Obstetric complications as antecedents of schizophrenia: empirical effects of using different obstetric complication scales

The interaction between early life complications and a polygenic risk score for schizophrenia is associated with brain activity during emotion processing in healthy participants

BACKGROUND

Previous evidence suggests that early life complications (ELCs) interact with polygenic risk for schizophrenia (SCZ) in increasing risk for the disease. However, no studies have investigated this interaction on neurobiological phenotypes. Among those, anomalous emotion-related brain activity has been reported in SCZ, even if evidence of its link with SCZ-related genetic risk is not solid. Indeed, it is possible this relationship is influenced by non-genetic risk factors. Thus, this study investigated the interaction between SCZ-related polygenic risk and ELCs on emotion-related brain activity.

METHODS

169 healthy participants (HP) in a discovery and 113 HP in a replication sample underwent functional magnetic resonance imaging (fMRI) during emotion processing, were categorized for history of ELCs and genome-wide genotyped. Polygenic risk scores (PRSs) were computed using SCZ-associated variants considering the most recent genome-wide association study. Furthermore, 75 patients with SCZ also underwent fMRI during emotion processing to verify consistency of their brain activity patterns with those associated with risk factors for SCZ in HP.

RESULTS

Results in the discovery and replication samples indicated no effect of PRSs, but an interaction between PRS and ELCs in left ventrolateral prefrontal cortex (VLPFC), where the greater the activity, the greater PRS only in presence of ELCs. Moreover, SCZ had greater VLPFC response than HP.

CONCLUSIONS

These results suggest that emotion-related VLPFC response lies in the path from genetic and non-genetic risk factors to the clinical presentation of SCZ, and may implicate an updated concept of intermediate phenotype considering early non-genetic factors of risk for SCZ.

Interactions Between Genetic, Prenatal Substance Use, Puberty, and Parenting are Less Important for Understanding Adolescents' Internalizing, Externalizing, and Substance Use than Developmental Cascades in Multifactorial Models

This study tested interactions among puberty-related genetic risk, prenatal substance use, harsh discipline, and pubertal timing for the severity and directionality (i.e., differentiation) of externalizing and internalizing problems and adolescent substance use. This is a companion paper to Marceau et al. (2021) which examined the same influences in developmental cascade models. Data were from the Avon Longitudinal Study of Parents and Children (ALSPAC) cohort (n = 4504 White boys, n = 4287 White girls assessed from the prenatal period through 18.5 years). We hypothesized generally that later predictors would strengthen the influence of puberty-related genetic risk, prenatal substance use exposure, and pubertal risk on psychopathology and substance use (two-way interactions), and that later predictors would strengthen the interactions of earlier influences on psychopathology and substance use (three-way interactions). Interactions were sparse. Although all fourteen interactions showed that later influences can exacerbate or trigger the effects of earlier ones, they often were not in the expected direction. The most robust moderator was parental discipline, and differing and synergistic effects of biological and socially-relevant aspects of puberty were found. In all, the influences examined here operate more robustly in developmental cascades than in interaction with each other for the development of psychopathology and transitions to substance use.

Examination of promotive and protective effects on early adolescent prosocial behavior through a bioecological lens

Introduction

Prosocial behavior during childhood has been associated with numerous positive developmental and behavioral outcomes in adolescence and adulthood. Prosocial behavior, which includes cooperation and helping others, develops within a bioecological context. Considering it through such a lens enhances the understanding of the roles of different bioecological factors in its development.

Methods

Using data from a longitudinal study of adopted children and children reared with their biological parents, this paper examined if positive aspects of a child's bioecological system at age 7 predict prosocial behavior in early adolescence (age 11), and whether these bioecological factors could offset risk due to biological family psychopathology and/or maternal prenatal substance use. The analyses incorporated variables from different levels of Bronfenbrenner's bioecological model (the individual, microsystem, exosystem, and macrosystem) and examined the promotive, and potentially protective, effect of each contextual factor, while also considering their interplay with biological family psychopathology and prenatal substance use.

Results

Results from linear regression models indicated that the microsystem variable of parental warmth at age 7 had a promotive effect on age 11 prosocial behavior. Further, in addition to its main effect, parental warmth was protective against maternal substance use during pregnancy when children were raised with their biological parent (s). Household type (biological family) and biological family internalizing psychopathology were the only other significant predictors in the model, with each associated with lower prosocial behavior at age 11.

Discussion

Study results extend prior work on the benefits of parental warmth on child outcomes by employing a strength-based, bioecological approach to the development of prosocial behavior during early adolescence and examining "for whom" the effects of parental warmth are most protective.

Within-person associations of cortisol, dehydroepiandrosterone, and testosterone hair hormone concentrations and psychological distress in pregnant and non-pregnant women

Prenatal hair cortisol concentration is inconsistently associated with maternal psychological distress. However, prior studies have not often measured hair cortisol and maternal psychological distress prospectively over time, examined within-person associations, nor concurrently considered the complex hormonal milieu in which cortisol operates during pregnancy. We addressed these limitations and tested associations against a similar non-pregnant comparison group. Participants included 68 women (34 pregnant and 34 non-pregnant; Mage = 29.14 and 83 % White) from the Midwestern United States. Pregnant women were assessed each trimester, at 12, 26, and 38 weeks and non-pregnant women were assessed three times on the same schedule. At each assessment, participants completed measures of psychological distress and provided hair samples. The first 3 cm (from the scalp) of hair was assayed using enzyme immune-assay kits to reflect cumulative levels within the given trimester/3-month time period of cortisol, dehydroepiandrosterone (DHEA) and testosterone. Within-person associations of hair cortisol and ratio of hair cortisol-to-DHEA and cortisol-to-testosterone with psychological distress were assessed using multilevel models. There were positive within-person associations of hair cortisol with cumulative psychological distress (γ = 0.01, s.e. = 0.003, p = .049), anxiety (γ = 0.09, s.e. = 0.04, p = .046), and pregnancy-related anxiety symptoms (γ = 0.10, s.e. = 0.05, p = .041) in the pregnant sample such that on occasions when hair cortisol was higher than average so were psychological distress symptoms. No within-person associations of hair cortisol were supported in non-pregnant women although there was a negative within-person association, such that on occasions of having lower testosterone level than typical, depression symptoms were higher. There were no within-person associations of psychological distress and cortisol-to-DHEA ratio or cortisol-to-testosterone ratio in either the pregnant or non-pregnant sample. At the between person-level for pregnant women, lower cortisol levels were associated with higher perceived stress (γ = -0.28, s.e. = 0.09, p = .003) and depression symptoms (γ = -0.11, s.e. = 0.06, p = .039), whereas higher cortisol levels were associated with higher psychological distress (γ = 0.03, s.e. = 0.01, p = .010), state anxiety (γ = 0.33, s.e. = 0.13, p = .010), and depression symptoms (γ = 0.23, s.e. = 0.09, p = .017) in non-pregnant women. Modeling hair cortisol at the within-person and between-person level revealed differential findings in pregnant and non-pregnant women. Hair cortisol concentration, psychological distress, pregnancy, hormone coupling, within-person associations.

