Prenatal maternal smoking, maternal offending, and offspring behavioural and cognitive outcomes in early childhood

Predicting child development and school readiness, at age 5, for Aboriginal and non-Aboriginal children in Australia's Northern Territory

BACKGROUND

Positive early development is critical in shaping children's lifelong health and wellbeing. Identifying children at risk of poor development is important in targeting early interventions to children and families most in need of support. We aimed to develop a predictive model that could inform early support for vulnerable children.

METHODS

We analysed linked administrative records for a birth cohort of 2,380 Northern Territory children (including 1,222 Aboriginal children) who were in their first year of school in 2015 and had a completed record from the Australian Early Development Census (AEDC). The AEDC measures early child development (school readiness) across five domains of development. We fitted prediction models, for AEDC weighted summary scores, using a Partial Least Square Structural Equation Model (PLS-SEM) considering four groups of factors-pre-pregnancy, pregnancy, known at birth, and child-related factors. We first assessed the models' internal validity and then the out-of-sample predictive power (external validity) using the PLSpredict procedure.

RESULT

We identified separate predictive models, with a good fit, for Aboriginal and non-Aboriginal children. For Aboriginal children, a significant pre-pregnancy predictor of better outcomes was higher socioeconomic status (direct, β = 0.22 and indirect, β = 0.16). Pregnancy factors (gestational diabetes and maternal smoking (indirect, β = -0.09) and child-related factors (English as a second language and not attending preschool (direct, β = -0.28) predicted poorer outcomes. Further, pregnancy and child-related factors partially mediated the effects of pre-pregnancy factors; and child-related factors fully mediated the effects of pregnancy factors on AEDC weighted scores. For non-Aboriginal children, pre-pregnancy factors (increasing maternal age, socioeconomic status, parity, and occupation of the primary carer) directly predicted better outcomes (β = 0.29). A technical observation was that variance in AEDC weighted scores was not equally captured across all five AEDC domains; for Aboriginal children results were based on only three domains (emotional maturity; social competence, and language and cognitive skills (school-based)) and for non-Aboriginal children, on a single domain (language and cognitive skills (school-based)).

CONCLUSION

The models give insight into the interplay of multiple factors at different stages of a child's development and inform service and policy responses. Recruiting children and their families for early support programs should consider both the direct effects of the predictors and their interactions. The content and application of the AEDC measurement need to be strengthened to ensure all domains of a child's development are captured equally.

The correlation between prenatal maternal active smoking and neurodevelopmental disorders in children: a systematic review and meta-analysis

OBJECTIVE

To systematically evaluate the association between maternal active smoking during pregnancy and Tourette syndrome (TS), chronic tic disorder (CTD), and developmental coordination disorder (DCD) in children, and to provide evidence-based medical references to reduce the incidence of neurodevelopmental disorders in children.

METHOD

We searched PubMed, Web of Science, Embase, and Cochrane Library to obtain relevant articles published before 4 August 2021. Two reviewers independently assessed the articles for eligibility and extracted data.

RESULTS

We included eight studies involving a total of 50,317 participants (3 cohort, 3 case-control, and 2 cross-sectional studies). The pooled effect estimates suggested that prenatal maternal active smoking is related to an increased risk of neurodevelopmental disorders (OR = 1.91, 95% CI: 1.30-2.80), especially DCD (OR = 2.25, 95% CI: 1.35-3.75). Maternal active smoking during pregnancy is not associated with TS (OR = 1.07, 95% CI: 0.66-1.73) in children.

CONCLUSION

In this meta-analysis, we found evidence for a correlation between active smoking exposure in pregnant women and neurodevelopmental disorders in children. Owing to the differences in sample size, smoking categories and diagnostic methods, further research is needed to validate our results.

Average treatment effect of maternal prenatal tobacco smoking on offspring developmental vulnerability in early childhood

BACKGROUND

Early childhood developmental vulnerability has been closely related to the predictors of relatively good health, social and educational outcomes later in adulthood. However, the impacts of prenatal tobacco exposure on childhood developmental vulnerability have been rarely examined. Further, a few of the studies that have investigated maternal prenatal tobacco smoking and child developmental vulnerability have reported mixed results and there are currently no published estimates derived from causal epidemiological methods.

