Increased risk of learning disabilities in low birth weight boys at age 11 years

Machine learning analysis with population data for prepregnancy and perinatal risk factors for the neurodevelopmental delay of offspring

Neurodevelopmental disorders (NDD) in offspring are associated with a complex combination of pre-and postnatal factors. This study uses machine learning and population data to evaluate the association between prepregnancy or perinatal risk factors and the NDD of offspring. Population-based retrospective cohort data were obtained from Korea National Health Insurance Service claims data for 209,424 singleton offspring and their mothers who gave birth for the first time in 2007. The dependent variables were motor development disorder (MDD), cognitive development disorder (CDD) and combined overall neurodevelopmental disorder (NDD) from offspring. Seventeen independent variables from 2002 to 2007 were included. Random forest variable importance and Shapley Additive Explanation (SHAP) values were calculated to analyze the directions of its associations with the predictors. The random forest with oversampling registered much higher areas under the receiver-operating-characteristic curves than the logistic regression of interaction and non-linearity terms, 79% versus 50% (MDD), 82% versus 52% (CDD) and 74% versus 50% (NDD). Based on random forest variable importance, low socioeconomic status and age at birth were highly ranked. In SHAP values, there was a positive association between NDD and pre- or perinatal outcomes, especially, fetal male sex with growth restriction associated the development of NDD in offspring.

Industrial air pollution and low birth weight in New Mexico, USA

In recent decades, the low birth weight (LBW) rate in New Mexico has consistently exceeded the Unites States average. Maternal exposure to air pollution during pregnancy may be a significant contributor to LBW in offspring. This study investigated the links between maternal residential exposure to air pollution from industrial sources and the risk of LBW in offspring. The analysis included 22,375 LBW cases and 233,340 controls. It focused on 14 common chemicals listed in the Toxic Release Inventory (TRI) and monitoring datasets, which have abundant monitoring samples. The Emission Weighted Proximity Model (EWPM) was used to calculate maternal air pollution exposure intensity. Adjusted odds ratios (adjORs) were calculated using binary logistic regressions to examine the association between maternal residential air pollution exposure and LBW, while controlling for potential confounders, such as the maternal age, race/ethnicity, gestational age, prenatal care, education level, consumption of alcohol during pregnancy, public health regions, child's sex, and the year of birth. Multiple comparison correction was applied using the False Discovery Rate approach. The results showed that maternal residential exposure to 1,2,4-trimethylbenzene, benzene, chlorine, ethylbenzene, and styrene had significant positive associations with LBW in offspring, with adjusted odds ratios ranging from 1.10 to 1.13. These five chemicals remained as significant risk factors after dividing the estimated exposure intensities into four categories. In addition, significant linear trends were found between LBW and maternal exposure to each of the five identified chemicals. Furthermore, 1,2,4-trimethylbenzene was identified as a risk factor to LBW for the first time. The findings of this study should be confirmed through additional epidemiological, biological, and toxicological studies.

Sex differences in the effects of prematurity and/or low birthweight on neurodevelopmental outcomes: systematic review and meta-analyses

BACKGROUND

Premature birth and/or low birthweight have long-lasting effects on cognition. The purpose of the present systematic review is to examine whether the effects of prematurity and/or low birth weight on neurodevelopmental outcomes differ between males and females.

METHODS

Web of Science, Scopus, and Ovid MEDLINE were searched for studies of humans born premature and/or of low birthweight, where neurodevelopmental phenotypes were measured at 1 year of age or older. Studies must have reported outcomes in such a way that it was possible to assess whether effects were greater in one sex than the other. Risk of bias was assessed using both the Newcastle-Ottawa scale and the National Institutes of Health Quality assessment tool for observational cohort and cross-sectional studies.

RESULTS

Seventy-five studies were included for descriptive synthesis, although only 24 presented data in a way that could be extracted for meta-analyses. Meta-analyses found that severe and moderate prematurity/low birthweight impaired cognitive function, and severe prematurity/low birthweight also increased internalizing problem scores. Moderate, but not severe, prematurity/low birthweight significantly increased externalizing problem scores. In no case did effects of prematurity/low birthweight differ between males and females. Heterogeneity among studies was generally high and significant, although age at assessment was not a significant moderator of effect. Descriptive synthesis did not identify an obvious excess or deficiency of male-biased or female-biased effects for any trait category. Individual study quality was generally good, and we found no evidence of publication bias.

CONCLUSIONS

We found no evidence that the sexes differ in their susceptibility to the effects of severe or moderate prematurity/low birthweight on cognitive function, internalizing traits or externalizing traits. Result heterogeneity tended to be high, but this reflects that one sex is not consistently more affected than the other. Frequently stated generalizations that one sex is more susceptible to prenatal adversity should be re-evaluated.

Maternal age at childbirth and the risk of attention-deficit/hyperactivity disorder and learning disability in offspring

Background

Studies have shown that young maternal age at childbirth can increase the risk of attention-deficit/hyperactivity disorder (ADHD) in offspring, but a study of the U.S. population has not been reported. Moreover, there is no reported research on young and advanced maternal age at childbirth and whether it can contribute to the risk of learning disability (LD) in offspring.

Methods

This study evaluated the association between young and advanced maternal age at childbirth and offspring risk of ADHD and LD in the U.S. population. Using data from 8,098 participants included in the National Health and Nutrition Examination Survey (NHANES) conducted in 1999-2004, we analyzed the association between maternal age at childbirth and ADHD and LD risk in offspring. Odds ratios (ORs) and 95% confidence intervals (CIs) for maternal age at childbirth in association with ADHD and LD risk in offspring were estimated using multivariate logistic regression models after adjustment for age, sex, race, body mass index (BMI), poverty income ratio, smoking status during pregnancy, and NHANES cycle. Restricted cubic spline (RCS) models were used to evaluate potential non-linear relationships. Sensitivity analyses were performed to ensure the reliability of the results.

Results

Among all participants, the offspring of subjects with a maternal age at childbirth of 18-24 years had an increased risk of ADHD (OR = 1.34, 95% CI: 1.01, 1.79) and LD (OR = 1.36, 95% CI: 1.06, 1.79) or either ADHD or LD (OR = 1.48, 95% CI: 1.20, 1.81). Additionally, compared with subjects with a maternal age at childbirth of 25-29 years, subjects with a maternal age at childbirth of 35-39 years had lower odds of having offspring with ADHD (OR = 0.60, 95% CI: 0.36, 1.00) and higher odds of having offspring with LD (OR = 1.34, 95% CI: 1.01, 1.78). The relationship between maternal age at childbirth and LD risk presented a U-shaped curve.

Conclusions

These results provide epidemiological evidence showing that young and advanced maternal age at childbirth are associated with ADHD and LD risk.

