Parental bilingualism is associated with slower cognitive development in very low birth weight infants

Utilizing maternal prenatal cognition as a predictor of newborn brain measures of intellectual development

Identifying reliable indicators of cognitive functioning prior to age five has been challenging. Prior studies have shown that maternal cognition, as indexed by intellectual quotient (IQ) and years of education, predict child intelligence at school age. We examined whether maternal full scale IQ, education, and inhibitory control (index of executive function) are associated with newborn brain measures and toddler language outcomes to assess potential indicators of early cognition. We hypothesized that maternal indices of cognition would be associated with brain areas implicated in intelligence in school-age children and adults in the newborn period. Thirty-seven pregnant women and their newborns underwent an MRI scan. T2-weighted images and surface-based morphometric analysis were used to compute local brain volumes in newborn infants. Maternal cognition indices were associated with local brain volumes for infants in the anterior and posterior cingulate, occipital lobe, and pre/postcentral gyrus - regions associated with IQ, executive function, or sensori-motor functions in children and adults. Maternal education and executive function, but not maternal intelligence, were associated with toddler language scores at 12 and 24 months. Newborn brain volumes did not predict language scores. Overall, the pre/postcentral gyrus and occipital lobe may be unique indicators of early intellectual development in the newborn period. Given that maternal executive function as measured by inhibitory control has robust associations with the newborn brain and is objective, brief, and easy to administer, it may be a useful predictor of early developmental and cognitive capacity for young children.

Long-term effects of prenatal magnesium sulfate exposure on nervous system development in preterm-born children

This study used structural magnetic resonance imaging to analyze changes in the gray matter volume (GMV) of preterm-born (PTB) and term-born (TB) children to help elucidate the influence of magnesium sulfate treatment on the nervous system development. A total of 51 subjects were recruited, including 28 PTB and 23 TB children. The intelligence scale and MRI scan were completed at the corrected age of 10 to 16 years. A whole-brain voxel-wise analysis tested the main effect of the status (PTB without magnesium, PTB with magnesium, and TB) using a factorial design in SPM8. The mean volumes of the regions that showed significant group effects on the GMV after the FDR correction were extracted in the common space for each subject. Verbal and full-scale intelligence quotient scores were significantly lower for PTB children without magnesium than for TB children; however, the scores of PTB children with magnesium and TB children were almost identical. Compared with TB children, PTB children had significantly reduced left straight gyrus and left inferior frontal gyrus GMVs; however, the volumes of PTB children with magnesium were closer to those of TB children. Changes in the GMV of the left inferior frontal gyrus were significantly correlated with full-scale and verbal intelligence quotient scores, whereas the lower gestational age at the time of mgsou4 treatment led to a larger GMV of the left inferior frontal gyrus. Brain structural abnormalities could exist in PTB children. The GMVs of the left straight gyrus and left inferior frontal gyrus were significantly reduced in these children. The influence of magnesium sulfate treatment was not significant, but the cognitive levels of these children were significantly increased and almost identical to those of TB children. Initiation of magnesium sulfate treatment during gestation is negatively correlated with the left inferior frontal gyrus GMV.

Developmental trajectories of infants born at less than 30 weeks' gestation on the Bayley-III Scales

OBJECTIVE

To describe the cognitive, language and motor developmental trajectories of children born very preterm and to identify perinatal factors that predict the trajectories.

DESIGN

Data from a cohort of 1142 infants born at <30 weeks' gestation who were prospectively assessed on the Bayley Scales of Infant and Toddler Development, third edition (Bayley-III) at 3, 6, 12 and 24 months corrected age, were analysed using the Super Imposition by Translation and Rotation (SITAR) growth curve analysis model.

MAIN OUTCOME MEASURES

Developmental trajectory SITAR models for Bayley-III cognitive, language (receptive and expressive communication subscales) and motor (fine and gross motor subscales) scores.

