Intellectual disability and other neuropsychiatric outcomes in high-risk children of mothers with schizophrenia, bipolar disorder and unipolar major depression

Risk of Neurodevelopmental Disorders in Offspring of Parents with Major Depressive Disorder: A Birth Cohort Study

Studies have reported inconsistent results regarding associations between parental depression and offspring neurodevelopmental disorders, such as developmental delay and autism spectrum disorder (ASD). In all, 7,593 children who were born between 1996 and 2010 in Taiwan and had at least one parent with major depressive disorder and 75,930 birth-year- and sex-matched children of parents without major depressive disorder were followed from 1996 or time of birth to the end of 2011. Intergroup differences in neurodevelopmental conditions-including ASD, attention-deficit hyperactivity disorder (ADHD), tic disorder, developmental delay, and intellectual disability (ID)-were assessed. Compared with the children in the control group, the children of parents with major depression were more likely [hazard ratio (HR), 95% confidence interval (CI)] to develop ADHD (1.98, 1.80-2.18), ASD (1.52, 1.16-1.94), tic disorder (1.40, 1.08-1.81), developmental delay (1.32, 1.20-1.45), and ID (1.26, 1.02-1.55). Parental depression was associated with offspring neurodevelopmental disorders, specifically ASD, ADHD, developmental delay, ID, and tic disorder. Therefore, clinicians should closely monitor the neurodevelopmental conditions of children of parents with depression.

Adverse Childhood Experiences and Autism: A Meta-Analysis

Evidence suggests that autistic children have a higher probability of experiencing adverse childhood experiences (ACEs) compared to their non-autistic peers. This meta-analysis (PROSPERO: CRD42022262635) aimed to quantify the association of autism and ACEs. Eight databases and Google Scholar were searched for studies that reported dichotomous outcomes regarding the associations between ACEs and autistic individuals, compared to non-autistic individuals. A random-effects model was used to calculate the average Odds Ratio (OR) of the relationship between a diagnosis of autism and ACEs. A total of 40 studies with 5,619,584 participants were included, generating an overall average OR 2.11 (CI 1.61, 2.77). Significant differences in the magnitude of association were found across studies with regards to the type of ACEs studied, comparison groups, and population type. Overall, moderate certainty evidence (downgraded for bias) indicates that autistic individuals are at greater risk of experiencing ACEs, compared to non-autistic individuals. Appropriate support for autistic individuals and their families are required to prevent ACEs and treat the impact of ACEs.

Effects of bipolar disorder on maternal and fetal health during pregnancy: a systematic review

BACKGROUND

Bipolar disorder (BD) is a mental disorder characterized by mood shifts from severe depression to mania. Pregnant women with BD may experience manic or depressive episodes, so they are usually concerned about the effects of BD on their pregnancy. The aim of this systematic review is to determine the effects of BD on maternal health and fetal health, weight, and development. It also addresses how BD affects the probability of incidence of pregnancy complications in women with bipolar compared with healthy controls.

METHODS

Seven electronic databases (Ovid MEDLINE, Embase, MIDRIS, APA PsychINFO, Scopus, Web of Science, and ScienceOpen) were searched, and 1728 eligible studies were identified. After deduplication, screening, and manual search processes, we included only 15 studies. Descriptive analysis, and calculation of the probability of incidence for each pregnancy outcome were used to analyze the results.

RESULTS

The findings of the included studies suggest that BD during pregnancy may affect both fetal growth and maternal health by increasing the risk of giving birth to an infant with some birth defects such as microcephaly, CNS problems, small for gestational age, and other congenital anomalies, in addition to causing some obstetric complications such as gestational hypertension, preterm labor, need for assisted delivery, hospital readmission, and others.

CONCLUSION

Bipolar disorder during pregnancy negatively affects mothers and their fetuses and increases the probability of incidence of obstetrics complications.

Mental and pediatric disorders among children 0-6 years of parents with severe mental illness

OBJECTIVE

Parental severe mental illness (SMI) increases the lifetime risk of mental and pediatric disorders in the offspring but little is known about specific disorders during early childhood. The primary aim was to investigate the incidence of mental and pediatric disorders among children 0-6 years old exposed to parental SMI, and secondarily to investigate the distribution of disorders on specific child age.

METHODS

A nationwide, register-based cohort study of 1,477,185 children born in Denmark between 1994.01.01 and 2016.12.31. Incidence rate ratios were calculated using Poisson regression analysis for any and specific mental and pediatric disorders.

RESULTS

IRR for any psychiatric disorder was elevated by a factor 2-5 among SMI offspring. Maternal schizophrenia resulted in the highest IRR = 5.23 (4.80-5.69) of any child psychiatric disorder. The risk of anxiety/OCD and attachment disorder among offspring exposed to parental, and in particular maternal, SMI was markedly raised with IRRs for anxiety/OCD between 7.59 and 17.02 and attachment disorders between 6.26 and 15.40. IRRs of mental disorders were highest at age 0-1 year and declined with age. IRR for any pediatric disorder was also elevated with IRRs between 1.01 and 1.28. Disorders of the digestive system and ill-defined symptoms were associated with the highest IRRs. Maternal (vs. paternal) SMI was associated with higher IRRs. IRRs declined slightly with child age.

CONCLUSION

Children exposed to parental SMI are at increased risk of mental and pediatric disorders during early childhood, particularly anxiety/OCD and attachment disorders. If associations are estimates of a modifiable causal relationship, our results indicate a need for early intervention to promote mental and pediatric health among SMI offspring.

A systematic review of the biological, social, and environmental determinants of intellectual disability in children and adolescents

AIM

This systematic review aimed to identify the most important social, environmental, biological, and/or genetic risk factors for intellectual disability (ID).

METHODS

Eligible were published prospective or retrospective comparative studies investigating risk factors for ID in children 4-18 years. Exclusions were single group studies with no comparator without ID and a sample size <100. Electronic databases (Medline, Cochrane Library, EMBASE, PsycInfo, Campbell Collaboration, and CINAHL) were searched for eligible publications from 1980 to 2020. Joanna Briggs Institute critical appraisal instruments, appropriate for study type, were used to assess study quality and risk of bias. Descriptive characteristics and individual study results were presented followed by the synthesis for individual risk factors, also assessed using GRADE.

RESULTS

Fifty-eight individual eligible studies were grouped into six exposure topics: sociodemographic; antenatal and perinatal; maternal physical health; maternal mental health; environmental; genetic or biological studies. There were few eligible genetic studies. For half the topics, the certainty of evidence (GRADE) was moderate or high.

CONCLUSION

Multiple studies have examined individual potential determinants of ID, but few have investigated holistically to identify those populations most at risk. Our review would indicate that there are vulnerable groups where risk factors we identified, such as low socioeconomic status, minority ethnicity, teenage motherhood, maternal mental illness, and alcohol abuse, may cluster, highlighting a target for preventive strategies. At-risk populations need to be identified and monitored so that interventions can be implemented when appropriate, at preconception, during pregnancy, or after birth. This could reduce the likelihood of ID and provide optimal opportunities for vulnerable infants.

SYSTEMATIC REVIEW REGISTRATION

[https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=120032], identifier [CRD42019120032].

