Paternal and maternal preconception and maternal pregnancy urinary phthalate metabolite and BPA concentrations in relation to child behavior.

BACKGROUND: Epidemiologic studies on health effects of parental preconception exposures are limited despite emerging evidence from toxicological studies suggesting that such exposures, including to environmental chemicals, may affect offspring health. OBJECTIVE: We investigated whether maternal and paternal preconception and maternal pregnancy urinary phthalate metabolite and bisphenol A (BPA) concentrations were associated with child behavior. METHODS: We analyzed data from the Preconception Environmental exposure And Childhood health Effects (PEACE) Study, an ongoing prospective cohort study of children aged 6-11 years whose parent(s) previously enrolled in the prospective preconception Environment and Reproductive Health (EARTH) study. Using linear mixed models, we estimated covariate-adjusted associations of 11 urinary phthalate metabolite and BPA concentrations collected prior to conception and during pregnancy with Behavioral Assessment System for Children-3 (BASC-3) T-scores (higher scores indicate more problem behaviors). RESULTS: This analysis included 134 mothers, 87 fathers and 157 children (24 sets of twins); parents were predominantly non-Hispanic white (mothers and fathers86%). Higher maternal preconception or pregnancy monobenzyl phthalate (MBzP) concentrations were related to higher mean externalizing problems T-scores in their children (ß = 1.3 per 1-loge unit increase; 95 % CI: -0.2, 2.4 and ß = 2.1, 95 % CI: 0.7, 3.6, respectively). Higher maternal preconception monocarboxyoctyl phthalate (MCOP) was suggested to be related to lower mean externalizing problems T-scores (ß = -0.9; 95 % CI: -1.8, 0.0). Higher paternal preconception MCOP was suggestively associated with lower internalizing problems (ß = -0.9; 95 %CI:-1.9, 0.1) and lower Behavioral Symptoms Index (BSI) T-scores (ß = -1.3; 95 % CI: -2.1, -0.4). CONCLUSION: In this cohort, higher maternal preconception and pregnancy MBzP were associated with worse parent-reported child behavior, while higher maternal and paternal preconception MCOP concentrations were related to lower BASC-3 scores.

Paternal and maternal preconception and maternal pregnancy urinary concentrations of parabens in relation to child behavior.

BACKGROUND: Epidemiologic studies of the effects of parental preconception paraben exposures on child behavior are limited despite emerging evidence suggesting that such exposures may affect offspring neurodevelopment. OBJECTIVE: We investigated whether maternal and paternal preconception and maternal pregnancy urinary concentrations of parabens were associated with child behavior. METHODS: We analyzed data from the Preconception Environmental exposure And Childhood health Effects Study, an ongoing prospective cohort of children aged 6-13 years and their parents. We estimated covariate-adjusted associations of loge -transformed urinary methyl, propyl, and butyl paraben concentrations (individually using linear regression models and as a mixture using quantile g-computation) collected prior to conception and during pregnancy with Behavioral Assessment System for Children-3 and Behavior Rating Inventory of Executive Function T-scores (higher scores indicate more problem behaviors). RESULTS: This analysis included 140 mothers, 81 fathers, and 171 children (25 sets of twins); parents were predominantly non-Hispanic white (88% for both mothers and fathers). In single paraben models, higher paternal preconception urinary propyl and methyl paraben concentrations were associated with higher Internalizing Problem T-scores (propyl paraben ß $\beta \;$ = 1.7; 95% confidence interval: 0.6, 2.8, methyl paraben ß $\beta \;$ = 2.2; 95% confidence interval: 0.5, 3.9) and higher Behavioral Symptom Index T-scores (propyl paraben ß $\beta \;$ = 1.4; 95% confidence interval: 0.3, 2.5, methyl paraben ß $\beta \;$ = 1.6; 95% confidence interval: -0.1, 3.3). Each quantile increase in the paternal mixture of three parabens was associated with a 3.4 (95% confidence interval: 0.67, 6.1) and 2.5 (95% confidence interval: 0.01, 5.0) increased internalizing problem and Behavioral Symptom Index T-scores respectively. Higher paternal preconception ( ß $\beta \;$ = 1.0; 95% confidence interval: 0.04, 1.9) and maternal preconception ( ß $\beta \;$ = 1.1 95% confidence interval: -0.1, 2.2) concentrations of propyl paraben were associated with higher Behavior Rating Inventory of Executive Function Metacognition Index T-scores in children, but the paraben mixtures was not. CONCLUSION: In this cohort, paternal preconception urinary concentrations of propyl and methyl paraben were associated with worse parent-reported child behaviors.

