Disruptive behaviour disorders: a systematic review of environmental antenatal and early years risk factors

Occupational exposure to organic solvents during pregnancy and child behavior from early childhood to adolescence

BACKGROUND

Organic solvents are used in formulating an extensive range of products for professional use. Animal and human studies suggest that in utero solvent exposure may affect neurodevelopment. Our objective was to assess the association between occupational exposure to solvents during pregnancy and child behavior aged 2-12 years.

METHODS

The French mother-child cohort PELAGIE (2002-2006) included 3,421 women recruited in early pregnancy. Occupational exposure to solvents was self-reported. For 459 children, parents used a questionnaire derived from the Child Behavior Checklist and the Preschool Social Behavior Questionnaire to assess their child's behavior, at age 2, and the Strengths and Difficulties Questionnaire at ages 6 and 12. A cross-lagged structural equation modeling approach was used to assess direct and indirect associations between exposure and child behavior.

RESULTS

At age 2, an increased externalizing behavior score was suggested with prenatal exposure to solvents (mean change in standardized score (95%CI): 0.28 (-0.01, 0.57) for occasional exposure and 0.23 (-0.05, 0.51) for regular exposure). At ages 6 and 12, distinct sex-specific patterns were observed: among boys, no association with externalizing behavior was observed, while among girls, an association was seen for both occasional and regular exposure (total effect at age 12: 0.45 (0.06,0.83) and 0.40 (0.03, 0.76), respectively). For both sexes, occasional exposure may be associated with internalizing behavior at ages 6 and 12 (total effect at age 6: 0.37 (0.06, 0.68) and at age 12: 0.27 (-0.08, 0.62)).

CONCLUSIONS

Occupational exposure to solvents during pregnancy may impact child behavior through either direct or cumulative effects during childhood; these associations may persist until early adolescence, especially among girls.

Prenatal Tobacco Exposure and Behavioral Disorders in Children and Adolescents: Systematic Review and Meta-Analysis

Prenatal tobacco exposure has been implicated in increased risk of the development of behavioral disorders in children and adolescents. The purpose of the current study was to systematically examine the association between prenatal tobacco exposure and diagnoses of Attention Deficit/Hyperactivity Disorder, Oppositional Defiant Disorder, and Conduct Disorder in childhood and adolescence. We searched Medline, Psychinfo, ERIC, Proquest, Academic Search Complete, PsychArticles, Psychology and Behavioral Sciences Collection, Web of Science, CINAHL Plus, and Google Scholar databases through October 2022. The authors screened studies and extracted data independently in duplicate. Ten clinical studies examining diagnoses of Attention Deficit/Hyperactivity Disorder, Oppositional Defiant Disorder, and Conduct Disorder between the ages of 4 and 18 years old were included. There was insufficient evidence to synthesize outcomes related to Conduct Disorder and Oppositional Defiant Disorder. The meta-analysis found a significant effect of prenatal tobacco exposure in increasing the likelihood of an Attention Deficit/Hyperactivity Disorder diagnosis in childhood and adolescence. Implications for future research are discussed.

Are Children Following High Trajectories of Disruptive Behaviors in Early Childhood More or Less Likely to Follow Concurrent High Trajectories of Internalizing Problems?

The developmental association between disruptive behaviors (DBs: hyperactivity-impulsivity, non-compliance, physical aggression) and internalizing problems in early childhood is not well understood and has generated competing hypotheses and mixed results. Using a person-centered strategy, the present study aimed to examine concurrent trajectories of DBs and trajectories of internalizing problems from age 1.5 to 5 years in a population-representative sample (N = 2057; 50.7% boys). Six trajectories of DBs and three trajectories of internalizing problems, based on parent reports and obtained via latent growth modeling across five periods of assessment, were used as longitudinal indicators of each type of behaviors. Children following low or moderate trajectories served as the reference class. Compared to children in the reference class, those in trajectory classes characterized by high levels of co-occurring DBs (OR = 6.60) and, to a lesser extent, those in single high DB classes (OR = 2.78) were more likely to follow a high trajectory of internalizing problems simultaneously. These results support a multiple problem hypothesis regarding the association between DBs and internalizing problems, consistent with a developmental perspective that includes a general factor underpinning different psychopathologies. These findings highlight the importance of considering the co-occurrence between DBs and internalizing problems when studying either construct in children.

The developmental origins of suicide mortality: a systematic review of longitudinal studies

Suicide prevention efforts generally target acute precipitants of suicide, though accumulating evidence suggests that vulnerability to suicide is partly established early in life before acute precipitants can be identified. The aim of this systematic review was to synthesize evidence on early life vulnerability to suicide beginning in the prenatal period and extending through age 12. We searched PubMed, Embase, PsycNet, Web of Science, Scopus, Social Services Abstracts, and Sociological Abstracts for prospective studies published through January 2021 that investigated early life risk factors for suicide mortality. The search yielded 13,237 studies; 54 of these studies met our inclusion criteria. Evidence consistently supported the link between sociodemographic (e.g., young maternal age at birth, low parental education, and higher birth order), obstetric (e.g., low birth weight), parental (e.g., exposure to parental death by external causes), and child developmental factors (e.g., exposure to emotional adversity) and higher risk of suicide death. Among studies that also examined suicide attempt, there was a similar profile of risk factors. We discuss a range of potential pathways implicated in these associations and suggest that additional research be conducted to better understand how early life factors could interact with acute precipitants and increase vulnerability to suicide.

Pre- and Perinatal Risk Factors for Youth with Autism Spectrum Disorder Versus Youth with Other Mental Health Disorders

Research has linked pre- and perinatal complications (PPCs) with increased risk for autism spectrum disorder (ASD). However, PPCs are also known risk factors for other mental health disorders. This study explored which PPCs are specific risk factors for ASD, as opposed to other forms of psychopathology, among a large sample of clinically-referred youth. Archival data were used from 1177 youth who were evaluated at a hospital-based autism clinic. Results from logistic regressions indicated that use of tobacco, alcohol, or drugs, or experiencing amniocentesis predicted inclusion in the non-ASD group, while physical difficulties with delivery predicted inclusion in the ASD group. Possible explanations and implications for these findings are discussed.

Psychiatric disorders in term-born children with marginally low birth weight: a population-based study

BACKGROUND

Marginally low birth weight (MLBW) is defined as a birth weight of 2000 ~ 2499 g. Inconsistent findings have been reported on whether children with low birth weight had higher rates of neurological, attention, or cognitive symptoms. No studies have explored the occurrence of clinically diagnosed psychiatric disorders in term- born MLBW infants. We aimed to investigate the risk of subsequent psychiatric disorders in term-born children with MLBW.

METHODS

This is a nationwide retrospective cohort study, by analysing the data from Taiwan's National Health Insurance Research Database from 2008 to 2018. The study population includes propensity-score-matched term-born infants with MLBW and those without MLBW (birth weight ≥ 2500 g). Cox proportional hazard analysis was used after adjustment for potential demographic and perinatal comorbidity confounders. Incidence rates and hazard ratios (HR) of 11 psychiatric clinical diagnoses were evaluated.

RESULTS

A total of 53,276 term-born MLBW infants and 1,323,930 term-born infants without MLBW were included in the study. After propensity score matching for demographic variables and perinatal comorbidities, we determined that the term-born MLBW infants (n = 50,060) were more likely to have attention deficit and hyperactivity disorder (HR = 1.26, 95% confidence interval (CI) [1.20, 1.33]), autism spectrum disorder (HR = 1.26, 95% CI [1.14, 1.40]), conduct disorder (HR = 1.25, 95% CI [1.03, 1.51]), emotional disturbance (HR: = 1.13, 95% CI [1.02, 1.26]), or specific developmental delays (HR = 1.38, 95% CI [1.33, 1.43]) than term-born infants without MLBW (n = 50,060).

CONCLUSION

MLBW was significantly associated with the risk of subsequent psychiatric disorder development among term-born infants. The study findings demonstrate that further attention to mental health and neurodevelopment issues may be necessary in term-born children with MLBW. However, possibilities of misclassification in exposures or outcomes, and risks of residual and unmeasured confounding should be concerned when interpreting our data.

Prenatal Exposure to Perfluoroalkyl Substances and Child Behavior at Age 12: A PELAGIE Mother-Child Cohort Study

BACKGROUND

Per- and polyfluoroalkyl substances (PFAS) are chemical substances spread throughout the environment worldwide. Exposure during pregnancy represents a specific window of vulnerability for child health.

OBJECTIVE

Our objective was to assess the impact of prenatal exposure to multiple PFAS on emotional and behavioral functions in 12-y-old children.

METHOD

In the PELAGIE mother-child cohort (France), prenatal exposure to nine PFAS was measured from concentrations in cord serum samples. Behavior was assessed at age 12 y using the parent-reported Strengths and Difficulties Questionnaire (SDQ) and the self-reported Dominic Interactive for Adolescents (DIA) for 444 children. Associations were estimated using negative binomial models for each PFAS. Bayesian kernel machine regression (BKMR) models were performed to assess the exposure mixture effect on children's behavior.