METHODS

We conducted a retrospective population-based cohort study on the association between maternal prenatal tobacco smoking and developmental vulnerability in children born in Western Australia (WA). De-identified individual-level maternal, infant and birth records were obtained from the Midwives Notification System (MNS), a statutory record of all births in WA. WA register for Developmental Anomalies (WARDA) were also obtained from the WA Data Linkage. Records on early childhood developmental vulnerability at the median age of 5 years were obtained from the Australian Early Development Census (AEDC). We used a doubly robust estimator to estimate the causal effects.

RESULTS

Complete data were available for 64,558 mothers-children's pairs. Approximately 16% of children were exposed to maternal prenatal tobacco smoking. Children exposed to maternal prenatal tobacco smoking were more likely to be classified as developmentally vulnerable/at-risk on the physical health and wellbeing (RR = 1.40, 95%CI:1.36-1.45), social competence (RR = 1.42, 95%CI: 1.38-1.47), emotional maturity (RR = 1.34, 95%CI:1.30-1.39), language and cognitive skills (RR = 1.50, 95%CI:1.45-1.54), and communication skills and general knowledge (RR = 1.37, 95%CI:1.33-1.42) domains.

CONCLUSION

Maternal prenatal exposure to tobacco may influence early childhood developmental vulnerability. Early intervention to quit tobacco smoking before becoming pregnant could potentially reduce later childhood developmental vulnerability on multiple domains.

Risk factors for developmental vulnerability: Insight from population-level surveillance using the Early Development Instrument

Objectives

Population-level studies may elucidate the most promising intervention targets to prevent negative outcomes of developmental vulnerability in children. This study aims to bridge the current literature gap on identifying population-level developmental vulnerability risk factors using combined social and biological/health information.

Methods

This study assessed developmental vulnerability among kindergarten children using the 2016 Early Development Instrument (EDI) and identified risk factors of developmental vulnerability using EDI data cross-linked to a population-wide administrative health dataset. A total number of 23,494 children aged 5-6 were included (48% female). Prenatal, neonatal, and early childhood risk factors for developmental vulnerability were investigated, highlighting the most important ones contributing to early development.

Results

The main risk factors for developmental vulnerability were children with a history of mental health diagnosis (risk ratio  = 1.46), biological sex-male (risk ratio =  1.51), and poor socioeconomic status (risk ratio =  1.58).

Conclusion

Our study encompasses both social and health information in a populational-level representative sample of Alberta, Canada. The results confirm evidence established in other geographic regions and jurisdictions and demonstrate the association between perinatal risk factors and developmental vulnerability. Based on these results, we argue that the health system should adopt a multilevel prevention and intervention strategy, targeting individual, family, and community together.

Central Australian Aboriginal women's placental and neonatal outcomes following maternal smokeless tobacco, cigarette or no tobacco use

OBJECTIVE

To describe the placental characteristics and neonatal outcomes of Central Australian Aboriginal women based on maternal self-report of tobacco use.

METHODS

Placental and neonatal variables were collected from a prospective maternal cohort of 19 smokeless tobacco chewers, 23 smokers and 31 no-tobacco users.

RESULTS

Chewers had the lowest placental weight (460 g) while the no-tobacco group had the heaviest placental weight (565 g). Chewers and the no-tobacco group had placental areas of similar size (285 cm² and 288 cm² , respectively) while the placentas of smokers were at least 13 cm² smaller (272 cm² ). There were two stillbirths in the study and more than one-third (36%) of neonates (newborns) were admitted to the Special Care Nursery, with the chewers' neonates having a higher admission rate compared with smokers' neonates (44% vs. 23%). The cohort mean birthweight (3348 g) was not significantly different between the groups. When stratified for elevated maternal glucose, the chewers' neonates had the lowest mean birthweight (2906 g) compared to the neonates of the no-tobacco group (3242 g) and smokers (3398 g).

CONCLUSIONS

This research is the first to demonstrate that the maternal use of Australian Nicotiana spp. (pituri) as smokeless tobacco may negatively impact placental and neonatal outcomes. Implications for public health: Maternal smokeless tobacco use is a potential source of placental and foetal nicotine exposure. Maternal antenatal screening should be expanded to capture a broader range of tobacco and nicotine products, and appropriate cessation support is required.