Reliability of prospective and retrospective maternal reports of prenatal experiences

BACKGROUND

Extant perinatal research utilizes retrospective reports on the prenatal environment, but there are limited data on the validity of retrospective data compared with prospective data. The current study examined the reliability of birth mothers' memory of prenatal stress and distress and perinatal risks at 6-months postpartum with maternal reports gathered across each trimester of pregnancy and explored whether recall varied with maternal socioeconomic status.

METHODS

Surveys were collected from 34 pregnant women (M age = 29.14, SD = 5.06 years, 83% non-Hispanic White) on stress, distress, and pregnancy complications at 12(T1), 26(T2), and 38(T3) weeks of pregnancy, and at 6-month post-partum asking the same questions but specifically about the pregnancy. Cohen's kappa and Pearson's correlations were used to investigate maternal recall at post-partum with prospective reports at T1, T2, T3 and an average score of T1, T2, and T3. Correlations were also examined separately for those with high and relatively lower socioeconomic status.

RESULTS

Birth mothers' recall was generally reliable. Retrospective reports were most strongly related to prospective reports in T1 for perceived stress, T1 and T3 for anxiety symptoms and exposure to toxins, but T3 for depressive symptoms. Recall of pregnancy complications best reflected the average score across trimesters (rather than specific trimesters). Women with higher socioeconomic status better recalled prenatal (di)stress, but women with relatively lower socioeconomic status better recalled exposure to toxins.

CONCLUSION

This study provides support for utilizing retrospective reports of maternal prenatal experiences at 6-months post-partum, with implications for interpretation of specific recalled phenotypes.

Asphyxia at birth affects brain structure in patients on the schizophrenia-bipolar disorder spectrum and healthy participants

BACKGROUND

Uncertainty exists about what causes brain structure alterations associated with schizophrenia (SZ) and bipolar disorder (BD). Whether a history of asphyxia-related obstetric complication (ASP) - a common but harmful condition for neural tissue - contributes to variations in adult brain structure is unclear. We investigated ASP and its relationship to intracranial (ICV), global brain volumes and regional cortical and subcortical structures.

METHODS

A total of 311 patients on the SZ - BD spectrum and 218 healthy control (HC) participants underwent structural magnetic resonance imaging. They were evaluated for ASP using prospective information obtained from the Medical Birth Registry of Norway.

RESULTS

In all groups, ASP was related to smaller ICV, total brain, white and gray matter volumes and total surface area, but not to cortical thickness. Smaller cortical surface areas were found across frontal, parietal, occipital, temporal and insular regions. Smaller hippocampal, amygdala, thalamus, caudate and putamen volumes were reported for all ASP subgroups. ASP effects did not survive ICV correction, except in the caudate, which remained significantly smaller in both patient ASP subgroups, but not in the HC.

CONCLUSIONS

Since ASP was associated with smaller brain volumes in all groups, the genetic risk of developing a severe mental illness, alone, cannot easily explain the smaller ICV. Only the smaller caudate volumes of ASP patients specifically suggest that injury from ASP can be related to disease development. Our findings give support for the ICV as a marker of aberrant neurodevelopment and ASP in the etiology of brain development in BD and SZ.

Early manifestations of intellectual performance: Evidence that genetic effects on later academic test performance are mediated through verbal performance in early childhood

Intellectual performance is highly heritable and robustly predicts lifelong health and success but the earliest manifestations of genetic effects on this asset are not well understood. This study examined whether early executive function (EF) or verbal performance mediate genetic influences on subsequent intellectual performance, in 561 U.S.-based adoptees (57% male) and their birth and adoptive parents (70% and 92% White, 13% and 4% African American, 7% and 2% Latinx, respectively), administered measures in 2003-2017. Genetic influences on children's academic performance at 7 years were mediated by verbal performance at 4.5 years (β = .22, 95% CI [0.08, 0.35], p = .002) and not via EF, indicating that verbal performance is an early manifestation of genetic propensity for intellectual performance.

Lack of Support for the Genes by Early Environment Interaction Hypothesis in the Pathogenesis of Schizophrenia

Ursini et al reported recently that the liability of schizophrenia explained by a polygenic risk score (PRS) derived from the variants most associated with schizophrenia was increased 5-fold in individuals who experienced complications during pregnancy or birth. Follow-up gene expression analysis showed that the genes mapping to the most associated genetic variants are highly expressed in placental tissues. If confirmed, these findings will have major implications in our understanding of the joint effect of genes and environment in the pathogenesis of schizophrenia. We examined the interplay between PRS and obstetric complications (OCs) in 5 independent samples (effective N = 2110). OCs were assessed with the full or modified Lewis-Murray scale, or with birth weight < 2.5 kg as a proxy. In a large cohort we tested whether the pathways from placenta-relevant variants in the original report were associated with case-control status. Unlike in the original study, we did not find significant effect of PRS on the presence of OCs in cases, nor a substantial difference in the association of PRS with case-control status in samples stratified by the presence of OCs. Furthermore, none of the PRS by OCs interactions were significant, nor were any of the biological pathways, examined in the Swedish cohort. Our study could not support the hypothesis of a mediating effect of placenta biology in the pathway from genes to schizophrenia. Methodology differences, in particular the different scales measuring OCs, as well as power constraints for interaction analyses in both studies, may explain this discrepancy.

Examining reciprocal associations between parent depressive symptoms and child internalizing symptoms on subsequent psychiatric disorders: An adoption study

INTRODUCTION

The dynamic interplay between parent depressive symptoms and child internalizing behavior over time is not well understood.

METHODS

We used data from a prospective parent-offspring adoption design (N = 561) to examine associations between adoptive parent depressive symptoms and child internalizing behavior when children were ages 18 months, 27 months, 4.5 years, and 6 years, and subsequent child psychiatric disorder symptoms when children were between the ages of 6-8 years. Models also accounted for the contributions of birth parent psychopathology, birth mother depressive symptoms during pregnancy, and infant negative emotionality. Bidirectional associations between adoptive parent depressive symptoms and child internalizing behavior were examined using a random-intercept cross-lagged panel model.

RESULTS

There was evidence for associations between child internalizing behavior and adoptive parent depressive symptoms over time, with mothers' depressive symptoms being a more salient risk factor for child internalizing behavior than fathers'. We found one significant cross-lagged association from adoptive mother depressive symptoms at child age 18 months to child internalizing behavior at age 27 months. Infant negative emotionality (i.e., emotional liability) at age 9 months predicted both child internalizing behavior and adoptive parent depressive symptoms.

CONCLUSION

Results suggest that postnatal maternal depressive symptoms confer specific risks for child internalizing behaviors in toddlerhood and childhood and depressive symptoms in childhood.

Developmental Cascades from Polygenic and Prenatal Substance Use to Adolescent Substance Use: Leveraging Severity and Directionality of Externalizing and Internalizing Problems to Understand Pubertal and Harsh Discipline-Related Risk

The current study leveraged the Avon Longitudinal Study of Parents and Children (ALSPAC) cohort (n = 4504 White boys, n = 4287 White girls assessed from the prenatal period through 18.5 years of age) to test a developmental cascade from genetic and prenatal substance use through pubertal timing and parenting to the severity of (regardless of type) and directionality (i.e., differentiation) of externalizing and internalizing problems to adolescent substance use. Limited associations of early pubertal timing with substance use outcomes were only observable via symptom directionality, differently for girls and boys. For boys, more severe exposure to prenatal substance use influenced adolescent substance use progression via differentiation towards relatively more pure externalizing problems, but in girls the associations were largely direct. Severity and especially directionality (i.e., differentiation towards relatively more pure externalizing problems) were key intermediaries in developmental cascades from parental harsh discipline with substance use progressions for girls and boys.