Molecular characterisation of rare loss-of-function NPAS3 and NPAS4 variants identified in individuals with neurodevelopmental disorders

Aberrations in the excitatory/inhibitory balance within the brain have been associated with both intellectual disability (ID) and schizophrenia (SZ). The bHLH-PAS transcription factors NPAS3 and NPAS4 have been implicated in controlling the excitatory/inhibitory balance, and targeted disruption of either gene in mice results in a phenotype resembling ID and SZ. However, there are few human variants in NPAS3 and none in NPAS4 that have been associated with schizophrenia or neurodevelopmental disorders. From a clinical exome sequencing database we identified three NPAS3 variants and four NPAS4 variants that could potentially disrupt protein function in individuals with either developmental delay or ID. The transcriptional activity of the variants when partnered with either ARNT or ARNT2 was assessed by reporter gene activity and it was found that variants which truncated the NPAS3/4 protein resulted in a complete loss of transcriptional activity. The ability of loss-of-function variants to heterodimerise with neuronally enriched partner protein ARNT2 was then determined by co-immunoprecipitation experiments. It was determined that the mechanism for the observed loss of function was the inability of the truncated NPAS3/4 protein to heterodimerise with ARNT2. This further establishes NPAS3 and NPAS4 as candidate neurodevelopmental disorder genes.

Bipolar Disorder and Psychosis in Autism

Autism seldom occurs in its pure form. Often labeled as behavioral disorders or psychological reactions, comorbid psychiatric disorders are common. Bipolar disorder is one of the most common psychiatric disorders that occur in persons with autism across their life spans. It can be comorbid with and mistaken for several other conditions. Similarly, psychosis occurs in several psychiatric disorders. Schizophrenia is the prototype psychotic disorder that has a close but controversial relationship with autism. Assessment and treatment of bipolar disorder and psychosis should be based on their individual characteristics, family dynamics, and community resources.

Bipolar Disorder and Psychosis in Autism

Autism seldom occurs in its pure form. Often labeled as behavioral disorders or psychological reactions, comorbid psychiatric disorders are common. Bipolar disorder is one of the most common psychiatric disorders that occur in persons with autism across their life spans. It can be comorbid with and mistaken for several other conditions. Similarly, psychosis occurs in several psychiatric disorders. Schizophrenia is the prototype psychotic disorder that has a close but controversial relationship with autism. Assessment and treatment of bipolar disorder and psychosis should be based on their individual characteristics, family dynamics, and community resources.

Parsing components of risk of premature mortality in the children of mothers with severe mental illness

INTRODUCTION

Children of mothers with severe mental illness are at increased risk of premature death including in infancy and early childhood. Importantly, these children are also more likely to be exposed to adverse socio-demographic risk factors and serious obstetric complications which, of themselves, may increase risk for childhood mortality. We examined mortality outcome at different ages up to 5 years taking account of these risks.

METHOD

We used linked data across Western Australian whole-population psychiatric, inpatient, death, and midwives' registers to identify 15,486 births to mothers with severe mental illness and 452,459 births to mothers with no mental illness. Multivariable models were adjusted for exposure to adverse socio-demographic risk factors and serious obstetric complications.

RESULTS

Overall risk of premature death was increased amongst children of mothers with severe mental illness (2.3%, 354 deaths) compared with children of mothers with no mental illness (1.4%, 6523 deaths); the same was true for specific risk of stillbirth, neonatal, post‑neonatal and early childhood deaths. Risk was substantially attenuated after adjustment for adverse socio-demographic exposures, and further still after adjustment for exposure to serious obstetric complications. We observed no effects for the timing of maternal illness diagnosis.

CONCLUSIONS

To minimise the risk of premature mortality in the children of mothers with severe mental illness, priority should be given to the prompt diagnosis of maternal mental illness with targeted delivery of high quality antenatal and psychiatric care, as well as social and structural supports for affected families that continue after birth.

Morbidity and Mortality in the Children and Young Adult Offspring of Parents With Schizophrenia or Affective Disorders-A Nationwide Register-Based Cohort Study in 2 Million Individuals

BACKGROUND

The offspring of parents with severe mental illness (SMI) are at higher risk of mortality and of developing certain somatic diseases. However, across the full spectrum of somatic illness, there remains a gap in knowledge regarding morbidity.

METHODS

We conducted a register-based nationwide cohort study of all 2 000 694 individuals born in Denmark between 1982 and 2012. Maximum age of offspring at follow-up was 30 years. Information on parents' psychiatric diagnoses of schizophrenia, bipolar disorder, and unipolar depression was retrieved from the Psychiatric Central Register. We estimated incidence rate ratio (IRR), cumulative incidence percentage and mortality rate ratio of first hospital contact for a broad spectrum of somatic illnesses according to the International Statistical Classification of Diseases and Related Health Problems. Analyses were adjusted for important confounders.

RESULTS

Offspring of individuals with SMI had higher risk of somatic hospital contacts IRR: 1.17 (95% CI: 1.16-1.18) with maternal depression being associated with the highest IRR (1.22, 95% CI: 1.20-1.24). Offspring of parents with SMI had higher risk within most broad diagnostic categories with highest IRRs for unclassified somatic diagnoses, infections and endocrine diseases ranging from 1.27 (95% CI: 1.25-1.28) to 1.26 (95% CI: 1.23-1.29) (all P < .0001). Morbidity was particularly increased in children aged 0-7 years. The mortality rate ratio associated with parental SMI was 1.31 (95% CI: 1.21-1.41) with excess mortality mainly due to unnatural causes.

CONCLUSION

Our findings indicate that offspring of parents with SMI experienced increased mortality and somatic morbidity warranting heightened vigilance and support for this population.

Burden of major depressive disorder and quality of life among mothers of children with autism spectrum disorder in urban bangladesh

This cross-sectional study examined the burden of depression and quality of life (QoL) among mothers of children with autism spectrum disorder (ASD) attending six schools offering special educational services for children with ASD in urban Dhaka, Bangladesh. All consenting mothers were 18 years of age and older and met criteria for major depressive disorder (MDD) on the Structured Interview for DSM-V-TR Research Version-non patient edition administered by trained raters. QoL was assessed by the EuroQol five-dimensional standardized questionnaire. MDD was diagnosed in 45% of mothers and was proportionally higher among those who did not work outside the home, had no childcare support at home, expressed low level of satisfaction with the quality of providers when they had sought care for their children with ASD, and reported being recipient of negative attitudes from neighbors toward their children with ASD. QoL was negatively associated with MDD, mothers' illness, and low satisfaction with the health care providers for children with ASD, as well as experiencing a negative attitude by neighbors toward their children. QoL was positively associated with the reported family monthly income and improvement of the children with ASD on school attendance. The prevalence of MDD among mothers of children with ASD was high and associated with poor QoL. Integrating mental health services and supports for mothers in the ASD care of children is likely to address the high burden of depression they face, and improve their overall quality of life. Autism Res 2020, 13: 284-297. © 2019 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: The levels of depression were assessed among mothers of children with autism spectrum disorder (ASD) attending six schools offering special educational services for children with ASD in urban Dhaka, Bangladesh. Almost one in two mothers was found to have major depression. The quality of life of these mothers was generally poor. Integrating mental health services for mothers with ASD care in children is likely to address the burden of depression among the mothers of children with ASD and improve overall quality of life.

