Neurodevelopmental outcome in preterm infants

Increased PLAGL1 Gene Methylation in Cord Blood is Positively Correlated with Brain Injury in Chorioamniotic Preterm Infants

The study aims to explore the epigenetic mechanisms of neurodevelopmental impairment accompanied in chorioamniotic preterm infants. Our study included 16 full-term infants and 69 preterm infants. The methylation status of the pleomorphic adenoma gene-like 1 (PLAGL1) gene in the cord blood was determined by pyrosequencing. Brain B-ultrasonography and magnetic resonance imaging (MRI) were performed to diagnose brain injury. The activity of candidate fragments of PLAGL1 and the effect of methylation on PLAGL1 activity were evaluated by double luciferase reporter assay. The data showed that there were no differences in the methylation levels of each Cytosine-phosphate-Guanine (CpG) site of PLAGL1 between full-term and preterm infants. Within preterm infants, the methylation levels of the CpG2, CpG3, CpG4, and CpG5 sites were increased in the chorioamnionitis group compared with the no chorioamnionitis group. The areas under curves (AUCs) of the receiver operating characteristic (ROC) curves of CpG2, CpG3, CpG4, and CpG5 were 0.656, 0.653, 0.670, and 0.712, respectively. Meanwhile, the methylation level of the CpG2 site was increased in preterm babies with brain injury compared with those without brain injury, and the AUC of CpG2 was 0.648, with a sensitivity of 75.9% and a specificity of 50.0%. A double luciferase reporter assay revealed that PLAGL1 fragments had enhancer-like activity and that the methylated form of PLAGL1 weakened this activity. Thus, PLAGL1 hypermethylation in chorioamniotic preterm infants is positively correlated with brain injury. Our results suggest a potential use for PLAGL1 methylation as a biomarker in the diagnosis of brain injury.

Sensory processing and sleep characteristics in preterm infants in the early period of life

OBJECTIVE

The present study aimed to investigate the following: (i) differences in sensory processing and sleep characteristics between preterm infants born at < 32 weeks', vs. those born at ≥ 32 weeks' gestation; (ii) differences in sleep characteristics between preterm infants with typical vs. atypical sensory processing; and (iii) relationship between sensory processing and sleep characteristics in preterm infants at 3 months of age.

METHODS

A total of 189 preterm infants, 54 born at < 32 weeks' gestation (26 females; mean gestational age [standard deviation (SD)], 30.1 [1.7] weeks), and 135 born at ≥ 32 weeks' gestation (78 females; mean gestational age [SD], 34.9 [0.9] weeks) were included in the present study. Sleep characteristics were evaluated using the Brief Infant Sleep Questionnaire, and sensory processing was assessed using the Infant Sensory Profile-2.

RESULTS

There were no significant differences in sensory processing (P > 0.05) or sleep characteristics (P > 0.05) between the preterm groups; however, more infants snored in the <32 weeks' gestation group (P = 0.035). Preterm infants with atypical sensory processing showed lower nighttime (P = 0.027) and total sleep durations (P = 0.032), and higher rates of nocturnal wakefulness (P = 0.038) and snoring (P = 0.001) than preterm infants with typical sensory processing. A significant relationship, therefore, was observed between sensory processing and sleep characteristics (P < 0.05).

CONCLUSIONS

Sensory processing patterns may play an important role in understanding sleep problems in preterm infants. The early detection of sleep problems and sensory processing difficulties are necessary for early intervention.

Differential Placental DNA Methylation of NR3C1 in Extremely Preterm Infants With Poorer Neurological Functioning

BACKGROUND

Understanding underlying mechanisms of neurodevelopmental impairment following preterm birth may enhance opportunities for targeted interventions. We aimed to assess whether placental DNA methylation of selected genes affected early neurological functioning in preterm infants.

METHODS

We included 43 infants, with gestational age <30 weeks and/or birth weight <1,000 g and placental samples at birth. We selected genes based on their associations with several prenatal conditions that may be related to poor neurodevelopmental outcomes. We determined DNA methylation using pyrosequencing, and neurological functioning at 3 months post-term using Prechtl's General Movement Assessment, including the Motor Optimality Score-Revised (MOS-R).