RESULTS

The successfully fitted SITAR models explained 62% of variance in cognitive development, 68% in receptive communication, 53% in fine motor and 68% in the gross motor development. There was too much variation in the expressive communication subscale to fit a SITAR model. The rate of development (gradient of the curve) best explains the variation in trajectories of development in all domains. Lower gestational age, lower birth weight and male sex significantly predicted a slower rate of development.

CONCLUSION

The rate of development, rather than single time point developmental assessment, best predicts the very preterm infant's developmental trajectory and should be the focus for monitoring and early intervention.

Developing routinely recorded clinical data from electronic patient records as a national resource to improve neonatal health care: the Medicines for Neonates research programme

Background

Clinical data offer the potential to advance patient care. Neonatal specialised care is a high-cost NHS service received by approximately 80,000 newborn infants each year.

Objectives

(1) To develop the use of routinely recorded operational clinical data from electronic patient records (EPRs), secure national coverage, evaluate and improve the quality of clinical data, and develop their use as a national resource to improve neonatal health care and outcomes. To test the hypotheses that (2) clinical and research data are of comparable quality, (3) routine NHS clinical assessment at the age of 2 years reliably identifies children with neurodevelopmental impairment and (4) trial-based economic evaluations of neonatal interventions can be reliably conducted using clinical data. (5) To test methods to link NHS data sets and (6) to evaluate parent views of personal data in research.

Design

Six inter-related workstreams; quarterly extractions of predefined data from neonatal EPRs; and approvals from the National Research Ethics Service, Health Research Authority Confidentiality Advisory Group, Caldicott Guardians and lead neonatal clinicians of participating NHS trusts.

Setting

NHS neonatal units.

Participants

Neonatal clinical teams; parents of babies admitted to NHS neonatal units.

Interventions

In workstream 3, we employed the Bayley-III scales to evaluate neurodevelopmental status and the Quantitative Checklist of Autism in Toddlers (Q-CHAT) to evaluate social communication skills. In workstream 6, we recruited parents with previous experience of a child in neonatal care to assist in the design of a questionnaire directed at the parents of infants admitted to neonatal units.

Data sources

Data were extracted from the EPR of admissions to NHS neonatal units.

Main outcome measures

We created a National Neonatal Research Database (NNRD) containing a defined extract from real-time, point-of-care, clinician-entered EPRs from all NHS neonatal units in England, Wales and Scotland (n = 200), established a UK Neonatal Collaborative of all NHS trusts providing neonatal specialised care, and created a new NHS information standard: the Neonatal Data Set (ISB 1595) (see http://webarchive.nationalarchives.gov.uk/±/http://www.isb.nhs.uk/documents/isb-1595/amd-32–2012/index_html; accessed 25 June 2018).

Results

We found low discordance between clinical (NNRD) and research data for most important infant and maternal characteristics, and higher prevalence of clinical outcomes. Compared with research assessments, NHS clinical assessment at the age of 2 years has lower sensitivity but higher specificity for identifying children with neurodevelopmental impairment. Completeness and quality are higher for clinical than for administrative NHS data; linkage is feasible and substantially enhances data quality and scope. The majority of hospital resource inputs for economic evaluations of neonatal interventions can be extracted reliably from the NNRD. In general, there is strong parent support for sharing routine clinical data for research purposes.

Limitations

We were only able to include data from all English neonatal units from 2012 onwards and conduct only limited cross validation of NNRD data directly against data in paper case notes. We were unable to conduct qualitative analyses of parent perspectives. We were also only able to assess the utility of trial-based economic evaluations of neonatal interventions using a single trial. We suggest that results should be validated against other trials.

Conclusions

We show that it is possible to obtain research-standard data from neonatal EPRs, and achieve complete population coverage, but we highlight the importance of implementing systematic examination of NHS data quality and completeness and testing methods to improve these measures. Currently available EPR data do not enable ascertainment of neurodevelopmental outcomes reliably in very preterm infants. Measures to maintain high quality and completeness of clinical and administrative data are important health service goals. As parent support for sharing clinical data for research is underpinned by strong altruistic motivation, improving wider public understanding of benefits may enhance informed decision-making.

