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

Concordance between Hemoglobin and Hematocrit among Children and Pregnant Persons in National Health and Nutrition Examination Survey Data, 1999-2020

BACKGROUND

Hemoglobin and hematocrit are the 2 most common biomarkers used to identify anemia in clinical settings, but their results do not always agree.

OBJECTIVES

To examine agreement between hemoglobin and hematocrit in identifying anemia among children aged 1 to <5 y and pregnant persons.

METHODS

Pregnant persons and children aged 1 to <5 y with hemoglobin and hematocrit results from the same whole blood sample in National Health and Nutrition Examination Survey (1999-2020) were included. We used the Centers for Disease Control and Prevention anemia cutoff values for children, pregnancy status, trimester, and smoking adjustments. We examined concordance of anemia, sensitivity, and specificity among those with anemia based on ≥1 test overall and by race/ethnicity, sex, and income level. Cohen's kappa was used to measure concordance.

RESULTS

Analytic samples included 7052 children and 1437 pregnant persons, of whom 1119 had trimester data. Among children, anemia prevalence was 3.7% [95% confidence interval (CI): 3.1, 4.3] based on hemoglobin and 5.5% (95% CI: 4.7, 6.3) based on hematocrit. Among pregnant persons, anemia prevalence was 7.7% (95% CI: 5.9, 9.5) based on hemoglobin and 12.4% (95% CI: 10.1, 14.6) based on hematocrit. Kappa scores overall and by sociodemographic characteristics ranged from 0.64 to 0.75 (moderate concordance) among children and from 0.53 to 0.78 (weak to moderate concordance) among pregnant persons. Among those with anemia on ≥1 test, 53.5% of children and 61.5% of pregnant persons had anemia based on both tests.

CONCLUSIONS

We found substantial discordance between the 2 biomarkers; ∼50% of children and 40% of pregnant women were identified by only 1 of the 2 biomarkers. Because hemoglobin and hematocrit may be used interchangeably in the clinical setting, individuals with anemia may be missed, not receive treatment, and therefore be at higher risk of adverse pregnancy, birth, and developmental outcomes.

Change in the prevalence of anemia in children aged 6-59 months using the new World Health Organization 2024 criteria

The World Health Organization (WHO) has published new hemoglobin cutoff points for defining anemia and its measurement. This change could impact the prevalence of anemia, particularly in countries with populations living in high-altitude areas. This study estimates the national prevalences of anemia in children aged 6-59 months using Centers for Disease Control and Prevention (CDC) 1989 and WHO 2024 criteria. Data from 406,106 children in 48 countries (45 Demographic and Health Surveys [DHS Program] and 3 Andean [Ecuador, Bolivia, and Peru]) were analyzed. The pooled prevalence of anemia was 61.4% according to the WHO 2024 criteria. Three countries showed changes in anemia prevalence, with shifts of 10 or more percentage points (Uganda, Rwanda, and Jordan). Across all the studied countries, the prevalence of anemia was higher at greater altitudes, rural areas, and children from households of low wealth quintiles, regardless of the criteria used. Moreover, changes in anemia prevalence were identified when stratified by altitude of residence, showing differences in the levels of public health significance across various political-administrative regions in Andean countries. Overall, these findings provide valuable insights into the epidemiology of anemia and highlight the need for continued surveillance and targeted interventions to effectively address this global health challenge.

The Effects of Prenatal Iron Supplementation on Offspring Neurodevelopment in Upper Middle- or High-Income Countries: A Systematic Review