RESULTS

Twenty-four infants had atypical MOS-R, 19 infants had near-optimal MOS-R. We identified differences in average methylation of NR3C1 (encoding for the glucocorticoid receptor) [3.3% (95%-CI: 2.4%-3.9%) for near-optimal vs. 2.3% (95%-CI: 1.7%-3.0%), p = 0.008 for atypical], and at three of the five individual CpG-sites. For EPO, SLC6A3, TLR4, VEGFA, LEP and HSD11B2 we found no differences between the groups.

CONCLUSION

Hypomethylation of NR3C1 in placental tissue is associated with poorer neurological functioning at 3 months post-term in extremely preterm infants. Alleviating stress during pregnancy and its impact on preterm infants and their neurodevelopmental outcomes should be further investigated.

Cerebral Oxygenation in Preterm Infants With Necrotizing Enterocolitis

BACKGROUND AND OBJECTIVES

Preterm infants with necrotizing enterocolitis (NEC) are known to have worse neurodevelopmental outcomes, but there is no substantial evidence to support an underlying pathophysiology. We aimed to examine whether cerebral oxygenation differs in those infants who develop NEC compared to cerebral oxygenation in those who do not.

METHODS

We examined 48 infants <30 weeks' gestation admitted to a tertiary level NICU from October 2016 to May 2018. Infants with birth weight less than or equal to the second percentile, abnormal antenatal dopplers or twin-to-twin-transfusion-syndrome were excluded. Cerebral oximetry measurements were performed by using a near-infrared spectroscopy (NIRS) monitor weekly for 60 minutes, allowing measurement of cerebral tissue oxygenation index from the first week of life to 36 weeks postconceptional age. Weekly clinical status was also recorded. NEC was defined as greater than or equal to Bell stage 2.

RESULTS

The median birth weight was 884 g (range of 460-1600 g), the median weeks' gestational age was 26 + 3/7 (23 + 0/7 to 29 + 6/7), and 52% were girls. In total, 276 NIRS measurements were completed, and 7 infants developed NEC. NIRS measurements from 1 infant with NEC and 4 infants without NEC who developed hemorrhagic parenchymal infarcts were excluded from analysis. Infants who developed NEC had significantly lower cerebral tissue oxygenation index than those who did not (P = .011), even when adjusted for confounders, including gestational age, birth weight, patent ductus arteriosus, enteral feeds, sex, ethnicity, and hemoglobin.

CONCLUSIONS

Infants with NEC have significantly lower cerebral tissue oxygenation throughout their neonatal intensive care stay in comparison with those who did not develop NEC. This is a novel finding and could explain their worse neurodevelopmental outcome.

The impact of choice of norms on classification of motor impairment for children born very preterm

BACKGROUND

The Movement Assessment Battery for Children-Second Edition (Movement ABC-2) is widely used to assess children's motor function, yet there is a lack of normative data for many countries.

AIMS

To assess the extent to which the application of different population reference norms for the Movement ABC-2 affects the classification and prevalence of motor impairment.

DESIGN

Data were obtained from two Portuguese regions participating in the Screening to Improve Health in Very Preterm Infants in Europe (SHIPS) Study, which was a five year follow-up of a cohort of children born at <32 weeks' gestation in 2011-2012 in 19 regions in 11 European countries. Perinatal data were extracted from medical records and the Movement ABC-2 was administered at five years of age.

SUBJECTS

Of 542 Portuguese children eligible for the five-year follow-up, 413 (76.2%) were evaluated.

OUTCOME MEASURES

Movement ABC-2 raw scores were converted to standardized scores using norms from four countries with national standardisations (UK, Netherlands/Belgium, France and Italy).

RESULTS

The prevalence of significant movement difficulties (total score ≤ 5th percentile) was 28.5% using Dutch/Flemish norms, 23.3% using French norms, 16.5% using UK norms and 11.4% using Italian norms; 10.8% and 68.3% of the children were consistently classified as having significant movement difficulties and as not having significant movement difficulties, respectively, according to any norms. However, for 20.9% of children there was a disagreement in motor function status using different norms.