Microbiome profiles are associated with cognitive functioning in 45-month-old children

Prenatal, perinatal, and postnatal factors have been shown to shape neurobiological functioning and alter the risk for mental disorders later in life. The gut microbiome is established early in life, and interacts with the brain via the brain-immune-gut axis. However, little is known about how the microbiome relates to early-life cognitive functioning in children. The present study, where the fecal microbiome of 380 children was characterized using 16S rDNA and metagenomic sequencing aimed to investigate the association between the microbiota and cognitive functioning of children at the age of 45 months measured with the Wechsler Preschool and Primary Scale of Intelligence (WPPSI-III). Overall the microbiome profile showed a significant association with cognitive functioning. A strong correlation was found between cognitive functioning and the relative abundance of an unidentified genus of the family Enterobacteriaceae. Follow-up mediation analyses revealed significant mediation effects of the level of this genus on the association of maternal smoking during pregnancy and current cigarette smoking with cognitive function. Metagenomic sequencing of a subset of these samples indicated that the identified genus was most closely related to Enterobacter asburiae. Analysis of metabolic potential showed a nominally significant association of cognitive functioning with the microbial norspermidine biosynthesis pathway. Our results indicate that alteration of the gut microflora is associated with cognitive functioning in childhood. Furthermore, they suggest that the altered microflora might interact with other environmental factors such as maternal cigarette smoking. Interventions directed at altering the microbiome should be explored in terms of improving cognitive functioning in young children.

What lessons have we learnt about the impact of maternal cigarette smoking from animal models?

Maternal first- or second-hand tobacco smoking during pregnancy is still common albeit that the detrimental effects to the unborn child are well known. Maternal tobacco cigarette smoking can affect multiple organ systems in the offspring, rendering them at increased risk of various conditions throughout life (eg. intrauterine underdevelopment, asthma, substance abuse, diabetes). However, this review will only focus on its impact on the brain and the related molecular changes in the offspring based on evidence from animal studies. Although epidemiological studies have identified the associations between maternal cigarette smoke exposure (SE) and brain disorders, animal models can help identify the underlying mechanisms and test interventions. Human studies have found that maternal SE is closely linked to small brain size and changes in brain structure and associated with a high risk of cognitive defects. Animal models suggest that this may be due to increased brain oxidative stress and inflammation during the neonatal period, leading to increased brain cell apoptosis in adulthood. There is a distinct gender bias of such impacts, where male offspring are more affected than females. Female offspring seem to have developed the adaptation by increasing endogenous antioxidant levels. Indeed, animal studies have shown that using antioxidant supplementation during pregnancy can improve neurological outcomes in male offspring, however, the efficacy in humans is yet to be confirmed. Furthermore, some animal studies suggested nicotine as the key player in intrauterine underdevelopment due to maternal SE, while human clinical trials using nicotine replacement therapy do not support this mechanism. This review will discuss the possible reasons.

The influence of parental offending on the continuity and discontinuity of children's internalizing and externalizing difficulties from early to middle childhood

PURPOSE

Although parental criminal offending is a recognized risk factor for conduct problems among offspring, its impact on the continuity and discontinuity of children's behavioural and emotional difficulties during the early development is less well known. We used data from a large, population-based record-linkage project to examine the relationship between parental offending and the continuity and discontinuity of children's conduct, attentional, and emotional difficulties from early to middle childhood while also considering the role of timing of the parental offending exposure.

METHOD

Data for 19,208 children and their parents were drawn from the New South Wales Child Development Study. Multinomial regression analyses tested associations between mother's and father's history and timing of any and violent offending, and patterns of continuity or discontinuity in offspring emotional, conduct, and attentional difficulties between ages 5 and 11 years.

RESULTS

Maternal and paternal offending each conferred a significantly increased risk of all the patterns of developmental difficulties, including those limited to age 5 only (remitting problems), to age 11 only (incident problems), and to difficulties present at both ages 5 and 11 years (persisting problems). Greatest odds were observed for persisting conduct problems. Paternal offending that continued through early and middle childhood had the greatest association with child difficulties, while the timing of maternal offending had a less prominent effect on child developmental difficulties.

CONCLUSION

Parental offending is a strong risk factor for early and pervasive behavioural and emotional problems in offspring, and may be a key indicator of high risk for later antisocial behaviour.