Iron supplementation is commonly recommended for the prevention and treatment of maternal iron deficiency (ID) or iron deficiency anemia (IDA). However, the impacts of prophylactic of therapeutic prenatal iron supplementation on child neurodevelopment in upper middle-income (UMI) and high-income countries (HICs), where broad nutritional deficiencies are less common, are unclear. To investigate this, we conducted a systematic review, searching four databases (Medline, CINAHL, EMBASE, Cochrane Library) through 1 May 2023. Randomized controlled trials (RCTs) assessing oral or intravenous iron supplementation in pregnant women reporting on child neurodevelopment (primary outcome: age-standardized cognitive scores) were eligible. We included three RCTs (five publications) from two HICs (Spain and Australia) (N = 935 children; N = 1397 mothers). Due to clinical heterogeneity of the RCTs, meta-analyses were not appropriate; findings were narratively synthesized. In non-anemic pregnant women, prenatal iron for prevention of IDA resulted in little to no difference in cognition at 40 days post-partum (1 RCT, 503 infants; very low certainty evidence). Similarly, the effect on the intelligence quotient at four years was very uncertain (2 RCTs, 509 children, very low certainty evidence). No RCTs for treatment of ID assessed offspring cognition. The effects on secondary outcomes related to language and motor development, or other measures of cognitive function, were unclear, except for one prevention-focused RCT (302 children), which reported possible harm for children's behavioral and emotional functioning at four years. There is no evidence from UMI countries and insufficient evidence from HICs to support or refute benefits or harms of prophylactic or therapeutic prenatal iron supplementation on child neurodevelopment.

Biomarkers of Brain Dysfunction in Perinatal Iron Deficiency

Iron deficiency in the fetal and neonatal period (perinatal iron deficiency) bodes poorly for neurodevelopment. Given its common occurrence and the negative impact on brain development, a screening and treatment strategy that is focused on optimizing brain development in perinatal iron deficiency is necessary. Pediatric societies currently recommend a universal iron supplementation strategy for full-term and preterm infants that does not consider individual variation in body iron status and thus could lead to undertreatment or overtreatment. Moreover, the focus is on hematological normalcy and not optimal brain development. Several serum iron indices and hematological parameters in the perinatal period are associated with a risk of abnormal neurodevelopment, suggesting their potential use as biomarkers for screening and monitoring treatment in infants at risk for perinatal iron deficiency. A biomarker-based screening and treatment strategy that is focused on optimizing brain development will likely improve outcomes in perinatal iron deficiency.

Prenatal iron supplementation adjusted to maternal iron stores reduces behavioural problems in 4-year-old children

Prenatal iron supplementation improves children's health and cognitive performance, but few studies explore behavioural development. This study assessed the effects of adjusting prenatal iron supplementation to maternal iron stores during early pregnancy on children's behavioural problems. Randomized controlled trial conducted in Tarragona (Spain) involving 230 nonanaemic pregnant women and their children after a 4-year follow-up. Based on haemoglobin (Hb) levels before gestational week (GW) 12, women receive different iron doses: those with Hb = 110-130 g/L were randomized to receive 80 or 40 mg/day and those with Hb > 130 g/L were randomized to receive 20 or 40 mg/day. Maternal iron stores at GW12 were classified using serum ferritin (SF) as low (SF < 15 µg/L), normal (SF = 15-65 µg/L), and normal-high (SF > 65 µg/L). Children's behaviour was assessed by parents using the Child Behaviour Checklist for ages 1.5-5 years and the Behaviour Rating Inventory of Executive Function-Preschool Version, and by teachers using the Teacher's Report Form for ages 1.5-5 years. Multivariable regression models were performed. Taking 80 mg/day of iron improved child behaviour when women had low iron stores but worsened it when mothers had normal-high iron stores, except for depressive and attention/hyperactivity problems. Taking 20 mg/day of iron improved behaviour only in those children whose mothers had SF > 65 µg/L in early pregnancy. Additionally, executive functioning improved at high doses of prenatal iron when maternal baseline SF < 15 µg/L. Adjusting prenatal iron supplementation to both maternal baseline Hb levels and iron stores reduces behavioural problems in 4-year-old children.

