Early Childhood Neurodevelopment Research Articles

Chlorpyrifos Exposure and Urban Residential Environment Characteristics as Determinants of Early Childhood Neurodevelopment

We evaluated whether neighborhood characteristics correlated with early neurodevelopment and whether these characteristics confounded the previously reported association between exposure to chlorpyrifos (an organophosphate insecticide) and neurodevelopment. We obtained prenatal addresses, chlorpyrifos exposure data, and 36-month Psychomotor Development Index (PDI) and Mental Development Index (MDI) scores for a birth cohort in New York City (born 1998-2002). We used data from the 2000 US Census to estimate measures of physical infrastructure, socioeconomic status, crowding, demographic composition, and linguistic isolation for 1-kilometer network areas around each child's prenatal address. Generalized estimating equations were adjusted for demographics, maternal education and IQ, prenatal exposure to tobacco smoke, caretaking environment quality, and building dilapidation. Of 266 children included as participants, 47% were male, 59% were Dominican, and 41% were African American. For each standard deviation higher in neighborhood percent poverty, the PDI score was 2.6 points lower (95% confidence interval [CI] = -3.7, -1.5), and the MDI score was 1.7 points lower (95% CI = -2.6, -0.8). Neighborhood-level confounding of the chlorpyrifos-neurodevelopment association was not apparent. Neighborhood context and chlorpyrifos exposure were independently associated with neurodevelopment, thus providing distinct opportunities for health promotion.

GSTM1 Modify the Effect of Cord Blood Cotinine on Neurodevelopment at Three Days of Age

ISEE-0741 Background and Objective: Maternal exposure to environmental tobacco smoke (ETS) has been reported to be associated with children’s neurobehavioral development but there have been few studies investigating the genetic susceptibilities to maternal ETS exposure during pregnancy on children’s neurodevelopment. The potential health effects are still unclear. The aim of this study was to explore the modification effect of metabolic gene polymorphisms and cord blood cotinine levels on children’s neurodevelopment at three days of age. Methods: The study population was 117 mother-infant pairs who gave birth in Taiwan between August 2004 and January 2005 from Taiwan Birth Panel Study. We interviewed them using a structured questionnaire before delivery, collected umbilical cord blood at birth, and performed the Neonatal Neurobehavioral Examination–Chinese Version (NNE-C) after birth within three days. The NNE-C scale consisted of three parts: behavioral responses, tone and motor patterns, primitive reflexes, and each part contains nine items to test by trained physical therapists. The higher the score is, the poorer the child’s performance. The cotinine in cord blood was used as an indicator of environmental tobacco smoke and was analyzed by using HPLC-MS/MS. The detection limited of this method was 0.05 ng/mL. CYP1A1 MspI, CYP1A1 Ile462Val, GSTT1 and GSTM1 were identified from infant’s DNA. Multiple linear regression models were used to explore the effect of ETS exposure and gene interaction on early child neurodevelopment. Results: High cord blood cotinine exposure combined with a GSTM1 polymorphism was associated with a negative NNE-C score (b ± SE =−1.14 ± 0.47, P-value = 0.016) and a negative primitive reflexes score (b ± SE = −1.97 ± 0.87, P-value = 0.025). Conclusion: It can be concluded that the GSTM1 metabolic gene can modify the effect of maternal exposure to ETS on early child neurodevelopment.

CYP1A1 Ile462Val and GSTT1 modify the effect of cord blood cotinine on neurodevelopment at 2 years of age

