The impact of maternal smoking during pregnancy on depressive and anxiety behaviors in children: the Norwegian Mother and Child Cohort Study

Perinatal and neonatal factors and mental disorders in children and adolescents: looking for the contributions of the early environment to common and dissociable aspects of psychopathology

High rates of co-occurrence of mental disorders have been hypothesized to represent a result of common susceptibility to overall psychopathology. The purpose of this study is to test the hypothesis that commonalities among psychiatric disorders might be partially driven by sharable perinatal and neonatal environmental factors for mental disorders. Participants were 6-14 years of age children and their parents. Primary caregivers provided data on perinatal and neonatal information assessed retrospectively (n = 2231). Psychiatric disorders diagnoses were assessed using the Development and Well Being Behavior Assessment (DAWBA). We used bifactor models to disentangle common from dissociable aspects of psychopathology. These models allow modeling psychiatric disorders as the result of a common domain of psychopathology (p-factor) and three dissociable domains (fear, distress, and externalizing symptoms). Associations were tested using linear and tobit regression models. The p-factor was associated with male sex, low socioeconomic status, gestational smoking, gestational drinking, low levels of maternal education and presence of mental disorder in the mother. Associations with specific factors also emerged suggesting some risk factors might also have some role for fear, distress and externalizing factors. Our study supports the hypothesis that overall susceptibility to psychopathology might be partially driven by sharable perinatal and neonatal factors.

Multiple Risk in Pregnancy- Prenatal Risk Constellations and Mother-Infant Interactions, Parenting Stress, and Child Externalizing and Internalizing Behaviors: A Prospective Longitudinal Cohort Study from Pregnancy to 18 Months Postpartum

Multiple risk is associated with adverse developmental outcomes across domains. However, as risk factors tend to cluster, it is important to investigate formation of risk constellations, and how they relate to child and parental outcomes. By means of latent class analysis patterns of prenatal risk factors were identified, and relations to interactional quality, parenting stress, and child internalizing and externalizing behaviors were investigated. An array of prenatal risk factors was assessed in 1036 Norwegian pregnant women participating in a prospective longitudinal community-based study, Little in Norway. Mother-infant interactions were videotaped and scored with the Early Relational Health Screen (ERHS) at 12 months. The Parenting Stress Index (PSI) and Infant-Toddler Social and Emotional Assessment (ITSEA) were administered at 18 months. First, we analyzed response patterns to prenatal risks to identify number and characteristics of latent classes. Second, we investigated whether latent class membership could predict mother-child interactional quality, parenting stress, and child internalizing and externalizing behavior after the child was born. Results revealed three prenatal risk constellations: broad risk (7.52%), mental health risk (21.62%) and low-risk (70.86%). Membership in the broad risk group predicted lower scores on interactional quality, while membership in the mental health risk group predicted less favorable scores on all outcome measures. Prenatal risks clustered together in specific risk constellations that differentially related to parent, child and interactional outcomes.

Utility of the Zebrafish Model for Studying Neuronal and Behavioral Disturbances Induced by Embryonic Exposure to Alcohol, Nicotine, and Cannabis

It is estimated that 5% of pregnant women consume drugs of abuse during pregnancy. Clinical research suggests that intake of drugs during pregnancy, such as alcohol, nicotine and cannabis, disturbs the development of neuronal systems in the offspring, in association with behavioral disturbances early in life and an increased risk of developing drug use disorders. After briefly summarizing evidence in rodents, this review focuses on the zebrafish model and its inherent advantages for studying the effects of embryonic exposure to drugs of abuse on behavioral and neuronal development, with an emphasis on neuropeptides known to promote drug-related behaviors. In addition to stimulating the expression and density of peptide neurons, as in rodents, zebrafish studies demonstrate that embryonic drug exposure has marked effects on the migration, morphology, projections, anatomical location, and peptide co-expression of these neurons. We also describe studies using advanced methodologies that can be applied in vivo in zebrafish: first, to demonstrate a causal relationship between the drug-induced neuronal and behavioral disturbances and second, to discover underlying molecular mechanisms that mediate these effects. The zebrafish model has great potential for providing important information regarding the development of novel and efficacious therapies for ameliorating the effects of early drug exposure.

Maternal adherence to healthy lifestyle and risk of depressive symptoms in the offspring: mediation by offspring lifestyle

BACKGROUND

Adherence to healthy lifestyles can be beneficial for depression among adults, but the intergenerational impact of maternal healthy lifestyles on offspring depressive symptoms is unknown.

METHODS

In total, 10 368 mothers in Nurses' Health Study II and 13 478 offspring in the Growing Up Today Study were paired. Maternal and offspring healthy lifestyles were defined as a composite score including a healthy diet, normal body mass index (BMI), never-smoking, light-to-moderate consumption of alcohol, and regular moderate-to-vigorous physical activity. Maternal lifestyles were assessed during their offspring's childhood. Offspring depressive symptoms were repeatedly assessed five times using the Center for Epidemiological Studies Depression Scale-10 (CESD-10); the offspring were between the ages of 14 and 30 when the first CESD-10 was assessed. Covariates included maternal variables (age at baseline, race/ethnicity, antidepressant use, pregnancy complications, etc.) and offspring age and sex.

RESULTS

Children of mothers with the healthiest lifestyle had significantly fewer depressive symptoms (a 0.30 lower CESD-10 score, 95% confidence interval (CI) 0.09-0.50) in comparison with children of mothers with the least healthy lifestyle. The association was only found significant in female offspring but not in males. For individual maternal lifestyle factors, a normal BMI, never-smoking, and adherence to regular physical activity were independently associated with fewer depressive symptoms among the offspring. The association between maternal healthy lifestyles and offspring depressive symptoms was mediated by offspring's healthy lifestyles (mediation effect: 53.2%, 95% CI 15.8-87.3).

CONCLUSIONS

Our finding indicates the potential mechanism of intergenerational transmission of healthy lifestyles to reduce the risk of depressive symptoms in offspring.

Maternal oxidative stress during pregnancy associated with emotional and behavioural problems in early childhood: implications for foetal programming

Childhood mental disorders, including emotional and behavioural problems (EBP) are increasingly prevalent. Higher maternal oxidative stress (OS) during pregnancy (matOSpreg) is linked to offspring mental disorders. Environmental factors contribute to matOSpreg. However, the role of matOSpreg in childhood EBP is unclear. We investigated the associations between (i) matOSpreg and offspring EBP; (ii) social and prenatal environmental factors and matOSpreg; and (iii) social and prenatal factors and childhood EBP and evaluated whether matOSpreg mediated these associations. Maternal urinary OS biomarkers, 8-hydroxyguanosine (8-OHGua; an oxidative RNA damage marker) and 8-hydroxy-2'-deoxyguanosine (8-OHdG; an oxidative DNA damage marker), at 36 weeks of pregnancy were quantified by liquid chromatography-mass spectrometry in a population-derived birth cohort, Barwon Infant Study (n = 1074 mother-infant pairs). Social and prenatal environmental factors were collected by mother-reported questionnaires. Offspring total EBP was measured by Child Behavior Checklist Total Problems T-scores at age two (n = 675) and Strengths and Difficulties Questionnaire Total Difficulties score at age four (n = 791). Prospective associations were examined by multivariable regression analyses adjusted for covariates. Mediation effects were evaluated using counterfactual-based mediation analysis. Higher maternal urinary 8-OHGua at 36 weeks (mat8-OHGua36w) was associated with greater offspring total EBP at age four (β = 0.38, 95% CI (0.07, 0.69), P = 0.02) and age two (β = 0.62, 95% CI (-0.06, 1.30), P = 0.07). Weaker evidence of association was detected for 8-OHdG. Five early-life factors were associated with both mat8-OHGua36w and childhood EBP (P-range < 0.001-0.05), including lower maternal education, socioeconomic disadvantage and prenatal tobacco smoking. These risk factor-childhood EBP associations were partly mediated by higher mat8-OHGua36w (P-range = 0.01-0.05). Higher matOSpreg, particularly oxidant RNA damage, is associated with later offspring EBP. Effects of some social and prenatal lifestyle factors on childhood EBP were partly mediated by matOSpreg. Future studies are warranted to further elucidate the role of early-life oxidant damage in childhood EBP.