Parent ratings on the MEMRY questionnaire predict children's academic performance

Given the high rates of learning challenges in children with medical conditions, efficient and reliable screening methods are crucial. This study examined whether parent report of daily learning and memory predicts academic achievement in youth. Parents of 213 youth (aged 6-18) with varied medical diagnoses completed the Multidimensional Everyday Memory Ratings for Youth (MEMRY), and youth completed subtests from the Wechsler Individual Achievement Test-Third Edition (WIAT-III) as part of a comprehensive assessment. All scales of the MEMRY (Learning, Daily Memory, Executive/Working Memory) correlated significantly with WIAT-III Spelling, Word Reading, and Numerical Operations, while only the MEMRY Learning subscale correlated significantly with WIAT-III Pseudoword Decoding. Regression analyses indicated that MEMRY Learning significantly predicted WIAT-III Word Reading and Spelling, while both the MEMRY Learning and MEMRY Daily Memory scales significantly predicted WIAT-III Numerical Operations. When Full Scale IQ was entered into the models first, the MEMRY Learning subscale accounted for an additional 4% of variance in WIAT-III Word Reading and 7% of variance in WIAT-III Spelling, but did not account for additional variance in WIAT-III Numerical Operations or Pseudoword Decoding. Analyses in a subset of children with broadly normal intellectual functioning demonstrated very similar results, with even higher variance in academic testing accounted for by the MEMRY. In sum, the MEMRY questionnaire may serve as an efficient screen to identify children at risk for reading, spelling, and math deficits.

Mathematical skills of 11-year-old children born very preterm and full-term

Preterm birth affects the academic development of children, especially in mathematics. Remarkably, only a few studies have measured specific effects of preterm birth on mathematical skills in primary school. The aim of this study was to compare 11-year-old children, with an IQ above 70, born very preterm (N = 64) and full-term (N = 72) on a variety of 5th grade mathematical skills and cognitive abilities important for mathematical learning. The measures were spontaneous focusing on numerosity (SFON), spontaneous focusing on quantitative relations (SFOR), arithmetic fluency, mathematics achievement, number line estimation, rational number magnitude knowledge, mathematics motivation, reading skills, visuospatial processing, executive functions, and naming speed. The children born very preterm and full-term differed in arithmetic fluency, SFON and SFOR. Domain general cognitive abilities did not fully explain the group differences in SFON and SFOR. Retrospective comparisons of the samples at the age of five years showed large group differences in early mathematical skills and cognitive abilities. Despite lower early mathematical skills, the children born very preterm reached peer equivalent performance in many mathematical skills by the age of 11 years. Nevertheless, they appear less likely to focus on implicit mathematical features in their everyday life.

Perinatal Factors Associated with Autism Spectrum Disorder in Jamaican Children

Mode of delivery, preterm birth, and low birth weight (LBW) are hypothesized to be associated with autism spectrum disorder (ASD) in the offspring. Using data from 343 ASD cases (2-8 years) and their age- and sex-matched typically developing controls in Jamaica we investigated these hypotheses. Our statistical analyses revealed that the parish of residence could modify the association between cesarean delivery and ASD, with a difference found in this relationship in Kingston parish [matched odds ratio (MOR) (95% confidence interval (CI)) 2.30 (1.17-4.53)] and other parishes [MOR (95% CI) 0.87 (0.48-1.59)]. Although the associations of LBW and preterm birth with ASD were not significant, we observed a significant interaction between LBW and the household socioeconomic status. These findings require replication.

The Prevalence of Specific Learning Disorder among School-going Children in Ernakulam District, Kerala, India: Ernakulam Learning Disorder (ELD) Study

BACKGROUND

Specific learning disorder (SLD) is a neurodevelopmental disorder characterized by impairment in reading, written expression, and mathematics. The government provides several educational and social benefits to students with SLD, hence, an accurate assessment of the prevalence of SLD is important. This study is an attempt to find the prevalence of SLD and its determinants among the school-going children in Ernakulam district, Kerala, India.

METHODS

School-going children from the fourth standard to the seventh standard were included in the study. Multistage stratified cluster sampling was used. The screening for SLD was done using the LD screening tool, and confirmation of the diagnosis was made using the NIMHANS index for SLD and Malin's Intelligence Scale for Indian Children (MISIC).

RESULTS

The prevalence of SLD was 16.49% (95% CI =14.59-18.37). The prevalence of impairment in reading, written expression, and mathematics was 12.57%, 15.6%, and 9.93%, respectively. Binary logistic regression analysis showed that male gender, low birth weight, presence of developmental delay, family history of poor scholastic performance, and syllabus were independently associated with SLD.

CONCLUSIONS

The study found a higher prevalence of SLD (16.49%) and certain modifiable determinants of SLD were identified. It highlights the need for early detection and remedial measures for children with SLD.

Exposure to Ambient Particulate Matter during Specific Gestational Periods Produces Adverse Obstetric Consequences in Mice

BACKGROUND

Epidemiological studies associate inhalation of fine-sized particulate matter (PM_2.5) during pregnancy with preterm birth (PTB) and low birth weight (LBW) but disagree over which time frames are most sensitive, or if effects are cumulative.

OBJECTIVES

Our objective was to provide experimental plausibility for epidemiological observations by testing the hypothesis that exposure to PM_2.5 during discrete periods of pregnancy results in PTB and LBW.

METHODS

For the first study, timed-pregnant B6C3F1 mice were exposed to concentrated ambient PM_2.5 (CAPs) or filtered air (FA) throughout pregnancy [6 h/d from gestational day (GD) 0.5 through GD16.5]. A follow-up study examined the effects of CAPs exposure during discrete gestational periods (1: GD0.5–5.5; 2: GD6.5–14.5; 3: GD14.5–16.5; 4: GD0.5–16.5) aligning to milestones during human development.

RESULTS

In the first experiment, exposure to 160 μg CAPs/m³ throughout pregnancy decreased gestational term by 0.5 d (∼1.1  wk decrease for humans) and birth weight by 11.4% compared with FA. The follow-up experiment investigated timing of CAPs exposure (mean concentrations at 178, 193, 171, and 173 μg/m³ for periods 1–4, respectively). Pregnancy was significantly shortened (vs. FA) by ∼0.4d when exposure occurred during gestational periods 2 and 4, and by ∼0.5d if exposure occurred during period 3. Exposure during periods 1, 2, and 4 reduced birth weight by ∼10% compared with FA, and placental weight was reduced (∼8%) on GD17.5 if exposure occurred only during period 3.

CONCLUSIONS

Adverse PM_2.5-induced outcomes such as PTB and LBW are dependent upon the periods of maternal exposure. The results of these experimental studies could contribute significantly to air pollution policy decisions in the future. https://doi.org/10.1289/EHP1029.

Associations between the duration of active commuting to school and academic achievement in rural Chilean adolescents

Background

Habitual active commuting to school may be positively associated with academic achievement. The aim of this study was to examine the relationship between duration of walking or otherwise actively commuting to school and academic achievement.

Methods

This cross-sectional study included 389 adolescents from seven rural schools (12–13 years). Mode and duration of active commuting to school (use of active means such as walking or biking to and from school) and screen time were self-reported. Academic achievement was determined by the outcome in basic grades (language and mathematics).

