Faculty Bibliography

OBJECTIVE:We examined the longitudinal associations of age at achieving gross motor milestones and children's development in a US cohort of singletons and twins. METHODS:In the Upstate KIDS study, a population-based study of children born between 2008 and 2010, information on age at achievement of motor milestones and developmental skills was available in 599 children (314 singletons, 259 twins, and 26 triplets). Mothers reported their children's major motor milestones at ∼4, 8, 12, 18, and 24 months. At age 4 years, children's development was clinically assessed by using the Battelle Developmental Inventory, Second Edition (BDI-2). Primary analyses by using multivariate linear regressions were conducted in singletons. We also examined the associations in twins. RESULTS:Later achievement of standing with assistance predicted lower BDI-2 scores in singletons in adjusted models (B per SD of age at achievement, -21.9 [95% confidence interval (CI), -41.5 to -2.2]). Post hoc analysis on age of standing with assistance showed that associations were driven by differences in adaptive skills (B = -5.3 [95% CI, -9.0 to -1.6]) and cognitive skills (B = -5.9 [95% CI, -11.5 to -0.4]). Analyses restricted to twins suggested no association between the age at achievement of milestones and total BDI-2 score after adjustment for gestational age and birth weight. CONCLUSIONS:This study provides evidence that the age of achieving motor milestones may be an important basis for various aspects of later child development. In twins, key predictors of later development (eg, perinatal factors) overshadow the predictive role of milestones in infancy.

BACKGROUND: Few studies have used GPS data to analyze the relationship between Walk Score, transportation choice and walking. Additionally, the influence of Walk Score is understudied using trips rather than individuals as statistical units. The purpose of this study is to examine associations at the trip level between Walk Score, transportation mode choice, and walking among Paris adults who were tracked with GPS receivers and accelerometers in the RECORD GPS Study. METHODS: In the RECORD GPS Study, 227 participants were tracked during seven days with GPS receivers and accelerometers. Participants were also surveyed with a GPS-based web mapping application on their activities and transportation modes for all trips (6969 trips). Walk Score, which calculates neighborhood walkability, was assessed for each origin and destination of every trip. Multilevel logistic and linear regression analyses were conducted to estimate associations between Walk Score and walking in the trip or accelerometry-assessed number of steps for each trip, after adjustment for individual/neighborhood characteristics. RESULTS: The mean overall Walk Scores for trip origins were 87.1 (SD = 14.4) and for trip destinations 87.1 (SD = 14.5). In adjusted trip-level associations between Walk Score and walking only in the trip, we found that a walkable neighborhood in the trip origin and trip destination was associated with increased odds of walking in the trip assessed in the survey. The odds of only walking in the trip were 3.48 (95% CI: 2.73 to 4.44) times higher when the Walk Score for the trip origin was "Walker's Paradise" compared to less walkable neighborhoods (Very/Car-Dependent or Somewhat Walkable), with an identical independent effect of trip destination Walk Score on walking. The number of steps per 10 min (as assessed with accelerometry) was cumulatively higher for trips both originating and ending in walkable neighborhoods (i.e., "Very Walkable"). CONCLUSIONS: Walkable neighborhoods were associated with increases in walking among adults in Paris, as documented at the trip level. Creating walkable neighborhoods (through neighborhood design increased commercial activity) may increase walking trips and, therefore, could be a relevant health promotion strategy to increase physical activity.

Perchlorate is an endocrine-disrupting chemical that interferes with the normal functioning of the thyroid gland. Maternal thyroid dysfunction during gestation may alter fetal brain development. Perchlorate contamination is widespread: it is present in the body of all Americans tested and the majority of foods tested. The main sources of food contamination appear to be hypochlorite bleach, a disinfectant and sanitizer, that when poorly managed quickly degrades to perchlorate and perchlorate-laden plastic food packaging for dry food or localized contamination from manufacturing or processing of the chemical. Eliminating perchlorate from food packaging and improving bleach management, such as reducing concentration and storage time and temperature, would result in reduced perchlorate contamination of food and water.