Prenatal nicotine exposure during pregnancy results in adverse neurodevelopmental alterations and neurobehavioral deficits

Maternal tobacco use and nicotine exposure during pregnancy have been associated with adverse birth outcomes in infants and can lead to preventable pregnancy complications. Exposure to nicotine and other compounds in tobacco and electronic cigarettes (e-cigarettes) has been shown to increases the risk of miscarriage, prematurity, stillbirth, low birth weight, perinatal morbidity, and sudden infant death syndrome (SIDS). Additionally, recent data provided by clinical and pre-clinical research demonstrates that nicotine exposure during pregnancy may heighten the risk for adverse neurodevelopmental disorders such as Attention-Deficit Hyperactivity (ADHD), anxiety, and depression along with altering the infants underlying brain circuitry, response to neurotransmitters, and brain volume. In the United States, one in 14 women (7.2%) reported to have smoked cigarettes during their pregnancy with the global prevalence of smoking during pregnancy estimated to be 1.7%. Approximately 1.1% of women in the United States also reported to have used e-cigarettes during the last 3 months of pregnancy. Due to the large percentage of women utilizing nicotine products during pregnancy in the United States and globally, this review seeks to centralize pre-clinical and clinical studies focused on the neurobehavioral and neurodevelopmental complications associated with prenatal nicotine exposure (PNE) such as alterations to the hypothalamic-pituitary-adrenal (HPA) axis and brain regions such as the prefrontal cortex (PFC), ventral tegmental area (VTA), nucleus accumbens (NA), hippocampus, and caudate as well as changes to nAChR and cholinergic receptor signaling, long-term drug seeking behavior following PNE, and other related developmental disorders. Current literature analyzing the association between PNE and the risk for offspring developing schizophrenia, attention-deficit hyperactivity disorder (ADHD), autism spectrum disorder (ASD), anxiety, and obesity will also be discussed.

Association of Maternal Smoking during Pregnancy with Neurophysiological and ADHD-Related Outcomes in School-Aged Children

Data of a longitudinal cohort study were analyzed to investigate the association between prenatal tobacco exposure and electroencephalographical (EEG) power spectrum in healthy, school-aged children as well as its relationship with attention deficit hyperactivity disorder (ADHD)-related symptoms. Group comparisons (exposed, non-exposed) were performed to test whether prenatal tobacco exposure was associated with brain activity and ADHD symptoms, with adjustments made for covariates including child's sex, child's age, maternal age, maternal smoking habit before pregnancy, alcohol consumption during pregnancy, gestation age, and maternal psychopathology. Tobacco-exposed children showed higher brain activity in the delta and theta frequency bands. This effect was independent of the considered covariates. However, the effects on hyperactivity were found to significantly depend on maternal age and alcohol consumption during pregnancy, but not on the amount of exposure. In summary, smoking during pregnancy significantly affected the resting-state brain activity in children, independent of socio-demographic factors, indicating potential long-lasting effects on brain development. Its impact on ADHD-related behavior was shown to be influenced by socio-demographic confounding factors, such as maternal alcohol consumption and the age of the mother.

Maternal smoking during pregnancy, offspring smoking, adverse childhood events, and risk of major depression: a sibling design study

BACKGROUND

Evidence of a biologically plausible association between maternal smoking during pregnancy (MSP) and the risk of depression is discounted by null findings from two sibling studies. However, valid causal inference from sibling studies is subject to challenges inherent to human studies of MSP and biases particular to this design. We addressed these challenges in the first sibling study of MSP and depression conducted among adults past the peak age for the onset of depression, utilizing a prospectively collected and biologically validated measure of MSP and accounting for non-shared as well as mediating factors.

METHODS

We fit GEE binomial regression models to correct for dependence in the risk of depression across pregnancies of the same mother. We also fit marginal structural models (MSM) to estimate the controlled direct effect of MSP on depression that is not mediated by the offspring's smoking status. Both models allow the estimation of within- and between-sibling risk ratios.

RESULTS

The adjusted within-sibling risk ratios (RR_W) from both models (GEE: RR_W = 1.97, CI 1.16-3.32; MSM: RR_W = 2.08, CI 1.04-4.17) evinced an independent association between MSP and risk of depression. The overall effects from a standard model evinced lower associations (GEE: RR_T = 1.12, CI 0.98-1.28; MSM: RR_T = 1.18, CI 1.01-1.37).

CONCLUSIONS

Based on within-sibling information free of unmeasured shared confounders and accounting for a range of unshared factors, we found an effect of MSP on the offspring's risk of depression. Our findings, should they be replicated in future studies, highlight the importance of considering challenges inherent to human studies of MSP and affective disorders.

Infant inflammation predicts childhood emotional and behavioral problems and partially mediates socioeconomic disadvantage

BACKGROUND

Emotional and behavioral problems (EBP) are common in children. Environmental factors like socioeconomic disadvantage influence EBP pathogenesis and can trigger inflammation. However, the link between early inflammation-EBP in children is unclear. We investigated the associations between i) infant inflammatory biomarkers and subsequent EBP and ii) early life environmental factors and EBP and assessed whether infant inflammation mediated these associations.

METHODS

Inflammatory biomarkers glycoprotein acetyls (GlycA) and high-sensitivity C-reactive protein (hsCRP) were quantified at birth and 12 months in a population-derived birth cohort, the Barwon Infant Study. Early life factors including demographic, prenatal, and perinatal factors were collected from antenatal to the two-year period. Internalizing and externalizing problems at age two were measured by the Child Behavior Checklist. Prospective associations were examined by multivariable regression analyses adjusted for potential confounders. Indirect effects of early life factors on EBP through inflammation were identified using mediation analyses.

RESULTS

Elevated GlycA levels at birth (GlycAbirth) were associated with greater internalizing problems at age two (β = 1.32 per SD increase in GlycA; P = 0.001). Inflammation at birth had a stronger magnitude of effect with later EBP than at 12 months. GlycAbirth partially mediated the associations between lower household income (6%), multiparity (12%) and greater number of older siblings (13%) and EBP. Patterns were less evident for hsCRP or externalizing problems.

CONCLUSIONS

GlycAbirth was positively associated with EBP at age two and partially mediated the association between several indicators of socioeconomic disadvantage and EBP. Prenatal and perinatal inflammation may be relevant to early neurodevelopment and emotional health.

Prenatal determinants of depressive symptoms in childhood: Evidence from Growing Up in New Zealand

BACKGROUND

Young people who experience depression are at an increased risk of adverse psychosocial and developmental outcomes that can persist over the lifecourse. Identifying maternal prenatal risk factors that may contribute to childhood depressive symptoms can be useful when considering mental health intervention.

METHODS

The current study included 3,925 children from the Growing Up in New Zealand (GUiNZ) study who had complete data for self-reported depressive symptoms and mothers' antenatal information. Depressive symptoms were measured at age 8 using the Centre for Epidemiological Studies Depression Scale for Children (CESD-10) short form questionnaire. Hierarchical linear regression was used to determine the relationship between prenatal factors and depressive symptoms at age 8.

RESULTS

When controlling for sociodemographic characteristics, our hierarchical linear regression revealed that the most significant maternal prenatal predictors of high depressive symptoms at age 8 were maternal perceived stress, smoking during pregnancy, body mass index (BMI) in the overweight/obese range, and paracetamol intake.

LIMITATIONS

One limitation with the current study was a reduction in the sample due to attrition. This may have affected our statistical power, reflected in our modest effect sizes. The sample remained both socioeconomically and ethnically diverse, however our results should be interpreted with respect to the sample and not the whole New Zealand population.

CONCLUSIONS

A combination of maternal mental health and lifestyle factors contribute to depressive symptoms for children, possibly through foetal programming. Our results emphasise the importance of mental and physical health support for expectant mothers.

Prenatal tobacco and alcohol exposures and the risk of anxiety symptoms in young adulthood: A population-based cohort study

BACKGROUND

Epidemiological studies have linked prenatal tobacco and alcohol exposures to internalizing behaviours in children and adolescents with inconsistent findings. Dearth of epidemiological studies have investigated the associations with the risk of experiencing symptoms of anxiety in young adulthood.

METHODS

Study participants (N = 1190) were from the Raine Study, a population-based prospective birth cohort based in Perth, Western Australia. Data on prenatal tobacco and alcohol exposures were available for the first and third trimesters of pregnancy. Experiencing symptoms of anxiety in young adulthood at age 20 years was measured by a short form of the Depression Anxiety Stress Scale (DASS 21). Relative risk (RR) of experiencing symptoms of anxiety in young adulthood for prenatal tobacco and alcohol exposures were estimated with log binomial regression.

RESULTS

After adjusting for potential confounders, we observed increased risks of experiencing symptoms of anxiety in young adults exposed to prenatal tobacco in the first trimester [RR = 1.52, 95% CI: 1.12-2.06, p-value < 0.01] and third trimester [RR = 1.53, 95% CI: 1.10-2.13, p-value  = 0.02]. However, we found insufficient statistical evidence for an association between first trimester [RR = 1.01, 95% CI: 0.76-1.22, p-value = 0.90] and third trimester [RR = 1.03, 95% CI: 0.80-1.34, p-value = 0.91] prenatal exposure to alcohol and the risk of experiencing symptoms of anxiety in young adults. There was a dose response association between prenatal tobacco exposure and increasing anxiety symptoms in offspring.