Maternal exposure to environmental tobacco smoke (ETS) has been reported to be associated with children's neurobehavioral development but there was no studies investigating the genetic susceptibilities to maternal ETS exposure on children's neurodevelopment. The aim of the study was to explore the modification effect of metabolic gene polymorphisms to cord blood cotinine on children's neurodevelopment at the 2 years of age. This study is one investigation of the Taiwan Birth Panel Study and a total of 145 pregnant women and their neonates were recruited between April 2004 and January 2005. We interviewed them by a structured questionnaire after delivery and collected umbilical cord blood at birth. Cotinine in umbilical cord blood as an indicator of environmental tobacco smoke was analyzed by using HPLC–MS/MS and the detection limited of this method was 0.05 ng/mL. Four metabolic genes, CYP1A1 MspI, CYP1A1 Ile462Val, GSTT1 and GSTM1 were identified. The Comprehensive Developmental Inventory for Infants and Toddlers (CDIIT) was used for assessing children's neurodevelopment at the 2 years of age accompanying with the measurement of Home Observation for Measurement of the Environment scale. We used multiple linear regression models to estimate the effects of cord blood cotinine and gene modification. Cotinine levels were significantly negatively associated with developmental quotients (DQs) of the whole test, and cognitive, language, fine-motor and social subtests of the CDIIT. Lower cognitive and language DQs were found in exposed group with absent type of GSTT1. In addition, the lowest scores in fine-motor and whole test DQs were detected in exposed group with CYP1A1 Ile462Val variant type and GSTT1 absent type. It can be concluded that CYP1A1 Ile462Val and GSTT1 metabolic genes can modify the effect of cord blood cotinine on early child neurodevelopment especially for language and fine motor development.

Organophosphates and Outdoor Air: Harnly et al. Respond

Organophosphates and Outdoor Air: Harnly et al. Respond

Postoperative lactate concentrations predict the outcome of infants aged 6 weeks or less after intracardiac surgery: A cohort follow-up to 18 months

An observational cohort study was conducted in infants less than 6 weeks of age undergoing intracardiac surgery to examine the predictive value of serial postoperative lactate determination on survival and early childhood neurodevelopment. A total of 85 infants with congenital heart disease underwent intracardiac surgery between 1996 and 1999. Differences in serial lactate concentrations after surgery among 3 outcome groups were compared. The predictive value of plasma lactate concentration on outcome (1) at discharge from initial hospitalization and (2) 18 to 24 months postnatal age was examined. Compared with survivors, the nonsurvivors had higher lactate concentrations on admission to the pediatric intensive care unit at day 1 peak and area under the curve of the lactate profile than those of adverse and intact survivors (all P < .001, analysis of variance). Significant differences in the time for lactate concentrations to return to 2 mmol/L or less during the first postoperative day were observed among the groups: nonsurvivors > adverse survivors > intact survivors. Lactate concentrations of less than 7 mmol/L on admission or less than 8 mmol/L at day 1 peak predicted survival with 82% sensitivity and 83% specificity, and positive and negative predictive values of 97% and 43%, respectively (P < .001, chi2). Plasma lactate concentrations were associated with adverse outcome but had lower predictive values compared with that for nonsurvival. Serial lactate determination accurately predicts survival and may help differentiate survivors with adverse outcome from those with intact neurodevelopment in early childhood.

Developmental effects of exposure to environmental tobacco smoke and material hardship among inner-city children

Because of the growing concern that exposures to airborne pollutants have adverse effects on fetal growth and early childhood neurodevelopment, and the knowledge that such exposures are more prevalent in disadvantaged populations, we assessed the joint impact of prenatal exposure to environmental tobacco smoke (ETS) and material hardship on the 2-year cognitive development of inner-city children, adjusted for other sociodemographic risks and chemical exposures. The purpose was to evaluate the neurotoxicant effects of ETS among children experiencing different degrees of socioeconomic disadvantage, within a minority population. The sample did not include children exposed to active maternal smoking in the prenatal period. Results showed significant adverse effects of prenatal residential ETS exposure and the level of material hardship on 2-year cognitive development, as well as a significant interaction between material hardship and ETS, such that children with both ETS exposure and material hardship exhibited the greatest cognitive deficit. In addition, children with prenatal ETS exposure were twice as likely to be classified as significantly delayed, as compared with nonexposed children. Postnatal ETS exposure in the first 2 years of life did not contribute independently to the risk of developmental delay, over and above the risk posed by prenatal ETS exposure. The study concluded that prenatal exposure to ETS in the home has a negative impact on 2-year cognitive development, and this effect is exacerbated under conditions of material hardship in this urban minority sample.

