Direct and indirect effects of maternal intelligence, maternal age, income, and home environment on intelligence of preterm, low-birth-weight children

Utilizing maternal prenatal cognition as a predictor of newborn brain measures of intellectual development

Identifying reliable indicators of cognitive functioning prior to age five has been challenging. Prior studies have shown that maternal cognition, as indexed by intellectual quotient (IQ) and years of education, predict child intelligence at school age. We examined whether maternal full scale IQ, education, and inhibitory control (index of executive function) are associated with newborn brain measures and toddler language outcomes to assess potential indicators of early cognition. We hypothesized that maternal indices of cognition would be associated with brain areas implicated in intelligence in school-age children and adults in the newborn period. Thirty-seven pregnant women and their newborns underwent an MRI scan. T2-weighted images and surface-based morphometric analysis were used to compute local brain volumes in newborn infants. Maternal cognition indices were associated with local brain volumes for infants in the anterior and posterior cingulate, occipital lobe, and pre/postcentral gyrus - regions associated with IQ, executive function, or sensori-motor functions in children and adults. Maternal education and executive function, but not maternal intelligence, were associated with toddler language scores at 12 and 24 months. Newborn brain volumes did not predict language scores. Overall, the pre/postcentral gyrus and occipital lobe may be unique indicators of early intellectual development in the newborn period. Given that maternal executive function as measured by inhibitory control has robust associations with the newborn brain and is objective, brief, and easy to administer, it may be a useful predictor of early developmental and cognitive capacity for young children.

Association of postnatal exposure to mixture of bisphenol A, Di-n-butyl phthalate and Di-(2-ethylhexyl) phthalate with Children's IQ at 5 Years of age: Mothers and Children's environmental health (MOCEH) study

Early childhood is important for neurodevelopment, and exposure to endocrine disruptors such as bisphenol A (BPA) and phthalates in this period may cause neurodevelopmental disorders and delays. The present study examined the association between exposure to mixtures of BPA and three metabolites of phthalates in early childhood and IQ at 5 years of age. The Mother and Children's Environmental Health (MOCEH) study is a prospective birth cohort study conducted in Korea with 1751 pregnant women enrolled from 2006 to 2010. After excluding those without relevant data, 47 children were included in the final analysis. We measured children's urinary concentrations of metabolites of endocrine-disrupting chemicals (Bisphenol A, mono-(2-ethyl-5-oxohexyl) phthalate, mono-(2-ethyl-5-hydroxyhexyl) phthalate and mono-(2-ethyl-5-butyl) phthalate) at ages of 24 and 36 months. We evaluated the children's IQ with the Korean Wechsler Intelligence Test at the age of 5 years. After adjusting for potential confounders, a multiple linear regression was conducted to examine the associations between individual endocrine-disrupting chemicals and the IQ of the children. Weighted Quantile Sum (WQS) regression and quantile-based g-computation were used to assess the association between IQ at age 5 and exposure to mixtures of BPA and phthalates. In the single-chemical analyses, mono-(2-ethyl-5-butyl) phthalate exposure at 36 months was adversely associated with children's IQ (β = -4.93, 95% confidence interval (CI): -9.22, -0.64). In the WQS regression and quantile-based g-computation analyses, exposure to the mixture of BPA and phthalates was associated with lower IQ [β = -9.13 (P-value = 0.05) and β = -9.18 (P-value = 0.05), respectively]. The largest contributor to the overall association was exposure to mono-(2-ethyl-5-butyl) phthalate at 36 months. In the present study, postnatal exposure to mixtures of BPA and three metabolites of phthalates was associated with decreased IQ of children at age 5.

