Electrophysiologic evidence of impaired cross-modal recognition memory in 8-month-old infants of diabetic mothers

Association of Gestational Diabetes Mellitus and Perinatal Maternal Depression with Early Childhood Behavioral Problems: An Environmental Influences on Child Health Outcomes (ECHO) Study

This study examined the association of gestational diabetes mellitus (GDM), prenatal, and postnatal maternal depressive symptoms with externalizing, internalizing, and autism spectrum problems on the Preschool Child Behavior Checklist in 2379 children aged 4.12 ± 0.60 (48% female; 47% White, 32% Black, 15% Mixed Race, 4% Asian, <2% American Indian/Alaskan Native, <2% Native Hawaiian; 23% Hispanic). Data were collected from the NIH Environmental influences on Child Health Outcomes (ECHO) Program from 2009-2021. GDM, prenatal, and postnatal maternal depressive symptoms were each associated with increased child externalizing and internalizing problems. GDM was associated with increased autism behaviors only among children exposed to perinatal maternal depressive symptoms above the median level. Stratified analyses revealed a relation between GDM and child outcomes in males only.

Hyperglycemia and prematurity: a narrative review

Hyperglycemia is commonly encountered in extremely preterm newborns and physiologically can be attributed to immaturity in several biochemical pathways related to glucose metabolism. Although hyperglycemia is associated with a variety of adverse outcomes frequently described in this population, evidence for causality is lacking. Variations in definitions and treatment approaches have further complicated the understanding and implications of hyperglycemia on the immediate and long-term effects in preterm newborns. In this review, we describe the relationship between hyperglycemia and organ development, outcomes, treatment options, and potential gaps in knowledge that need further research. IMPACT: Hyperglycemia is common and less well described than hypoglycemia in extremely preterm newborns. Hyperglycemia can be attributed to immaturity in several cellular pathways involved in glucose metabolism in this age group. Hyperglycemia has been shown to be associated with a variety of adverse outcomes frequently described in this population; however, evidence for causality is lacking. Variations in definitions and treatment approaches have complicated the understanding and the implications of hyperglycemia on the immediate and long-term effects outcomes. This review describes the relationship between hyperglycemia and organ development, outcomes, treatment options, and potential gaps in knowledge that need further research.

The impact of maternal diabetes on the future health and neurodevelopment of the offspring: a review of the evidence

Maternal health during gestational period is undoubtedly critical in shaping optimal fetal development and future health of the offspring. Gestational diabetes mellitus is a metabolic disorder occurring in pregnancy with an alarming increasing incidence worldwide during recent years. Over the years, there is a growing body of evidence that uncontrolled maternal hyperglycaemia during pregnancy can potentially have detrimental effect on the neurodevelopment of the offspring. Both human and animal data have linked maternal diabetes with motor and cognitive impairment, as well as autism spectrum disorders, attention deficit hyperactivity disorder, learning abilities and psychiatric disorders. This review presents the available data from current literature investigating the relationship between maternal diabetes and offspring neurodevelopmental impairment. Moreover, possible mechanisms accounting for the detrimental effects of maternal diabetes on fetal brain like fetal neuroinflammation, iron deficiency, epigenetic alterations, disordered lipid metabolism and structural brain abnormalities are also highlighted. On the basis of the evidence demonstrated in the literature, it is mandatory that hyperglycaemia during pregnancy will be optimally controlled and the impact of maternal diabetes on offspring neurodevelopment will be more thoroughly investigated.

Cerebral Effects of Neonatal Dysglycemia

This article summarizes the available evidence reporting the relationship between perinatal dysglycemia and long-term neurodevelopment. We review the physiology of perinatal glucose metabolism and discuss the controversies surrounding definitions of perinatal dysglycemia. We briefly review the epidemiology of hypoglycemia and hyperglycemia in fetal, preterm, and term infants. We discuss potential pathophysiologic mechanisms contributing to dysglycemia and its effect on neurodevelopment. We highlight current strategies to prevent and treat dysglycemia in the context of neurodevelopmental outcomes. Finally, we discuss areas of future research and the potential role of continuous glucose monitoring.

Delayed maturation of P2 flash visual evoked potential (VEP) latency in newborns of gestational diabetic mothers

BACKGROUND

The prevalence of gestational diabetes mellitus (GDM) has rapidly increased, yet few prior studies have investigated parameters of early brain development in infants born to gestational diabetic mothers. The present study assessed visual evoked potentials (VEPs) in healthy infants born to gestational diabetic mothers and matched controls.

METHODS

After exclusions, in this prospective study we examined VEPs in 73 neonates between 37 weeks and 41 weeks gestation at birth (n = 37 infants of gestational diabetic mothers). Stroboscopic flashes were presented through closed eyelids during passive electroencephalography (EEG) recording to derive VEP waveforms during natural sleep.

RESULTS

There was a statistically significant moderate correlation between gestational age at birth and P2 latency of the flash VEP where P2 latency significantly decreased with increasing gestational age (Pearson's R(73) = -0.32, p < .01). There was also a significant moderate correlation between postnatal age (hours of life) and P2 latency of the flash VEP where P2 latency significantly decreased with increasing postnatal age (Pearson's R(73) = -0.23, p < .05). When controlling for gestational age at birth, postnatal age, and sex, there was a significant effect of group (GDM-exposed vs. control) on P2 latency of the flash VEP (p < .05). Infants of gestational diabetic mothers had a significantly longer P2 latency (M: 215.29 ± SD: 2.58 ms) than controls (M: 206.41 ± SD: 2.62 ms).

CONCLUSION

Our findings suggest P2 flash VEP latency is a potential measure of cortical maturation and marker of immature development in infants of gestational diabetic mothers.

Neonatal amygdala microstructure mediates the relationship between gestational glycemia and offspring adiposity

INTRODUCTION

To determine if variations in the neonatal amygdala mediate the association between maternal antenatal glycemia and offspring adiposity in early childhood.

RESEARCH DESIGN AND METHODS

123 non-obese pregnant women with no pregnancy complications aside from gestational diabetes underwent a 75 g 2-hour oral glucose tolerance test at 26-28 weeks' gestation. Volume and fractional anisotropy (FA) of the neonatal amygdala (5-17 days old) were measured by MRI. The Body Mass Index (BMI) z-scores and sum of skinfold thickness (subscapular and triceps) of these children were tracked up to 60 months of age (18, 24, 36, 48, 54 and 60 months).

RESULTS

Maternal fasting glucose levels were positively associated with the offspring's sum of skinfold thickness at age 48 months (β=3.12, 95% CI 0.18 to 6.06 mm) and 60 months (β=4.14, 95% CI 0.46 to 7.82 mm) and BMI z-scores at 48 months (β=0.94, 95% CI 0.03 to 1.85), 54 months (β=0.74, 95% CI 0.12 to 1.36) and 60 months (β=0.74, 95% CI 0.08 to 1.39). Maternal fasting glucose was negatively associated with the offspring's FA of the right amygdala (β=-0.019, 95% CI -0.036 to -0.003). Right amygdala FA was negatively associated with the sum of skinfold thickness in the offspring at age 48 months (β=-56.95, 95% CI -98.43 to -15.47 mm), 54 months (β=-46.18, 95% CI -88.57 to -3.78 mm), and 60 months (β=-53.69, 95% CI -105.74 to -1.64 mm). The effect sizes mediated by right amygdala FA between fasting glucose and sum of skinfolds were estimated at β=5.14 (95% CI 0.74 to 9.53) mm (p=0.022), β=4.40 (95% CI 0.08 to 8.72) (p=0.049) mm and β=4.56 (95% CI -0.17 to 9.29) mm (p=0.059) at 48, 54 and 60 months, respectively.