Results

Active commuting to school was not associated with higher scores in any grades after adjustment for potential confounders. No evidence was found of interactions between gender and academic achievement, but there was interaction with duration of walking (<30 min, 30–60 min, and >60 min). Adjusted binary logistic regression analysis suggested that adolescents who spent between 30 and 60 min actively commuting were more likely to obtain high academic achievement (language and mathematics).

Conclusions

Thirty to 60 min of ACS may have a positive influence on academic achievement in adolescents, so, it is necessary to make recommendations for the children to walk from and/or to school. This could help society to recognize the relevance of physical activity to health as well as to academic performance.

Research Review: Environmental exposures, neurodevelopment, and child mental health - new paradigms for the study of brain and behavioral effects

BACKGROUND

Environmental exposures play a critical role in the genesis of some child mental health problems.

METHODS

We open with a discussion of children's vulnerability to neurotoxic substances, changes in the distribution of toxic exposures, and cooccurrence of social and physical exposures. We address trends in prevalence of mental health disorders, and approaches to the definition of disorders that are sensitive to the subtle effects of toxic exposures. We suggest broadening outcomes to include dimensional measures of autism spectrum disorders, attention-deficit hyperactivity disorder, and child learning capacity, as well as direct assessment of brain function.

FINDINGS

We consider the impact of two important exposures on children's mental health: lead and pesticides. We argue that longitudinal research designs may capture the cascading effects of exposures across biological systems and the full-range of neuropsychological endpoints. Neuroimaging is a valuable tool for observing brain maturation under varying environmental conditions. A dimensional approach to measurement may be sensitive to subtle subclinical toxic effects, permitting the development of exposure-related profiles and testing of complex functional relationships between brain and behavior. Questions about the neurotoxic effects of chemicals become more pressing when viewed through the lens of environmental justice.

CONCLUSIONS

Reduction in the burden of child mental health disorders will require longitudinal study of neurotoxic exposures, incorporating dimensional approaches to outcome assessment, and measures of brain function. Research that seeks to identify links between toxic exposures and mental health outcomes has enormous public health and societal value.

Aerobic capacity as a mediator of the influence of birth weight and school performance

Low birth weight is associated with cognitive impairments persisting into adolescence and early adulthood. The purposes of this study was two-fold: to analyse the association between birth weight (BW) and school performance, and to determine the influence of adolescent aerobic capacity and muscular strength on the association between BW and school performance in children at 12-13 years. The study included 395 children (50.4% boys, aged 12-13 years). Self-reported BW was evaluated. We measured school performance (mean of the grades obtained in language and mathematics) and two physical fitness tests (aerobic capacity and muscular strength). Analysis of variance was used to analyse the differences in school performance according to BW categories (⩽2500, 2500-3500 and ⩾3500 g). Linear regression models fitted for mediation analyses examined whether the association between BW and school performance was mediated by aerobic capacity and/or muscular strength. Higher BW was associated with better school performance independent of current body mass index. These differences disappeared after controlling for aerobic capacity, which also mediated the association between BW and school performance (13.4%). The relationship between BW and school performance seems to be dependent on aerobic capacity fitness. Our results are of importance because the consequences of BW tend to continue into childhood, and current physical fitness of the children may potentially be modified to improve school performance.

The Effects of Low Birth Weight on School Performance and Behavioral Outcomes of Elementary School Children in Oman

OBJECTIVES

Our study aimed to examine the effects of low birth weight (LBW) on the school performance and behavior of elementary school children in Oman. .

METHODS

Data were gathered through a cross-sectional survey of nine elementary schools from the Muscat and A'Dhahirah regions. The study utilized a unique database created by linking information from the children's health cards and current academic and behavioral performance records. Information on children's performance in various areas such as language, mathematics, science, information technology, sports, and behavior were obtained from the school registers. Birth weight (BW) and selected sociodemographic data were obtained from the copy of their health cards kept by each school. A total of 542 elementary school children aged 7-11 years, who had completed grades 2-4, were surveyed.  .

RESULTS

Data from the school register revealed a very high rate (17.7%) of LBW and, overall, 12% of the children exhibited below average performance on selected outcome measures. The below average school performance varied from 5-17% across the six selected areas of school performance. The highest rate of below average performance was observed in science (17%), followed by arithmetic and language (16% each). BW showed significant differential effects on school performance and behavioral outcomes, which remained significant after controlling for the effect of potential confounders. It was found that LBW children were 2-6 times more likely to have poorer school performance in all areas than their normal BW peers. .

CONCLUSION

Early intervention programs or special care for LBW children in school could be an effective means of improving educational outcomes and the behavior of these children. Attempts should be made to reduce or prevent poor pregnancy outcomes, which, in turn, would reduce the cost of the health, education, and social services systems.

Independent and combined influence of neonatal and current body composition on academic performance in youth: The UP & DOWN Study

BACKGROUNDS

Unhealthy body composition is a cause for concern across the lifespan.

OBJECTIVE

The objective of this study was to examine the independent and combined associations between neonatal and current body composition with academic performance among youth.

METHODS

This cross-sectional study was conducted with a total of 1557 youth (745 girls) aged 10.4 ± 3.4 years. Birth weight and length at birth were self-reported. Current body composition was assessed by body mass index (BMI), waist circumference (WC) and percentage of body fat (BF%). Academic performance was assessed through schools records.

RESULTS

Birth weight was related to all academic variables in boys, independent of potential confounders, including BMI; whereas WC, BMI and BF% were related to all academic performance indicators in both boys and girls, independent of potential confounders, including birth weight (all P < 0.05). In addition, the combined adverse effects of low birth weight and current overweight on academic performance were observed in both boys and girls for grade point average (GPA) indicator. Boys in the group with none adverse effect had significantly higher scores in GPA (score +0.535; 95% confidence interval, 0.082-0.989) than boys in the group of both adverse effects (P < 0.007); among girls, GPA score was higher in the group with none adverse effect than in the groups with one or two adverse effects (P for trend = 0.029).

CONCLUSIONS

Neonatal and current body composition, both independently and combined, may influence academic performance in youth.

Physical, behavioral, and cognitive effects of prenatal tobacco and postnatal secondhand smoke exposure

The purpose of this review is to examine the rapidly expanding literature regarding the effects of prenatal tobacco and postnatal secondhand smoke (SHS) exposure on child health and development. Mechanisms of SHS exposure are reviewed, including critical periods during which exposure to tobacco products appears to be particularly harmful to the developing fetus and child. The biological, biochemical, and neurologic effects of the small fraction of identified components of SHS are described. Research describing these adverse effects of both in utero and childhood exposure is reviewed, including findings from both animal models and humans. The following adverse physical outcomes are discussed: sudden infant death syndrome, low birth weight, decreased head circumference, respiratory infections, otitis media, asthma, childhood cancer, hearing loss, dental caries, and the metabolic syndrome. In addition, the association between the following adverse cognitive and behavioral outcomes and such exposures is described: conduct disorder, attention-deficit/hyperactivity disorder, poor academic achievement, and cognitive impairment. The evidence supporting the adverse effects of SHS exposure is extensive yet rapidly expanding due to improving technology and increased awareness of this profound public health problem. The growing use of alternative tobacco products, such as hookahs (a.k.a. waterpipes), and the scant literature on possible effects from prenatal and secondhand smoke exposure from these products are also discussed. A review of the current knowledge of this important subject has implications for future research as well as public policy and clinical practice.