Design and Harmonization Approach for the Multi-Institutional Neurocognitive Discovery Study (MINDS) of Adult Congenital Heart Disease (ACHD) Neuroimaging Ancillary Study: A Technical Note.

Dramatic advances in the management of congenital heart disease (CHD) have improved survival to adulthood from less than 10% in the 1960s to over 90% in the current era, such that adult CHD (ACHD) patients now outnumber their pediatric counterparts. ACHD patients demonstrate domain-specific neurocognitive deficits associated with reduced quality of life that include deficits in educational attainment and social interaction. Our hypothesis is that ACHD patients exhibit vascular brain injury and structural/physiological brain alterations that are predictive of specific neurocognitive deficits modified by behavioral and environmental enrichment proxies of cognitive reserve (e.g., level of education and lifestyle/social habits). This technical note describes an ancillary study to the National Heart, Lung, and Blood Institute (NHLBI)-funded Pediatric Heart Network (PHN) "Multi-Institutional Neurocognitive Discovery Study (MINDS) in Adult Congenital Heart Disease (ACHD)". Leveraging clinical, neuropsychological, and biospecimen data from the parent study, our study will provide structural-physiological correlates of neurocognitive outcomes, representing the first multi-center neuroimaging initiative to be performed in ACHD patients. Limitations of the study include recruitment challenges inherent to an ancillary study, implantable cardiac devices, and harmonization of neuroimaging biomarkers. Results from this research will help shape the care of ACHD patients and further our understanding of the interplay between brain injury and cognitive reserve.

Prenatal ambient air pollutant mixture exposure and neurodevelopment in urban children in the Northeastern United States.

BACKGROUND: Studies of prenatal air pollution (AP) exposure on child neurodevelopment have mostly focused on a single pollutant. We leveraged daily exposure data and implemented novel data-driven statistical approaches to assess effects of prenatal exposure to a mixture of seven air pollutants on cognitive functioning in school-age children from an urban pregnancy cohort. METHODS: Analyses included 236 children born at ≥37 weeks gestation. Maternal prenatal daily exposure levels for nitrogen dioxide (NO2), ozone (O3), and constituents of fine particles [elemental carbon (EC), organic carbon (OC), nitrate (NO3-), sulfate (SO42-), ammonium (NH4+)] were estimated based on residential addresses using validated satellite-based hybrid models or global 3-D chemical-transport models. Children completed Wide Range Assessment of Memory and Learning (WRAML-2) and Conners' Continuous Performance Test (CPT-II) at 6.5 ± 0.9 years of age. Time-weighted levels for mixture pollutants were estimated using Bayesian Kernel Machine Regression Distributed Lag Models (BKMR-DLMs), with which we also explored the interactions in the exposure-response functions among pollutants. Resulting time-weighted exposure levels were used in Weighted Quantile Sum (WQS) regressions to examine AP mixture effects on outcomes, adjusted for maternal age, education, child sex, and prenatal temperature. RESULTS: Mothers were primarily ethnic minorities (81% Hispanic and/or black) reporting ≤12 years of education (68%). Prenatal AP mixture (per unit increase in WQS estimated AP index) was associated with decreased WRAML-2 general memory (GM; ß = -0.64, 95%CI = -1.40, 0.00) and memory-related attention/concentration (AC; ß = -1.03, 95%CI = -1.78, -0.27) indices, indicating poorer memory functioning, as well as increased CPT-II omission errors (OE; ß = 1.55, 95%CI = 0.34, 2.77), indicating increased attention problems. When stratified by sex, association with AC index was significant among girls, while association with OE was significant among boys. Traffic-related pollutants (NO2, OC, EC) and SO42- were major contributors to these associations. There was no significant evidence of interactions among mixture components. CONCLUSIONS: Prenatal exposure to an AP mixture was associated with child neurocognitive outcomes in a sex- and domain-specific manner.

Single Ventricle Reconstruction III: Brain Connectome and Neurodevelopmental Outcomes: Design, Recruitment, and Technical Challenges of a Multicenter, Observational Neuroimaging Study.