RESULTS

In our study population, 73% of mothers had spent more than 12 y in education. Higher scores on SDQ externalizing subscale were observed with increasing cord-serum concentration of perfluorooctanoic acid (PFOA) and perfluorononanoic acid (PFNA) [adjusted mean ratio ( aMR ) = 1.18 , 95% confidence interval (CI): 1.03, 1.34, and aMR = 1.14 (95% CI: 1.00, 1.29) for every doubling of concentration, respectively]. Results for the hyperactivity score were similar [aMR = 1.20 (95% CI: 1.04, 1.40) and aMR = 1.18 (95% CI: 1.02, 1.36), respectively]. With regard to major depressive disorder and internalizing subscales, perfluorodecanoic acid (PFDA) was associated with higher self-reported DIA scores [aMR = 1.14 (95% CI: 1.01, 1.27) and aMR = 1.11 (95% CI: 1.02, 1.21), respectively]. In terms of the anxiety subscale, PFDA and PFNA were associated with higher scores [aMR = 1.11 (95% CI: 1.02, 1.21) and aMR = 1.10 (95% CI: 1.01, 1.19), respectively]. Concurrent increases in the PFAS concentrations included in the BKMR models showed no change in the SDQ externalizing and DIA internalizing subscales scores.

CONCLUSION

Prenatal exposure to PFNA and PFOA were associated with increasing scores for measures of externalizing behaviors, specifically hyperactivity. We also identified associations between PFNA and PFDA prenatal exposure levels and increasing scores related to internalizing behaviors (general anxiety and major depressive disorder), which adds to the as yet sparse literature examining the links between prenatal exposure to PFAS and internalizing disorders. https://doi.org/10.1289/EHP12540.

Conditions of Birth and Early Childhood Developmental Risk for Mental Disorders

Distinct classes of children in the general population are at increased odds of later mental illness and other adverse outcomes according to patterns of early childhood developmental vulnerability. If certain risk factors known at the time of birth are reliably associated with membership in early childhood risk classes, then preventative interventions could be initiated in the earliest years of life. Associations between 14 factors known at the time of birth and membership in early childhood risk classes were examined in 66,464 children. Risk class membership was associated with maternal mental illness, parental criminal charges and being male; distinct patterns of association were shown for some conditions, for example, prenatal child protection notification was uniquely associated with misconduct risk'. These findings suggest that risk factors known at the time of birth could assist in very early detection of children who may benefit from early intervention in the first 2000 days.

The computational psychiatry of antisocial behaviour and psychopathy

Antisocial behaviours such as disobedience, lying, stealing, destruction of property, and aggression towards others are common to multiple disorders of childhood and adulthood, including conduct disorder, oppositional defiant disorder, psychopathy, and antisocial personality disorder. These disorders have a significant negative impact for individuals and for society, but whether they represent clinically different phenomena, or simply different approaches to diagnosing the same underlying psychopathology is highly debated. Computational psychiatry, with its dual focus on identifying different classes of disorder and health (data-driven) and latent cognitive and neurobiological mechanisms (theory-driven), is well placed to address these questions. The elucidation of mechanisms that might characterise latent processes across different disorders of antisocial behaviour can also provide important advances. In this review, we critically discuss the contribution of computational research to our understanding of various antisocial behaviour disorders, and highlight suggestions for how computational psychiatry can address important clinical and scientific questions about these disorders in the future.

Systematic Review of Environmental and Psychosocial Risk Factors associated with Attention Deficit Hyperactivity Disorder, Oppositional Defiant Disorder, and Conduct Disorder in Children and Adolescents

Background

In the majority of cases, attention deficit hyperactivity disorder (ADHD) is accompanied by one or more comorbid disorders, with the oppositional defiant disorder (ODD) being one of the most frequently diagnosed comorbid disorders. There is a lack of systematic reviews addressing the evidence for an association between the independent environmental and psychosocial risk factors associated with ADHD, ODD, and Conduct Disorder (CD).

Objective

This study aims to determine the link between ADHD and ODD/CD, specifically in terms of the most up-to-date environmental and psychosocial risk factors in the development of these illnesses.

Results

Eleven studies were included in this systematic review. Among these, ten studies involved environmental risk factors, and only one involved socioeconomic risk factors as exposure. Of the ten studies highlighting the environmental risk factors, six studies reported perinatal risk factors, three reported Atopic diseases as exposure measures, and one involved exposure to energy and coffee drinks. We have found that the most common risk factors associated with ADHD, ODD and CD in Europe and North America were Perinatal risk factors. In contrast, the risk factors of Atopic diseases were more common in Asia.

Conclusions

Most of the studies included in our systematic review fall within the scope of environmental risk factors were perinatal risk factors and atopic diseases are the most common risk factors. However, only one article highlighted the association of socioeconomic risk factors as an exposure. Our review results suggest the need for more research focused on psychosocial risk factors for ADHD and comorbid ODD/CD. Further research is required with the primary objective of investigating this association in greater depth and examining the possible mechanisms at varying levels is needed.

Family interactions in toddlerhood influence social competence in preschool age: Accounting for genetic and prenatal influences

Identification of early promotive and risk factors for social competence is important for fostering children's successful social development; particularly given social competence is essential for children's later academic and psychological well-being. While research suggests that the early parent-child relationship, genetics, and prenatal influences are associated with social competence, there is less research considering how these factors may operate together to shape children's social competence in early childhood. Using a genetically informed sample from the Early Growth and Development Study (N = 561), we examined multiple levels of influence (i.e., genetic, prenatal, parenting, and child characteristics) on children's social competence at 4.5 years old. Results from structural equation models showed adoptive mother overreactivity at 18 months was positively associated with child dysregulation at 27 months, which, in turn, was associated with lower levels of social competence at 4.5 years. Also, child reactivity at 18 months was independently associated with higher levels of adoptive mother overreactivity at 27 months, which, in turn, was associated with lower levels of social competence at 4.5 years. Finally, we found an evocative effect on adoptive fathers' overreactivity at 18 months such that prenatal birth mother distress was negatively associated with adoptive fathers' overreactivity at 18 months. Overall, this study found evidence for genetic influences, and bidirectional associations between parent and child in toddlerhood that are related to lower levels of social competence when children were 4.5 years old. We also found that the prenatal environment was associated with parenting, but not with child behavior directly. This study's ability to simultaneously examine multiple domains of influence helps provide a more comprehensive picture of important mechanisms and developmental periods for children's early social competence.

Is ADHD a way of conceptualizing long-term emotional stress and social disadvantage?

Background

The prevalent, neuropsychiatric, deficit perspective on children and youth diagnosed with ADHD prohibits a multidimensional approach where socio-economic status, family stress and relationships within the families are relevant factors to examine. Assessments of ADHD through the use of rating scales and short-term interventions may lead not only to overdiagnosis but also to a reductionistic approach in the psychiatric field. This literature review aims to address research outside the prevailing discourse on ADHD as an organic brain dysfunction and broaden the perspectives on children's behavioral difficulties.

Methods

The articles included in this applied, mixed-method, systematic review includes 26 peer-reviewed articles, both English and French, with a search focus on ADHD in children and youth related to Attachment styles and relationships.

Results

In the studies reported, researchers approached correlations between ADHD and attachment in different ways, and in most cases, there was a caution to address causality. The role of parents was found to be both buffering and aggravating for the appearance of ADHD. In the French case studies, the diagnosis was conceptualized as a relational phenomenon where the child's behavior was inseparable from family member's suffering.

Discussion

This review article illustrates how children's difficulties in terms of ADHD symptoms can be addressed through a paradigm where emotional and cognitive dysregulation is understood through psychosocial factors rather than as a neurological condition. In our view, to avoid an overly reductionistic and medicalized approach to children's behavioral difficulties, it is time to reiterate the value of the biopsychosocial perspective.

Conclusion

Professionals and researchers need to acknowledge that becoming diagnosed with ADHD has a strong connection to economic disadvantage, social status, and familial care. The academic discourse of addressing brain dysfunctions might serve the unintended purpose of masking emotional stress and social disadvantage that manifests across generations. A biopsychosocial approach to ADHD including family, emotional history, and socio-economic issues could imply a lesser focus on medical treatment as a first choice.