CONCLUSION

The use of different test norms has a large impact on the proportion of children classified with significant movement difficulties, with implications for clinical referrals, healthcare costs and research. Our results underscore the importance of using appropriately validated tests with sound psychometric properties, and raise questions about the large differences in norms for the Movement ABC-2 in European countries.

Long-term outcomes of survivors of neonatal insults: A systematic review and meta-analysis

BACKGROUND

The Millennium Developmental Goals ensured a significant reduction in childhood mortality. However, this reduction simultaneously raised concerns about the long-term outcomes of survivors of early childhood insults. This systematic review focuses on the long-term neurocognitive and mental health outcomes of neonatal insults (NNI) survivors who are six years or older.

METHODS

Two independent reviewers conducted a comprehensive search for empirical literature by combining index and free terms from the inception of the databases until 10th October 2019. We also searched for additional relevant literature from grey literature and using reference tracking. Studies were included if they: were empirical studies conducted in humans; the study participants were followed at six years of age or longer; have an explicit diagnosis of NNI, and explicitly define the outcome and impairment. Medians and interquartile range (IQR) of the proportions of survivors of the different NNI with any impairment were calculated. A random-effect model was used to explore the estimates accounted for by each impairment domain.

RESULTS

Fifty-two studies with 94,978 participants who survived NNI were included in this systematic review. The overall prevalence of impairment in the survivors of NNI was 10.0% (95% CI 9.8-10.2). The highest prevalence of impairment was accounted for by congenital rubella (38.8%: 95% CI 18.8-60.9), congenital cytomegalovirus (23.6%: 95% CI 9.5-41.5), and hypoxic-ischemic encephalopathy (23.3%: 95% CI 14.7-33.1) while neonatal jaundice has the lowest proportion (8.6%: 95% CI 2.7-17.3). The most affected domain was the neurodevelopmental domain (16.6%: 95% CI 13.6-19.8). The frequency of impairment was highest for neurodevelopmental impairment [22.0% (IQR = 9.2-24.8)] and least for school problems [0.0% (IQR = 0.0-0.00)] in any of the conditions.

CONCLUSION

The long-term impact of NNI is also experienced in survivors of NNI who are 6 years or older, with impairments mostly experienced in the neurodevelopmental domain. However, there are limited studies on long-term outcomes of NNI in sub-Saharan Africa despite the high burden of NNI in the region.

TRIAL REGISTRATION

Registration number: CRD42018082119.

Risk factors for executive function difficulties in preschool and early school-age preterm children

AIM

To investigate the relationship between executive functioning and social and perinatal risk factors in four- to five-year-old preterm children.

METHODS

Using standardised measures of general intelligence and performance-based executive function (EF) tests prior to starting kindergarten, 141 children born preterm (<33 weeks of gestation) and 77 term comparison children were assessed. Parental and teacher reports of executive functioning were completed when the children commenced kindergarten. The preterm and the term comparison groups were compared on measures of intelligence and EFs using independent-groups t-tests, and multivariate regression analyses were performed to identify factors predictive of intelligence and executive functioning in the preterm group.

RESULTS

The preterm group performed significantly more poorly than the comparison group on all intelligence and EF tests. The parental reports of the preterm and term comparison children's EF did not differ significantly, but the teachers reported elevated EF difficulties for the preterm group. Higher social risk, in particular lower educational level of the main caregiver, was the strongest predictor for the preterm children's intelligence and EF results.

CONCLUSION

Social risk factors are strongly associated with impaired early EF outcomes in preterm children.