CONCLUSIONS

In the offspring of non-obese mothers, gestational fasting glucose concentration is negatively associated with neonatal right amygdala FA and positively associated with childhood adiposity. Neonatal right amygdala FA may be a potential mediator between maternal glycemia and childhood adiposity.

Selective morphological and volumetric alterations in the hippocampus of children exposed in utero to gestational diabetes mellitus

Prior epidemiological studies have found that in utero exposure to gestational diabetes mellitus (GDM) is associated with increased risk for neurodevelopmental disorders. However, brain alterations associated with GDM are not known. The hippocampus is pivotal for cognition and emotional regulation. Therefore, we assessed relationships between in utero exposure to GDM and hippocampal morphology and subfield structure during childhood. One hundred seventeen children aged 7–11 years (57% girls, 57% exposed to GDM), born at Kaiser Permanente Southern California, participated in the BrainChild Study. Maternal GDM status was determined from electronic medical records. Children underwent brain magnetic resonance imaging. Freesurfer 6.0 was used to measure hippocampal and individual hippocampal subfield gray matter volume (mm³). Morphological analyses on the hippocampal surface were carried out using shape analysis. GDM‐exposed children exhibited reduced radial thickness in a small, spatially‐restricted portion of the left inferior body of the hippocampus that corresponds to the CA1 subfield. There was a significant interaction between GDM‐exposure and sex on the right hippocampal CA1 subfield. GDM‐exposed boys had reduced right CA1 volume compared to unexposed boys, but this association was no longer significant after controlling for age. No significant group differences were observed in girls. Our results suggest that GDM‐exposure impacts shape of the left hippocampal CA1 subfield in both boys and girls and may reduce volume of right hippocampal CA1 only in boys. These in‐depth findings illuminate the unique properties of the hippocampus impacted by prenatal GDM‐exposure and could have important implications for hippocampal‐related functions.

Diabetes during Pregnancy: A Maternal Disease Complicating the Course of Pregnancy with Long-Term Deleterious Effects on the Offspring. A Clinical Review

In spite of the huge progress in the treatment of diabetes mellitus, we are still in the situation that both pregestational (PGDM) and gestational diabetes (GDM) impose an additional risk to the embryo, fetus, and course of pregnancy. PGDM may increase the rate of congenital malformations, especially cardiac, nervous system, musculoskeletal system, and limbs. PGDM may interfere with fetal growth, often causing macrosomia, but in the presence of severe maternal complications, especially nephropathy, it may inhibit fetal growth. PGDM may also induce a variety of perinatal complications such as stillbirth and perinatal death, cardiomyopathy, respiratory morbidity, and perinatal asphyxia. GDM that generally develops in the second half of pregnancy induces similar but generally less severe complications. Their severity is higher with earlier onset of GDM and inversely correlated with the degree of glycemic control. Early initiation of GDM might even cause some increase in the rate of congenital malformations. Both PGDM and GDM may cause various motor and behavioral neurodevelopmental problems, including an increased incidence of attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD). Most complications are reduced in incidence and severity with the improvement in diabetic control. Mechanisms of diabetic-induced damage in pregnancy are related to maternal and fetal hyperglycemia, enhanced oxidative stress, epigenetic changes, and other, less defined, pathogenic mechanisms.

Do infants represent human actions cross-modally? An ERP visual-auditory priming study

Recent findings indicate that 7-months-old infants perceive and represent the sounds inherent to moving human bodies. However, it is not known whether infants integrate auditory and visual information in representations of specific human actions. To address this issue, we used ERPs to investigate infants' neural sensitivity to the correspondence between sounds and images of human actions. In a cross-modal priming paradigm, 7-months-olds were presented with the sounds generated by two types of human body movement, walking and handclapping, after watching the kinematics of those actions in either a congruent or incongruent manner. ERPs recorded from frontal, central and parietal electrodes in response to action sounds indicate that 7-months-old infants perceptually link the visual and auditory cues of human actions. However, at this age these percepts do not seem to be integrated in cognitive multimodal representations of human actions.

Maternal glucose tolerance in pregnancy and child cognitive and behavioural problems in early and mid-childhood

BACKGROUND

Maternal abnormal glucose tolerance during pregnancy may adversely affect offspring cognition and behaviour, but few prospective studies investigated this association at multiple points throughout childhood.

OBJECTIVES

We hypothesised that maternal abnormal glucose tolerance is associated with child cognitive and behavioural outcomes in early and mid-childhood.

METHODS

We examined the associations of maternal abnormal glucose tolerance at 26-28 weeks of pregnancy with offspring cognitive and behavioural scores in 1421 children in the Project Viva pre-birth cohort. In early (mean 3.3 years) and mid-childhood (mean 7.9 years), we measured child cognition using validated instruments, the Kaufman Brief Intelligence Test, Wide Range Assessment of Memory and Learning, and the Wide Range Assessment of Visual Motor Abilities (WRAVMA); we assessed parent- and teacher-rated behavioural outcomes with the Strengths and Difficulties Questionnaire and the Behavioural Rating Inventory of Executive Function. We used linear regression models adjusted for potential confounders (maternal race/ethnicity, pre-pregnancy BMI, intelligence, age, parity, smoking status, education, and household income at enrolment, in addition to child's sex and age at assessment).

RESULTS

Of 1421 mothers, 69 (4.9%) had gestational diabetes mellitus, 43 (3.0%) impaired glucose tolerance, 122 (8.6%) isolated hyperglycaemia, and 1187 (83.5%) normal glucose tolerance. Offspring born to women with gestational diabetes mellitus had lower total WRAVMA scores (-3.09 points; 95% CI -6.12, -0.05) in early childhood compared with offspring of women with normal glucose tolerance. None of the abnormal glucose tolerance categories during pregnancy were associated with any of the cognitive outcomes (verbal, non-verbal, and visual motor scores) or behavioural measures in mid-childhood.

CONCLUSIONS

Children born to mothers who had gestational diabetes mellitus had slightly lower scores on one cognitive test in early childhood. We found no evidence to support that maternal abnormal glucose tolerance was associated with cognitive or behavioural development in mid-childhood.

Attentional Measures of Memory in Typically Developing and Hypoxic-Ischemic Injured Infants

Hypoxic–ischemic injury (HII) at birth has been found to relate to differences in development, including decreased memory performance. The current study assessed recognition memory in 6- and 12-month-old HII infants and typically developing (TD) infants using two eye-tracking paradigms well suited to explore explicit memory processes early in life: visual paired comparison (VPC) and relational memory (RM). During the VPC, infants were familiarized to a face and then tested for their novelty preference immediately and after a two-minute delay. At 6 months, neither HII nor TD showed a VPC novelty preference at immediate delay, but at 12 months, both groups did; after the two-minute delay, no group showed a novelty preference. During RM, infants were presented with blocks containing a learning phase with three different scene–face pairs, and a test phase with one of the three scenes and all three faces appearing simultaneously. When there was no interference from other scene–face pairs between learning and test, 6-month-old TD showed evidence of an early novelty preference, but when there was interference, they revealed an early familiarity preference. For 12-month-old TD, some evidence for a novelty preference during RM was seen regardless of interference. Although HII and TD showed similar recognition memory on the VPC, when looking at RM, HII infants showed subtle differences in their attention to the familiar and novel faces as compared to their TD peers, suggesting that there might be subtle differences in the underlying memory processing mechanisms between HII and TD. More work is needed to understand how these attentional patterns might be predictive of later memory outcomes.