Future work

We aim to implement a new paradigm for newborn health care in which continuous incremental improvement is achieved efficiently and cost-effectively by close integration of evidence generation with clinical care through the use of high-quality EPR data. In future work, we aim to automate completeness and quality checks and make recording processes more ‘user friendly’ and constructed in ways that minimise the likelihood of missing or erroneous entries. The development of criteria that provide assurance that data conform to prespecified completeness and quality criteria would be an important development. The benefits of EPR data might be extended by testing their use in large pragmatic clinical trials. It would also be of value to develop methods to quality assure EPR data including involving parents, and link the NNRD to other health, social care and educational data sets to facilitate the acquisition of lifelong outcomes across multiple domains.

Study registration

This study is registered as PROSPERO CRD42015017439 (workstream 1) and PROSPERO CRD42012002168 (workstream 3).

Funding

The National Institute for Health Research Programme Grants for Applied Research programme (£1,641,471). Unrestricted donations were supplied by Abbott Laboratories (Maidenhead, UK: £35,000), Nutricia Research Foundation (Schiphol, the Netherlands: £15,000), GE Healthcare (Amersham, UK: £1000). A grant to support the use of routinely collected, standardised, electronic clinical data for audit, management and multidisciplinary feedback in neonatal medicine was received from the Department of Health and Social Care (£135,494).

Multilingualism was associated with lower cognitive outcomes in children who were born very and extremely preterm

Aim

This study determined whether cognitive outcomes differed between very preterm (VPT) and extremely preterm (EPT) children who were monolingual or multilingual when they reached the corrected ages of two and five years.

Methods

The data were collected at the Emma Children's Hospital, Amsterdam, The Netherlands, as part of our national neonatal follow‐up programme and comprised 325 VPT/EPT children born between January 1, 2007 and January 1, 2012. The study used the Third Editions of the Bayley Scales of Infant and Toddler Development and the Wechsler Preschool and Primary Scale of Intelligence.

Results

We compared 234 monolingual children, 65 multilingual children who spoke Dutch and at least one foreign language at home and 26 multilingual children who didn't speak Dutch at home. The best performers on the cognitive scale at two years of age and the verbal subscales at five years of age were the monolingual children, followed by the children who spoke Dutch and at least one foreign language at home, then the children who only spoke foreign languages at home.

Conclusion

In our study cohort from The Netherlands, multilingualism lowered the cognitive and verbal outcomes of VPT/EPT children at the corrected ages of two and five years.

The Effect of Bilingual Exposure on Executive Function Skills in Preterm and Full-Term Preschoolers

OBJECTIVE

To evaluate the effects of bilingual exposure on executive function (EF) skills, measured by parent-rating and performance-based instruments, in preterm and full-term preschoolers.

METHOD

Children age 3 to 5 years (mean 4.4) born preterm (PT; n = 82) and full term (FT; n = 79) had monolingual (PT-M, n = 51; FT-M, n = 53) or bilingual (PT-B, n = 31; FT-B, n = 26) language exposure. Groups were similar in age, gender and race, but PT children had lower socioeconomic status (SES) than FT children. Parents completed a language questionnaire and diary and a standardized parent rating of EF skills. Children completed EF tasks that tap response inhibition, working memory, and cognitive flexibility. ANCOVA and logistic regression examined effects on EF of birth group (PT/FT), language status (M/B), and birth group by language status interaction, controlling for age and SES.

RESULTS

Compared to children born FT, children born PT had significantly higher parent-rated EF scores and poorer performance on all but one EF task, both indicating more EF problems. No main effects of language status and no birth group by language status interactions were significant.