A longitudinal ICF-CY-based evaluation of functioning and disability of children born with very low birth weight

This paper aims to describe the longitudinal changes in disability, defined by the International Classification of Functioning, Disability, and Health - Children and Youth version (ICF-CY) biopsychosocial model, and developmental outcomes in a cohort of 56 very low birth weight children over 14-20 months. We used a neurofunctional assessment, the Griffiths Mental Development Scales-Revised: 2-8 years (Griffiths 2-8) to evaluate psychomotor development and the ICF-CY questionnaire for ages 0-3 and 3-6 to address children's disability. Extension indexes on the basis of ICF-CY categories were computed, and longitudinal change was tested. Complete follow-up was available for 55 children (mean age 36.7 months, SD 6.7). Considering the sample as a whole, neurofunctional assessment, Griffiths score and disability were basically stable. When the subsample of children with the higher baseline functioning was taken into account, some degree of worsening, in terms of an increase in the number of impairments and limitations, was found. Our results show that disability profiles, neurofunctional assessment and global development were basically stable, except for the subgroup of children who were in the intermediate/high-functioning cluster at baseline. The increased disability among these children might be because of the possibility to observe a wider set of age-specific problems, such as emotional, regulation and social abilities that are not detectable at an early stage of development and that might lead to reduced participation in social activities.

Altered resting-state functional connectivity in emotion-processing brain regions in adults who were born very preterm

BACKGROUND

Very preterm birth (VPT; <32 weeks of gestation) has been associated with impairments in emotion regulation, social competence and communicative skills. However, the neuroanatomical mechanisms underlying such impairments have not been systematically studied. Here we investigated the functional integrity of the amygdala connectivity network in relation to the ability to recognize emotions from facial expressions in VPT adults.

METHOD

Thirty-six VPT-born adults and 38 age-matched controls were scanned at rest in a 3-T MRI scanner. Resting-state functional connectivity (rs-fc) was assessed with SPM8. A seed-based analysis focusing on three amygdalar subregions (centro-medial/latero-basal/superficial) was performed. Participants' ability to recognize emotions was assessed using dynamic stimuli of human faces expressing six emotions at different intensities with the Emotion Recognition Task (ERT).

RESULTS

VPT individuals compared to controls showed reduced rs-fc between the superficial subregion of the left amygdala, and the right posterior cingulate cortex (p = 0.017) and the left precuneus (p = 0.002). The VPT group further showed elevated rs-fc between the left superficial amygdala and the superior temporal sulcus (p = 0.008). Performance on the ERT showed that the VPT group was less able than controls to recognize anger at low levels of intensity. Anger scores were significantly associated with rs-fc between the superficial amygdala and the posterior cingulate cortex in controls but not in VPT individuals.

CONCLUSIONS

These findings suggest that alterations in rs-fc between the amygdala, parietal and temporal cortices could represent the mechanism linking VPT birth and deficits in emotion processing.

The Emergence of Tool Use in Preterm Infants

Preterm born children without neurological impairments have been shown to present some visual-manual coordination deficits, more or less depending on their tonicity and the degree of prematurity. In this paper, we compare the development of tool use in 15-23-month-old preterm infants born after 33-36 weeks of gestation without neurological complications with that of full-term infants according to corrected age. Understanding the affordance of a tool is an important cognitive milestone in early sensorimotor period. Using a tool to bring within reach an out-of-reach object, for instance, has been shown to develop during the 2nd year in full-term infants. Here we presented preterm infants with an attractive toy out of reach and with a rake-like tool within reach in five conditions of spatial relationships between the toy and the tool. Like full-terms, preterm infants used the tool with success in conditions of spatial contiguity around 15-17 months. In conditions of a spatial gap between tool and toy, i.e., the only conditions which shows without ambiguity that the infant understands the affordance of the tool, preterm infants as a group showed no delay for tool use: the frequency of spontaneous successes started to increase after 18 months, and demonstration became effective after that age. However, further analyses showed that only the preterm infants without hypotonia and born after 36 weeks of pregnancy developed tool use without delay. Hypotonic preterm infants were still largely unsuccessful in the conditions of spatial gap, even at the end of the study. The degree of prematurity also influenced the performance at tool use. These results, following the observation of a delay in the development of bimanual coordination and of handedness in the same infants at 10-12 months in a previous study, show that low risk preterm infants can still be impaired for the development of new manual skills beyond the 1st year. Thus, hypotonic preterm infants and infants born before 36 weeks of pregnancy should be followed and might benefit from early intervention programs.

