Verbal short-term memory span in children: long-term modality dependent effects of intrauterine growth restriction

Foetal growth restriction has negative influence on narrative skills in 8-10-year-old children

AIM

The risk for neurocognitive difficulties is increased in children born with foetal growth restriction (FGR), but no data exist yet on their narrative skills. The narrative skills of 8- to 10-year-old children born with FGR between 24 and 40 weeks were compared with those of children born with appropriate growth for gestational age (AGA).

METHODS

A prospectively collected cohort of 36 children with FGR was recruited prenatally at a Finnish tertiary hospital from 1998-2001, and 31 children with AGA served as controls. Narrative skills were assessed using a standardised test, and correlations between narrative, communication, reading and spelling skills were studied.

RESULTS

Children born with FGR produced significantly less information and shorter utterances in their narratives than the AGA group. Children born preterm with FGR performed significantly more poorly in their narratives than the preterm AGA group. Poor narrative skills correlated with poor communication, reading and spelling skills.

CONCLUSION

Children born with FGR had poorer narrative skills compared with their AGA peers at the age of 8-10 years, and narrative skills were linked to other language-based skills, which underlines the importance of early detection and preventive measures to optimise the educational outcome of children born with FGR.

Fetal hemodynamics and language skills in primary school-aged children with fetal growth restriction: A longitudinal study

AIM

Long-term follow-up studies on children born with fetal growth restriction (FGR) have revealed a specific profile of neurocognitive difficulties, including problems with speech, language and literacy skills. We hypothesized that problems with communication skills, including language use and literacy skills of FGR children at primary school age are associated with prenatal circulatory changes.

METHODS

Ultrasonographic assessment of fetoplacental hemodynamics was performed prenatally in 77 fetuses. After a follow-up period of 8-10 years, assessment of reading and spelling skills using standardized tests and the Children's Communication Questionnaire (CCC-2) was performed to measure different language skills in 37 FGR children and 31 appropriately grown (AGA) controls, matched for gestational age.

RESULTS

Increased blood flow resistance in the umbilical artery (UA PI >2 SD) during fetal life showed odds ratios of 3.5-19.1 for poor literacy and communication skills and need for speech and language therapy. Furthermore, FGR children with prenatal cerebral vasodilatation (cerebroplacental ratio (CPR) < -2 SD) had significantly poorer literacy and communication skills, at primary school age compared to the AGA controls. Abnormal CPR demonstrated odds ratios of 4.2-28.1 for poor literacy and communication skills and need for speech and language therapy.

CONCLUSION

Increased blood flow resistance in the umbilical artery and cerebral vasodilatation are associated with poor communication, language, and literacy skills at early school age in children born with FGR. These findings indicate the need for continuous follow-up of this group and timely targeted support to ensure optimal academic outcomes.

School Age Neurological and Cognitive Outcomes of Fetal Growth Retardation or Small for Gestational Age Birth Weight

Children who were growth restricted in utero (FGR) and are born small for gestational age (SGA) may experience poorer long term neurological and cognitive outcomes. Those also born preterm may have particular difficulties. The objective of this paper was to review the literature on school age neurocognitive outcome for term and preterm children that was published in the last 15 years. Considering term born children first, there is evidence that these children are at higher risk for Cerebral Palsy (CP) than those born appropriate for gestational age (AGA); information on neuromotor function in the absence of CP is somewhat contradictory. With regards to cognitive outcome, the most common finding was that being born SGA and/or FGR at term does not impact negatively on general intellectual functioning, commonly assessed by IQ scores. There was some indication that they may experience particular problems with attention. With regards to children born preterm, the risk of CP appears not to be increased compared to those preterms born AGA. For preterm children who do not develop CP, motor outcome is more affected by post-natal and post-neonatal brain growth than intrauterine growth. In contrast to term born children, preterm SGA and/or FGR children are at increased risk of cognitive and behavioral difficulties, and in common with term born children, are at higher risk than their AGA counterparts of difficulties with attentional control. In conclusion, preterm born SGA and/or FGR children are at higher risk of neurodevelopmental problems in the school years. It is important to continue to follow up children into the school age years because these difficulties may take time to emerge, and may be more visible in the more demanding school environment.