Biological determinants impact the neurovascular toxicity of nicotine and tobacco smoke: A pharmacokinetic and pharmacodynamics perspective

Accumulating evidence suggests that the detrimental effect of nicotine and tobacco smoke on the central nervous system (CNS) is caused by the neurotoxic role of nicotine on blood-brain barrier (BBB) permeability, nicotinic acetylcholine receptor expression, and the dopaminergic system. The ultimate consequence of these nicotine associated neurotoxicities can lead to cerebrovascular dysfunction, altered behavioral outcomes (hyperactivity and cognitive dysfunction) as well as future drug abuse and addiction. The severity of these detrimental effects can be associated with several biological determinants. Sex and age are two important biological determinants which can affect the pharmacokinetics and pharmacodynamics of several systemically available substances, including nicotine. With regard to sex, the availability of gonadal hormone is impacted by the pregnancy status and menstrual cycle resulting in altered metabolism rate of nicotine. Additionally, the observed lower smoking cessation rate in females compared to males is a consequence of differential effects of sex on pharmacokinetics and pharmacodynamics of nicotine. Similarly, age-dependent alterations in the pharmacokinetics and pharmacodynamics of nicotine have also been observed. One such example is related to severe vulnerability of adolescence towards addiction and long-term behavioral changes which may continue through adulthood. Considering the possible neurotoxic effects of nicotine on the central nervous system and the deterministic role of sex as well as age on these neurotoxic effects of smoking, it has become important to consider sex and age to study nicotine induced neurotoxicity and development of treatment strategies for combating possible harmful effects of nicotine. In the future, understanding the role of sex and age on the neurotoxic actions of nicotine can facilitate the individualization and optimization of treatment(s) to mitigate nicotine induced neurotoxicity as well as smoking cessation therapy. Unfortunately, however, no such comprehensive study is available which has considered both the sex- and age-dependent neurotoxicity of nicotine, as of today. Hence, the overreaching goal of this review article is to analyze and summarize the impact of sex and age on pharmacokinetics and pharmacodynamics of nicotine and possible neurotoxic consequences associated with nicotine in order to emphasize the importance of including these biological factors for such studies.

The methylome in females with adolescent Conduct Disorder: Neural pathomechanisms and environmental risk factors

Conduct Disorder (CD) is an impairing psychiatric disorder of childhood and adolescence characterized by aggressive and dissocial behavior. Environmental factors such as maternal smoking during pregnancy, socio-economic status, trauma, or early life stress are associated with CD. Although the number of females with CD is rising in Western societies, CD is under-researched in female cohorts. We aimed at exploring the epigenetic signature of females with CD and its relation to psychosocial and environmental risk factors. We performed HpaII sensitive genome-wide methylation sequencing of 49 CD girls and 50 matched typically developing controls and linear regression models to identify differentially methylated CpG loci (tags) and regions. Significant tags and regions were mapped to the respective genes and tested for enrichment in pathways and brain developmental processes. Finally, epigenetic signatures were tested as mediators for CD-associated risk factors. We identified a 12% increased methylation 5’ of the neurite modulator SLITRK5 (FDR = 0.0046) in cases within a glucocorticoid receptor binding site. Functionally, methylation positively correlated with gene expression in lymphoblastoid cell lines. At systems-level, genes (uncorr. P < 0.01) were associated with development of neurons, neurite outgrowth or neuronal developmental processes. At gene expression level, the associated gene-networks are activated perinatally and during early childhood in neocortical regions, thalamus and striatum, and expressed in amygdala and hippocampus. Specifically, the epigenetic signatures of the gene network activated in the thalamus during early childhood correlated with the effect of parental education on CD status possibly mediating its protective effect. The differential methylation patterns identified in females with CD are likely to affect genes that are expressed in brain regions previously indicated in CD. We provide suggestive evidence that protective effects are likely mediated by epigenetic mechanisms impairing specific brain developmental networks and therefore exerting a long-term effect on neural functions in CD. Our results are exploratory and thus, further replication is needed.

Prenatal origins of suicide mortality: A prospective cohort study in the United States

Most suicide research focuses on acute precipitants and is conducted in high-risk populations. Yet, vulnerability to suicide is likely established years prior to its occurrence. In this study, we aimed to investigate the risk of suicide mortality conferred by prenatal sociodemographic and pregnancy-related factors. Offspring of participants (N = 49,853) of the Collaborative Perinatal Project, a U.S. population-based cohort of pregnancies enrolled between 1959 and 1966, were linked to the U.S. National Death Index to determine their vital status by the end 2016. We examined associations between sociodemographic factors during pregnancy, pregnancy complications, labor and delivery complications, and neonatal complications with suicide death coded according to ICD-9/10 criteria. By the end of 2016, 3,555 participants had died. Of these, 288 (214 males, 74 females) died by suicide (incidence rate = 15.6 per 100,000 person-years, 95% Confidence Interval [CI] = 13.9-17.5). In adjusted models, male sex (Hazard Ratio [HR] = 2.98, CI: 2.26-3.93), White race (HR = 2.14, CI = 1.63-2.83), low parental education (HR = 2.23, CI = 1.38-3.62), manual parental occupation (HR = 1.38, CI = 1.05-1.82), being a younger sibling (HR = 1.52, CI = 1.10-2.11), higher rates of pregnancy complications (HR = 2.36, CI = 1.08-5.16), and smoking during pregnancy (HR = 1,28, CI = 0.99-1.66) were independently associated with suicide risk, whereas birth and neonatal complications were not. Consistent with the developmental origins of psychiatric disorders, vulnerability to suicide mortality is established early in development. Both sociodemographic and pregnancy factors play a role in this risk, which underscores the importance of considering life course approaches to suicide prevention, possibly including provision of high-quality prenatal care, and alleviating the socioeconomic burdens of mothers and families.

No association between maternal and child PFAS concentrations and repeated measures of ADHD symptoms at age 2½ and 5 years in children from the Odense Child Cohort

INTRODUCTION

The potential impact of exposure to perfluoroalkyl substances (PFAS) on childhood Attention-Deficit Hyperactivity-Disorder (ADHD) is unclear and deserves scrutiny. The majority of previously conducted longitudinal studies found no association between maternal serum-PFAS concentrations and ADHD symptoms in the offspring, but some studies observed possible associations with postnatal PFAS exposures, mainly in girls.

OBJECTIVE

To investigate the association between maternal and child serum concentrations of five PFAS and symptoms of ADHD at ages 2½ and 5 years.

METHODS

In the Odense Child Cohort (OCC) women were recruited in early pregnancy in 2010-12 and their children are being prospectively followed. Mothers donated serum samples in the first trimester and children at age 18 months to be analyzed for perfluorohexane sulfonic acid (PFHxS), perfluorooctanesulfonic acid (PFOS), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA) and perfluorodecanoic acid (PFDA). Parents completed the Child Behavior Check List for ages 1.5-5 years (CBCL/1½-5), including a 6-item ADHD symptom scale at age 2½ years and again at 5 years. Negative binomial and logistic regression models taking account of repeated measures were used to investigate the association between maternal and child serum-PFAS concentrations and the ADHD symptom score. Effect modification by child sex was investigated as well.

RESULTS

A total of 1138 mother-child pairs were included. At age 2½ years, 17.4% of the children had an ADHD scale score ≥ 5 (equivalent to the 90th percentile), whereas the proportion was 15.8% at age 5. We found no association between either maternal or child PFAS concentrations in serum and symptoms of ADHD at age 2½ or 5 years, and no evidence of effect modification by sex.

CONCLUSION

We found no evidence of an association between early-life PFAS exposure and the risk of developing symptoms of ADHD.

Early-Life Environmental and Child Factors Associated with the Presence of Disruptive Behaviors in Seven-Year-Old Children with Autistic Traits in the Avon Longitudinal Study of Parents and Children

We studied the association of early-life environmental and child factors with disruptive behaviors in children with autistic traits around age 7, in the Avon Longitudinal Study of Parents and Children (n = 6,401). Logistic regression with the least absolute shrinkage and selection operator indicated that disruptive behaviors were associated with prenatal smoking, no seafood-consumption during pregnancy, breech presentation at delivery, neonatal feeding problems, low social-economic situation, suboptimal preschool family environment, maternal depression, maternal antisocial behavior, male sex, and difficult child temperament. Compared to controls, male sex, maternal depression, and suboptimal preschool family environment were related to autistic traits without disruptive behaviors. Thus, there may be a difference in early-life factors related to autism spectrum disorder with and without disruptive behaviors.

Exploring the Effects of Pharmacological, Psychosocial, and Alternative/Complementary Interventions in Children and Adolescents With Attention-Deficit/Hyperactivity Disorder: Meta-Regression Approach

BACKGROUND

There have been various therapies for attention-deficit/hyperactivity disorder (ADHD), but the previous meta-analysis of ADHD efficacy remains unclear. This study aims to systemically meta-regress the effect sizes (ES) of psychostimulant pharmacotherapy (methylphenidate and lisdexamfetamine), non-stimulant pharmacotherapy (atomoxetine and alpha-2 agonists), psychosocial therapy (parental behavioral therapy [PBT]), combination therapy (psychostimulant plus PBT), and alternative/complementary interventions to determine the right treatment for ADHD.

METHODS

We searched various ADHD interventions from the MEDLINE and PubMed databases (National Center for Biotechnology Information) between January 1, 1980, and July 30, 2018. Following the meta-analysis of random effects, the meta-regression analyses were used to explore factors potentially influencing treatment efficacy. The confounding variables included type of treatment, type of study, age, type of symptom scale used, and year of publication.

RESULTS

A total of 107 trials (n = 9883 participants) were included. After adjustment, compared with the psychostimulant therapy (28 trial, 2134 participants), non-stimulant pharmacotherapy (28 trials, 4991 participants) and alternative/complement intervention (25 trials, 1195 participants) were less effective by the ES of -0.384 (P = .004) and -0.419 (P = .028), respectively. However, compared with psychostimulant, PBT (19 trials, 1122 participants; ES = -0.308, P = .095) and the combination of psychostimulant and PBT (7 trials, 441participants; ES = -0.196, P = .209) did not differ significantly.