CONCLUSION

The findings of this study suggest that an association between prenatal tobacco exposure and risk of anxiety symptoms remains apparent into young adulthood.

Maternal smoking during pregnancy and intelligence quotient of offspring aged 18 and 30 years: Evidence from two birth cohorts in southern Brazil

Maternal smoking during pregnancy causes several harmful effects, including deficits in the intelligence quotient (IQ), a measure associated with academic achievements and higher socioeconomic position. We aimed to measure the association between maternal smoking during pregnancy and offspring's IQ in two birth cohorts from Pelotas, Brazil. Data from the 1982 and 1993 birth cohorts were analyzed. Smoking during pregnancy was ascertained at the perinatal follow-up, and IQ was measured at 30 years (1982) and 18 years (1993). Simple and multiple linear regressions were used for crude and adjusted analysis. Mediation analysis was performed using birth weight and breastfeeding as possible mediators. Data analysis was conducted in 2020. There were 3611 and 4050 participants from the 1982 and 1993 cohorts, respectively. After adjustment for potential confounders, the inverse association between smoking during pregnancy and children's IQ remained significant in both cohorts. Offspring of mothers who smoked during pregnancy had an average of 1.32 less IQ points (95%CI: -2.23, -0.242) in the 1982 cohort, and an average of 1.66 less IQ points (95%CI: -2.42, -0.90) in the 1993 cohort. Neither cohort showed association with paternal smoking (negative controls) after adjustment. Breastfeeding's mediated effects accounted for 26.2% and 23.9% of the association in the 1982 and 1993 cohorts, respectively, while birth weight's accounted for 6.8% and 30.1%, respectively; indirect effects were not significant. The inverse association between maternal smoking and IQ and the lack of association with paternal smoking reinforces our findings of a negative association between exposure and outcome.

Prenatal nicotine alters development of the laterodorsal tegmentum: Possible role for attention-deficit/hyperactivity disorder and drug dependence

As we cycle between the states of wakefulness and sleep, a bilateral cholinergic nucleus in the pontine brain stem, the laterodorsal tegmentum (LDT), plays a critical role in controlling salience processing, attention, behavioral arousal, and electrophysiological signatures of the sub- and microstates of sleep. Disorders involving abnormal alterations in behavioral and motivated states, such as drug dependence, likely involve dysfunctions in LDT signaling. In addition, as the LDT exhibits connectivity with the thalamus and mesocortical circuits, as well as receives direct, excitatory input from the prefrontal cortex, a role for the LDT in cognitive symptoms characterizing attention-deficit/hyperactivity disorder (ADHD) including impulsivity, inflexibility, and dysfunctions of attention is suggested. Prenatal nicotine exposure (PNE) is associated with a higher risk for later life development of drug dependence and ADHD, suggesting alteration in development of brain regions involved in these behaviors. PNE has been shown to alter glutamate and cholinergic signaling within the LDT. As glutamate and acetylcholine are major excitatory mediators, these alterations would likely alter excitatory output to target regions in limbic motivational circuits and to thalamic and cortical networks mediating executive control. Further, PNE alters neuronal development and transmission within prefrontal cortex and limbic areas that send input to the LDT, which would compound effects of differential processing within the PNE LDT. When taken together, alterations in signaling in the LDT are likely to play a role in negative behavioral outcomes seen in PNE individuals, including a heightened risk of drug dependence and ADHD behaviors.

Developmental multi-trajectory of irritability, anxiety, and hyperactivity as psychological markers of heterogeneity in childhood aggression

BACKGROUND

A growing body of evidence suggests that child aggression is likely to be driven by multiple developmental pathways. However, little is known about the complex interactions between developmental trajectories of child psychological factors (such as anxiety, irritability, and hyperactivity/impulsivity dimensions) and their associations with aggression from childhood to adolescence. Therefore, the current study aimed to identify clusters of individuals with different developmental multi-trajectory, investigate their early risk factors, and describe their longitudinal associations with physical aggression.

METHOD

The sample comprised 4898 children derived from the Fragile Families and Child Wellbeing Study. A parallel process growth mixture model was used to identify developmental multi-trajectory groups at 5, 9 and 15 years old. Associations between multi-trajectory group membership and physical aggression were examined with Generalized Estimating Equations models. Finally, multinomial logistic regression was performed to assess perinatal and early risk factors for multi-trajectory groups.

RESULTS

Multi-trajectory groups differed in the magnitude of risk for exhibiting physical aggression, compared to typically developing children. The risk for physical aggression was the most prominent in children who were hyperactive/impulsive and irritable [odds ratio (OR) 6.47; 95% confidence interval (CI) 5.44-7.70] and hyperactive/impulsive, irritable, and anxious (OR 7.68; CI 6.62-8.91). Furthermore, maternal cigarette and alcohol use during pregnancy and maternal depression consistently predicted multi-trajectory groups characterized by problematic levels of at least two co-occurrent psychological symptoms.

CONCLUSIONS

Identified combinations of developmental trajectories of psychological characteristics were associated with different magnitude in risk for exhibiting physical aggression. These results may highlight the heterogeneity of developmental trajectories associated with childhood aggression.

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.

Maternal and child genetic liability for smoking and caffeine consumption and child mental health: an intergenerational genetic risk score analysis in the ALSPAC cohort

BACKGROUND AND AIMS

Previous studies suggest an association between maternal tobacco and caffeine consumption during and outside of pregnancy and offspring mental health. We aimed to separate effects of the maternal environment (intrauterine or postnatal) from pleiotropic genetic effects.

DESIGN

Secondary analysis of a longitudinal study. We (i) validated smoking and caffeine genetic risk scores (GRS) derived from published genome-wide association study (GWAS) for use during pregnancy, (ii) compared estimated effects of maternal and offspring GRS on childhood mental health outcomes and (iii) tested associations between maternal and offspring GRS on their respective outcomes.

SETTING

We used data from a longitudinal birth cohort study from England, the Avon Longitudinal Study of Parents and Children (ALSPAC).

PARTICIPANTS

Our sample included 7921 mothers and 7964 offspring.

MEASUREMENTS

Mental health and non-mental health phenotypes were derived from questionnaires and clinical assessments: 79 maternal phenotypes assessed during and outside of pregnancy and 71 offspring phenotypes assessed in childhood (<10 years) and adolescence (11-18 years).

FINDINGS

The maternal smoking and caffeine GRS were associated with maternal smoking and caffeine consumption during pregnancy (2nd trimester: Psmoking  = 3.0 × 10-7 , Pcaffeine  = 3.28 × 10-5 ). Both the maternal and offspring smoking GRS showed evidence of association with reduced childhood anxiety symptoms (βmaternal  = -0.033; βoffspring  = -0.031) and increased conduct disorder symptoms (βmaternal  = 0.024; βoffspring  = 0.030), after correcting for multiple testing. Finally, the maternal and offspring smoking GRS were associated with phenotypes related to sensation seeking behaviours in mothers and adolescence (e.g. increased symptoms of externalising disorders, extraversion and monotony avoidance). The caffeine GRS showed weaker evidence for associations with mental health outcomes.

CONCLUSIONS

We did not find strong evidence that maternal smoking and caffeine genetic risk scores have a causal effect on offspring mental health outcomes. Our results confirm that the smoking genetic risk scores also captures liability for sensation seeking personality traits.

Maternal smoking during pregnancy and risks to depression and anxiety in offspring: An observational study and genome-wide gene-environment interaction analysis in UK biobank cohort

BACKGROUND

Maternal smoking during pregnancy (MSDP) has been reported to be associated with increased anxiety and depression behaviors in offspring. However, there is still scant evidence to support the link between MSDP and anxiety/depression.

METHODS

Using the subjects from the UK Biobank cohort (n = 371,903-432,881). Logistic regression analyses were first conducted to test the correlation between MSDP and anxiety/depression in offspring. Second, genome-wide gene-environment interaction study (GWGEIS) analyses were conducted by PLINK, using MSDP as environmental factor. Genetic correlation analysis of anxiety/depression and smoking was conducted by the LDSC software using the published genome-wide association study (GWAS) summary data of four smoking traits (n = 337,334-1,232,091), anxiety (n = 31,880) and depression (n = 490,359). Finally, pathway enrichment analysis was carried out to detect the pathway involved in the development of offspring anxiety caused by the interaction of MSDP × SNPs.

