia patients and healthy controls (https://www.szprediction.net/).

Sex and gender associations with indicators of neurodevelopmental compromise in schizophrenia spectrum disorders

BACKGROUND

It has been proposed that sex and gender differences described in schizophrenia can be explained from a neurodevelopmental perspective.

AIM

In this study, we examined the associations of biological sex and gender role endorsement with putative indicators of neurodevelopmental compromise.

METHODS

We used the Bem Sex Role Inventory to calculate masculinity scores in 77 patients with a first episode of a schizophrenia spectrum disorder, and selected the following indicators of neurodevelopmental compromise: family history of schizophrenia, obstetric complications, premorbid functioning, neurological soft signs, and cognitive function. Secondary objectives included the moderating effects of age of onset of illness, substance use and negative symptoms on these associations.

RESULTS

There were no significant sex differences across any of the indicators of neurodevelopmental compromise. However, lower masculinity scores correlated significantly with poorer premorbid adjustment, sensory integration deficits and worse overall cognitive performance. Stepwise linear regression identified poorer premorbid adjustment in early adolescence and lower verbal learning scores as independent predictors of lower masculinity scores. In contrast to sex, gender showed several associations with indicators of neurodevelopmental compromise.

CONCLUSIONS

Lower masculinity scores may represent part of a phenotype for a neurodevelopmental anomaly that places some individuals on a pathway to schizophrenia.

Testing extra-linearity across a psychosis continuum

BACKGROUND

It is unclear whether psychotic experiences (PEs) gradually merge into states of clinical psychosis along a continuum which correspond to a dimensional classification or whether latent classes appear above a certain severity threshold which correspond better to diagnostic categories of psychosis.

METHODS

Annual cross-sectional surveys, 2014-19, among Chinese undergraduates (N = 47,004) measured PEs, depression and etiological risk factors using standardized self-report instruments. We created a psychosis continuum with five levels and tested linear and extra-linear contrasts in associated etiological risk factors, before and after adjustment for depression. We carried out latent class analysis.

RESULTS

Categorical expression of psychosis, including hallucinations and delusions, nuclear symptoms, and nuclear symptoms and depression were found at severe level 5. Etiological risk factors which impacted linearly across the continuum were more common for depression. Child maltreatment impacted extra-linearly on both psychosis and depression. Family history of psychosis impacted linearly on psychosis; male sex and urban birth impacted extra-linearly and were specific for psychosis. Four latent classes were found, but only at level 5. These corresponded to nuclear schizophrenia symptoms, nuclear schizophrenia and depressive symptoms, severe depression, and an unclassified category with moderate prevalence of PEs.

CONCLUSION

Quantitative and qualitative changes in the underlying structure of psychosis were observed at the most severe level along a psychosis continuum, where four latent classes emerged. These corresponded to existing categorical classifications but require confirmation with clinical interview. PEs are non-specific and our findings suggest some are on a continuum with depression, whilst others are on a continuum with non-affective psychosis. Differing patterns of impact from etiological risk factors across the spectrum of psychopathology determine outcome at the most severe level of these continua.

Impact of urban birth and upbringing on expression of psychosis in a Chinese undergraduate population

BACKGROUND

Urban birth and upbringing show consistent associations with psychotic illness but the key urban exposures remain unknown. Associations with psychotic-like experiences (PEs) are inconsistent. These could be confounded by common mental disorders associated with PEs. Furthermore, associations between PEs and urban exposures may not extrapolate to psychotic disorders such as schizophrenia.

METHODS

Annual cross-sectional surveys among first year Chinese undergraduates 2014-2019 (n = 47,004). Self-reported, hierarchical categorisation of psychosis: from psychoticism, paranoid ideation, schizotypal symptoms, nuclear syndrome using SCL-90-R, to clinical diagnosis of schizophrenia. Depressive symptoms using PHQ 9. Dissociative symptoms and posttraumatic stress disorder (PTSD) measured using PCL-C. Etiological factors of family history and childhood disadvantage. We studied effects of urban birth, urban living and critical times of exposure in childhood on psychosis phenotypes.

RESULTS

Associations with urbanicity were found only after adjustments for depression. Urban birth was associated with paranoia (AOR 1.34, 1.18-1.53), schizotypal symptoms (AOR 1.59, 1.29-1.96), and schizophrenia (AOR 2.07, 1.10-3.87). The same phenotypes showed associations with urban residence > 10 years. Only schizophrenia showed an association with urban exposure birth-3 years (AOR 7.01, 1.90-25.86). Child maltreatment was associated with both psychosis and depression. Urbanicity measured across the total sample did not show any associations with demography, family history of psychosis, or child maltreatment. Sensitivity analysis additionally adjusting for dissociative symptoms and PTSD showed the same pattern of findings.

CONCLUSIONS

Urban birth and urban living showed a hierarchical pattern of increasing associations from paranoid ideation to schizotypal disorder to schizophrenia, confirming that associations for psychotic experiences could be extrapolated to schizophrenia, but only after adjusting for confounding from depression, dissociative symptoms and PTSD. Several etiological factors were the same for psychosis and depression. Future studies of PEs should adjust for confounding from common mental disorders and dissociative symptoms. Effects of urbanicity on psychosis were not explained by demography, family history of mental disorder, or child maltreatment.

Genetic Modulators of Traumatic Brain Injury in Animal Models and the Impact of Sex-Dependent Effects

Traumatic brain injury (TBI) is a major health problem causing disability and death worldwide. There is no effective treatment, due in part to the complexity of the injury pathology and factors affecting its outcome. The extent of brain injury depends on the type of insult, age, sex, lifestyle, genetic risk factors, socioeconomic status, other co-injuries, and underlying health problems. This review discusses the genes that have been directly tested in TBI models, and whether their effects are known to be sex-dependent. Sex differences can affect the incidence, symptom onset, pathology, and clinical outcomes following injury. Adult males are more susceptible at the acute phase and females show greater injury in the chronic phase. TBI is not restricted to a single sex; despite variations in the degree of symptom onset and severity, it is important to consider both female and male animals in TBI pre-clinical research studies.

Rates of Neuropsychiatric Disorders and Gestational Age at Birth in a Danish Population

IMPORTANCE

Nonoptimal gestational durations could be associated with neurodevelopmental disabilities, yet evidence regarding finer classification of gestational age and rates of multiple major neuropsychiatric disorders beyond childhood is limited.