Impaired Cortical Cytoarchitecture and Reduced Excitability of Deep-Layer Neurons in the Offspring of Diabetic Rats

Maternal diabetes has been related to low verbal task scores, impaired fine and gross motor skills, and poor performance in graphic and visuospatial tasks during childhood. The primary motor cortex is important for controlling motor functions, and embryos exposed to high glucose show changes in cell proliferation, migration, and differentiation during corticogenesis. However, the existing studies do not discriminate between embryos with or without neural tube defects, making it difficult to conclude whether the reported changes are related to neural tube defects or other anomalies. Furthermore, postnatal effects on central nervous system cytoarchitecture and function have been scarcely addressed. Through molecular, biochemical, morphological, and electrophysiological approaches, we provide evidence of impaired primary motor cerebral cortex lamination and neuronal function in pups from diabetic rats, showing an altered distribution of SATB2, FOXP2, and TBR1, impaired cell migration and polarity, and decreased excitability of deep-layer cortical neurons, suggesting abnormalities in cortico-cortical and extra-cortical innervation. Furthermore, phase-plot analysis of action potentials suggests changes in the activity of potassium channels. These results indicate that high-glucose insult during development promotes complex changes in migration, neurogenesis, cell polarity establishment, and dendritic arborization, which in turn lead to reduced excitability of deep-layer cortical neurons.

Could the E/A ratio be included in the cardiological evaluation of the offspring of diabetic mothers? A case-control study in South Sardinia

INTRODUCTION

Diabetes mellitus (DM) is a chronic disease widespread in the world. Sardinia represents, together with Finland, the region with the highest incidence of type 1 DM (DM1), as well as a high prevalence of gestational DM (GDM). Despite the improvement in obstetric surveillance, perinatal and long-term adverse outcomes are still frequent in the offspring of diabetic mothers. During gestations complicated by DM, fetal heart is one of the most affected organ potentially undergoing structural heart defects or several degrees of fetal myocardium hypertrophy and impaired cardiac function.

AIM

The aim of our study was to evaluate, through echocardiographic examination, cardiac features and performance in a South Sardinian population of newborns of diabetic mothers comparing them to a group of control subjects.

CONCLUSIONS

In our sample, the E/A ratio resulted a significant marker of early diastolic dysfunction in asymptomatic neonates born by diabetic mothers, even if such result should be confirmed on larger samples.

Vitamin B-12 Supplementation during Pregnancy and Early Lactation Does Not Affect Neurophysiologic Outcomes in Children Aged 6 Years

BACKGROUND

Deficiency of vitamin B-12 is common in pregnant Indian women. Assessment of neurophysiological measures using event-related potentials (ERPs) may yield additional information on the effects of maternal B-12 supplementation on child brain function.

OBJECTIVES

The objective of the study was to evaluate the effects of vitamin B-12 supplementation (50 μg daily orally) during pregnancy on the childhood ERP measures of positive waveform ∼300 ms after stimulus (P300) and mismatch negativity.

METHODS

This study was a follow-up of children born to pregnant women who received oral vitamin B-12 supplements (n = 62) compared with children of pregnant women who received placebo (n = 70) from a randomized controlled trial. The mean ± SD child age was 72 ± 1 mo. We used the Enobio system to assess the ERP measures P300 and mismatch negativity.

RESULTS

There were no significant differences in the primary outcomes, amplitudes, and latencies of the P300 results and the mismatch negativity between children in the supplementation and placebo groups. We combined the intervention and placebo groups for secondary analyses. On multiple variable regression analysis after adjusting for treatment group, intrauterine growth restriction, and home environment, P300 amplitude in children was significantly higher in the lowest tertile of third-trimester maternal methylmalonic acid (MMA) concentrations (β = 3034.04; 95% CI: 923.24, 5144.83) compared with the highest MMA tertile (β = 1612.12; 95% CI: -258.86, 3483.10, P = 0.005).

CONCLUSIONS

While no significant effects of maternal vitamin B-12 supplementation on children's ERP measures were seen at 72 mo, elevated maternal MMA concentrations in the third trimester were negatively associated with P300 amplitude in children. It may be worthwhile to study the impact of maternal and infant vitamin B-12 supplementation on childhood brain structure and function in longer and larger trials. The parent trial was registered at clinicaltrials.gov as NCT00641862.

Systemic endocrinopathies (thyroid conditions and diabetes): impact on postnatal life of the offspring

Fetal programming may influence childhood and adult life, determining the risk of specific diseases. During earlier stages of pregnancy, the transfer of maternal thyroid hormones to the fetus is vital for adequate neurologic development. The presence of severe maternal thyroid dysfunction, particularly severe iodine deficiency, is devastating, leading to irreversible neurologic sequelae. Moreover, mild maternal thyroid conditions, such as a mild-to-moderate iodine deficiency, may also lead to milder neurologic and behavioral conditions later during the life of the offspring. Maternal dysglycemia due to pregestational or gestational diabetes mellitus is another common situation in which fetal development encounters a hostile environment. Hyperglycemia in utero may trigger metabolic conditions in the offspring, including abnormalities of glucose tolerance and weight excess. Physicians assisting pregnant women have to be aware about these conditions, because they may go unnoticed if not properly screened. Because an early diagnosis and appropriate management may prevent most of the possible negative consequences for the progeny, the prevention, early diagnosis, and proper management of these endocrine conditions should be offered to all women undergoing pregnancy. Here, we comprehensively review the current evidence about the effects of maternal thyroid dysfunction and maternal dysglycemia on the cognitive function and carbohydrate metabolism in the offspring, two prevalent conditions of utmost importance for the child's health and development.

Effects of maternal B12 supplementation on neurophysiological outcomes in children: a study protocol for an extended follow-up from a placebo randomised control trial in Bangalore, India

INTRODUCTION

Vitamin B12 deficiency is highly prevalent in pregnant Indian women. Neuropsychological tests have shown an association between low maternal vitamin B12 status and poorer cognitive performances in the offspring, although findings from these studies have been inconsistent. Vitamin B12 has an important role in the formation of myelin which is important for the transmission speed of neural impulses and myelination in the central nervous system has been linked to cognition. Assessing neurophysiological measures using event-related potentials (ERPs) in children may provide additional information on the effect of maternal vitamin B12 supplementation on offspring brain function. The study examines the effects of oral vitamin B12 daily supplements (50 µg) to pregnant Indian women on child neurophysiological function at 72 months.

METHODS AND ANALYSIS

We previously conducted a double-blind, placebo-controlled study to examine the effects of maternal vitamin B12 supplementation on cognitive outcomes in their offspring using the Bayley scales of infant development, third edition. In this extended follow-up of the same cohort of mother-child dyad, we propose to use ERP to study the long-term impact of maternal B12 supplementation on brain function in children at 72 months of age. We intend to use P300 and mismatch negativity (MMN) as measures of neurophysiological outcomes. The primary outcome of this study will be child neurophysiological measures (as measured by amplitude and latency of P300 and MMN) assessed at 72 months of age in children whose mothers received vitamin B12 compared with neurophysiological status of children whose mothers received placebo.