Patients with hypoplastic left heart syndrome who have been palliated with the Fontan procedure are at risk for adverse neurodevelopmental outcomes, lower quality of life, and reduced employability. We describe the methods (including quality assurance and quality control protocols) and challenges of a multi-center observational ancillary study, SVRIII (Single Ventricle Reconstruction Trial) Brain Connectome. Our original goal was to obtain advanced neuroimaging (Diffusion Tensor Imaging and Resting-BOLD) in 140 SVR III participants and 100 healthy controls for brain connectome analyses. Linear regression and mediation statistical methods will be used to analyze associations of brain connectome measures with neurocognitive measures and clinical risk factors. Initial recruitment challenges occurred that were related to difficulties with: (1) coordinating brain MRI for participants already undergoing extensive testing in the parent study, and (2) recruiting healthy control subjects. The COVID-19 pandemic negatively affected enrollment late in the study. Enrollment challenges were addressed by: (1) adding additional study sites, (2) increasing the frequency of meetings with site coordinators, and (3) developing additional healthy control recruitment strategies, including using research registries and advertising the study to community-based groups. Technical challenges that emerged early in the study were related to the acquisition, harmonization, and transfer of neuroimages. These hurdles were successfully overcome with protocol modifications and frequent site visits that involved human and synthetic phantoms.

Social cognition and behavioral outcomes in congenital heart disease: profiles and neuropsychiatric comorbidities.

Autism spectrum disorders are more prevalent in children with congenital heart disease (CHD) than in the general population. Children with CHD without diagnosed autism are also at increased risk for neurodevelopmental and psychiatric impairments. We characterized social and behavioral outcomes in children with CHD and examined neurodevelopmental and psychiatric comorbidities. Children without diagnosed autism who underwent infant open-heart surgery were eligible. Parent-reports assessed social communication, unusual behaviors, self-regulation, anxiety, and executive function (EF). Neuropsychological tests assessing theory of mind (ToM), working memory, and verbal comprehension were administered. Outcomes were compared to normative data. Linear regressions were estimated with parent-reported scores and ToM abilities as outcomes. Predictors were anxiety symptoms, parent-reported EF, and working memory scores. Covariates were age, parental education, ADHD diagnosis, and verbal comprehension. Clinically relevant comorbidities were identified (N children scoring ≥1SD below the norm). Fifty-six children (10.8 ± 1.8 years) participated virtually. Compared to norms, children with CHD had impaired ToM, more unusual behaviors (p = .002), and less self-regulation (p = .018), but better social communication (p = .014). "Autism-like" traits were positively associated with anxiety symptoms (ß(95% CI) = 0.28(0.08-0.49), p = .008) and worse working memory (ß(95% CI) = -0.36(-0.59-0.13), p = .003). Twenty-one out of 22 children who displayed clinically relevant social and behavioral scores also showed anxiety symptoms (n = 4), impaired EF (n = 7), or both (n = 10). Children with CHD without diagnosed autism have elevated unusual behaviors, lower self-regulation, and impaired ToM. There is a high risk of co-existing anxiety and impaired EF which may increase disease burden. Targeted therapeutic interventions are needed to reduce long-term psychosocial risks in these children.AbbreviationAttention deficit/hyperactivity disorder (ADHD), Autism Spectrum Rating Scale (ASRS), Behavior Rating Inventory of Executive Functions for school-aged children, 2nd Edition (BRIEF-2), cardiopulmonary bypass (CPB), congenital heart disease (CHD), Empathy/Systematizing Quotient Child Version (ESQ-C), Multidimensional Anxiety Scale for Children, 2nd Edition (MASC-2), Social Responsiveness Scale (School-age form), 2nd Edition (SRS-2), theory of mind (ToM), Theory of Mind Task Battery (ToM-TB), Wechsler Intelligence Scale for Children, 5th edition (WISC-V).

Who benefits most from a prenatal HEPA filter air cleaner intervention on childhood cognitive development? The UGAAR randomized controlled trial.