OBJECTIVE

To comprehensively evaluate associations between 6 gestational age groups and rates of 9 major types and 8 subtypes of childhood and adult-onset neuropsychiatric disorders.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study evaluated data from a nationwide register of singleton births in Denmark from January 1, 1978, to December 31, 2016. Data analyses were conducted from October 1, 2019, through November 15, 2020.

EXPOSURES

Gestational age subgroups were classified according to data from the Danish Medical Birth Register: very preterm (20-31 completed weeks), moderately preterm (32-33 completed weeks), late preterm (34-36 completed weeks), early term (37-38 completed weeks), term (39-40 completed weeks, reference), and late or postterm (41-45 completed weeks).

MAIN OUTCOMES AND MEASURES

Neuropsychiatric diagnostic records (International Statistical Classification of Diseases and Related Health Problems, Tenth Revision codes F00-F99) were ascertained from the Danish Psychiatric Central Register up to August 10, 2017. Poisson regression was used to estimate the incidence rate ratio (IRR) and 95% CI for neuropsychiatric disorders, adjusting for selected sociodemographic factors.

RESULTS

Of all 2 327 639 singleton births studied (1 194 925 male newborns [51.3%]), 22 647 (1.0%) were born very preterm, 19 801 (0.9%) were born moderately preterm, 99 488 (4.3%) were born late preterm, 388 416 (16.7%) were born early term, 1 198 605 (51.5%) were born at term, and 598 682 (25.7%) were born late or postterm. A gradient of decreasing IRRs was found from very preterm to late preterm for having any or each of the 9 neuropsychiatric disorders (eg, very preterm: IRR, 1.49 [95% CI, 1.43-1.55]; moderately preterm: IRR, 1.23 [95% CI, 1.18-1.28]; late preterm: IRR, 1.17 [95% CI, 1.14-1.19] for any disorders) compared with term births. Individuals born early term had 7% higher rates (IRR, 1.07 [95% CI, 1.06-1.08]) for any neuropsychiatric diagnosis and a 31% higher rate for intellectual disability (IRR, 1.31 [95% CI, 1.25-1.37]) compared with those born at term. The late or postterm group had lower IRRs for most disorders, except pervasive developmental disorders, for which the rate was higher for postterm births compared with term births (IRR, 1.06 [95% CI, 1.03-1.09]).

CONCLUSIONS AND RELEVANCE

Higher incidences of all major neuropsychiatric disorders were observed across the spectrum of preterm births. Early term and late or postterm births might not share a homogeneous low risk with individuals born at term. These findings suggest that interventions that address perinatal factors associated with nonoptimal gestation might reduce long-term neuropsychiatric risks in the population.

Inhibition of mechanistic target of rapamycin signaling decreases levels of O-GlcNAc transferase and increases serotonin release in the human placenta

Changes in placental function, in particular down-regulation of placental O-linked N-acetylglucosamine (O-GlcNAc) transferase (OGT) in response to maternal stress and increased placental secretion of serotonin into the fetal circulation following maternal infection, have been mechanistically linked to adverse neurodevelopment in mice. We hypothesized that mechanistic target of rapamycin (mTOR) signaling is a key regulator of trophoblast serotonin synthesis and OGT protein expression and that serotonin is secreted by the human placenta into the fetal circulation. Placental homogenates (n=46) from elective terminations at 8-22 weeks of gestation and from healthy-term women were sexed and the protein levels of OGT and enzymes involved in serotonin synthesis was determined. Primary human trophoblast (PHT) cells were isolated from normal term placenta (n=27), cultured and transfected (n=8) with siRNA targeting a scramble sequence (control), raptor (inhibits mTOR Complex 1 (mTORC1)), or rictor (inhibits mTOR Complex 2 (mTORC2)). Subsequently, conditioned media and PHT cell lysates were collected. Free serotonin concentration was measured using ELISA in cell culture media and in platelet-depleted normal term umbilical vein and artery plasma (n=38). Both mTORC1 and mTORC2 inhibition down-regulated OGT levels in PHT cells. The level of serotonin synthesis enzyme tryptophan hydroxylase (TPH-1) was higher in early gestation female placentas and at term serotonin concentration was three-fold higher in the umbilical vein than in the umbilical artery. Inhibition of mTORC2, but not mTORC1, increased cultured PHT cell serotonin secretion. Our data are consistent with the model that mTOR signaling is a key regulator of trophoblast serotonin synthesis and OGT protein expression.

Confirming diagnostic categories within a depression continuum: Testing extra-linearity of risk factors and a latent class analysis

BACKGROUND

Dimensions are recommended as replacements for diagnostic categories of depression, but clinicians continue to use categories. Categories are appropriate if major, underlying changes in symptom structure occur above a clinical cut-off on a depression continuum.

METHODS

Cross-sectional surveys of Chinese undergraduates (n = 39,446) 2014-2018 measured self-reported depressive symptoms, associated psychopathology and etiological risk factors using standardised instruments. We created a continuum using PHQ-9 scores and tested linear and extra-linear contrasts in associated psychopathology, and etiology. We carried out latent class analyses (LCA).

RESULTS

Most symptoms showed linear increase, but depressed mood, anhedonia, and suicidal ideation showed marked increase at the severe end of the continuum. There was extra-linear increase in associated psychotic symptoms, other psychopathology, age, low family income, chronic pain and physical illness, childhood physical and sexual abuse, and neglect. Four LCs corresponding to Melancholic, Severe melancholic, Non-melancholic, and Mild depression were confirmed, but only above a clinical cut-off along the continuum. Etiological risk factors did not differentiate between classes but showed overall dramatic increase in impact above threshold of clinical severity.

LIMITATIONS

Only one self-report instrument was used (PHQ-9) to measure depression and diagnoses were not validated by clinical interviews.

CONCLUSIONS

Categories are necessary to describe the dramatic changes in underlying structure and symptom associations above a clinical threshold of severity. These result from extra-linear impact of etiological risk factors at the severe end of the depression continuum. Although the study confirmed melancholic and non-melancholic subtypes, further investigation should investigate etiological factors that determine this subdivision.

Examining which factors influence age of onset in males and females with schizophrenia

OBJECTIVE

Data from the 2010 Australian National Survey of High Impact Psychosis (SHIP) was used to examine (1) what variables influence age of onset (AOO) for males and females, and (2) whether influencing variables were different between the sexes.

METHOD

Data from 622 schizophrenia patients in the SHIP sample was used. These included early life factors, encompassing family psychiatric history, childhood development, trauma and parental loss. Factors occurring within 12 months of diagnosis were also used, including drug/alcohol abuse and premorbid work and social adjustment. Based on the recognised differences in symptom profiles and AOO between the sexes, these factors were regressed separately for males and females.