Schizophrenia and motherhood

The primary aim of this study was to analyze the impact of schizophrenic disorders on pregnancy outcomes. The secondary aim was to briefly analyze the potential role of antipsychotic treatment on influencing pregnancy outcomes in expectant mothers with schizophrenia. We searched the MEDLINE, PsycINFO, and Science.gov databases for articles published in English from January 1980 to January 2019. We used the following search terms: 'schizophrenia', 'motherhood', 'pregnancy/foetal/neonatal outcomes', and 'birth defects'. The reference lists of retrieved articles were also consulted to find additional pertinent studies missed in the electronic search and/or those published before 1980. Data were extracted from articles that provided primary data on the impact of maternal schizophrenia spectrum disorders on obstetrical and perinatal outcomes. After excluding duplicates, 35 articles were identified. Systematic reviews were searched on the same databases to briefly assess the effects of antipsychotics on pregnancy outcomes. The reviewed studies showed several limitations. They were published during a time range from the early 1970s to 2019. During this period, there were significant changes in the diagnostic criteria for schizophrenia. Moreover, such studies showed no homogeneity in the investigation of potential confounders. Most importantly, no research has differentiated the effects of maternal illness on pregnancy, fetal, and neonatal outcomes from those associated with antipsychotic treatments. Thus, it is not surprising that such studies show conflicting results. Despite such limitations, in managing pregnant women with schizophrenia clinicians should consider an integrated approach that includes: antipsychotic treatment, psychological treatment, optimal dietary approaches for prevention of excessive weight gain and gestational diabetes, meticulous gynecologic and obstetric surveillance, and social and occupational support.

Intellectual disability and mental disorders in a US population representative sample of adolescents

BACKGROUND

Most research on the prevalence, distribution, and psychiatric comorbidity of intellectual disability (ID) relies on clinical samples, limiting the generalizability and utility of ID assessment in a legal context. This study assessed ID prevalence in a population-representative sample of US adolescents and examined associations of ID with socio-demographic factors and mental disorders.

METHODS

Data were drawn from the National Comorbidity Survey Adolescent Supplement (N = 6256). ID was defined as: (1) IQ ⩽ 76, measured using the Kaufman Brief Intelligence Test; (2) an adaptive behavior score ⩽76, and (3) age of onset ⩽18 measured using a validated scale. The Composite International Diagnostic Interview assessed 15 lifetime mental disorders. The Sheehan disability scale assessed disorder severity. We used logistic regression models to estimate differences in lifetime disorders for adolescents with and without ID.

RESULTS

ID prevalence was 3.2%. Among adolescents with ID, 65.1% met lifetime criteria for a mental disorder. ID status was associated with specific phobia, agoraphobia, and bipolar disorder, but not behavior disorders after adjustment for socio-demographics. Adolescents with ID and mental disorders were significantly more likely to exhibit severe impairment than those without ID.

CONCLUSIONS

These findings highlight how sample selection and overlap between ID and psychopathology symptoms might bias understanding of the mental health consequences of ID. For example, associations between ID and behavior disorders widely reported in clinical samples were not observed in a population-representative sample after adjustment for socio-demographic confounders. Valid assessment and understanding of these constructs may prove influential in the legal system by influencing treatment referrals and capital punishment decisions.General Scientific SummaryCurrent definitions of intellectual disability (ID) are based on three criteria: formal designation of low intelligence through artificial problem-solving tasks, impairment in one's ability to function in his/her social environment, and early age of onset. In a national population sample of adolescents, the majority of those with ID met criteria for a lifetime mental disorder. Phobias and bipolar disorder, but not behavior disorders, were elevated in adolescents with ID. Findings highlight the need to consider how behavioral problems are conceptualized and classified in people with ID.

Developmental outcomes at age four following maternal antiepileptic drug use

We investigated whether prenatal antiepileptic drug (AED) exposure was associated with adverse outcomes in the Before School Check (B4SC) assessments, particularly the assessments measuring neurodevelopment. Children exposed to AEDs were identified by linking women dispensed AEDs in the Pharmaceutical Collection to births recorded on the National Minimum Dataset (NMDS). Multinomial logistic regression was used to estimate adjusted risk ratios (aRRs) and 95% confidence intervals (CIs) for outcomes of the parent-completed Parental Evaluation of Developmental Status (PEDS) questionnaire and Strengths and Difficulties Questionnaire (SDQ), after adjusting for gender, ethnicity, and socioeconomic deprivation. Between 2012 and 2016, 606 children with a mother who had been dispensed one or more AEDs during pregnancy had taken part in the B4SC. Prenatal exposure to sodium valproate (n = 161) or lamotrigine (n = 149) monotherapy was associated with an increased risk of having an abnormal SDQ - parent-completed (SDQP) score, ≥17 - indicating emotional or behavioral concerns (9.32% of children exposed to sodium valproate monotherapy had an abnormal score; aRR: 2.11; 1.23-3.63; lamotrigine 8.05%; aRR: 2.21; 1.21-4.02). Prenatal exposure to carbamazepine monotherapy (n = 201) was not associated with an increased risk of having an abnormal total SDQP score but was associated with increased risks in the individual domains of the SDQP. Prenatal exposure to AED polytherapy (n = 57) was associated with the highest risk of abnormal SDQP scores (17.54% of children exposed to polytherapy had abnormal scores; aRR: 2.75; 1.25-6.02). Prenatal exposure to sodium valproate and lamotrigine is associated with an increased risk of concerns about emotional and behavioral development being reported by parents in a neurodevelopmental screening program. Additional investigation is required into why significant differences between AEDs were not seen in this study.

Risk of neurological, eye and ear disease in offspring to parents with schizophrenia or depression compared with offspring to healthy parents

BACKGROUND

Neurological, visual and hearing deviations have been observed in the offspring of parents with schizophrenia. This study test whether children to parents hospitalized with schizophrenia have increased the likelihood of childhood neurological disorder.

METHODS

Among all parents in Sweden born 1950-1985 and with offspring born 1968-2002: 7107 children with a parent hospitalized for schizophrenia were compared to 172 982 children with no parents hospitalized for schizophrenia or major depression, as well as to 32 494 children with a parent hospitalized for major depression as a control population with another severe psychiatric outcome. We estimated relative risks (RR) and two-sided 95% confidence intervals calculated from Poisson regression.

RESULTS

Children to parents with schizophrenia were more likely than controls to have been hospitalized before the age of 10 with a diagnosis of cerebral palsy, RR = 1.76 (95% CI: 1.15-2.69); epilepsy, RR = 1.78 (95% CI: 1.33-2.40), combined neurological disease, RR = 1.33 (95% CI: 1.11-1.60) and certain diseases of the eye, RR = 1.92 (95% CI: 1.17-3.15) and ear, RR = 1.18 (95% CI: 1.05-1.32). Similar disease-risk-pattern was found for children to parents hospitalized with a diagnosis of major depression. A specific risk increase for strabismus RR = 1.21 (95%CI: 1.05-1.40) was found for off-spring with parental depression.

CONCLUSIONS

Compared with children to healthy parents, children to parents with schizophrenia have increased risk of a variety of neurological disorders as well as visual and hearing disorders at an early age. The risk increase was not specific to schizophrenia but was also seen in children to parents with a diagnosis of major depression.

Cross-Disorder Cognitive Impairments in Youth Referred for Neuropsychiatric Evaluation

OBJECTIVES

Studies suggest that impairments in some of the same domains of cognition occur in different neuropsychiatric conditions, including those known to share genetic liability. Yet, direct, multi-disorder cognitive comparisons are limited, and it remains unclear whether overlapping deficits are due to comorbidity. We aimed to extend the literature by examining cognition across different neuropsychiatric conditions and addressing comorbidity.

METHODS

Subjects were 486 youth consecutively referred for neuropsychiatric evaluation and enrolled in the Longitudinal Study of Genetic Influences on Cognition. First, we assessed general ability, reaction time variability (RTV), and aspects of executive functions (EFs) in youth with non-comorbid forms of attention-deficit/hyperactivity disorder (ADHD), mood disorders and autism spectrum disorder (ASD), as well as in youth with psychosis. Second, we determined the impact of comorbid ADHD on cognition in youth with ASD and mood disorders.