BACKGROUND: Air pollution exposure during pregnancy affects children's brain function. Maternal stress and nutrition, socioeconomic status, and the child's sex may modify this relationship. OBJECTIVE: To identify characteristics of children with the largest increases in full-scale IQ (FSIQ) after their mothers used HEPA filter air cleaners during pregnancy. METHODS: In this randomized controlled trial we randomly assigned women to receive 1-2 air cleaners or no air cleaners during pregnancy. We analyzed maternal hair samples for cortisol and dehydroepiandrosterone (DHEA). When the children were 48 months old, we measured FSIQ with the Wechsler Preschool and Primary Scale of Intelligence. We evaluated ten potential modifiers of the intervention-FSIQ relationship using interaction terms in separate regression models. To account for correlations between modifiers, we also used a single regression model containing main effects and intervention x modifier terms for all potential modifiers. RESULTS: Among 242 mother-child dyads with complete data, the intervention was associated with a 2.3-point increase (95% CI: -1.5, 6.0 points) in mean FSIQ. The intervention improved mean FSIQ among children of mothers in the bottom (5.4 points; 95% CI: -0.8, 11.5) and top (6.1 points; 95% CI: 0.5, 11.8) cortisol tertiles, but not among those whose mothers were in the middle tertile. The largest between-group difference in the intervention's effect was a 7.5-point (95% CI: -0.7, 15.7) larger increase in mean FSIQ among children whose mothers did not take vitamins than among children whose mothers did take vitamins (interaction p-value = 0.07). We also observed larger benefits among children whose mothers did not complete university, and those with lower hair DHEA concentrations, hair cortisol concentrations outside the middle tertile, or more perceived stress. CONCLUSION: The benefits of reducing air pollution during pregnancy on brain development may be greatest for children whose mothers who do not take vitamins, experience more stress, or have less education.

Association of Potentially Damaging De Novo Gene Variants With Neurologic Outcomes in Congenital Heart Disease.

Importance: Neurodevelopmental disabilities are commonly associated with congenital heart disease (CHD), but medical and sociodemographic factors explain only one-third of the variance in outcomes. Objective: To examine whether potentially damaging de novo variants (dDNVs) in genes not previously linked to neurodevelopmental disability are associated with neurologic outcomes in CHD and, post hoc, whether some dDNVs or rare putative loss-of-function variants (pLOFs) in specific gene categories are associated with outcomes. Design, Setting, and Participants: This cross-sectional study was conducted from September 2017 to June 2020 in 8 US centers. Inclusion criteria were CHD, age 8 years or older, and available exome sequencing data. Individuals with pathogenic gene variants in known CHD- or neurodevelopment-related genes were excluded. Cases and controls were frequency-matched for CHD class, age group, and sex. Exposures: Heterozygous for (cases) or lacking (controls) dDNVs in genes not previously associated with neurodevelopmental disability. Participants were separately stratified as heterozygous or not heterozygous for dDNVs and/or pLOFs in 4 gene categories: chromatin modifying, constrained, high level of brain expression, and neurodevelopmental risk. Main Outcomes and Measures: Main outcomes were neurodevelopmental assessments of academic achievement, intelligence, fine motor skills, executive function, attention, memory, social cognition, language, adaptive functioning, and anxiety and depression, as well as 7 structural, diffusion, and functional brain magnetic resonance imaging metrics. Results: The study cohort included 221 participants in the post hoc analysis and 219 in the case-control analysis (109 cases [49.8%] and 110 controls [50.2%]). Of those 219 participants (median age, 15.0 years [IQR, 10.0-21.2 years]), 120 (54.8%) were male. Cases and controls had similar primary outcomes (reading composite, spelling, and math computation on the Wide Range Achievement Test, Fourth Edition) and secondary outcomes. dDNVs and/or pLOFs in chromatin-modifying genes were associated with lower mean (SD) verbal comprehension index scores (91.4 [20.4] vs 103.4 [17.8]; P = .01), Social Responsiveness Scale, Second Edition, scores (57.3 [17.2] vs 49.4 [11.2]; P = .03), and Wechsler Adult Intelligence Scale, Fourth Edition, working memory scores (73.8 [16.4] vs 97.2 [15.7]; P = .03), as well as higher likelihood of autism spectrum disorder (28.6% vs 5.2%; P = .01). dDNVs and/or pLOFs in constrained genes were associated with lower mean (SD) scores on the Wide Range Assessment of Memory and Learning, Second Edition (immediate story memory: 9.7 [3.7] vs 10.7 [3.0]; P = .03; immediate picture memory: 7.8 [3.1] vs 9.0 [2.9]; P = .008). Adults with dDNVs and/or pLOFs in genes with a high level of brain expression had greater Conners adult attention-deficit hyperactivity disorder rating scale scores (mean [SD], 55.5 [15.4] vs 46.6 [12.3]; P = .007). Conclusions and Relevance: The study findings suggest neurodevelopmental outcomes are not associated with dDNVs as a group but may be worse in individuals with dDNVs and/or pLOFs in some gene sets, such as chromatin-modifying genes. Future studies should confirm the importance of specific gene variants to brain function and structure.