CONCLUSIONS

Psychostimulant therapy surpassed non-stimulant pharmacotherapy and alternative/complement intervention. Psychostimulant therapy, PBT, and the combination of psychostimulant therapy and PBT appear to be similar in efficacy according to this meta-regression.

Prevalence of conduct problems and social risk factors in ethnically diverse inner-city schools

Background

In the UK, around 5% of 11–16-year olds experience conduct problems of clinical importance. However, there are limited data on prevalence of conduct problems by ethnic group, and how putative social risk factors may explain any variations in prevalence. This study has two main aims: (1) to estimate the prevalence and nature of conduct problems overall, and by ethnic group and gender, among adolescents in diverse inner-city London schools; (2) to assess the extent to which putative risk factors - racial discrimination, socioeconomic status, parental control, and troublesome friends - explain any observed differences in prevalence of conduct problems between ethnic groups.

Methods

This study uses baseline data from REACH, an accelerated cohort study of adolescent mental health in inner-city London. Self-report questionnaire data were collected on conduct problems and a range of distinct putative social risk factors (including racial discrimination, free school meals, troublesome friends, and parental care and control). A total of 4353 pupils, 51% girls, aged 11–14 participated. We estimated prevalence of conduct problems and used multilevel logistic regression to examine differences by ethnicity and gender and associations with putative risk factors.

Results

Prevalence of conduct problems in inner-city schools was around three times higher than reported in national studies (i.e., 16% [95%CI: 15·2–17·5] vs. 5% [95%CI 4·6–5·9]). Compared with overall prevalence, conduct problems were lower among Indian/Pakistani/Bangladeshi (RR: 0.53 [95% CI:0.31–0.87]) and white British (RR: 0.65 [0.51–0.82]) groups, and higher among black Caribbean (RR: 1.39 [95%CI:1.19–1.62]) and mixed white and black (RR: 1.29 [95% CI: 1.02–1.60]) groups. Risk of conduct problems was higher among those who were exposed to racial discrimination compared with those who were not (RR: 1.95 [95% CI: 1.59–2.31]).

Conclusions

Conduct problems are markedly more common in inner-city schools, and variations in the prevalence of conduct problems are, to some extent, rooted in modifiable social contexts and experiences, such as experiences of racial discrimination.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-10834-5.

Health outcomes of smoking during pregnancy and the postpartum period: an umbrella review

BACKGROUND

Smoking during pregnancy (SDP) and the postpartum period has serious health outcomes for the mother and infant. Although some systematic reviews have shown the impact of maternal SDP on particular conditions, a systematic review examining the overall health outcomes has not been published. Hence, this paper aimed to conduct an umbrella review on this issue.

METHODS

A systematic review of systematic reviews (umbrella review) was conducted according to a protocol submitted to PROSPERO ( CRD42018086350 ). CINAHL, EMBASE, MEDLINE, PsycINFO, Web of Science, CRD Database and HMIC databases were searched to include all studies published in English by 31 December 2017, except those focusing exclusively on low-income countries. Two researchers conducted the study selection and quality assessment independently.

RESULTS

The review included 64 studies analysing the relationship between maternal SDP and 46 health conditions. The highest increase in risks was found for sudden infant death syndrome, asthma, stillbirth, low birth weight and obesity amongst infants. The impact of SDP was associated with the number of cigarettes consumed. According to the causal link analysis, five mother-related and ten infant-related conditions had a causal link with SDP. In addition, some studies reported protective impacts of SDP on pre-eclampsia, hyperemesis gravidarum and skin defects on infants. The review identified important gaps in the literature regarding the dose-response association, exposure window, postnatal smoking.

CONCLUSIONS

The review shows that maternal SDP is not only associated with short-term health conditions (e.g. preterm birth, oral clefts) but also some which can have life-long detrimental impacts (e.g. obesity, intellectual impairment).

IMPLICATIONS

This umbrella review provides a comprehensive analysis of the overall health impacts of SDP. The study findings indicate that while estimating health and cost outcomes of SDP, long-term health impacts should be considered as well as short-term effects since studies not including the long-term outcomes would underestimate the magnitude of the issue. Also, interventions for pregnant women who smoke should consider the impact of reducing smoking due to health benefits on mothers and infants, and not solely cessation.

An Examination of Peer Victimization and Internalizing Problems through a Racial Equity Lens: Does School Connectedness Matter?

Although research has given ample consideration to the association between peer victimization and internalizing problems, little is known about the mediating and moderating influences on this relationship. This study investigated whether peer victimization at age 9 indirectly related to internalizing problems at age 15 via school connectedness and whether the direct and indirect associations between peer victimization and internalizing problems were moderated by race. Data were drawn from the Fragile Families and Child Wellbeing Study, which included 2467 adolescents. The sample was equally divided between male and female and 82% identified as Black and Hispanic. Results indicated that the predictive effect of peer victimization over a 6-year period on teen depression and anxiety was explained by increased school connectedness. Furthermore, there was a moderating effect of race on the direct effect of school connectedness and teen depression and anxiety. For both White and ethnic minority youth, increased school connectedness was associated with less teen depression and anxiety. However, this effect was weaker for ethnic minority students in comparison to White students in both moderated mediation models. The moderated mediation results for teen anxiety showed a greater differential effect among race. The findings have important implications, which are discussed.

Disruptive Behavior in Siblings Discordant for Exposure to Maternal Smoking During Pregnancy: A Multi-rater Approach

INTRODUCTION

Maternal smoking during pregnancy (SDP) is associated with disruptive behavior. However, there is debate whether the SDP-disruptive behavior association is a potentially causal pathway or rather a spurious effect confounded by shared genetic and environmental factors.

AIMS AND METHODS

The Missouri Mothers and Their Children Study is a sibling comparison study that includes families (n = 173) selected for sibling pairs (aged 7-16 years) discordant for SDP. Critically, the sibling comparison design is used to disentangle the effects of SDP from familial confounds on disruptive behavior. An SDP severity score was created for each child using a combination of SDP indicators (timing, duration, and amount of SDP). Multiple informants (parents and teachers) reported on disruptive behavior (i.e., DSM-IV semi-structured interview, the Child Behavior Checklist, and Teacher Report Form).

RESULTS

The variability in disruptive behavior was primarily a function of within-family differences (66%-100%). Consistent with prior genetically informed approaches, the SDP-disruptive behavior association was primarily explained by familial confounds (genetic and environmental). However, when using a multi-rater approach (parents and teachers), results suggest a potentially causal effect of SDP on disruptive behavior (b = 0.09, SE = 0.04, p = 0.03). The potentially causal effect of SDP remained significant in sensitivity analyses.

DISCUSSION

These findings suggest that familial confounding likely plays a complex role in the SDP-disruptive behavior association when examining both parent and teacher reports of behavior. Importantly, the current study highlights the importance of multiple raters, reflecting a more comprehensive measure of complex behaviors (e.g., disruptive behavior) to examine the teratogenic effects of SDP.

IMPLICATIONS

Our study provides additional evidence that controlling for genetic and family factors is essential when examining the effect of SDP on later behavioral problems, as it explains a portion of the association between SDP and later behavioral problems. However, we found a significant association between SDP and disruptive behavior when using a multi-rater approach that capitalizes on both parent and teacher report, suggesting that parent and teacher ratings capture a unique perspective that is important to consider when examining SDP-behavior associations.

Obstetric complications and subsequent risk of mood disorders for offspring in adulthood: a comprehensive overview

Background: A number of studies reported obstetric complications (OCs) to be a risk factor for the development of psychiatric conditions in the adulthood, including mood disorders.Aim: The aim of this study was to review the literature about the link between OCs during the perinatal period (items of Lewis-Murray scale) and the future risk of developing a mood disorder in adulthood, such as the major depressive disorder (MDD) or the bipolar disorder (BD).Methods: A research in the main database sources has been conducted to obtain an overview of the association mentioned above.Results: Few studies have investigated the role of OCs in the development of mood disorders in adulthood. The most robust evidence is that low birth weight (LBW) and preterm birth may be risk factors for the development of MDD in the future, even if some of the available data come from studies with small sample sizes or a retrospective design.Conclusion: OCs may confer a risk of developing mood disorders in adulthood. Future research should confirm these preliminary findings and clarify if other obstetric or neonatal complications (e.g. cyanosis or newborn epileptic seizures) may have a role in the future onset of mood disorders.

Perinatal biomarkers implying 'Developmental Origins of Health and Disease' consequences in intrauterine growth restriction

The intrauterine-growth-restricted (IUGR) state, particularly the asymmetric one, has been associated with 'Developmental Origins of Health and Disease' (DOHaD) consequences later in life. Several environmental factors, acting during the phase of foetal developmental plasticity interact with genotypic variation, 'programme' tissue function and change the capacity of the organism to cope with its environment. They may be responsible for chronic illness risk in adulthood. Detection of possible future DOHaD consequences at a very early age, by applying relevant biomarkers, is of utmost importance. This review focuses on biomarkers possibly predicting consequences from bone, psychoneural system and lung. Although no concrete biomarker has been identified for bone disorders in adulthood, reduced brain-derived neurotrophic factor (BDNF) concentrations in cord blood and BDNF DNA methylation might predict schizophrenia and possibly depression, bipolar disorder and autism. High surfactant protein D (SP-D) concentrations in cord blood of IUGR foetuses/neonates could point to structural lung immaturity, resulting to asthma and chronic obstructive pulmonary disease in adult life.

