Prenatal Iron Deficiency, Neonatal Ferritin, and Infant Cognitive Function

Association between maternal haemoglobin status during pregnancy and children's mental and psychomotor development at 18 months of age: Evidence from rural Bangladesh

BACKGROUND

Anaemia is commonly caused by iron deficiency and screened by haemoglobin (Hb) concentration in blood. There is a scarcity of longitudinal data on the relationship between maternal Hb levels during pregnancy and neurodevelopment in children.

OBJECTIVE

To measure the relationship of maternal Hb concentrations during pregnancy on early child development.

METHODS

This prospective cohort study included 1,720 mother-child dyads in rural Bangladesh. Maternal Hb concentrations were measured at 14 and 30 weeks of gestation. The child's Mental Developmental Index (MDI) and Psychomotor Developmental Index (PDI) at 18 months of age were measured using Bayley Scales of Infant and Toddler Development (BSID-II). Data on socio-demographic characteristics, anthropometrics, mothers' IQ and children's home stimulation were also collected. Bivariate and multivariable-adjusted linear regression analyses were used to explore associations of maternal Hb with child development.

RESULTS

Mean Hb concentrations at 14 and 30 weeks of gestation were 116.6 g/L (±12.7) and 114.7 g/L (±12.7), respectively. Mean MDI and PDI scores among 18-month-old children were 78.9 (±12.4) and 93.8 (±13.7), respectively. Maternal 14-week Hb concentration was correlated with PDI (r = 0.06; p < 0.05) and 30-week Hb concentrations was correlated with MDI (r = 0.05; p < 0.05). Multivariable adjusted linear regression analysis showed that an increase in 14-week Hb concentrations increased the PDI scores among boys (β = 0.09; 95% CI: 0.02, 0.16). Hb concentrations at 30 weeks of gestation were not associated with MDI or PDI scores.

CONCLUSION

Higher maternal Hb concentrations at 14 weeks of gestation were associated with higher PDI among 18-month-old boys in Bangladesh.

Exploring the association between haematological markers of iron and general movements in 4-month-old infants exposed to anaemia in-utero

BACKGROUND

Iron is a vital micronutrient for brain development, influencing myelination, neurotransmitter balance, and the maturation of specific brain cells. Hence iron insufficiency in the foetal, neonatal and infancy period has the potential to influence the neuromotor development.

AIMS

We aimed to describe haematological markers of iron at 4 months of age in infants exposed to prenatal anaemia and explore the association with their quality of general movements.

STUDY DESIGN

Cross sectional study nested within the RAPIDIRON-KIDS trial.

SUBJECTS

All infants whose mothers were part of RAPIDIRON-KIDS trial, were eligible to participate in this study when the infants were 4 months old. Children suffering from fever or acute illness on the day of assessment, or with a history of either surgery, or admission to hospital in the first month were excluded.

OUTCOME MEASURES

Haematological markers of iron (Haemoglobin and Ferritin level) and quality of general movements in infants at 4 months of age.

RESULTS

120 infants were assessed with mean birth weight of 2685.5 g (±384.5) and median gestational age of 39 weeks [Q1, Q3:38,40]. There was no significant association between haemoglobin or ferritin levels with fidgety movements (p = 0.18 and p = 0.27, respectively). The combined effect of haemoglobin and ferritin estimates also did not show any significant association with the study groups (p = 0.21).

CONCLUSION

A majority of infants still had low iron indices at 4 months of age and this was not associated with the quality of general movements. A prospective longitudinal study needs to be considered in infants exposed to prenatal anaemia rather than assessing the outcomes at a single time point.

A district-level geospatial analysis of anaemia prevalence among rural men in India, 2019-21

BACKGROUND

Despite its considerable impact on health and productivity, anemia among men has received limited attention. In a country as diverse as India, characterized by extensive geographic variations, there is a pressing need to investigate the nuanced spatial patterns of anemia prevalence among men. The identification of specific hotspots holds critical implications for policymaking, especially in rural areas, where a substantial portion of India's population resides.

METHODS

The study conducted an analysis on a sample of 61,481 rural men from 707 districts of India, utilizing data from the National Family Health Survey-5 (2019-21). Various analytical techniques, including Moran's I, univariate LISA (Local Indicators of Spatial Association), bivariate LISA, and spatial regression models such as SLM (Spatial Lag Model), and SEM (Spatial Error Model) were employed to examine the geographic patterns and spatial correlates of anaemia prevalence in the study population.

RESULTS

In rural India, three out of every ten men were found to be anemic. The univariate Moran's I value for anaemia was 0.66, indicating a substantial degree of spatial autocorrelation in anaemia prevalence across the districts in India. Cluster and outlier analysis identified five prominent 'hotspots' of anaemia prevalence across 97 districts, primarily concentrated in the eastern region (encompassing West Bengal, Jharkhand, and Odisha), the Dandakaranya region, the Madhya Pradesh-Maharashtra border, lower Assam, and select districts in Jammu and Kashmir. The results of SLM revealed significant positive association between anaemia prevalence at the district-level and several key factors including a higher proportion of Scheduled Tribes, men in the 49-54 years age group, men with limited or no formal education, individuals of the Muslim faith, economically disadvantaged men, and those who reported alcohol consumption.