RESULTS

Observational analyses showed that anxiety and depression status in offspring were significantly associated with MSDP (all p < 0.0001). Further GWEGI analyses observed significant MSDP-gene interaction effects at UNC80 gene for anxiety (p = 9.09 × 10^-9). LDSC did not detect significant genetic correlation between anxiety and smoking traits. Pathway analysis identified 19 significant pathways for anxiety, such as MANALO_HYPOXIA_UP (FDR = 5.50 × 10^-4), REACTOME_ADHERENS_JUNCTIONS_INTERACTIONS (FDR = 0.0304) and ONDER_CDH1_TARGETS_2_UP (FDR = 0.0371).

CONCLUSION

Our study results suggested the important impact of MDSP on the risk of anxiety in offspring, partly attributing to environment-gene interactions effects.

Prenatal alcohol and tobacco use and the risk of depression in offspring at age of 17 years: findings from the Raine Study

BACKGROUND

Prenatal alcohol and tobacco exposures have been associated with adverse mental health consequences in offspring. The objective of this study was to test the associations between maternal prenatal alcohol and tobacco exposures and depressive symptoms in the offspring, adjusting for a wide range of potential confounders.

METHODS

We used data from 1168 mother-offspring pairs from the Raine Study based in Perth, Western Australia. Depressive symptoms at age 17 years were measured using the Beck Depression Inventory for Youth (BDI-Y). Associations between prenatal alcohol and tobacco use and the risk of depressive symptoms in offspring were estimated by risk ratios (RR) derived with multivariable log-binomial regression.

RESULTS

Among offspring who were assessed for depressive symptoms, 5% were born to mothers who consumed six or more standard drinks of alcohol per week during pregnancy and 20% were exposed to prenatal tobacco. After adjustment for confounders, depressive symptoms at the age of 17 years remained associated with maternal alcohol use of six or more standard drinks per week [RR 1.59 (95% CI: 1.11-2.26)] and any tobacco use [RR 1.36 (95% CI: 1.05-1.79)] during the first trimester of pregnancy.

CONCLUSION

Offspring exposed to prenatal alcohol and tobacco use had greater risks of depressive symptoms compared with unexposed offspring, suggesting early screening and prevention of these exposures could possibly reduce depressive symptoms in offspring.

Effect of Environmental Tobacco Smoke on Children's Anxiety and Behavior in Dental Clinics, Jeddah, Saudi Arabia: A Cross-Sectional Study

Background: Environmental tobacco smoke (ETS) has been linked to behavioral problems, but no study has assessed its relationship with dental anxiety. Therefore, this study’s goal is to assess the relation between ETS and both behavioral problems and dental anxiety among children. Methods: The study sample was collected from two centres in Jeddah from October 2019 to January 2020. Inclusion criteria included healthy 5–16-year-old children having their first dental visit with no emergency complaint. The questionnaire including general information, ETS exposure, the child’s anxiety using the Abeer Children Dental Anxiety Scale (ACDAS) and dental behavior using the Frankl Behavioral Rating Scale. Results: Of 500 children, 337 (67.4% response rate) responded to the questionnaire, among whom 201 (59.6%) had been exposed to passive smoking compared to 136 (40.4%) who had not. Exposed children had a statistically significantly greater tendency to develop anxiety (p = 0.002) and demonstrate uncooperative behavior (p = 0.006). Generalized linear mode and binary regression analyses suggested that ETS has a statistically significant effect on children’s dental anxiety and behavior (p < 0.05). Conclusions: Children exposed to ETS demonstrated statistically significantly higher anxiety levels and uncooperative behavior in the dental clinic compared to those who were not exposed.

The Effect of Smoking during Pregnancy on Severity and Directionality of Externalizing and Internalizing Symptoms: A Genetically Informed Approach

The objective was to examine the association between maternal smoking during pregnancy (SDP) and (I) severity and (II) directionality of externalizing and internalizing symptoms in a sample of sibling pairs while rigorously controlling for familial confounds. The Missouri Mothers and Their Children Study is a family study (N = 173 families) with sibling pairs (aged 7 to 16 years) who are discordant for exposure to SDP. This sibling comparison study is designed to disentangle the effects of SDP from familial confounds. An SDP severity score was created for each child using a combination of SDP indicators (timing, duration, and amount). Principal component analysis of externalizing and internalizing behavior, assessed with the Child Behavior Checklist and Teacher Report Form, was used to create symptom severity and directionality scores. The variance in severity and directionality scores was primarily a function of differences between siblings (71% and 85%, respectively) rather than differences across families (29% and 15%, respectively). The severity score that combines externalizing and internalizing symptom severity was not associated with SDP. However, a significant within-family effect of SDP on symptom directionality (b = 0.07, p = 0.04) was observed in the sibling comparison model. The positive directionality score indicates that SDP is associated with differentiation of symptoms towards externalizing rather than internalizing symptoms after controlling for familial confounds with a sibling comparison model. This supports a potentially causal relationship between SDP and externalizing behavior.

Maternal hypertensive disorders during pregnancy and the trajectories of offspring emotional and behavioral problems: the ALSPAC birth cohort study

PURPOSE

This study examined the effect of hypertensive disorders during pregnancy on trajectories of emotional and behavioral problems in offspring.

METHODS

We used data from the Avon Longitudinal Study of Parents and Children, a prospective birth cohort study in Avon, United Kingdom. A group-based trajectory modeling was used to identify the distinct trajectories of emotional and behavioral problems in children at four time points: at age 3.5, 6.75, 9, and 11 years. Multinomial logistic regression analyses were used to examine the association between hypertensive disorders during pregnancy and trajectories of emotional and behavioral problems.

RESULTS

We identified four trajectories of offspring emotional and behavioral problems: normal (42.6%), borderline decreasing (40.6%), borderline stable (10.0%), and persistently elevated (6.8%). We found that children exposed to maternal pre-eclampsia were more likely to be in the persistently elevated symptom trajectory (OR = 2.72; 95% CI: 1.10-6.74) than in the normal trajectory group. We found no associations between maternal gestational hypertension and trajectories of offspring emotional and behavioral problems.

CONCLUSIONS

Maternal pre-eclampsia, but not gestational hypertension was associated with persistently elevated trajectory of offspring emotional and behavioral problems. Our findings highlight that the antenatal environment is important for children's behavioral and emotional development.

Prenatal risk factors for internalizing and externalizing problems in childhood

BACKGROUND

A growing body of research has documented the effects of prenatal risk factors on a wide spectrum of adverse offspring health outcomes. Childhood behavior problems, such as externalizing and internalizing problems, are no exception. This comprehensive literature review aims to summarize and synthesize current research about commonly experienced prenatal risk factors associated with internalizing and externalizing problems, with a focus on their impact during childhood and adolescence. Potential mechanisms as well as implications are also outlined.

DATA SOURCES

The EBSCO, Web of Science, PubMed, Google Scholar, and Scopus databases were searched for studies examining the association between prenatal risk factors and offspring internalizing/externalizing problems, using keywords "prenatal" or "perinatal" or "birth complications" in combination with "internalizing" or "externalizing". Relevant articles, including experimental research, systematic reviews, meta-analyses, cross-sectional and longitudinal cohort studies, and theoretical literature, were reviewed and synthesized to form the basis of this integrative review.

RESULTS

Prenatal risk factors that have been widely investigated with regards to offspring internalizing and externalizing problems encompass health-related risk factors, including maternal overweight/obesity, substance use/abuse, environmental toxicant exposure, maternal infection/inflammation, as well as psychosocial risk factors, including intimate partner violence, and anxiety/depression. Collectively, both epidemiological and experimental studies support the adverse associations between these prenatal factors and increased risk of emotional/behavioral problem development during childhood and beyond. Potential mechanisms of action underlying these associations include hormonal and immune system alterations. Implications include prenatal education, screening, and intervention strategies.

CONCLUSIONS

Prenatal risk factors are associated with a constellation of offspring internalizing and externalizing problems. Identifying these risk factors and understanding potential mechanisms will help to develop effective, evidence-based prevention, and intervention strategies.

Neurotoxicity of e-cigarettes

It appears that electronic cigarettes (EC) are a less harmful alternative to conventional cigarette (CC) smoking, as they generate substantially lower levels of harmful carcinogens and other toxic compounds. Thus, switching from CC to EC may be beneficial for smokers. However, recent accounts of EC- or vaping-associated lung injury (EVALI) has raised concerns regarding their adverse health effects. Additionally, the increasing popularity of EC among vulnerable populations, such as adolescents and pregnant women, calls for further EC safety evaluation. In this state-of-the-art review, we provide an update on recent findings regarding the neurological effects induced by EC exposure. Moreover, we discuss possible neurotoxic effects of nicotine and numerous other chemicals which are inherent both to e-liquids and EC aerosols. We conclude that in recognizing pertinent issues associated with EC usage, both government and scientific researchers must address this public health issue with utmost urgency.

