Testing the neurodevelopmental, trauma and developmental risk factor models of psychosis using a naturalistic experiment

N2 Responses in Youths With Psychosis Risk Syndrome and Their Association With Clinical Outcomes: A Cohort Follow-Up Study Based on the Three-Stimulus Visual Oddball Paradigm

OBJECTIVE

Schizophrenia often occurs during youth, and psychosis risk syndrome occurs before the onset of psychosis. The aim of this study was to determine whether the visual event-related potential responses in youths with psychosis risk syndrome were defective in the presence of interference stimuli and associated with their clinical outcomes.

METHODS

A total of 223 participants, including 122 patients with psychosis risk syndrome, 50 patients with emotional disorders, and 51 healthy control subjects, were assessed. Baseline EEG was recorded during the three-stimulus visual oddball task. The event-related potentials induced by square pictures with different colors were measured. Almost all patients with psychosis risk syndrome were followed up for 12 months and were reclassified into three subgroups: conversion, symptomatic, and remission. The differences in baseline event-related potential responses were compared among the clinical outcome subgroups.

RESULTS

The average N2 amplitude of the psychosis risk syndrome group was significantly less negative than that in the healthy control group (d=0.53). The baseline average N2 amplitude in the conversion subgroup was significantly less negative than that in the symptomatic (d=0.58) and remission (d=0.50) subgroups and in the healthy control group (d=0.97). The average N2 amplitude did not differ significantly between the symptomatic and remission subgroups (d=0.02). However, it was significantly less negative in the symptomatic and remission subgroups than in the healthy control group (d=0.46 and d=0.38). No statistically significant results were found in the P3 response.

CONCLUSIONS

Youths with psychosis risk syndrome had significant N2 amplitude defects in attention processing with interference stimuli. N2 amplitude shows potential as a prognostic biomarker of clinical outcome in the psychosis risk syndrome.

Understanding the prospective associations between neuro-developmental problems, bullying victimization, and mental health: Lessons from a longitudinal study of institutional deprivation

Studies suggest that children who have experienced neglect are at risk for bullying which in turn increases the risk for poor mental health. Here we extend this research by examining whether this risk extends to the neglect associated with severe institutional deprivation and then testing the extent to which these effects are mediated by prior deprivation-related neuro-developmental problems such as symptoms of inattention, hyperactivity and autism. Data were collected at ages 6, 11, 15, and young adulthood (22-25 years) from 165 adoptees who experienced up to 43 months of deprivation in Romanian Orphanages in 1980s and 52 non-deprived UK adoptees (N = 217; 50.23% females). Deprivation was associated with elevated levels of bullying and neuro-developmental symptoms at ages 6 through 15 and young adult depression and anxiety. Paths from deprivation to poor adult mental health were mediated via cross-lagged effects from earlier neuro-developmental problems to later bullying. Findings evidence how deep-seated neuro-developmental impacts of institutional deprivation can cascade across development to impact social functioning and mental health. These results elucidate cascade timing and the association between early deprivation and later bullying victimization across childhood and adolescence.

Reduced health-related quality of life in children born extremely preterm in 2006 compared with 1995: the EPICure Studies

OBJECTIVE

To compare health-related quality of life (HRQL) in childhood for extremely preterm (EP) births before 26 weeks of gestation in England in two eras: 1995 and 2006.

DESIGN

Prospective cohort studies.

SETTING

School or home-based assessments at 11 years of age.

PARTICIPANTS

Available data for 88 EP children born before 26 weeks of gestation in 2006 (EPICure2) were compared with those of 140 born in England during 1995 (EPICure). To account for social secular trends, the comparison between eras was also made for term-born controls as reference.

MAIN OUTCOME MEASURES

HRQL was measured using the parent-completed Health Utilities Index (HUI) questionnaire with utility scores calculated using the HUI3 classification system. Eight attributes were assessed: vision, hearing, speech, ambulation, dexterity, emotion, cognition and pain.

RESULTS

At 11 years, mean utility scores were significantly lower in EPICure2 (2006) than in EPICure (1995; Δ -0.12, 95% CI -0.20 to -0.04). The difference increased (Δ -0.27, 95% CI -0.41 to -0.12) after adjusting for significant perinatal and demographic differences between cohorts. Rates of suboptimal function were increased in EPICure2 for all eight attributes, but statistically significant differences were only found in speech (p=0.004) and dexterity (p=0.020). After excluding children with severe neurodevelopmental impairment, the adjusted difference between cohorts remained significant but attenuated (-0.14 (-0.26 to -0.01)). Mean utility scores for controls were similar between cohorts (Δ -0.01 (-0.04 to 0.02)).