RAPIDIRON Trial follow-up study - the RAPIDIRON-KIDS Study: protocol of a prospective observational follow-up study

BACKGROUND

Anemia is a worldwide problem with iron deficiency being the most common cause. When anemia occurs in pregnancy, it increases the risk of adverse maternal, fetal, and postnatal outcomes. It induces preterm births and low birth weight (LBW) deliveries, long-term neurodevelopmental sequelae, and an increased risk of earlier onset of postnatal iron deficiency. Anemia rates are among the highest in South Asia, and India's National Family Health Survey (NFHS-5) for 2019-2021 indicated that over half of pregnant women, and more than 65% of children, in the country are classified as anemic (Sciences IIfP, National Family Health Survey-5, 2019-21, India Fact Sheet). In 2021, the parent RAPIDIRON Trial (Derman et al., Trials 22:649, 2021) was initiated in two states in India, with the goal of assessing whether a dose of intravenous (IV) iron given to anemic women during early pregnancy results in a greater proportion of participants with normal hemoglobin concentrations in the third trimester and a lower proportion of participants with LBW deliveries compared to oral iron. As a follow-up to the RAPIDIRON Trial, the RAPIDIRON-KIDS Study will follow the offspring of previously randomized mothers to assess, neurobehavioral, hematological, and health outcomes.

METHODS

This prospective observational cohort study will follow a subset of participants previously randomized as part of the RAPIDIRON Trial and their newborns. Study visits occur at birth, 6 weeks, 4 months, 12 months, 24 months, and 36 months and include blood sample collection with both maternal and infant participants and specific neurobehavioral assessments conducted with the infants (depending on the study visit). The primary outcomes of interest are (1) infant iron status as indicated by both hemoglobin and ferritin (a) at birth and (b) at 4 months of age and (2) the developmental quotient (DQ) for the cognitive domain of the Bayley Scales of Infant Development Version IV (BSID-IV) at 24 months of age.

DISCUSSION

This RAPIDIRON-KIDS Study builds upon its parent RAPIDIRON Trial by following a subset of the previously randomized participants and their offspring through the first 3 years of life to assess neurodevelopmental and neurobehavioral (infants, children), hematological, and health outcomes.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05504863 , Registered on 17 August 2022. Clinical Trials Registry - India CTRI/2022/05/042933 . Registered on 31 May 2022.

Anemia, Iron Supplementation, and the Brain

The developing brain is particularly vulnerable to extrinsic environmental events such as anemia and iron deficiency during periods of rapid development. Studies of infants with postnatal iron deficiency and iron deficiency anemia clearly demonstrated negative effects on short-term and long-term brain development and function. Randomized interventional trials studied erythropoiesis-stimulating agents and hemoglobin-based red blood cell transfusion thresholds to determine how they affect preterm infant neurodevelopment. Studies of red blood cell transfusion components are limited in preterm neonates. A biomarker strategy measuring brain iron status and health in the preanemic period is desirable to evaluate treatment options and brain response.

Maternal gestational iron status and infant haematological and neurodevelopmental outcomes

Prevention of iron deficiency (ID), the most common micronutrient deficiency in infants and children, begins prenatally by ensuring adequate fetal loading. Adequate intrauterine iron status is crucial for normal fetal brain development, postnatal brain performance and prevention of early postnatal iron deficiency, particularly in infants fed exclusively human milk. Adequate fetal loading may be achieved in some cases through adequate maternal iron levels prior to pregnancy and oral iron supplementation during pregnancy. However, because so many women are iron-deficient leading up to pregnancy, coupled with the negative iron balance induced by pregnancy, a large number of women remain iron-deficient during pregnancy. More consistent iron-specific early screening and more effective iron delivery approaches are needed to solve this global problem.

ASQ-3 and BSID-III's concurrent validity and predictive ability of cognitive outcome at 5 years

BACKGROUND

Early detection of cognitive disability is challenging. We assessed the domain-specific, concurrent validity of the ages and stages questionnaire (ASQ-3) and the Bayley Scales of Infant and Toddler Development (BSID-III), and their ability to predict cognitive delay at school age.

