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Summary: Introduction: Prevalence and risk factors for elevated glycated haemoglobin (HbA1c) and blood pressure (BP) are poorly understood among Pacific children. We examined associations of HbA1c and BP in 6–9 year‐olds with body mass index (BMI) at ages 2, 5, and BMI velocity between 2–9 years in Samoa. Methods: HbA1c (capillary blood) and BP were measured in n = 410 Samoan children who were part of an ongoing cohort study. Multilevel models predicted BMI trajectory characteristics. Generalized linear regressions assessed associations of childhood characteristics and BMI trajectories with HbA1c and BP treated as both continuous and categorical outcomes. Primary caregiver‐reported childhood characteristics were used as covariates. Results: Overall, 12.90% (n = 53) of children had high HbA1c (≥5.7%) and 33.17% (n = 136) had elevated BP. BMI at 5‐years and BMI velocity were positively associated with high HbA1c prevalence in males. A 1 kg/m2 per year higher velocity was associated with a 1.71 (95% CI: 1.07, 2.75) times higher prevalence of high HbA1c. In females, higher BMI at 5‐years and greater BMI velocity were associated with higher BP at 6–9 years (95% CI: 1.12, 1.40, and 1.42, 2.74, respectively). Conclusion: Monitoring childhood BMI trajectories may inform cardiometabolic disease screening and prevention efforts in this at‐risk population. [ABSTRACT FROM AUTHOR]

Thyroid hormones are essential for neurodevelopment. Few studies have considered associations with quantitatively measured autism spectrum disorder (ASD)‐related traits, which may help elucidate associations for a broader population. Participants were drawn from two prospective pregnancy cohorts: the Early Autism Risk Longitudinal Investigation (EARLI), enrolling pregnant women who already had a child with ASD, and the Health Outcomes and Measures of the Environment (HOME) Study, following pregnant women from the greater Cincinnati, OH area. Gestational thyroid‐stimulating hormone (TSH) and free thyroxine (FT4) were measured in mid‐pregnancy 16 (±3) weeks gestation serum samples. ASD‐related traits were measured using the Social Responsiveness Scale (SRS) at ages 3–8 years. The association was examined using quantile regression, adjusting for maternal and sociodemographic factors. 278 participants (132 from EARLI, 146 from HOME) were included. TSH distributions were similar across cohorts, while FT4 levels were higher in EARLI compared to HOME. In pooled analyses, particularly for those in the highest SRS quantile (95th percentile), higher FT4 levels were associated with increasing SRS scores (β = 5.21, 95% CI = 0.93, 9.48), and higher TSH levels were associated with decreasing SRS scores (β = −6.94, 95% CI = −11.04, −2.83). The association between TSH and SRS remained significant in HOME for the 95% percentile of SRS scores (β = −6.48, 95% CI = −12.16, −0.80), but not EARLI. Results for FT4 were attenuated when examined in the individual cohorts. Our results add to evidence that gestational thyroid hormones may be associated with ASD‐related outcomes by suggesting that relationships may differ across the distribution of ASD‐related traits and by familial likelihood of ASD. Lay Summary: The study examined the association between gestational thyroid hormone levels and ASD‐related traits in two pregnancy cohorts. Our results suggested higher levels of gestational free thyroxine levels and lower levels of thyroid‐stimulating hormone were associated with more ASD‐related traits in children, with variations depending on the degree of clinical impairment and the familial likelihood of ASD. [ABSTRACT FROM AUTHOR]