The role of negative emotionality in the development of child executive function and language abilities from toddlerhood to first grade: An adoption study

Understanding the role of negative emotionality in the development of executive functioning (EF) and language skills can help identify developmental windows that may provide promising opportunities for intervention. In addition, because EF and language skills are, in part, genetically influenced, intergenerational transmission patterns are important to consider. The prospective parent-offspring adoption design used in this study provides a unique opportunity to examine the intergenerational transmission of EF and language skills. Participants were 561 children adopted around the time of birth. Accounting for birth mother EF and language contributions, we examined the role of child negative emotionality in toddlerhood (age 9 to 27 months) and childhood (age 4.5 to 7 years) on child EF and language skills in first grade (age 7 years). There was continuity in EF from age 27 months to 7 years, and in language ability from age 27 months to 7 years, with no cross-lagged effects between child EF and language ability. Negative emotionality at age 9 months predicted lower EF and lower language abilities at age 7 years, and growth in negative emotionality from age 4.5 to 7 years predicted lower child EF at age 7 years. Overall, findings suggested that lower negative emotionality at age 9 months was associated with higher toddler and child EF and language skills and that preventing growth in negative emotionality from age 4.5 to 7 years may lead to improvements in child EF. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Callous-Unemotional Behaviors and Harsh Parenting: Reciprocal Associations across Early Childhood and Moderation by Inherited Risk

Callous-unemotional (CU) behaviors increase children's risk for subsequent antisocial behavior. This risk process may begin in early childhood with reciprocal pathways between CU behaviors and harsh parenting. In a sample of 561 linked triads of biological mothers, adoptive parents, and adopted children, the present study examined bidirectional links between CU behaviors and harsh parenting across three time points from 18 to 54 months and investigated moderation by inherited risk for psychopathic traits. Child CU behaviors and harsh parenting were measured using adoptive mother and adoptive father reports, and biological mothers provided reports of their personality characteristics. Findings supported reciprocal associations between harsh parenting and CU behaviors during early childhood, especially during the transition from toddlerhood (27 months) to the preschool period (54 months). Moreover, multiple-group analyses showed that level of inherited risk moderated associations between CU behaviors and harsh parenting. Specifically, there were statistically reliable associations between CU behaviors at 27 months and adoptive mothers' harsh parenting at 54 months, and between adoptive fathers' harsh parenting at 27 months and CU behaviors at 54 months among children at higher inherited risk, but not among those at lower inherited risk. The findings illustrate the dynamic interplay between parenting, CU behaviors, and heritable risk.

Obstetric complications and intelligence in patients on the schizophrenia-bipolar spectrum and healthy participants

BACKGROUND

Whether severe obstetric complications (OCs), which harm neural function in offspring, contribute to impaired cognition found in psychiatric disorders is currently unknown. Here, we sought to evaluate how a history of severe OCs is associated with cognitive functioning, indicated by Intelligence Quotient (IQ).

METHODS

We evaluated the associations of a history of OCs and IQ in 622 healthy controls (HC) and 870 patients on the schizophrenia (SCZ) - bipolar disorder (BIP) spectrum from the ongoing Thematically Organized Psychosis study cohort, Oslo, Norway. Participants underwent assessments using the NART (premorbid IQ) and the WASI (current IQ). Information about OCs was obtained from the Medical Birth Registry of Norway. Multiple linear regression models were used for analysis.

RESULTS

Severe OCs were equally common across groups. SCZ patients with OCs had lower performances on both premorbid and current IQ measures, compared to those without OCs. However, having experienced more than one co-occurring severe OC was associated with lower current IQ in all groups.

CONCLUSIONS

Severe OCs were associated with lower IQ in the SCZ group and in the BIP and HC groups, but only if they had experienced more than one severe OC. Low IQ might be a neurodevelopmental marker for SCZ; wherein, severe OCs influence cognitive abilities and increase the risk of developing SCZ. Considering OCs as a variable of neurodevelopmental risk for severe mental illness may promote the development of neuroprotective interventions, improve outcome in vulnerable newborns and advance our ability to make clinical prognoses.

Neurodevelopmental concepts of schizophrenia in the genome-wide association era: AKT/mTOR signaling as a pathological mediator of genetic and environmental programming during development

Normative brain development is contingent on the complex interplay between genes and environment. Schizophrenia (SCZ) is considered a highly polygenic, neurodevelopmental disorder associated with impaired neural circuit development, neurocognitive function and variations in neurotransmitter signaling systems, including dopamine. Significant evidence, accumulated over the last 30 years indicates a role for the in utero environment in SCZ pathophysiology. Emerging data suggests that changes in placental programming and function may mediate the link between genetic risk, early life complications (ELC) and adverse neurodevelopmental outcomes, with risk highlighted in key developmental drivers that converge on AKT/mTOR signaling. In this article we overview select risk genes identified through recent genome-wide association studies of SCZ including AKT3, miR-137, DRD2, and AKT1 itself. We propose that through convergence on AKT/mTOR signaling, these genes are critical factors directing both placentation and neurodevelopment, influencing risk for SCZ through dysregulation of placental function, metabolism and early brain development. We discuss association of risk genes in the context of their known roles in neurodevelopment, placental expression and their possible mechanistic links to SCZ in the broad context of the 'developmental origins of adult disease' construct. Understanding how common genetic variation impacts early fetal programming may advance our knowledge of disease etiology and identify early critical developmental windows for prevention and intervention.

Heritable temperament pathways to early callous-unemotional behaviour

BACKGROUND

Early callous-unemotional behaviours identify children at risk for antisocial behaviour. Recent work suggests that the high heritability of callous-unemotional behaviours is qualified by interactions with positive parenting.

AIMS

To examine whether heritable temperament dimensions of fearlessness and low affiliative behaviour are associated with early callous-unemotional behaviours and whether parenting moderates these associations.

METHOD

Using an adoption sample (n = 561), we examined pathways from biological mother self-reported fearlessness and affiliative behaviour to child callous-unemotional behaviours via observed child fearlessness and affiliative behaviour, and whether adoptive parent observed positive parenting moderated pathways.

RESULTS

Biological mother fearlessness predicted child callous-unemotional behaviours via earlier child fearlessness. Biological mother low affiliative behaviour predicted child callous-unemotional behaviours, although not via child affiliative behaviours. Adoptive mother positive parenting moderated the fearlessness to callous-unemotional behaviour pathway.

CONCLUSIONS

Heritable fearlessness and low interpersonal affiliation traits contribute to the development of callous-unemotional behaviours. Positive parenting can buffer these risky pathways.