METHODS

Within a longitudinal birth cohort study, a nested cohort of children was assessed using ASQ-3 and BSID-III at 24 months, and at 5 years using the Kaufmann brief IQ test (KBIT).

RESULTS

278 children were assessed using BSID-III and ASQ-3 at 24-months; mean(SD) BW = 3445(506) grams, M:F ratio=52:48. ASQ-3 had reasonable predictive ability (AUROC, p value, sensitivity:specificity) of same domain delay for motor (0.630, p = 0.008, 50%:76.1%) and language (0.623, p = 0.010, 25%:99.5%) at 2 years, but poor ability to detect cognitive delay compared to BSID-III (0.587, p = 0.124, 20.7%/96.8%;). 204/278 children were assessed at 5 years. BSID-III language and cognition domains showed better correlation with verbal and nonverbal IQ (R = 0.435, p < 0.001 and 0.388, p < 0.001 respectively). Both assessments showed high specificity and low sensitivity for predicting delay at 5 years.

CONCLUSIONS

The ASQ-3 cognitive domain showed poor concurrent validity with BSID-III cognitive score. Both ASQ-3 and BSID-III at 2 years poorly predict cognitive delay at 5 years.

IMPACT

The ASQ-3 does not adequately detect cognitive delay or predict cognitive delay at 5 years, particularly for children with mild to moderate delay. The ASQ-3 shows reasonable concurrent validity with the motor and language subscales of the BSID-III. Neither early screening nor formal developmental testing demonstrated significant predictive validity to screen for cognitive delay at school age. This article highlights the need to analyse our existing model of using the ASQ-3 to screen for cognitive delay in children aged 2 years.

The Prevalence of Anemia in Children Aged 6-23 Months and its Correlates Differ by District in Kapilvastu and Achham Districts in Nepal

Background

Analyses of predictors of anemia or malnutrition often pool national or regional data, which may hide variability at subnational levels.

Objectives

We sought to identify the risk factors for anemia in young Nepali children aged 6-23 mo in 2 districts: Kapilvastu and Achham.

Methods

This is an analysis of two cross-sectional surveys that were conducted as part of a program evaluation of an infant and young child feeding and micronutrient powder intervention that included anemia as a primary outcome. Baseline and endline surveys in each district (in 2013 and 2016) included hemoglobin assessments in n = 4709 children who were representative of children 6-23 mo in each district. Log-binomial regression models accounting for the survey design were used to estimate univariable and multivariable prevalence ratios for risk factors at multiple levels-underlying, direct, and biological causes. Average attributable fractions (AFs) for the population were calculated for significant predictor biomarkers of anemia in multivariable models.

Results

In Accham, the prevalence of anemia was 31.4%; significant predictors included child's age, household asset ownership, length-for-age z-score, inflammation (CRP concentration > 0.5 mg/L; α-1 acid glycoprotein concentration > 1 mg/mL), and iron deficiency (serum ferritin concentration < 12 μg/L with BRINDA-inflammation adjustment). In Kapilvastu, the prevalence of anemia was 48.1%; significant predictors included child's sex and ethnicity, wasting and weight-for-length z-score, any morbidity in the previous 2 wk, consumption of fortified foods, receipt of multiple micronutrient powder distributions, iron deficiency, zinc deficiency (nonfasting serum zinc concentration of <65 μg/dL in the morning and that of <57 μg/dL in the afternoon), and inflammation. In Achham, average AFs were 28.2% and 19.8% for iron deficiency and inflammation, respectively. Average AFs for anemia in Kapilvastu were 32.1%, 4.2%, and 4.9% for iron deficiency, zinc deficiency, and inflammation, respectively.

Conclusions

The prevalence of anemia and its risk factors varied between districts, with inflammation contributing to a greater share of anemia in Achham than in Kapilvastu. The estimated AF for iron deficiency was around 30% in both districts; iron-delivering interventions and multisectoral approaches to anemia are warranted.