ETHICS AND DISSEMINATION

The study was approved by the Institutional Ethical Board of St. John's Medical College and the Harvard School of Public Health Human Subjects Committee. Results obtained will be presented at national and international research meetings and published in peer-reviewed scientific journals.

TRIAL REGISTRATION NUMBER

NCT00641862.

Visual evoked potentials in offspring born to mothers with overweight, obesity and gestational diabetes

Background

Overweight, obesity, and gestational diabetes (GD) during pregnancy may negatively affect neurodevelopment in the offspring. However, the mechanisms are unclear and objective measures of neurodevelopment in infancy are scarce. We hypothesized that these maternal metabolic pathologies impair cortical visual evoked potentials (cVEPs), a proxy for visual and neuronal maturity.

Design

The PREOBE study included 331 pregnant women stratified into four groups; normal weight (controls), overweight, obesity, and GD (the latter including mothers with normal weight, overweight and obesity). In a subsample of the offspring at 3 months (n = 157) and at 18 months (n = 136), we assessed the latencies and amplitudes of the P100 wave from cVEPs and calculated visual acuity.

Results

At 3 months of age, visual acuity was significantly poorer in offspring born to GD mothers. At 18 months of age, there were no differences in visual acuity but infants born to GD mothers had significantly longer latencies of cVEPs when measured at 15’, and 30’ of arc. The group differences at 30’ remained significant after confounder adjustment (mean [SD] 121.0 [16.0] vs. 112.6 [7.6] ms in controls, p = 0.007) and the most prolonged latencies were observed in offspring to GD mothers with concurrent overweight (128.9 [26.9] ms, p = 0.002) and obesity (118.5 [5.1] ms, p = 0.020).

Conclusions

Infants born to mothers with GD, particularly those with concurrent overweight or obesity, have prolonged latencies of visual evoked potentials at 18 months of age, suggesting that this maternal metabolic profile have a long lasting, non-optimal, effect on infants´ brain development.

Atypical fetal development: Fetal alcohol syndrome, nutritional deprivation, teratogens, and risk for neurodevelopmental disorders and psychopathology

Accumulating evidence indicates that the fetal environment plays an important role in brain development and sets the brain on a trajectory across the life span. An abnormal fetal environment results when factors that should be present during a critical period of development are absent or when factors that should not be in the developing brain are present. While these factors may acutely disrupt brain function, the real cost to society resides in the long-term effects, which include important mental health issues. We review the effects of three factors, fetal alcohol exposure, teratogen exposure, and nutrient deficiencies, on the developing brain and the consequent risk for developmental psychopathology. Each is reviewed with respect to the evidence found in epidemiological and clinical studies in humans as well as preclinical molecular and cellular studies that explicate mechanisms of action.

The Influence of Gestational Diabetes on Neurodevelopment of Children in the First Two Years of Life: A Prospective Study

OBJECTIVE

Analyze the relation of gestational diabetes and maternal blood glucose levels to early cognitive functions in the first two years of life.

METHODS

In a prospective Singaporean birth cohort study, pregnant women were screened for gestational diabetes at 26-28 weeks gestation using a 75-g oral glucose tolerance test. Four hundred and seventy three children (n = 74 and n = 399 born to mothers with and without gestational diabetes respectively) underwent neurocognitive assessments at 6, 18, and/or 24 month, including electrophysiology during an attentional task and behavioral measures of attention, memory and cognition.

RESULTS

Gestational diabetes is related to left hemisphere EPmax amplitude differences (oddball versus standard) at both six (P = 0.039) and eighteen months (P = 0.039), with mean amplitudes suggesting offspring of mothers with gestational diabetes exhibit greater neuronal activity to standard stimuli and less to oddball stimuli. Associations between 2-hour maternal glucose levels and the difference in EPmax amplitude were marginal at 6 months [adjusted β = -0.19 (95% CI: -0.42 to +0.04) μV, P = 0.100] and significant at 18 months [adjusted β = -0.27 (95% CI: -0.49 to -0.06) μV, P = 0.014], and the EPmax amplitude difference (oddball-standard) associated with the Bayley Scales of Infant and toddler Development-III cognitive score at 24 months [β = 0.598 (95% CI: 0.158 to 1.038), P = 0.008].

CONCLUSION

Gestational diabetes and maternal blood glucose levels are associated with offspring neuronal activity during an attentional task at both six and eighteen months. Such electrophysiological differences are likely functionally important, having been previously linked to attention problems later in life.

Suggested use of sensitive measures of memory to detect functional effects of maternal iodine supplementation on hippocampal development

Maternal hypothyroxinemia secondary to iodine deficiency may have neurodevelopmental effects on the specific neurocognitive domain of memory. Associated disruption of thyroid hormone-dependent protein synthesis in the hippocampus has the potential to result in compromised development of the structure with consequential impairments in memory function. Despite links between maternal iodine deficiency during gestation and lactation and abnormal hippocampal development in rat fetuses and pups, there has been little research on the specific function of memory in human infants and young children born to iodine-deficient mothers. Several candidate measures have proven to be sensitive to the effects of gestational iron deficiency on memory function in infants and young children, including habituation and dishabituation, imitation-based tasks, and event-related potentials. Such measures could be used to test the effects of maternal iodine supplementation on the specific neurocognitive domain of memory in infants and young children. Furthermore, progress in understanding the effects of maternal iodine supplementation on neurocognitive development could be accelerated by the development of a nonhuman primate model to complement the rodent model.

Diabetes in Pregnancy and Childhood Cognitive Development: A Systematic Review

CONTEXT

The effect of diabetes during pregnancy on the cognitive development of offspring is unclear because of inconsistent findings from limited studies.

OBJECTIVE

This review was aimed to provide the best available scientific evidence on the associations between maternal pregnancy diabetes and the cognitive development of offspring.

DATA SOURCES

A search was conducted in the Embase, CINAHL, PubMed, PsycINFO, and Scopus databases.

STUDY SELECTION

Studies addressing the cognitive development of offspring (aged ≤12 years) as outcome and any diabetes in pregnancy as an exposure were included.

DATA EXTRACTION

Data were extracted and evaluated for quality by 2 independent reviewers.

RESULTS

Fourteen articles were eligible for the review. Ten studies investigated the associations between maternal pregestational diabetes or both pregestational and gestational diabetes and offspring's cognitive development; 6 studies found at least 1 negative association. Four studies exclusively examined the relationships between gestational diabetes and offspring's cognitive development; 2 studies found a negative association, 1 a positive association, and 1 a null association. The use of diverse cognitive and diabetes assessment tools/criteria, as well as statistical power, contributed to the inconsistent findings.

LIMITATIONS

The English-language restriction and publication bias in the included studies are potential limitations.

CONCLUSIONS

Although there are few data available regarding the associations between maternal pregnancy diabetes and offspring's cognitive development, this review found that maternal diabetes during pregnancy seems to be negatively associated with offspring's cognitive development. Large prospective studies that address potential confounders are needed to confirm the independent effect of maternal diabetes during pregnancy.