Background: The pan-Canadian Maternal-Infant Research on Environmental Chemicals (MIREC) study was established to determine whether maternal environmental chemical exposures were associated with adverse pregnancy outcomes in 2001 pregnant women. Objectives: The MIREC-Child Development (CD PLUS) study followed this cohort with the goal of assessing the potential effects of prenatal exposures on anthropometry and neurodevelopment in early childhood. Population: MIREC families with children between the ages of 15 months and 5 years who had agreed to be contacted for future research (n = 1459) were invited to participate in MIREC-CD PLUS which combines data collected from an online Maternal Self-Administered Questionnaire with biomonitoring and neurodevelopment data collected from two in-person visits. Preliminary Results: Between April 2013 and March 2015, 803 children participated in the Biomonitoring visit where we collected anthropometric measures, blood, and urine from the children. The Behavioural Assessment System for Children-2, Behaviour Rating Inventory of Executive Function, MacArthur-Bates Communicative Development Inventories and the Communication subscale of the Adaptive Behaviour Scale from the Bayley Scales of Infant and Toddler Development-III are available on close to 900 children. There were 610 singleton children who completed in-person visits for neurodevelopment assessments including the Social Responsiveness Scale, Wechsler Preschool Primary Scale of Intelligence-III and NEuroPSYchological assessments (NEPSY). Currently, we are following the cohort into early adolescence to measure the impact of early life exposures on endocrine and metabolic function (MIREC-ENDO). Conclusions: Data collection for the MIREC-CD PLUS study is complete and analysis of the data continues. We are now extending the follow-up of the cohort into adolescence to measure the impact of early life exposures on endocrine and metabolic function (MIREC-ENDO). MIREC-CD PLUS is limited by loss to follow-up and the fact that mothers are predominately of higher socioeconomic status and 'White' ethnicity, which limits our generalizability. However, the depth of biomonitoring and clinical measures in MIREC provides a platform to examine associations of prenatal, infancy and childhood exposures with child growth and development. [ABSTRACT FROM AUTHOR]

Background: Toxic metals, like lead, are risk factors for preterm birth (PTB), but few studies have examined low levels found in most Canadians. Vitamin D, which may have antioxidant activity, protects against PTB. Objectives: In this study, we investigated the impact of toxic metals (lead, mercury, cadmium and arsenic) on PTB and examined if maternal plasma vitamin D concentrations modify these associations. Methods: We investigated whether concentrations of metals in whole blood measured in early and late pregnancy were associated with PTB (<37 weeks) and spontaneous PTB in 1851 live births from the Maternal–Infant Research on Environmental Chemicals Study using discrete time survival analysis. We also investigated whether the risk of PTB was modified by first‐trimester plasma 25‐hydroxyvitamin D (25OHD) concentrations. Results: Of 1851 live births, 6.1% (n = 113) were PTBs and 4.9% (n = 89) were spontaneous PTB. A 1 μg/dL increase in blood lead concentrations during pregnancy was associated with an increased risk of PTB (relative risk [RR] 1.48, 95% confidence interval [CI] 1.00, 2.20) and spontaneous PTB (RR 1.71, 95% CI 1.13, 2.60). The risk was higher in women with insufficient vitamin D concentrations (25OHD <50 nmol/L) for both PTB (RR 2.42, 95% CI 1.01, 5.79) and spontaneous PTB (RR 3.04, 95% CI 1.15, 8.04). However, an interaction on the additive scale was not present. Arsenic was associated with a higher risk of PTB (RR 1.10, 95% CI 1.02, 1.19) and spontaneous PTB (RR 1.11, 95% CI 1.03, 1.20) per 1 μg/L. Conclusions: Gestational exposure to low levels of lead and arsenic may increase the risk of PTB and spontaneous PTB; individuals with insufficient vitamin D may be more susceptible to the adverse effects of lead. Given our relatively small number of cases, we encourage testing of this hypothesis in other cohorts, especially those with vitamin D‐deficient populations. [ABSTRACT FROM AUTHOR]

Objective: Excessive gestational weight gain (GWG) has been associated with autism spectrum disorder (ASD). This study sought to examine whether familial susceptibility for autism, intensity of ASD‐related behaviors, or prepregnancy BMI influences the association of GWG with ASD‐related behaviors. Methods: Using data from the Early Autism Risk Longitudinal Investigation (EARLI) study (n = 136), a familial enriched cohort of mothers who had a previous child with ASD, and the Health Outcomes and Measures of the Environment (HOME) study (n = 253), a general population cohort, gestational age and prepregnancy BMI category‐specific GWG z scores were calculated. Caregivers completed the Social Responsiveness Scale (SRS) to assess the presence and severity of ASD‐related traits in children aged 3 to 8 years. Using quantile regression, the association between GWG z scores and ASD‐related behaviors in children was estimated. Results: In HOME, among mothers who had overweight or obesity prepregnancy BMI values, GWG z scores and SRS scores were positively associated in children with more ASD‐related traits (higher SRS scores), but not in children with fewer ASD‐related traits. Similar patterns were observed in EARLI among mothers with prepregnancy obesity. Conclusions: GWG may be associated with autism‐related behaviors among children who have a greater predisposition to these behaviors and who have mothers with prepregnancy overweight or obesity. [ABSTRACT FROM AUTHOR]