Effects of diet on the neurologic development of children at 5 years of age: The STRIP project

Objectives: To evaluate the effects of diet, serum cholesterol concentrations, and apolipoprotein E phenotype on neurodevelopment of 5-year-old children. Study design: Prospective, 4.4-year cohort study in 496 children. Fat-modified diet was introduced to intervention families of 7-month-old infants. Control children consumed an unrestricted diet. Nutrient intakes, serum cholesterol, and neurodevelopment were studied. The groups were combined in univariate and stepwise multivariate logistic regression analyses. Results: In 13-month-old boys (girls), energy intake was 996 (938) kcal, fat intake 26.6 (26.4) percent of energy (E%), and protein intake 17.2 (17.4) E%. In 5-year-old boys (girls), the intakes were 1484 (1364) kcal, 32.1 (31.9) E%, and 15.5 (15.9) E%, respectively. The intakes of total fat and saturated fat and serum cholesterol were not associated with neurodevelopment. In boys, high intake of protein at 5 years, high intakes of protein at 4 years and cholesterol at 2 years, and high intake of polyunsaturated fatty acids at 3 years predicted favorable outcomes in the tests of speech and language skills, gross motor function and perception, and visual motor skills, respectively. Apolipoprotein E phenotype did not influence the test performance. Conclusions: Moderate restriction of dietary fat has no unfavorable effects on neurodevelopment in early childhood. However, the quality of fat and the relative intake of protein may influence neurodevelopment of the boys. (J Pediatr 2002;140:328-33)

Early childhood neurodevelopment in very low birth weight infants with predischarge apnea

Apnea commonly occurs in preterm infants and may persist beyond term. We prospectively investigated the relationship between apnea that persisted beyond 35 weeks postconceptional age and subsequent neurodevelopment in early childhood. Between January, 1990–November, 1993, we performed predischarge respiratory recordings, using 24-hr, 4-channel pneumography, at 35 weeks or more of postconceptional age in 164 infants (birth weight, <1,250 g; gestational age, ⩽32 weeks), who subsequently underwent multidisciplinary neurodevelopmental assessment at 15–64 (median 24) months of adjusted age. The duration of initial artificial ventilation for respiratory distress syndrome and the grade of intraventricular hemorrhage were independent predictors of neurodevelopmental outcome. Mean oximetry desaturation and frequency of predischarge apnea correlated with mental and motor developmental scores. Mean oximetry desaturation during apnea was an independent predictor for motor score in the total population, and for both mental and motor scores in 50 infants with grade 3 or 4 intraventricular hemorrhage, but not in 114 infants without grade 3 or 4 intraventricular hemorrhage. Despite its limited predictability for early childhood neurodevelopment, predischarge respiratory recordings may be useful in predicting subsequent neurodevelopment of high-risk preterm infants, especially those with severe intraventricular hemorrhage. Pediatr Pulmonol. 1999; 27:14–20. © 1999 Wiley-Liss, Inc.

The outcome of very low birth weight neonates (≤1500 g) rescued by inhaled nitric oxide: Neurodevelopment in early childhood

Although inhaled nitric oxide (INO) improves oxygenation in critically ill neonates, the neurodevelopmental outcome of premature neonates with severe hypoxemic respiratory failure treated with INO has not been reported. Mortality and prospective neurodevelopmental assessment in early childhood were studied in a cohort of 24 very low birth weight neonates (≤1500 g) consecutively admitted from 1993 to 1997 and rescued with INO because of severe hypoxemic respiratory failure (oxygenation index 28 to 52) unresponsive to aggressive conventional treatment. Significant improvements in arterial oxygen tension and oxygenation index with lower inspired oxygen concentration and less ventilator support after initiating INO were observed ( P < .05, analysis of variance). Despite the dramatic improvement in systemic oxygenation, the mortality rate was high (14 of 24, 58%). Only 6 of 23 had normal cranial ultrasonographies. At 13 to 40 (22 ± 10) months of adjusted age, 10 survivors had Bayley Scales mental and psychomotor developmental indexes of 81 ± 21 and 64 ± 22, respectively. Of the 10 children, 5 (50%) were disabled, 2 (20%) were developmentally delayed, and 3 (30%) had normal development. In view of the poor outcome in very low-birth-weight neonates rescued by INO, randomized controlled trials are required to examine the role of INO in premature neonates. Before, during, and after INO therapy, cranial ultrasonography is recommended. (J Pediatr 1998;133:735-9)