Maternal Diabetes and Cognitive Performance in the Offspring: A Systematic Review and Meta-Analysis

Objective

Diabetes during gestation is one of the most common pregnancy complications associated with adverse health effects for the mother and the child. Maternal diabetes has been proposed to negatively affect the cognitive abilities of the child, but experimental research assessing its impact is conflicting. The main aim of our study was to compare the cognitive function in children of diabetic and healthy pregnant women.

Methods

A systematic review and meta-analysis was conducted through a literature search using different electronic databases from the index date to January 31, 2015. We included studies that assessed the cognitive abilities in children (up to 14 years) of diabetic and non-diabetic mothers using standardized and validated neuropsychological tests.

Results

Of 7,698 references reviewed, 12 studies involving 6,140 infants met our inclusion criteria and contributed to meta-analysis. A random effect model was used to compute the standardized mean differences and 95% confidence interval (CI) were calculated. Infants (1–2 years) of diabetic mothers had significantly lower scores of mental and psychomotor development compared to control infants. The effect size for mental development was -0.41 (95% CI -0.59, -0.24; p<0.0001) and for psychomotor development was -0.31 (95% CI -0.55, -0.07; p = 0.0125) with non-significant heterogeneity. Diabetes during pregnancy could be associated with decreased intelligence quotient scores in school-age children, although studies showed significant heterogeneity.

Conclusion

The association between maternal diabetes and deleterious effects on mental/psychomotor development and overall intellectual function in the offspring must be taken with caution. Results are based on observational cohorts and a direct causal influence of intrauterine hyperglycemia remains uncertain. Therefore, more trials that include larger populations are warranted to elucidate whether gestational diabetes mellitus (GDM) has a negative impact on offspring central nervous system (CNS).

Neuropsychological Impairment in School-Aged Children Born to Mothers With Gestational Diabetes

The aim of this study was to determine whether school-aged children born to mothers with gestational diabetes show delays in their neuropsychological development. Several key neuropsychological characteristics of 32 children aged 7 to 9 years born to mothers with gestational diabetes were examined by comparing their performance on cognitive tasks to that of 28 children aged 8 to 10 years whose mothers had glucose levels within normal limits during pregnancy. The gestational diabetes group showed low performance on graphic, spatial, and bimanual skills and a higher presence of soft neurologic signs. Lower scores for general intellectual level and the working memory index were also evident. Our results suggest that gestational diabetes is associated with mild cognitive impairment.

Functional and Anatomic Consequences of Diabetic Pregnancy on Memory in Ten-Year-Old Children

OBJECTIVE

Pregnancies complicated by diabetes mellitus impair offspring memory functions during infancy and early childhood. The purpose of this study was to investigate the long-term consequences of such pregnancies on memory and memory-related brain regions in 10-year-old children.

METHODS

Nineteen children of diabetic mothers (CDMs) and 35 children of nondiabetic mothers participated in this 10-year follow-up study. Memory performance was assessed using a continuous recognition memory task during which children made old/new judgments in response to pictures of concrete and abstract objects presented after different lags or delays. In addition, the volume of the hippocampal formation (HF) was measured using high-resolution structural images.

RESULTS

At 10 years of age, recognition memory performance of CDMs did not differ from children of nondiabetic mothers. Similarly, the volume of the HF did not differ between groups. However, the size of the HF in CDMs predicted the time those children needed to provide accurate responses in the continuous recognition memory task.

CONCLUSIONS

CDMs do not show memory impairments by 10 years of age, despite evidence for such impairments early in life. However, subtle differences in underlying neural processes may still be present. These results have important implications for long-term cognitive development of CDMs.

Effect of maternal diabetes on the embryo, fetus, and children: congenital anomalies, genetic and epigenetic changes and developmental outcomes

INTRODUCTION

Pregestational and gestational diabetes mellitus (PGDM; GDM) are significant health concerns because they are associated with an increased rate of malformations and maternal health complications.

METHODS

We reviewed the data that help us to understand the effects of diabetes in pregnancy.

RESULTS

Diabetic embryopathy can affect any developing organ system, but cardiovascular and neural tube defects are among the most frequent anomalies. Other complications include preeclampsia, preterm delivery, fetal growth abnormalities, and perinatal mortality. Neurodevelopmental studies on offspring of mothers with diabetes demonstrated increased rate of Gross and Fine motor abnormalities, of Attention Deficit Hyperactivity Disorder, learning difficulties, and possibly also Autism Spectrum Disorder. The mechanisms underlying the effects of maternal hyperglycemia on the developing fetus may involve increased oxidative stress, hypoxia, apoptosis, and epigenetic changes. Evidence for epigenetic changes are the following: not all progeny are affected and not to the same extent; maternal diet may influence pregnancy outcomes; and maternal diabetes alters embryonic transcriptional profiles and increases the variation between transcriptomic profiles as a result of altered gene regulation. Research in animal models has revealed that maternal hyperglycemia is a teratogen, and has helped uncover potential therapeutic targets which, when blocked, can mitigate or ameliorate the negative effects of diabetes on the developing fetus.

CONCLUSIONS

Tight metabolic control, surveillance, and labor management remain the cornerstone of care for pregnant women with diabetes, but advances in the field indicate that new treatments to protect the mother and baby are not far from becoming clinical realities.

Prenatal choline supplementation ameliorates the long-term neurobehavioral effects of fetal-neonatal iron deficiency in rats

BACKGROUND

Gestational iron deficiency in humans and rodents produces long-term deficits in cognitive and socioemotional function and alters expression of plasticity genes in the hippocampus that persist despite iron treatment. Prenatal choline supplementation improves cognitive function in other rodent models of developmental insults.

OBJECTIVE

The objective of this study was to determine whether prenatal choline supplementation prevents the long-term effects of fetal-neonatal iron deficiency on cognitive and social behaviors and hippocampal gene expression.

METHODS

Pregnant rat dams were administered an iron-deficient (2-6 g/kg iron) or iron-sufficient (IS) (200 g/kg iron) diet from embryonic day (E) 3 to postnatal day (P) 7 with or without choline supplementation (5 g/kg choline chloride, E11-18). Novel object recognition (NOR) in the test vs. acquisition phase, social approach (SA), and hippocampal mRNA expression were compared at P65 in 4 male adult offspring groups: formerly iron deficient (FID), FID with choline supplementation (FID-C), IS, and IS with choline supplementation.

RESULTS

Relative to the intact NOR in IS rats (acquisition: 47.9%, test: 60.2%, P < 0.005), FID adult rats had impaired recognition memory at the 6-h delay (acquisition: 51.4%, test: 55.1%, NS), accompanied by a 15% reduction in hippocampal expression of brain-derived neurotrophic factor (Bdnf) (P < 0.05) and myelin basic protein (Mbp) (P < 0.05). Prenatal choline supplementation in FID rats restored NOR (acquisition: 48.8%, test: 64.4%, P < 0.0005) and increased hippocampal gene expression (FID-C vs. FID group: Bdnf, Mbp, P < 0.01). SA was also reduced in FID rats (P < 0.05 vs. IS rats) but was only marginally improved by prenatal choline supplementation.

CONCLUSIONS

Deficits in recognition memory, but not social behavior, resulting from gestational iron deficiency are attenuated by prenatal choline supplementation, potentially through preservation of hippocampal Bdnf and Mbp expression. Prenatal choline supplementation may be a promising adjunct treatment for fetal-neonatal iron deficiency.