A Systematic Review of Reviews of the Outcome of Severe Neglect in Underresourced Childcare Institutions

The aim of the systematic review described in this article was to determine the outcomes for individuals exposed to severe neglect in congregate care institutions such as orphanages. In this context, severe neglect refers to failure to meet children's basic physical, developmental, and emotional needs due to inadequate resources. In this systematic review of previous systematic reviews and meta-analyses, searches of 10 databases were conducted, 18 papers that met inclusion and exclusion criteria were selected for review, their quality was assessed, and data were extracted and synthesized. The 550 primary studies included in the 18 systematic reviews and meta-analyses were relatively well designed, allowing confidence to be placed in their results. Severe neglect was associated with a wide range of problems in the domains of physical development, cognitive development, attachment, and mental health. The severity of adverse outcomes was partly influenced by the duration and severity of deprivation and a constellation of risk and protective factors. Prevention policies should aim to eliminate large underresourced congregate care institutions for infants. In taking steps toward this, policies should aim to adequately resource congregate care institutions to meet children's developmental needs for nutrition, stimulation, and attachment to a stable primary caregiver with adequate parenting skills and training. Early placement in adoptive or foster families, with access to routine physical and mental health-care service available in developed countries, is the most viable effective intervention for child survivors of severe neglect.

Aggressive behavior during toddlerhood: Interrelated effects of prenatal risk factors, negative affect, and cognition

Prenatal risk, temperamental negative affect, and specific cognitive abilities have all individually been identified as predictors of behavior problems during early childhood, but less is known about their interplay in relation to aggression during toddlerhood. This study examined the main and interaction effects of prenatal risk, negative affect, inhibitory control, attention, and vocabulary in the prediction of aggression in 150 children (75 boys). During pregnancy, a cumulative risk index was calculated based on the presence of 10 well-established maternal risk factors, such as prenatal substance use, maternal psychiatric disorder, and financial problems. Negative affect was measured at 6 and 20 months using maternal report. Child cognition was examined at 30 months using laboratory tasks for inhibitory control and attention, and a questionnaire was administered to assess vocabulary. In addition, mothers reported on their children's aggressive behavior at 30 months. Higher prenatal risk and negative affect at 20 months and, to a lesser extent, at 6 months were related to more aggression at 30 months. Poorer inhibitory control and, to a lesser extent, vocabulary at 30 months also predicted higher levels of aggressive behavior. Two-way interaction effects were found for cumulative risk and inhibitory control, negative affect (at 20 months) and inhibitory control, and negative affect (at 6 months) and vocabulary: aggressive behavior was most pronounced when combinations of high prenatal risk, high negative affect, and poor cognition were present. These results suggest that the impact of prenatal risk and child temperament depends in part on child's cognitive development during toddlerhood.

Maternal urinary concentrations of pyrethroid and chlorpyrifos metabolites and attention deficit hyperactivity disorder (ADHD) symptoms in 2-4-year-old children from the Odense Child Cohort

BACKGROUND

Pyrethroids and chlorpyrifos are widely used insecticides, but the potential impact of prenatal exposure on child neurodevelopment has only been addressed in few longitudinal studies.

OBJECTIVES

To investigate associations between prenatal exposure to pyrethroids and chlorpyrifos and traits of ADHD in 2-4-year-old children.

METHODS

Metabolites of chlorpyrifos and pyrethroids were measured in maternal urine collected at gestational week 28 among 1207 women from the Odense Child Cohort. Of these, 948 completed the Child Behavior Check List for ages 1.5-5 years (CBCL: 1½-5). Negative binomial and logistic regression models were used to estimate relative differences in ADHD problem scores (CBCL: 1½-5 subscale) expressed as the ratio of expected scores between exposure groups and the odds (OR) of scoring equal to or above the 90^th percentile in relation to maternal urinary metabolite concentrations (continuous ln₂-transformed or categorized into tertiles). The analyses were adjusted for maternal education level, parental psychiatric diagnosis, child age and sex.

RESULTS

The chlorpyrifos metabolite, 3,5,6-trichloro-2-pyridinol (TCPY), the generic pyrethroid metabolite, 3-phenoxybenzoic acid (3-PBA), and the metabolite of trans-isomers of permethrin, cypermethrin, and cyfluthrin, trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane-1-carboxylic acid (trans-DCCA), were detected in 90%, 94%, and 11%, respectively, of the urine samples. Each doubling in maternel 3-PBA concentration was associated with a 3% increase in the ADHD score (Ratio: 1.03 (95% CI: 1.00,1.07)) and a 13% higher odds of having a ADHD score ≥ the 90^th percentile (OR: 1.13 (1.04,1.38)). Similar associations were seen for 3-PBA as categorical variable (p-trend=0.052 in negative binimoal regression, p-trend=0.007 in logistic regression). Furthermore, concurrent concentrations of 3-PBA and TCPY above their medians were associated with higher ADHD score (Ratio: 1.20 (1.04, 1.38)) and higher odds of scoring ≥ the 90^th percentile (OR: 1.98 (1.26, 3.11)). Maternal trans-DCCA above the detection level increased the odds of ADHD symptoms (OR: 1.76 (1.08, 2.86)). The associations were not modified by sex.

CONCLUSIONS

Prenatal exposure to pyrethroids was associated with ADHD related traits at 2-4 years of age. Considering the widespread use of pyrethroids these results are of concern.

Conduct disorder

Conduct disorder (CD) is a common and highly impairing psychiatric disorder that usually emerges in childhood or adolescence and is characterized by severe antisocial and aggressive behaviour. It frequently co-occurs with attention-deficit/hyperactivity disorder (ADHD) and often leads to antisocial personality disorder in adulthood. CD affects ~3% of school-aged children and is twice as prevalent in males than in females. This disorder can be subtyped according to age at onset (childhood-onset versus adolescent-onset) and the presence or absence of callous-unemotional traits (deficits in empathy and guilt). The aetiology of CD is complex, with contributions of both genetic and environmental risk factors and different forms of interplay among the two (gene-environment interaction and correlation). In addition, CD is associated with neurocognitive impairments; smaller grey matter volume in limbic regions such as the amygdala, insula and orbitofrontal cortex, and functional abnormalities in overlapping brain circuits responsible for emotion processing, emotion regulation and reinforcement-based decision-making have been reported. Lower hypothalamic-pituitary-adrenal axis and autonomic reactivity to stress has also been reported. Management of CD primarily involves parent-based or family-based psychosocial interventions, although stimulants and atypical antipsychotics are sometimes used, especially in individuals with comorbid ADHD.

Adverse family life events during pregnancy and ADHD symptoms in five-year-old offspring

BACKGROUND

Prenatal exposure to maternal adverse life events has been associated with offspring ADHD, but the role of familial confounding is unclear. We aimed to clarify if adverse life events during pregnancy are related to ADHD symptoms in offspring, taking shared familial factors into account.

METHOD

Data were collected on 34,751 children (including 6,427 siblings) participating in the population-based Norwegian Mother and Child Cohort Study. During pregnancy, mothers reported whether they had experienced specific life events. We assessed ADHD symptoms in five-year-old children with the Conners' Parent Rating Scale-Revised: short form. We modeled the associations between life events and mean ADHD scores with ordinary linear regression in the full cohort, and with fixed-effect linear regression in sibling comparisons to adjust for familial confounding.

RESULTS

Children exposed to adverse life events had higher ADHD scores at age 5, with the strongest effect observed for financial problems (mean differences 0.10 [95% CI: 0.09, 0.11] in adjusted model), and the weakest for having lost someone close (0.02 [95% CI 0.01, 0.04] in adjusted model). Comparing exposure-discordant siblings resulted in attenuated estimates that were no longer statistically significant (e.g. mean difference for financial problems -0.03 [95% CI -0.07, 0.02]). ADHD scores increased if the mother had experienced the event as painful or difficult, and with the number of events, whereas sibling-comparison analyses resulted in estimates attenuated toward the null.

CONCLUSIONS

These results suggest that the association between adverse life events during pregnancy and offspring ADHD symptoms is largely explained by familial factors.

Relation Between Oppositional/Conduct Behaviors and Executive Function Among Youth with Histories of Heavy Prenatal Alcohol Exposure

BACKGROUND

Youth with heavy prenatal alcohol exposure have high rates of behavioral concerns and psychopathology, including increased oppositional and conduct behaviors. The relation between those concerns and executive function (EF) deficits is unknown. We investigated the association of oppositional and conduct behavior and EF in adolescents to inform targeted intervention.