Ankyrin-3 as a molecular marker of early-life stress and vulnerability to psychiatric disorders

Exposure to early-life stress (ELS) may heighten the risk for psychopathology at adulthood. Here, in order to identify common genes that may keep the memory of ELS through changes in their methylation status, we intersected methylome analyses performed in different tissues and time points in rats, non-human primates and humans, all characterized by ELS. We identified Ankyrin-3 (Ank3), a scaffolding protein with a strong genetic association for psychiatric disorders, as a gene persistently affected by stress exposure. In rats, Ank3 methylation and mRNA changes displayed a specific temporal profile during the postnatal development. Moreover, exposure to prenatal stress altered the interaction of ankyrin-G, the protein encoded by Ank3 enriched in the post-synaptic compartment, with PSD95. Notably, to model in humans a gene by early stress interplay on brain phenotypes during cognitive performance, we demonstrated an interaction between functional variation in Ank3 gene and obstetric complications on working memory in healthy adult subjects. Our data suggest that alterations of Ank3 expression and function may contribute to the effects of ELS on the development of psychiatric disorders.

Heritable and Nonheritable Pathways to Early Callous-Unemotional Behaviors

OBJECTIVE

Callous-unemotional behaviors in early childhood signal higher risk for trajectories of antisocial behavior and callous-unemotional traits that culminate in later diagnoses of conduct disorder, antisocial personality disorder, and psychopathy. Studies demonstrate high heritability of callous-unemotional traits, but little research has examined specific heritable pathways to early callous-unemotional behaviors. Studies also indicate that positive parenting protects against the development of callous-unemotional traits, but genetically informed designs have not been used to confirm that these relationships are not the product of gene-environment correlations. In a sample of adopted children and their biological and adoptive mothers, the authors tested novel heritable and nonheritable pathways to preschool callous-unemotional behaviors.

METHOD

In an adoption cohort of 561 families, history of severe antisocial behavior assessed in biological mothers and observations of adoptive mother positive reinforcement at 18 months were examined as predictors of callous-unemotional behaviors at 27 months.

RESULTS

Despite limited or no contact with offspring, biological mother antisocial behavior predicted early callous-unemotional behaviors. Adoptive mother positive reinforcement protected against early callous-unemotional behaviors. High levels of adoptive mother positive reinforcement buffered the effects of heritable risk for callous-unemotional behaviors posed by biological mother antisocial behavior.

CONCLUSIONS

The findings elucidate heritable and nonheritable pathways to early callous-unemotional behaviors. The results provide a specific heritable pathway to callous-unemotional behaviors and compelling evidence that parenting is an important nonheritable factor in the development of callous-unemotional behaviors. The finding that positive reinforcement buffered heritable risk for callous-unemotional behaviors has important translational implications for the prevention of trajectories to serious antisocial behavior.

Estimating the Roles of Genetic Risk, Perinatal Risk, and Marital Hostility on Early Childhood Adjustment: Medical Records and Self-Reports

A wide variety of perinatal risk factors have been linked to later developmental outcomes in children. Much of this work has relied on either birth/medical records or mothers' self-reports collected after delivery, and there has been an ongoing debate about which strategy provides the most accurate and reliable data. This report uses a parent-offspring adoption design (N = 561 families) to (1) examine the correspondence between medical record data and self-report data, (2) examine how perinatal risk factors may influence child internalizing and externalizing behavior at age 4.5 years, and (3) explore interactions among genetic, perinatal risk, and rearing environment on child internalizing and externalizing behavior during early childhood. The agreement of self-reports and medical records data was relatively high (51-100 %), although there was some variation based on the construct. There were few main effects of perinatal risk on child outcomes; however, there were several 2- and 3-way interactions suggesting that the combined influences of genetic, perinatal, and rearing environmental risks are important, particularly for predicting whether children exhibit internalizing versus externalizing symptoms at age 4.5 years.

The Perinatal Risk Index: Early Risks Experienced by Domestic Adoptees in the United States

We aimed to assess comprehensively the prevalence of perinatal risks experienced by a potentially high-risk yet understudied population of children domestically adopted in the United States. Data are from participant report and medical records from mothers (n = 580) who completed a domestic adoption placement with nonrelatives at or near birth (Mean placement age = 7 days). We describe a comprehensive measure of perinatal risks, including divergences from previous assessment tools and the incorporation of multiple reporters, and report the prevalence of various types of perinatal risks. The prevalence of each specific risk factor was generally low, although several risks were more prevalent in this sample than estimates from nationally representative publicly available data. Nearly the entire sample (99%) experienced some type of risk exposure. Birth mothers who placed their children for adoption domestically in the US experience higher levels of perinatal risks than the national average, but not for all specific types of risk. Thus, the developmental trajectories of children adopted domestically may systematically differ from the general population to the extent that these specific perinatal risks impact development.

The Development of Early Profiles of Temperament: Characterization, Continuity, and Etiology

This study used a data-driven, person-centered approach to examine the characterization, continuity, and etiology of child temperament from infancy to toddlerhood. Data from 561 families who participated in an ongoing prospective adoption study, the Early Growth and Development Study, were used to estimate latent profiles of temperament at 9, 18, and 27 months. Results indicated that four profiles of temperament best fit the data at all three points of assessment. The characterization of profiles was stable over time, while membership in profiles changed across age. Facets of adoptive parent and birth mother personality were predictive of children's profile membership at each age, providing preliminary evidence for specific environmental and genetic influences on patterns of temperament development from infancy to toddlerhood.

Toward an Understanding of the Role of the Environment in the Development of Early Callous Behavior

Key to understanding the long-term impact of social inequalities is identifying early behaviors that may signal higher risk for later poor psychosocial outcomes, such as psychopathology. A set of early-emerging characteristics that may signal risk for later externalizing psychopathology is callous-unemotional (CU) behavior. CU behavior predicts severe and chronic trajectories of externalizing behaviors in youth. However, much research on CU behavior has focused on late childhood and adolescence, with little attention paid to early childhood when preventative interventions may be most effective. In this article, we summarize our recent work showing that (a) CU behavior can be identified in early childhood using items from common behavior checklists, (b) CU behavior predicts worse outcomes across early childhood, (c) CU behavior exhibits a nomological network distinct from other early externalizing behaviors, and (d) malleable environmental factors, particularly parenting, may play a role in the development of early CU behaviors. We discuss the challenges of studying contextual contributors to the development of CU behavior in terms of gene-environment correlations and present initial results from work examining CU behavior in an adoption study in which gene-environment correlations are examined in early childhood. We find that parenting is a predictor of early CU behavior even in a sample in which parents are not genetically related to the children.

Obstetric complications and eating disorders: a replication study

OBJECTIVE

To provide data about the role of obstetric complications (OCs) in a large and well-characterized sample of patients with anorexia nervosa (AN) or bulimia nervosa (BN).

METHOD

The new sample consists of 150 patients with AN and 35 patients with BN, and 73 healthy women; statistical analyses were performed on the new sample alone and on the larger sample created by merging the new dataset with the previous one (264 AN, 108 BN, and 624 healthy women). All data about OCs were collected blind to diagnostic status.

RESULTS

OC rates in the replication sample were similar to those of our previous studies. In the whole sample, the risk of developing AN was significantly associated with the occurrence and number of pregnancy, delivery, hypoxic, and dysmaturity complications. The risk of developing BN was significantly associated with dysmaturity complications. Signs of retarded fetal growth (being small and short for gestational age, short head circumference) significantly distinguished BN patients from both AN and healthy individuals. Significantly higher number of OCs were found in the binge eating/purging type of AN, in comparison with restricting AN patients.