RESULTS

Stepwise linear regressions showed that a family history of psychiatric disorders was significantly associated with earlier AOO in both sexes. Other variables differed between males and females. Specifically, for females, an earlier AOO was associated with poor premorbid social adjustment and the loss of a family member in childhood. Older AOO was associated with immigrant status. For males, a younger AOO was associated with unemployment at onset, poor premorbid work adjustment, parental divorce in childhood, and lifetime cannabis use. A higher premorbid IQ was associated with an older AOO.

CONCLUSION

Familial predisposition to psychiatric illness is related to earlier AOO of schizophrenia independent of sex. Males appear to have more individual-based predictive factors while females seem to have more community/social-based influences. Future directions for research in schizophrenia are suggested.

Characterizing the Complexity of Weighted Networks via Graph Embedding and Point Pattern Analysis

We propose a new metric to characterize the complexity of weighted complex networks. Weighted complex networks represent a highly organized interactive process, for example, co-varying returns between stocks (financial networks) and coordination between brain regions (brain connectivity networks). Although network entropy methods have been developed for binary networks, the measurement of non-randomness and complexity for large weighted networks remains challenging. We develop a new analytical framework to measure the complexity of a weighted network via graph embedding and point pattern analysis techniques in order to address this unmet need. We first perform graph embedding to project all nodes of the weighted adjacency matrix to a low dimensional vector space. Next, we analyze the point distribution pattern in the projected space, and measure its deviation from the complete spatial randomness. We evaluate our method via extensive simulation studies and find that our method can sensitively detect the difference of complexity and is robust to noise. Last, we apply the approach to a functional magnetic resonance imaging study and compare the complexity metrics of functional brain connectivity networks from 124 patients with schizophrenia and 103 healthy controls. The results show that the brain circuitry is more organized in healthy controls than schizophrenic patients for male subjects while the difference is minimal in female subjects. These findings are well aligned with the established sex difference in schizophrenia.

Cavum septum pellucidum and adhesio interthalamica in schizophrenia: an MRI study

Several studies have independently suggested that patients with schizophrenia are more likely to have an enlarged cavum septum pellucidum (CSP) and an absent adhesio interthalamica (AI), respectively. However, neither finding has been consistently replicated and it is unclear whether there is an association between these two midline brain abnormalities. Thus, we compared the prevalence of absent AI and the prevalence, size and volume of CSP in 38 patients with schizophrenia and 38 healthy controls using magnetic resonance imaging (MRI). There were no between group differences in the presence or volume of CSP; however, an enlarged CSP was commoner among patients than controls. There was also a positive correlation between CSP ratings and volumes. No differences in the presence or absence of the AI were found between patients and controls; however, an absent AI was commoner in male patients with schizophrenia than females. There was absolutely no overlap between the presence of a large CSP and an absence of AI. In conclusion, our findings are in line with several case series and other MRI investigations that have shown a higher incidence of putatively developmental brain abnormalities in patients with schizophrenia, particularly in males, and support the neurodevelopmental model of this disorder.

Follow-up studies of schizophrenia I: Natural history and non-psychopathological predictors of outcome

Treatment-resistant schizophrenia does not exist as a discrete entity, so separating patients who will fail to respond to traditional antipsychotics from those who will respond is impossible with 100% accuracy. However, several predictors of poor clinical outcome have emerged from recent research and knowledge of the processes that lead to poor outcome has become increasingly important with the advent of atypical antipsychotics that may be used in patients with treatment-resistant illness. Much of the variation in outcome can be understood in terms of differences in sample selection, outcome definition and stringency of the diagnostic criteria used. Failure to appreciate these mechanisms may lead to over- or underestimation of the proportion of patients with poor treatment response in clinical and research settings. The importance of factors that predict poor outcome should be judged in terms of their effect size and the degree to which alternative explanations for the association with outcome have been excluded. Although much current research is being focused on specific biological predictors, baseline demographic and illness-related factors, such as ethnic group, sex, social class, type of onset, age of onset and concurrent misuse of alcohol or drugs, have large effects on outcome. Although duration of untreated psychosis before first contact with services may independently predict poor outcome, confounding by variables that are associated with both pathways to care and clinical outcome has not been excluded.

Analysis of the seasonal variation of schizophrenic births using a Kolmogorov-Smirnov type statistic

Previous studies have shown that schizophrenic patients are more likely to be born in winter or early spring months than the general population. Data on 4,207 patients with a hospital diagnosis of schizophrenia were obtained from a mailed survey to public departments of adult psychiatry in metropolitan France. For each year from 1900 to 1965, the expected monthly number of schizophrenic births was calculated and any seasonal variation of live births in the general population was taken into account. Cumulative distributions of the observed and expected number of schizophrenic births were compared using a Kolmogorov-Smirnov type statistic. The seasonal distribution of schizophrenic births was significantly different from that of the general population (P < 0.01). An excess of schizophrenic births was found in the first half of the year, with a peak in April (+ 13%).

What do we know about the aetiology of late-onset schizophrenia?

Late-onset schizophrenia remains an understudied area. Neuroimaging techniques, which have been widely employed in the study of earlier-onset schizophrenic patients, have only recently been applied to patients with a later onset of illness. This paper reviews current knowledge about brain abnormalities in late-onset schizophrenia, and attempts an integration of the findings with clinical, genetic and epidemiological factors which pertain in such disorders. Suggestions are made for future research regarding this group of patients.

Schizophrenic patients: physical health and access to somatic care

This study concerns the state of physical health and the availability of somatic care for 3,470 adult patients diagnosed as schizophrenic according to the research criteria established by the International Classification of Diseases (ICD-10 F20) and treated in public institutions. These institutions volunteered to participate in the study, whereas the patients were selected at random. Data concerning demographic characteristics, physical health, and access to somatic care are compared to that of a public health survey of a sample of the French population. The present study allows the estimation of ratios for a large number of diseases and of some risk factors among the target group. Heavy smokers and overweight individuals are more numerous among schizophrenics. Pathologies such as epilepsy, diabetes and AIDS infection are overrepresented. Patients' access to somatic care is more prevalent than that of the general population overall, similar to that of the less qualified workers or unemployed group. In this study, gender does not appear to allow prediction of care use for schizophrenics in contrast to the general population.