Global DNA methylation and cognitive and behavioral outcomes at 4 years of age: A cross-sectional study

BACKGROUND

Accumulating evidence suggests that breastfeeding exclusivity and duration are positively associated with child cognition. This study investigated whether DNA methylation, an epigenetic mechanism modified by nutrient intake, may contribute to the link between breastfeeding and child cognition. The aim was to quantify the relationship between global DNA methylation and cognition and behavior at 4 years of age.

METHODS

Child behavior and cognition were measured at age 4 years using the Wechsler Preschool and Primary Scale of Intelligence, third version (WPPSI-III), and Child Behavior Checklist (CBC). Global DNA methylation (%5-methylcytosines (%5mC)) was measured in buccal cells at age 4 years, using an enzyme-linked immunosorbent assay (ELISA) commercial kit. Linear regression models were used to quantify the statistical relationships.

RESULTS

Data were collected from 73 children recruited from the Women and Their Children's Health (WATCH) study. No statistically significant associations were found between global DNA methylation levels and child cognition or behavior (p > .05), though the estimates of effect were consistently negative. Global DNA methylation levels in males were significantly higher than in females (median %5mC: 1.82 vs. 1.03, males and females, respectively, (p < .05)).

CONCLUSION

No association was found between global DNA methylation and child cognition and behavior; however given the small sample, this study should be pooled with other cohorts in future meta-analyses.

Neurodevelopmental pathways in bipolar disorder

Aberrations in neurodevelopmental trajectories have been implicated in the neurobiology of several mental disorders and evidence indicates a pathophysiological and genetic overlap of schizophrenia and bipolar disorder (BD). In this narrative review, we summarize findings related to developmental and perinatal factors as well as epidemiological, clinical, neuropsychological, brain imaging, postmortem brain and genomic studies that provide evidence for a putative neurodevelopmental pathogenesis and etiology of BD. Overall, aberrations in neurodevelopmental pathways have been more consistently implicated in the pathophysiology of schizophrenia compared to BD. Nevertheless, an accumulating body of evidence indicates that dysfunctional neurodevelopmental pathways may be implicated in the underlying pathophysiology of at least a subset of individuals with BD particularly those with an early age of illness onset and those exhibiting psychotic symptoms. A heuristic neurodevelopmental model for the pathophysiology of BD based on the findings of this review is proposed. Furthermore, we critically discuss clinical and research implications of this model. Finally, further research directions for this emerging field are provided.

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.

Prenatal Nicotine Exposure in Rodents: Why Are There So Many Variations in Behavioral Outcomes?

Introduction

The World Health Organization (WHO) reported that smoking cessation rates among women have stagnated in the past decade and estimates that hundreds of millions of women will be smokers in the next decade. Social, environmental, and biological conditions render women more susceptible to nicotine addiction, imposing additional challenges to quit smoking during gestation, which is likely why more than 8% of pregnancies in Europe are associated with smoking. In epidemiological investigations, individuals born from gestational exposure to smoking exhibit a higher risk of development of attention-deficit/hyperactive disorder (ADHD) and liability to drug dependence. Among other teratogenic compounds present in tobacco smoke, nicotine actions during neuronal development could contribute to the observed outcomes as nicotine misleads signaling among progenitor cells during brain development. Several experimental approaches have been developed to address the consequences of prenatal nicotine exposure (PNE) to the brain and behavior but, after four decades of studies, inconsistent data have been reported and the lack of consensus in the field has compromised the hypothesis that gestational nicotine exposure participates in cognitive and emotional behavioral deficits.

Aims

In this review, we discuss the most commonly used PNE models with focus on their advantages and disadvantages, their relative validity, and how the different technical approaches could play a role in the disparate outcomes.

Results

We propose methodological considerations, which could improve the translational significance of the PNE models.

Conclusions

Such alterations might be helpful in reconciling experimental findings, as well as leading to development of treatment targets for maladaptive behaviors in those prenatally exposed.

Implications

In this article, we have reviewed the advantages and disadvantages of different variables of the commonly used experimental models of PNE. We discuss how variations in the nicotine administration methods, the timing of nicotine exposure, nicotine doses, and species employed could contribute to the disparate findings in outcomes for PNE offspring, both in behavior and neuronal changes. In addition, recent findings suggest consideration of epigenetic effects extending across generations. Finally, we have suggested improvements in the available PNE models that could contribute to the enhancement of their validity, which could assist in the reconciliation of experimental findings.

Maternal fever during pregnancy and offspring attention deficit hyperactivity disorder

Maternal fever during pregnancy is associated with several adverse child outcomes. We investigated associations between maternal fever and ADHD among offspring, as well as the sub-dimensions of ADHD - inattention and hyperactivity/impulsivity. Data came from the Norwegian Mother and Child Cohort Study, including more than 114,000 children. Information about children’s ADHD diagnoses was obtained from the Norwegian Patient Register. Mothers reported on inattention and hyperactivity/impulsivity symptoms in questionnaires at 8 years. Logistic regression analysis showed that children exposed to maternal fever in the first trimester received an ADHD diagnosis more often than unexposed children (Odds Ratio (OR) = 1.31, 95% confidence interval (CI) = 1.06–1.61). For children exposed twice or more in the first trimester, the OR was 2.64 (CI = 1.36–5.14). Linear regression analysis showed elevated inattention symptoms among children exposed to fever in the first (Cohen’s d = 0.09, CI = 0.03–0.15) and second (Cohen’s d = 0.05, CI = 0.01–0.09) trimester. Results were similar whether the mother had taken acetaminophen for their fever or not. Hyperactivity/impulsivity symptoms were not related to maternal fever. The results indicate that maternal fever in early pregnancy may be a risk factor for ADHD, and particularly for inattention problems. This risk is neither mitigated nor inflated by use of acetaminophen.

Preventing bias from selective non-response in population-based survey studies: findings from a Monte Carlo simulation study

Background

Health researchers often use survey studies to examine associations between risk factors at one time point and health outcomes later in life. Previous studies have shown that missing not at random (MNAR) may produce biased estimates in such studies. Medical researchers typically do not employ statistical methods for treating MNAR. Hence, there is a need to increase knowledge about how to prevent occurrence of such bias in the first place.

Methods

Monte Carlo simulations were used to examine the degree to which selective non-response leads to biased estimates of associations between risk factors and health outcomes when persons with the highest levels of health problems are under-represented or totally missing from the sample. This was examined under different response rates and different degrees of dependency between non-response and study variables.

Results

Response rate per se had little effect on bias. When extreme values on the health outcome were completely missing, rather than under-represented, results were heavily biased even at a 70% response rate. In most situations, 50–100% of this bias could be prevented by including some persons with extreme scores on the health outcome in the sample, even when these persons were under-represented. When some extreme scores were present, estimates of associations were unbiased in several situations, only mildly biased in other situations, and became biased only when non-response was related to both risk factor and health outcome to substantial degrees.

Conclusions

The potential for preventing bias by including some extreme scorers in the sample is high (50–100% in many scenarios). Estimates may then be relatively unbiased in many situations, also at low response rates. Hence, researchers should prioritize to spend their resources on recruiting and retaining at least some individuals with extreme levels of health problems, rather than to obtain very high response rates from people who typically respond to survey studies. This may contribute to preventing bias due to selective non-response in longitudinal studies of risk factors and health outcomes.

Examining the Association Between Maternal Smoking During Pregnancy and Child Behavior Problems Using Quality-Adjusted Life Years

Objectives Examining the association between maternal smoking and losses in childhood health-related quality of life due to behavior problems provides parents and policymakers another tool for the valuation of smoking cessation during pregnancy. Methods Using the National Longitudinal Survey of Youth 1979 Child and Young Adult data, this study retrospectively examined a cohort of 4114 women and 8668 children. In addition to questions focusing on maternal smoking and general demographics, each survey included the Behavior Problems Index (BPI), a 28-item questionnaire with six subscales measuring childhood behavior problems (antisocial behavior, anxiousness/depression, headstrongness, hyperactivity, immature dependency, and peer conflict/social withdrawal). Responses to the BPI, completed by mothers with children ages 4-14, were summarized on a QALY scale using published preference weights. Results Children whose mothers smoked during pregnancy experience additional QALY losses of 0.181, on average, per year due to increased behavior problems. Boys suffered larger QALY losses associated with maternal smoking (0.242) compared to girls (0.119; p value = .021), regardless of age. Moreover, heavier smoking during pregnancy (i.e., 1 or more packs/day) was associated with larger QALY losses (0.282; p-value < .001). Conclusions for Practice These findings illustrate the burden of maternal smoking during pregnancy on child health, namely behavioral problems. The losses in QALYs may be incorporated into economic evaluations for smoking cessation interventions during pregnancy. Future research will investigate how maternal smoking following childbirth is associated with child QALYs.