Sleep Patterns in Young Children with Congenital Heart Disease.

Sleep patterns of 419 toddlers with congenital heart disease were comparable with the normative population except for increased likelihood across the cohort of sleeping in parents' room and increased disrupted sleep in children aged 18-23 months. Disrupted sleep patterns were associated with lower maternal education and increased medical complexity.

In utero arsenic exposure and early childhood motor development in the New Hampshire Birth Cohort Study.

Introduction: High-level prenatal and childhood arsenic (As) exposure characteristic of several regions in Asia (e.g., Bangladesh), may impact motor function. However, the relationship between lower-level arsenic exposure (characteristic of other regions) and motor development is largely unstudied, despite the potential for deficient motor skills in childhood to have adverse long-term consequences. Thus, we sought to investigate the association between prenatal As exposure and motor function among 395 children in the New Hampshire Birth Cohort Study, a rural cohort from northern New England. Methods: Prenatal exposure was estimated by measuring maternal urine speciated As at 24-28 weeks of gestation using high-performance liquid chromatography (HPLC) inductively coupled plasma mass spectrometry (ICP-MS) and summing inorganic As, monomethylarsonic acid, and dimethylarsinic acid to obtain total urinary As (tAs). Motor function was assessed with the Bruininks-Oseretsky Test of Motor Proficiency, 2nd Edition (BOT-2) at a mean (SD) age of 5.5 (0.4) years. Results: Children who completed this exam were largely reported as white race (97%), born to married mothers (86%) with a college degree or higher (67%). The median (IQR) gestational urine tAs concentration was 4.0 (5.0) µg/L. Mean (SD) BOT-2 scores were 48.6 (8.4) for overall motor proficiency and 48.2 (9.6) for fine manual control [standard score = 50 (10)], and were 16.3 (5.1) for fine motor integration and 12.5 (4.1) for fine motor precision [standard score = 15 (5)]. We found evidence of a non-linear dose response relationship and used a change-point model to assess the association of tAs with overall motor proficiency and indices of fine motor integration, fine motor precision, and their composite, fine manual control, adjusted for age and sex. In models adjusted for potential confounders, each doubling of urine tAs decreased overall motor proficiency by -3.3 points (95% CI: -6.1, -0.4) for tAs concentrations greater than the change point of 9.5 µg/L and decreased fine motor integration by -4.3 points (95% CI: -8.0, -0.6) for tAs concentrations greater than the change point of 17.0 µg/L. Discussion: In summary, we found that levels of prenatal As exposure above an empirically-derived threshold (i.e., the change point) were associated with decrements in childhood motor development in a US population.

Childhood exposures to environmental chemicals and neurodevelopmental outcomes in congenital heart disease.

BACKGROUND: Children with congenital heart defects have an increased risk of neurodevelopmental disability. The impact of environmental chemical exposures during daily life on neurodevelopmental outcomes in toddlers with congenital heart defects is unknown. METHODS: This prospective study investigated the impacts of early childhood exposure to mixtures of environmental chemicals on neurodevelopmental outcomes after cardiac surgery. Outcomes were assessed at 18 months of age using The Bayley Scales of Infant and Toddler Development-III. Urinary concentrations of exposure biomarkers of pesticides, phenols, parabens, and phthalates, and blood levels of lead, mercury, and nicotine were measured at the same time point. Bayesian profile regression and weighted quantile sum regression were utilized to assess associations between mixtures of biomarkers and neurodevelopmental scores. RESULTS: One-hundred and forty infants were enrolled, and 110 (79%) returned at 18 months of age. Six biomarker exposure clusters were identified from the Bayesian profile regression analysis; and the pattern was driven by 15 of the 30 biomarkers, most notably 13 phthalate biomarkers. Children in the highest exposure cluster had significantly lower adjusted language scores by -9.41 points (95%CI: -17.2, -1.7) and adjusted motor scores by -4.9 points (-9.5, -0.4) compared to the lowest exposure. Weighted quantile sum regression modeling for the overall exposure-response relationship showed a significantly lower adjusted motor score (ß = -2.8 points [2.5th and 97.5th percentile: -6.0, -0.6]). The weighted quantile sum regression index weights for several phthalates, one paraben, and one phenol suggest their relevance for poorer neurodevelopmental outcomes. CONCLUSIONS: Like other children, infants with congenital heart defects are exposed to complex mixtures of environmental chemicals in daily life. Higher exposure biomarker concentrations were associated with significantly worse performance for language and motor skills in this population.