CONCLUSIONS

Using parent report, there was a clinically significant decline in HRQL ratings for EP children over time. Areas contributing the most to the decline were speech and dexterity.

TRIAL REGISTRATION NUMBER

ISRCTN86323684.

The Role and Clinical Correlates of Complex Post-traumatic Stress Disorder in People With Psychosis

Traumatic experiences and post-traumatic stress are highly prevalent in people with psychosis, increasing symptom burden, decreasing quality of life and moderating treatment response. A range of post-traumatic sequelae have been found to mediate the relationship between trauma and psychotic experiences, including the "traditional" symptoms of post-traumatic stress disorder (PTSD). The International Classification of Diseases-11th Edition recognizes a more complex post-traumatic presentation, complex PTSD (cPTSD), which captures both the characteristic symptoms of PTSD alongside more pervasive post-traumatic sequelae known as 'disturbances in self-organization' (DSOs). The prevalence and impact of cPTSD and DSOs in psychosis remains to be explored. In the first study of this kind, 144 participants with psychosis recruited from North West United Kingdom mental health services completed measures assessing trauma, PTSD and cPTSD symptoms and symptoms of psychosis. Forty-percent of the sample met criteria for cPTSD, compared to 10% who met diagnostic criteria for PTSD. PTSD and DSOs mediated the relationship between trauma and positive symptoms, controlling for dataset membership. Both PTSD and DSOs mediated the relationship between trauma and affective symptoms but did not explain a significant proportion of variance in negative symptoms. Cognitive and excitative symptoms of psychosis did not correlate with trauma, PTSD or DSO scores. These findings indicate the possible value of adjunct therapies to manage cPTSD symptoms in people with psychosis, pending replication in larger epidemiological samples and longitudinal studies.

Prenatal stress and offspring depression in adulthood: The mediating role of childhood trauma

BACKGROUND

There is repeated evidence for a prenatal programming effect for the development of offspring depression. However, examination of environmental influences along this pathway is sparse. This study aimed to investigate the direct and indirect effects of pre- and postnatal stress on offspring depression in adulthood, via increased exposure to childhood trauma.

METHODS

A large longitudinal population-based cohort (N = 3506) was followed up from birth and assessed at 24 years. Diagnosis of depression was derived using the International Classification of Diseases-10th revision (ICD-10). Two separate sources of pre- and postnatal stress were examined - maternal depression and family adversity, and childhood trauma was assessed prospectively across childhood until 17 years.

RESULTS

Both pre- and postnatal maternal depression and family adversity were associated with offspring depression at 24 years in simple logistic regression models. When all pathways were modelled simultaneously, only childhood trauma was directly associated with offspring depression, and mediated all pathways from both sources of pre- and postnatal stress to offspring depression (7-16% of the total effect mediated). Sensitivity analysis on specific trauma found stronger evidence for a mediated pathway via physical, emotional abuse and peer bullying, compared to emotional neglect, sexual abuse and domestic violence.

CONCLUSIONS

These findings indicate that reducing childhood trauma could be a target to decrease depression in the general population, and the focus should also be on families at high risk of experiencing pre- or postnatal stress, to provide them with better support.

Social Functioning in Adults Born Very Preterm: Individual Participant Meta-analysis

CONTEXT

There is a lack of research on individual perceptions of social experiences and social relationships among very preterm (VP) adults compared with term-born peers.

OBJECTIVE

To investigate self-perceived social functioning in adults born VP (<32 weeks' gestation) and/or with very low birth weight (VLBW) (<1500g) compared with term-born adults (≥37 weeks' gestation) using an individual participant data (IPD) meta-analysis.

DATA SOURCES

Two international consortia: Research on European Children and Adults born Preterm and Adults Born Preterm International Collaboration.

STUDY SELECTION

Cohorts with outcomes assessed by using the Adult Self-Report Adaptive Functioning scales (friends, spouse/partner, family, job, and education) in both groups.

DATA EXTRACTION

IPD from 5 eligible cohorts were collected. Raw-sum scores for each scale were standardized as z scores by using mean and SD of controls for each cohort. Pooled effect size was measured by difference (Δ) in means between groups.