CONCLUSION

PT status was clearly associated with poorer EF skills, similar to many other studies. In this sample, bilingual exposure conferred neither an advantage nor disadvantage in the FT and PT group. This information may prove useful in counseling families of both PT and FT children about the impact of bilingual exposure on their children's cognitive skills.

Migrationshintergrund als Risikofaktor für die Entwicklung Frühgeborener im Alter von zwei Jahren

Zusammenfassung. Im Rahmen der Aachener Frühgeborenennachsorge wurden N = 199 Frühgeborene (< 32 SSW und/oder < 1500 g) der Geburtsjahrgänge 2007 bis 2011 im Alter von korrigiert zwei Jahren entwicklungsneurologisch nachuntersucht und ihr MDI mit dem Bayley II ermittelt. Die Daten wurden retrospektiv analysiert, um herauszufinden, ob der Migrationshintergrund die kognitive Leistungsfähigkeit zum Untersuchungszeitpunkt beeinflusst. Es zeigten sich keine Unterschiede hinsichtlich des Geschlechts, medizinischer Komplikationen und der Inanspruchnahme von Therapie zwischen Kindern mit (42 %) und ohne (58 %) Migrationshintergrund. In Übereinstimmung mit der Literatur lag die gesamte Aachener Stichprobe mit einem mittleren MDI von 83,3 (SD 17,4) eine Standardabweichung unter dem Durchschnitt der Referenzpopulation. Kinder mit Migrationshintergrund lagen im kognitiven Outcome 10 Punkte unter Kindern ohne diesen, was entscheidend durch das Vorliegen familiärer Risikofaktoren bedingt wurde. Im regressionsanalytischen Modell hatten familiäre Risikofaktoren und das Geburtsgewicht den größten Einfluss auf den kognitiven Outcome; aber auch das Vorliegen eines Migrationshintergrundes leistete einen zusätzlichen Beitrag zur Vorhersage. Frühgeborene mit Migrationshintergrund sollten daher als besondere Risikogruppe erkannt werden, insbesondere wenn sie zusätzlich familiäre Risikofaktoren aufweisen, um sie frühzeitig differenzierter fördern zu können.

Extremely preterm birth affects boys more and socio-economic and neonatal variables pose sex-specific risks

AIM

The early identification of at-risk extremely preterm (EPT) children could improve long-term outcomes. This study sought to investigate sex differences in developmental outcomes and to identify sex-specific predictors at two and a half years of age.

METHODS

We assessed 217 boys and 181 girls born before 27-week gestation using the Bayley Scales of Infant and Toddler Development, third edition (Bayley-III), as a part of the Extremely Preterm Infants in Sweden Study. Sex-specific differences were calculated. Socio-economic, birth and neonatal factors were calculated separately for boys and girls using regression models.

RESULTS

Girls scored significantly higher than boys on all Bayley-III indices. In both sexes, brain injury, long-term ventilator treatment and foreign-born mothers predicted lower scores. Receiving breast milk by hospital discharge predicted higher scores. Severe retinopathy of prematurity was the strongest predictor of cognitive and language deficits in boys. High parental education predicted higher cognitive and language scores in girls, whereas severe bronchopulmonary dysplasia was the strongest predictor of motor deficits.

CONCLUSION

Extreme prematurity seems to affect boys more than girls. Socio-economic and neonatal factors confer similar risks or protections on both sexes, but some variables pose sex-specific risks. An awareness of risk factors may provide the basis for treatment and follow-up guidelines.

Bilingualism as a potential strategy to improve executive function in preterm infants: a review

Preterm birth is associated with long-term deficits in executive functioning and cognitive performance. Using the model of brain plasticity as a theoretical framework, it is possible that preterm infants' neurodevelopmental sequelae can be altered. Evidence suggests that bilingualism confers cognitive advantages on executive functioning, so it is possible that bilingualism may improve preterm infants' neurodevelopment. However, bilingualism has only been studied in term children. This review examined literature that compared the performance of preterm-born children to term children and bilingual children to monolingual children on executive function tasks. To address cognitive disparities in preterm-born children, studies investigating the effect of bilingualism on preterm infants' executive functioning is warranted.