DISCUSSION

Our study provides further evidence of the role of OCs as putative risk factors for the development of eating disorders, showing different pathways between AN and BN.

Transactional Patterns of Maternal Depressive Symptoms and Mother-Child Mutual Negativity in an Adoption Sample

Transactional models of analysis can examine both moment-to-moment interactions within a dyad and dyadic patterns of influence across time. This study used data from a prospective adoption study to test a transactional model of parental depressive symptoms and mutual negativity between mother and child over time, utilizing contingency analysis of second-by-second behavioral data. To consider both genetic and environmental influences on mutual negativity, depressive symptoms were examined in both adoptive and birth mothers. Adoptive mother depressive symptoms at 9 months increased the likelihood that, at 18 months, children reacted negatively to their mothers' negative behavior, which in turn predicted higher levels of adoptive mother depressive symptoms at 27 months, suggesting that over time, mothers' depressive symptoms influence and are influenced by moment-to-moment mutual negativity with their toddlers. Birth mother depressive symptoms moderated the association between mutual negativity at 18 months and adoptive mother depressive symptoms at 27 months, suggesting a child-driven contribution to maternal depressive symptoms that can be measured by a genetic sensitivity.

Neural correlates of prenatal stress in young women

BACKGROUND

Prenatal stress is hypothesized to have a disruptive impact on neurodevelopmental trajectories, but few human studies have been conducted on the long-term neural correlates of prenatal exposure to stress. The aim of this study was to explore the relationship between prenatal stress exposure and gray-matter volume and resting-state functional connectivity in a sample of 35 healthy women aged 14-40 years.

METHOD

Voxel-based morphometry and functional connectivity analyses were performed on the whole brain and in specific regions of interest (hippocampus and amygdala). Data about prenatal/postnatal stress and obstetric complications were obtained by interviewing participants and their mothers, and reviewing obstetric records.

RESULTS

Higher prenatal stress was associated with decreased gray-matter volume in the left medial temporal lobe (MTL) and both amygdalae, but not the hippocampus. Variance in gray-matter volume of these brain areas significantly correlated with depressive symptoms, after statistically adjusting for the effects of age, postnatal stress and obstetric complications. Prenatal stress showed a positive linear relationship with functional connectivity between the left MTL and the pregenual cortex. Moreover, connectivity between the left MTL and the left medial-orbitofrontal cortex partially explained variance in the depressive symptoms of offspring.

CONCLUSIONS

In young women, exposure to prenatal stress showed a relationship with the morphometry and functional connectivity of brain areas involved in the pathophysiology of depressive disorders. These data provide evidence in favor of the hypothesis that early exposure to stress affects brain development and identified the MTL and amygdalae as possible targets of such exposure.

Angry responses to infant challenges: parent, marital, and child genetic factors associated with harsh parenting

This study examined genetic and environmental influences on harsh parenting of adopted 9-month-olds (N = 503), with an emphasis on positive child-, parent-, and family-level characteristics. Evocative gene-environment correlation (rGE) was examined by testing the effect of both positive and negative indices of birth parent temperament on adoptive parents' harsh parenting. Adoptive fathers' harsh parenting was inversely related to birth mother positive temperament, indicating evocative rGE, as well as to marital quality. Adoptive parents' negative temperamental characteristics were related to hostile parenting for both fathers and mothers. Findings support the importance of enhancing positive family characteristics in addition to mitigating negative characteristics, as well as engaging multiple levels of the family system to prevent harsh parenting.

Effects of obstetric complications on volume and functional connectivity of striatum in anorexia nervosa patients

OBJECTIVE

To investigate the volume and functional connectivity of dorsal and ventral striatal nuclei in anorexia nervosa (AN) and their relationship with early exposure to obstetric complications.

METHOD

Fifty-one patients with lifetime AN (35 acute, 16 recovered) and 34 healthy controls underwent high-resolution and resting-state functional magnetic resonance imaging.

RESULTS

The AN group showed reduced functional connectivity of the putamen compared with healthy women, and this reduction was more evident in patients with lifetime binge eating/purging. Both acute and recovered AN groups showed a larger left accumbens area compared with that of healthy women. The functional connectivity of bilateral nucleus accumbens and putamen showed significant negative correlations with number of obstetric complications in the AN group.

DISCUSSION

This study supports the hypothesis that AN is associated with structural and functional alterations of striatal networks, and reveals the possible role of obstetric complications in the pathogenesis of striatal dysfunction.

Combined Influences of Genes, Prenatal Environment, Cortisol, and Parenting on the Development of Children's Internalizing Versus Externalizing Problems

Research suggests that genetic, prenatal, endocrine, and parenting influences across development individually contribute to internalizing and externalizing problems in children. The present study tests the combined contributions of genetic risk for psychopathology, prenatal environments (maternal drug use and internalizing symptoms), child cortisol at age 4.5 years, and overreactive parenting influences across childhood on 6-year-old children's internalizing and externalizing problems. We used data from an adoption design that included 361 domestically adopted children and their biological and adopted parents prospectively followed from birth. Only parenting influences contributed (independently) to externalizing problems. However, genetic influences were indirectly associated with internalizing problems (through increased prenatal risk and subsequent morning cortisol), and parenting factors were both directly and indirectly associated with internalizing problems (through morning cortisol). Results suggest that prenatal maternal drug use/symptoms and children's morning cortisol levels are mechanisms of genetic and environmental influences on internalizing problems, but not externalizing problems, in childhood.

Child-evoked maternal negativity from 9 to 27 months: Evidence of gene-environment correlation and its moderation by marital distress

Past research has documented pervasive genetic influences on emotional and behavioral disturbance across the life span and on liability to adult psychiatric disorder. Increasingly, interest is turning to mechanisms of gene-environment interplay in attempting to understand the earliest manifestations of genetic risk. We report findings from a prospective adoption study, which aimed to test the role of evocative gene-environment correlation in early development. Included in the study were 561 infants adopted at birth and studied between 9 and 27 months, along with their adoptive parents and birth mothers. Birth mother psychiatric diagnoses and symptoms scales were used as indicators of genetic influence, and multiple self-report measures were used to index adoptive mother parental negativity. We hypothesized that birth mother psychopathology would be associated with greater adoptive parent negativity and that such evocative effects would be amplified under conditions of high adoptive family adversity. The findings suggested that genetic factors associated with birth mother externalizing psychopathology may evoke negative reactions in adoptive mothers in the first year of life, but only when the adoptive family environment is characterized by marital problems. Maternal negativity mediated the effects of genetic risk on child adjustment at 27 months. The results underscore the importance of genetically influenced evocative processes in early development.

Pre- and perinatal hypoxia associated with hippocampus/amygdala volume in bipolar disorder

BACKGROUND

Pre- and perinatal adversities may increase the risk for schizophrenia and bipolar disorder. Hypoxia-related obstetric complications (OCs) are associated with brain anatomical abnormalities in schizophrenia, but their association with brain anatomy variation in bipolar disorder is unknown.