RESULTS

One-stage analyses (1285 participants) revealed significantly lower scores for relationships with friends in VP/VLBW adults compared with controls (Δ -0.37, 95% confidence interval [CI]: -0.61 to -0.13). Differences were similar after adjusting for sex, age, and socioeconomic status (Δ -0.39, 95% CI: -0.63 to -0.15) and after excluding participants with neurosensory impairment (Δ -0.34, 95% CI: -0.61 to -0.07). No significant differences were found in other domains.

LIMITATIONS

Generalizability of research findings to VP survivors born in recent decades.

CONCLUSIONS

VP/VLBW adults scored their relationship with friends lower but perceived their family and partner relationships, as well as work and educational experiences, as comparable to those of controls.

Associations Between Language Difficulties, Peer Victimization, and Bully Perpetration From 3 Through 8 Years of Age: Results From a Population-Based Study

Background and Purpose Schoolchildren with language difficulties experience more peer victimization compared to their typically developing (TD) peers. Whether these children also bully their peers (bully perpetration) more than TD children is unclear. Furthermore, little is known about peer victimization and bully perpetration among preschool children with language difficulties and how it may be related to different paths of language difficulties. This study aimed to investigate associations between language difficulties, peer victimization, and bully perpetration from preschool to school age as well as the risk of peer victimization and bully perpetration for children with different developmental paths of language difficulties and mild language difficulties compared to TD children. Method The sample was drawn from the Norwegian Mother, Father and Child Cohort Study. Participants with completed questionnaires at 3, 5, and 8 years of age (n = 22,628) were included. Paths between latent variables of language skills at 3, 5, and 8 years of age, peer victimization at 5 and 8 years of age, and bully perpetration at 8 years of age were examined with structural equation modeling. Logistic regression was used to investigate peer victimization and bully perpetration for predefined paths of language difficulties. Results Poor language skills at 3 and 5 years of age were associated with peer victimization at 5 years of age. Poor language skills at 5 and 8 years of age were associated with peer victimization and bully perpetration at 8 years of age. The association between poor language skills at 5 years of age and bully perpetration at 8 years of age was stronger for girls. Persistent paths of language difficulties at 3, 5, and 8 years of age showed the highest risk of peer victimization and bully perpetration. Conclusions Language difficulties are associated with peer victimization and bully perpetration. The risk of peer victimization and bully perpetration differs according to different developmental paths of language difficulties from preschool to school age.

Extremely preterm birth and autistic traits in young adulthood: the EPICure study

Background

A high prevalence of autism spectrum disorder is reported in children born extremely preterm (EP), but an even larger proportion of survivors are affected by subclinical difficulties than meet diagnostic criteria. The aims of this study were to investigate autistic traits associated with the broader autism phenotype in a cohort of young adults born EP, and explore how these traits relate to emotion recognition, empathy and autism symptom presentation in childhood. The prevalence of autism diagnoses was also investigated.

Methods

One hundred and twenty-nine young adults born before 26 weeks of gestation and 65 term-born controls participated in the 19-year follow-up phase of the EPICure studies. In addition to a clinical interview, participants completed the Broader Autism Phenotype Questionnaire (BAPQ), the Empathy Quotient questionnaire, and the Frankfurt Test and Training of Facial Affect Recognition. The Social Communication Questionnaire (SCQ) was completed by the participants’ parents at age 11 years.

Results

EP born young adults scored significantly higher on the BAPQ in comparison with their term-born peers, indicating greater autistic traits. Among EP participants, BAPQ scores were correlated with SCQ scores in childhood (r = 0.484, p < 0.001). EP young adults had significantly lower scores in emotion recognition and empathy in comparison with controls; however, this effect was mediated by IQ. At 19 years, a diagnosis of autism was reported by 10% of EP participants versus 1.6% of controls, whereas 31% of EP participants scored above the cut-off for the broader autism phenotype in comparison with 8.5% of term-born controls.

Limitations

The high attrition of EP participants from lower socio-economic backgrounds and with lower cognitive functioning may have led to an underrepresentation of those presenting with difficulties associated with autism.

Conclusions

A larger proportion of EP survivors are affected by difficulties associated with autism than have confirmed diagnoses, with a moderate correlation between autism symptom scores in childhood and autistic traits in young adulthood. EP young adults had significantly higher autism symptom scores and a larger proportion had a diagnosis of autism than controls. Screening for autistic traits at set points throughout childhood will help identify those EP individuals at risk of social difficulties who may benefit from intervention.