Foetal growth restriction is associated with poor reading and spelling skills at eight years to 10 years of age

AIM

Foetal growth restriction (FGR) is associated with communication problems, which might lead to poor literacy skills. The reading and spelling skills of eight- to 10-year-old FGR children born at 24-40 gestational weeks were compared with those of their gestational age-matched, appropriately grown (AGA) peers.

METHODS

A prospectively collected cohort of 37 FGR and 31 AGA children was recruited prenatally at a Finnish tertiary care centre during 1998-2001. The children's reading and spelling skills were assessed using standardised tests for Finnish-speaking second and third graders.

RESULTS

Significantly more children performed below the 10th percentile normal values for reading and spelling skills in the FGR group than in the AGA group. At nine years of age, the FGR children had significantly poorer performance in word reading skills and reading fluency, reading accuracy and reading comprehension than the AGA controls. No between-group differences were detected at eight years of age.

CONCLUSION

FGR is associated with poor performance in reading and spelling skills. A third of the FGR children performed below the 10th percentile normal values at nine years of age. These results indicate a need to continuously evaluate linguistic and literacy skills as FGR children age to ensure optimal support.

Diffusion-weighted magnetic resonance imaging of the fetal brain in intrauterine growth restriction

OBJECTIVE

Diffusion-weighted magnetic resonance imaging (DWI) is a sensitive method for assessing brain maturation and detecting brain lesions, providing apparent diffusion coefficient (ADC) values as a measure of water diffusion. Abnormal ADC values are seen in ischemic brain lesions, such as those associated with acute or chronic hypoxia. The aim of this study was to assess whether ADC values in the fetal brain were different in fetuses with severe intrauterine growth restriction (IUGR) compared with normal controls.

METHODS

Brain magnetic resonance imaging (MRI) with single-shot axial DWI (b = 0 and b = 700 s/mm² ) was performed in 30 fetuses with severe IUGR (estimated fetal weight < 3^rd centile with absent or reversed umbilical artery Doppler flow) and in 24 normal controls of similar gestational age. Brain morphology and biometry were analyzed. ADC values were measured in frontal and occipital white matter, centrum semiovale, thalami, cerebellar hemisphere and pons. Frontal-occipital and frontal-cerebellar ADC ratios were calculated, and values were compared between IUGR fetuses and controls.

RESULTS

There was no difference in gestational age at MRI between IUGR and control fetuses (IUGR, 30.2 ± 1.6 weeks vs controls, 30.7 ± 1.4 weeks). Fetal brain morphology and signals were normal in all fetuses. Brain dimensions (supratentorial ± infratentorial) were decreased (Z-score, < -2) in 20 (66.7%) IUGR fetuses. Compared with controls, IUGR fetuses had significantly lower ADC values in frontal white matter (1.97 ± 0.23 vs 2.17 ± 0.22 × 10^-3 mm² /s; P < 0.0001), thalami (1.04 ± 0.15 vs 1.13 ± 0.10 ×10^-3 mm² /s; P = 0.0002), centrum semiovale (1.86 ± 0.22 vs 1.97 ± 0.23 ×10^-3 mm² /s; P = 0.01) and pons (0.85 ± 0.19 vs 0.94 ± 0.12 ×10^-3 mm² /s; P = 0.043). IUGR fetuses had a lower frontal-occipital ADC ratio than did normal fetuses (1.00 ± 0.11 vs 1.08 ± 0.05; P = 0.003).