A Cross-validated Ensemble Approach to Robust Hypothesis Testing of Continuous Nonlinear Interactions: Application to Nutrition-Environment Studies.

Gene-environment and nutrition-environment studies often involve testing of high-dimensional interactions between two sets of variables, each having potentially complex nonlinear main effects on an outcome. Construction of a valid and powerful hypothesis test for such an interaction is challenging, due to the difficulty in constructing an efficient and unbiased estimator for the complex, nonlinear main effects. In this work we address this problem by proposing a Cross-validated Ensemble of Kernels (CVEK) that learns the space of appropriate functions for the main effects using a cross-validated ensemble approach. With a carefully chosen library of base kernels, CVEK flexibly estimates the form of the main-effect functions from the data, and encourages test power by guarding against over-fitting under the alternative. The method is motivated by a study on the interaction between metal exposures in utero and maternal nutrition on children's neurodevelopment in rural Bangladesh. The proposed tests identified evidence of an interaction between minerals and vitamins intake and arsenic and manganese exposures. Results suggest that the detrimental effects of these metals are most pronounced at low intake levels of the nutrients, suggesting nutritional interventions in pregnant women could mitigate the adverse impacts of in utero metal exposures on children's neurodevelopment.

Exposure to metal mixtures and neuropsychological functioning in middle childhood.

Elevated exposure to multiple trace metals can be neurotoxic even at relatively low levels. These findings are primarily evident from adult occupational studies as well as in children exposed prenatally or in early childhood. Less research has focused on the neurodevelopmental impacts of exposure to metals among school-aged children. We examined associations between exposure to a mixture of four metals (arsenic, cadmium, manganese, lead) measured in hair and markers of cognition, attention, and behavior among 222 6-12 year old children who participated in a 2009-2010 neurodevelopmental follow-up to the C8 Health Project. Using quantile-based g-computation we estimated the adjusted overall metal mixture effect ψ (95 % CI) as the change in outcome per decile increase in all metals in the mixture. Hair metal levels varied by metal, with cadmium being lowest (median 0.007, interquartile range (IQR) 0.013 µg/g) and lead the highest concentration (median 0.152, IQR 0.252 µg/g). Children's cognitive skills and development, attention/impulsivity, and behavior were all close to standardized population means. Each decile increase in all metals was associated with a Full Scale IQ reduction of 1.01 points (95 % confidence interval (CI) -1.88, -0.15) and Verbal IQ reduction of 1.11 points (95 % CI -1.97, -0.25), adjusted for child age, sex, secondhand smoke exposure, HOME score, maternal education, maternal IQ, and examiner. Maternal report of ADHD-like behaviors and executive functioning also showed adverse associations with the metal mixture. Our findings suggest that similar to exposure during prenatal and early childhood periods, recent exposure to metals during middle childhood is associated with adverse neurodevelopmental consequences. Middle childhood may also be a developmental window of susceptibility to the negative consequences of exposure to environmental neurotoxicants.

Portable HEPA filter air cleaner use during pregnancy and children's autistic behaviors at four years of age: The UGAAR randomized controlled trial.