Supplementary information

The online version contains supplementary material available at 10.1186/s13229-021-00414-0.

Mania symptoms in a Swedish longitudinal population study: The roles of childhood trauma and neurodevelopmental disorders

BACKGROUND

Adult psychiatric disorders are associated with both childhood traumatic experiences (CTEs) and neurodevelopmental disorders (NDDs). CTEs and NDDs frequently co-occur in childhood, but their combined risk effect on the emergence of juvenile mania symptoms has not yet been examined.

METHODS

In a population-representative Swedish twin study, CTEs and NDDs were assessed in 3,348 nine-year old twins born between 1998 and 2001, and treated as dichotomous predictors (any CTEs, any NDDs). Follow-up data were gathered at age 15 through parental reports of mania symptoms, yielding a symptom count score.

RESULTS

Both CTEs and NDDs at age 9 contributed uniquely to an increase in mania symptoms at age 15. Children with both risk factors had 1.6 times the rate of mania symptoms as children with CTEs-only (Incidence rate ratio [IRR] 1.63, 95% CI 1.37-1.93), and 1.3 times the rate of mania symptoms as children with NDDs-only (IRR 1.26, 95% CI 1.06-1.50). There was no evidence for an interactive effect of CTEs and NDDs. NDDs showed a trend towards having a larger effect on mania symptoms than CTEs (NDDs-only vs. CTEs-only: IRR 1.29, 95% CI 0.99-1.68).

LIMITATIONS

Although it is a strength of the study that the data on exposures and outcome were collected prospectively, parental recall of CTEs was required and CTEs may be under-reported.

CONCLUSIONS

NDDs are at least as important as CTEs in the development of mania symptoms, and their risk is additive. Those with a history of both CTEs and NDDs should be monitored closely for the development of more severe psychiatric presentations.

Adolescent Neurodevelopment and Vulnerability to Psychosis

Adolescence is characterized by significant changes in several domains, including brain structure and function, puberty, and social and environmental factors. Some of these changes serve to increase the likelihood of psychosis onset during this period, while others may buffer this risk. This review characterizes our current knowledge regarding the unique aspects of adolescence that may serve as risk factors for schizophrenia spectrum disorders. In addition, we provide potential future directions for research into adolescent-specific developmental mechanisms that impart vulnerability to psychosis and the possibility of interventions that capitalize on adolescents' unique characteristics. Specifically, we explore the ways in which gray and white matter develop throughout adolescence in typically developing youth as well as in those with psychosis spectrum disorders. We also discuss current views on the function that social support and demands, as well as role expectations, play in risk for psychosis. We further highlight the importance of considering biological factors such as puberty and hormonal changes as areas of unique vulnerability for adolescents. Finally, we discuss cannabis use as a factor that may have a unique impact during adolescent neurodevelopment, and subsequently potentially impact psychosis onset. Throughout, we include discussion of resilience factors that may provide unique opportunities for intervention during this dynamic life stage.

Genetic underpinnings of schizophrenia-related electroencephalographical intermediate phenotypes: A systematic review and meta-analysis

Although substantial research into genetics of psychotic disorders has been conducted, a large proportion of their genetic architecture has remained unresolved. Electroencephalographical intermediate phenotypes (EIP) have the potential to constitute a valuable tool when studying genetic risk loci for schizophrenia, in particular P3b amplitude, P50 suppression, mismatch negativity (MMN) and resting state power spectra of the electroencephalogram (EEG). Here, we systematically reviewed studies investigating the association of single nucleotide polymorphisms (SNPs) with these EIPs and meta-analysed them when appropriate. We retrieved 45 studies (N = 34,971 study participants). Four SNPs investigated in more than one study were genome-wide significant for an association with schizophrenia and three were genome-wide suggestive, based on a lookup in the influential 2014 GWAS (Ripke et al., 2014). However, in our meta-analyses, rs1625579 failed to reach a statistically significant association with p3b amplitude decrease and rs4680 risk allele carrier status was not associated with p3b amplitude decrease or with impaired p50 suppression. In conclusion, evidence for SNP associations with EIPs remains limited to individual studies. Careful selection of EIPs and SNPs, combined with consistent reporting of effect sizes, directions of effect and p-values would aid future meta-analyses.