CONCLUSIONS

ADC values in IUGR fetuses were significantly lower than in normal controls in the frontal white matter, thalami, centrum semiovale and pons, suggesting abnormal maturation in these regions. However, the prognostic value of these ADC changes is still unknown. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Cognitive and Behavioral Outcomes of Intrauterine Growth Restriction School-Age Children

CONTEXT

Children who experienced intrauterine growth restriction (IUGR) may be at increased risk for adverse neurologic developmental outcomes during the school-age years of life.

OBJECTIVE

To estimate the effect of IUGR on cognition and behavior in school-aged children.

DATA SOURCES

Medline, Embase, and PsycINFO were searched for English-language articles published after 1980.

DATA SELECTION

We included case-control studies reporting cognitive and/or behavioral data of children who had IUGR and were evaluated afterfifth birthday.

DATA EXTRACTION

Cognitive data from 15 studies and behavioral data from 6 studies were selected with a total of 1559 cases and 1630 controls. The cognitive scores and behavioral outcomes were extracted.

RESULTS

The controls had significantly higher cognitive scores than the children with IUGR (standardized mean difference [SMD] -0.38, 95% confidence interval [CI] -0.51 to -0.25, P < .00001). The IQ scores of the IUGR group were not significantly correlated with mean birth weight and gestational age (P > .05). Five trials were included in the behavioral outcomes trial, the behavior scores were significantly different between the groups with and without IUGR (SMD 0.31, 95% CI 0.13 to 0.48, P = .001). The incidence of attention-deficit/hyperactivity disorder (ADHD) was not significantly different between 2 groups (P = .11).

LIMITATIONS

The number of studies that assessed behavioral and ADHD outcome is small.

CONCLUSIONS

The findings demonstrate that IUGR is associated with lower cognitive scores in school-age children. However, further large-scale trials are needed to assess the effects of IUGR on the outcome of behavioral disorder and ADHD.

Neurodevelopment in children with intrauterine growth restriction: adverse effects and interventions

Intrauterine growth restriction (IUGR) is associated with higher rates of fetal, perinatal, and neonatal morbidity and mortality. The consequences of IUGR include short-term metabolic, hematological and thermal disturbances that lead to metabolic syndrome in children and adults. Additionally, IUGR severely affects short- and long-term fetal brain development and brain function (including motor, cognitive and executive function) and neurobehavior, especially neuropsychology. This review details the adverse effects of IUGR on fetal brain development and discusses intervention strategies.

Short and long term neuro-behavioral alterations in type 1 diabetes mellitus pediatric population

Type 1 diabetes mellitus (T1DM) is one of the most prevalent chronic conditions affecting individuals under the age of 18 years, with increasing incidence worldwide, especially among very young age groups, younger than 5. There is still no cure for the disease, and therapeutic goals and guidelines are a challenge. Currently, despite T1DM intensive management and technological interventions in therapy, the majority of pediatric patients do not achieve glycemic control goals. This leads to a potential prognosis of long term diabetic complications, nephrological, cardiac, ophthalmological and neurological. Unfortunately, the neurological manifestations, including neurocognitive and behavioral complications, may present soon after disease onset, during childhood and adolescence. These manifestations may be prominent, but at times subtle, thus they are often not reported by patients or physicians as related to the diabetes. Furthermore, the metabolic mechanism for such manifestations has been inconsistent and difficult to interpret in practical clinical care, as reported in several reviews on the topic of brain and T1DM. However, new technological methods for brain assessment, as well as the introduction of continuous glucose monitoring, provide new insights and information regarding brain related manifestations and glycemic variability and control parameters, which may impact the clinical care of children and youth with T1DM. This paper provides a comprehensive review of the most recently reported behavioral, cognitive domains, sleep related, electrophysiological, and structural alterations in children and adolescences from a novel point of view. The review focuses on reported impairments based on duration of T1DM, its timeline, and modifiable disease related risk parameters. These findings are not without controversy, and limitations of data are presented in addition to recommendations for future research direction.

