Determining the impact of prenatal tobacco exposure on self-regulation at 6 months

Exploring the interplay of dopaminergic genotype and parental behavior in relation to executive function in early childhood

Child genotype is an important biologically based individual difference conferring differential sensitivity to the effect of parental behavior. This study explored dopaminergic polygenic composite × parental behavior interactions in relation to young children's executive function. Participants were 135 36-month-old children and their mothers drawn from a prospective cohort followed longitudinally from pregnancy. A polygenic composite was created based on the number of COMT, DAT1, DRD2, and DRD4 alleles associated with increased reward sensitivity children carried. Maternal negative reactivity and responsiveness were coded during a series of structured mother-child interactions. Executive function was operationalized as self-control and working memory/inhibitory control. Path analysis supported a polygenic composite by negative reactivity interaction for self-control. The nature of the interaction was one of diathesis-stress, such that higher negative reactivity was associated with poorer self-control for children with higher polygenic composite scores. This result suggests that children with a higher number of alleles may be more vulnerable to the negative effect of negative reactivity. Negative reactivity may increase the risk for developing behavior problems in this population via an association with poorer self-control. Due to the small sample size, these initial findings should be treated with caution until they are replicated in a larger independent sample.

Sex Differences in the Behavioural Outcomes of Prenatal Nicotine and Tobacco Exposure

Smoking remains the leading cause of preventable death worldwide. A combination of biological and environmental risk factors make women especially vulnerable to nicotine addiction, making it harder for them to quit smoking. Smoking during pregnancy, therefore, is still a major health concern, with epidemiological data suggesting a role for gestational nicotine exposure in the development of several behavioural disorders. Given there are significant sex-specific behavioural outcomes related to smoking in adolescence and adulthood, it is probable that the behavioural outcomes following gestational nicotine or tobacco exposure are similarly sex-dependent. This is an especially relevant topic as the current landscape of nicotine use shifts toward vaping, a mode of high doses of nicotine delivery that is largely believed to be a safer alternative to cigarettes among the public as well as among pregnant women. Here we review existing clinical and preclinical findings regarding the sex-dependent behavioural outcomes of prenatal nicotine exposure. We also highlight the challenges within this literature, particularly those areas in which further research is necessary to improve consistency within, and between, clinical and preclinical findings.

Impact of prenatal exposure characterization on early risk detection: Methodologic insights for the HEALthy Brain and Child Development (HBCD) study

BACKGROUND

A major challenge in prenatal drug exposure research concerns the balance of measurement quality with sample sizes necessary to address confounders. To inform the selection of optimal exposure measures for the HEALthy Brain and Child Development (HBCD) Study, we employed integrated analysis to determine how different methods used to characterize prenatal tobacco exposure influence the detection of exposure-related risk, as reflected in normal variations in birth weight.

METHODS

Participants were N = 2323 mother-infant dyads derived from 7 independent developmental cohorts harmonized on measures of exposure, outcome (birthweight), and covariates. We compared estimates of PTE-related effects on birthweight derived from linear regression models when PTE was categorized dichotomously based on any fetal exposure (30% exposed; 69% not exposed); versus categorically, based on common patterns of maternal smoking during pregnancy (never smoked 69%; quit smoking 16%; smoked intermittently 2%; smoked persistently 13%). We secondarily explored sex differences in PTE-birthweight associations across these categorization methods.

RESULTS

When PTE was categorized dichotomously, exposure was associated with a - 125-g difference in birthweight (95% C.I. -173.7 - -76.6, p < .0001). When PTE was characterized categorically based on maternal smoking patterns, however, exposure was associated with either no difference in birthweight if mothers quit smoking by the end of the first trimester (B = -30.6, 95% C.I. -88.7-27.4, p = .30); or a - 221.8 g difference in birthweight if mothers did not [95% C.I. (-161.7 to -282.0); p < .001]. Qualitative sex differences were also detected though PTE x sex interactions did not reach statistical significance. Maternal smoking cessation during pregnancy was associated with a 239.3 g increase in birthweight for male infants, and a 114.0 g increase in birthweight for females infants (p = .07).

CONCLUSIONS

Categorization of PTE based on patterns of maternal smoking rather than the presence or absence of exposure alone revealed striking nuances in estimates of exposure-related risk. The described method that captures both between-individual and within-individual variability in prenatal drug exposure is optimal and recommended for future developmental investigations such as the HBCD Study.