METHODS

Subjects (N = 267) ages 10 to 17 years comprised 3 groups: alcohol-exposed with oppositional/conduct behaviors (AE+), alcohol-exposed without oppositional/conduct behaviors (AE-), and controls (CON). Group differences on direct neuropsychological (Delis-Kaplan Executive Function System [D-KEFS]) and indirect parent-report (Behavior Rating Inventory of Executive Function [BRIEF]) EF measures were tested with multivariate analysis of covariances, followed by univariate analysis of variances and pairwise comparisons. The contribution of attention-deficit/hyperactivity disorder (ADHD) within the AE groups was assessed in secondary analyses.

RESULTS

On the D-KEFS, there was an omnibus main effect of group, with significant main effects on 3 of 6 variables (CON>AE+, AE-). Within the AE groups, ADHD did not alter the results. On the BRIEF, there was an omnibus significant main effect of group, with significant main effects on all scales (CON<AE-<AE+). Within the AE groups, the AE+ group had higher BRIEF scores (i.e., more difficulty) than the AE- group on 4 of 8 subscales when accounting for presence of ADHD.

CONCLUSIONS

EF deficits in youth with histories of prenatal alcohol exposure were confirmed using direct and indirect measures. Oppositional/conduct behaviors related to EF deficits on indirect but not direct EF measures. Greater understanding of the contribution of concurrent psychopathology to long-term outcomes for alcohol-exposed youth requires further investigation.

Do preschoolers with adverse birth outcomes have more distress during dental examination?

PURPOSE

Studies assessing the influence of neonatal complications on children's dental behaviour are lacking. We aimed to investigate whether prematurity, birth weight, and history of neonatal intensive care unit (NICU) hospitalisation are associated with distress during dental examination in children.

METHODS

This preliminary longitudinal, retrospective study included 42 5- and 6-year-old children. Distress during dental examination was assessed using the observational FLACC Pain Assessment Tool through video files. Children self-reported their pain (Faces Pain Scale-Revised) at the end of the session. Information about neonatal complications was obtained through medical records. Bivariate analysis was performed (P < 0.05).

RESULTS

Children with low birth weight (P = 0.047) and toothache history (P = 0.005) had higher frequency of distress during dental examination. There was no association between distress, prematurity and history of NICU hospitalisation (P > 0.05).

CONCLUSIONS

Health professionals can help to disseminate the knowledge that children with history of low birth weight are more prone to perceive distress with apparently painless procedures.

Neonatal handling impairs intradimensional shift and alters plasticity markers in the medial prefrontal cortex of adult rats

Stress response can be modulated by neonatal/childhood events. Neonatal handling (NH) is an animal model in which the animals are subjected to brief separations from the dam during the first days of life, and it leads to lower emotionality and behavioral changes in adulthood. The aim of this study was to observe if early events, such as (NH), may program associative learning and behavioral flexibility in adult male rats and if these changes could be related to altered neurochemistry in the medial prefrontal cortex (mPFC). We evaluated proteins related to synaptic plasticity (brain-derived neurotrophic factor [BDNF] and synaptophysin [SYP]) as well as Na⁺/K⁺-ATPase activity. Additionally, we evaluated proteins related to the dopaminergic system (tyrosine hydroxylase [TH] and phosphorylated TH [pTH]), since this system appears to be affected in some neonatal interventions. Neonatally handled animals exhibited impairment in simple discrimination and intradimensional shift but not in reversal or compound discrimination; in addition, no alteration in switching from an egocentric spatial to a cued strategy was observed. These effects were accompanied by a decrease in SYP levels and Na⁺/K⁺-ATPase activity, suggesting reduced synaptic function. These results indicate that NH increases attention to irrelevant stimuli and/or impairs associative learning, and this is accompanied by neurochemical alterations in the (mPFC).

Conduct disorder in adolescent females: current state of research and study design of the FemNAT-CD consortium

Conduct disorder (CD) is a common and highly impairing psychiatric disorder of childhood and adolescence that frequently leads to poor physical and mental health outcomes in adulthood. The prevalence of CD is substantially higher in males than females, and partly due to this, most research on this condition has used all-male or predominantly male samples. Although the number of females exhibiting CD has increased in recent decades, the majority of studies on neurobiological measures, neurocognitive phenotypes, and treatments for CD have focused on male subjects only, despite strong evidence for sex differences in the aetiology and neurobiology of CD. Here, we selectively review the existing literature on CD and related phenotypes in females, focusing in particular on sex differences in CD symptoms, patterns of psychiatric comorbidity, and callous-unemotional personality traits. We also consider studies investigating the neurobiology of CD in females, with a focus on studies using genetic, structural and functional neuroimaging, psychophysiological, and neuroendocrinological methods. We end the article by providing an overview of the study design of the FemNAT-CD consortium, an interdisciplinary, multi-level and multi-site study that explicitly focuses on CD in females, but which is also investigating sex differences in the causes, developmental course, and neurobiological correlates of CD.

Glucocorticoid metabolites in newborns: A marker for traffic noise related stress?

BACKGROUND

Traffic noise has been associated with an increased risk for several non-auditory health effects, which may be explained by a noise-induced release of stress hormones (e.g. glucocorticoids). Although several studies in children and adults have indicated an increased secretion of glucocorticoids after exposure to noise, information regarding newborns is scarce.

OBJECTIVES

To investigate the association between residential exposure to road traffic noise and postnatal stress response, as assessed by the concentration of glucocorticoids at five weeks of age.

METHODS

Residential noise exposure was estimated for each infant based on spatially detailed modeled data. Adjusted multivariable linear regression models were used to estimate the association between noise exposure and the concentration of nine glucocorticoid metabolites measured in urine of 165 infants from a prospective birth cohort in Bern, Switzerland. Noise exposure (Lden, dB) was categorized into tertiles: low (reference), medium and high.

RESULTS

Indications of a positive association were found between high road traffic noise and cortisol (% change relative to the reference: 12.1% [95% confidence interval: -10.3, 40.1%]) and cortisone (22.6% [-1.8, 53.0%]), but just the latter was borderline significant. Borderline significant associations were also found between downstream metabolites and higher road traffic noise levels; associations were found to be both positive (i.e. for β-cortolone (51.5% [-0.9, 131.5%])) and negative (i.e. for α-cortolone (-18.3% [-33.6, 0.6%]) and tetrahydrocortisol (-23.7% [-42.8, 1.9%])).

CONCLUSIONS

Our findings suggest a potential association between exposure to higher road traffic noise levels and changes in glucocorticoid metabolism in early postnatal life. A possible physiological relevance and associations with short- and long-term adverse health effects in a larger study population need to be further investigated.

Pregnancy risk factors in relation to oppositional-defiant and conduct disorder symptoms in the Avon Longitudinal Study of Parents and Children

BACKGROUND

Pregnancy factors have been implicated in offspring oppositional-defiant disorder (ODD) and conduct disorder (CD) symptoms. Literature still holds notable limitations, such as studying only a restricted set of pregnancy factors, use of screening questionnaires which assess broadly defined outcome measures, and lack of control for disruptive behavior comorbidity and genetic confounds. We aimed to address these gaps by prospectively studying a broad range of pregnancy factors in relation to both offspring ODD and CD symptomatology in the Avon Longitudinal Study of Parent and Children.

METHODS

Outcomes were ODD and CD symptom scores at age 7;9 years using the Development and Well-Being Assessment interview. We analyzed maternal (N ≈ 6300) and teacher ratings (N ≈ 4400) of ODD and CD scores separately using negative binomial regression in multivariable models. Control variables included comorbid attention-deficit/hyperactivity disorder symptoms, ODD or CD symptoms as appropriate, and genetic risk scores based on an independent CD genome-wide association study.

RESULTS

Higher ODD symptom scores were linked to paracetamol use (IRR = 1.24 [98.3% confidence interval 1.05-1.47], P = 0.002, teacher ratings) and life events stress (IRR = 1.22 [1.07-1.39], P = 0.002, maternal ratings) during pregnancy. Higher CD symptom scores were linked to maternal smoking (IRR = 1.33 [1.18-1.51], P < 0.001, maternal ratings), life events stress (IRR = 1.24 [1.11-1.38], P < 0.001, maternal ratings) and depressive symptoms (IRR = 1.14 [1.01-1.30], P = 0.006, maternal ratings) during pregnancy.

CONCLUSIONS

Common and potentially preventable pregnancy risk factors were independently related to both offspring ODD and CD symptomatology in children from the general population. Future studies should further address genetic confounds and confounding by environmental factors later in life.

Serum levels of cortisol, dehydroepiandrosterone, and oxytocin in children with attention-deficit/hyperactivity disorder combined presentation with and without comorbid conduct disorder

The present study aimed to investigate serum cortisol, dehydroepiandrosterone (DHEA), and oxytocin levels of children with attention-deficit/hyperactivity disorder (ADHD) combined presentation and those diagnosed with ADHD combined presentation and coexisting conduct disorder. A total of 74 drug-naive children with ADHD combined presentation alone, 32 children with ADHD combined presentation + conduct disorder, and 42 healthy controls were included. The severities of ADHD and conduct disorder symptoms were assessed via parent- and teacher-rated questionnaires. The severity of aggression, anxiety, and depression symptoms of the children were assessed by the self-report inventories. Independent of potential confounders, including age, sex, pubertal stage, and severity of depression and anxiety, serum oxytocin levels of the ADHD combined presentation + conduct disorder group were significantly lower than those of both the ADHD combined presentation alone and control groups. There was also a trend for the ADHD combined presentation + conduct disorder group to show lower serum DHEA levels than that of the ADHD combined presentation alone group. However, serum cortisol levels did not show significant alterations among the groups. These findings suggest that oxytocin and DHEA may play a role in the pathophysiology of conduct disorder, at least in the presence of ADHD combined presentation.