CONCLUSIONS

Substantial spatial heterogeneity in anaemia prevalence among men in rural India suggests the need for region-specific targeted interventions to reduce the burden of anaemia among men in rural India and enhance the overall health of this population.

Gender-specific association between serum ferritin and neurodevelopment in infants aged 6 to 12 months

Early iron deficiency has detrimental consequences on neurodevelopment; whether male and female infants are equally susceptible to the functional outcomes of iron deficiency is unclear. This study aimed to investigate the sex differences in the association between serum ferritin levels and neurodevelopment in infants. Data for this cross-sectional study were drawn from hospital information and early childhood development program service systems at Guangdong Women and Children's Hospital, Guangzhou, China. In total, 4579 infants aged 6-12 months were included from July 2018 to March 2020. Their neurodevelopment was assessed using the Children Neuropsychological and Behavior Scale-Revision 2016. Serum ferritin levels were measured by chemiluminescence assay. The association between serum ferritin levels and neurodevelopmental delay in each domain was estimated using logistic regression models adjusted for potential confounders. The mean concentration of serum ferritin was 35.56 ± 21.57 ng/mL. Serum ferritin levels were significantly higher in female than in male infants (P < 0.001). Iron deficiency (serum ferritin levels < 12 ng/mL) was significantly more prevalent in male than in female infants (P < 0.001). Linear regression revealed a positive association between serum ferritin levels and general quotient, gross motor, fine motor, language, and adaptive behavior in females. Iron deficiency was significantly associated with an increased risk of adaptive behavior delay in females (adjusted odds ratio (OR), 2.22; 95% confidence interval (CI): 1.17-4.20). Iron deficiency anemia was associated with an increased risk of developmental delay for general quotient (adjusted OR, 4.88; 95% CI: 1.74-13.65), fine motor (adjusted OR = 2.58, 95%: CI: 1.13-5.94) and adaptive behavior (adjusted OR, 3.38; 95% CI: 1.51-7.57) among females, but not in males. Associations between serum ferritin levels and neurodevelopment in infants aged 6-12 months were sex-related. Females with iron deficiency, especially those with iron-deficiency anemia, were more susceptible to neurodevelopmental delay than males.

Iron Metabolism and Ferroptosis in Physiological and Pathological Pregnancy

Iron is a vital element in nearly every living organism. During pregnancy, optimal iron concentration is essential for both maternal health and fetal development. As the barrier between the mother and fetus, placenta plays a pivotal role in mediating and regulating iron transport. Imbalances in iron metabolism correlate with severe adverse pregnancy outcomes. Like most other nutrients, iron exhibits a U-shaped risk curve. Apart from iron deficiency, iron overload is also dangerous since labile iron can generate reactive oxygen species, which leads to oxidative stress and activates ferroptosis. In this review, we summarized the molecular mechanism and regulation signals of placental iron trafficking under physiological conditions. In addition, we revealed the role of iron metabolism and ferroptosis in the view of preeclampsia and gestational diabetes mellitus, which may bring new insight to the pathogenesis and treatment of pregnancy-related diseases.

Oxidative Stress in Malaria: Potential Benefits of Antioxidant Therapy

Malaria is an infectious disease and a serious public health problem in the world, with 3.3 billion people in endemic areas in 100 countries and about 200 million new cases each year, resulting in almost 1 million deaths in 2018. Although studies look for strategies to eradicate malaria, it is necessary to know more about its pathophysiology to understand the underlying mechanisms involved, particularly the redox balance, to guarantee success in combating this disease. In this review, we addressed the involvement of oxidative stress in malaria and the potential benefits of antioxidant supplementation as an adjuvant antimalarial therapy.

Low Hemoglobin Levels Are Associated with Reduced Psychomotor and Language Abilities in Young Ugandan Children

Children living in Sub-Saharan Africa are vulnerable to developmental delay, particularly in the critical first five years due to various adverse exposures including disease and nutritional deficiencies. Anemia and iron deficiency (ID) are highly prevalent in pregnant mothers and young children and are implicated in abnormal brain development. However, available evidence on the association between anemia, ID and neurodevelopment in sub-Saharan Africa is limited. Using data from the Entebbe Mother and Baby Study prospective birth cohort, we examined the effect of maternal and child hemoglobin (Hb) levels and child iron status on developmental scores in 933 and 530 pre-school Ugandan children respectively. Associations between Hb levels, iron status and developmental scores were assessed using regression analyses adjusting for potential confounders. Lower maternal and child Hb levels were associated with reduced psychomotor scores at 15 months, while only lower Hb levels in infancy were associated with reduced language scores. We found no evidence that anemia or ID was associated with cognitive or motor scores at five years. This study emphasizes the importance of managing anemia in pregnancy and infancy and highlights the need for further studies on the effects of anemia and ID in children living in Sub-Saharan Africa.