Assessment of general movements and heart rate variability in prediction of neurodevelopmental outcome in preterm infants

BACKGROUND

Adverse neurologic outcome in preterm infants could be associated with abnormal heart rate (HR) characteristics as well as with abnormal general movements (GMs) in the 1st month of life.

AIMS

To demonstrate to what extent GMs assessment can predict neurological outcome in preterm infants in our clinical setting; and to assess the clinical usefulness of time-domain indices of heart rate variability (HRV) in improving predictive value of poor repertoire (PR) GMs in writhing period.

STUDY DESIGN

Qualitative assessment of GMs at 1 and 3 months corrected age; 24h electrocardiography (ECG) recordings and analyzing HRV at 1 month corrected age.

SUBJECTS

Seventy nine premature infants at risk of neurodevelopmental impairments were included prospectively.

OUTCOME MEASURES

Neurodevelopmental outcome was assessed at the age of 2 years corrected. Children were classified as having normal neurodevelopmental status, minor neurologic dysfunction (MND), or cerebral palsy (CP).

RESULTS

We found that GMs in writhing period (1 month corrected age) predicted CP at 2 years with sensitivity of 100%, and specificity of 72.1%. Our results demonstrated the excellent predictive value of cramped synchronized (CS) GMs, but not of PR pattern. Analyzing separately a group of infants with PR GMs we found significantly lower values of HRV parameters in infants who later developed CP or MND vs. infants with PR GMs who had normal outcome.

CONCLUSIONS

The quality of GMs was predictive for neurodevelopmental outcome at 2 years. Prediction of PR GMs was significantly enhanced with analyzing HRV parameters.

Fidgety movements - tiny in appearance, but huge in impact

OBJECTIVES

To describe fidgety movements (FMs), i.e., the spontaneous movement pattern that typically occurs at 3-5 months after term age, and discuss its clinical relevance.

SOURCES

A comprehensive literature search was performed using the following databases: MEDLINE/PubMed, CINAHL, The Cochrane Library, Science Direct, PsycINFO, and EMBASE. The search strategy included the MeSH terms and search strings ('fidgety movement*') OR [('general movement*') AND ('three month*') OR ('3 month*')], as well as studies published on the General Movements Trust website (www.general-movements-trust.info).

SUMMARY OF THE DATA

Virtually all infants develop normally if FMs are present and normal, even if their brain ultrasound findings and/or clinical histories indicate a disposition to later neurological deficits. Conversely, almost all infants who never develop FMs have a high risk for neurological deficits such as cerebral palsy, and for genetic disorders with a late onset. If FMs are normal but concurrent postural patterns are not age-adequate or the overall movement character is monotonous, cognitive and/or language skills at school age will be suboptimal. Abnormal FMs are unspecific and have a low predictive power, but occur exceedingly in infants later diagnosed with autism.

CONCLUSIONS

Abnormal, absent, or sporadic FMs indicate an increased risk for later neurological dysfunction, whereas normal FMs are highly predictive of normal development, especially if they co-occur with other smooth and fluent movements. Early recognition of neurological signs facilitates early intervention. It is important to re-assure parents of infants with clinical risk factors that the neurological outcome will be adequate if FMs develop normally.

The General Movement Assessment Helps Us to Identify Preterm Infants at Risk for Cognitive Dysfunction

Apart from motor and behavioral dysfunctions, deficits in cognitive skills are among the well-documented sequelae of preterm birth. However, early identification of infants at risk for poor cognition is still a challenge, as no clear association between pathological findings based on neuroimaging scans and cognitive functions have been detected as yet. The Prechtl General Movement Assessment (GMA) has shown its merits for the evaluation of the integrity of the young nervous system. It is a reliable tool for identifying infants at risk for neuromotor deficits. Recent studies on preterm infants demonstrate that abnormal general movements (GMs) also reflect impairments of brain areas involved in cognitive development. The aim of this systematic review was to discuss studies that included (i) the Prechtl GMA applied in preterm infants, and (ii) cognitive outcome measures in six data bases. Seven studies met the inclusion criteria and yielded the following results: (a) children born preterm with consistently abnormal GMs up to 8 weeks after term had lower intelligence quotients at school age than children with an early normalization of GMs; (b) from 3 to 5 months after term, several qualitative, and quantitative aspects of the concurrent motor repertoire, including postural patterns, were predictive of intelligence at 7–10 years of age. These findings in 428 individuals born preterm suggest that normal GMs along with a normal motor repertoire during the first months after term are markers for normal cognitive development until at least age 10.