Neurodevelopmental outcomes of infants born prematurely

Long-term follow-up of infants born prematurely is necessary to determine neurodevelopmental outcomes, particularly with the expansion of interest from major disabilities to high prevalence/low severity dysfunctions. Models of pathogenesis include changes due to developmental disruptions and to injury, the magnitude and type of change influenced by the infant's age, and central nervous system recovery and reorganization. Alterations in neurogenesis, migration, myelination, cell death, and synaptogenesis occur even in the absence of insult. Despite increased knowledge regarding these processes, the functional significance of brain abnormalities is unclear. Because of methodologic problems in follow-up studies, it is difficult to characterize outcome definitively. Nonetheless, an acceptable degree of agreement across studies is found with regard to specific neurodevelopmental outcomes: motor/neurologic function, visuomotor integrative skills, IQ, academic achievement, language, executive function, and attention-deficit hyperactivity disorder/behavioral issues. In general, children born prematurely have more problems in these areas than do their normal birth weight counterparts. Suggestions for improved analyses and clarification of outcomes include use of cluster analysis, structural equation modeling, growth curve analysis, developmental epidemiologic approaches, and better control of background variables using risk indexes and factor scores. Better assessment techniques measuring functions documented to be at higher risk of problems are discussed.

Sex differences in cerebral blood flow following chorioamnionitis in healthy term infants

OBJECTIVE

Sex is an important determinant of neonatal outcomes and may have a significant role in the physiologic response to maternal chorioamnionitis. Our goal was to determine cerebral blood flow (CBF) parameters by sex and subsequent neurodevelopment in healthy term infants exposed to chorioamnionitis.

STUDY DESIGN

CBF by Doppler ultrasound in anterior and middle cerebral (ACA, MCA) and basilar arteries were analyzed for time-averaged maximum velocity (TAMX) and corrected resistive index in 52 term control and chorioamnionitis-exposed infants between 24 and 72 h after birth. Placental pathology confirmed histologic evidence of chorioamnionitis (HC). Bayley Scales of Infant Development-III were administered at 12 months.

RESULT

HC male infants had significantly greater TAMX in the MCA and lower mean MCA and ACA resistance than HC females. Abnormal CBF correlated negatively with neurodevelopmental outcome.

CONCLUSION

CBF is altered in term infants with histologically confirmed chorioamnionitis compared with control infants with sex-specific differences.

Housing and child health

The connection between housing and health is well established. Physical, chemical, and biological aspects of the child's home, such as cleanliness, moisture, pests, noise, accessibility, injury risks, and other forms of housing environmental quality, all have the potential to influence multiple aspects of the health and development of children. Basic sanitation, reduced household crowding, other improvements in housing and expanded, and improved housing regulations have led to advances in children's health. For example, lead poisoning prevention policies have profoundly reduced childhood lead exposure in the United States. This and many other successes highlight the health benefits for families, particularly children, by targeting interventions that reduce or eliminate harmful exposures in the home. Additionally, parental mental health problems, food insecurity, domestic violence, and the presence of guns in children's homes all are largely experienced by children in their homes, which are not as yet considered part of the Healthy Homes agenda. There is a large movement and now a regulatory structure being put in place for healthy housing, which is becoming closely wedded with environmental health, public health, and the practice of pediatrics. The importance of homes in children's lives, history of healthy homes, asthma, and exposures to lead, carbon monoxide, secondhand/thirdhand smoke, radon, allergy triggers is discussed, as well as how changes in ambient temperature, increased humidity, poor ventilation, water quality, infectious diseases, housing structure, guns, electronic media, family structure, and domestic violence all affect children's health.

Motor and speech disorders in classic galactosemia

Purpose To test the hypothesis that children with classic galactosemia and speech disorders are at risk for co-occurring strength and coordination disorders. Method This is a case-control study of 32 children (66% male) with galactosemia and neurologic speech disorders and 130 controls (50% male) ages 4-16 years. Speech was assessed using the Percentage of Consonants Correct (PCC) metric from responses to the Goldman-Fristoe Test of Articulation-2 and from a 5-min recorded speech sample, hand and tongue strength using the Iowa Oral Performance Instrument, and coordination using the Movement Assessment Battery for Children. The number of days on milk during the neonatal period was obtained by parent report. Analyses of covariance, distributions, and correlations were used to evaluate relationships among speech, strength, coordination, age, gender, and days on milk. Results Children with galactosemia had weaker hand and tongue strength and most (66%) had significant coordination disorders, primarily affecting balance and manual dexterity. Among children with galactosemia, children with more speech errors and classified as childhood apraxia of speech (n = 7) and ataxic dysarthria (n = 1), had poorer balance and manual dexterity, but not weaker hand or tongue strength, compared to the children with fewer speech errors. The number of days on milk during the neonatal period was associated with more speech errors in males but not in females. Conclusion Children with galactosemia have a high prevalence of co-occurring speech, coordination, and strength disorders, which may be evidence of a common underlying etiology, likely associated with diffuse cerebellar damage, rather than distinct disorders.

The effect of low birth weight on height, weight and behavioral outcomes in the medium-run

A number of studies have documented negative long term effects of low birth weight. Yet, not much is known about the dynamics of the process leading to adverse health and educational outcomes in the long run. While previous studies focusing mainly on LBW effects on physical growth and cognitive outcomes have found effects of the same size at both school age and young adulthood, others have found a diminishing negative effect over time. The purpose of this paper was to bring new evidence to this issue by analyzing the medium run effects of low birth weight on child behavioral outcomes as well as physical growth at ages 6 months, 3, 7 and 11 years using data from the Danish Longitudinal Survey of Children. Observing the same children at different points in time enabled us to chart the evolution of anthropometric and behavioral deficits among children born with low birth weight and helped understanding the nature and timing of interventions.

Obstetric factors and different causes of special educational need: retrospective cohort study of 407,503 schoolchildren

OBJECTIVE

To determine whether relationships with gestational age and birthweight centile vary between specific causes of special educational need (SEN).

DESIGN

Retrospective cohort study.

SETTING

Scotland.

POPULATION

A cohort of 407,503 schoolchildren.

METHODS

Polytomous logistic regression was used to examine the risk of each cause of SEN across the spectrum of gestation at delivery and birthweight centile, adjusting for potential confounding factors.

MAIN OUTCOME MEASURES

Crude and adjusted odds ratios and confidence intervals.