Research review: maternal prenatal distress and poor nutrition - mutually influencing risk factors affecting infant neurocognitive development

BACKGROUND

Accumulating data from animal and human studies indicate that the prenatal environment plays a significant role in shaping children's neurocognitive development. Clinical, epidemiologic, and basic science research suggests that two experiences relatively common in pregnancy - an unhealthy maternal diet and psychosocial distress - significantly affect children's future neurodevelopment. These prenatal experiences exert their influence in the context of one another and yet, almost uniformly, are studied independently.

SCOPE AND METHOD OF REVIEW

In this review, we suggest that studying neurocognitive development in children in relation to both prenatal exposures is ecologically most relevant, and methodologically most sound. To support this approach, we selectively review two research topics that demonstrate the need for dual exposure studies, including exemplar findings on (a) the associations between pregnant women's inadequate maternal intake of key nutrients - protein, fat, iron, zinc, and choline - as well as distress in relation to overlapping effects on children's neurocognitive development; and (b) cross-talk between the biology of stress and nutrition that can amplify each experience for the mother and fetus,. We also consider obstacles to this kind of study design, such as questions of statistical methods for 'disentangling' the exposure effects, and aim to provide some answers.

CONCLUSION

Studies that specifically include both exposures in their design can begin to determine the relative and/or synergistic impact of these prenatal experiences on developmental trajectories - and thereby contribute most fully to the understanding of the early origins of health and disease.

Atypical fetal response to the mother's voice in diabetic compared with overweight pregnancies

OBJECTIVE

To characterize fetal spontaneous heart rate changes and movements and auditory-elicited heart rate changes in fetuses in diabetic pregnancies compared with those in uneventful, overweight pregnancies.

METHODS

Spontaneous heart rate and movements and maternal voice-elicited heart rate changes were observed in 46 mother-fetal pairs (n = 14 gestational diabetic and n = 32 overweight prepregnancy) at 36 (±1) weeks gestational age. Fetal heart rate changes, body movements, and breathing movements were observed for 20 minutes while the mother was at rest. Subsequently, each fetus was presented with a 2-minute audio recording of the mother's voice using the following 6-minute procedure: 2 minutes no-voice baseline, 2 minutes voice presentation, and 2 minutes no-voice postvoice period; heart rate was recorded continuously.

RESULTS

There were no differences in spontaneous heart rate changes, body movements, or breathing movements between the 2 groups. Fetuses in the overweight group showed an increase in the heart rate during the playing of their mother's voice, whereas fetuses in the diabetic group showed no response.

CONCLUSIONS

Fetuses in overweight pregnancies responded to the mother's voice with an increase in the heart rate as has been reported previously in uneventful pregnancies. The lack of response to the mother's voice in fetuses in diabetic pregnancies may represent immature neural or auditory system development, an increased sensorineural threshold, and thyroid or iron deficiency.

Cortical evoked potentials in children of diabetic mothers

Type 1 diabetic mothers' infants show a delay of visual evoked potential (VEP) significantly related to some parameters of poor metabolic control during pregnancy. In the present paper we analyzed the characteristics of VEPs and somatosensory evoked potentials (SEPs) recorded in 16 three-year-old type 1 diabetic mothers' children (DMC). Compared with controls (23 nondiabetic mothers' healthy matched children), DMC showed significantly delayed mean latency of VEP (P2) and SEP (P22). In 3 cases (19%), we found pathological responses (+3 SD from the mean value of controls) of VEPs and SEPs. At the age of 3 years, the offspring of type 1 diabetic mothers showed delay of cortical evoked responses in both visual and somatosensory systems.

Developmental considerations in working with newborn infants of mothers with diabetes

Infants of diabetic mothers (IDMs) are at risk for an altered developmental course beginning with physiologic alterations in utero. This article describes physiologic and behavioral factors that impact the fetus and newborn infant and may have long-term developmental consequences. A clinical reasoning process to support development optimizes the outcomes of IDMs while in the NICU. Specific interventions are suggested.

Atypical fetal voice processing in preeclamptic pregnancy

OBJECTIVE

To compare fetal heart rate (HR) response to the mother's voice in pregnancies complicated by preeclampsia with those of fetuses in uneventful, normotensive pregnancies.

METHOD

Fifty fetuses (n = 22, preeclampsia; n = 28, uneventful, normotensive pregnancies) between 32 and 40 weeks gestational age were recruited. Each fetus was presented with a 2-min no-sound baseline period followed by a 2-min voice period during which an audio recording of his/her mother reading a story was played through a loud speaker over the maternal abdomen at an average of 95 dBA followed by a 2-min no-voice offset period. HR was recorded continuously.

RESULTS

Fetuses in the preeclamptic group showed no response to the mother's voice when it was played. In comparison, fetuses in the uneventful, normotensive group responded to the mother's voice with a HR increase.

CONCLUSION

Fetuses in pregnancies complicated by preeclampsia show atypical auditory processing of the mother's voice. Such atypical responding may reflect a delay in auditory system maturation, functional elevation of sensorineural threshold, or decreased thyroid hormone.

Iron, Lead, and Children's Behavior and Cognition

Iron deficiency (ID) is the most common micronutrient deficiency in the world, with consequences of ID and ID anemia (IDA) in young children including behavioral and cognitive deficits. In turn, lead exposure is one of the most common environmental toxicants affecting children. Elevated blood lead levels (BLLs) in young children are also associated with behavioral and cognitive deficits. The metabolic and physiological connections between iron and lead, including a common route of entry into the body and similar neural targets, suggest a considerable overlap in their effects on functional outcomes. Very few studies have examined the existence of increased susceptibility to lead neurotoxicity in children with ID, but there is evidence that ID and BLL are independently associated with cognition and behavior. Children's susceptibility to both ID and elevated BLLs will likely depend on the timing and severity of both exposures, something that should be investigated systematically.

Delayed alternation performance in rats following recovery from early iron deficiency

Early iron deficiency (ID) is one of the most common nutrient deficiencies in both developed and developing countries. This condition has been linked to perturbations in myelin formation, alterations of monoamine neurotransmitter systems particularly in the striatum, and deficits in energy metabolism particularly in the hippocampus (HP) and prefrontal cortex (PFC) in rats. Early ID has also been traced to long-term behavioral consequences in children in domains linked to these neuropathologies. The current experiment assesses formerly iron deficient (FID) adult rats on a delayed alternation (DA) task - a procedure thought to be sensitive to PFC dysfunction. Rat dams were started on an iron deficient chow at gestational day (G) 2 and maintained on this diet until postnatal day (P) 7; behavioral training began at P 65 when animals were iron replete. FID animals exhibited accelerated acquisition (p=0.002) and fewer errors (p=0.003) on the DA task compared to controls. These findings may reflect an imbalance between hippocampal and prefrontal modulation of this behavior most likely emanating from long-term hippocampal disinhibition by early ID that persists in spite of early iron treatment from P 7.