BACKGROUND: Developmental exposure to airborne particulate matter (PM) may increase children's risk of developing autism spectrum disorder. We quantified the impact of reducing PM exposure during pregnancy on the development of autistic traits in children. We also assessed associations between indoor fine PM (PM2.5) concentrations during pregnancy and autistic traits. METHODS: In this parallel-group randomized controlled trial, we randomized 540 non-smoking pregnant women to receive HEPA filter air cleaners or to a control group, which did not receive air cleaners. We administered the Social Responsiveness Scale (SRS-2) to caregivers when children were a median of 48 months (range: 48 to 51 months). Our primary outcome was the SRS-2 total T-score. We imputed missing data using multiple imputation with chained equations and our primary analysis was by intention to treat. In secondary analyses, we estimated associations between full pregnancy and trimester-specific indoor PM2.5 concentrations and T-scores. RESULTS: We enrolled participants at a median of 11 weeks' gestation. Our analysis included 478 children (233 control, 245 intervention). The intervention reduced average indoor PM2.5 concentrations by 29 % (95 % CI: 21, 37 %). The mean SRS-2 total T-score was 0.5 units lower (95 % CI: -2.5, 1.5) among intervention participants, with evidence of larger benefits for children at the high end of the T-score distribution. An interquartile range (9.6 µg/m3) increase in indoor PM2.5 during pregnancy was associated with 1.8-unit (95 % CI: 0.3, 3.2) increase in mean SRS-2 total T-score. Effect estimates for PM2.5 concentrations by trimester were smaller and confidence intervals spanned no effect. CONCLUSION: Reducing indoor PM during pregnancy had little impact on mean autism-related behavior scores in children. However, indoor PM2.5 concentrations during pregnancy were associated with higher scores. Exposure to particulate matter during pregnancy may influence the development of autistic traits in childhood. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01741051.

The association of prenatal manganese exposure with problem-solving skills and its mediation by the building blocks of executive function.

BACKGROUND: Problem-solving skills build upon three core executive functions: inhibition, working memory, and cognitive flexibility. There is evidence of adverse associations of prenatal exposure to manganese (Mn) with core executive functions, but less is known about Mn associations with problem-solving or potential mediators of this association. OBJECTIVES: This study aimed to investigate the association of prenatal Mn exposure with problem-solving and to identify potential neuropsychological mechanisms through which this association may be mediated. METHODS: Study participants were 410 adolescents from the New Bedford Cohort (NBC) who have undergone periodic evaluations since their birth (1993-1998) to mothers residing near a Massachusetts Superfund site. We investigated the association of cord blood Mn with problem-solving measured by the Delis-Kaplan Executive Function System (D-KEFS) Sorting and Tower subtests (scores scaled to a mean ± SD of 10 ± 3) using multivariable linear regression. Inhibition and cognitive flexibility were also measured by the D-KEFS; working memory was measured with the Wide Range Assessment of Memory and Learning, 2nd edition. Regression-based causal mediation analysis was used to assess the proportion of the Mn-problem-solving association mediated by inhibition, working memory, and cognitive flexibility individually and jointly. RESULTS: NBC adolescents (mean age 15.5 years) were socio-demographically diverse with 31 % in a low-income household at birth and had cord blood Mn concentrations similar to other general population samples. Mn was associated with Sorting but not Tower scores. Specifically, a doubling of cord blood Mn concentrations was associated with - 0.59 points lower (95 % CI: -1.16, -0.03) Sort Recognition score. In mediation analyses, there was suggestive evidence that inhibition, working memory, and cognitive flexibility combined mediated 30 % of the total effect of Mn on Sorting. When analyzed individually, working memory mediated a larger proportion (24 %) of the effect than inhibition or cognitive flexibility. DISCUSSION: We observed adverse associations of cord blood Mn with problem-solving among adolescents. There was suggestive evidence that the building blocks of executive function jointly, and working memory individually, were potentially important mediators of this association.

Long-term cognitive and behavioral outcomes following early exposure to general anesthetics.

PURPOSE OF REVIEW: Nearly 100 clinical studies have been published evaluating neurodevelopmental outcomes in children following surgery and anesthesia. These studies have reported mixed results, likely attributable at least in part to significant heterogeneity in their study designs, types and numbers of exposures, patient populations evaluated, and most importantly, the outcomes that were assessed. This review aims to summarize the results from clinical studies evaluating behavioral outcomes in children exposed to surgery and anesthesia. RECENT FINDINGS: Children with early exposure to surgery and anesthesia were found to have limited to no differences in intelligence when compared with unexposed children. However, several studies have reported more behavioral problems in children exposed to general anesthesia. An increased incidence of attention-deficit hyperactivity disorder has also been reported in anesthetic exposed children, particularly after multiple exposures. SUMMARY: Nearly all clinical studies of anesthetic neurotoxicity are observational in nature, so the associations between anesthetic exposure and behavioral deficits cannot yet be directly attributed to the anesthetic medication. However, the finding of deficits in some neurodevelopmental domains and not others will help guide the selection of appropriate outcomes in future studies of anesthetic neurotoxicity that can further evaluate whether anesthetic medications have an impact on neurodevelopment in children.