Association between violence during pregnancy and preterm birth and low birth weight in Colombia: Analysis of the demographic and health survey

To explore the association between low birth weight and preterm birth with violence during pregnancy, we conducted a cross-sectional study by using the 2010 Colombian Demographic and Health Survey. We conducted bivariate analyses, binomial logistic regression, and stratified models by age, and 14,520 women were included. There was no association between violence and low birth weight. Nonetheless, an association with preterm birth in women aged over 35 was observed (OR 1.98, 95%CI 1.23, 3.17). Prenatal care appeared to be a protective factor for both outcomes. This research unexpectedly showed that supplementation with folic acid and iron was associated with preterm birth.

Characteristics of patients attending the child and adolescent psychiatric outpatient clinic in Erbil city

Background

The Erbil psychiatric hospital is the major governmental psychiatric facility in the governorate of Erbil, the capital of the Kurdistan region in Iraq, providing services for the diagnosis, treatment and follow-up of patients from the city and its surrounding areas. The child and adolescent outpatient clinic in the hospital is for patients younger than 18 years. The objectives of this study were to explore the sociodemographic, pregnancy and birth characteristics, as well as the clinical profiles, of patients who presented to the child and adolescent psychiatric outpatient clinic to statistically estimate the frequency of various psychiatric disorders among the attendees and to test hypotheses of the association of these psychiatric disorders with sociodemographic and birth and pregnancy characteristics as reported by many previous studies but with inconsistent results.

Methods

A descriptive consecutive cross-sectional study was conducted from October 2017 to February 2018 in the Child and Adolescent Psychiatric Outpatient Clinic in Erbil province of Iraq’s Kurdistan region. The diagnostic criteria of the DSM-5 (Diagnostic and Statistical Manual of Mental Disorders, 5^th edition) were implemented. Chi-square tests were used to test the hypothesized associations.

Results

Of a total of 207 patients, 142 were males and 65 were females, and most lived in low socioeconomic status. Most of the patients’ fathers were school educated, and most mothers were illiterate. Consanguinity was found in 41% of the parents, 26.6% of the patients were born by caesarean section(C/S), 62.8% were nurtured exclusively by breastfeeding in their first six months after birth, 42.5% of them visited faith healers before consulting a psychiatrist, 43% had neurodevelopmental disorders, 26.6% had intellectual disabilities with behavioral and emotional comorbidities and 30.4% had other mental/behavioral disorders.

Conclusion

This study revealed that the child and adolescent psychiatric disorders in Erbil city are versatile and that many factors are significantly associated with them. Cultural concepts are still influential in the region in a way that can interfere with children’s well-being, a situation that calls for more concern and attention.

Hypertensive disorders of pregnancy and the risk of anxiety disorders in adolescence: Findings from the Avon Longitudinal Study of Parents and Children

BACKGROUND

The effect of hypertensive disorders of pregnancy (HDP) on offspring anxiety disorders in adolescence is not yet known. This study aims to examine the association between HDP and offspring anxiety disorders at age 15 years.

METHODS

We used data from 5231 mother-offspring pairs from the United Kingdom based Avon Longitudinal Study of Parents and Children (ALSPAC). Anxiety disorder was diagnosed in the offspring at the age of 15 years using the Development and Well-Being Assessment (DAWBA).

RESULTS

Among those who had anxiety disorders, 16.4% were exposed to HDP. After adjusting for a wide range of known confounders, we found that adolescents of women with HDP had a 2.43 fold (95% CI: 1.41-4.19) increase risk of anxiety disorders compared with adolescents of women without HDP.

CONCLUSIONS

Our study showed that adolescents exposed to HDP had higher risk of anxiety disorders compared with unexposed adolescents and suggests that prevention and treatment of maternal HDP could possibly prevent offspring anxiety in adolescence. Early screening for anxiety disorders in offspring of women with HDP may also be warranted. Further research is needed to explain the pathways by which HDP may increase the risk of offspring psychopathology.

The effect of prenatal smoke exposure on child neuropsychological function: a prospective mother-child cohort study

Objective: To study prospectively the effect of prenatal smoke exposure (PSE) on child neuropsychological function and intelligence quotient (IQ).Background: PSE has been associated with adverse effects on child neurodevelopment. However, some studies reported that these associations disappear after adjustment for potential confounders.Methods: A cohortof 248 mothers-child dyad was followed from the first trimester of pregnancy until children were 7.5 years old. PSE was recorded during pregnancy by questionnaire and plasma cotinine. The Wechsler Intelligence Scale for Children, the Neuropsychological Assessment of Executive Functions for Children (ENFEN) and the School Neuropsychological Maturity Questionnaire were administered at 7.5 years of age. The effect of PSE on child IQ and neuropsychological function was assessed with ANCOVA, adjusting for obstetric, neonatal and sociodemographic factors.Results: Children whose mothers smoked throughout pregnancy scored lower in interference (ENFEN) compared to unexposed children (F = 4.1; p = .008). The results showed no differences in other executive functions, verbal and visual memory and IQ between the PSE groups.Conclusion: PSE had little effect on child neuropsychological outcome and was limited to mental flexibility. Nevertheless, these findings support further efforts aimed at encouraging mothers to quit smoking in pregnancy.

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

BACKGROUND

Maternal smoking during pregnancy and parental offending are both linked to adverse offspring outcomes. Few studies have examined how these exposures together influence diverse offspring outcomes in early childhood.

AIMS

To examine associations between quantity of prenatal maternal smoking and frequency of maternal offending and offspring behavioural and cognitive outcomes at age 5 years.

METHODS

Over 66,000 Australian children (mean age 5.6 years) were drawn from an intergenerational data linkage study. Unadjusted and adjusted logistic regressions were conducted for the two key exposures (maternal prenatal smoking and mother having at least two criminal convictions) and offspring behavioural and cognitive vulnerabilities. Population attributable fractions (PAFs) were also estimated for each outcome for the two exposures.

RESULTS

Prenatal smoking and maternal offending were, separately and together, associated with most of the developmental vulnerabilities examined, even after adjusting for other familial and prenatal risk factors. PAFs for prenatal smoking ranged from 5.3% to 15.8%, and PAFs for maternal offending ranged from 3.4% to 11.8% across the offspring outcomes.

CONCLUSIONS

Maternal smoking during pregnancy and maternal offending were uniquely associated with a range of offspring vulnerabilities, but mothers who smoked during pregnancy tended to experience multiple problems that should also be considered as indicators of child vulnerabilities. While early behavioural difficulties were evident in these children, it was striking that they were also likely to have cognitive vulnerabilities. Early intervention to support cognitive development in these children may minimise their risk of academic underachievement, long-term disadvantage, and even offending.

Maternal smoking and low family income during pregnancy as predictors of the relationship between depression and adiposity in young adults

There is an increasing incidence of overweight/obesity and mental health disorders in young adults and the two conditions often coexist. We aimed to investigate the influence of antenatal and postnatal factors that may underlie this association with a focus on maternal prenatal smoking, socio-economic status and gender. Data from the Western Australian Pregnancy Cohort (Raine) Study (women enrolled 1989-1991) including 1056 offspring aged 20 years (cohort recalled 2010-2012) were analyzed (2015-2016) using multivariable models for associations between offspring depression scores (DASS-21 Depression-scale) and body mass index (BMI), adjusting for pregnancy and early life factors and offspring behaviours. There was a significant positive relationship between offspring depression-score and BMI independent of gender and other psychosocial covariates. There was a significant interaction between maternal prenatal smoking and depression-score (interaction coefficient=0.096; 95% CI: 0.006, 0.19, P=0.037), indicating the relationship between depression-score and BMI differed according to maternal prenatal smoking status. In offspring of maternal prenatal smokers, a positive association between BMI and depression-score (coefficient=0.133; 95% CI: 0.05, 0.21, P=0.001) equated to 1.1 kg/m2 increase in BMI for every 1standard deviation (8 units) increase in depression-score. Substituting low family income during pregnancy for maternal prenatal smoking in the interaction (interaction coefficient=0.091; 95% CI: 0.01, 0.17, P=0.027) showed a positive association between BMI and depression score only among offspring of mothers with a low family income during pregnancy (coefficient=0.118; 95% CI: 0.06, 0.18, P<0.001). There were no significant effects of gender on these associations. Whilst further studies are needed to determine whether these associations are supported in other populations, they suggest potentially important maternal behavioural and socio-economic factors that identify individuals vulnerable to the coexistence of obesity and depression in early adulthood.