Iron deficiency in infancy and neurocognitive functioning at 19 years: evidence of long-term deficits in executive function and recognition memory

Iron deficiency in infancy negatively impacts a variety of neurodevelopmental processes at the time of nutrient insufficiency, with persistent central nervous system alterations and deficits in behavioral functioning, despite iron therapy. In rodent models, early iron deficiency impairs the hippocampus and the dopamine system. We examined the possibility that young adults who had experienced chronic, severe, iron deficiency as infants would exhibit deficits on neurocognitive tests with documented frontostriatal (Trail Making Test, Intra-/Extra-dimensional Shift, Stockings of Cambridge, Spatial Working Memory, Rapid Visual Information Processing) and hippocampal specificity (Pattern Recognition Memory, Spatial Recognition Memory). Participants with chronic, severe iron deficiency in infancy performed less well on frontostriatal-mediated executive functions, including inhibitory control, set-shifting, and planning. Participants also exhibited impairment on a hippocampus-based recognition memory task. We suggest that these deficits may result from the long-term effects of early iron deficiency on the dopamine system, the hippocampus, and their interaction.

Consequences of low neonatal iron status due to maternal diabetes mellitus on explicit memory performance in childhood

Diabetic pregnancies are characterized by chronic metabolic insults, including iron deficiency, that place the developing brain at risk for memory impairment later in life. A behavioral recall paradigm coupled with electrophysiological measures was used to assess the longevity of these effects in 40 3(1/2)-year-old children. When memory demands were high, recall was significantly impaired in the at-risk group and correlated with perinatal measures of iron. Electrophysiological results suggested both encoding and retrieval processes were compromised. These findings support the hypothesis that prenatal iron deficiency leads to alterations in neural development that have a lasting impact on memory ability.

Maternal arachidonic acid supplementation improves neurodevelopment of offspring from healthy and diabetic rats

Maternal diabetes may compromise infant arachidonic acid status and development. This study tested if maternal arachidonic acid supplementation improves neurodevelopment in rat offspring. Dams were randomized into 6 groups using a 3x2 design: Saline-Placebo, streptozotocin-induced diabetes with glucose controlled at <13mmol/L, or poorly controlled at 13-20mmol/L using insulin; and fed either control or an arachidonic acid (0.5% of fat) diet throughout reproduction. Offspring were tested on post-natal days 3 and 5 for righting response, days 7 and 9 for negative geotaxis, day 14 for wire hanging endurance, days 18 and 24 for rota rod endurance, and day 28 for Morris water maze performance. Only the poorly controlled group had impaired day 7 geotaxis and day 18 rota rod performance (p<0.02), but this improved with maternal arachidonic acid supplementation (p<0.0006). Arachidonic acid improved the wire hanging endurance (p=0.0003) and water maze latency (p=0.0021), suggesting enhanced neurodevelopment in all offspring.

Fetal and neonatal habituation in infants of diabetic mothers

OBJECTIVE

To evaluate whether maternal diabetes alters the habituation ability of fetuses and newborns.

STUDY DESIGN

Two nonrandomized clinical trials were performed. First, we studied prenatal fetuses of women with pregestational diabetes, and control subjects matched for gestational age, and then we studied infants of diabetic mothers (IDM) and control subjects matched for gestational age and mode of delivery. Fetus and newborns were stimulated with vibroacoustic stimulus.

RESULTS

In fetuses of diabetic mothers, the ability to habituate was lower, and the habituation rate was higher than in control subjects to all habituation tests. In the neonatal period, ability to habituate was lower (59% vs 100%; P< .001), and the habituation rate was higher (18 [14-21] vs 4 [1.2-6.8]; P< .001) in the IDM than in the control infants. We found a significant negative correlation between maternal glycosylated hemoglobin in each trimester of pregnancy and habituation ability in IDM.

CONCLUSIONS

Fetuses and infants of diabetic mothers have impaired habituation ability, which is related to the degree of maternal metabolic control.

TYPE 1 DIABETES IN PREGNANCY; INFLUENCES ON MOTHER AND FETUS

Type 1 diabetes complicates around 1 in 200 to 300 pregnancies in the United Kingdom. Historically maternal type 1 diabetes carried very high risks for mother and child. Introduction of insulin led to an immediate, marked decline in the previously very high rates of maternal mortality; in contrast an improvement in perinatal outcomes occurred more slowly but was nevertheless dramatic. This is strikingly demonstrated by the temporal decline in perinatal mortality in offspring of mothers with type 1 diabetes which was virtually universal before use of insulin in the 1920's, likely remained in excess of 20% even in the 1960's and fell to under 4% by the 1990's. The reasons for this more gradual improvement in perinatal outcomes cannot be defined with precision but will have been influenced by improved glycaemic management with use of intensive, multiple dose insulin treatment and home glucose monitoring; improvements in obstetric and neonatal management, and better management of complications of diabetes before and during pregnancy. In 1989 the St Vincent declaration proposed that pregnancy outcomes in women with type 1 diabetes should approximate those of the non-diabetic population. While the long term improvements in fetal outcomes have been dramatic, contemporary surveys confirm a persistent doubling or more of rates of congenital anomaly and a three to four fold increase in perinatal mortality in the UK and other European countries which will require further clinical innovation to overcome.

Neural correlates of emotion processing in typically developing children and children of diabetic mothers

To examine the neurocognitive sequelae of children born to diabetic mothers (CDMs), event-related potentials (ERPs) in response to three facial expressions (happy, fear, anger) were collected from 42 children (18 CDMs, 24 controls), aged 36 and/or 48 months. A linear mixed models approach was used to model individual variation in amplitude and latency. As infants, CDMs in the present study displayed subtle impairments in attention and memory processing, including face recognition, as indexed by ERPs. Findings indicate that these same children, now ages 3-4 years, continue to display ERP patterns that differ from controls in amplitude, latency, and hemispheric asymmetry.

Use of event-related potentials in the study of typical and atypical development

A variety of neuroimaging tools are now available for use in studying neurodevelopment. In this article, we focus our attention on one such tool--the event-related potential (ERP). We begin by providing an overview of what ERPs are, their physiological basis, how they are recorded, and some constraints on their use. We then provide an abbreviated glossary of ERP components, that is, what processes are reflected in ERPs. We conclude by summarizing two areas of atypical development that have benefited from this method: children experiencing early psychosocial neglect, and children diagnosed with autism. We conclude by offering recommendations for future research.

Gestational diabetes hinders language development in offspring

BACKGROUND

Previous studies have suggested that language is affected in infants of diabetic mothers, yet there have been no systematic investigations to address this question.

OBJECTIVE

Our goal was to compare infants of diabetic mothers and controls on language outcomes from ages 18 months to 7 years.

METHODS

This was a case-control longitudinal design with 2 birth cohorts: 1835 singletons from the Quebec Longitudinal Study of Child Development (born October 1997 to July 1998) and 998 twins from the Quebec Newborn Twin Study (born November 1995 to July 1998). Cases were 221 infants of diabetic mothers (105 singletons and 116 twins), and controls were 2612 children (1730 singletons and 882 twins) for whom at least 1 language measure from ages 18 months to 7 years was available. Exclusion criteria were gestation of <32 weeks. The outcome measures were McArthur Communicative Development Inventory expressive and receptive vocabulary and grammar at 18 months and 30 months, the Peabody Picture Vocabulary Test receptive vocabulary at 48 months and expressive and receptive vocabulary at 60 months, and Early Development Instrument teacher-assessed communication at 72 months and 84 months (kindergarten and first grade). RESULTS. Analyses of variance (controlling for gender, socioeconomic status, and perinatal factors) revealed effects of gestational diabetes on expressive language at 18, 30, and 72/84 months. Infants of diabetic mothers scored 0.27 to 0.41 SD lower than controls and were 2.2 times more at risk of a language impairment. Genes and maternal education both moderated the effect of gestational diabetes on expressive language during this period.