RESULTS

For EFs (working memory, inhibition, and shifting/ flexibility), we observed weaknesses in all diagnostic groups when participants' own ability was the referent. Decrements were subtle in relation to published normative data. For RTV, weaknesses emerged in youth with ADHD and mood disorders, but trend-level results could not rule out decrements in other conditions. Comorbidity with ADHD did not impact the pattern of weaknesses for youth with ASD or mood disorders but increased the magnitude of the decrement in those with mood disorders.

CONCLUSIONS

Youth with ADHD, mood disorders, ASD, and psychosis show EF weaknesses that are not due to comorbidity. Whether such cognitive difficulties reflect genetic liability shared among these conditions requires further study. (JINS, 2018, 24, 91-103).

Gestational age at birth and risk of intellectual disability without a common genetic cause

Preterm birth is linked to intellectual disability and there is evidence to suggest post-term birth may also incur risk. However, these associations have not yet been investigated in the absence of common genetic causes of intellectual disability, where risk associated with late delivery may be preventable. We therefore aimed to examine risk of intellectual disability without a common genetic cause across the entire range of gestation, using a matched-sibling design to account for unmeasured confounding by shared familial factors. We conducted a population-based retrospective study using data from the Stockholm Youth Cohort (n = 499,621) and examined associations in a nested cohort of matched outcome-discordant siblings (n = 8034). Risk of intellectual disability was greatest among those born extremely early (adjusted OR_{24 weeks} = 14.54 [95% CI 11.46-18.44]), lessening with advancing gestational age toward term (aOR_{32 weeks} = 3.59 [3.22-4.01]; aOR_37weeks = 1.50 [1.38-1.63]); aOR_{38 weeks} = 1.26 [1.16-1.37]; aOR₃₉ weeks = 1.10 [1.04-1.17]) and increasing with advancing gestational age post-term (aOR_{42 weeks} = 1.16 [1.08-1.25]; aOR_{43 weeks} = 1.41 [1.21-1.64]; aOR_{44 weeks} = 1.71 [1.34-2.18]; aOR_{45 weeks} = 2.07 [1.47-2.92]). Associations persisted in a cohort of matched siblings suggesting they were robust against confounding by shared familial traits. Risk of intellectual disability was greatest among children showing evidence of fetal growth restriction, especially when birth occurred before or after term. Birth at non-optimal gestational duration may be linked causally with greater risk of intellectual disability. The mechanisms underlying these associations need to be elucidated as they are relevant to clinical practice concerning elective delivery around term and mitigation of risk in post-term children.

Associations between Familial Rates of Psychiatric Disorders and De Novo Genetic Mutations in Autism

The purpose of this study was to examine the confluence of genetic and familial risk factors in children with Autism Spectrum Disorder (ASD) with distinct de novo genetic events. We hypothesized that gene-disrupting mutations would be associated with reduced rates of familial psychiatric disorders relative to structural mutations. Participants included families of children with ASD in four groups: de novo duplication copy number variations (DUP, n = 62), de novo deletion copy number variations (DEL, n = 74), de novo likely gene-disrupting mutations (LGDM, n = 267), and children without a known genetic etiology (NON, n = 2111). Familial rates of psychiatric disorders were calculated from semistructured interviews. Results indicated overall increased rates of psychiatric disorders in DUP families compared to DEL and LGDM families, specific to paternal psychiatric histories, and particularly evident for depressive disorders. Higher rates of depressive disorders in maternal psychiatric histories were observed overall compared to paternal histories and higher rates of anxiety disorders were observed in paternal histories for LGDM families compared to DUP families. These findings support the notion of an additive contribution of genetic etiology and familial factors are associated with ASD risk and highlight critical need for continued work targeting these relationships.

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

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

Barbara Fish and a Short History of the Neurodevelopmental Hypothesis of Schizophrenia

The neurodevelopmental hypothesis of schizophrenia has become a paradigm broadly accepted in today's research in schizophrenia and its spectrum. This article traces the historical development of the neurodevelopmental hypothesis of schizophrenia up until the time of its explicit formulation in 1987, by Weinberger and by Murray and Lewis, with a main focus on the seminal contribution of Barbara Fish to its conception and elaboration.

Neurodevelopmental outcomes in infants exposed in utero to antipsychotics: a systematic review of published data

The proportion of pregnancies exposed to either second-generation antipsychotics (SGAs) or first-generation antipsychotics (FGAs) varies between 0.3%-2% of all pregnancies, but, until now, little is known about the potential neurobehavioral teratogenicity of antipsychotics. Assessing this safety facet is the aim of this article. PubMed, Scopus, and Google Scholar were searched for eligible articles. PubMed (1954 to May 2016) was searched using several medical subject headings, variously combined. PubMed search results were also limited using the search filter for human studies published in English. Scopus and Google Scholar searches were filtered for article title (antipsychotics/neuroleptics, pregnancy). After excluding duplicates, 9,250 articles were identified and 29 met the following inclusion criteria: only articles that provided original/primary data on neurodevelopmental outcome in human offspring older than 4 months of age, independently of the study design, were selected for review. Indeed, some relevant neurodevelopmental milestones are achieved at this time. Length of study and neurodevelopmental assessment methodology did not influence the study selection. Unfortunately, published data on neurodevelopmental teratogenicity of SGAs mainly derive from case reports and small case-series studies. Even findings emerging from case-control and prospective/retrospective studies are of limited clinical relevance because of their small sample sizes. Limited data are also available on FGAs. Hence, we have to conclude that the long-term neurodevelopmental outcomes for children exposed in utero remain unclear. Low to very low quality evidence of retrieved data makes impossible to confirm or exclude potential long-lasting untoward effects on infant neurocognitive development associate with antenatal exposure to either SGAs or FGAs.

Differences in cognitive impairment between schizophrenia and bipolar disorder: Considering the role of heterogeneity

Schizophrenia is associated with significant cognitive impairment. Bipolar disorder (BD) also presents with cognitive deficits that are similar to, albeit less severe, than those reported in schizophrenia. There has been controversy over whether selective deficits in social cognition or developmental trajectory of cognitive deficits can distinguish schizophrenia from BD. Also, available studies have not generally considered the potential effect of cognitive heterogeneity within the two disorders on between-group differences. The current review examines the evidence on the specificity of social cognitive deficits and early neurocognitive impairment to schizophrenia and explores the overall outcome of studies investigating within and cross-diagnosis cognitive heterogeneity in schizophrenia and BD. Current evidence does not support the specificity of social cognitive impairment to schizophrenia. Available studies also suggest that cognitive impairment in premorbid and early stages is evident not only in schizophrenia but also in many BD patients. Both schizophrenia and BD have a number of cognitive subgroups, including severe impairment, good functioning, and one or more selective or modest impairment clusters. While both disorders are represented in each cognitive subgroup, there are significant cross-diagnostic differences regarding prevalences of individuals belonging to the severe impairment and good functioning subgroups. Individuals with schizophrenia are much more likely to exhibit severe cognitive impairment than individuals with BD and good cognitive functioning is more often observed in BD patients than schizophrenia patients. Further identification of the neurobiological and genetic characteristics of the cognitive subgroups in major psychoses can improve the validity of diagnostic systems and can advance the development of personalized management approaches, including cognitive remediation.

Prenatal exposure to antidepressants and risk of epilepsy in childhood

PURPOSE

This study aimed to estimate the association between prenatal exposure to antidepressants and risk of epilepsy in childhood, taking maternal depression into account.