RESULTS

Of the 19,821 children with SEN, 557 (2.8%) had sensory impairments, 812 (4.1%) had physical or motor disabilities, 876 (4.4%) had language impairments, 2823 (14.2%) had social, emotional, or behavioural problems, 7018 (35.4%) had intellectual disabilities, 4404 (22.2%) had specific learning difficulties, and 1684 (8.5%) autistic spectrum disorder (ASD). Extreme preterm delivery (at 24-27 weeks of gestation) was a strong predictor of sensory (adjusted OR 23.64, 95% CI 12.03-46.45), physical or motor (adjusted OR 29.69, 95% CI 17.49-50.40), and intellectual (adjusted OR 11.67, 95% CI 8.46-16.10) impairments, with dose relationships across the range of gestation. Similarly, birthweight below the third centile was associated with sensory (adjusted OR 2.85, 95% CI 2.04-3.99), physical or motor (adjusted OR 2.47, 95% CI 1.82-3.37), and intellectual (adjusted OR 2.67, 95% CI 2.41-2.96) impairments. Together, gestation and birthweight centile accounted for 24.0% of SEN arising from sensory impairment, 34.3% arising from physical or motor disabilities, and 26.6% arising from intellectual disabilities. Obstetric factors were less strongly associated with specific learning difficulties and social or emotional problems, and there were no significant associations with ASD.

CONCLUSIONS

The association between gestation and birthweight centile and overall risk of SEN is largely driven by very strong associations with sensory, physical or motor impairments, and intellectual impairments.

Advanced parental ages and low birth weight in autism spectrum disorders--rates and effect on functioning

OBJECTIVES

(1) To assess the distribution of parental age and birth weight in a large cohort with autism spectrum disorder (ASD) and to compare them to Israeli national data. (2) To examine possible relationships between these risk factors and functioning.

METHODS

The study included 529 participants diagnosed with ASD using standardized tests: the Autism Diagnosis Interview-Revised and the Autism Diagnosis Observation Schedule (ADOS). Medical, developmental and familial histories (gender, age, pregnancy and birth information, parental ages) were obtained. Autism severity was assessed using the new ADOS severity scale and adaptive skill using the Vineland Adaptive Behavior Scales.

RESULTS

Advanced parental age was associated with ASD. In the older age range the percentages of mothers (35-44 y) and fathers (30-40 y) were significantly higher in the ASD cohort in comparison to the Israeli newborn data. The ASD cohort had significantly higher percentages of low birth weight (<2500 g) and very low birth weight (VLBW<1500 g) in comparison to the Israeli newborn data. Of these risk factors, only VLBW was associated with lower adaptive functioning. The group with VLBW had lower scores in daily living, socialization and motor skills in comparison to the >1500 g group. Autism severity was not associated with advanced parental age or VLBW.

CONCLUSIONS

The shift in parental age distribution and birth weight in our ASD cohort suggests that the increase in ASD prevalence in recent years might be associated with novel prenatal insults. An adverse fetal course resulting in VLBW may represent a "second hit" phenomenon, causing a poorer outcome.

Perinatal and neonatal risk factors for autism: a comprehensive meta-analysis

BACKGROUND

The etiology of autism is unknown, although perinatal and neonatal exposures have been the focus of epidemiologic research for over 40 years.

OBJECTIVE

To provide the first review and meta-analysis of the association between perinatal and neonatal factors and autism risk.

METHODS

PubMed, Embase, and PsycInfo databases were searched for studies that examined the association between perinatal and neonatal factors and autism through March 2007. Forty studies were eligible for the meta-analysis. For each exposure, a summary effect estimate was calculated using a random-effects model. Heterogeneity in effect estimates across studies was examined, and, if found, a meta-regression was conducted to identify measured methodological factors that could explain between-study variability.

RESULTS

Over 60 perinatal and neonatal factors were examined. Factors associated with autism risk in the meta-analysis were abnormal presentation, umbilical-cord complications, fetal distress, birth injury or trauma, multiple birth, maternal hemorrhage, summer birth, low birth weight, small for gestational age, congenital malformation, low 5-minute Apgar score, feeding difficulties, meconium aspiration, neonatal anemia, ABO or Rh incompatibility, and hyperbilirubinemia. Factors not associated with autism risk included anesthesia, assisted vaginal delivery, postterm birth, high birth weight, and head circumference.

CONCLUSIONS

There is insufficient evidence to implicate any 1 perinatal or neonatal factor in autism etiology, although there is some evidence to suggest that exposure to a broad class of conditions reflecting general compromises to perinatal and neonatal health may increase the risk. Methodological variations were likely sources of heterogeneity of risk factor effects across studies.

The role of imprinted genes in mediating susceptibility to neuropsychiatric disorders

Imprinted genes, which are thought to comprise <1% of the mammalian genome, are defined by their parent-of-origin specific monoallelic expression arising as a consequence of differential epigenetic marking of alleles in the paternal and maternal germlines. Such genes are highly represented in the brain and placental transcriptomes, and have been shown to exert significant influence on fundamental developmental processes in these organs. Converging evidence from work in man and animal models has shown that imprinted genes can influence a variety of brain and behavioral endophenotypes. In this article, we review the current evidence that imprinted gene dysfunction is associated with vulnerability to several common psychiatric disorders. We also discuss how studying imprinted gene (dys)function may provide mechanistic insights into two important areas in modern psychiatry: first, how environmental factors (especially in utero) interact with genetic liability via epigenetic mechanisms to predispose to later mental illness, and second, the molecular underpinnings of sex-specific vulnerability to psychiatric disorders.

Individual-learning ability predicts social-foraging strategy in house sparrows

Social foragers can use either a 'producer' strategy, which involves searching for food, or a 'scrounger' strategy, which involves joining others' food discoveries. While producers rely on personal information and past experience, we may ask whether the tendency to forage as a producer is related to being a better learner. To answer this question, we hand-raised house sparrow (Passer domesticus) nestlings that upon independence were given an individual-learning task that required them to associate colour signal and food presence. Following the testing phase, all fledglings were released into a shared aviary, and their social-foraging tendencies were measured. We found a significant positive correlation between individual's performance in the individual-learning task and subsequent tendency to use searching (producing) behaviour. Individual-learning score was negatively correlated with initial fear of the test apparatus and with body weight. However, the correlation between individual learning and searching remained significant after controlling for these variables. Since it was measured before the birds entered a social group, individual-learning ability could not be the outcome of being a producer. However, the two traits may be initially associated, or individual learning could facilitate producing behaviour. To our knowledge, this is the first evidence that associates individual-learning abilities with social-foraging strategies in animal groups.

Prenatal stress and brain development

Prenatal stress (PS) has been linked to abnormal cognitive, behavioral and psychosocial outcomes in both animals and humans. Animal studies have clearly demonstrated PS effects on the offspring's brain, however, while it has been speculated that PS most likely affects the brains of exposed human fetuses as well, no study has to date examined this possibility prospectively using an independent stressor (i.e., a stressful event that the pregnant woman has no control over, such as a natural disaster). The aim of this review is to summarize the existing animal literature by focusing on specific brain regions that have been shown to be affected by PS both macroscopically and microscopically. These regions include the hippocampus, amygdala, corpus callosum, anterior commissure, cerebral cortex, cerebellum and hypothalamus. We first discuss the mechanisms by which the effects of PS might occur. In particular, we show that maternal and fetal hypothalamic-pituitary-adrenal (HPA) axes, and the placenta, are the most likely candidates for these mechanisms. We see that, although animal studies have obvious advantages over human studies, the integration of findings in animals and the transfer of these findings to human populations remains a complex issue. Finally, we show how it is possible to circumvent these challenges by studying the effects of PS on brain development directly in humans, by taking advantage of natural or man-made disasters and assessing the impact and consequences of such stressful events on pregnant women and their offspring prospectively.