METHOD

Magnetic resonance imaging brain scans, clinical examinations and data from the Medical Birth Registry of Norway were obtained for 219 adults, including 79 patients with a DSM-IV diagnosis of bipolar disorder (age 29.4 years, s.d. = 11.8 years, 39% male) and 140 healthy controls (age 30.8 years, s.d. = 12.0 years, 53% male). Severe hypoxia-related OCs throughout pregnancy/birth and perinatal asphyxia were each studied in relation to a priori selected brain volumes (hippocampus, lateral ventricles and amygdala, obtained with FreeSurfer), using linear regression models covarying for age, sex, medication use and intracranial volume. Multiple comparison adjustment was applied.

RESULTS

Perinatal asphyxia was associated with smaller left amygdala volume (t = -2.59, p = 0.012) in bipolar disorder patients, but not in healthy controls. Patients with psychotic bipolar disorder showed distinct associations between perinatal asphyxia and smaller left amygdala volume (t = -2.69, p = 0.010), whereas patients with non-psychotic bipolar disorder showed smaller right hippocampal volumes related to both perinatal asphyxia (t = -2.60, p = 0.015) and severe OCs (t = -3.25, p = 0.003). No associations between asphyxia or severe OCs and the lateral ventricles were found.

CONCLUSIONS

Pre- and perinatal hypoxia-related OCs are related to brain morphometry in bipolar disorder in adulthood, with specific patterns in patients with psychotic versus non-psychotic illness.

Stress system development from age 4.5 to 6: family environment predictors and adjustment implications of HPA activity stability versus change

This study addressed early calibration of stress systems by testing links between adversity exposures, developmental stability of hypothalamic-pituitary-adrenal (HPA) axis activity, and behavior problems in a sample of adopted children. Families (n=200) were assessed when the child was 9, 18, and 27 months, 4.5 and 6 years to collect adversity information-parent psychopathology, stress, financial need, and home chaos. Morning and evening cortisol samples at the final two assessments indexed child HPA activity, and parent-reported internalizing and externalizing at the final assessment represented child behavior outcomes. Increases in cumulative adversity from 4.5 to 6 related to higher child morning cortisol, whereas age six cumulative adversities related to lower, unstable child evening cortisol. Examination of specific adversity dimensions revealed associations between (1) increasing home chaos and stable morning cortisol, which in turn related to internalizing problems; and (2) high parental stress and psychopathology and lower, unstable evening cortisol, which in turn related to externalizing problems.

Disentangling the effects of genetic, prenatal and parenting influences on children's cortisol variability

Developmental plasticity models hypothesize the role of genetic and prenatal environmental influences on the development of the hypothalamic-pituitary-adrenal (HPA) axis and highlight that genes and the prenatal environment may moderate early postnatal environmental influences on HPA functioning. This article examines the interplay of genetic, prenatal and parenting influences across the first 4.5 years of life on a novel index of children's cortisol variability. Repeated measures data were obtained from 134 adoption-linked families, adopted children and both their adoptive parents and birth mothers, who participated in a longitudinal, prospective US domestic adoption study. Genetic and prenatal influences moderated associations between inconsistency in overreactive parenting from child age 9 months to 4.5 years and children's cortisol variability at 4.5 years differently for mothers and fathers. Among children whose birth mothers had high morning cortisol, adoptive fathers' inconsistent overreactive parenting predicted higher cortisol variability, whereas among children with low birth mother morning cortisol adoptive fathers' inconsistent overreactive parenting predicted lower cortisol variability. Among children who experienced high levels of prenatal risk, adoptive mothers' inconsistent overreactive parenting predicted lower cortisol variability and adoptive fathers' inconsistent overreactive parenting predicted higher cortisol variability, whereas among children who experienced low levels of prenatal risk there were no associations between inconsistent overreactive parenting and children's cortisol variability. Findings supported developmental plasticity models and uncovered novel developmental, gene × environment and prenatal × environment influences on children's cortisol functioning.

Prenatal ultrasound exposure and association with postnatal hearing outcomes

Objective

Prenatal ultrasound exams have become increasingly frequent. Although no serious adverse effects are known, the public health implications would be enormous should adverse effects on auditory development be shown. This study looks to establish a possible correlation between hearing loss and increased prenatal ultrasound exposure.

Design

Retrospective cohort analysis.

Setting

Tertiary academic referral center.

Methods

A retrospective review of 100 children undergoing newborn hearing screening was conducted. Extensive data collection was performed, and this data was analyzed for a potential correlation between failure of newborn hearing screening and increased prenatal ultrasound exposure, as well as for a potential correlation of other variables with hearing loss.

Main outcome measures

Postnatal hearing outcomes.

Results

A higher number of both total and 3^rd trimester ultrasound exams as well as a younger gestational age at birth were all found to be significantly associated with a higher likelihood of passing the newborn hearing screen (p<0.001 for each). No other factors were found to reach statistical significance.

Conclusions

Our results show that there is no correlation between a higher level of prenatal ultrasound exposure and hearing loss. Indeed, infants who had more prenatal ultrasounds in the third trimester were more likely to pass their screening hearing exams. The finding that children receiving more prenatal ultrasounds have a higher likelihood of passing newborn hearing screens serves as an excellent reminder of the classic statistics rule that correlation does not imply causation.

Obstetric complications in early psychosis: relation with family history of psychosis

The people classified as being at ultra-high risk (UHR) of developing psychosis are expected to share many risk factors for psychosis with the patients diagnosed with schizophrenia, including an enhanced incidence of obstetric complications (OCs). This study set out to investigate the incidence and correlates of OCs in a sample of patients accessing an early intervention center. Patients' mothers were asked whether they had suffered from any somatic complication during pregnancy from a list of OCs with potential direct relevance to the physical wellbeing of the offspring. Out of 86 patients diagnosed with first-episode psychosis, 20 (23%) cases were positive for the occurrence of severe OCs, as reported by their mothers during an interview; out of 83 UHR patients, 21 (25%) cases were positive for OCs. OCs were more common in individuals with a family history of psychosis than in those without such a history. OCs might interact with genetic vulnerability to increase the risk of psychosis. Lack of comparison to healthy controls is a limitation that decreases the value of these findings.

LPHN3 and attention-deficit/hyperactivity disorder: interaction with maternal stress during pregnancy

BACKGROUND

Attention-deficit/hyperactivity disorder (ADHD) is a heterogeneous behavioral disorder, complex both in etiology and clinical expression. Both genetic and environmental factors have been implicated, and it has been suggested that gene-environment interactions may play a pivotal role in the disorder. Recently, a significant association was reported between ADHD and LPHN3 (which codes for latrophilin 3), and replicated in independent samples.

METHODS

We have examined the association between tag single nucleotide polymorphisms (SNPs) in LPHN3 within the region previously implicated in ADHD. Family based association tests (FBAT) were conducted (n = 380 families) with the categorical diagnosis of ADHD, behavioral and cognitive phenotypes related to ADHD, and response to treatment (given a fixed dose of methylphenidate, 0.5 mg/day). Stratified FBAT analyses, based on maternal smoking and stress during pregnancy, was conducted.