Early childhood neurodevelopment after intrauterine growth restriction: a systematic review

BACKGROUND AND OBJECTIVE

Children who experienced intrauterine growth restriction (IUGR) may be at increased risk for adverse developmental outcomes in early childhood. The objective of this study was to carry out a systematic review of neurodevelopmental outcomes from 6 months to 3 years after IUGR.

METHODS

PubMed, Embase, PsycINFO, Maternity and Infant Care, and CINAHL databases were searched by using the search terms intrauterine, fetal, growth restriction, child development, neurodevelopment, early childhood, cognitive, motor, speech, language. Studies were eligible for inclusion if participants met specified criteria for growth restriction, follow-up was conducted within 6 months to 3 years, methods were adequately described, non-IUGR comparison groups were included, and full English text of the article was available. A specifically designed data extraction form was used. The methodological quality of included studies was assessed using well-documented quality-appraisal guidelines.

RESULTS

Of 731 studies reviewed, 16 were included. Poorer neurodevelopmental outcomes after IUGR were described in 11. Ten found motor, 8 cognitive, and 7 language delays. Other delays included social development, attention, and adaptive behavior. Only 8 included abnormal Doppler parameters in their definitions of IUGR.

CONCLUSIONS

Evidence suggests that children are at risk for poorer neurodevelopmental outcomes following IUGR from 6 months to 3 years of age. The heterogeneity of primary outcomes, assessment measures, adjustment for confounding variables, and definitions of IUGR limits synthesis and interpretation. Sample sizes in most studies were small, and some examined preterm IUGR children without including term IUGR or AGA comparison groups, limiting the value of extant studies.

Neuropsychological deficits in young adults born small-for-gestational age (SGA) at term

Reduced IQ, learning difficulties and poor school performance have been reported in small-for-gestational-age (SGA) subjects. However, few studies include a comprehensive neuropsychological assessment. Our aim was to study neuropsychological functioning in young adults born SGA at term. A comprehensive neuropsychological test battery was administered to 58 SGA subjects (birth weight <10th centile) born at term, and 81 term non-SGA controls (birth weight ≥10th centile). The SGA group obtained significantly (p < .01) lower scores on the attention, executive and memory domains compared to non-SGA controls and showed higher risk of obtaining scores below -1.5 SD on the memory domain (odds ratio = 13.3, 95% confidence interval: 1.57, 112.47). At a subtest level, the SGA group obtained lower scores on most neuropsychological tests, with significant differences on 6 of 46 measures: the Trail Making Test 3 (letter sequencing), the Wechsler Memory Scale mental control and the auditory immediate memory scale, the Design Fluency, the Stroop 3 (inhibition) and the Visual Motor Integration (VMI) motor coordination subtest. Young adults born SGA score more poorly on neuropsychological tests compared with non-SGA controls. Differences were modest, with more significant differences in the memory domain.

Metabolomics reveals metabolic alterations by intrauterine growth restriction in the fetal rabbit brain

Background

Intrauterine Growth Restriction (IUGR) due to placental insufficiency occurs in 5–10% of pregnancies and is a major risk factor for abnormal neurodevelopment. The perinatal diagnosis of IUGR related abnormal neurodevelopment represents a major challenge in fetal medicine. The development of clinical biomarkers is considered a promising approach, but requires the identification of biochemical/molecular alterations by IUGR in the fetal brain. This targeted metabolomics study in a rabbit IUGR model aimed to obtain mechanistic insight into the effects of IUGR on the fetal brain and identify metabolite candidates for biomarker development.

Methodology/Principal Findings

At gestation day 25, IUGR was induced in two New Zealand rabbits by 40–50% uteroplacental vessel ligation in one horn and the contralateral horn was used as control. At day 30, fetuses were delivered by Cesarian section, weighed and brains collected for metabolomics analysis. Results showed that IUGR fetuses had a significantly lower birth and brain weight compared to controls. Metabolomics analysis using liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) and database matching identified 78 metabolites. Comparison of metabolite intensities using a t-test demonstrated that 18 metabolites were significantly different between control and IUGR brain tissue, including neurotransmitters/peptides, amino acids, fatty acids, energy metabolism intermediates and oxidative stress metabolites. Principle component and hierarchical cluster analysis showed cluster formations that clearly separated control from IUGR brain tissue samples, revealing the potential to develop predictive biomarkers. Moreover birth weight and metabolite intensity correlations indicated that the extent of alterations was dependent on the severity of IUGR.