METHODS

We conducted a population-based cohort study including all Danish singletons born alive between 1997 and 2008 (n = 734 237). Information on antidepressant medication and diagnosis of depression and epilepsy was obtained from Danish National Registers. The exposed group comprised children of mothers who used antidepressants from 30 days before pregnancy until the date of birth. The reference group comprised children of mothers who used no antidepressants from 6 months before pregnancy to birth. We estimated the hazard ratios (HR) of epilepsy and 95% confidence intervals (CI) using Cox proportional hazard models.

RESULTS

We identified 12 438 (1.7%) children exposed to antidepressants during pregnancy (including 30 days before pregnancy) and 5829 (0.8%) children diagnosed with epilepsy in the follow-up time (mean: 6.7 years). Children exposed to antidepressants during pregnancy had a 27% higher risk of epilepsy (aHR: 1.27; 95%CI: 1.05-1.54) than children in the reference group. The estimate of this association was 1.71 (95%CI: 1.10-2.66) if their mothers also had a registry-based hospital diagnosis of depression in the 6 months before pregnancy or during pregnancy and 1.14 (95%CI: 0.91-1.43) if their mothers had no registry-based hospital diagnosis of depression. Children of mothers who used antidepressants from 2 to 6 months before pregnancy (but not during pregnancy) had an increased risk of epilepsy (aHR: 1.36; 95%CI: 1.07-1.73).

CONCLUSIONS

Antidepressant use during pregnancy was associated with a higher risk of epilepsy among children whose mothers had also a registry-based hospital diagnosis of depression during pregnancy. Copyright © 2016 John Wiley & Sons, Ltd.

'Big data' in mental health research: current status and emerging possibilities

PURPOSE

'Big data' are accumulating in a multitude of domains and offer novel opportunities for research. The role of these resources in mental health investigations remains relatively unexplored, although a number of datasets are in use and supporting a range of projects. We sought to review big data resources and their use in mental health research to characterise applications to date and consider directions for innovation in future.

METHODS

A narrative review.

RESULTS

Clear disparities were evident in geographic regions covered and in the disorders and interventions receiving most attention.

DISCUSSION

We discuss the strengths and weaknesses of the use of different types of data and the challenges of big data in general. Current research output from big data is still predominantly determined by the information and resources available and there is a need to reverse the situation so that big data platforms are more driven by the needs of clinical services and service users.

Preventing intellectual disability during pregnancy: what are the potentially high yield targets?

OBJECTIVE

To identify risk factors among children with unknown cause intellectual disability (ID) and to estimate the population-attributable risk (PAR) associated with these factors.

METHODS

This was a retrospective cohort study of maternal and child pairs born between 2004 and 2010 in South Carolina, and information was obtained from Medicaid billing records, birth certificates, and other administrative data. The data included 123,922 children and logistic generalized estimating equations (GEE) regression models were used to estimate the association of maternal risk factors and ID. We estimated models with and without birth weight as a covariate, since low birth weight is known to be a mediator of the association between some risk factors and ID in children.

RESULTS

The prevalence of ID in the children was 3.85% and the associations between risk factors and ID were similar for female and male children. We found that the odds of having ID were increased if a child's mother had a diagnosis of major depression; for male children, the odds ratio (OR) was 1.34 (95% confidence interval [CI] 1.14-1.59, PAR 2.17%); and for females, the OR was 1.59 (95% CI 1.30-1.95, PAR 4.70%). The odds of having ID were also increased for children of women with bipolar disorder (males - OR 1.95, 95% CI 1.53-2.48, PAR 2.85%; females - OR 1.63, 95% CI 1.20-2.22, PAR 2.05%).

CONCLUSIONS

Major maternal depression and bipolar disorder were each significantly associated with the odds of ID in children, each accounting for approximately 2-5% of the PAR, when controlling for covariates.

Pregnancy in Women With Intellectual and Developmental Disabilities

OBJECTIVE

Our objectives were to describe the general fertility rate (GFR) and age-specific fertility rates (ASFRs) of women with intellectual and developmental disabilities (IDD) and the social and health characteristics of those with a singleton live birth, and to compare these to women without IDD.

METHODS

In this population-based retrospective cohort study using linked Ontario health and social services administrative data, we identified 18- to 49-year-old women with IDD (N = 21 181) and without IDD (N = 990 776). The GFR and ASFRs (2009) were calculated for both groups and compared using rate ratios (RR) and 95% confidence intervals (CI). Among women with a singleton live birth (N = 423 with, N = 42 439 without IDD), social and health characteristics were compared using Pearson's Chi square tests.

RESULTS

The GFR in women with IDD (20.3 per 1000) was lower than that in women without IDD (43.4 per 1000) (RR 0.47; 95% CI 0.43 to 0.51). ASFRs in 18- to 24-year-olds were similar in both groups. Among women with a singleton live birth, those with IDD were younger and had higher rates of poverty, epilepsy, obesity, and mental health issues. They also had high rates of medication use during pregnancy.

CONCLUSION

In the largest study of fertility in women with IDD to date, we found that ASFRs are similar in young women with and without IDD. Women with IDD with a singleton live birth experience significant social and health disparities during pregnancy. These findings suggest the need to develop services to support the reproductive health of this vulnerable group.

Pregnancy risk factors in autism: a pilot study with artificial neural networks

BACKGROUND

Autism is a multifactorial condition in which a single risk factor can unlikely provide comprehensive explanation for the disease origin. Moreover, due to the complexity of risk factors interplay, traditional statistics is often unable to explain the core of the problem due to the strong inherent nonlinearity of relationships. The aim of this study was to assess the frequency of 27 potential risk factors related to pregnancy and peri-postnatal period.

METHODS

The mothers of 45 autistic children and of 68 typical developing children completed a careful interview. Twenty-four siblings of 19 autistic children formed an internal control group.

RESULTS

A higher prevalence of potential risk factors was observed in 22 and 15 factors in external control and internal control groups, respectively. For six of them, the difference in prevalence was statistically significant. Specialized artificial neural networks (ANNs) discriminated between autism and control subjects with 80.19% global accuracy when the dataset was preprocessed with TWIST (training with input selection and testing) system selecting 16 out of 27 variables. Logistic regression applied to 27 variables gave unsatisfactory results with global accuracy of 46%.

CONCLUSION

Pregnancy factors play an important role in autism development. ANNs are able to build up a predictive model, which could represent the basis for a diagnostic screening tool.

Breastfeeding and Postpartum Depression: An Overview and Methodological Recommendations for Future Research

Emerging research suggests that a relationship exists between breastfeeding and postpartum depression; however, the direction and precise nature of this relationship are not yet clear. The purpose of this paper is to provide an overview of the relationship between breastfeeding and postpartum depression as it has been examined in the empirical literature. Also, the potential mechanisms of action that have been implicated in this relationship are also explored. PubMed and PsycINFO were searched using the keywords: breastfeeding with postpartum depression, perinatal depression, postnatal depression. Results of this search showed that researchers have examined this relationship in diverse ways using diverse methodology. In particular, researchers have examined the relationships between postpartum depression and breastfeeding intention, initiation, duration, and dose. Due to a number of methodological differences among past studies we make some recommendations for future research that will better facilitate an integration of findings. Future research should (1) use standardized assessment protocols; (2) confirm diagnosis through established clinical interview when possible; (3) provide a clear operationalized definition for breastfeeding variables; (4) clearly define the postpartum period interval assessed and time frame for onset of symptoms; (5) be prospective or longitudinal in nature; and (6) take into consideration other potential risk factors identified in the empirical literature.