Heat or Burn? Impacts of Intrauterine Tobacco Smoke and E-Cigarette Vapor Exposure on the Offspring's Health Outcome

Maternal smoking during pregnancy leads to gestational complications and organ disorders in the offspring. As nicotine replacement therapy is often ineffective for smoking cessation, pregnant women turn to alternatives such as heat-not-burn tobacco and e-cigarettes. Recently, the popularly of e-cigarettes has been increasing especially among the youth and pregnant women, mainly due to the advertisements claiming their safety. This has even led to some clinicians recommending their use during pregnancy. E-cigarettes heat e-liquid to produce an aerosol (e-vapor), delivering flavorings and nicotine to the user. However, e-vapor also contains toxins such as formaldehyde along with heavy metals and carcinogenic nitrosamines. In addition, specific flavoring compounds such as diacetyl can be toxic themselves or decompose into toxic compounds such as benzaldehydes. These compounds can induce toxicity, inflammation and oxidative stress in the mothers and can accumulate in the developing fetus, affecting intrauterine development. Recent animal studies suggest that maternal e-vapor exposure during pregnancy could cause respiratory and neurological disorders in the offspring. This review will examine the available literature to shed light on the current understanding of this problem-to-be from lessons learned in animal models.

Generalized Anxiety Disorder (GAD) and Comorbid Major Depression with GAD Are Characterized by Enhanced Nitro-oxidative Stress, Increased Lipid Peroxidation, and Lowered Lipid-Associated Antioxidant Defenses

Accumulating evidence shows that nitro-oxidative pathways play an important role in the pathophysiology of major depressive disorder (MDD) and bipolar disorder (BD) and maybe anxiety disorders. The current study aims to examine superoxide dismutase (SOD1), catalase, lipid hydroperoxides (LOOH), nitric oxide metabolites (NOx), advanced oxidation protein products (AOPP), malondialdehyde (MDA), glutathione (GSH), paraoxonase 1 (PON1), high-density lipoprotein cholesterol (HDL), and uric acid (UA) in participants with and without generalized anxiety disorder (GAD) co-occurring or not with BD, MDD, or tobacco use disorder. Z unit-weighted composite scores were computed as indices of nitro-oxidative stress driving lipid and protein oxidation. SOD1, LOOH, NOx, and uric acid were significantly higher and HDL and PON1 significantly lower in participants with GAD than in those without GAD. GAD was more adequately predicted by increased SOD + LOOH + NOx and lowered HDL + PON1 composite scores. Composite scores of nitro-oxidative stress coupled with aldehyde and AOPP production were significantly increased in participants with comorbid GAD + MDD as compared with all other study groups, namely MDD, GAD + BD, BD, GAD, and healthy controls. In conclusion, GAD is characterized by increased nitro-oxidative stress and lipid peroxidation and lowered lipid-associated antioxidant defenses, while increased uric acid levels in GAD may protect against aldehyde production and protein oxidation. This study suggests that increased nitro-oxidative stress and especially increased SOD1 activity, NO production, and lipid peroxidation as well as lowered HDL-cholesterol and PON1 activity could be novel drug targets for GAD especially when comorbid with MDD.

Locus-specific DNA methylation in the placenta is associated with levels of pro-inflammatory proteins in cord blood and they are both independently affected by maternal smoking during pregnancy

We investigated the impact of maternal smoking during pregnancy on placental DNA methylation and how this may mediate the association between maternal smoking and pro-inflammatory proteins in cord blood. The study population consisted of 27 individuals exposed to maternal smoking throughout pregnancy, 32 individuals exposed during a proportion of the pregnancy, and 61 unexposed individuals. Methylation of 11 regions within 6 genes in placenta tissue was assessed by pyrosequencing. Levels of 7 pro-inflammatory proteins in cord blood were assessed by electrochemiluminescence. Differential methylation was observed in the CYP1A1 promoter and AHRR gene body regions between women who smoked throughout pregnancy and non-smokers on the fetal-side of the placenta and in the GFI1 promoter between women who quit smoking while pregnant and non-smokers on the maternal-side of the placenta. Maternal smoking resulted in elevated levels of IL-8 protein in cord blood, which was not mediated by DNA methylation of our candidate regions at either the maternal or the fetal side of the placenta. Placental DNA methylation was associated with levels of inflammatory proteins in cord blood. Our observations suggest that maternal smoking during pregnancy affects both placental DNA methylation and the neonate's immune response.

Language difficulties and internalizing problems: Bidirectional associations from 18 months to 8 years among boys and girls

Studies have shown that early language difficulties are associated with later internalizing problems. Less is known about the nature of the association: the bidirectional relationship over time, the role of different types of language difficulties, and gender differences. The present study examined bidirectional longitudinal associations between parent-rated language difficulties and internalizing problems in a four-wave cross-lagged model from 18 months to 8 years. Data from the Norwegian Mother and Child Cohort Study were used (N = 114,000). Gender-specific dichotomized language variables were created, and associations were investigated uniquely for boys and girls. Logistic regression analyses showed that all cross-lagged associations from 18 months to 5 years were significant for girls (odds ratios [ORs] = 1.48-1.94). For boys, only internalizing problems at 3 years predicted change in language difficulties (OR = 2.33). From 5 to 8 years, the cross-lagged associations between semantic language difficulties and internalizing problems were significant and strong for girls (ORs = 1.92-2.97) and nonsignificant for boys. The results suggest that the associations between language difficulties and internalizing problems are bidirectional from an early age, and that girls are especially vulnerable for developing co-occurring language difficulties and internalizing problems during the years of transition to school.

Maternal Smoking in Pregnancy and Offspring Depression: a cross cohort and negative control study

Previous reports suggest that offspring of mothers who smoke during pregnancy have greater risk of developing depression. However, it is unclear whether this is due to intrauterine effects. Using data from the Avon Longitudinal Study of Parents and Children (ALSPAC) from the UK (N = 2,869), the Nord-Trøndelag health study (HUNT) from Norway (N = 15,493), the Pelotas 1982 Birth Cohort Study from Brazil (N = 2,626), and the Swedish Sibling Health Cohort (N = 258 sibling pairs), we compared associations of maternal smoking during pregnancy and mother’s partner’s smoking during pregnancy with offspring depression and performed a discordant sibling analysis. In meta-analysis, maternal smoking during pregnancy was associated with higher odds of offspring depression (OR 1.20, 95% CI:1.08,1.34), but mother’s partner’s smoking during pregnancy was not (OR 1.05, 95% CI:0.94,1.17). However, there was only weak statistical evidence that the odds ratios for maternal and mother’s partner’s smoking differed from each other (p = 0.08). There was no clear evidence for an association between maternal smoking during pregnancy and offspring depression in the sibling analysis. Findings do not provide strong support for a causal role of maternal smoking during pregnancy in offspring depression, rather observed associations may reflect residual confounding relating to characteristics of parents who smoke.

Maternal Cigarette Smoke Exposure Worsens Neurological Outcomes in Adolescent Offspring with Hypoxic-Ischemic Injury

Hypoxic-ischemic (HI) encephalopathy occurs in approximately 6 per 1000 term newborns leading to devastating neurological consequences, such as cerebral palsy and seizures. Maternal smoking is one of the prominent risk factors contributing to HI injury. Mitochondrial integrity plays a critical role in neural injury and repair during HI. We previously showed that maternal cigarette smoke exposure (SE) can reduce brain mitochondrial fission and autophagosome markers in male offspring. This was accompanied by increased brain cell apoptosis (active caspase-3) and DNA fragmentation (TUNEL staining). Here, we aimed to investigate whether maternal SE leads to more severe neurological damage after HI brain injury in male offspring. Female BALB/c mice (8 weeks) were exposed to cigarette smoke prior to mating, during gestation, and lactation. At postnatal day 10, half of the pups from each litter underwent left carotid artery occlusion, followed by exposure to 8% oxygen (92% nitrogen). At postnatal day 40-44, maternal SE reduced grip strength in grip traction and foot fault tests, which were also reduced by HI injury to similar levels regardless of the maternal group. Limb coordination was impaired by maternal SE which was not worsened by HI injury. Maternal SE increased anxiety level in the offspring, which was normalized by HI injury. Apoptosis markers were increased in different brain regions by maternal SE, with the cortex having further increased TUNEL by HI injury, along with increased markers of inflammation and mitophagy. We conclude that maternal SE can worsen HI-induced cellular damage in male offspring well into adolescence.