BACKGROUND: Dietary composition has been associated with sleep indexes. However, most of the evidence is based on cross-sectional data, and studies in young children are lacking. OBJECTIVE: The aim of this study was to explore the longitudinal associations of macronutrient composition of the diet with sleep duration and consolidation (number of awakenings) in infancy and early childhood. METHODS: The study was performed in 3465 children from the Generation R Study, a population-based cohort study in the Netherlands. Mothers reported their child's food intake at 13 mo of age by using a validated food-frequency questionnaire and their child's sleep patterns at 2 and 3 y of age. We used nutrient substitution models to assess the associations of relative macronutrient intakes with sleep indexes and adjusted the models for sociodemographic and lifestyle factors. RESULTS: Isocaloric substitution of fat intake by protein or carbohydrate in infancy was associated with longer total sleep duration at 2 but not 3 y of age. For each 5% increase in energy intake of either protein or carbohydrate at the expense of fat, sleep duration at 2 y of age was longer by 6 min (95% CI: 0.4, 12 min) and 4 min (95% CI: 2, 6 min), respectively. Further exploration of macronutrient subtypes indicated no consistent differences between saturated or unsaturated fat and that intake of plant compared with animal protein or Trp did not explain the association of higher total protein intake with longer sleep duration at 2 y of age. Replacing unsaturated with saturated fat was associated with 7 min (95% CI: -13, -1 min) shorter total sleep duration at 3 y of age. Macronutrient intakes were not associated with sleep consolidation. CONCLUSIONS: Our results suggest that the macronutrient composition of the diet is associated with sleep duration in young children. Future research should further study the causality of this association and explore the underlying mechanisms.

omega-3 and omega-6 polyunsaturated fatty acids are important for brain function and development. We examined whether maternal polyunsaturated fatty acid status during pregnancy affects risk of autistic traits in childhood. Within the Generation R cohort, we measured maternal plasma polyunsaturated fatty acid concentrations and the omega-3:omega-6 ratio in midpregnancy (Rotterdam, the Netherlands, 2001-2005). Child autistic traits at 6 years were assessed by using the Social Responsiveness Scale short form in 4,624 children. A lower maternal omega-3:omega-6 ratio during pregnancy was associated with more autistic traits in the offspring (beta = -0.008, 95% confidence interval: -0.016, -0.001). In particular, a higher total omega-6 and linoleic acid status were associated with more autistic traits (all P's < 0.05). Associations were independent of child intelligence, suggesting that the fatty acid distribution specifically affects the development of autistic traits in addition to general neurodevelopment. Maternal plasma omega-3 status was not associated with child autistic traits and, consistently, neither was prenatal dietary fish intake. Our study shows that a lower prenatal omega-3:omega-6 ratio is associated with more child autistic traits, which is largely accounted for by higher omega-6 instead of lower omega-3 status. These results suggest a biological pathway between maternal fatty acid intake during pregnancy and autistic traits in the offspring.

We estimated the economic costs of female reproductive disorders attributable to endocrine disrupting chemical exposures. These may contribute substantially to fibroids and endometriosis, costing nearly euro1.5 billion annually.

BACKGROUND: Exposure to elevated levels of inflammatory markers during pregnancy has been suggested as possible aetiologic factor in the occurrence of autism spectrum disorder (ASD). In this study, we investigated the prospective relation between maternal C-reactive protein (CRP) during early pregnancy and children's autistic traits in the general population. METHODS: In a large population-based cohort in the Netherlands, we measured maternal CRP levels before 18 weeks of gestation (N = 4165). Parents reported on their children's autistic traits at age 6 years using the Social Responsiveness Scale, and the Pervasive Developmental Problem scale. Regression models were used to examine the relation between maternal CRP levels and autistic traits in children. RESULTS: Compared with the reference group (CRP < 2.3 mg/L), elevated levels of CRP (>7.8 mg/L) in pregnant women were associated with higher Social Responsiveness Scale scores in children [beta = 0.055, 95% confidence interval (CI) 0.033, 0.078]; however, the effect was strongly attenuated after adjustment for several socioeconomic factors and in particular by maternal health-related factors including body mass index (fully adjusted model beta = 0.018, 95% CI -0.005, 0.042). We found no relation between maternal CRP levels and pervasive developmental problem. CONCLUSIONS: Our results suggest that the association between elevated levels of maternal CRP in pregnancy and autistic traits in children is confounded by maternal health-related and socioeconomic factors. Further studies are needed to explore whether other maternal inflammatory markers during pregnancy, as a response to maternal inflammation, are associated with the development of autistic traits in the offspring.