Perinatal hypoxia as a risk factor for psychopathology later in life: the role of dopamine and neurotrophins

Brain development is influenced by various prenatal, intrapartum, and postnatal events which may interact with genotype to affect the neural and psychophysiological systems related to emotions, specific cognitive functions (e.g., attention, memory), and language abilities and thereby heighten the risk for psychopathology later in life. Fetal hypoxia (intrapartum oxygen deprivation), hypoxia-related obstetric complications, and hypoxia during the early neonatal period are major environmental risk factors shown to be associated with an increased risk for later psychopathology. Experimental models of perinatal hypoxia/ischemia (PHI) showed that fetal hypoxia-a consequence common to many birth complications in humans-results in selective long-term disturbances of the dopaminergic systems that persist in adulthood. On the other hand, neurotrophic signaling is critical for pre- and postnatal brain development due to its impact on the process of neuronal development and its reaction to perinatal stress. The aim of this review is (a) to summarize epidemiological data confirming an association of PHI with an increased risk of a range of psychiatric disorders from childhood through adolescence to adulthood, (b) to present immunohistochemical findings on human autopsy material indicating vulnerability of the dopaminergic neurons of the human neonate to PHI that could predispose infant survivors of PHI to dopamine-related neurological and/or cognitive deficits in adulthood, and

Which children and young people are excluded from school? Findings from a large British birth cohort study, the Avon Longitudinal Study of Parents and Children (ALSPAC)

BACKGROUND

Exclusion from school is increasingly recognized as pertinent to child health. National educational data reveal that boys, children who are looked-after, living in poverty, have special educational needs, or from certain ethnic minorities, are disproportionately excluded from school. As population-based data on the wider characteristics of excluded children are scarce, we aimed to describe predictors of school exclusion in the Avon Longitudinal Study of Parents and Children.

METHOD

Avon Longitudinal Study of Parents and Children, a prospective U.K. population-based birth cohort study, collected parent reports of permanent school exclusions by 8 years and parent and self-reports of permanent and fixed-term exclusions in the preceding 12 months at 16 years. Potential risk factors were examined for associations with exclusion using logistic regression, with a focus on child mental health and neurodevelopment.

RESULTS

Analyses were based on all available data on 53/8,245 (0.6%) pupils excluded from school by 8 years and 390/4,482 (8.7%) at 16 years. Key factors associated with exclusion at both time points included male gender, lower socio-economic status, maternal psychopathology, mental health and behavioural difficulties, psychiatric disorder, social communication difficulties, language difficulties, antisocial activities, bullying/being bulled, lower parental engagement with education, low school engagement, poor relationship with teacher, low educational attainment, and special educational needs (all p < .05).

CONCLUSION

Exclusion from school was associated with child, family and school-related factors identifiable at, or prior to, primary school age. Child health professionals have an important role in the holistic, multidisciplinary assessment of children who are at risk of exclusion from school. Mental health and neurodevelopmental difficulties should be recognized and supported, to improve the health and educational outcomes among this vulnerable group.

A critical review of developmental exposure to particulate matter, autism spectrum disorder, and attention deficit hyperactivity disorder

Autism spectrum disorder (ASD) and attention deficit (hyperactivity) disorder (ADD/ADHD) are key focuses of current health research due to their increasing prevalence. The objective of this systematic literature search and critical review was to evaluate whether the human epidemiologic data indicate a pattern of association between ASD or ADD/ADHD and developmental exposure to particulate matter (PM), with a focus on exposures encountered before the age of three. A MEDLINE and EMBASE search was conducted; following preliminary and full-text screening, 14 relevant articles were identified for review. Three of the 14 studies were prospective cohort studies evaluating exposure to PM₁₀; 11 studies had a case-control design. There was no consistent association between developmental PM exposure and ASD across the three of the cohort studies. Seven of the case-control studies examined the relationship between PM_2.5 and/or PM₁₀ and ASD; four examined the relationship between developmental diesel PM exposure and ASD. Overall, there was low external consistency in results among studies of PM_2.5/PM₁₀ and ASD, with some reporting high internal consistency without significant associations, others showing associations with high internal consistency for specific exposure windows only (e.g., third trimester), and still others showing high consistency for moderate to strong associations between PM and ASD. The majority of studies reporting significant results had low effect sizes in conjunction with small sample sizes. The four studies of diesel PM and ASD also had low external consistency of results. Only one study evaluated associations with ADD/ADHD, and it found no significant associations with PM₁₀. The inconsistent findings across studies of developmental exposure to PM and ASD may be attributed to differences in the study populations, exposure assessments, outcome assessments, or chance. Further research is needed to understand the underlying biological mechanisms that lead to ASD and ADD/ADHD and how PM might be involved in those mechanisms, if at all. High-quality epidemiologic studies are also needed to conclusively determine whether developmental PM exposure is a causal factor for ASD or ADD/ADHD, with focus on a well-developed exposure assessment.

The Association Between Prenatal Stress and Externalizing Symptoms in Childhood: Evidence From the Avon Longitudinal Study of Parents and Children

BACKGROUND

It has been suggested that prenatal maternal stress may increase the risk of childhood externalizing disorders, yet no large cohort study has investigated this association across a large range of acute stressors. Our objective was to estimate the association between prenatal stressful events and risk of offspring conduct disorder and hyperactivity.

METHODS

We used data from 10,184 mother-offspring pairs from the United Kingdom-based Avon Longitudinal Study of Parents and Children. Mothers self-reported 42 prenatal stressful life events at 18 weeks' gestation. Symptoms of conduct disorder and hyperactivity in their offspring were measured at 6, 9, 11, 13, and 16 years of age using the Strengths and Difficulties Questionnaire. The primary outcome was membership in high-symptom trajectories of 1) conduct disorder and 2) hyperactivity throughout childhood, identified using latent class growth modeling. Multinomial logistic regression models estimated the association between prenatal stress and both conduct disorder and hyperactivity, after adjusting for sex, parental education, low birth weight, preterm birth, parental social class, maternal smoking and drinking, maternal mental health, offspring stressful life events, and offspring depressive and anxious symptoms.

RESULTS

Those exposed to the highest quartile of prenatal stress were more likely to belong to the high symptom trajectory for hyperactivity (B = 0.46, p < .05) and conduct disorder (B = 0.88, p < .01), respectively. Prenatal stress further demonstrated a positive, dose-response relationship with symptoms of externalizing disorders at independent time points.

CONCLUSIONS

The findings suggest that prenatal stressful events may be an independent risk factor for offspring externalizing symptoms, regardless of maternal mental health and offspring internalizing.

Conduct problems in youth and the RDoC approach: A developmental, evolutionary-based view

Problems related to aggression in young people are traditionally subsumed under the header of conduct problems, which include conduct disorder and oppositional defiant disorder. Such problems in children and adolescents are an important societal and mental health problem. In this paper we present an evolutionarily informed developmental psychopathology view of conduct problems inspired by the NIMH Research Domain Criteria (RDoC) initiative. We assume that while there are many pathways to conduct problems, chronic or temporary impairments in the domain of social cognition or mentalizing are a common denominator. Specifically, we conceptualize conduct problems as reflecting temporary or chronic difficulties with mentalizing, that is, the capacity to understand the self and others in terms of intentional mental states, leading to a failure to inhibit interpersonal violence through a process of perspective-taking and empathy. These difficulties, in turn, stem from impairments in making use of a normally evolutionarily protected social learning system that functions to facilitate intergenerational knowledge transmission and protect social collaborative processes from impulsive and aggressive action. Temperamental, biological, and social risk factors in different combinations may all contribute to this outcome. This adaptation then interacts with impairments in other domains of functioning, such as in negative and positive valence systems and cognitive systems. This view highlights the importance of a complex interplay among biological, psychological, and environmental factors in understanding the origins of conduct problems. We outline the implications of these views for future research and intervention.

Maternal Smoking During Pregnancy Is Associated With Offspring's Musculoskeletal Pain in Adolescence: Structural Equation Modeling

Introduction

Smoking and behavioral problems are related to musculoskeletal (MS) pain in adolescence. Maternal smoking during pregnancy (MSDP) is associated with offspring's behavioral problems but its relation to MS pain in adolescence is unknown. Our purpose was to investigate whether there is an association between MSDP, the number of pain sites in adolescence, and the factors that potentially mediate this relationship.

Methods

We evaluated the association of MSDP with offspring's MS pain at 16 years among participants of the Northern Finland Birth Cohort 1986 (n = 6436, 3360 girls, 68% of all births) using Chi-square test and independent samples t test. We used structural equation modeling to assess the mediating factors stratified by gender.