Diagnosis of children with attention-deficit/hyperactivity disorder (ADHD) comorbid autistic traits (ATs) by applying quantitative magnetic resonance imaging techniques

OBJECTIVE

To explore the feasibility of applying quantitative magnetic resonance imaging techniques for the diagnosis of children with attention-deficit/hyperactivity disorder (ADHD) comorbid autistic traits (ATs).

METHODS

A prospective study was performed by selecting 56 children aged 4-5 years with ADHD-ATs as the study group and 53 sex- and age-matched children with ADHD without ATs as the control group. All children underwent magnetic resonance scans with enhanced T2^*- weighted magnetic resonance angiography (ESWAN), 3D-PCASL, and 3D-T1 sequences. Iron content and cerebral blood flow parameters were obtained via subsequent software processing, and the parameter values in particular brain regions in both groups were compared and analyzed to determine the characteristics of these parameters in children with ADHD-ATs.

RESULTS

Iron content and cerebral blood flow in the frontal lobe, temporal lobe, hippocampus, and caudate nucleus of children with ADHD-ATs were lower than those of children with ADHD without ATs (p < 0.05). Iron content and CBF values in the frontal lobe, temporal lobe and caudate nucleus could distinguish children with ADHD-ATs from those without ATs (AUC > 0.5, p < 0.05).

CONCLUSIONS

Quantitative magnetic resonance techniques could distinguish children with ADHD-ATs.

TRIAL REGISTRATION

This study protocol was registered at the Chinese clinical trial registry (ChiCTR2100046616).

Effects of iron intake on neurobehavioural outcomes in African children: a systematic review and meta-analysis of randomised controlled trials

Background: Iron deficiency and developmental delay are common in African children. While experimental studies indicate an important role of iron in brain development, effects of iron on child development remain unclear. We aimed to evaluate the effects of iron supplementation or fortification on neurobehavioural outcomes in African children and further summarise these effects in children living in non-African countries for comparison. Methods: We searched PubMed, EMBASE, PsycINFO, Scopus and Cochrane Library for studies published up to 22 nd October 2021. We included randomised controlled trials (RCTs) evaluating effects of iron supplementation or fortification on neurobehavioural outcomes in children. Due to heterogeneity in study methods, we analysed all studies qualitatively and in secondary analyses only seven RCTs with 11 arms were meta-analysed. Results: We identified 2231 studies and included 35 studies (n=9988) in the systematic review. Only five studies (n=1294) included African children while 30 (n=8694) included children living in non-African countries. Of the five African studies, two (n=647) reported beneficial effects of iron supplementation on neurobehavioural outcomes in anaemic children, while three (n=647) found no beneficial effects. Of 30 studies in children living in non-African countries, 10 (n=3105) reported beneficial effects of iron supplementation or fortification on neurobehavioural outcomes, seven (n=786) reported beneficial effects only in children who had iron deficiency, iron deficiency anaemia or anaemia while 13 (n=4803) reported no beneficial effects. Conclusions: There are few studies in African children despite the high burden of iron deficiency and developmental delay in this population. Evidence on the effects of iron supplementation on neurobehavioural outcomes remains unclear and there is need for further well-powered studies evaluating these effects in African populations. PROSPERO registration: CRD42018091278 (20/03/2018).

Iron Deficiency Anemia in Pregnancy

Anemia is defined as a low red blood cell count, a low hematocrit, or a low hemoglobin concentration. In pregnancy, a hemoglobin concentration of less than 11.0 g/dL in the first trimester and less than 10.5 or 11.0 g/dL in the second or third trimester (depending on the guideline used) is considered anemia. Anemia is the most common hematologic abnormality in pregnancy. Maternal anemia is associated with adverse fetal, neonatal and childhood outcomes, but causality is not established. Maternal anemia increases the likelihood of transfusion at delivery. Besides hemodilution, iron deficiency is the most common cause of anemia in pregnancy. The American College of Obstetricians and Gynecologists recommends screening for anemia with a complete blood count in the first trimester and again at 24 0/7 to 28 6/7 weeks of gestation. Mild anemia, with a hemoglobin of 10.0 g/dL or higher and a mildly low or normal mean corpuscular volume (MCV) is likely iron deficiency anemia. A trial of oral iron can be both diagnostic and therapeutic. Mild anemia with a very low MCV, macrocytic anemia, moderate anemia (hemoglobin 7.0-9.9 g/dL) or severe anemia (hemoglobin 4.0-6.9 g/dL) requires further investigation. Once a diagnosis of iron deficiency anemia is confirmed, first-line treatment is oral iron. New evidence suggests that intermittent dosing is as effective as daily or twice-daily dosing with fewer side effects. For patients with iron deficiency anemia who cannot tolerate, cannot absorb, or do not respond to oral iron, intravenous iron is preferred. With contemporary formulations, allergic reactions are rare.