Preventing low birthweight through maternal multiple micronutrient supplementation: a cluster-randomized, controlled trial in Indramayu, West Java

BACKGROUND

Micronutrient deficiencies may contribute to a higher incidence of low birthweight (LBW). UNICEF/United Nations University/World Health Organization jointly proposed a formulation for a multiple micronutrient supplement for pregnant women, and several effectiveness trials were conducted to assess its impact.

OBJECTIVE

To evaluate the efficacy of prenatal multiple micronutrient supplementation for improving birth size, pregnancy outcome, and maternal micronutrient status in comparison with iron-folic acid supplementation.

METHODS

We carried out a cluster-randomized, controlled trial in Indramayu, Indonesia, involving 843 pregnant women. Of these, 432 received multiple micronutrients and 411 received iron-folic acid. Fieldworkers visited the women daily to observe supplement consumption and record fetal loss and mortality.

RESULTS

The mean number of supplements consumed during pregnancy and 30 days postpartum was high (136 in the group receiving multiple micronutrients and 140 in the iron-folic acid group). The women consumed the supplements on average 5 days per week. Although there were no significant differences between the groups in the percentage of infants with LBW there was a trend toward a lower incidence of LBW in the group receiving multiple micronutrients (6.3% vs. 7.3%), and the mean birthweight was 40 g higher in the group receiving multiple micronutrients than in the iron-folic acid group, although the difference was not significant. Among those who consumed 90 or more supplements during pregnancy, women taking multiple micronutrients had a 3.3% combined rate of miscarriage, stillbirth, or neonatal death, as compared with 6.9% for those taking iron-folic acid only (p < .049). The anemia rates in the two groups were similar after supplementation, even though the amount of iron in the multiple micronutrient supplement was half that in the iron-folic acid supplement. Serum retinol was higher in the group receiving multiple micronutrients.

CONCLUSIONS

Multivitamin supplementation use among pregnant women is as effective as iron-folic acid in improving anemia status and appears to have other benefits for maternal and child nutritional status.

Prenatal ultrasound exposure and children's school performance at age 15-16: follow-up of a randomized controlled trial

OBJECTIVE

To evaluate the association between prenatal ultrasound exposure and school performance at 15-16 years of age.

METHODS

The study population consisted of children born to women who participated in a randomized controlled trial on the second-trimester ultrasound examination in Sweden from 1985 to 1987. Information about the children's grades when graduating from primary school and information on socioeconomic factors was obtained from Swedish nationwide registers. Comparisons were made using linear and logistic regression analyses according to randomization to ultrasound, ultrasound exposure in the second trimester and ultrasound exposure at any time during pregnancy. Boys and girls were analyzed separately.

RESULTS

Of the 4756 singleton children from the randomized trial, we identified 4458 (94%) in the National School Register. There were no statistically significant differences in school performance for boys or girls according to randomization or exposure to ultrasound in the second trimester. Compared to those who were unexposed, boys exposed to ultrasound at least once at any time during fetal life had a tendency towards lower mean school grades in general (-4.39 points; 95% CI, -9.59 to 0.81 (max possible, 320) points) and in physical education (-0.45 points; 95% CI, -0.91 to 0.01 (max possible, 20) points), but the differences did not reach significance.

CONCLUSION

In general, routine ultrasound examination in the second trimester had no effect on overall school performance in teenagers.

Early school-based learning difficulties in children born very preterm

BACKGROUND

Educational underachievement is a major morbidity associated with very preterm (VPT) birth. However, few studies have examined early school outcomes with most employing global, clinic based measures.

OBJECTIVE

To examine the early school achievement in a cohort of children born VPT and studied to age 6 years.

METHODS

A regional cohort of 102 VPT children (</=33 weeks GA) were followed prospectively alongside a comparison group of 108 full term (FT) children born during the same period (1998-2000). At 6 years corrected age, all children underwent a comprehensive neurodevelopmental evaluation that included the Woodcock-Johnson Tests of Achievement (WJ-III), teacher report and national numeracy and literacy test results. Rates of specific learning disabilities (LD) were also examined.

RESULTS

VPT children performed less well than FT children on WJ-III subtests (ps<.05), national tests (ps<.01), and in all curricular areas rated by teachers (ps<.01) except expressive language. Even VPT children without severe neurodevelopmental impairment scored lower on the WJ-III math, national tests (ps<.05) and were 2-3 times more likely to show delays (ps<.02) in math (43% vs. 19%), written language (36% vs. 22%), language comprehension (26% vs. 14%), handwriting (36% vs. 17%), spelling (38% vs. 30%) and physical education (33% vs. 11%). They were also twice as likely as FT children to have math LD (47% vs. 21%).

CONCLUSIONS

By age 6, a substantial proportion of VPT children are lagging behind their FT peers across multiple curriculum areas, with difficulties being most prominent in math. Findings highlight the need for early identification and educational supports to help maximise VPT children's learning opportunities during the transition to school.

Early working memory in children born with extremely low birth weight: assessed by object permanence

Object permanence is considered the earliest method for assessing working memory. Factors affecting object permanence performance in a sample of two hundred and thirty-three 18- to 22-month olds born with extremely low birth weight were examined. It was hypothesized that object permanence would be directly related to emotional and attention regulation, that children with lower birth weight and higher illness severity would have more difficulty on the object permanence task, and that no ethnic/racial differences would be found, as this is considered a culturally unbiased task. Attainment of object permanence had a significant positive association with emotional and attention regulation, even after controlling the medical severity and socioeconomic factors. More girls than boys passed the object permanence items. There was no ethnic/racial difference on object permanence. Our findings indicate that object permanence may be a culturally fair way of assessing development, and emotional and attention regulation are potential avenues of intervention for such skill.

Weight concerns in male low birth weight adolescents: relation to body mass index, self-esteem, and depression

OBJECTIVE

To compare weight concerns and self-reported body mass index (BMI) of low birth weight (LBW) adolescent boys to those of a normative sample and examine relationships among BMI, weight concerns, self-esteem, and depression in the LBW cohort.

METHODS

LBW boys (n = 260; mean age, 16.0) belong to the Neonatal Brain Hemorrhage Study birth cohort. Normative boys (n = 305; mean age, 16.5) belong to the National Health and Nutrition Examination Survey. Both samples were assessed in 2001-2004 with self-report questionnaires. BMI was calculated from self-reported height and weight. Weight perception and weight dissatisfaction were assessed with the Eating Symptoms Inventory. In LBW boys, self-esteem was measured with the Rosenberg Self-Esteem Scale and depression with the Beck Depression Inventory.