Maternal cortisol during pregnancy and offspring schizophrenia: Influence of fetal sex and timing of exposure

INTRODUCTION

Maternal stress during pregnancy has been repeatedly linked to increased risk for schizophrenia; however, no study has examined maternal cortisol during pregnancy and risk for the disorder. Study aims were to determine whether prenatal cortisol was associated with risk for schizophrenia and risk for an intermediate phenotype-decreased fetal growth-previously linked to prenatal cortisol and schizophrenia. Timing of exposure and fetal sex also were examined given previous findings.

METHODS

Participants were 64 cases diagnosed with schizophrenia spectrum disorders (SSD) and 117 controls from a prospective birth cohort study. Maternal cortisol was determined from stored sera from each trimester and psychiatric diagnoses were assessed from offspring using semi-structured interviews and medical records review.

RESULTS

Maternal cortisol during pregnancy was not associated with risk for offspring schizophrenia. There was a significant interaction between 3rd trimester cortisol and case status on fetal growth. Specifically, cases exposed to higher 3rd trimester maternal cortisol had significantly decreased fetal growth compared to controls. In addition, these findings were restricted to male offspring.

CONCLUSIONS

Our results indicate that higher prenatal cortisol is associated with an intermediate phenotype linked to schizophrenia, fetal growth, but only among male offspring who developed schizophrenia. Findings were consistent with evidence that schizophrenia genes may disrupt placental functioning specifically for male fetuses, as well as findings that males are more vulnerable to maternal cortisol during pregnancy. Finally, results suggest that examining fetal sex and intermediate phenotypes may be important in understanding the mechanisms involved in prenatal contributors to schizophrenia.

The Incidence of Nonaffective, Nonorganic Psychotic Disorders in Older People: A Population-based Cohort Study of 3 Million People in Sweden

BACKGROUND

There are limited data on the epidemiology of very late-onset schizophrenia-like psychosis (VLOSLP) and how this relates to potential risk factors including migration, sensory impairment, traumatic life events, and social isolation.

METHODS

We followed up a cohort of 3 007 378 people living in Sweden, born 1920-1949, from their 60th birthday (earliest: January 15, 1980) until December 30 2011, emigration, death, or first recorded diagnosis of nonaffective psychosis. We examined VLOSLP incidence by age, sex, region of origin, income, partner or child death, birth period, and sensory impairments.

RESULTS

We identified 14 977 cases and an overall incidence of 37.7 per 100 000 person-years at-risk (95% CI = 37.1-38.3), with evidence that rates increased more sharply with age for women (likelihood ratio test: χ2(6) = 31.56, P < .001). After adjustment for confounders, rates of VLOSLP were higher among migrants from Africa (hazard ratio [HR] = 2.0, 95% CI = 1.4-2.7), North America (HR = 1.4, 95% CI = 1.0-1.9, P = .04), Europe (HR = 1.3, 95% CI = 1.2-1.4), Russian-Baltic regions (HR = 1.6, 95% CI = 1.4-1.9), and Finland (HR = 1.6, 95% CI = 1.5-1.7). VLOSLP risk was highest for those in the lowest income quartile (HR = 3.1, 95% CI = 2.9-3.3). Rates were raised in those whose partner died 2 years before cohort exit (HR = 1.1, 95% CI = 1.0-1.3, P = .02) or whose child died in infancy (HR = 1.2, 95% CI = 1.0-1.4, P = .05), those without a partner (HR = 1.9, 95% CI = 1.8-1.9) or children (HR = 2.4, 95% CI = 2.3-2.5), and those whose child had a psychotic disorder (HR = 2.4, 95% CI = 2.2-2.6).

INTERPRETATION

We identified a substantial burden of psychosis incidence in old age, with a higher preponderance in women and most migrant groups. Life course exposure to environmental factors including markers of deprivation, isolation, and adversity were associated with VLOSLP risk.

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.

Gender differences in correlates of cognition in first-episode psychosis

Studies of gender cognitive differences in schizophrenia have reported mixed results. This study examined cognitive correlates including demographics, symptoms and functioning in men and women in a large sample of first-episode adult-onset psychosis patients. Detailed demographic, clinical and functioning data were collected from 360 first-episode patients upon admission into an early intervention service for psychotic disorders. They were also administered a comprehensive neurocognitive battery. Correlation analyses showed that memory and working memory were more significantly associated with onset age, negative symptoms and side effects in women. Processing speed correlated with antipsychotic dosage in men and side effects in women. Selective attention correlated with reality distortion and negative symptoms in women, and onset age and education in men. Executive function correlated with onset age and reality distortion in women. All cognitive domains significantly correlated with educational level and functioning in both genders. Negative symptoms explained significant variability in cognition in both genders, while reality distortion, side effects and affective symptoms were significant factors that differentiated between genders. Although there are similarities in cognitive deficits, considerable heterogeneity exists in associations of symptoms and cognition in men and women. Results facilitate individualised tailoring of interventions, including cognitive remediation therapy.

Dopamine: Functions, Signaling, and Association with Neurological Diseases

The dopaminergic system plays important roles in neuromodulation, such as motor control, motivation, reward, cognitive function, maternal, and reproductive behaviors. Dopamine is a neurotransmitter, synthesized in both central nervous system and the periphery, that exerts its actions upon binding to G protein-coupled receptors. Dopamine receptors are widely expressed in the body and function in both the peripheral and the central nervous systems. Dopaminergic signaling pathways are crucial to the maintenance of physiological processes and an unbalanced activity may lead to dysfunctions that are related to neurodegenerative diseases. Unveiling the neurobiology and the molecular mechanisms that underlie these illnesses may contribute to the development of new therapies that could promote a better quality of life for patients worldwide. In this review, we summarize the aspects of dopamine as a catecholaminergic neurotransmitter and discuss dopamine signaling pathways elicited through dopamine receptor activation in normal brain function. Furthermore, we describe the potential involvement of these signaling pathways in evoking the onset and progression of some diseases in the nervous system, such as Parkinson's, Schizophrenia, Huntington's, Attention Deficit and Hyperactivity Disorder, and Addiction. A brief description of new dopaminergic drugs recently approved and under development treatments for these ailments is also provided.

Genderwise clinical response of antipsychotics among schizophrenic patients: a prospective observational study from Lahore, Pakistan

OBJECTIVE

The study was aimed to evaluate the gender specific response to adherence and occurrence of side effects among schizophrenic patients in Lahore, Pakistan.

METHODS

A prospective study was performed for a period of 1 year among 180 newly diagnosed schizophrenics, aged 20-60 years to observe the symptoms, medication adherence and side effects. Morisky-Green-Levine Scale was used to evaluate medication adherence, LUNSER for side effects and PANSS to measure positive and negative symptoms. Data were analyzed using SPSS.