IMPORTANCE: An increasing percentage of births are conceived with assisted reproductive technology (ART) and other infertility treatment. Despite findings that such treatments may be associated with diminished gestation and birth size, scarce data exist regarding infertility treatments and children's development in the United States. OBJECTIVE: To assess the use and type of infertility treatment in relation to children's development through age 36 months. DESIGN, SETTING, AND PARTICIPANTS: Prospective cohort study (conducted 2008-2014) that sampled based on infertility treatment and plurality. Included in the study were infants born between 2008 and 2010 in New York state (excluding New York City) whose parents completed developmental screening instruments through 36 months of age. A total of 4824 mothers (97% of 4989) completed 1 or more developmental screening instruments for 5841 children, including 1830 conceived with infertility treatment and 2074 twins. EXPOSURES: Maternal self-report of any infertility treatment was further categorized into ART and ovulation induction/intrauterine insemination. Assisted reproductive technology use was previously validated by linkage with the Society for Assisted Reproductive Technology-Clinical Outcome Reporting System. MAIN OUTCOMES AND MEASURES: Five developmental domains (fine motor, gross motor, communication, personal-social functioning, and problem-solving ability), as measured by the parental completion of the Ages and Stages Questionnaires at 4, 8, 12, 18, 24, 30, and 36 months of age. Generalized linear mixed modeling techniques estimated adjusted odds ratios (aORs) and 95% CIs for use and type of infertility treatment in relation to failing a developmental domain. Data were stratified by plurality and weighted for the sampling scheme. RESULTS: There were 1422 mothers (29.5%; mean [SD], age, 34.1 [5.2] years) who underwent infertility treatment. Infertility treatment was not associated with risk of their children failing any developmental domain (aOR, 1.33; 95% CI, 0.94-1.89). Assisted reproductive technology was associated with increased risk for failing any developmental domain but only when singletons and twins were evaluated together (aOR, 1.81; 95% CI, 1.21-2.72). Adjustment for birth weight further attenuated this estimate (aOR, 1.26; 95% CI, 0.82-1.93). After stratifying by plurality, type of treatment also was not significantly associated with failing any developmental domain for ovulation induction/intrauterine insemination (aOR, 1.00; 95% CI, 0.57-1.77 for singletons and aOR, 1.30; 95% CI, 0.76-2.21 for twins) or ART (aOR, 1.38; 95% CI, 0.78-2.43 for singletons and aOR, 1.58; 95% CI, 0.94-2.65 for twins). CONCLUSIONS AND RELEVANCE: After considering plurality, children's development through age 3 years was similar irrespective of infertility treatment or specific type. To our knowledge, these findings are among the first to focus on non-ART treatments in the United States.

OBJECTIVE: Recent evidence has suggested that polycyclic aromatic hydrocarbons (PAHs) may contribute to cardiometabolic and kidney dysfunction by increasing oxidative stress, but little is known about impacts in childhood. STUDY DESIGN: We performed cross-sectional analyses of 660 adolescents aged 12-19 years in the 2003-2008 National Health and Nutrition Examination Survey (NHANES), using levels of 10 monohydroxylated urinary PAH metabolites as our exposure. Our primary outcomes of interest were biomarkers of oxidative stress and renal function, including estimated glomerular filtration rate (eGFR), urinary albumin to creatinine ratio (ACR), insulin resistance, and serum uric acid, gamma glutamyl transferase (GGT) and C-reactive protein (CRP). RESULTS: We observed statistically significant associations between PAH metabolites and levels of serum GGT, CRP, uric acid and eGFR. Each 100% increase in 2-hydroxyphenanthrene was related to a 3.36% increase in uric acid (95% CI: 0.338-6.372; p=0.032), a 3.86% increase in GGT (95% CI: 1.361-6.362; p=0.005) and a 16.78% increase in CRP (95% CI: 1.848-31.689; p=0.029). Each 100% increase in 4-hydroxyphenanthrene was associated with a 6.18% increase in GGT (95% CI: 4.064-8.301; p<0.001) and a 13.66% increase in CRP (95% CI: 2.764-24.564; p=0.017). Each 100% increase in 9-hydroxyfluorene was associated with a 2.58% increase in GGT (95% CI: 0.389-4776; p=0.024). Each 100% increase in 3-hydroxyphenanthrene was associated with a 2.66% decrease in eGFR (95% CI: -4.979 to -0.331; p=0.028). CONCLUSIONS: Urinary PAH metabolites were associated with serum uric acid, GGT and CRP, suggesting possible impacts on cardiometabolic and kidney function in adolescents. Prospective work is needed to investigate the potential long-term health consequences of these findings.