The Right to Sexuality, Reproductive Health, and Found a Family for People with Intellectual Disability: A Systematic Review

Although sexuality, reproductive health, and starting a family are human rights that should be guaranteed for all citizens, they are still taboo issues for people with intellectual disability (ID), and even more so for women with ID. This paper systematically reviews the current qualitative and quantitative evidence on the rights of people with ID in regard to Articles 23 (right to home and family) and 25 (health, specifically sexual and reproductive health) of the Convention on the Rights of Persons with Disabilities (CRPD). A systematic review of the current literature, following PRISMA 2020, was carried out in ERIC, PsychInfo, Scopus, PubMed, ProQuest, and Web of Science. In all, 151 articles were included for review. The studies were categorized into six themes: attitudes, intimate relationships, sexual and reproductive health, sexuality and sex education, pregnancy, and parenthood. There are still many barriers that prevent people with ID from fully exercising their right to sexuality, reproductive health, and parenthood, most notably communicative and attitudinal barriers. These findings underline the need to continue advancing the rights of people with ID, relying on Schalock and Verdurgo's eight-dimensional quality of life model as the ideal conceptual framework for translating such abstract concepts into practice and policy.

The effect of confounding variables in studies of lead exposure and IQ

Methods proposed to address confounding variables frequently do not adequately distinguish confounding from covariation. A confounder is a variable that correlates both with the outcome and the major exposure variable. Accurate treatment of confounding is crucial to low dose extrapolation of the effects of chemical exposures based on epidemiology studies. This study explores the limitations of current regression models in extrapolation to the low dose region of the dose-response curve due to the existence of unrecognized and uncontrolled confounding, using epidemiological data for lead. Based on the reported data in analyses by Lanphear and colleagues and Crump and colleagues, and drawing on other studies, Wilson and Wilson considered maternal IQ, HOME score, SES, parental education, birthweight, smoking, and race as characteristic variables which may have interaction effects. This analysis identifies confounding variables based on the seven longitudinal cohorts in analyses conducted by Lanphear and colleagues and by Crump and colleagues and confirms maternal IQ, HOME score, maternal education and maternal marital status at birth are "Highly Likely" confounders, while race is a "Likely" confounder. The cohort data were reanalyzed using the methods presented by Crump and colleagues while also considering the interaction among the identified confounding variables. This analysis determined that confounders influence IQ estimates in a quantifiable way that may exceed or at least obscure previously-reported effects of blood lead on IQ with blood lead levels below 5 µg/dL; however, limitations in the datasets make predictions of the low dose dose-response analysis questionable.

NICU infant health severity and family outcomes: a systematic review of assessments and findings in psychosocial research

Many infants (7-15%) spend time in the neonatal intensive care unit (NICU) and continue to experience medical issues after discharge. Family psychological responses range widely depending on burden of care, access to resources, and parental characteristics. The current systematic review examined how infant health severity is assessed and related to family psychological (e.g., mental health) and social (e.g., parent-infant attachment) outcomes. Seventy articles were deemed relevant. Infant health was operationalized in several ways including validated assessments, indices of infant health (e.g., diagnosis, length of stay), or novel measures. Parents of infants with increased medical complications reported greater family impact, increased stress, and more intrusive parenting style. A validated assessment of infant health that utilizes parent report is warranted to allow for more accessible and easily disseminated research across medical centers. Understanding NICU infant health severity and family outcomes can be used to identify families at risk for negative psychosocial sequelae.

Maternal intelligence quotient (IQ) predicts IQ and language in very preterm children at age 5 years

BACKGROUND

Sociodemographic factors are linked to cognitive outcomes in children born very preterm (VPT; ≤30 weeks gestation). The influence of maternal intellectual ability, a heritable trait, is unknown. Also undetermined is the extent to which associations between maternal and child intellectual ability vary according to parenting behaviors that target cognitive stimulation in the home.

METHODS

At age 5 years, 84 VPT and 38 demographically matched full-term (FT) children underwent neurodevelopmental assessment. Children's intellectual ability was assessed using The Wechsler Preschool Primary Scale of Intelligence-III, and language was assessed with the Clinical Evaluation of Language Fundamentals Preschool-2. The Wechsler Test of Adult Reading estimated maternal intellectual ability. The StimQ-Preschool questionnaire provided a measure of cognitive stimulation in the home. Linear mixed-effects models examined independent effects and interactions between maternal intellectual ability and cognitive stimulation on children's outcomes.