CONCLUSION

Gestational diabetes hinders expressive language in offspring into middle childhood. Genes are strongly associated with the risk of delays in infants of diabetic mothers, and offspring of educated mothers are less affected.

Iron deficiency and child development

Iron deficiency is widespread in infants and young children, especially in developing countries. Animal models provide convincing evidence that, despite iron repletion, iron deficiency during the brain growth spurt alters metabolism and neurotransmission, myelination, and gene and protein profiles. In the human, there is compelling evidence that 6- to 24-month-old infants with iron-deficiency anemia are at risk for poorer cognitive, motor, social-emotional, and neurophysiologic development in the short- and long-term outcome. In contrast to inconsistent developmental effects of iron therapy for iron-deficient infants, recent large, randomized trials of iron supplementation in developing countries uniformly show benefits of iron, especially on motor development and social-emotional behavior. These results indicate that adverse effects can be prevented and/or reversed with iron earlier in development or before iron deficiency becomes severe or chronic. New findings also point to the need for more attention to the developmental effects of prenatal iron deficiency.

Randomized trial of early versus late enteral iron supplementation in infants with a birth weight of less than 1301 grams: neurocognitive development at 5.3 years' corrected age

BACKGROUND

Iron deficiency in early childhood may impair neurodevelopment. In a masked, randomized, controlled trial of early versus late enteral iron supplementation in preterm infants with birth weights of <1301 g, early iron supplementation reduced the incidence of iron deficiency and the number of blood transfusions.

OBJECTIVE

We sought to examine whether early enteral iron supplementation improves neurocognitive and motor development in these infants.

METHODS

Children who participated in the above mentioned trial were evaluated by applying the Kaufmann Assessment Battery for Children and the Gross Motor Function Classification Scale at the age of school entry.

RESULTS

Of the 204 infants initially randomized, 10 died and 30 were lost to follow-up. A total of 164 (85% of the survivors) were evaluated at a median corrected age of 5.3 years. In this population (n = 164), the mean (+/-SD) mental processing composite in the early iron group was 92 (+/-17) versus 89 (+/-16) in the late iron group. An abnormal neurologic examination was found in 17 of 90 versus 26 of 74, and a Gross Motor Function Classification Scale score of >1 was found in 2 of 90 versus 5 of 74, respectively. Fifty-nine of 90 children in the early iron group were without disability, compared with 40 of 74 in the late iron group. Severe disability was found in 5 of 90 versus 6 of 74 children and 67 of 90 versus 49 of 74 qualified for regular schooling, respectively.

CONCLUSIONS

Early enteral iron supplementation showed a trend toward a beneficial effect on long-term neurocognitive and psychomotor development and showed no evidence for any adverse effect. Because the initial study was not designed to evaluate effects on neurocognitive development, the power was insufficient to detect small but potentially clinically relevant improvements. Additional studies are required to confirm the trend towards a better outcome observed in the early iron group.

An event-related potential study of attention and recognition memory in infants with iron-deficiency anemia

OBJECTIVES

The purpose of this work was to determine whether iron-deficiency anemia in infancy represents a risk factor for deficits in attention and memory development using event-related potentials.

METHODS

Artifact-free event-related potential data were obtained at 9 and/or 12 months from 15 infants with iron-deficiency anemia and 19 who were iron sufficient during a test of the infant's ability to discriminate a highly familiar stimulus, the mother's face, from a stranger's face.

RESULTS

A midlatency negative component associated with attention and a late-occurring positive slow wave associated with memory updating were identified at both ages in the iron-deficiency anemia and iron-sufficient groups. Consistent with the age-appropriate pattern of development at 9 months, the iron-sufficient group showed a greater attentional response (negative component) to the mother and a greater updating of memory for the stranger (positive slow wave). This pattern of responses was not evident in the iron-deficiency anemia group until 12 months, suggesting a delay in cognitive development.

CONCLUSIONS

These data suggest that iron-deficiency anemia adversely affects the allocation of neurophysiologic resources to attention and recognition memory during the processing of information about familiar and unfamiliar stimuli. This delay in cognitive development may reflect alterations in efficiency of central nervous system functions that seem related to early iron deficiency.

Using event-related potentials to study perinatal nutrition and brain development in infants of diabetic mothers

Proper prenatal and postnatal nutrition is essential for optimal brain development and function. The early use of event-related potentials enables neuroscientists to study the development of cognitive function from birth and to evaluate the role of specific nutrients in development. Perinatal iron deficiency occurs in severely affected infants of diabetic mothers. In animal models, severe perinatal iron deficiency targets the explicit memory system of the brain. Cross-sectional ERP studies have shown that infants of diabetic mothers have impairments in recognition memory from birth through 8 months of age. The purpose of this study was to evaluate longitudinal development of recognition memory using ERPs in infants of diabetic mothers compared with control infants. Infants of diabetic mothers were divided into high and low risk status based upon their birth weights and iron status and compared with healthy control infants. Infants were tested in the newborn period for auditory recognition memory, at 6 months for visual recognition memory and at 8 months for cross modal memory. ERPs were evaluated for developmental changes in the slow waves that are thought to reflect memory and the Nc component that is thought to reflect attention. The results of the study showed differences in development between the IDMs and control infants in the development of the slow waves over the left anterior temporal leads and age-related patterns of development in the NC component. These results are consistent with animal models showing that perinatal iron deficiency affects the development of the memory networks of the brain. This study highlights the value of using ERPs to translate basic science information obtained from animal models to the development of the human infant.

Word and face recognition in children with congenital hypothyroidism: an event-related potential study

The repetition paradigm offers a useful technique for assessing recognition memory by evaluating how an individual responds to new versus old stimuli. While this paradigm has been extensively used in adults with and without clinical conditions, it has not, to our knowledge, been studied in a clinical pediatric population. Children with congenital hypothyroidism (CH) identified by newborn screening and treated early in life have normal intelligence but demonstrate residual cognitive deficits including selective memory problems that are attributed to their loss of thyroid hormone during hippocampal formation. Since the hippocampus is integral for recognition memory, we hypothesized that children with CH would perform atypically on the repetition paradigm. Event-related potentials (ERPs) were recorded during word and face recognition in nine children aged 11 to 13 years with CH and nine typically developing children matched for age. Results revealed that while the groups did not differ in accuracy or reaction time, they did differ significantly on selective ERP components. Like normal adults, the comparison children showed a positive elevation in P3 amplitude for repeated relative to new words at the parietal electrodes, whereas children with CH did not. Both groups produced weak repetition effects when viewing faces, although the amplitudes of children with CH were somewhat smaller. It is proposed that the dampened neurophysiological response to repeated verbal stimuli by children with CH may explain some of their clinically observed difficulties in short-term recognition memory.

Long-lasting neural and behavioral effects of iron deficiency in infancy

Infants are at high risk for iron deficiency and iron-deficiency anemia. This review summarizes evidence of long-term effects of iron deficiency in infancy. Follow-up studies from preschool age to adolescence report poorer cognitive, motor, and social-emotional function, as well as persisting neurophysiologic differences. Research in animal models points to mechanisms for such long-lasting effects. Potential mechanisms relate to effects of iron deficiency during brain development on neurometabolism, myelination, and neurotransmitter function.