RESULTS

Whereas limited association was observed in the total sample, highly significant interaction between four LPHN3 tag SNPs (rs6551665, rs1947274, rs6858066, rs2345039) and maternal stress during pregnancy was noted. Analysis conducted in the sub-group of mothers exposed to minimal stress during pregnancy showed significant associations with ADHD, behavioral and cognitive dimensions related to ADHD, as well as treatment response. Although extensive association was observed with the candidate SNPs, the findings are partially inconsistent with previously published results with the opposite alleles over-transmitted in these studies.

CONCLUSIONS

These results provide evidence for the interaction between a genetic and environmental factor independently shown to be associated with ADHD. If confirmed in independent large studies, they may present a step forward in unraveling the complex etiology of ADHD.

Cortical folding in Broca's area relates to obstetric complications in schizophrenia patients and healthy controls

BACKGROUND

The increased occurrence of obstetric complications (OCs) in patients with schizophrenia suggests that alterations in neurodevelopment may be of importance to the aetiology of the illness. Abnormal cortical folding may reflect subtle deviation from normal neurodevelopment during the foetal or neonatal period. In the present study, we hypothesized that OCs would be related to cortical folding abnormalities in schizophrenia patients corresponding to areas where patients with schizophrenia display altered cortical folding when compared with healthy controls.

METHOD

In total, 54 schizophrenia patients and 54 healthy control subjects underwent clinical examination and magnetic resonance image scanning on a 1.5 T scanner. Information on OCs was collected from original birth records. An automated algorithm was used to calculate a three-dimensional local gyrification index (lGI) at numerous points across the cortical mantle.

RESULTS

In both schizophrenia patients and healthy controls, an increasing number of OCs was significantly related to lower lGI in the left pars triangularis (p<0.0005) in Broca's area. For five other anatomical cortical parcellations in the left hemisphere, a similar trend was demonstrated. No significant relationships between OCs and lGI were found in the right hemisphere and there were no significant case-control differences in lGI.

CONCLUSIONS

The reduced cortical folding in the left pars triangularis, associated with OCs in both patients and control subjects suggests that the cortical effect of OCs is caused by factors shared by schizophrenia patients and healthy controls rather than factors related to schizophrenia alone.

Maternal smoking during pregnancy and ADHD: a comprehensive clinical and neurocognitive characterization

INTRODUCTION

Evidence from epidemiological studies has consistently shown an association between maternal smoking during pregnancy (MSDP) and attention-deficit/hyperactivity disorder (ADHD). The objective of this study is to test the hypothesis that children with ADHD exposed to MSDP show a distinctive clinical and neurocognitive profile when compared with unexposed children.

METHODS

Four hundred and thirty-six children diagnosed with ADHD were stratified by exposure to MSDP and compared with regard to severity of illness, comorbidity, IQ, and executive function as assessed by a battery of neuropsychological tests. All comparisons were adjusted for socioeconomic status, ethnicity, mother's age at child's birth, and maternal alcohol consumption during pregnancy.

RESULTS

Exposed children had more severe behavioral problems with greater externalizing symptoms and more conduct and oppositional defiant disorder items, lower verbal IQ, and a sluggish cognitive profile on the Continuous Performance Test (CPT). Linear regression analyses revealed a dose-response relationship between the average number of cigarettes smoked per day during pregnancy and verbal IQ, CPT omission errors T score and several other clinical variables.

CONCLUSIONS

These results suggest that MSDP is associated with a more severe form of ADHD, characterized by more severe clinical manifestations and poorer neuropsychological performance. This phenotypic signature associated with MSDP may help to identify a more homogenous subgroup of children with ADHD.

Obstetric Events as a Risk Factor for Febrile Seizures: A Community-Based Twin Study

Adverse events during the perinatal period have traditionally been thought to contribute to the risk of febrile seizures although an association has not been found in large epidemiological studies. Disease-discordant twins provide a means to assess the role of non-shared environmental factors while matching for confounding factors and avoiding difficulties of epidemiological studies in singletons. This study aimed to examine the association of obstetric events and febrile seizures in a community-based twin study. Twenty-one twin pairs discordant for febrile seizures were ascertained from a community-based twin register. Obstetric events were scored using the McNeil-Sjöström Scale for Obstetric Complications and expressed as a summary score (OC score). The frequency of individual obstetric events in affected and unaffected twins, the within-pair differences in OC scores and other markers of perinatal risk including birthweight, birth order and Apgar scores were examined. No significant difference was found in the frequency of individual obstetric events, nor in OC scores between affected and unaffected twins. No differences in birth weight, birth order, 1- or 5-minute Apgar scores were observed. Our results confirm previous findings that obstetric events are not associated with the risk of febrile seizures.

Perinatal complications in unaffected sisters of anorexia nervosa patients: testing a covariation model between genetic and environmental factors

Although perinatal complications are hypothesized to be risk factors for the development of anorexia nervosa (AN), no study to date explored this issue using a discordant sibling design. This type of design allows to explore whether the risk for obstetric complications is itself a consequence of the genetic vulnerability for AN (covariation model) or whether obstetric complications increase the risk of AN independently of (additive model), or in interaction with (interaction model), the disorder's genetic liability. The presence of perinatal complications was assessed through review of the obstetric records of 60 AN subjects, 60 unaffected sisters, and 70 healthy subjects. Unaffected sisters and healthy controls were compared in relation to perinatal characteristics and complications. There was no evidence for an elevated rate of complications in unaffected siblings of AN patients. Mothers with a positive psychiatric history tended to have more perinatal complications. Perinatal complications seem to be independent risk factors that may interact with, but are not caused by, familial risk factors for AN. In terms of prevention, a particular attention should be paid to mothers with a lifetime history of psychiatric disorders.

Long-term maternal recall of obstetric complications in schizophrenia research

Obstetric complications (OCs) are consistently implicated in the aetiology of schizophrenia. Information about OCs is often gathered retrospectively, from maternal interview. It has been suggested that mothers of people with schizophrenia may not be accurate in their recollection of obstetric events. We assessed the validity of long term maternal recall by comparing maternal ratings of OCs with those obtained from medical records in a sample of mothers of offspring affected and unaffected with psychotic illness. Obstetric records were retrieved for 30 subjects affected with psychosis and 40 of their unaffected relatives. The Lewis-Murray scale of OCs was completed by maternal interview for each subject blind to the obstetric records. There was substantial agreement between maternal recall and birth records for the summary score of "definite" OCs, birth weight, and most of the individual items rated, with the exception of antepartum haemorrhage. There were no significant differences in the validity of recall or in errors of commission by mothers for affected and unaffected offspring. These findings indicate that several complications of pregnancy and delivery are accurately recalled by mother's decades after they occurred. Furthermore, there is no indication that mothers are less accurate in recalling OCs for their affected offspring than their unaffected offspring. When comparing women with and without recall errors, we found those with recall errors to have significantly worse verbal memory than women without such errors. Assessing the cognition of participants in retrospective studies may allow future studies to increase the reliability of their data.