RESULTS

After covariate adjustment, maternal intellectual ability was associated with child intellectual (p < .001) and language (p = .002) abilities. Stronger associations were observed in FT mother-child dyads (B = .63, p = .04) than VPT dyads (B = .42, p = .01). Mothers of VPT children reported lower levels of Parental Involvement in Developmental Advance (p = .007) and Parental Verbal Responsiveness (p = .04). Group differences in Parental Involvement in Developmental Advance, but not Parental Verbal Responsivity, persisted after adjusting for social background (p = .03). There was no evidence of an interaction between maternal intellectual ability and Parental Involvement in Developmental Advance (p = .34). Instead, maternal intellectual ability (p < .001) and Parental Involvement in Developmental Advance (p = .05) independently predicted VPT children's outcomes.

CONCLUSIONS

Maternal intellectual ability is an important trait linked to VPT and FT children's intellectual and language outcomes. Prematurity increases variation in the heritability of intellectual ability and shifts children from the expected range based on maternal ability. Parental involvement in activities that help children master new skills may promote cognitive development in VPT children born to mothers of lower intellectual ability.

Air Pollution and Cognitive Development at Age 7 in a Prospective Italian Birth Cohort

BACKGROUND

Early life exposure to air pollution has been linked with cognitive impairment in children, but the results have not been conclusive. We analyzed the association between traffic-related air pollution and cognitive function in a prospective birth cohort in Rome.

METHODS

A cohort of 719 newborns was enrolled in 2003-2004 as part of the GASPII project. At age 7 years, 474 children took the Wechsler Intelligence Scale for Children-III to assess their cognitive development in terms of IQ composite scores. Exposure to air pollutants (NO2, PMcoarse, PM2.5, PM2.5 absorbance) at birth was assessed using land use regression models. We also considered variables indicating traffic intensity. The effect of environmental pollution on IQ was evaluated performing a linear regression model for each outcome, adjusting for gender, child age at cognitive test, maternal age at delivery, parental educational level, siblings, socio-economic status, maternal smoking during pregnancy, and tester. To account for selection bias at enrollment and during follow-up, the regression models were weighted for the inverse probabilities of participation and follow-up.

RESULTS

A 10 μg/m³ higher NO2 exposure during pregnancy was associated with 1.4 fewer points (95% confidence interval = -2.6, -0.20) of verbal IQ, and 1.4 fewer points (95% confidence interval = -2.7, -0.20) of verbal comprehension IQ. Similar associations were found for traffic intensity in a 100 m buffer around home. Other pollutants showed negative associations with larger confidence intervals.

CONCLUSIONS

Consistent with previous evidence, this study suggests an association of exposure to NO2 and traffic intensity with the verbal area of cognitive development.See Video Abstract at http://links.lww.com/EDE/B12.

Effects of maternal vitamin B12 supplementation on early infant neurocognitive outcomes: a randomized controlled clinical trial

Maternal nutritional status during pregnancy impacts fetal brain development. Vitamin B12 plays a vital role in neuronal development. However, findings from studies on the association between maternal B12 status and child cognitive functions have been inconsistent. We performed a randomized, placebo-controlled clinical trial of oral B12 supplementation (50 µg) beginning at <14 weeks of gestation through a 6-week post-partum. In the present study, we report the effects of maternal B12 supplementation on cognitive development in infants at 9 months of age on Bayley Scales of Infant Development-III (BSID-III). One hundred eighty-three pregnant women received vitamin B12, and 183 received placebo. Nine-month BSID-III development score was available in 178 infants. There were no significant differences in maternal sociodemographic characteristics and baseline biochemical measures between infants who underwent BSID-III evaluation and infants who were not evaluated. There were no significant differences in any of the subscales of BSID-III between infants born to mothers who received B12 supplementation (n = 78) vs. placebo (n = 100). On multiple regression analysis, elevated maternal total homocysteine (tHcy) levels adjusted for treatment group, birthweight, parity, income and home environment at second trimester of pregnancy were significantly negatively associated with expressive language (β = 3.13 points, P < 0.001), and in third trimester of pregnancy with expressive language (β = -2.29 points, P < 0.001) and fine motor (β = -1.41 points, P = 0.005) domains of BSID-III. While no significant effects of maternal B12 supplementation were seen on cognitive development in infants at 9 months of age, elevated maternal tHcy levels were associated with poorer cognitive performance in some of the subdomains of BSID-III. In pregnant women with elevated tHcy levels and or B12 deficiencies, it may be worthwhile to study the impact of longer term maternal supplementation on infant cognitive outcomes.