RESULTS

Positive symptoms (Male: Baseline 36.14 vs. endpoint 23.58, Female: 35.29 vs. 23.74) and negative symptoms (Males 27.9 vs. 20.05, Females 28.41 vs. 20.2) of schizophrenia were equally reduced after a follow up of 1 year in both the genders. Male population suffered more accumulative side effects (11.4 in males vs. 6.40 in females), extrapyramidal symptoms such as tardive dyskinesia and tremors (1.21 in males vs. 0.57 in females) and other side effects as compared to women (p ≤ .005). Males were found poorly adherent to antipsychotic treatment than females (93.3% in males vs. 6.7% in females (p ≤ .005).

CONCLUSIONS

Prescribing practices should not overlook sex specific factors like hormonal changes, altered brain morphology and socioeconomic factors that may be responsible for the difference in the response to the course of schizophrenia.

Early Motor Developmental Milestones and Schizotypy in the Northern Finland Birth Cohort Study 1966

Delayed motor developmental milestones have been reported to be associated with schizophrenia in previous studies, but no study has examined the relationship between early motor developmental milestones and schizotypy. We have examined this relationship in a prospective birth cohort.In the Northern Finland Birth Cohort 1966, data on 9 early motor developmental milestones were collected prospectively from visits to child welfare centers, and data on adult schizotypy were collected through a questionnaire (N = 4557-4674). Positive schizotypy was measured by the Perceptual Aberration Scale (PAS), negative schizotypy was measured by Physical Anhedonia Scale (PhAS) and Social Anhedonia Scale (SAS). Three related scales were included: Schizoidia Scale (SCHD), Hypomanic Personality Scale (HPS), and Bipolar II Scale (BIP2). We examined the milestone-schizotypy associations before and after excluding cases of schizophrenia from this population-based sample. Hierarchical regression analyses adjusted for covariates and separately for both genders were performed. In men, each extra month of delay in achievement of touching thumb with index finger, sitting unsupported, standing up, walking with support, or walking unsupported was associated with an increase in PAS, PhAS, or SCHD scores, or decrease in BIP2 score (P < .05). In women, each extra month of delay in achievement of turning from back to tummy was associated with an increase in PhAS and SAS scores (P < .05). Schizotypy is associated with delayed motor developmental milestones in early-life, but there is some heterogeneity with regards to types of milestones and gender. These findings suggest delayed motor development confers risk across the continuum of schizophrenia syndrome.

The incidence of very late-onset psychotic disorders: a systematic review and meta-analysis, 1960-2016

A substantial subset of people with psychotic disorders are first diagnosed in old age, yet little is known about the epidemiology of very late-onset schizophrenia-like psychosis. We investigated the incidence of affective and non-affective psychotic disorders in those aged 65 and above, and examined variation related to potential risk factors via systematic literature review. We searched PubMed, PsychInfo, Web of Science and bibliographies and directly contacted authors to obtain citations published between 1960 and 2016 containing (derivable) incidence data. Cases were those diagnosed with non-organic psychotic disorders after age 65. Findings were presented narratively, and random-effects meta-analyses were used to obtain pooled incidence rates. From 5687 citations, 41 met inclusion criteria. The pooled incidence of: affective psychoses was 30.9 per 100 000 person-years at risk (100 kpy) [95% confidence interval (CI) 11.5-83.4; I2 = 0.99], and schizophrenia was 7.5 per 100 kpy (95% CI 6.2-9.1; I2 = 0.99), with some evidence of higher schizophrenia rates in women [odds ratio (OR) = 1.6; 95% CI 1.0-2.5, p = 0.05]. We found narrative evidence of increasing incidence rates of non-affective psychoses with age, and higher rates amongst migrants than baseline populations, but no evidence that incidence varied by study quality or case ascertainment period (quality OR = 1.04; 95% CI 0.74-1.48; time period OR = 1.00; 95% CI 0.95-1.05). Substantial heterogeneity in the incidence of very late-onset schizophrenia-like psychoses was observed. No identified studies examined possible risk factors which may account for such variation, including socio-economic status, sensory impairment, traumatic life events, or social isolation.

Placental H3K27me3 establishes female resilience to prenatal insults

Although sex biases in disease presentation are well documented, the mechanisms mediating vulnerability or resilience to diseases are unknown. In utero insults are more likely to produce detrimental health outcomes for males versus females. In our mouse model of prenatal stress, male offspring experience long-term dysregulation of body weight and hypothalamic pituitary adrenal stress axis dysfunction, endophenotypes of male-biased neurodevelopmental disorders. Placental function is critical for healthy fetal development, and we previously showed that sex differences in placental O-linked N-acetylglucosamine transferase (OGT) mediate the effects of prenatal stress on neurodevelopmental programming. Here we show that one mechanism whereby sex differences in OGT confer variation in vulnerability to prenatal insults is by establishing sex-specific trophoblast gene expression patterns and via regulation of the canonically repressive epigenetic modification, H3K27me3. We demonstrate that high levels of H3K27me3 in the female placenta create resilience to the altered hypothalamic programming associated with prenatal stress exposure.

Sex differences in placental O-linked N-acetylglucosamine transferase (OGT) activity mediate the effects of prenatal stress on neurodevelopmental programming. Here authors provide evidence that OGT confers variation in vulnerability to prenatal insults by establishing sex-specific trophoblast gene expression via regulation of H3K27me3.

Influence of Venus and Mars in the cognitive sky of schizophrenia. Results from the first-step national FACE-SZ cohort

OBJECTIVES

Sex differences can yield important clues regarding illness pathophysiology and its treatment. Schizophrenia (SZ) has a lower incidence rate, and a better prognosis, in women versus men. The present study investigated the cognitive profiles of both sexes in a large multi-centre sample of community-dwelling SZ patients.

METHOD

544 community-dwelling stable SZ subjects (141 women and 403 men; mean age 34.5±12.1 and 31.6±8.7years, respectively) were tested with a comprehensive battery of neuropsychological tests.

RESULTS

Although community-dwelling SZ men had more risk factors for impaired cognition (including first-generation antipsychotics administration and comorbid addictive disorders), women had lower scores on a wide range of cognitive functions, including current and premorbid intellectual functioning, working memory, semantic memory, non-verbal abstract thinking and aspects of visual exploration. However, women scored higher in tests of processing speed and verbal learning, as well as having a lower verbal learning bias. No sex difference were evident for visuospatial learning abilities, cued verbal recall, sustained attention and tests of executive functions, including cognitive flexibility, verbal abstract thinking, verbal fluency and planning abilities.