The effect of prepregnancy body mass index on maternal micronutrient status: a meta-analysis

The relationship between prepregnancy body mass index (BMI) and maternal micronutrient status is inconsistent and has not received sufficient attention. This meta-analysis aimed to evaluate the effect of prepregnancy BMI on micronutrient levels in pregnant women. PubMed, Embase, Web of Science, and the Cochrane Library were searched for articles that contained information on micronutrient levels and prepregnancy BMI. A random-effects model was used to determine the association between prepregnancy BMI and maternal micronutrient status. Sixty-one eligible articles were eventually included, with 83,554 participants. Vitamin B12, folate, vitamin D, iron and ferritin were the main micronutrients evaluated in our meta-analysis. Prepregnancy obesity and overweight may lead to an increased risk of micronutrient deficiency, including vitamin B12, folate and vitamin D deficiency, while prepregnancy obesity or overweight may have no significant association with ferritin deficiency. Additionally, the results of the dose-response analyses demonstrated a possible significant inverse correlation between prepregnancy BMI and levels of micronutrient, except for iron and ferritin. Compared with women with normal weight, women who were overweight or obese prepregnancy have lower micronutrient concentrations and are more likely to exhibit micronutrient deficiency during pregnancy, which is harmful to both mothers and neonates.

Effects of iron intake on neurobehavioural outcomes in African children: a systematic review and meta-analysis of randomised controlled trials

Background: Iron deficiency and developmental delay are common in African children. While experimental studies indicate an important role of iron in brain development, effects of iron on child development remain unclear. We aimed to evaluate the effects of iron supplementation or fortification on neurobehavioural outcomes in African children and further summarise these effects in children living in non-African countries for comparison. Methods: We searched PubMed, EMBASE, PsycINFO, Scopus and Cochrane Library for studies published up to 9 th March 2021. We included randomised controlled trials (RCTs) evaluating effects of iron supplementation or fortification on neurobehavioural outcomes in children. Due to heterogeneity in study methods, we analysed the studies qualitatively and only seven RCTs with 11 arms were meta-analysed. Results: We identified 2155 studies and included 34 studies (n=9808) in the systematic review. Only five studies (n=1294) included African children while 29 (n=8514) included children living in non-African countries. Of the five African studies, two (n=647) reported beneficial effects of iron supplementation on neurobehavioural outcomes in anaemic children while three (n=647) found no beneficial effects. Of 29 studies in children living in non-African countries, nine (n=2925) reported beneficial effects of iron supplementation or fortification on neurobehavioural outcomes, seven (n=786) reported beneficial effects only in children who had iron deficiency, iron deficiency anaemia or anaemia while 13 (n=4803) reported no beneficial effects. Meta-analysis of seven studies (n=775) in non-African countries showed no beneficial effects of iron supplementation on cognitive or motor development in children. Conclusions: There are few studies in African children despite the high burden of iron deficiency and developmental delay in this population. Evidence on the effects of iron supplementation on neurobehavioural outcomes remains unclear and there is need for further well-powered studies evaluating these effects in African populations. PROSPERO registration: CRD42018091278 (20/03/2018).

Maternal Iron Status in Pregnancy and Child Health Outcomes after Birth: A Systematic Review and Meta-Analysis

In pregnancy, iron deficiency and iron overload increase the risk for adverse pregnancy outcomes, but the effects of maternal iron status on long-term child health are poorly understood. The aim of the study was to systematically review and analyze the literature on maternal iron status in pregnancy and long-term outcomes in the offspring after birth. We report a systematic review on maternal iron status during pregnancy in relation to child health outcomes after birth, from database inception until 21 January 2021, with methodological quality rating (Newcastle-Ottawa tool) and random-effect meta-analysis. (PROSPERO, CRD42020162202). The search identified 8139 studies, of which 44 were included, describing 12,7849 mother–child pairs. Heterogeneity amongst the studies was strong. Methodological quality was predominantly moderate to high. Iron status was measured usually late in pregnancy. The majority of studies compared categories based on maternal ferritin, however, definitions of iron deficiency differed across studies. The follow-up period was predominantly limited to infancy. Fifteen studies reported outcomes on child iron status or hemoglobin, 20 on neurodevelopmental outcomes, and the remainder on a variety of other outcomes. In half of the studies, low maternal iron status or iron deficiency was associated with adverse outcomes in children. Meta-analyses showed an association of maternal ferritin with child soluble transferrin receptor concentrations, though child ferritin, transferrin saturation, or hemoglobin values showed no consistent association. Studies on maternal iron status above normal, or iron excess, suggest deleterious effects on infant growth, cognition, and childhood Type 1 diabetes. Maternal iron status in pregnancy was not consistently associated with child iron status after birth. The very heterogeneous set of studies suggests detrimental effects of iron deficiency, and possibly also of overload, on other outcomes including child neurodevelopment. Studies are needed to determine clinically meaningful definitions of iron deficiency and overload in pregnancy.