RESULTS

Based on self-reported height and weight, LBW boys were more likely to be healthy weight or underweight and less likely to be overweight than normative boys. Despite having healthier self-reported BMIs, LBW boys reported more weight concerns than the normative sample. A total of 46.9% of LBW boys perceived their weight as abnormal, and 76.5% desired weight change. Weight concerns in LBW boys mostly reflected a perception of being underweight (31.2% of the cohort) and a desire to gain weight (47.5% of the cohort), although only 6.5% were clinically underweight. Weight concerns, but not BMI, were related to clinical depression and lower self-esteem.

CONCLUSIONS

LBW adolescent boys are at high risk of experiencing weight concerns. Weight concerns rather than BMI are associated with emotional problems in LBW boys.

Health and the educational attainment of adolescents: evidence from the NLSY97

This article examines the mechanisms linking health to the educational attainment of adolescents. In particular it investigates the role of cognitive/academic achievement and a variety of psychosocial adjustment factors in explaining this relationship. Using data from the National Longitudinal Survey of Youth 1997 cohort (NLSY97), we estimate models of timely high school completion and of post-secondary enrollment using both standard logit estimation and sibling fixed-effects models. We find that, net of sociodemographic background and stable unobserved family characteristics, adolescents who experience worse health are substantially less likely to complete high school by their 20th birthday and to transition to post-secondary education. Cognitive/academic achievement and psychosocial factors appear to explain a large portion of these health-related educational deficits. However adolescent health continues to be significantly associated with these key educational transitions. The findings highlight a potentially important role of health selection processes in generating socioeconomic inequalities in early adolescence to young adulthood.

School performance of adolescents born preterm: neuropsychological and background correlates

In this longitudinal study the development of preterm and control children was followed from infancy until adolescence. School performance at the age of 16 in subjects born very preterm with a gestational age (GA) of <or= 32 weeks was compared with the performance of adolescents born full-term. None of the subjects had major disabilities. The study groups performed similarly in most school subjects, including mathematics, the second foreign language and the native language (Finnish). Subjects in the preterm group achieved significantly higher grade points in the first foreign language than control subjects. In particular, the difference was evident between the preterm and control boys. The extremely preterm group with a GA <or= 29 weeks did not differ from the more mature group with a GA between 30 and 32 weeks in terms of the school grade points. Verbal and performance scale IQs as assessed at the age of 9 were of primary importance in predicting school success in adolescence. The results suggest a good outcome, measured by school grade scores at 16 years of age, of the subjects born very preterm.

Understanding language and cognitive deficits in very low birth weight children

Very-low-birth-weight infants are at much higher risk for cognitive and language delays but the nature of such deficits is not clearly understood. Given increasing rates of prematurity and infants born very-low-birth-weight, examination of mechanisms that underlie poorer developmental outcome is essential. We investigated language and cognitive abilities in very-low and normal birth-weight infants to determine whether performance differences were due to poorer global cognitive performance or to deficits in specific processing abilities. Thirty-two very-low and 32 normal birth-weight infants received visual and auditory-visual habituation recognition-memory tasks, and standardized language and cognitive assessments. Very-low-birth-weight infants performed more poorly on visual and auditory-visual habituation tasks and scored lower than controls on cognitive and language measures. These findings suggest that differences in language abilities in very-low-birth-weight children may be part of a global deficit that impacts many areas of cognitive functioning rather than a specific impairment in rapid auditory processing.

Prenatal tobacco smoke and postnatal secondhand smoke exposure and child neurodevelopment

PURPOSE

To review the recent scientific literature examining the association of prenatal tobacco and postnatal secondhand smoke exposure and child neurodevelopment.

RECENT FINDINGS

Low birth weight and decreased in-utero brain growth are two of multiple potential etiologic pathways proposed as mediating the effects of prenatal tobacco smoke exposure on child neurodevelopment. These negative effects of prenatal exposure have been consistently demonstrated in animal models, and in humans have been found as early as the newborn period. The literature on both prenatal and postnatal exposure is remarkably consistent in showing associations with increased rates of behavior problems, including irritability, oppositional defiant behavior, conduct disorders and attention deficit hyperactivity disorder. A more rudimentary literature also suggests deficits in intelligence quotient. Recent studies have focused on elucidating the complex interaction among tobacco exposure, genetics and environmental factors. Questions still remain about the relative roles of prenatal vs. postnatal exposure and the potential role of genetic and social confounders, limiting the ability to infer a causal nature to these associations at this time. The consistency of findings across studies is, however, highly suggestive of a causal relationship between environmental tobacco exposure and adverse behavioral and cognitive outcomes in children.

SUMMARY

Prenatal tobacco and postnatal secondhand smoke exposure is consistently associated with problems in multiple domains of children's neurodevelopment and behavior.

Prenatal Multiple Micronutrient Supplementation has Greater Impact on Birthweight than Supplementation with Iron and Folic Acid: A Cluster-Randomized, Double-Blind, Controlled Programmatic Study in Rural Niger

Background

Micronutrient deficiencies during pregnancy are associated with adverse pregnancy outcomes, including reduced birthweight. Low birthweight is associated with increased risk of infant mortality and growth failure.

Objectives

To assess the effects of prenatal supplementation with UNIMMAP (United Nations International Multiple Micronutrient Preparation) compared with iron/folic acid on average birthweight and incidence of low birthweight.

Methods

Pregnant women from 78 villages in Niger were included in a cluster-randomized, double-blinded, controlled supplementation trial. Baseline, monthly follow-up, and birth data were collected. Cluster analysis was conducted to assess differences in mean birthweight and incidence of low birthweight between groups using multiple linear regression models. Analyses were stratified by nutrition status and duration of supplementation.

Results

Of the 3,670 women recruited, 2,550 completed the study and provided complete birthweight data (1,328 received multiple micronutrients and 1,222 received iron/folic acid). Mean birthweight was significantly higher (67 g, p < .001) with multiple micronutrients (3,092 ± 190 g) than with iron/folic acid (3,025 ± 205 g); this corresponded to a 14% fall in the incidence of low birthweight (from 8.4% with multiple micronutrients to 7.2% with folic acid fortification). The impact of multiple micronutrients was greater when the supplements were taken for more than 150 days. The incidence of low birthweight was further reduced in women who entered pregnancy with a poorer nutrition status.

Conclusions

Prenatal supplementation with multiple micronutrients had a greater positive impact on birthweight than supplementation with iron/folic acid. Our data suggest that prenatal supplementation with multiple micronutrients as part of a prenatal care package in addition to interventions to promote improved maternal prepregnancy nutrition status is an important strategy to increase birthweight and reduce the incidence of low birthweight.

Phonology, rapid naming and academic achievement in very preterm children at eight years of age

AIM

To examine the impact and additive effect of phonology and rapid naming deficits on reading, spelling and mathematics achievement in a group of very preterm children at 8 years of age.