Infant neurobehavioural consequences of prenatal cigarette exposure: A systematic review and meta-analysis

AIM

Prenatal exposure to cigarettes leads to alterations in brain development during pregnancy. This has an impact on postnatal psychological and behavioural processes, affecting an infant's neurobehavioural profile with little known about which aspects are affected. The evidence was synthesised to assess the effects of prenatal cigarette smoke exposure on neurobehavioural outcomes within the first year of life.

METHODS

Six databases were searched (Web of Science Core Collections, MEDLINE, PsycINFO, CINAHL, EBSCOhost eBook Collection and OpenGrey) in November 2018. Eligible studies (n = 17) had to include a measure of prenatal cigarette exposure and a neurobehavioural assessment ≤1 year of age.

RESULTS

In the first year of life, specific areas of neurobehavioural functioning are related to prenatal cigarette exposure with eight out of 10 areas of neurobehaviour having significant medium (negative affect, attention, excitability, irritability and orientation) or small (muscle tone, regulation and difficult temperament) pooled effect sizes. Only lethargy and stress did not show any significant pooled effects.

CONCLUSION

Prenatal cigarette exposure affects a significant range of behaviours during the first year of life.

Socioeconomic status and executive function in early childhood: Exploring proximal mechanisms

Although there is substantial evidence that socioeconomic status (SES) predicts children's executive function (EF), the mechanisms underlying this association are poorly understood. This study tested the utility of two theories proposed to link SES to children's EF: the family stress model and the family investment model. Data came from the Midwestern Infant Development Study (N = 151). To measure SES, parental education and income were assessed during pregnancy, and income was also assessed when children were 6 and 36 months old. Children's EF, operationalized as working memory/inhibitory control (WMIC) and self-control, was assessed at 36 months of age, along with potential mediators including maternal psychological distress, harsh parenting, and cognitive stimulation. Using structural equation modeling, we tested simultaneous pathways from SES to EF: (a) via maternal psychological distress to harsh parenting (family stress model) and (b) via cognitive stimulation (family investment model). Of the SES measures, lower education predicted poorer WMIC directly and indirectly via greater maternal psychological distress. Lower education also predicted poorer self-control via greater maternal psychological distress. This effect was partially suppressed by an indirect path from lower education to better self-control via greater psychological distress and increased harsh parenting. Cognitive stimulation did not act as a mediator. Income was not directly or indirectly associated with EF. These findings provide partial support for the family stress model and suggest that family functioning is an important proximal mechanism for children's EF development. This study also highlights the importance of considering SES as a multidimensional construct.

Does early maternal responsiveness buffer prenatal tobacco exposure effects on young children's behavioral disinhibition?

Children with prenatal tobacco exposure (PTE) exhibit early self-regulatory impairments, reflecting a life-course persistent propensity toward behavioral disinhibition. Previously, we demonstrated the protective role of parental responsiveness for reducing the risk of exposure-related disruptive behavior in adolescence. Here, we expanded this line of inquiry, examining whether responsiveness moderates the relation of PTE to a broader set of behavioral disinhibition features in early childhood and testing alternative diathesis-stress versus differential susceptibility explanatory models. PTE was assessed prospectively using interviews and bioassays in the Midwestern Infant Development Study (MIDS). Mother-child dyads (N = 276) were re-assessed at approximately 5 years of age in a preschool follow-up. We quantified maternal responsiveness and child behavioral disinhibition using a combination of directly observed activities in the lab and developmentally sensitive questionnaires. Results supported a diathesis-stress pattern. Children with PTE and less responsive mothers showed increased disruptive behavior and lower effortful control compared with children without PTE. In contrast, exposed children with more responsive mothers had self-regulatory profiles similar to their non-exposed peers. We did not observe sex differences. Findings provide greater specification of the protective role of maternal responsiveness for self-regulation in children with PTE and help clarify mechanisms that may underscore trajectories of exposure-related behavioral disinhibition.

[Current State of Family-Based Prevention and Therapy of Substance-Use Disorders in Children and Adolescents: A Review]

Current State of Family-Based Prevention and Therapy of Substance-Use Disorders in Children and Adolescents: A Review Adolescence is a vulnerable period for substance use disorders (SUD) as indicated by epidemiological studies. Research demonstrates the family's role for the etiology of SUD and provides a rationale for interventions based on family-associated risk and resilience factors. In this article, we summarize published results for family-based interventions from 2008-2018. Taken together, prevention programs can be effective when they focus on the promotion of broader developmental competencies and familial resources, rather than narrowly addressing substance use. Moreover, programs could benefit from targeting youth and parents as done in the "Strengthening Families Program 10-14"; most existing programs however target parents and do not include the adolescents. Family-based treatment programs with an evidence base are Multisystemic Therapy, Functional Family Therapy, Multidimensional Family Therapy and Brief Strategic Family Therapy. Overall, the effects of family-based interventions are small-to-middle sized but vary significantly across populations. Across the field of family-based interventions, there is a need for more knowledge on effective components and differential effects. The results could be improved by translational research such as on the emerging concept of mindfulness. Moreover, there is a need for implementation research and the effectiveness of service delivery programs on the community level in Germany.