[Formula: see text]Neurodevelopmental assessment at one year of age predicts neuropsychological performance at six years in a cohort of West African Children

Rural children from Benin, west Africa were evaluated with the Mullen Scales of Early Learning (MSEL) at one year of age and then at six years with the Kaufman Assessment Battery for Children (KABC-II), the visual computerized Tests of Variables of Attention (TOVA), and the Bruininks-Oseretsky Test (BOT-2) of motor proficiency (N = 568). Although both the MSEL and KABC-II were available to the assessors in French, instructions to the mother/child were in local language of Fon. Mothers were evaluated with the Edinburgh Postpartum Depression Scale (EPDS), Caldwell HOME Scale, educational level and literacy, and a Socio-Economic Scale - also in their local language (Fon). After adjusting for maternal factors, MSEL cognitive composite was correlated with KABC-II with moderate effect sizes, but not with TOVA scores. Overall eta-squared effect for the multivariate models were moderately to strongly correlated (.07 to .37). Neurodevelopmental assessments in early childhood adapted cross-culturally are predictive of school-age neuropsychological cognitive ability.

Behavioral consequences at 5 y of neonatal iron deficiency in a low-risk maternal-infant cohort

BACKGROUND

Iron is critical to the developing brain, but fetal iron accretion is compromised by several maternal and pregnancy-related factors. Little consideration has been given to the long-term neurologic consequences of neonatal iron deficiency, especially in generally healthy, low-risk populations.

OBJECTIVE

We aimed to investigate the association between neonatal iron deficiency and neurologic development at 2 and 5 y of age.

DESIGN

We measured umbilical cord serum ferritin concentrations in the prospective maternal-infant Cork BASELINE (Babies after SCOPE: Evaluating the Longitudinal Impact Using Neurological and Nutritional Endpoints) Birth Cohort. Lifestyle and clinical data were collected from 15 weeks of gestation to 5 y of age. Standardized neurologic assessments were performed at 2 y [Bayley Scales of Infant Development/Child Behavior Checklist (CBCL)] and 5 y (Kaufman Brief Intelligence Test/CBCL).

RESULTS

Among 697 maternal-infant pairs, median (IQR) cord ferritin concentrations were 200.9 (139.0, 265.8) µg/L; 8% had neonatal iron deficiency (ferritin <76 µg/L). Using fully adjusted models, there was no association between neonatal iron deficiency and cognitive or behavioral outcomes at 2 or 5 y. We conducted an a priori sensitivity analysis in 306 high-risk children, selected using known risk factors for neonatal iron deficiency (smoking/obesity/cesarean section delivery/small-for-gestational age birth). In this high-risk subgroup, children with iron deficiency at birth (12%) had similar cognitive outcomes, but the behavioral assessments showed higher internalizing [9.0 (5.3, 12.0) compared with 5.0 (3.0, 10.0), P = 0.006; adjusted estimate (95% CI): 2.8 (0.5, 5.1), P = 0.015] and total [24.5 (15.3, 40.8) compared with 16.0 (10.0, 30.0), P = 0.009; adjusted estimate (95% CI): 6.6 (0.1, 13.1), P = 0.047] problem behavior scores at 5 y compared with those born iron sufficient.

CONCLUSIONS

We have demonstrated lasting behavioral consequences of neonatal iron deficiency in high-risk children from our generally healthy, low-risk maternal-infant cohort. Although larger investigations are warranted, this study provides strong association data to suggest that interventions and strategies targeting the fetal and neonatal period should be prioritized for the prevention of iron deficiency and associated neurologic consequences.

Beyond the Mind-Serum Trace Element Levels in Schizophrenic Patients: A Systematic Review

The alterations in serum trace element levels are common phenomena observed in patients with different psychiatric conditions such as schizophrenia, autism spectrum disorder, or major depressive disorder. The fluctuations in the trace element concentrations might act as potential diagnostic and prognostic biomarkers of many psychiatric and neurological disorders. This paper aimed to assess the alterations in serum trace element concentrations in patients with a diagnosed schizophrenia. The authors made a systematic review, extracting papers from the PubMed, Web of Science, and Scopus databases according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Among 5009 articles identified through database searching, 59 of them were assessed for eligibility. Ultimately, 33 articles were included in the qualitative synthesis. This review includes the analysis of serum levels of the following trace elements: iron, nickel, molybdenum, phosphorus, lead, chromium, antimony, uranium, magnesium, aluminum, zinc, copper, selenium, calcium, and manganese. Currently, there is no consistency regarding serum trace element levels in schizophrenic patients. Thus, it cannot be considered as a reliable prognostic or diagnostic marker of schizophrenia. However, it can be assumed that altered concentrations of those elements are crucial regarding the onset and exaggeration of either psychotic or negative symptoms or cognitive dysfunctions.

Nutrition, growth, and other factors associated with early cognitive and motor development in Sub-Saharan Africa: a scoping review

BACKGROUND

Food insecurity, poverty and exposure to infectious disease are well-established drivers of malnutrition in children in Sub-Saharan Africa. Early development of cognitive and motor skills - the foundations for learning - may also be compromised by the same or additional factors that restrict physical growth. However, little is known about factors associated with early child development in this region, which limits the scope to intervene effectively. To address this knowledge gap, we compared studies that have examined factors associated with early cognitive and/or motor development within this population.