Effects of antenatal micronutrient supplementation regimens on adolescent emotional and behavioral problems: A 14-year follow-up of a double-blind, cluster-randomized controlled trial

BACKGROUND & AIMS

Antenatal multiple micronutrient supplementation has been shown to have beneficial effects on birth outcomes and may improve child development. However, whether there is an effect of antenatal micronutrient supplementation strategies on offspring socioemotional outcomes remains unknown. We aimed to examine the effect of antenatal folic acid (FA), iron-folic acid (IFA), and multiple micronutrient (MMN) supplementation on adolescent emotional and behavioral outcomes.

METHODS

We conducted a double-blind, cluster-randomized trial of antenatal micronutrient supplementation in rural western China between 2002 and 2006. Pregnant females were randomized by village to receive either daily (i) 400 μg FA, (ii) IFA containing 60 mg iron and 400 μg FA or (iii) MMN supplementation containing 30 mg iron, 400 μg FA plus 13 additional vitamins and minerals. A 14-year follow-up of their offspring was conducted in 2016. Adolescents were administered the locally adapted Youth Self-Report-2001 (YSR-2001) which produced internalizing, externalizing, and total behavior problem scores. We applied generalized estimating equations to assess the effect of the randomized regimens on YSR-2001 scores and explored the potential effect modification by household wealth and initial timing and duration of supplementation.

RESULTS

A total of 1920 adolescents were included in the analysis, 1130 (58.9%) were male, and the mean (SD) age was 11.8 (0.78) years. Adolescents in IFA group had lower total (mean difference (MD): -2.89; 95% CI -5.73, -0.04) and externalizing (MD: -0.97; 95% CI -1.79, -0.15) problem scores as compared to those in FA group. There was no effect of MMN on behavior problem scores as compared to IFA and FA alone. Although, in effect modification analyses, MMN appeared to have greater beneficial effects in wealthier households than IFA and FA alone.

CONCLUSIONS

Iron supplementation during pregnancy reduced adolescent emotional and behavioral problem scores which provides additional support for expanding coverage of iron-containing prenatal supplements in resource-limited settings.

TRIAL REGISTRATION

isrctn. org Identifier: ISRCTN08850194.

Reference range of complete blood count, Ret-He, immature reticulocyte fraction, reticulocyte production index in healthy babies aged 1-4 months

Establishing reference ranges of the complete blood count (CBC), reticulocyte hemoglobin content (Ret-He), immature reticulocyte fraction (IRF), and reticulocyte production index (RPI) helps diagnose a disease related to the changes in erythrocyte indices, white blood count, platelets, and reticulocytes, especially in babies. Therefore, the study aims to establish a reference range for CBC and reticulocyte parameters in healthy babies aged 1-4 months. The study design was a cross-sectional study with descriptive analysis of CBC and reticulocyte in babies aged 1-4 months. Three hundred forty-eight babies met the inclusion criteria. This study recruited 89 babies aged 1 month, 87 babies aged 2 months, 86 babies aged 3 months, and 86 babies aged 4 months. The P5-P95 reference range of healthy babies for hemoglobin (Hb) aged 1 month, 2 months, 3 months, and 4 months was 9.95 to 15.45 g/dL, 9.74 to 13.42 g/dL, 9.51 to 12.40 g/dL, and 10.04 to 13.10 g/dL respectively. The P3-P97 reference range of healthy babies for Hb aged 1 month, 2 months, 3 months, and 4 months was 9.60 to 15.90 g/dL, 9.46 to 13.97 g/dL, 9.26 to 12.82 g/dL, and 10.00 to 13.33 g/dL respectively. This study also defined reference ranges for CBC, Ret-He, IRF, and RPI. The reference range of CBC, Ret-He, IRF, and RPI for healthy babies aged 1-4 months in this study can be used as a benchmark.