Maternal cigarette smoking during pregnancy and the trajectory of externalizing and internalizing symptoms across childhood: Similarities and differences across parent, teacher, and self reports

Maternal smoking during pregnancy (MSDP) has been associated with symptoms of externalizing (e.g., hyperactivity) and internalizing (e.g., emotional) disorders in childhood. The present research addresses two new questions about the nature of this relation: (1) Do the associations between MSDP and externalizing and internalizing symptoms vary by who reports the symptoms? and (2) Is MSDP associated with changes in symptomatology across childhood? We address these questions with two cohorts from the Longitudinal Study of Australian Children (LSAC). Parents and teachers completed the Strengths and Difficulties Questionnaire up to six times every two years between child ages 4 and 14 in the older cohort (N = 3841) and up to four times between child ages 4 and 10 in the younger cohort (N = 3714); the study children also completed the same questionnaire up to three times starting at age 10. Across the two cohorts, MSDP was associated with more externalizing symptoms as reported by parents, teachers, and self. MSDP was also associated with increases in externalizing symptoms across childhood when teachers assessed the symptoms but not when parents assessed them. Finally, MSDP was not consistently associated with the average level of internalizing symptoms, but it was associated with increases in these symptoms across childhood. The present research indicates a robust association between MSDP and the average level of externalizing symptoms in childhood regardless of who reports the symptoms. It also indicates that whether MSDP is associated with the trajectory of externalizing symptomatology depends on who reports on the symptoms.

Prenatal tobacco exposure, birthweight, and offspring psychopathology

Although prenatal tobacco exposure (PTE) is associated with several adverse offspring mental health outcomes, mechanisms remain unclear. We test whether associations between PTE and offspring psychopathology are explained by birthweight, one of the earliest-occurring outcomes of PTE. The analysis focuses on 238 offspring from a family study of depression with (1) collected prenatal histories and (2) at least one clinical interview in adulthood to assess psychiatric problems. Exposure was categorized by maternal smoking of ≥10 cigarettes daily/nearly daily; diagnostic outcomes were confirmed by clinicians using the best-estimate procedure, blind to exposure. After adjusting for potential confounders, PTE was associated with 0.7lb(9%) lower birthweight (p=0.0002), increased rates of disruptive behavior disorders [males: OR=2.66(1.15,6.16), and (trend) substance use disorders [females: OR=2.23(0.98,5.09)], and decreased rates of mood disorders (males: OR=0.42(0.17,0.98)]. Birthweight was not independently associated with diagnoses and did not mediate the association between exposure and psychopathology. Maternal smoking has long-term adverse consequences for offspring. Although birthweight cannot be manipulated, smoking is a modifiable risk factor. Thus, cessation efforts focused on pregnant women may not only improve maternal wellbeing, but also mitigate adverse proximal (e.g., birthweight) and long-term (psychopathology) outcomes in offspring.

Familial confounding of the association between maternal smoking during pregnancy and internalizing disorders in offspring

BACKGROUND

Maternal smoking has consistently been associated with multiple adverse childhood outcomes including externalizing disorders. In contrast the association between maternal smoking during pregnancy (MSDP) and internalizing (anxiety and depressive) disorders in offspring has received less investigation.

METHOD

We conducted a nationwide cohort study including 957635 individuals born in Denmark between 1991 and 2007. Data on MSDP and diagnoses of depression or anxiety disorders were derived from national registers and patients were followed up from the age of 5 years to the end of 2012. Hazard rate ratios (HRRs) were estimated using stratified Cox regression models. Sibling data were used to disentangle individual- and familial-level effects of MSDP and to control for unmeasured familial confounding.

RESULTS

At the population level, offspring exposed to MSDP were at increased risk for both severe depression [HRR 1.29, 95% confidence interval (CI) 1.22-1.36] and severe anxiety disorders (HRR 1.26, 95% CI 1.20-1.32) even when controlling for maternal and paternal traits. However, there was no association between MSDP and internalizing disorders when controlling for the mother's propensity for MSDP (depression: HRR 1.11, 95% CI 0.94-1.30; anxiety disorders: HRR 0.94, 95% CI 0.80-1.11) or comparing differentially exposed siblings (depression: HRR 1.18, 95% CI 0.75-1.89; anxiety disorders: HRR 0.87, 95% CI 0.55-1.36).

CONCLUSIONS

The results suggest that familial background factors account for the association between MSDP and severe internalizing disorders not the specific exposure to MSDP.

Serious Psychological Distress and Smoking During Pregnancy in the United States: 2008-2014

INTRODUCTION

The current study examined the relationship between acute (past 30 day) and recent (past year but not past 30 day) serious psychological distress (SPD) and smoking during pregnancy among women in the United States overall, stratified by demographic characteristics, and described the change in the prevalence of prenatal smoking among women with and without SPD, from 2008 to 2014.

METHODS

Data were drawn from the National Survey on Drug Use and Health (NSDUH), an annual cross-sectional study of US persons aged 12 and over. SPD and smoking in the past 30 days among pregnant women, aged 18 and older, were examined using logistic regression models. Heterogeneity in this association by demographic characteristics, trends over time, and level of cigarette consumption was also examined.

RESULTS

Prenatal smoking was common. Almost 40% of pregnant women with acute SPD reported smoking, 23% of pregnant women with recent SPD smoked, and 11.7% of pregnant women without recent SPD smoked. No significant change was found in the prevalence of prenatal smoking from 2008 to 2014 in any of these groups. Robust relationships were found between acute (OR = 5.05 [3.64-6.99]) and recent SPD (OR = 2.37 [1.74-3.24]) and smoking; these findings remained after adjusting for demographics.

CONCLUSIONS

SPD and smoking during pregnancy are strongly associated; this relationship is present across all sociodemographic groups and the prevalence of smoking in pregnancy has remained relatively unchanged over the past decade both in the presence and absence of SPD.

IMPLICATIONS

SPD and smoking in pregnancy are robustly linked; the prevalence of smoking in pregnancy is extremely high in women with SPD. Screening women with mental health problems for prenatal smoking, as well as screening pregnant smokers for mental health problems, seems warranted and may assist more women in seeking and utilizing treatment options. Efforts to reduce the prevalence of smoking during pregnancy might specifically target women with SPD, where the potential for impact is substantial.

Developmental toxicity of nicotine: A transdisciplinary synthesis and implications for emerging tobacco products

While the health risks associated with adult cigarette smoking have been well described, effects of nicotine exposure during periods of developmental vulnerability are often overlooked. Using MEDLINE and PubMed literature searches, books, reports and expert opinion, a transdisciplinary group of scientists reviewed human and animal research on the health effects of exposure to nicotine during pregnancy and adolescence. A synthesis of this research supports that nicotine contributes critically to adverse effects of gestational tobacco exposure, including reduced pulmonary function, auditory processing defects, impaired infant cardiorespiratory function, and may contribute to cognitive and behavioral deficits in later life. Nicotine exposure during adolescence is associated with deficits in working memory, attention, and auditory processing, as well as increased impulsivity and anxiety. Finally, recent animal studies suggest that nicotine has a priming effect that increases addiction liability for other drugs. The evidence that nicotine adversely affects fetal and adolescent development is sufficient to warrant public health measures to protect pregnant women, children, and adolescents from nicotine exposure.

Testing Causal Effects of Maternal Smoking During Pregnancy on Offspring's Externalizing and Internalizing Behavior

Maternal smoking during pregnancy (SDP) is associated with increased risk of externalizing and internalizing behaviors in offspring. Two explanations (not mutually exclusive) for this association are direct causal effects of maternal SDP and the effects of genetic and environmental factors common to parents and offspring which increase smoking as well as problem behaviors. Here, we examined the associations between parental SDP and mother rated offspring externalizing and internalizing behaviors (rated by the Child Behavior Checklist/2-3) at age three in a population-based sample of Dutch twins (N = 15,228 pairs). First, as a greater effect of maternal than of paternal SDP is consistent with a causal effect of maternal SDP, we compared the effects of maternal and paternal SDP. Second, as a beneficial effect of quitting smoking before pregnancy is consistent with the causal effect, we compared the effects of SDP in mothers who quit smoking before pregnancy, and mothers who continued to smoke during pregnancy. All mothers were established smokers before their pregnancy. The results indicated a greater effect of maternal SDP, compared to paternal SDP, for externalizing, aggression, overactive and withdrawn behavior. Quitting smoking was associated with less externalizing, overactive behavior, aggression, and oppositional behavior, but had no effect on internalizing, anxious depression, or withdrawn behavior. We conclude that these results are consistent with a causal, but small, effect of smoking on externalizing problems at age 3. The results do not support a causal effect of maternal SDP on internalizing behaviors.