METHODS

Predetermined criteria were used to examine four publication databases (PsycInfo, Embase, Web of Science and Medline) and identify studies considering the determinants of cognitive and motor development in children aged 0-8 years in Sub-Saharan Africa.

RESULTS

In total, 51 quantitative studies met the inclusion criteria, reporting on 30% of countries across the region. Within these papers, factors associated with early child development were grouped into five themes: Nutrition, Growth and Anthropometry, Maternal Health, Malaria and HIV, and Household. Food security and dietary diversity were associated with positive developmental outcomes, whereas exposure to HIV, malaria, poor maternal mental health, poor sanitation, maternal alcohol abuse and stunting were indicators of poor cognitive and motor development.

DISCUSSION

In this synthesis of research findings obtained across Sub-Saharan Africa, factors that restrict physical growth are also shown to hinder the development of early cognitive and motor skills, although additional factors also influence early developmental outcomes. The study also reviews the methodological limitations of conducting research using Western methods in sub-Saharan Africa.

The Role of Iron in Brain Development: A Systematic Review

One-third of children falter in cognitive development by pre-school age. Iron plays an important role in many neurodevelopmental processes, and animal studies suggest that iron sufficiency in pregnancy and infancy is particularly important for neurodevelopment. However, it is not clear whether iron deficiency directly impacts developmental outcomes, and, if so, whether impact differs by timing of exposure or developmental domain. We searched four databases for studies on iron deficiency or iron supplementation in pregnancy, or at 0-6 months, 6-24 months, or 2-4 years of age. All studies included neurodevelopmental assessments in infants or children up to 4 years old. We then qualitatively synthesized the literature. There was no clear relationship between iron status and developmental outcomes across any of the time windows or domains included. We identified a large quantity of low-quality studies, significant heterogeneity in study design and a lack of research focused on pregnancy and early infancy. In summary, despite good mechanistic evidence for the role of iron in brain development, evidence for the impact of iron deficiency or iron supplementation on early development is inconsistent. Further high-quality research is needed, particularly within pregnancy and early infancy, which has previously been neglected.

Association of maternal hemoglobin and iron stores with neonatal hemoglobin and iron stores

Background

One of the commonest causes of anemia in pregnancy is iron deficiency. This study aims at understanding and exploring the association between fetal and maternal iron status. Predelivery maternal hemoglobin (Hb) and iron stores, serum iron, ferritin, and soluble transferrin receptor (sTfR), were assessed and compared to the cord blood Hb and iron stores with an attempt to identify the level of maternal Hb and ferritin at which the fetal iron stores reduce, helping to identify the neonates who will require earlier iron supplementation.

Method

Four hundred eight participants were enrolled, and maternal and cord blood was collected at the time of delivery and tested for Hb and iron parameters. The results were statistically analyzed.

Results

Of all mothers, 27.2% mothers were anemic (Hb less than 11 g/dl). Of all newborns, 15.4% newborns had Hb less than 14 g/dl. There was a significant association between the maternal and cord blood iron, ferritin, sTfR and sTfR/log ferritin index. Eighty-five percent of the babies with cord blood Hb <14 g/dl had maternal serum ferritin (SF) <50 μg/L. Maternal SF <10 μg/l was associated with a significant number of babies with cord blood SF <75 μg/l (77.7%). One hundred sixty six neonates had sTfR 2 μg/ml or more. Of these, 80.7% had maternal SF <50 μg/l. Of the 115 newborns with a high sTfR/log ferritin index (>1.5), 56.5% had raised maternal sTfR (>2μg/ml).

Conclusion

In view of a significant association between maternal and neonatal Hb and iron stores, newborns of mothers with iron deficiency anemia (IDA) during pregnancy should be monitored and followed up after birth for development of IDA and early iron supplementation.

The impact of common mental disorders among caregivers living with HIV on child cognitive development in Zimbabwe

This paper aimed to assess the impact of maternal common mental disorders (CMD) among caregivers living with HIV on the cognitive functioning of their child. Data were collected at baseline and 12 months follow-up from mother-child dyads recruited as part of an ongoing trial in Zimbabwe. Symptoms of CMD were assessed using the Shona Symptom Questionnaire. Mixed-effects linear regression was used to assess child cognitive scores at follow-up (using the Mullen Scales of Early Learning) in relation to caregiver CMD prevalence over 12 months. At baseline, caregivers reporting CMD (n = 230; 40.1%) were less likely to have completed higher education (46.9% vs. 56.9%; p = 0.02), more likely to be unmarried (27.8% vs. 16.0%; p < 0.01), and experience food insecurity (50.0% vs. 29.4%; p < 0.01) compared to the group without CMD (n = 344). There were 4 CMD patterns over time: (i) Emerging CMD (n = 101; 19.7% of caregivers) defined as those who were below the cut-off at baseline, and above it at 12 months; (ii) Improving CMD (n = 76; 14.8%) defined as those who reported CMD at baseline, and were below the cut-off by follow-up; (iii) No CMD (n = 206; 40.1%) defined as those who did not report CMD symptoms at either time point; and (iv) Chronic CMD (n = 131; 25.5%) defined as those who reported CMD above the cut-off at both time points. Children of caregivers with chronic CMD (n = 131, 25.5%) had lower receptive language scores (aMD:-2.81, 95%CI -5.1 to -0.6; p = 0.05) compared to the reference group with no CMD (n = 206, 40.1%). Exposure to caregiver CMD over a prolonged period may affect child receptive vocabulary skills.