Iron Deficiency in the United States: Limitations in Guidelines, Data, and Monitoring of Disparities

Iron deficiency and the more severe sequela, iron deficiency anemia, are public health problems associated with morbidity and mortality, particularly among pregnant women and younger children. The 1998 Centers for Disease Control and Prevention recommendations for prevention and control of iron deficiency in the United States is old and does not reflect recent evidence but is a foundational reference for many federal, clinical, and program guidelines. Surveillance data for iron deficiency are sparse at all levels, with critical gaps for pregnant women and younger children. Anemia, iron deficiency, and iron deficiency anemia are often conflated but should not be. Clinical guidelines for anemia, iron deficiency, and iron deficiency anemia give inconsistent recommendations, causing nonsystematic assessment of iron deficiency. Screening for iron deficiency typically relies on identifying anemia, despite anemia's low sensitivity for iron deficiency. In the National Health and Nutrition Examination Survey, more than 70% of iron deficiency is missed among pregnant women and children by relying on hemoglobin for iron deficiency screening. To improve assessment and diagnosis and strengthen surveillance, better and more complete data and updated foundational guidance on iron deficiency and anemia are needed that consider new evidence for measuring and interpreting laboratory results. (Am J Public Health. 2022;112(S8):S826-S835. https://doi.org/10.2105/AJPH.2022.306998).

Iron deficiency during the first 1000 days of life: are we doing enough to protect the developing brain?

Iron is essential for the functioning of all cells and organs, most critically for the developing brain in the fundamental neuronal processes of myelination, energy and neurotransmitter metabolism. Iron deficiency, especially in the first 1000 days of life, can result in long-lasting, irreversible deficits in cognition, motor function and behaviour. Pregnant women, infants and young children are most vulnerable to iron deficiency, due to their high requirements to support growth and development, coupled with a frequently inadequate dietary supply. An unrecognised problem is that even if iron intake is adequate, common pregnancy-related and lifestyle factors can affect maternal-fetal iron supply in utero, resulting in an increased risk of deficiency for the mother and her fetus. Although preterm birth, gestational diabetes mellitus and intrauterine growth restriction are known risk factors, more recent evidence suggests that maternal obesity and delivery by caesarean section further increase the risk of iron deficiency in the newborn infant, which can persist into early childhood. Despite the considerable threat that early-life iron deficiency poses to long-term neurological development, life chances and a country's overall social and economic progress, strategies to tackle the issue are non-existent, too limited or totally inappropriate. Prevention strategies, focused on improving the health and nutritional status of women of reproductive age are required. Delayed cord clamping should be considered a priority. Better screening strategies to enable the early detection of iron deficiency during pregnancy and early-life should be prioritised, with intervention strategies to protect maternal health and the developing brain.

Iron, iodine and vitamin D deficiencies during pregnancy: epidemiology, risk factors and developmental impacts

Micronutrient deficiency persists throughout the world, and although the burden is higher in low-resource settings, it is also prevalent in wealthy countries, a phenomenon termed 'hidden hunger'. Due to their high requirements for vitamins and minerals relative to their energy intake, young women and children are particularly vulnerable to hidden hunger. As they share several risk factors and impact on overlapping outcomes, we consider how deficiency of iron, iodine and vitamin D can have profound impacts on perinatal health and infant development. We review the epidemiology of these micronutrient deficiencies during pregnancy, including social, environmental and dietary risk factors. We identify the main challenges in defining nutritional status of these nutrients using validated diagnostic criteria linked with meaningful clinical outcomes. Public health strategies are urgently required to improve the overall health and nutritional status of women of reproductive age. Obesity prevention and early detection of malnutrition with standardised screening methods would detect pregnant women at increased risk of iron deficiency. Development of sensitive, individual biomarkers of iodine status is required to protect maternal health and fetal/infant brain development. Risk assessments of vitamin D requirements during pregnancy need to be revisited from the perspective of fetal and neonatal requirements. International consensus on standardised approaches to micronutrient assessment, analysis and reporting as well as sensitive, clinically validated infant and child neuro-behavioural outcomes will enable progression of useful observational and intervention studies.