Results

MSDP was frequent (22%) associating with paternal smoking (p < .001), externalization problems at 8 years (p = .009 boys, p = .002 girls), offspring's smoking at 16 years (p < .001), externalizing problems at 16 years (p < .001), family's social class (p < .001) and intactness of the family status (p < .001). The mean number of offspring's MS pain sites was higher among adolescents whose mothers had smoked during pregnancy than among those whose mothers were nonsmokers (p = .002 boys, p = .012 girls). The association between MSDP and MS pain at 16 years was mediated by externalizing problems at 8 years (p < .001) and 16 years (p < 0.001).

Conclusions

MSDP increased the risk of offspring's MS pain in adolescence, and the association was mediated by offspring's externalizing problems during childhood and early adolescence.

Implications

This study indicates that MSDP increases the risk of MS pain in adolescence and the effect is mediated by externalizing problems. Our results add to the evidence on harmfulness of MSDP for offspring, and can be used as additional information in interventions aiming to influence MSDP.

Neurodevelopmental Disorders and Environmental Toxicants: Epigenetics as an Underlying Mechanism

The increasing prevalence of neurodevelopmental disorders, especially autism spectrum disorders (ASD) and attention deficit hyperactivity disorder (ADHD), calls for more research into the identification of etiologic and risk factors. The Developmental Origin of Health and Disease (DOHaD) hypothesizes that the environment during fetal and childhood development affects the risk for many chronic diseases in later stages of life, including neurodevelopmental disorders. Epigenetics, a term describing mechanisms that cause changes in the chromosome state without affecting DNA sequences, is suggested to be the underlying mechanism, according to the DOHaD hypothesis. Moreover, many neurodevelopmental disorders are also related to epigenetic abnormalities. Experimental and epidemiological studies suggest that exposure to prenatal environmental toxicants is associated with neurodevelopmental disorders. In addition, there is also evidence that environmental toxicants can result in epigenetic alterations, notably DNA methylation. In this review, we first focus on the relationship between neurodevelopmental disorders and environmental toxicants, in particular maternal smoking, plastic-derived chemicals (bisphenol A and phthalates), persistent organic pollutants, and heavy metals. We then review studies showing the epigenetic effects of those environmental factors in humans that may affect normal neurodevelopment.

Associations between mothers' active engagement with infants at 6 months and children's adjustment to school life at ages 5.5 and 11 years

BACKGROUND

In Japan, students' poor adjustment to school life such as school refusals has been recognized as a nation-wide problem. In this study, we examined the link between the absence of mothers' active engagement with their infants at 6 months and children's risks of poor adjustment toward elementary school life at the ages of 5.5 and 11.

METHODS

We used a Japanese national longitudinal survey (n = 43 132) with 11 years of follow-up. Because of social patterning in how mothers engage with their infants, we employed propensity score matching analyses to control for confounding by socio-economic and other factors. We matched mothers with active engagement and those without on various social and parental characteristics such as educational attainment and household income.

RESULTS AND CONCLUSIONS

Among matched pairs, we observed higher risks of poor adjustment to school life at both 5.5 and 11 years among Japanese children who lacked mothers' active engagement at 6 months. For example, the relative risk was 1.46 [95% confidence interval: 1.10, 1.94] for inability to get along with others in a group setting at the age of 5.5 years and 1.29 [1.10, 1.51] for inability to get along with teachers at the age of 11 years. Our findings corroborate previous findings, which emphasize the importance of providing an enriched environment for infants' social development and may indicate the need for an intervention for caregivers who lack appropriate nurturing skills.

Family and Individual Risk and Protective Factors of Depression among Chinese Migrant Children with Oppositional Defiant Disorder Symptoms

Migrant children reached 35.81 million in China and were vulnerable to serious emotional problems including depression. The present study aimed to identify the family and individual risk and protective factors for depression in an at-risk sample of Chinese migrant children. Participants were 368 children (9.47 ± 1.46 years old, 73.4% boys) who had at least one symptom of Oppositional Defiant Disorder symptoms (ODD) and their parents in Mainland China. Risk and protective factors within both family (i.e., family maltreatment and family functioning) and individual (i.e., automatic thoughts and resilience) perspectives. Family maltreatment and negative automatic thoughts served as risk factors in relation to children's depression. Further, automatic thoughts mediated the relationship between family maltreatment and children's depression. Family functioning (cohesion, but bot adaptability) and individual resilience could buffer the effects of risk factors in the Structure Emotion Model such that both cohesion and resilience moderated the relationship between family maltreatment and children's automatic thoughts only. Our findings highlighted the urgent need to decrease risk factors and increase protective factors of both family and child individual characteristics in prevention and intervention depression among migrant children with ODD symptoms in China.

The interaction between parenting and children's cortisol reactivity at age 3 predicts increases in children's internalizing and externalizing symptoms at age 6

Little is known about the role of stress reactivity in the emergence of psychopathology across early childhood. In this longitudinal study, we tested the hypothesis that child cortisol reactivity at age 3 moderates associations between early parenting and children's internalizing and externalizing symptoms from age 3 to age 6. One hundred and sixty children were assessed at age 3, and 135 children were reassessed at age 6. At age 3, we exposed children to stress-inducing laboratory tasks, during which we obtained four salivary cortisol samples, and parental hostility was assessed using an observational parent-child interaction task. At ages 3 and 6, child psychiatric symptoms were assessed using a clinical interview with parents. The results indicated that the combination of high child cortisol reactivity and high observed parental hostility at age 3 was associated with greater concurrent externalizing symptoms at age 3 and predicted increases in internalizing and externalizing symptoms from age 3 to age 6. Findings highlight that increased stress reactivity, within the context of hostile parenting, plays a role in the emergence of psychopathology from preschool to school entry.

Hippocampal BDNF overexpression or microR124a silencing reduces anxiety- and autism-like behaviors in rats

MicroRNA124a (miR124a) has emerged recently as a key player for multiple neuropsychiatric disorders including depression, anxiety, alcoholism, and cocaine addiction. Although we have previously reported that miR124a and its target the brain-derived neutrophic factor (BDNF) play an important role in autism-like behaviors, the molecular and behavioral dysfunctions remain unknown. The aim of this study was to understand the effects of sustained decreases in miR124a and increases of BDNF in the dentate gyrus (DG) on neonatal isolation-induced anxiety-and autism like behaviors in rats. Here we report that lentiviral-mediated silencing of miR124a in the adult DG attenuated neonatal isolation-induced anxiety-like behavior in the elevated plus maze (EPM) and open-field (OF) tests. Also, miR124a silencing decreased autism-like phenotype in the marble burying test (MBT), self-grooming (SG), and social interaction tests. Pearson's correlations demonstrated that high levels of BDNF, a direct target of miR124a, were negatively correlated with miR124a expression. Interestingly, viral-mediated BDNF overexpression in the DG also reversed the neonatal isolation-induced anxiety-and autism like phenotypes. Collectively, these findings suggest that miR124a, through its target BDNF, may influence neonatal isolation-induced anxiety-and autism like behaviors. In conclusion, these results do support the hypothesis that miR124a in discrete hippocampal areas contributes to anxiety- and autism-like behaviors and may be involved in the neuroadaptations underlying the development of autism spectrum disorders as a persistent and lasting condition, and therefore provide a clearer mechanistic framework for understanding the physiopathology of such psychiatric illnesses.

Risk factors for comorbid oppositional defiant disorder in attention-deficit/hyperactivity disorder

Oppositional defiant disorder (ODD) is highly prevalent in attention-deficit/hyperactivity disorder (ADHD). Individuals with both ADHD and ODD (ADHD + ODD) show a considerably worse prognosis compared with individuals with either ADHD or ODD. Therefore, identification of risk factors for ADHD + ODD is essential and may contribute to the development of (early) preventive interventions. Participants were matched for age, gender, and ADHD-subtype (diagnostic groups), and did not differ in IQ. Predictors included pre- and perinatal risk factors (pregnancy duration, birth weight, maternal smoking during pregnancy), transgenerational factors (parental ADHD; parental warmth and criticism in diagnostic groups), and postnatal risk factors (parental socioeconomic status [SES], adverse life events, deviant peer affiliation). Three models were assessed, investigating risk factors for ADHD-only versus controls (N = 86), ADHD + ODD versus controls (N = 86), and ADHD + ODD versus ADHD-only (N = 90). Adverse life events and parental ADHD were risk factors for both ADHD + ODD and ADHD-only, and more adverse life events were an even stronger risk factor for comorbid ODD compared with ADHD-only. For ADHD + ODD, but not ADHD-only, parental criticism, deviant peer affiliation, and parental SES acted as risk factors. Maternal smoking during pregnancy acted as minor risk factor for ADHD-only, while higher birth weight acted as minor risk factor for ADHD + ODD. No effects of age were present. Findings emphasise the importance of these factors in the development of comorbid ODD. The identified risk factors may prove to be essential in preventive interventions for comorbid ODD in ADHD, highlighting the need for parent-focused interventions to take these factors into account.