Impairment of the Developing Human Brain in Iron Deficiency: Correlations to Findings in Experimental Animals and Prospects for Early Intervention Therapy

Due to the necessity of iron for a variety of cellular functions, the developing mammalian organism is vulnerable to iron deficiency, hence causing structural abnormalities and physiological malfunctioning in organs, which are particularly dependent on adequate iron stores, such as the brain. In early embryonic life, iron is already needed for proper development of the brain with the proliferation, migration, and differentiation of neuro-progenitor cells. This is underpinned by the widespread expression of transferrin receptors in the developing brain, which, in later life, is restricted to cells of the blood–brain and blood–cerebrospinal fluid barriers and neuronal cells, hence ensuring a sustained iron supply to the brain, even in the fully developed brain. In embryonic human life, iron deficiency is thought to result in a lower brain weight, with the impaired formation of myelin. Studies of fully developed infants that have experienced iron deficiency during development reveal the chronic and irreversible impairment of cognitive, memory, and motor skills, indicating widespread effects on the human brain. This review highlights the major findings of recent decades on the effects of gestational and lactational iron deficiency on the developing human brain. The findings are correlated to findings of experimental animals ranging from rodents to domestic pigs and non-human primates. The results point towards significant effects of iron deficiency on the developing brain. Evidence would be stronger with more studies addressing the human brain in real-time and the development of blood biomarkers of cerebral disturbance in iron deficiency. Cerebral iron deficiency is expected to be curable with iron substitution therapy, as the brain, privileged by the cerebral vascular transferrin receptor expression, is expected to facilitate iron extraction from the circulation and enable transport further into the brain.

A systematic literature review of the relation between iron status/anemia in pregnancy and offspring neurodevelopment

BACKGROUND

The fetal brain starts developing early and animal studies have suggested that iron plays several roles for the development, but results from epidemiological studies investigating associations between gestational iron and offspring neurodevelopment are inconsistent.

OBJECTIVE

To systematically examine results from observational studies and RCTs on gestational iron and offspring neurodevelopment, with focus on the importance of four domains: iron status indicators, exposure timing, neurodevelopmental outcomes, and offspring age.

METHODS

PRISMA guidelines were followed. Embase, PsychInfo, Scopus, and The Cochrane library were searched in September 2017 and February 2018. Overall, 3307 articles were identified and 108 retrieved for full-text assessment. Pre-specified eligibility criteria were used to select studies and 27 articles were included;19 observational and 8 RCTs.

RESULTS

Iron status in pregnancy was associated with offspring behavior, cognition, and academic achievement. The direction of associations with behavioral outcomes were unclear and the conclusions related to cognition and academic achievement were based on few studies, only. Little evidence was found for associations with motor development. Observed associations were shown to persist beyond infancy into adolescence, and results depended on iron status indicator type but not on the timing of exposure.

CONCLUSION

We conclude that there is some evidence that low pregnancy iron, possibly particularly in the 3rd trimester, may be associated with adverse offspring neurodevelopment. As most previous research used Hemoglobin, inferring results to iron deficiency should be done with caution. No conclusions could be reached regarding associations beyond early childhood, and supplementation with iron during pregnancy did not seem to influence offspring neurodevelopment.

Concurrent exposure to heavy metals and cognition in school-age children in Congo-Kinshasa: A complex overdue research agenda

The impact of concurrent exposure to neurotoxic metals is a significant threat to brain function, mostly in contexts of multiple exposures as seen in the developing world. Ninety-five children (46 boys and 49 girls, 6 to 11-year old) from Congo-Kinshasa were assessed for cognition using the Kaufman Assessment Battery for Children (2nd edition) and exposure to Cr, Cu, Zn, Co, Mn, As, Cd, Se, Hg, Fe, and Pb by inductively coupled plasma mass spectrometry (ICPMS) in serum and urine collections. Concentrations of elements were all above normal ranges except for Cd, Se and Hg. General linear mixed effects models were used to predict neurocognitive outcomes with variable selection methods including backward elimination, elastic net, or subsets identified based on subject matter expertise. After adjusting for sex, age, and SES, urinary Co > 5 μg/l was associated with poor simultaneous processing (memory) (p = 0.0237). Higher excretion but normal concentration of Cd in serum was associated with better memory (p = 0.03), planning (p = 0.05), and overall performance scores (p < 0.01); thus appeared to be neuroprotective. However, higher excretion of Zn had negative influence on the overall performance scores (p = 0.02). Predictive neurotoxicology is a challenging task in contexts of multiple and concurrent exposures. Urinary Co > 5 μg/l is a risk factor for poor neurodevelopmental outcomes in such contexts. The impact of heavy metals on cognition is dependent on concentrations of and interactions between toxic and essential elements.