CONCLUSION

Sex differences are evident in the cognitive profiles of SZ patients. The impact on daily functioning and prognosis, as well as longitudinal trajectory, should be further investigated in the FACE-SZ follow-up study. Sex differences in cognition have implications for precision-medicine determined therapeutic strategies.

LIMITS

Given the restricted age range of the sample, future research will have to determine cognitive profiles across gender in late onset SZ.

Needs of women patients with mental illness

Women patients suffer from a range of mental disorders similar to those that men may experience. However, there are some striking differences in the prevalence of specific disorders, and in their presentation and management. Some mental illnesses only occur in women. It seems that women patients may have a different experience of treatment, a consequence of differences in their needs and also of the way that health professionals perceive those needs. These differences are embedded in the wider cultural milieu in which we live. There are particular issues for women patients in relation to, for example, childhood sexual abuse, rape and domestic violence. At present, tools to measure needs of individual patients are generally not gender specific.

Adolescent schizophrenia

Schizophrenia is a devastating chronic disorder that typically presents in early adult life and impacts on a broad swathe of social and psychological functioning. It is not surprising that psychiatrists have tended to be circumspect about making this ominous diagnosis in children and adolescents. Genuine concerns about the validity of applying ‘adult’ psychotic diagnoses in this young age group, together with the lack of diagnosis-specific interventions, have suggested a cautious approach to diagnosis. Furthermore, the relative rarity of schizophrenia in this age group has meant that most psychiatrists have relatively little experience with ‘atypical’ early presentation of the disorder.

Sex and Diffusion Tensor Imaging of White Matter in Schizophrenia: A Systematic Review Plus Meta-analysis of the Corpus Callosum

Sex is considered an understudied variable in health research. Schizophrenia is a brain disorder with known sex differences in epidemiology and clinical presentation. We systematically reviewed the literature for sex-based differences of diffusion properties of white matter tracts in schizophrenia. We then conducted a meta-analysis examining sex-based differences in the genu and splenium of the corpus callosum in schizophrenia. Medline and Embase were searched to identify relevant papers. Studies fulfilling the following criteria were included: (1) included individuals with a diagnosis of schizophrenia, (2) included a control group of healthy individuals, (3) included both sexes in the patient and the control groups, (4) used diffusion tensor imaging, and (5) involved analyzing metrics of white matter microstructural integrity. Fractional anisotropy (FA) was used as the measure of interest in the meta-analysis. Of 730 studies reviewed, 75 met the inclusion criteria. Most showed no effect of sex, however, those that did found either that females have lower FA than males, or that the effect of disease in females is larger than that in males. The findings of the meta-analysis in the corpus callosum supported this result. There is a recognized need for studies on schizophrenia with a sufficient sample of female patients. Lack of power undermines the ability to detect sex-based differences. Understanding the sex-specific impact of illness on neural circuits may help inform development of new treatments, and improvement of existing interventions.

In vivo magnetic resonance images reveal neuroanatomical sex differences through the application of voxel-based morphometry in C57BL/6 mice

Behaviorally relevant sex differences are often associated with structural differences in the brain and many diseases are sexually dimorphic in prevalence and progression. Characterizing sex differences is imperative to gaining a complete understanding of behavior and disease which will, in turn, allow for a balanced approach to scientific research and the development of therapies. In this study, we generated novel tissue probability maps (TPMs) based on 30 male and 30 female in vivo C57BL/6 mouse brain magnetic resonance images and used voxel-based morphometry (VBM) to analyze sex differences. Females displayed larger anterior hippocampus, basolateral amygdala, and lateral cerebellar cortex volumes, while males exhibited larger cerebral cortex, medial amygdala, and medial cerebellar cortex volumes. Atlas-based morphometry (ABM) revealed a statistically significant sex difference in cortical volume and no difference in whole cerebellar volume. This validated our VBM findings that showed a larger cerebral cortex in male mice and a pattern of dimorphism in the cerebellum where the lateral portion was larger in females and the medial portion was larger in males. These results are consonant with previous ex vivo studies examining sex differences, but also suggest further regions of interest.

Assessment of Needs: Differences between male and female patients with schizophrenia needs in psychiatric hospitals in Baghdad city

BACKGROUND

Gender differences are one of the most important and crucial subjects in evaluating the nursing care as well as mental health care system for psychiatric patients especially patients with schizophrenia.

AIMS

We aimed to identify differences in needs of male and female patients with schizophrenia in psychiatric hospitals in Baghdad city and its relationship with some variables.

METHOD

A descriptive, analytical design that was carried out by using Camberwell needs assessment, short appraisal schedule, self-report version (CANSAS-P) after translating to Arabic.

RESULTS

Results indicated that there were a lot of unmet needs of male and female patients with schizophrenia, according to the entire CANSAS-P domains especially psychological symptoms. Differences were found in types of needs as the majority of men have more social needs while females was found to be more occupied with their fears and need safety.

CONCLUSION

there were differences in types of need between male and female patients with schizophrenia; needs were affected by some variables such as educational level, first 10 days of admission and family visiting.

Early motor developmental milestones and schizophrenia: A systematic review and meta-analysis

The neurodevelopmental hypothesis of schizophrenia proposes that impaired brain development is a cause of the illness. Early motor developmental milestones, such as learning to walk, are predictors of later schizophrenia but studies have not been systematically reviewed. The aim of the present systematic review and meta-analysis was to explore the association between early motor developmental milestones and the risk of adult schizophrenia. In addition, we updated a systematic review on motor function and risk of schizophrenia. The PubMed, PsycINFO and Scopus databases were searched for original research articles published up to July 2015. Motor milestones were measured between ages 0 and 13years. Random effect meta-analysis calculated effect estimates (Hedges' g) for the association between individual motor milestones and schizophrenia risk. An electronic database and selected articles reference list search identified 5990 articles after removing duplicates. Sixty-nine full text articles were assessed for eligibility of which six were included in the review. Five studies provided sufficient data for meta-analyses. The following motor milestones were significantly associated with adult schizophrenia risk: walking unsupported (g=0.46; 95% CI 0.27-0.64; p<0.001), standing unsupported (g=0.28; 0.16-0.40; p<0.001) and sitting unsupported (g=0.18; 0.05-0.31; p=0.007). Results for the milestones 'holding head up' and 'grabbing object' were not statistically significant. Delayed walking, sitting and standing unsupported were associated with adult onset schizophrenia. The findings emphasise the importance of timely achievement of these motor milestones in childhood and can contribute to the identification of individuals at risk of psychosis.