'You are Okay': a support and educational program for children with mild intellectual disability and their parents with a mental illness: study protocol of a quasi-experimental design

BACKGROUND

Children of parents with a mental illness or substance use disorder (COPMI) have an increased risk of developing social-emotional problems themselves. Fear of stigmatisation or unawareness of problems prevents children and parents from understanding each other. Little is known about COPMI with mild intellectual disabilities (ID), except that they have a high risk of developing social-emotional problems and require additional support. In this study, we introduce a program for this group, the effectiveness of which we will study using a quasi-experimental design based on matching. The program 'You are okay' consists of a support group for children and an online educational program for parents. The goal of the program is to increase children and parents' perceived competence with an aim to prevent social-emotional problems in children.

METHODS/DESIGN

Children between ten and twenty years old with mild ID (IQ between 50 and 85) and at least one of their parents with a mental illness will be included in the study. The children will receive part time treatment or residential care from an institute for children with mild ID and behavioural problems. Participants will be assigned to the intervention or the control group. The study has a quasi-experimental design. The children in the intervention group will join a support group, and their parents will be offered an online educational program. Children in the control group will receive care as usual, and their parents will have no extra offer. Assessments will be conducted at baseline, post-test, and follow up (6 months). Children, parents, and social workers will fill out the questionnaires.

DISCUSSION

The 'You are okay' program is expected to increase children and parents' perceived competence, which can prevent (further) social-emotional problem development. Because the mental illness of parents can be related to the behavioural problems of their children, it is important that children and parents understand each other. When talking about the mental illness of parents becomes standard in children's treatment, stigmatisation and the fear for stigmatisation can decrease.

TRIAL REGISTRATION

Dutch Trial Register NTR4845 . Registered 9 October 2014.

Parental and comorbid epilepsy in persons with bipolar disorder

BACKGROUND

Population-based studies have demonstrated an overrepresentation of bipolar disorder (BPD) in individuals with epilepsy. However, few studies have examined the reverse association, i.e. comorbid epilepsy in individuals selected based on BPD diagnosis. No previous population-based study having examined the co-occurrence of BPD and epilepsy has adjusted for parental psychopathology. Such an adjustment is motivated by population-based studies reporting an overrepresentation of various types of parental psychiatric disorders in both BPD and epilepsy. Furthermore, an association between epilepsy in first-degree relatives and BPD has previously only been examined and demonstrated in a small clinical sample. The objective of this study is to examine the associations between parental and comorbid epilepsy and BPD, adjusting for parental psychopathology.

METHODS

This nested case-control study identified 1861 cases with BPD, age up to 25 years, 3643 matched controls, and their parents from Finnish national registers. Conditional logistic regression was used to calculate odds ratios (ORs) with 95% confidence intervals (CIs) and two-sided significance limits of p<0.05.

RESULTS

BPD was associated with comorbid epilepsy (adjusted OR 2.53, 95% CI: 1.73-3.70) but not with parental epilepsy. Epilepsy was found in 3.33% of cases versus 1.29% of controls, 2.69% of cases' parents versus 2.53% of controls' parents.

LIMITATIONS

The diagnoses were register-based, not based on standardized procedures with direct ascertainment.

CONCLUSIONS

An association between BPD and comorbid epilepsy persists even after adjusting for parental psychopathology. Lack of familial clustering of BPD and epilepsy would suggest that the elevated co-occurrence of these disorders is influenced by non-genetic factors.

Incorporating Functional Information in Tests of Excess De Novo Mutational Load

A number of recent studies have investigated the role of de novo mutations in various neurodevelopmental and neuropsychiatric disorders. These studies attempt to implicate causal genes by looking for an excess load of de novo mutations within those genes. Current statistical methods for assessing this excess are based on the implicit assumption that all qualifying mutations in a gene contribute equally to disease. However, it is well established that different mutations can have radically different effects on the ultimate protein product and, as a result, on disease risk. Here, we propose a method, fitDNM, that incorporates functional information in a test of excess de novo mutational load. Specifically, we derive score statistics from a retrospective likelihood that incorporates the probability of a mutation being damaging to gene function. We show that, under the null, the resulting test statistic is distributed as a weighted sum of Poisson random variables and we implement a saddlepoint approximation of this distribution to obtain accurate p values. Using simulation, we have shown that our method outperforms current methods in terms of statistical power while maintaining validity. We have applied this approach to four de novo mutation datasets of neurodevelopmental and neuropsychiatric disorders: autism spectrum disorder, epileptic encephalopathy, schizophrenia, and severe intellectual disability. Our approach also implicates genes that have been implicated by existing methods. Furthermore, our approach provides strong statistical evidence supporting two potentially causal genes: SUV420H1 in autism spectrum disorder and TRIO in a combined analysis of the four neurodevelopmental and neuropsychiatric disorders investigated here.

Somatic diseases and conditions before the first diagnosis of schizophrenia: a nationwide population-based cohort study in more than 900 000 individuals

OBJECTIVE

Schizophrenia is associated with excess physical comorbidity. Yet, to our knowledge, large studies are lacking on the associations with somatic diseases before the onset of schizophrenia. The authors conducted a nationwide study of the full spectrum of treated somatic diseases before the first diagnosis of schizophrenia.

METHOD

Nationwide sample of the Danish population consisting of singletons (n = 954351) born 1977-1993 and followed from birth to 2009, during which period 4371 developed schizophrenia. Somatic diagnoses at all general hospital contacts (admitted or outpatient care at a somatic hospital) from 1977 to 2009 were used as exposures. The incidence rate ratio (IRR) of schizophrenia was calculated using Poisson regression adjusted for confounders.

RESULTS

Among the 4371 persons who developed schizophrenia from 1992 to 2009, a total of 4180 (95.6%) persons had a previous somatic hospital contact. A history of any somatic hospital contact was associated with an elevated risk of schizophrenia (IRR = 2.04, 95% CI = 1.77-2.37). A wide range of somatic diseases and conditions were associated with an increased risk of schizophrenia, including epilepsy (IRR = 2.26, 95% CI = 1.93-2.62), nutritional or metabolic disorders (IRR = 1.57, 95% CI = 1.39-1.77), circulatory system diseases (IRR = 1.63, 95% CI= 1.38-1.92), and brain injury (IRR = 1.58, 95% CI = 1.45-1.72).

CONCLUSIONS

A wide range of potential etiological factors could have contributed to the observed associations, including genetic or physiological overlaps between conditions, and interacting immunological, behavioral, and neurodevelopmental factors.

Developmental trajectory of cognitive impairment in bipolar disorder: comparison with schizophrenia

Both schizophrenia and bipolar disorder (BP) are associated with neurocognitive deficits. However, it has been suggested that schizophrenia, but not BP, is characterised by premorbid cognitive impairments and neurodevelopmental abnormalities. In this paper, studies investigating neurocognitive deficits in premorbid, high-risk and first-episode BP were reviewed and these findings were compared with outcome of studies in schizophrenia. Available evidence suggests that cognitive deficits are evident in first-episode BP and such deficits can be evident even years before the onset of the illness in some patients. Trajectory of cognitive deficits from childhood to adulthood can be very similar in schizophrenia and many patients with BP. Developmental lag in acquisition of cognitive skills is a risk factor for both disorders. However, unlike schizophrenia, not only impaired cognition but also supranormal premorbid cognitive/scholastic performance predict BP. Neurodevelopmental cognitive impairment is evident in some but not all patients with BP. A model suggesting that only BP patients who share common genetic risk factors with schizophrenia have premorbid neurodevelopmental cognitive deficits is proposed. In this model, combination of absence of neurodevelopmental abnormalities and BP-related temperamental characteristics explains the relationship between supranormal cognition and risk for BP.