Testing the Independent and Joint Contribution of Exposure to Neurodevelopmental Adversity and Childhood Trauma to Risk of Psychotic Experiences in Adulthood

Exposure to neurodevelopmental adversity and childhood trauma are both independently associated with psychosis. However, there is little research on the mechanism underlying their relationship with each other. The current study investigated both the independent and joint effects of neurodevelopmental adversity and childhood trauma to better understand the etiology of psychosis. A large population-based cohort (N = 3514) followed from birth was assessed on psychotic experiences (PE) at 24 years. Neurodevelopmental adversity included obstetric complications (birth weight, gestational age, in-utero influenza exposure, resuscitation) and developmental impairment (cognitive and motor impairments). Trauma exposure included caregiver and peer inflicted trauma up to 17 years. Multiple regression models tested their independent and interactive effect on PE, and path analysis estimated the indirect effect of neurodevelopmental adversity on PE via trauma. Neurodevelopmental adversity (OR = 1.32, 95%CI: 1.08-1.62) and trauma (OR = 1.97, 95%CI: 1.65-2.36) independently increased the odds of PE. There was also an indirect relationship between neurodevelopmental adversity and PE via increased exposure to childhood trauma (β = 0.01, 95%CI: 0.004-0.024). In particular, peer bullying mediated the association between developmental impairment to PE (β = 0.02, 95%CI: 0.01-0.03). In conclusion, children with neurodevelopmental adversity, in particular those with developmental impairment, are more likely to be exposed to trauma. This new etiological understanding of psychosis suggests that PE may be partially modifiable through reducing exposure to peer bullying, especially in children with developmental impairment.

A novel CERNNE approach for predicting Parkinson's Disease-associated genes and brain regions based on multimodal imaging genetics data

The detection and pathogenic factors analysis of Parkinson's disease (PD) has a practical significance for its diagnosis and treatment. However, the traditional research paradigms are commonly based on single neural imaging data, which is easy to ignore the complementarity between multimodal imaging genetics data. The existing researches also pay little attention to the comprehensive framework of patient detection and pathogenic factors analysis for PD. Based on functional magnetic resonance imaging (fMRI) data and single nucleotide polymorphism (SNP) data, a novel brain disease multimodal data analysis model is proposed in this paper. Firstly, according to the complementarity between the two types of data, the classical correlation analysis method is used to construct the fusion feature of subjects. Secondly, based on the artificial neural network, the fusion feature analysis tool named clustering evolutionary random neural network ensemble (CERNNE) is designed. This method integrates multiple neural networks constructed randomly, and uses clustering evolution strategy to optimize the ensemble learner by adaptive selective integration, selecting the discriminative features for PD analysis and ensuring the generalization performance of the ensemble model. By combining with data fusion scheme, the CERNNE is applied to forming a multi-task analysis framework, recognizing PD patients and predicting PD-associated brain regions and genes. In the multimodal data experiment, the proposed framework shows better classification performance and pathogenic factors predicting ability, which provides a new perspective for the diagnosis of PD.

Polygenic risk for schizophrenia and subcortical brain anatomy in the UK Biobank cohort

Research has shown differences in subcortical brain volumes between participants with schizophrenia and healthy controls. However, none of these differences have been found to associate with schizophrenia polygenic risk. Here, in a large sample (n = 14,701) of unaffected participants from the UK Biobank, we test whether schizophrenia polygenic risk scores (PRS) limited to specific gene-sets predict subcortical brain volumes. We compare associations with schizophrenia PRS at the whole genome level ('genomic', including all SNPs associated with the disorder at a p-value threshold < 0.05) with 'genic' PRS (based on SNPs in the vicinity of known genes), 'intergenic' PRS (based on the remaining SNPs), and genic PRS limited to SNPs within 7 gene-sets previously found to be enriched for genetic association with schizophrenia ('abnormal behaviour,' 'abnormal long-term potentiation,' 'abnormal nervous system electrophysiology,' 'FMRP targets,' '5HT2C channels,' 'CaV2 channels' and 'loss-of-function intolerant genes'). We observe a negative association between the 'abnormal behaviour' gene-set PRS and volume of the right thalamus that survived correction for multiple testing (ß = -0.031, pFDR = 0.005) and was robust to different schizophrenia PRS p-value thresholds. In contrast, the only association with genomic PRS surviving correction for multiple testing was for right pallidum, which was observed using a schizophrenia PRS p-value threshold < 0.01 (ß = -0.032, p = 0.0003, pFDR = 0.02), but not when using other PRS P-value thresholds. We conclude that schizophrenia PRS limited to functional gene sets may provide a better means of capturing differences in subcortical brain volume than whole genome PRS approaches.