Motor performance, postural stability and behaviour of non-disabled extremely preterm or extremely low birth weight children at four to five years of age

BACKGROUND

Extremely preterm or extremely low birth weight (ELBW) children who are non-disabled and otherwise healthy are at risk of neurodevelopmental impairments. Further understanding of these impairments is needed before commencement of formal education to optimise participation levels at a critical time point for these children.

AIMS

To explore motor co-ordination, postural stability, limb strength and behaviour of non-disabled four to five year old children with a history of extreme prematurity or ELBW.

STUDY DESIGN

Prospective-descriptive-cohort-study.

SUBJECTS

50 children born at less than 28 weeks gestation or who had a birth weight less than 1000g with minimal/mild motor impairments and no significant neurological/cognitive impairments.

OUTCOME MEASURES

Movement Assessment Battery for Children second-edition (MABC-2), single leg stance test (SLS), lateral reach test, standing long jump test and Child Behaviour Checklist for preschool children (CBCL).

RESULTS

The mean percentile rank of the extremely preterm or ELBW sample on MABC-2 was 31% (SD 23%). SLS right (mean ± SD; 4.6 ± 2.5s) and lateral reach to the right (10.0 ± 3.9 cm) were slightly stronger than SLS left (4.4 ± 3.3s) and lateral reach left (9.9 ± 3.5 cm). The average for standing long jump was 71.6 cm (SD 21.0 cm). All participants were classified as 'normal' on CBCL syndrome scale scores, internalizing and externalizing syndrome T scores and total problem T score.

CONCLUSIONS

This sample of non-disabled extremely preterm or ELBW children performed in the lower range of normal. These children continue to be at risk of impairments, therefore, ongoing monitoring and tailored intervention may optimise development.

Cerebral oxygenation is associated with neurodevelopmental outcome of preterm children at age 2 to 3 years

AIM

The aim of the study was to determine whether regional cerebral tissue oxygen saturation (r(c)SO2) and fractional tissue oxygen extraction (FTOE), using near-infrared spectroscopy, are associated with neurodevelopmental outcome of preterm infants.

METHOD

We measured rc SO2 on days 1, 2, 3, 4, 5, 8, and 15 after birth in 83 preterm infants (<32wks gestational age), and calculated FTOE=(SpO2 -r(c)SO2)/SpO2. Cognitive, motor, neurological, and behavioural outcomes were determined at 2 to 3 years using the Bayley Scales of Infant and Toddler Development, Third Edition (BSID-III), an age-specific neurological examination, and the Child Behavior Checklist (CBCL) respectively. Multiple linear regression analyses were used to determine whether r(c)SO2 and FTOE contributed to outcome.

RESULTS

We followed up 67 infants. The lower quartile (P(25-50)) and highest quartile (P(75-100)) of r(c)SO2 on day 1 were associated with poorer cognitive outcome (p=0.044 and p=0.008 respectively). A lower area under the curve (AUC; over 15d) of r(c)SO2 was associated with poorer cognitive outcome (p=0.014). The lower quartile (P(25-50)) AUC of r(c)SO2 was associated with poorer fine motor outcome (p=0.004). The amount of time r(c)SO2 <50% on day 1 was negatively associated with gross motor outcome (p=0.002). The highest quartile of FTOE on day 1 was associated with poorer total motor outcome (p=0.041).

INTERPRETATION

Cerebral oxygen saturation during the first 2 weeks after birth is associated with neurodevelopmental outcome of preterm infants at 2 to 3 years. High and low r(c)SO2 on day 1 were associated with poorer neurodevelopmental outcome.