METHODS

All surviving children with a gestational age less than 30 weeks, admitted to the neonatal intensive care unit at Royal Prince Alfred Hospital, in 1994 and 1995, were prospectively enrolled in developmental follow-up. Children with a neurosensory disability or a low intelligence score (FSIQ<or=85 points) were excluded. At 8 years of age standardised psychometric measures of cognition, linguistic ability and academic achievement were administered to a sample of 63 children.

RESULTS

Twenty-four (38.1%) children showed low achievement in reading, spelling or mathematics. Of these, 18 (75%) children showed low achievement in reading. Reading achievement was significantly correlated to phonological awareness, rapid naming and expressive vocabulary. Children with phonological awareness and rapid naming deficits showed significantly more delay in reading than children without such deficits. Children who had rapid naming deficits were more likely to show multiple skill delays. Rapid naming showed significant, though modest correlations with immaturity and illness variables. Maternal education was significantly associated with achievement.

CONCLUSIONS

Phonological awareness does predict reading performance in very preterm children. Rapid naming appears to be related to complex multiple academic delays, and may reflect a neurological timing or efficiency factor with effects independent of intelligence and significantly influenced by immaturity and illness.

White matter volume and anisotropy in preterm children: a pilot study of neurocognitive correlates

The objectives of this study were to evaluate the differences in whole brain white matter (WM) volume and anisotropy between preterm and term children and to determine the relationships with cognitive outcome. Twenty-five low birth weight (BW), preterm, neurologically normal children between 8.8 and 11.5 y of age were recruited for volumetric and diffusion-tensor magnetic resonance imaging (DTI), together with 13 age-matched term control subjects. Subsequent intelligence quotient (IQ) testing was performed for 21 preterm children within 6 mo of imaging studies. We computed the mean volume and fractional anisotropy (FA) of the whole brain WM and compared the differences between the two groups. Mean WM volume and FA were significantly lower in the preterm group (p = 0.014 and p < 0.001, respectively). Multiple regression analysis found both WM volume and FA to be independent variables significantly affecting full scale IQ (FSIQ) (r2 = 0.407, p = 0.021 and r2 = 0.496, p = 0.005, respectively) after adjusting for BW, gestational age (GA), and gender. In the evaluation of the whole brain WM of preterm children, we found that both volume and FA remain reduced at late childhood with both parameters significantly affecting long-term cognitive outcome.

Reports of birthweight by adolescents and their mothers: comparing accuracy and identifying correlates

Birthweight is associated with health outcomes throughout the lifespan. Official birthweight records are not always available, and researchers must rely on self-reports for birthweight information. This study evaluates the accuracy of adolescent self-reports of birthweight, using medical records as a standard, and compares it with maternal reports. It also examines potential correlates of accuracy. Respondents are 17-year-old adolescents and their mothers, who participated in a follow-up study of randomly selected samples from newborn discharge lists (1983-85) of two major hospitals in south-east Michigan. Nearly one-quarter of the adolescents stated that they did not know their own birthweight, with males twice as likely as females to respond 'don't know'. In addition, self-reports of birthweight among the remaining adolescents were inaccurate, and accuracy was inversely related to birthweight. While maternal reports of offspring's birthweight are highly accurate across diverse subgroups of the population, adolescent self-reports of birthweight are unlikely to be useful in medical research.

A Cumulative Risk Factor Model for Early Identification of Academic Difficulties in Premature and Low Birth Weight Infants

OBJECTIVES

Premature and low birth weight children have a high prevalence of academic difficulties. This study examines a model comprised of cumulative risk factors that allows early identification of these difficulties.

METHODS

This is a secondary analysis of data from a large cohort of premature (<37 weeks gestation) and LBW (<2500 g) children. The study subjects were 8 years of age and 494 had data available for reading achievement and 469 for mathematics. Potential predictor variables were categorized into 4 domains: sociodemographic, neonatal, maternal mental health and early childhood (ages 3 and 5). Regression analysis was used to create a model to predict reading and mathematics scores.

RESULTS

Variables from all domains were significant in the model, predicting low achievement scores in reading (R (2) of 0.49, model p-value < .0001) and mathematics (R (2) of 0.44, model p-value < .0001). Significant risk factors for lower reading scores, were: lower maternal education and income, and Black or Hispanic race (sociodemographic); lower birth weight and male gender (neonatal); lower maternal responsivity (maternal mental health); lower intelligence, visual-motor skill and higher behavioral disturbance scores (early childhood). Lower mathematics scores were predicted by lower maternal education, income and age and Black or Hispanic race (sociodemographic); lower birth weight and higher head circumference (neonatal); lower maternal responsivity (maternal mental health); lower intelligence, visual-motor skill and higher behavioral disturbance scores (early childhood).

CONCLUSIONS

Sequential early childhood risk factors in premature and LBW children lead to a cumulative risk for academic difficulties and can be used for early identification.

Association between intelligence quotient scores and extremely low birth weight in school-age children

BACKGROUND

Extremely low birth weight (ELBW) has been associated with poor cognitive development in children. We performed this research to establish the association between ELBW and the influence of biological and socioeconomic factors in the intelligence quotient (IQ) score in school-age children.

METHODS

This study comprised 184 children with mean and standard deviation of 6.9 +/- 0.8 years of age. The children were divided into four groups based on their birth weight as follows: group A (n = 25), < or =1000 g; group B (n = 52), 1001-1500 g; group C (n = 66), 1501-2500 g; and group D (n = 41), > or =2501 g. The Stanford-Binet after the Terman-Merril Intelligence Scale was used to determine IQ scores.

RESULTS

Mean and standard deviation (SD) of IQ values were 95.3 +/- 11.3 for group A, 103.1 +/- 14.4 for group B, 105.1 +/- 12.3 for group C, and 106.8 +/- 11.7 for group D (p = 0.003). Frequencies of children with scores below normal distribution were the following: 28% in group A; 10% in group B; 15% in group C, and 5% in group D (chi(2) = 0.04). Bronchopulmonary dysplasia and parental education were associated with lower IQ scores (p <0.05).

CONCLUSIONS

IQ scores of children born with ELBW were significantly lower when compared to children born with a higher birth weight. Additional studies are important to determine whether these neurodevelopmental delays persist into adulthood, and whether there are additional factors associated with catch-up and recovery.

The Maudsley Family Study: premorbid and current general intellectual function levels in familial bipolar I disorder and schizophrenia

The distinction of psychosis into schizophrenia and bipolar disorder has been increasingly challenged with some evidence suggesting that the two conditions may have common etiologic and pathogenic mechanisms. We compared the premorbid and current intellectual function of bipolar patients from multiply affected families, and those of their first-degree relatives, with those of a similar series of schizophrenic subjects, as well as their relatives, and normal controls. Only schizophrenic subjects showed lower premorbid IQ, suggesting that they, but not the bipolar patients or either relative group, had suffered neurodevelopmental impairment. However, both groups of patients had comparably poor current general intellectual levels, implying that some common pathogenic process operates once illness has begun. The two groups of relatives showed distinct differences in intellectual function but we cannot exclude the possibility that these were a function of our sampling methods.