Summary: Background: Eating behaviours are associated with childhood obesity, but their associations with cardiometabolic risk are less clear. Objectives: We evaluated cross‐sectional associations between eating behaviours and cardiometabolic risk among 185 adolescents (age 12.4 ± 0.7 years; 53% female; body mass index (BMI)‐z 0.72 ± 1.37) from Cincinnati, Ohio (HOME Study; enrolled 2003–2006). Methods: Caregivers assessed adolescents' eating behaviours with the Child Eating Behaviour Questionnaire. We computed adolescents' cardiometabolic risk scores based on HOMA‐IR, triglycerides to high‐density lipoprotein cholesterol ratio, adiponectin to leptin ratio, systolic blood pressure, and cross‐sectional area of fat inside the abdominal cavity. Using multivariable linear regression models, we estimated associations of eating behaviour subscales with cardiometabolic risk scores or individual risk components. Results: Emotional overeating (ß = 1.34, 95% CI: 0.67, 2.01), food responsiveness (ß = 0.99, 95% CI: 0.41, 1.57), and emotional undereating (ß = 0.64, 95% CI: 0.08, 1.21) were associated with higher cardiometabolic risk scores. Satiety responsiveness (ß = −0.79, 95% CI: −1.59, 0.00) was associated with lower cardiometabolic risk scores. Adjusting for adolescent BMI‐z at age 12 attenuated these associations, suggesting that adiposity may mediate these associations. Conclusion: Hedonistic eating behaviours were associated with higher cardiometabolic risk in these adolescents. [ABSTRACT FROM AUTHOR]

Objective: The study aimed to identify periods of heightened susceptibility to the effects of pre- and postnatal secondhand tobacco smoke (SHS) exposure on body composition at age 12 years.Methods: The study used data from 217 children from the Health Outcomes and Measures of the Environment (HOME) Study, a prospective cohort in Cincinnati, Ohio. Using multiple informant models, the study estimated associations of maternal serum cotinine (16 and 26 weeks of pregnancy) and child serum cotinine concentrations (at age 12, 24, 36, and 48 months) with measures of body composition obtained with anthropometry and dual-energy x-ray absorptiometry at 12 years. We examined whether there were differences between these associations for pre- and postnatal exposure periods and potential effect measure modification by sex.Results: Postnatal cotinine concentrations were associated with higher weight, BMI, body fat and lean mass, waist circumference, and visceral, android, and gynoid fat. Each 10-fold increase in postnatal cotinine was associated with 76% increased risk of overweight or obesity (95% CI: 1.13-2.75). Associations between prenatal concentrations and measures of body composition at 12 years were generally null.Conclusions: Postnatal exposure to SHS may increase adolescent adiposity and lean mass. Future studies should determine whether early-life exposures to SHS are associated with other cardiometabolic risk markers. [ABSTRACT FROM AUTHOR]

Children are exposed to many trace elements throughout their development. Given their ubiquity and potential to have effects on children's neurodevelopment, these exposures are a public health concern. This study sought to identify trace element mixture‐associated deficits in learning behavior using operant testing in a prospective cohort. We included 322 participants aged 6–7 years recruited in Mexico City with complete data on prenatal trace elements measurements (third trimester blood lead and manganese levels, and & urine cadmium and arsenic levels), demographic covariates, and the Incremental Repeated Acquisition (IRA), an associative learning task. Weighted quantile sum (WQS) regression models were used to estimate the joint association of the mixture of all four trace elements and IRA performance. Performance was adversely impacted by the mixture, with different elements relating to different aspects of task performance suggesting that prenatal exposure to trace element mixtures yields a broad dysregulation of learning behavior. [ABSTRACT FROM AUTHOR]

Background Objective Methods Results Conclusion 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.We investigated whether maternal and paternal preconception and maternal pregnancy urinary concentrations of parabens were associated with child behavior.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).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 β$\beta \;$= 1.7; 95% confidence interval: 0.6, 2.8, methyl paraben β$\beta \;$= 2.2; 95% confidence interval: 0.5, 3.9) and higher Behavioral Symptom Index T‐scores (propyl paraben β$\beta \;$= 1.4; 95% confidence interval: 0.3, 2.5, methyl paraben β$\beta \;$= 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 (β$\beta \;$= 1.0; 95% confidence interval: 0.04, 1.9) and maternal preconception (β$\beta \;$= 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.In this cohort, paternal preconception urinary concentrations of propyl and methyl paraben were associated with worse parent‐reported child behaviors. [ABSTRACT FROM AUTHOR]