Conclusions

IUGR leads to metabolic alterations in the fetal rabbit brain, involving neuronal viability, energy metabolism, amino acid levels, fatty acid profiles and oxidative stress mechanisms. Overall findings identified aspargine, ornithine, N-acetylaspartylglutamic acid, N-acetylaspartate and palmitoleic acid as potential metabolite candidates to develop clinical biomarkers for the perinatal diagnosis of IUGR related abnormal neurodevelopment.

Neurodevelopmental delay in small babies at term: a systematic review

OBJECTIVE

Being small for gestational age (SGA) or having fetal growth restriction (FGR) may be associated with poorer neurodevelopmental outcomes compared to being appropriate for gestational age (AGA). The aim of this paper was to evaluate the existence and magnitude of decrease in neurodevelopmental scores in SGA and FGR infants born at term from a systematic review of the existing literature.

METHODS

Studies of neurodevelopment in SGA/FGR babies were identified from a search of the internet scientific databases. Studies that included preterm births and those that did not define absolute indices of standardized cognitive outcome were excluded. SGA was defined as birth weight below the 10(th) centile for gestation and FGR as the same birth-weight standard with abnormal umbilical artery Doppler ultrasound or evidence of abnormal placentation on pathology specimen studies. Effect size was calculated as the standardized mean difference between neurodevelopment scores of controls and SGA/FGR children.

RESULTS

There were 28 studies of SGA, with a total of 7861 SGA and 91 619 control AGA babies, and three studies of FGR, with a total of 119 FGR and 49 control AGA babies. Data synthesis showed that standardized neurodevelopmental scores in SGA babies were 0.32 SD (95% CI, 0.25-0.38) below those for normal controls, though with heterogeneity between studies (I(2) = 68.3%). Insufficient data were available for FGR babies.

CONCLUSION

The findings of the study demonstrate that among babies born at term, being SGA is associated with lower scores on neurodevelopmental outcomes compared to AGA controls. A trial designed to evaluate the effects of intervention in small fetuses born at term in order to improve the neurodevelopmental outcome is urgently needed.

Severe small size for gestational age and cognitive function: catch-up phenomenon possible

OBJECTIVE

We sought to compare cognitive functioning in children born with birthweight <3% vs ≥3% for gestational age (GA) between 9 months and kindergarten.

STUDY DESIGN

Nonanomalous singletons from the Early Childhood Longitudinal Study-Birth Cohort were included. Associations between weight for GA and cognitive functioning were examined using a series of confounder-adjusted general linear models.

RESULTS

Of 3633 cohorts, 585 (16%) were <3% for GA. At 9 months, cognitive performance of newborns <3% was about 12 percentile points lower than their normal counterparts (P < .001). By 2 years, however, no significant cognitive differences between these groups were observed (P = .668). Academic performance at preschool age (around 3.5 years) was not different for reading (P = .245) or math (P = .880), nor different at kindergarten age.

CONCLUSION

Newborns <3% for GA exhibit catch-up cognitive functioning by 2 years, with relatively no decrements in academic functioning observed by kindergarten.