Recorded pregnancy histories of the mothers of singletons and the mothers of twins: a longitudinal comparison

A population-based record linkage case cohort of 239,995 births, to 119,214 women, born in Western Australia from 1980 to 2001 inclusive, was used to measure the recording of selected indicators of maternal health (current and prior) during pregnancy. We compared records of women with singleton pregnancies with that in twin pregnancies Mothers of first- and second-born singletons (n = 117,647) were compared with women with a first-born singleton followed by twins (n = 1,567). Binary indicators were used to calculate population prevalence of medical conditions, pregnancy complications and birth outcomes. Infant outcomes included stillbirth, low birthweight, preterm birth and birth defects. Women with twins were significantly older and taller, with similar rates of medical conditions and pregnancy complications during first singleton pregnancies compared with women with two consecutive singletons. However, during their second pregnancy, women with twins had significantly higher rates of essential hypertension, pre-eclampsia, threatened abortion, premature rupture of the membranes and ante partum hemorrhage with abruption than women with singletons. For both groups, maternal conditions in the first pregnancy were underreported in the second pregnancy, including diabetes, epilepsy, asthma, chronic renal dysfunction and essential hypertension. At the second birth, twins were 3 times more likely to be stillborn, 17 times more likely to be low birthweight and 4 times more likely to be delivered preterm compared with singletons. This research demonstrates the importance for epidemiologists and others, of having access to a complete maternal medical history for analyses of risks associated with maternal, infant and childhood morbidity.

Influence of parental depressive symptoms on adopted toddler behaviors: an emerging developmental cascade of genetic and environmental effects

This study examined the developmental cascade of both genetic and environmental influences on toddlers' behavior problems through the longitudinal and multigenerational assessment of psychosocial risk. We used data from the Early Growth and Development Study, a prospective adoption study, to test the intergenerational transmission of risk through the assessment of adoptive mother, adoptive father, and biological parent depressive symptoms on toddler behavior problems. Given that depression is often chronic, we control for across-time continuity and find that in addition to associations between adoptive mother depressive symptoms and toddler externalizing problems, adoptive father depressive symptoms when the child is 9 months of age were associated with toddler problems and associated with maternal depressive symptoms. Findings also indicated that a genetic effect may indirectly influence toddler problems through prenatal pregnancy risk. These findings help to describe how multiple generations are linked through genetic (biological parent), timing (developmental age of the child), and contextual (marital partner) pathways.

Understanding the genesis of psychotic disorder: Issues in the prediction and prophylaxis of those at ultra-high risk

PURPOSE

Recent research is starting to identify individuals at an increased risk of developing a psychotic disorder. This review seeks to identify the 'state of the art' with respect to the clinical identification and treatment of individuals at 'ultra-high risk'.

METHOD

The research and clinical literature are reviewed with respect to a wide range of predictors relevant across development.

RESULTS

The review draws on evidence from childhood and adolescence to suggest that a range of biological, cognitive, personality, and social features are predictive of, but often not specific to, psychosis within the context of the diathesis-stress model. Much evidence supports the view that environmental stressors act in combination with vulnerability factors to increase risk of transition, often during late adolescence and early adulthood.

CONCLUSIONS

Recent clinical research has used both retrospective and prospective means of identifying individuals at ultra-high risk and has made substantial gains in predicting transition. The clinical implications of their identification are discussed in the context of current pharmacological and psychosocial treatment studies. However, significant unresolved clinical and ethical issues remain with both types of study.

Correlations between obstetric complications and neurological soft signs in Tunisian patients with schizophrenia

The objective of this study was to examine the correlations between a history of obstetric complications (OC) and neurological soft signs (NSS) in Tunisian patients with schizophrenia. Forty-six patients were assessed using the Krebs et al. NSS scale. History of OC was obtained from the patients' mothers using the McNeil–Sjöström scale. Although there was no significant difference in NSS between patients with and without OC, there were negative correlations between OC total score and motor coordination and integration sub-scores. These negative correlations suggest that OC could enhance the effects of genetic risk factors for schizophrenia.

An exploratory model for G x E interaction on hippocampal volume in schizophrenia; obstetric complications and hypoxia-related genes

BACKGROUND

Smaller hippocampal volume has repeatedly been reported in schizophrenia patients. Obstetric complications (OCs) and single nucleotide polymorphism (SNP) variation in schizophrenia susceptibility genes have independently been related to hippocampal volume. We investigated putative independent and interaction effects of severe hypoxia-related OCs and variation in four hypoxia-regulated schizophrenia susceptibility genes (BDNF, DTNBP1, GRM3 and NRG1) on hippocampal volume in schizophrenia patients and healthy controls.

METHODS

Clinical assessment, structural MRI scans, and blood samples for genotyping of 32 SNPs were obtained from 54 schizophrenia patients and 53 control subjects. Information on obstetric complications was collected from original birth records.

RESULTS

Severe OCs were related to hippocampal volume in both patients with schizophrenia and healthy control subjects. Of the 32 SNPs studied, effects of severe OCs on hippocampal volume were associated with allele variation in GRM3 rs13242038, but the interaction effect was not specific for schizophrenia. SNP variation in any of the four investigated genes alone did not significantly affect hippocampal volume.

CONCLUSIONS

The findings suggest a gene-environment (G x E) interaction between GRM3 gene variants and severe obstetric complications on hippocampus volume, independent of a diagnosis of schizophrenia. Due to the modest sample size, the results must be considered preliminary and require replication in independent samples.

Prenatal risk factors and schizophrenia

This article highlights major research findings that indicate a relation between prenatal environmental factors and the risk of adult schizophrenia. Evidence suggests that schizophrenia may have its origins in early maldevelopment of the brain. However, the factors responsible for this devastating disorder remain unknown. While genes clearly play a causal role, there is likely an environmental contribution as well. We discuss the evidence for several candidate environmental exposures that occur during prenatal life and that may modify the risk for developing schizophrenia. The main challenge of this type of research, termed risk-factor epidemiology, is to generate and test such exposures in subjects with schizophrenia, in order to develop preventive strategies and better understand the mechanisms that lead to this illness.

No effect of obstetric complications on basal ganglia volumes in schizophrenia

BACKGROUND

Heterogeneous findings have been reported in studies of basal ganglia volumes in schizophrenia patients as compared to healthy controls. The basal ganglia contain dopamine receptors that are known to be involved in schizophrenia pathology and to be vulnerable to pre- and perinatal hypoxic insults. Altered volumes of other brain structures (e.g. hippocampus and lateral ventricles) have been reported in schizophrenia patients with a history of obstetric complications (OCs). This is the first study to explore if there is a relationship between OCs and basal ganglia volume in schizophrenia.

METHODS

Thorough clinical investigation (including information on medication) of 54 schizophrenia patients and 54 healthy control subjects was undertaken. MR images were obtained on a 1.5T scanner, and volumes of nucleus caudatus, globus pallidum, putamen, and nucleus accumbens were quantified automatically. Information on OCs was blindly collected from original birth records.

RESULTS

Unadjusted estimates demonstrated a relationship between increasing number of OCs and larger volume of nucleus accumbens in schizophrenia patients and healthy controls. No statistically significant relationships were found between OCs and the basal ganglia volumes when controlled for intracranial volume, age, and multiple comparisons. There were no effects of typical versus atypical medication on the basal ganglia volumes. The patients with schizophrenia had larger globus pallidum volumes as compared to healthy controls, but there were no case-control differences for accumbens, putamen, or caudate volumes.

CONCLUSION

The present results do not support the hypothesis that OCs are related to alterations in basal ganglia volume in chronic schizophrenia.