Mindfulness-based Stress Reduction in Pregnancy: an App-Based Programme to Improve the Health of Mothers and Children (MINDFUL/PMI Study)

Unfavourable intrauterine environmental factors increase the risk of delivery complications as well as postpartum developmental and behavioural problems in children and adolescents with ongoing effects into older age. Biomarker studies show that maternal stress and the use of alcohol and tobacco during pregnancy are associated with a higher intrauterine testosterone exposure of the child. The antenatal testosterone load, in turn, is a risk factor for lasting adverse health effects which extend into adulthood. A 15-week, mindfulness-oriented, app-based programme for the reduction of stress as well as for the reduction of alcohol and tobacco use in pregnant women is established. In the monocentre, prospective, controlled, and investigator-blinded MINDFUL/PMI (Maternal Health and Infant Development in the Follow-up after Pregnancy and a Mindfulness Intervention) study, pregnant women carry out the programme. Its effect on antenatal testosterone exposure of the child is examined by assessing the index/ring finger length ratio and other biomarkers in the 1-year-old children. In addition, the programmeʼs effects on self-regulation, the developmental status and the mental health of the children at the age of one year will be investigated. Additional aspects of the course of the pregnancy and delivery represent exploratory study objectives. This longitudinal study project is intended to improve the understanding of the impact of intrauterine environmental factors on early childhood development and health. Maternal stress as well as alcohol and tobacco use during pregnancy are modifiable factors and represent potential preventive targets.

[Prevention of substance use disorders]

Prevention of substance use disorders Abstract. Introduction: Adolescence is a vulnerable period for the development of Substance Use Disorders and preventive intervention is a public health priority. In this article, we summarize the available evidence for behavioral preventive action for Substance Use Disorders and related dysregulated behaviors during adolescence in various settings. Results: Current meta-analytic evidence is available mainly for the school and family settings and increasingly also for internet-based prevention. The literature is dominated by US-studies that focus on universal school-based approaches for legal substances in middle adolescence. Only few German studies are published. Taken together the results indicate that developmentally sensitive substance use prevention is effective across different settings with consistent small-to-middle sized effects. Differential effectiveness analyses for schoolbased prevention suggest that younger adolescents benefit most from universal prevention, while for older adolescents targeted approaches are more effective. Conclusions: Across the relevant settings, effective preventive measures are available. However, the results could be improved. There is a need for translational research on effective and more individualized approaches to prevention and differential effects of intervention modules. Moreover, there is a need for research on the implementation of evidence-based programs and especially in Germany, coordinated approaches on community levels are lacking.

Maternal smoking during pregnancy and offspring executive function: What do we know and what are the next steps?

Children exposed to maternal smoking during pregnancy (MSDP) exhibit difficulties in executive function (EF) from infancy through adolescence. Due to the developmental significance of EF as a predictor of adaptive functioning throughout the life span, the MSDP-EF relation has clear public health implications. In this paper, we provide a comprehensive review of the literature on the relationship between MSDP and offspring EF across development; consider brain-based assessments, animal models, and genetically informed studies in an effort to elucidate plausible pathways of effects; discuss implications for prevention and intervention; and make calls to action for future research.

Prenatal exposure to tobacco and cannabis: Effects on autonomic and emotion regulation

Tobacco and cannabis are often used together in pregnancy and both have effects on children's regulatory system. Yet, little is known about the impact of co-use on the development of emotion regulation at the developmentally salient age of 2 years. One pathway linking co-exposure to tobacco and cannabis to toddler regulation may be via poor autonomic regulation in infancy. In addition, substance using mothers may be more dysregulated themselves, which may have direct effects on toddler regulation, but may also affect parenting, particularly maternal sensitivity during mother-child interactions. Thus, a second pathway linking exposure to toddler regulation may be via maternal dysregulation and low maternal sensitivity. We examined a conceptual model linking prenatal exposure to toddler regulation via these two pathways in a prospective sample (N = 247) of mother-child dyads recruited in the first trimester of pregnancy. Results indicated significant effects of co-exposure on poor autonomic regulation in infancy, which in turn predicted poor toddler emotion regulation. Mothers who used both tobacco and cannabis displayed lower sensitivity during play interactions with their infants. Maternal sensitivity was modestly stable from infant to toddler period and was predictive of higher toddler emotion regulation. Continued postnatal exposure to tobacco was also a significant, unique predictor of lower toddler emotion regulation. Results highlight the importance of examining co-exposure effects and suggest that this common pattern of use may be associated with higher infant/toddler risks.