Onset of maternal psychiatric disorders after the birth of a child with intellectual disability: a retrospective cohort study

Mothers of a child with intellectual disability (ID) have more psychiatric disorders after the birth of their child than other mothers. However, it is unclear if this is because they have more psychiatric disorders before the birth or if the increase is related to the burden of caring for the child. We aimed to calculate the rate of new psychiatric disorders in mothers after the birth of their eldest child with ID born between 1983 and 2005 and to compare these with rates in women with a child with no ID or autism spectrum disorder (ASD) born during the same period. By linking data from Western Australian population-based registries, we selected women with no psychiatric history who survived the birth of their live-born child (N = 277,559) and compared rates of psychiatric disorders for women with a child with ID and women without a child with or ASD. Negative binomial regression with STATA 12 was used for all analyses. Mothers of children with mild-moderate ID of unknown cause had around two to three and a half times the rate of psychiatric disorders of mothers of children without ID or ASD. Mothers of children with Down syndrome and no pre-existing psychiatric disorder showed resilience and had no impairments in their mental health. Interventions and services are needed for mothers of other children with ID to improve their mental health. Further research is implicated to explore the mental health of mothers of children with ID and a pre-existing psychiatric disorder.

Personality dysfunction is the cause of recurrent non-cognitive mental disorder: a testable hypothesis

OBJECTIVE

The objective of this study is to examine the evidence for a new hypothesis explaining the relationship between personality and mental state disorders.

DESIGN

At present, the attribution of personality disorder as a primary diagnosis only applies to patients who are antisocial, and particularly regarded as psychopathic, as in these patients, the mental state disorder that are associated are regarded in many respects as atypical and not representative of other mental disorders. The case is made in this paper that personality dysfunction lies behind the persistence of all non-cognitive mental disorders and that our failure to recognise this follows from our collective refusal to assess personality status early in life.

METHOD

Narrative review of relevant literature, which is limited as personality status is not often assessed early in life.

RESULTS

Support is adduced that personality dysfunction lies behind the persistence of all non-cognitive mental disorders (i.e. those that are not specifically neurodevelopmental and linked to cognitive impairment). The potential importance of this hypothesis is presented with regard to treatment and management strategy, emphasising that without specific intervention for personality dysfunction, many patients are destined for persistent morbidity.

Normal P50 Gating in Children with Autism, Yet Attenuated P50 Amplitude in the Asperger Subcategory

Autism spectrum disorders (ASD) and schizophrenia are separate disorders, but there is evidence of conversion or comorbid overlap. The objective of this paper was to explore whether deficits in sensory gating, as seen in some schizophrenia patients, can also be found in a group of ASD children compared to neurotypically developed children. An additional aim was to investigate the possibility of subdividing our ASD sample based on these gating deficits. In a case-control design, we assessed gating of the P50 and N100 amplitude in 31 ASD children and 39 healthy matched controls (8-12 years) and screened for differences between groups and within the ASD group. We did not find disturbances in auditory P50 and N100 filtering in the group of ASD children as a whole, nor did we find abnormal P50 and N100 amplitudes. However, the P50 amplitude to the conditioning stimulus was significantly reduced in the Asperger subgroup compared to healthy controls. In contrast to what is usually reported for patients with schizophrenia, we found no evidence for sensory gating deficits in our group of ASD children taken as a whole. However, reduced P50 amplitude to conditioning stimuli was found in the Asperger group, which is similar to what has been described in some studies in schizophrenia patients. There was a positive correlation between the P50 amplitude of the conditioning stimuli and anxiety score in the pervasive developmental disorder not otherwise specified group, which indicates a relation between anxiety and sensory registration in this group.

Bipolar Disorder in the Postpartum Period: Management Strategies and Future Directions

Bipolar I and II disorder are chronic and severe psychiatric illnesses that affect many women. Furthermore, women are at increased risk for mood episodes during the postpartum period compared with non-postpartum periods. Unfortunately, identification of clinically significant depressive or (hypo)manic episodes can be challenging. Delays in detection, as well as misdiagnosis, put women at risk of many negative consequences, such as symptom exacerbation and treatment refractoriness. Early and accurate detection of bipolar I or II disorder in the postpartum period is critical to improve prognosis. At this time, limited recommendations can be made due to a paucity of research. Further research on postpartum bipolar I or II disorder focusing on its identification, consequences and treatment is urgently needed to allow for empirically informed clinical decision-making.

An inherited duplication at the gene p21 Protein-Activated Kinase 7 (PAK7) is a risk factor for psychosis

Identifying rare, highly penetrant risk mutations may be an important step in dissecting the molecular etiology of schizophrenia. We conducted a gene-based analysis of large (>100 kb), rare copy-number variants (CNVs) in the Wellcome Trust Case Control Consortium 2 (WTCCC2) schizophrenia sample of 1564 cases and 1748 controls all from Ireland, and further extended the analysis to include an additional 5196 UK controls. We found association with duplications at chr20p12.2 (P = 0.007) and evidence of replication in large independent European schizophrenia (P = 0.052) and UK bipolar disorder case-control cohorts (P = 0.047). A combined analysis of Irish/UK subjects including additional psychosis cases (schizophrenia and bipolar disorder) identified 22 carriers in 11 707 cases and 10 carriers in 21 204 controls [meta-analysis Cochran-Mantel-Haenszel P-value = 2 × 10(-4); odds ratio (OR) = 11.3, 95% CI = 3.7, ∞]. Nineteen of the 22 cases and 8 of the 10 controls carried duplications starting at 9.68 Mb with similar breakpoints across samples. By haplotype analysis and sequencing, we identified a tandem ~149 kb duplication overlapping the gene p21 Protein-Activated Kinase 7 (PAK7, also called PAK5) which was in linkage disequilibrium with local haplotypes (P = 2.5 × 10(-21)), indicative of a single ancestral duplication event. We confirmed the breakpoints in 8/8 carriers tested and found co-segregation of the duplication with illness in two additional family members of one of the affected probands. We demonstrate that PAK7 is developmentally co-expressed with another known psychosis risk gene (DISC1) suggesting a potential molecular mechanism involving aberrant synapse development and plasticity.

De novo mutations in schizophrenia implicate chromatin remodeling and support a genetic overlap with autism and intellectual disability

Schizophrenia is a serious psychiatric disorder with a broadly undiscovered genetic etiology. Recent studies of de novo mutations (DNMs) in schizophrenia and autism have reinforced the hypothesis that rare genetic variation contributes to risk. We carried out exome sequencing on 57 trios with sporadic or familial schizophrenia. In sporadic trios, we observed a ~3.5-fold increase in the proportion of nonsense DNMs (0.101 vs 0.031, empirical P=0.01, Benjamini-Hochberg-corrected P=0.044). These mutations were significantly more likely to occur in genes with highly ranked probabilities of haploinsufficiency (P=0.0029, corrected P=0.006). DNMs of potential functional consequence were also found to occur in genes predicted to be less tolerant to rare variation (P=2.01 × 10(-)(5), corrected P=2.1 × 10(-)(3)). Genes with DNMs overlapped with genes implicated in autism (for example, AUTS2, CHD8 and MECP2) and intellectual disability (for example, HUWE1 and TRAPPC9), supporting a shared genetic etiology between these disorders. Functionally CHD8, MECP2 and HUWE1 converge on epigenetic regulation of transcription suggesting that this may be an important risk mechanism. Our results were consistent in an analysis of additional exome-based sequencing studies of other neurodevelopmental disorders. These findings suggest that perturbations in genes, which function in the epigenetic regulation of brain development and cognition, could have a central role in the susceptibility to, pathogenesis and treatment of mental disorders.