Cortical structural abnormalities in very preterm children at 7 years of age

We analyzed long-lasting alterations in brain morphometry associated with preterm birth using volumetric and surface-based analyses applied to children at age 7 years. Comparison of 24 children born very preterm (VPT) to 24 healthy term-born children revealed reductions in total cortical gray matter volume, white matter volume, cortical surface area and gyrification index. Regional cortical shape abnormalities in VPT children included the following: shallower anterior superior temporal sulci, smaller relative surface area in the inferior sensori-motor cortex and posterior superior temporal cortex, larger relative surface area and a cingulate sulcus that was shorter or more interrupted in medial frontoparietal cortex. These findings indicate a complex pattern of regional vulnerabilities in brain development that may contribute to the diverse and long-lasting neurobehavioral consequences that can occur after very premature birth.

Functional outcome at school age of preterm-born children treated with high-dose dexamethasone

BACKGROUND

Postnatal dexamethasone (DXM) treatment is associated with adverse motor outcome. It is largely unknown as to what extent functional outcome at school age is affected.

AIMS

Our first aim was to determine motor, cognitive, and behavioural outcome at school age of preterm-born children treated with high-dose DXM for pulmonary problems. Our second aim was to identify DXM-related risk factors for adverse outcome.

STUDY DESIGN

In this cohort study, we included 53 very preterm-born children treated with DXM (starting dose 0.5mg/kg/d) after the first week of life. At the median age of 9 years, we performed a detailed neuropsychological assessment.

RESULTS

Compared to the norm population, DXM-treated children scored worse on the Movement-ABC (abnormal fine motor, ball skills and balance: 59%, 47% and 30%, respectively). They more often had total (36%), verbal (32%) and performance IQs (55%) below 85 (P<.001, P=.002, P<.001, respectively). On each of the remaining measures, DXM-treated children scored worse than the norm population, except for verbal long-term memory and verbal recognition memory. DXM-related risk factors were associated with poorer performance.

CONCLUSIONS

At school age, multiple domains of functional outcome were affected in DXM-treated children. Risk factors related to the use of DXM should be considered as serious potentiaters of adverse outcome in children treated with high-dose DXM.

Spatial working memory deficits in male rats following neonatal hypoxic ischemic brain injury can be attenuated by task modifications

Hypoxia-ischemia (HI; reduction in blood/oxygen supply) is common in infants with serious birth complications, such as prolonged labor and cord prolapse, as well as in infants born prematurely (<37 weeks gestational age; GA). Most often, HI can lead to brain injury in the form of cortical and subcortical damage, as well as later cognitive/behavioral deficits. A common domain of impairment is working memory, which can be associated with heightened incidence of developmental disorders. To further characterize these clinical issues, the current investigation describes data from a rodent model of HI induced on postnatal (P)7, an age comparable to a term (GA 36–38) human. Specifically, we sought to assess working memory using an eight-arm radial water maze paradigm. Study 1 used a modified version of the paradigm, which requires a step-wise change in spatial memory via progressively more difficult tasks, as well as multiple daily trials for extra learning opportunity. Results were surprising and revealed a small HI deficit only for the final and most difficult condition, when a delay before test trial was introduced. Study 2 again used the modified radial arm maze, but presented the most difficult condition from the start, and only one daily test trial. Here, results were expected and revealed a robust and consistent HI deficit across all weeks. Combined results indicate that male HI rats can learn a difficult spatial working memory task if it is presented in a graded multi-trial format, but performance is poor and does not appear to remediate if the task is presented with high initial memory demand. Male HI rats in both studies displayed impulsive characteristics throughout testing evidenced as reduced choice latencies despite more errors. This aspect of behavioral results is consistent with impulsiveness as a core symptom of ADHD—a diagnosis common in children with HI insult. Overall findings suggest that task specific behavioral modifications are crucial to accommodating memory deficits in children suffering from cognitive impairments following neonatal HI.

Difficulty in Mental, Neuromusculoskeletal, and Movement-Related School Functions Associated With Low Birthweight or Preterm Birth: A Meta-Analysis

OBJECTIVE. Our objective was to perform a meta-analysis to investigate whether low birthweight (LBW) or preterm birth was associated with difficulty in mental, neuromusculoskeletal, and movement-related school function tasks.