The placenta and neurodevelopment: sex differences in prenatal vulnerability

Prenatal insults, such as maternal stress, are associated with an increased neurodevelopmental disease risk and impact males significantly more than females, including increased rates of autism, mental retardation, stuttering, dyslexia, and attention deficit/hyperactivity disorder (ADHD). Sex differences in the placenta, which begin with sex chromosomes, are likely to produce sex-specific transplacental signals to the developing brain. Our studies and others have identified X-linked genes that are expressed at higher levels in the female placenta. Through a genome-wide screen after maternal stress in mice, we identified the X-linked gene O-linked N-acetylglucosamine transferase (OGT) and demonstrated its causality in neurodevelopmental programming producing a male-specific stress phenotype. Elucidating the sex-specific molecular mechanisms involved in transplacental signals that impact brain development is key to understanding the sex bias in neurodevelopmental disorders and is expected to yield novel insight into disease risk and resilience.

Neuroimmunology and neuroepigenetics in the establishment of sex differences in the brain

The study of sex differences in the brain is a topic of neuroscientific study that has broad reaching implications for culture, society and biomedical science. Recent research in rodent models has led to dramatic shifts in our views of the mechanisms underlying the sexual differentiation of the brain. These include the surprising discoveries of a role for immune cells and inflammatory mediators in brain masculinization and a role for epigenetic suppression in brain feminization. How and to what degree these findings will translate to human brain development will be questions of central importance in future research in this field.

Typology of people with first-episode psychosis

AIMS

The aim of the current study was to create a typology of patients with first-episode psychosis based on sociodemographic and clinical characteristics, service use and outcomes using cluster analysis.

METHODS

Data from all respondents who were accepted into the Early Psychosis Intervention Programme (EPIP), Singapore from 2007 to 2011 were analysed. A two-step clustering method was carried out to classify the patients into distinct clusters.

RESULTS

Two clusters were identified. Cluster 1 comprised largely of younger people with mean age of 25.5 (6.0) years at treatment contact, who were predominantly male (55.3%), single (98.3%) and living with parents (86.3%). Cluster 1 had a higher proportion of people diagnosed with the schizophrenia spectrum disorder (71.4%) and with a positive family history of psychiatric illness. Patients in cluster 2 were generally older with a mean age of 33.6 (4.7) years and the majority were women (74.2%). Cluster 1 had people with higher Positive and Negative Syndrome Scale (PANSS) scores at baseline as compared with cluster 2. After a 1-year follow up, their scores were still poorer than their counterparts in cluster 2, especially for PANSS negative score. The functioning level of people in cluster 1 showed less improvement than the people in cluster 2 after a year of treatment.

CONCLUSIONS

There is a compelling need to develop new therapies and intensively treat young people presenting with psychosis as this group tends to have poorer outcomes even after 1 year of treatment.

Examining gender difference in adult-onset psychosis in Hong Kong

AIM

Gender-specific treatment strategies for psychosis have been suggested in recent years. Data on gender difference were largely consistent regarding premorbid functioning, age of onset and negative symptoms; however, results regarding neurocognitive function and duration of untreated psychosis were mixed and inconclusive. In this study, we aimed at a thorough examination on the gender differences in 360 Chinese patients with first-episode psychosis in Hong Kong.

METHODS

From June 2009 to August 2011, participants were consecutively recruited from a population-based territory-wide study of early psychosis targeting first-episode psychosis in Hong Kong. Comprehensive data on basic demographics, premorbid functioning and schizoid and schizotypal traits, clinical, functioning, medication side effects and a battery of neurocognitive measures were collected upon entry into the service.

RESULTS

In 360 patients with first-episode psychosis aged between 26 and 55 years, 43.6% (n = 157) were male and 56.4% (n = 203) were female. Males had poorer premorbid functioning and adjustment, earlier age of onset, more negative symptoms and poorer functioning in terms of work productivity, independent living and immediate social network relationships at presentation of first-episode psychosis. Interestingly, our data indicate that males tend to be more educated, and also characterized by higher IQ, better neurocognitive performance on visual domain compared with females. Duration of untreated psychosis was not different between the two genders.

CONCLUSION

Data from this homogeneous cohort of Chinese populations enabled tailored and culturally sensitive recommendation on gender-specific treatment strategies, hence improving patients' care and facilitate better diagnostic and interventional decisions for patients with psychosis.

Gendering psychosis: the illness of Zelda Fitzgerald

Psychiatric textbooks tend to describe psychosis as it is experienced by men. The well-documented illness of Zelda Fitzgerald illustrates the feminine side of psychosis. The distinctive features of Zelda's illness--its specific precipitants, the timing of its onset, the discontinuities in its course, the pronounced mood swings, the preservation of intellect and of agency, the maintenance of human ties, the association of flare-ups with immune and hormonal changes, the responsiveness to treatment, the lifelong creativity and productivity--show the female side of psychotic illness, one that is rarely described in diagnostic manuals. This paper relies on Nancy Milford's biography of Zelda, as well as on several other biographical sources and, using Zelda's own words and the words of her husband and friends, allows entry into a feminine world of psychosis, not encountered in textbooks. The expression of psychotic illness varies from person to person, its exact shape depending on many factors, most of them still undetermined, but gender is a critically important core component of variance.

Fetal exposure to maternal stress and risk for schizophrenia spectrum disorders among offspring: Differential influences of fetal sex

Exposure to adverse life events during pregnancy has been linked to increased risk of schizophrenia spectrum disorders (SSD) in offspring. Nevertheless, much of the previous work inferred maternal stress from severe life events rather than directly assessing maternal reports of stress. The present study aimed to examine maternal reports of stress during pregnancy and risk for offspring SSD. Participants were 95 SSD cases and 206 controls who were offspring from a large birth cohort study that followed pregnant women from 1959 to 1966. During pregnancy interviews, women were asked if anything worrisome had occurred recently. Interviews were qualitatively coded for stress-related themes, including reports of daily life stress, by two independent raters. None of the maternal psychosocial stress themes were significantly associated with increased odds of offspring SSD in analyses of the full sample. However, results indicated a significant daily life stress by infant sex interaction. Maternal daily life stress during pregnancy was associated with significantly increased odds of SSD among male offspring. Findings suggest sex-specific fetal sensitivity to maternal reported daily life stress during pregnancy on risk for SSD, with males appearing to be more vulnerable to the influences of maternal stress during pregnancy.