Intrauterine exposure to tobacco and executive functioning in high school

BACKGROUND

Executive functioning (EF), an umbrella construct encompassing gradual maturation of cognitive organization/management processes, is important to success in multiple settings including high school. Intrauterine tobacco exposure (IUTE) correlates with negative cognitive/behavioral outcomes, but little is known about its association with adolescent EF and information from real-life contexts is sparse. We evaluated the impact of IUTE on teacher-reported observations of EF in urban high school students controlling for covariates including other intrauterine and adolescent substance exposures.

METHODS

A prospective low-income birth cohort (51% male; 89% African American/Caribbean) was followed through late adolescence (16-18 years old). At birth, intrauterine exposures to cocaine and other substances (52% cocaine, 52% tobacco, 26% marijuana, 26% alcohol) were identified by meconium and/or urine assays, and/or maternal self-report. High school teachers knowledgeable about the student and unaware of study aims were asked to complete the Behavior Rating Inventory of Executive Functioning-Teacher Form (BRIEF-TF) annually.

RESULTS

Teachers completed at least one BRIEF-TF for 131 adolescents. Multivariable analyses included controls for: demographics; intrauterine cocaine, marijuana, and alcohol exposures; early childhood exposures to lead; and violence exposure from school-age to adolescence. IUTE was associated with less optimal BRIEF-TF Behavioral Regulation scores (p <0.05). Other intrauterine substance exposures did not predict less optimal BRIEF-TF scores, nor did exposures to violence, lead, nor adolescents' own substance use.

CONCLUSIONS

IUTE is associated with offspring's less optimal EF. Prenatal counseling should emphasize abstinence from tobacco, as well as alcohol and illegal substances.

Prenatal tobacco exposure and self-regulation in early childhood: Implications for developmental psychopathology

Prenatal tobacco exposure (PTE) has a well-documented association with disruptive behavior in childhood, but the neurocognitive effects of exposure that underlie this link are not sufficiently understood. The present study was designed to address this gap, through longitudinal follow-up in early childhood of a prospectively enrolled cohort with well-characterized prenatal exposure. Three-year-old children (n = 151) were assessed using a developmentally sensitive battery capturing both cognitive and motivational aspects of self-regulation. PTE was related to motivational self-regulation, where children had to delay approach to attractive rewards, but not cognitive self-regulation, where children had to hold information in mind and inhibit prepotent motor responses. Furthermore, PTE predicted motivational self-regulation more strongly in boys than in girls, and when propensity scores were covaried to control for confounding risk factors, the effect of PTE on motivational self-regulation was significant only in boys. These findings suggest that PTE's impact on neurodevelopment may be greater in boys than in girls, perhaps reflecting vulnerability in neural circuits that subserve reward sensitivity and emotion regulation, and may also help to explain why PTE is more consistently related to disruptive behavior disorders than attention problems.

Testing the Developmental Origins of Health and Disease Hypothesis for Psychopathology Using Family-Based Quasi-Experimental Designs

The Developmental Origin of Health and Disease (DOHaD) hypothesis is a broad theoretical framework that emphasizes how early risk factors have a causal influence on psychopathology. Researchers have raised concerns about the causal interpretation of statistical associations between early risk factors and later psychopathology because most existing studies have been unable to rule out the possibility of environmental and genetic confounding. In this paper we illustrate how family-based quasi-experimental designs can test the DOHaD hypothesis by ruling out alternative hypotheses. We review the logic underlying sibling-comparison, co-twin control, offspring of siblings/twins, adoption, and in vitro fertilization designs. We then present results from studies using these designs focused on broad indices of fetal development (low birth weight and gestational age) and a particular teratogen, smoking during pregnancy. The results provide mixed support for the DOHaD hypothesis for psychopathology, illustrating the critical need to use design features that rule out unmeasured confounding.