Prematurity and parental self-efficacy: the Preterm Parenting & Self-Efficacy Checklist

There is a lack of research investigating parental self-efficacy in parents of infants born preterm as well as a paucity of parental self-efficacy measures that are domain-specific and theoretically grounded. This study aimed to compare parental self-efficacy in parents of infants born term, preterm and very preterm as well as to test whether parental self-efficacy mediates the relationship between psychological symptoms and parental competence. In order to achieve this, a new measure of parental self-efficacy and parental competence relevant for the preterm population and consistent with Bandura's (1977, 1986, 1989) conceptualisation of self-efficacy was developed. Participants included 155 parents, 83 of whom were parents of very preterm (GA<32 weeks), 40 parents of preterm (GA<37 weeks) and 32 parents of term born infants. Parents completed the Preterm Parenting & Self-Efficacy Checklist (the new measure), Family Demographic Questionnaire, Depression Anxiety Stress Scale and Self-Efficacy Questionnaire. This initial study indicates that the Preterm Parenting & Self-Efficacy Checklist has adequate content validity, construct validity, internal consistency and split half reliability. Contrary to expectations, parents of very preterm infants did not report significantly lower overall levels of parental self-efficacy or significantly higher levels of psychological symptoms compared to parents of preterm and term infants. Parental self-efficacy about parenting tasks mediated the relationship between psychological symptoms and self perceived parental competence as predicted. Clinical implications of the results and suggestions for future research are discussed.

Can the home environment promote resilience for children born very preterm in the context of social and medical risk?

Relationships between the home environment and early developmental outcomes were examined in 166 children born very preterm in one tertiary maternity hospital to explore whether a more optimal home environment could promote resilience. In particular, we explored whether this effect was apparent over and above social risk and children's biological risk, as measured by cerebral white matter abnormality (WMA) evaluated using magnetic resonance imaging (MRI) at term-corrected age and length of hospital stay (LOS), and whether the effect of the home environment differed according to WMA. The home environment and social-emotional outcomes were assessed at 2years' corrected age using the Home Screening Questionnaire (HSQ) and the Infant-Toddler Social and Emotional Assessment (ITSEA). Children's cognitive and motor development was assessed using the Bayley Scales of Infant Development II. A more optimal home environment was associated with better cognitive and social-emotional development after adjusting for social risk, WMA, and LOS. Neonatal cerebral WMA moderated the relationship between the home environment and dysregulation problems only, such that the home environment had less effect on dysregulation for children with mild or moderate to severe WMA. The need to support parents to create an optimal home environment is discussed.

Comparative pain and mood effects in patients with comorbid fibromyalgia and major depressive disorder: secondary analyses of four pooled randomized controlled trials of duloxetine

The objective of this paper is to better understand the relationship of pain and mood in patients with fibromyalgia and comorbid major depressive disorder (MDD). Pooled data from 4 double-blind, placebo-controlled, randomized trials of duloxetine hydrochloride 60-120mg/day in patients with fibromyalgia were included (N=1332). Of these, 350 (26% [147 placebo, 203 duloxetine]) had comorbid MDD (per Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition Text Revision criteria) and were included in these analyses. Primary measures included Brief Pain Inventory average pain; Hamilton Depression Rating Scale or Beck Depression Inventory. Logistic regression was used to evaluate the consistency of treatment effect across various subgroups. Path analysis was used to assess the effect of duloxetine on improvement in pain in the presence of improvement in mood and vice versa. Results indicated that 69% of improvement in pain was a direct effect of treatment, with improvement in mood accounting for 31% of pain response. In conclusion, consistent with our hypothesis, duloxetine produced a substantial direct effect on pain improvement and change in mood exerted a modest indirect effect on pain improvements in patients with fibromyalgia and MDD. Hence, both direct and indirect analgesic and antidepressant properties appear to be relevant for the treatment of these comorbid patients with duloxetine.