Neuropsychological correlates of remission in chronic schizophrenia subjects: The role of general and task-specific executive processes

Background

Although cognitive deficits have consistently been characterized as core features of schizophrenia, they have not been incorporated into definitions of remission. Furthermore, just a few studies have examined the relationship between cognitive deficits and symptomatic remission. The main aim of the present study is to evaluate the executive functioning of nonremitted schizophrenia patients.

Methods

72 remitted and 42 nonremitted schizophrenia patients, and 119 healthy controls were examined. Subjects were tested with a comprehensive battery of cognitive tests, including a measure to assess the general components of executive functioning and individual tasks to tap the three specific executive dimensions assessed in the present study, namely updating, shifting and inhibition.

Results

Schizophrenia subjects performed poorly on general executive functioning and shifting tasks in comparison to healthy controls. Remitted subjects performed better than nonremitted on inhibition and updating tasks. Whereas being a male and showing decreases in updating increase the chances of being in the nonremitted schizophrenia subjects group, increases in shifting and updating enhance the odds of being in the healthy control group.

Conclusion

The present findings suggest that executive function deficits are present in chronic schizophrenic patients. In addition, specific executive processes might be associated to symptom remission. Future studies examining prospectively first-episode, drug naive patients diagnosed with schizophrenia may be especially elucidative.

Sex/gender differences in the brain and cognition in schizophrenia

The early conceptualizations of schizophrenia have noted some sex/gender differences in epidemiology and clinical expression of the disorder. Over the past few decades, the interest in differences between male and female patients has expanded to encompass brain morphology and neurocognitive function. Despite some variability and methodological shortcomings, a few patterns emerge from the available literature. Most studies of gross neuroanatomy show more enlarged ventricles and smaller frontal lobes in men than in women with schizophrenia; finding reflecting normal sexual dimorphism. In comparison, studies of brain asymmetry and specific corticolimbic structures, suggest a disturbance in normal sexual dimorphism. The neurocognitive findings are somewhat consistent with this picture. Studies of cognitive functions mediated by the lateral frontal network tend to show sex differences in patients which are in the same direction as those observed in the general population, whereas studies of processes mediated by the corticolimbic system more frequently reveal reversal of normal sexual dimorphisms. These trends are faint and future research would need to delineate neurocognitive differences between men and women with various subtypes of schizophrenia (e.g., early versus late onset), while taking into consideration hormonal status and gender of tested participants.

Contribution of sex hormones to gender differences in schizophrenia: A review

Female patients with schizophrenia tend to have a more benign course and better outcomes than males. One proposed explanation is the differential influence of male and female sex hormones, including estrogen, progesterone, testosterone, and dehydroepiandrosterone (DHEA) and its sulfate (DHEAS). Such benefit may be mediated by their effects on neurotransmitters and neuroprotection. Besides altered estrogen and DHEA/DHEAS levels in female patients, data is equivocal on hormonal differences between patients and controls. However, several reports note a mostly negative correlation between estrogen levels and symptom severity in both genders, and a positive correlation between estrogen levels and neurocognition but mainly in females. Adjunctive estrogen appears to improve symptoms in both genders. Progesterone levels have inconsistent links to symptom severity in both genders, and correlate positively with neurocognition but only in males. Estrogen-progesterone combination shows preliminary benefits as augmentation for both symptoms and neurocognition in females. Testosterone levels correlate inversely with negative symptoms in males and have inconsistent associations with neurocognition in both genders. Testosterone augmentation reduced negative symptoms in male patients in a pilot investigation, but has not been evaluated for neurocognition in either gender. DHEA/DHEAS have mixed results for their association with, and clinical utility for, symptoms and neurocognition in both genders. Overall, data on the impact of sex hormones on clinical course or as treatment for schizophrenia is limited, but estrogen has most evidence for positive influence and clinical benefit. The possibly greater tolerability and broader impact of these hormones versus existing medications support further exploration of their use.

Schizophrenia

Schizophrenia is a chronic psychiatric disorder with a heterogeneous genetic and neurobiological background that influences early brain development, and is expressed as a combination of psychotic symptoms - such as hallucinations, delusions and disorganization - and motivational and cognitive dysfunctions. The mean lifetime prevalence of the disorder is just below 1%, but large regional differences in prevalence rates are evident owing to disparities in urbanicity and patterns of immigration. Although gross brain pathology is not a characteristic of schizophrenia, the disorder involves subtle pathological changes in specific neural cell populations and in cell-cell communication. Schizophrenia, as a cognitive and behavioural disorder, is ultimately about how the brain processes information. Indeed, neuroimaging studies have shown that information processing is functionally abnormal in patients with first-episode and chronic schizophrenia. Although pharmacological treatments for schizophrenia can relieve psychotic symptoms, such drugs generally do not lead to substantial improvements in social, cognitive and occupational functioning. Psychosocial interventions such as cognitive-behavioural therapy, cognitive remediation and supported education and employment have added treatment value, but are inconsistently applied. Given that schizophrenia starts many years before a diagnosis is typically made, the identification of individuals at risk and those in the early phases of the disorder, and the exploration of preventive approaches are crucial.

The ratios of 2nd to 4th digit may be a predictor of schizophrenia in male patients

The production of androgens (mostly testosterone) during the early fetal stage is essential for the differentiation of the male brain. Some authors have suggested a relationship between androgen exposure during the prenatal period and schizophrenia. These two separate relationships suggest that digit length ratios are associated with schizophrenia in males. The study was performed in a university hospital between October 2012 and May 2013. One hundred and three male patients diagnosed with schizophrenia according to DSM-IV using SCID-I, and 100 matched healthy males, were admitted to the study. Scale for the Assessment of Positive Symptoms (SAPS), Scale for the Assessment of Negative Symptoms (SANS) and Brief Psychiatric Rating Scale (BPRS) were used to assess schizophrenia symptoms. The second digit (2D) and fourth digit (4D) asymmetry index (AI), and the right- and left-hand 2D:4D ratios were calculated. All parametric data in the groups were compared using an independent t-test. The predictive power of the AI was estimated by receiver operating characteristics analysis. The 2D:4D AI was statistically significantly lower in the patient group than the healthy control comparison group. There were significant differences between the schizophrenia and the control groups in respect of left 2D:4D and right 2D:4D. There was no correlation between AI, left, or right 2D:4D, BPRS, or SAPS in the schizophrenia group. However, there was a negative correlation between left 2nd digit (L2D):4D and the SANS score. Our findings support the view that the 2D:4D AI can be used as a moderate indicator of schizophrenia. Even more simply, the right or left 2D:4D can be used as an indicator. L2D:4D could indicate the severity of negative symptoms.