Language, motor and cognitive development of extremely preterm children: modeling individual growth trajectories over the first three years of life

Survival rate of extremely low gestational age (ELGA) newborns has increased over 80% in the last 15 years, but its consequences on the short- and longer-term developmental competencies may be severe. The aim of this study was to describe growth trajectories of linguistic, motor and cognitive skills among ELGA children, compared to full-term (FT) peers, from the first to the third year of life, a crucial period for development. Growth curve analysis was used to examine individual and group differences in terms of initial status at 12 months and rate of growth through the second and the third year of life with five points of assessment. Twenty-eight monolingual Italian children, of whom 17 were ELGA (mean GA 25.7 weeks) and 11 were FT children, were assessed through the BSID-III at 12, 18, 24, 30 and 36 months for language skills and at 12, 24 and 30 months for motor and cognitive skills. ELGA children presented significantly lower scores than FT peers in language, motor and cognitive skills and they did not overcome their disadvantage by 3 years, even if their corrected age was taken into account. Concerning growth curves, in motor development a significant increasing divergence was found showing a Matthew effect with the preterm sample falling further behind the FT sample. In linguistic and cognitive development, instead, a stable gap between the two samples was found. In addition, great inter-individual differences in rate of change were observed for language development in both samples. Our findings highlight the theoretical and clinical relevance of analyzing, through growth curve analyses, the developmental trajectories of ELGA children in language skills taking into account their inter-individual variability also across motor and cognitive domains.

LEARNING OUTCOMES

After reading this article, the reader will interpret: (a) characteristics and growth trajectories of ELGA children from the first to the third year of life with respect to FT children in language, motor and cognitive development; (b) the method of growth curve analyses to describe group as well as inter-individual trajectories; (c) the rate of inter-individual variability in language as well as motor and cognitive skills, which gives useful indications for early interventions.

Impact of caste on the neurodevelopment of young children from birth to 36 months of age: a birth cohort study in Chitwan Valley, Nepal

Background

Caste, a proxy of socioeconomic position, can influence the neurodevelopment of children through several pathways, including exposure to toxic elements. Studies from developing countries where caste is represented by prevailing caste groups and people are highly exposed to toxic elements can provide useful insights into the mechanisms of neurodevelopmental inequities among children. This study aims to investigate the impact of caste on the neurodevelopment of children from birth to 36 months of age in Chitwan Valley, Nepal, where people are exposed to high levels of arsenic (As) and lead (Pb).

Methods

Participants (N = 94) were mother-infant pairs from the Chitwan district in Nepal. The neurodevelopment of the infants was assessed using the Brazelton Neonatal Behavioral Assessment Scale, Third Edition, (NBAS III) at birth and the Bayley Scales of Infant Development, Second Edition, (BSID II) at ages 6, 24, and 36 months. Caste was categorized based on surname, which, in Nepal generally refers to one of four caste groups. We also measured the concentrations of As and Pb in cord blood.

Results

Caste was positively associated with the state regulation cluster score of the NBAS III at birth after adjustment for covariates (p for trend < 0.01). Adding cord blood As levels attenuated the association (p for trend = 0.12). With regard to neurodevelopment at six months of age, the third-ranked caste group scored higher than the first-ranked caste group on the Mental Development Index (MDI) of the BSID II (coefficient = 3.7; 95% confidence interval (CI) = 1.3 to 6.0). This difference remained significant after adjustment for cord blood As levels and other covariates was made (coefficient = 3.9; 95% CI = 1.2 to 6.7). The remaining clusters of the NBAS III and BSID II at 6, 24, and 36 months were not significantly associated with caste group.