Intrauterine growth and neuropsychological performance in very low birth weight preschoolers

In this study we examined the association between intrauterine growth, indexed either as a categorical variable or continuous dimension, and neuropsychological outcome, in a very low birth weight (VLBW) sample of 143 preschoolers. When the commonly used split at the 10th percentile rank was applied to classify intrauterine growth restriction (IUGR), we found that the growth restricted group (n = 25) exhibited significantly poorer performance in the global motor domain, but not on any other neuropsychological measure. In contrast, when adequacy of intrauterine growth was indexed by standardized birth weight, a continuous dimension, this early risk factor explained a unique portion of the variance in global cognitive abilities and visuospatial skills, as well as in global, fine, and gross motor skills. These findings are consistent with recent magnetic resonance imaging data disclosing global neurodevelopmental changes in the brains of preterm infants with IUGR. When cases classified with IUGR (<10th percentile) were excluded, the relationship between adequacy of intrauterine growth and global cognitive abilities remained significant despite range restriction. Hence, an association between appropriateness of intrauterine growth and global intellectual outcome may be observed even within the population of VLBW preschoolers with adequate standardized birth weight.

Intrauterine growth-restricted neonates born at term or preterm: how different?

Late onset intrauterine growth restriction is a common form of growth restriction, mainly caused by placenta-vascular insufficiency. Whether the intrauterine or extrauterine environment offers a better long-term outcome for the growth-restricted fetus remains unclear. We compared the risk factors and long-term outcomes of late onset growth-restricted neonates delivered between 31-36 weeks of gestation vs those delivered at term. This prospective cohort study included 114 preterm and 193 term born growth-restricted neonates. They underwent a neurobehavioral examination (neonatal period), a neurodevelopmental assessment and the Bayley Scales of Infant Development (age 2 years), and neuromotor assessment and the Wechsler Preschool and Primary Scale of Intelligence (age 6 years). Growth-restricted neonates born prematurely exhibited a significantly higher incidence of maternal hypertension, a maternal history of abortions and stillbirths, increased intrapartum and postnatal complication rates, and abnormal neonatal neurobehavioral scores than expected. Both preterm and term born growth-restricted groups, however, exhibited comparable long-term neurodevelopmental and cognitive outcomes at ages 2 and 6 years. Although prematurely born neonates undergo an earlier growth restriction process and exhibit a higher perinatal risk factor profile, their long-term outcomes are comparable to those of growth-restricted neonates born at term.

Auditory and cognitive abilities of children suspected of auditory processing disorder (APD)

OBJECTIVE

Auditory processing disorder (APD) is typically characterised by difficulties in 'listening', particularly to speech in a noisy environment, despite normal peripheral function. In school-age children, APD has attracted considerable interest because of suspicions that it may lead to learning difficulties, especially affecting language and literacy. Here, we evaluated auditory and cognitive abilities in a group of children referred for an auditory evaluation on the grounds of a suspected auditory processing disorder (susAPD), and in age-matched children who were typically developing, in order to determine the extent to which any deficits in cognitive abilities could be related to auditory deficits.

METHODS

A battery of auditory and cognitive tests was applied to 20 susAPD school-age children, all reported as having listening/hearing problems but performing within normal limits for standard audiometric assessments. Also tested was a group of 28 age-matched controls. The auditory tasks consisted of two simple same/different discrimination tasks, one using speech, and one nonspeech. The cognitive evaluation comprised a vocabulary test, a test of grammar and four non-verbal IQ measures. Symptoms of Attention Deficit Hyperactivity Disorder (ADHD) were assessed in the susAPD group through a standardised questionnaire.

RESULTS

A significant proportion of susAPD children appeared to display genuine auditory deficits evidenced by poor performance on at least one of the auditory tasks, although about 1/3 had no detectable deficit. Children in the susAPD group scored consistently lower than the controls on cognitive measures that were both verbal (vocabulary and grammar) and non-verbal. Strikingly, susAPD children with relatively good auditory performance did not differ in cognitive ability from susAPD children with poor auditory performance. Similarly, within-group correlations between auditory and cognitive measures were weak or non-existent. Measures of ADHD did not correlate with any aspect of auditory or cognitive performance.

CONCLUSIONS

Although children suspected of having APD do show, on average, poorer performance on a number of auditory tasks, the presence or absence of an auditory deficit appears to have little impact on the development of the verbal and non-verbal skills tested here.