Portable HEPA Filter Air Cleaner Use during Pregnancy and Children's Cognitive Performance at Four Years of Age: The UGAAR Randomized Controlled Trial.

BACKGROUND: Developmental exposure to air pollution is associated with diminished cognitive abilities in observational studies, but no randomized controlled trial has examined the effect of reducing air pollution on cognition in children. OBJECTIVES: We sought to quantify the impact of reducing exposure to particulate matter (PM) during pregnancy on children's cognitive performance at 4 y of age. METHODS: In this single-blind, parallel-group, randomized controlled trial in Ulaanbaatar, Mongolia, we randomly assigned 540 nonsmoking pregnant women (268 intervention and 272 control) to receive 1-2 portable high-efficiency particulate air (HEPA) filter air cleaners or no air cleaners. The air cleaners were used from a median of 11 wk gestation until the end of pregnancy. The primary outcome was full-scale intelligence quotient (FSIQ) assessed using the Wechsler Preschool and Primary Scale of Intelligence, Fourth Edition (WPPSI-IV) when children were a median of 48 months old. We imputed missing outcome data using multiple imputation with chained equations, and our primary analysis was by intention to treat. RESULTS: After excluding known miscarriages, stillbirths, neonatal deaths, and medical conditions that impeded cognitive testing and imputation, 475 (233 control and 242 intervention) children were included in our analyses. In an unadjusted analysis, the mean FSIQ of children who were randomly assigned to the intervention group was 2.5 points [95% confidence interval (CI): -0.4, 5.4 points] higher than that of children in the control group. After adjustment to account for an imbalance in preterm birth between groups, the effect estimate increased to 2.8 points (95% CI: -0.1, 5.7). CONCLUSIONS: Reducing PM air pollution during pregnancy may improve cognitive performance in childhood. https://doi.org/10.1289/EHP10302.

Machine Learning to Predict Executive Function in Adolescents with Repaired d-Transposition of the Great Arteries, Tetralogy of Fallot, and Fontan Palliation.

OBJECTIVE: To identify predictors of impaired executive function in adolescents after surgical repair of critical congenital heart disease (CHD). STUDY DESIGN: We analyzed patient factors, medical and surgical history, and family social class from 3 single-center studies of adolescents with d-transposition of the great arteries (d-TGA), tetralogy of Fallot (TOF), and Fontan repair. Machine learning models were developed using recursive partitioning to predict an executive function composite score based on five subtests (population mean 10, SD 3) of the Delis-Kaplan Executive Function System. RESULTS: The sample included 386 patients (139 d-TGA, 91 TOF, 156 Fontan) of age 15.1 ± 2.1 (mean ± SD) years and an executive function composite score of 8.6 ± 2.4. Family social class emerged as the most important predictive factor. The lowest (worst) mean executive function score (5.3) occurred in patients with low to medium social class (Hollingshead index <56) with one or more neurologic events and a diagnosis of TOF. The highest (best) mean score (9.7) occurred in subjects with high social class (Hollingshead index ≥56) and shorter duration of deep hypothermic circulatory arrest. Other factors predicting lower executive function scores included low birth weight and a greater number of catheterizations. CONCLUSIONS: In regression tree modeling, family social class was the strongest predictor of executive function in adolescents with critical CHD, even in the presence of medical risk factors. Additional predictors included CHD diagnosis, birth weight, neurologic events, and number of procedures. These data highlight the importance of social class in mitigating risks of executive dysfunction in CHD.

Anesthesia and Developing Brains: Unanswered Questions and Proposed Paths Forward.

Anesthetic agents disrupt neurodevelopment in animal models, but evidence in humans is mixed. The morphologic and behavioral changes observed across many species predicted that deficits should be seen in humans, but identifying a phenotype of injury in children has been challenging. It is increasingly clear that in children, a brief or single early anesthetic exposure is not associated with deficits in a range of neurodevelopmental outcomes including broad measures of intelligence. Deficits in other domains including behavior, however, are more consistently reported in humans and also reflect findings from nonhuman primates. The possibility that behavioral deficits are a phenotype, as well as the entire concept of anesthetic neurotoxicity in children, remains a source of intense debate. The purpose of this report is to describe consensus and disagreement among experts, summarize preclinical and clinical evidence, suggest pathways for future clinical research, and compare studies of anesthetic agents to other suspected neurotoxins.