Neuropsychological Functioning in Preschool-age Children with Sickle Cell Disease: The Role of Illness-related and Psychosocial Factors

Cognitive and academic deficits have been identified in school-aged children with sickle cell disease (SCD). However, there have been very few identified studies that examine neuropsychological functioning in preschool-age children with SCD. It is important to understand effects of SCD from a developmental perspective and to consider the contribution of environmental factors in this at-risk population. Neuropsychological functioning of preschool-age children with SCD and no history of overt stroke (n = 26) was examined across several domains (language, immediate memory/brief attention, visuospatial/visuoconstructional, motor/visuomotor). The mean Full Scale IQ for the sample was 89.0. Performance on the Immediate Memory/ Brief Attention domain was significantly higher than the other domains, although the pattern of performance was relatively consistent, with mean standard scores ranging from 88.0 to 95.0. Disease severity was not significantly related to cognitive functioning in this group of young children with SCD. Socioeconomic status (SES) was significantly correlated with most domain scores and, based on regression analyses, accounted for 18% to 47% of the variance in functioning. Psychosocial factors, such as number of children living in the home and parental stress levels, were negatively associated with Motor/Visuomotor skills, and weekly hours in school/day care was positively associated with language-related skills. Results suggest that, at this young age, psychosocial risk factors appear to be appropriate targets for intervention, with the goal of improving long-term outcome in children with SCD. Further investigations should include comparison to a matched control group.

The relationship between parenting dimensions and adult achievement: evidence from the Whitehall II Study

This article examines the association between three dimensions of perceived parenting--warmth, strictness, and expectation--and adult cognitive and socioeconomic achievement outcomes. Structural equation models (N = 7,035) were used to examine simultaneously the influence of parenting on adult achievement while controlling for the influence of parental socioeconomic circumstances. Very low and very high level of parental warmth was associated with poor adult achievement. Strictness had a negative and parental expectation a positive relationship with adult achievement. These associations were independent of parental socioeconomic circumstances. Own education was found to mediate 27-56% of the relationship between parenting dimensions and adult achievement. Parental expectation was most strongly related to adult achievement. We conclude that parenting plays a significant role in the development of adult achievement: both cognitive ability and socioeconomic achievement. Moderate levels of warmth, low levels of strictness, and high parental expectation are associated with high adult achievement.

Early focused attention predicts outcome for children born prematurely

There is evidence that early focused, but not casual, attention to objects reflects concurrent regulation of attention and active learning. Because attentional abilities are of particular relevance in preterm infants, we evaluated whether early focused attention would be a better predictor of later attention and cognitive function than casual attention in 55 children born at very low birth weight. Participants were tested initially at 7 months and then at 2, 3, and/or 4/5 years of age. Focused attention was defined as the duration of concentrated examination of objects during independent play. Outcome measures were maternal ratings on standard attention-deficit hyperactivity disorder rating scales and standardized cognitive assessments. Results indicate that 7-month focused attention was predictive of reported problems in hyperactivity/impulsivity at age 4/5 years and cognitive abilities at 2, 3, and 4/5 years; casual attention measures were not related to these outcomes. Early focused attention appears continuous with later attentional skills in at-risk infants and is related to cognitive abilities through the preschool years.

The impact of child maltreatment on expressive syntax at 60 months

Although child maltreatment has often been described as leading to language deficits, the few well-controlled investigations of language acquisition in maltreated children have focused on language content rather than form, or have used qualitative rather than quantitative measures. This study examines syntactic complexity in 19 maltreated and 14 nonmaltreated preschool-aged children. Mother-child dyads participated in play sessions that were transcribed and scored for the presence of morphosyntactic forms in child speech and for specific sentence constructions in maternal speech. Findings indicated that child maltreatment was associated with language delay in both vocabulary and production of syntactic structures. There were also qualitative differences in characteristics of maternal utterances between maltreating and comparison groups. Because maltreatment initially occurred before age 2, this study highlights the long-lasting negative influence of maltreatment on language development and also provides the first demonstration of child language delays and differences in maternal speech within a single maltreatment sample.