Association of a risk allele of ANK3 with cognitive performance and cortical thickness in patients with first-episode psychosis

BACKGROUND

The gene ANK3 is implicated in bipolar disorder and schizophrenia. The present study investigated the influence of this gene on cognitive performance and brain structure among individuals with first-episode psychosis (FEP). The brief illness duration of an FEP sample makes it well suited for studying the effects of genetic variation.

METHODS

We genotyped 2 single nucleotide polymorphisms (SNPs; rs1938526 and rs10994336) in ANK3 in patients with FEP. Multivariate analysis of variance compared risk allele carriers and noncarriers on 6 domains of cognition consistent with MATRICS consensus. A subsample of 82 patients was assessed using magnetic resonance imaging. We compared brain structure between carriers and noncarriers using cortical thickness analysis and voxel-based morphometry on white matter.

RESULTS

In the 173 patients with FEP included in our study, rs1938526 and rs10994336 were in very high linkage disequilibrium (d' = 0.95), and analyses were therefore only carried out on the SNP (rs1938526) with the highest minor allele frequency (G). Allele G of rs1938526, was associated with lower cognitive performance across domains (F6,164 = 2.38, p = 0.030) and significantly lower scores on the domains of verbal memory (p = 0.015), working memory (p = 0.006) and attention (p = 0.019). The significant effects of this SNP on cognition were not maintained when controlling for IQ. Cortical thinning was observed in risk allele carriers at diverse sites across cortical lobes bilaterally at a threshold of p < 0.01, false discovery rate-corrected. Risk-allele carriers did not show any regions of reduced white matter volume.

LIMITATIONS

The sample size is modest given that a low-frequency variant was being examined.

CONCLUSION

The ANK3 risk allele rs1938526 appears to be associated with general cognitive impairment and widespread cortical thinning in patients with FEP.

Both low birthweight and high birthweight are associated with cognitive impairment in persons with schizophrenia and their first-degree relatives

BACKGROUND

Both low birthweight and high birthweight have been associated with an increased risk for schizophrenia and cognitive impairments in the general population. We assessed the association between birthweight and cognitive performance in persons with schizophrenia and their unaffected first-degree relatives.

METHOD

We investigated a population-based family sample comprising persons with schizophrenia (n = 142) and their unaffected first-degree relatives (n = 277). Both patients and relatives were interviewed with the Structured Clinical Interview for DSM-IV Axis I Disorders, Clinician Version (SCID-CV) and a comprehensive neuropsychological test battery was administered. Information on birthweight was obtained from obstetric records. We used generalized estimating equation (GEE) models to investigate the effect of birthweight, as a continuous variable, on cognitive functioning, adjusting for within-family correlation and relevant covariates.

RESULTS

Both low birthweight and high birthweight were associated with lower performance in visuospatial reasoning, processing speed, set-shifting and verbal and visual working memory among persons with schizophrenia and their unaffected first-degree relatives compared to individuals with birthweight in the intermediate range. The group × birthweight interactions were non-significant.

CONCLUSIONS

Both low birthweight and high birthweight are associated with deficits in cognition later in life. Schizophrenia does not seem to modify the relationship between birthweight and cognition in families with schizophrenia.

Trends in pre-existing mental health disorders among parents of infants born in Western Australia from 1990 to 2005

OBJECTIVE

To determine the prevalence of prior and current mental health disorders in parents, including trends over time.

DESIGN

retrospective population cohort study using de-identified linked health data.

SETTING

Population of Western Australia.

SUBJECTS

All parents of infants born in WA between 1990 and 2005.

MAIN OUTCOME MEASURES

Prevalence of prior mental health disorders in parents by birth 2013 and by parent and child characteristics, including Aboriginality, maternal age, socioeconomic status and diagnostic groups.

RESULTS

From 1990 to 2005, there was an increase in prevalence of prior mental health disorders in mothers, from 76 per 1000 births in 1990 to 131 per 1000 births in 2005 (3.7% increase per 2013 in the odds of children being born to mothers with a prior mental health disorder). There was also a 4.7% increase in odds per 2013 in the prevalence of mental health contacts that had taken place in the 12 months before the birth 2013 in mothers. In addition, there was an increase in prevalence of prior mental health disorders in fathers, from 56 per 1000 births in 1990 to 88 per 1000 births in 2005 (3.1% increase in odds per 2013). The diagnostic group with the highest prevalence in both mothers and fathers was substance-related disorders.

CONCLUSIONS

From 1990 to 2005, there was an increase in prevalence of parents with a prior history of mental health disorders in WA. General practitioners and mental health workers can play an important role in identifying mental illness and in working with families to offer early intervention, referral and support.

Parental psychiatric disorders and autism spectrum disorders

The present population-based, case-control study examines associations between specific parental psychiatric disorders and autism spectrum disorders (ASD) including childhood autism, Asperger's syndrome and pervasive developmental disorder (PDD-NOS). The cohort includes 4713 children born between 1987 and 2005 with diagnoses of childhood autism, Asperger's syndrome or PDD-NOS. Cases were ascertained from the Finnish Hospital Discharge Register, and each was matched to four controls by gender, date of birth, place of birth, and residence in Finland. Controls were selected from the Finnish Medical Birth Register. Parents were identified through the Finnish Medical Birth Register and Finnish Central Population Register. Parental psychiatric diagnoses from inpatient care were collected from the Finnish Hospital Discharge Register. Conditional logistic regression models were used to assess whether parents' psychiatric disorders predicted ASD after controlling for parents' age, smoking during pregnancy and weight for gestational age. In summary, parental schizophrenia spectrum disorders and affective disorders were associated with the risk of ASD regardless of the subgroup. PDD-NOS was associated with all parental psychiatric disorders investigated. Further studies are needed to replicate these findings. These results may facilitate the investigation of shared genetic and familial factors between ASD and other psychiatric disorders.

Antidepressant therapy in epilepsy: can treating the comorbidities affect the underlying disorder?

There is a high incidence of psychiatric comorbidity in people with epilepsy (PWE), particularly depression. The manifold adverse consequences of comorbid depression have been more clearly mapped in recent years. Accordingly, considerable efforts have been made to improve detection and diagnosis, with the result that many PWE are treated with antidepressant drugs, medications with the potential to influence both epilepsy and depression. Exposure to older generations of antidepressants (notably tricyclic antidepressants and bupropion) can increase seizure frequency. However, a growing body of evidence suggests that newer ('second generation') antidepressants, such as selective serotonin reuptake inhibitors or serotonin-noradrenaline reuptake inhibitors, have markedly less effect on excitability and may lead to improvements in epilepsy severity. Although a great deal is known about how antidepressants affect excitability on short time scales in experimental models, little is known about the effects of chronic antidepressant exposure on the underlying processes subsumed under the term 'epileptogenesis': the progressive neurobiological processes by which the non-epileptic brain changes so that it generates spontaneous, recurrent seizures. This paper reviews the literature concerning the influences of antidepressants in PWE and in animal models. The second section describes neurobiological mechanisms implicated in both antidepressant actions and in epileptogenesis, highlighting potential substrates that may mediate any effects of antidepressants on the development and progression of epilepsy. Although much indirect evidence suggests the overall clinical effects of antidepressants on epilepsy itself are beneficial, there are reasons for caution and the need for further research, discussed in the concluding section.