Conclusions

Caste was positively associated with the state regulation cluster score of NBAS III at birth. This association was partially mediated by cord blood As levels. However, the negative impact of caste on neurodevelopment disappeared as the children grew. Furthermore, an inverse association between caste and MDI at six months of age was observed. Additional studies are needed to elucidate the mechanism of how caste affects neurodevelopment.

Effect of primary language on developmental testing in children born extremely preterm

AIM

The aim of this study was to better understand the impact of non-English language spoken in the home on measures of cognition, language and behaviour in toddlers born extremely preterm.

METHODS

Eight hundred and fifty children born at <28 weeks of gestational ages were studied. 427 male and 423 female participants from three racial/ethnic groups (White, Black and Hispanic) were evaluated at 18-22 months adjusted for age using the Bayley Scales of Infant Development third edition and the Brief Infant Toddler Social Emotional Assessment (BITSEA). Children whose primary language was Spanish (n = 98) were compared with children whose primary language was English (n = 752), using multivariable regression adjusted for medical and psychosocial factors.

RESULTS

Cognitive scores were similar between groups; however, receptive, expressive and composite language scores were lower for children whose primary language was Spanish. These differences remained significant after adjustment for medical and socio-economic factors. Spanish-speaking children scored worse on the BITSEA competence and problem scores using univariate analysis, but not after adjustment for medical and socio-economic factors.

CONCLUSION

Our finding that preterm children whose primary language was Spanish had similar cognitive but lower language scores than those whose primary language was English suggests that using English language-based testing tools may introduce bias against non-English-speaking children born preterm.

Evaluating preterm infants with the Bayley-III: patterns and correlates of development

This study investigates the Third Edition of the Bayley Scales of Infant and Toddler Development (Bayley-III) and: (1) early patterns of neurodevelopmental performance among preterm infants 8-12 months of age; and (2) correlations between known risk factors and neurodevelopmental outcome of preterm infants in this cohort. Mean Language Index (LI; 91±15) and Motor Index (MI; 94±17) were significantly lower than the Cognitive Index (CI; 102±15, p<.01). For the majority (53%) of infants, language development was their weakest domain; for another 39%, motor skills were the weakest area of development. Almost one-quarter (22%) of this cohort had mildly delayed language and motor skills, while 7% had significantly delayed language and motor skills. Regression models revealed severely abnormal head ultrasound significantly predicted MI, LI, and CI. Oxygen dependence at discharge predicted CI, LI, and race/ethnicity predicted LI, MI. Results support the addition of the Language Index to the newly revised Bayley-III Scales. Prediction models of developmental performance confirm known neonatal risk factors and reveal sociodemographic risk factors that call for additional research.

Cognitive outcome at 2 years of age in Finnish infants with very low birth weight born between 2001 and 2006

AIM

To study cognitive outcome of premature, very low birth weight (VLBW) infants in relation to parental education and neonatal data.

METHODS

A regional cohort of 182 VLBW infants born between 2001 and 2006 was followed up. Brain ultrasounds (US) were examined serially until term age and brain magnetic resonance imaging at term age. Neurological status was examined systematically. Cognitive development was assessed using the Mental Developmental Index (MDI) of Bayley Scales at 2 years of corrected age. A total of 192 healthy full-term (FT) controls were assessed with the MDI at 2 years of age.

RESULTS

The mean MDI in VLBW infants was 101.7 (SD 15.4), which was lower compared with FT controls (109.8, SD 11.7, p < 0.001). In regression analysis of the demographic and medical data of VLBW infants, postnatal corticosteroids (p = 0.04), intestinal perforation (p = 0.03) and major brain pathology (p = 0.02) were negatively associated with the MDI. In VLBW infants, the prevalence of neurodevelopmental impairment was 9.9% (3.3% MDI below 70, 7.1% cerebral palsy, 2.2% hearing aid, no blind infants).

CONCLUSION

Cognitive development of VLBW infants seemed to have improved in comparison with earlier publications, but it differed from the FT controls. Neonatal factors affected cognitive development. Therefore, updated regional follow-up data are important for clinicians.