METHOD. Two search strategies produced 40 studies that met the inclusion criteria for the meta-analysis and yielded 549 effect sizes (d). Heterogeneity was evaluated by obtaining Q and I-squared values. Egger’s regression intercept test and a funnel plot were used to check for publication bias.

RESULTS. Children born LBW exhibited considerable difficulties in mental (d = −0.655, p &lt; .0001) and neuromusculoskeletal and movement-related tasks (d = −0.391, p &lt; .0001) compared with children of normal birthweight. Children born preterm also exhibited significant difficulties compared with full-term children in mental, neuromusculoskeletal, and movement-related tasks (d = −0.237, p &lt; .0001).

CONCLUSION. Deficits in mental and motor functions in children born LBW or preterm appear to have significant effects on school readiness and academic achievement.

Traumatic perforation of the lamina cribrosa during nasal intubation of a preterm infant

Traumatic perforation of the lamina cribrosa and penetration of the brain occurred during nasotracheal intubation of a preterm infant requiring resuscitation. This rare complication is specifically associated with the nasal route of intubation. The complication resulted in significant morbidity. The infant developed an extensive intracranial hemorrhage and posthemorrhagic hydrocephalus that required ventricular drainage. We recommend that nasotracheal intubation be performed with utmost care. We confirm Cameron and Lupton's recommendation of using a small feeding tube over which to slide the endotracheal tube. Despite extensive iatrogenic damage, the patient's neurodevelopmental follow-up at 2 years 9 months appeared relatively mild.

Development of fine motor skills in preterm infants

Fine motor skills are related to functioning in daily life and at school. We reviewed the status of knowledge, in preterm children, on the development of fine motor skills, the relation with gross motor skills, and risk factors for impaired fine motor skills. We searched the past 15 years in PubMed, using ['motor skills' or 'fine motor function' and 'preterm infant'] as the search string. Impaired gross and fine motor skills are among the most frequently occurring problems encountered by preterm children who do not develop cerebral palsy. The prevalence is around 40% for mild to moderate impairment and 20% for moderate impairment. Fine motor skill scores on the Movement Assessment Battery for Children are about 0.62 of a standard deviation lower compared with term children. Risk factors for fine motor impairments include moderately preterm birth (odds ratio [OR] 2.0) and, among very preterm children (<32 wk gestation), intra-uterine growth restriction (ORs 2-3), inflammatory conditions (late-onset sepsis and necrotizing enterocolitis, ORs 3-5), and dexamethasone therapy for bronchopulmonary dysplasia (OR 2.7). A better understanding of factors that play a role in the development of and recovery from brain injury could guide future intervention attempts aimed at improving fine motor skills of preterm children.

Cartography and connectomes

The past 25 years have seen great progress in parcellating the cerebral cortex into a mosaic of many distinct areas in mice, monkeys, and humans. Quantitative studies of interareal connectivity have revealed unexpectedly many pathways and a wide range of connection strengths in mouse and macaque cortex. In humans, advances in analyzing "structural" and "functional" connectivity using powerful but indirect noninvasive neuroimaging methods are yielding intriguing insights about brain circuits, their variability across individuals, and their relationship to behavior.

Which high-risk infants should we follow-up and how should we do it?

Early detection of neurodevelopmental delay and appropriate intervention has been associated with improved academic and social outcomes. Identifying those who are at high risk and might benefit is not straightforward. Approximately 2% of infants are admitted to a neonatal intensive care unit after birth and these babies are known to be at high risk of developmental impairment. While it is well recognised that the extreme preterm infant is at high risk of developmental impairment, there is increasing evidence of a risk in late preterm infants as well as those undergoing major cardiac and non-cardiac surgery. Not all infants are enrolled in multidisciplinary follow-up clinics with easy access to early intervention. These clinics are expensive to run with both limited and conflicting data on their long-term value. This review will concentrate on identifying which infants are at risk, reviewing the aetiology of the risk factors and the efficacy of follow-up clinics.