Postpartum maternal mental health is associated with cognitive development of HIV-exposed infants in Zimbabwe: a cross-sectional study

This study examines the cognitive profiles of infants born to HIV positive mothers in Zimbabwe. Caregivers with HIV exposed infants delivered in 30 clinics in two areas of Zimbabwe were recruited to the study. Of the 574 study participants, 562 caregiver-infant dyads with a biological HIV +ve mother and infant aged 0-24 months were interviewed. All infants were tested by a trained administrator for cognitive development on the Mullen Scales of Early Learning (MSEL). The Edinburgh Postnatal Depression Scale and Parental Stress Index-Short Form were completed by the mothers together with infant and caregiver socioeconomic characteristics. Linear regression models were used to relate cognitive development scores to maternal stress scores, maternal depression scores and infant HIV status adjusting for infant and caregiver characteristics, as well as socioeconomic factors. Higher maternal depression scores were associated with lower overall infant cognitive scores (adjusted mean difference (aMD) = -0.28; CI 95%:-0.50 to -0.06; p = 0.01) and in the expressive language (aMD = -0.14; CI 95%:-0.27 to -0.01; p = 0.04), fine motor skills (aMD = -0.17; CI 95%: -0.33 to -0.01; p = 0.03), gross motor (aMD = -0.22; CI 95%:-0.40 to -0.04; p = 0.02), and visual reception (aMD = -0.22; CI 95%:-0.40 to -0.05; p = 0.01) domains. Higher maternal stress was associated with poorer overall infant cognitive scores (aMD = -0.11; CI 95%:-0.20 to -0.02; p = 0.02) and in the specific domains of expressive language (aMD = -0.07; CI 95%:-0.12 to -0.01; p = 0.01), gross motor skills (aMD = -0.12; CI 95%:-0.18 to -0.05; p < 0.01) and visual reception (aMD = -0.09; CI 95%:-0.16 to -0.02; p = 0.02). Comparisons between the small number of HIV positive infants (n = 16) and the HEU infants (n = 381) showed the latter to have higher mean gross motor scores (50.3 vs. 40.6; p = 0.01). There was no evidence of difference by HIV status in the other MSEL domains or overall mean cognitive scores. Our findings demonstrate the association between maternal mood and stress levels and child cognitive functioning, particularly in expressive language and visual reception development. Although cross sectional data cannot shed light on the direction of this association, the study suggests that interventions to address maternal stress and depression symptoms may prove to be beneficial.

Redefining normal hemoglobin and anemia in singleton and twin pregnancies

OBJECTIVE

To assess the benefit of a hemoglobin cutoff of 105 g/L as a trigger for anemia evaluation during the second trimester of pregnancy.

METHODS

The present cross-sectional study, conducted at a health center in Israel between January 1, 2010, and December 31, 2015, included pregnant women with hemoglobin values below 105 g/L who were assessed for anemia. Anemia workup included complete blood count, serum ferritin and vitamin B12 measurements, and hemoglobin electrophoresis. The primary outcome was the incidence of nondilutional anemia, defined by a positive workup, across predefined hemoglobin thresholds. Receiver operating characteristic curves were created to identify the best hemoglobin threshold for predicting anemia, mandating further evaluation.

RESULTS

In total, 651 women with singleton and 300 women with twin pregnancies were evaluated for nondilutional anemia. Of these, 340 (52.2%) and 127 (42.3%) women, respectively, had positive workup results. The most common cause was iron deficiency. The hemoglobin values that best predicted positive workup results were 100 g/L in singleton pregnancies and 97 g/L in twin pregnancies.

CONCLUSION

Anemia evaluation could be unnecessary in pregnant women with a hemoglobin value of 100-105 g/L. Consideration should be given to redefining anemia in singleton and twin pregnancies.

Neurological effects of iron supplementation in infancy: finding the balance between health and harm in iron-replete infants

Iron mediates many biochemical processes in neural networks that proliferate during brain development. Insufficient iron causes irreversible neurodevelopmental deficits, and most high-income countries recommend that infants older than 4-6 months receive additional iron via food fortification or supplementation to prevent iron-deficiency anaemia. Now that the prevalence of iron-deficiency anaemia in children has decreased to less than 10% in most developed countries, concerns that the recommended intakes far exceed those required to prevent iron-deficiency anaemia have been raised, and emerging evidence suggests that iron overexposure could be linked to adverse outcomes later in life. In this Viewpoint, we discuss the importance of iron for neurodevelopment, investigate the biochemical markers used to assess iron stores, summarise the disparity in public health policies among high-income countries, and discuss the potential association between iron overexposure and adverse neurological outcomes later in life. We present a case for new studies to establish the optimal amount of iron that both prevents deficiency and reduces the potential risk of long-term negative health outcomes.