Iron deficiency in young children in low-income countries and new approaches for its prevention

Short-term evaluation of the impact of a food program on the micronutrient nutritional status of Argentinean children under the age of six

This study was undertaken to evaluate the impact of Plan Más Vida (PMV) on the micronutrient nutritional condition of children aged 1 to 6 years 1 year after PMV implementation. The food program was intended for low-income families from the province of Buenos Aires, Argentina and provided supplementary diets. A prospective, nonexperimental study was carried out. Children (472 at baseline and 474 after 1 year) were divided into two groups (1-2 and 2-6 years of age). Biochemical tests (hemogram, ferritin, zinc, vitamin A, and folic acid), anthropometric assessments (weight and height), and dietary surveys (24-h recall) were performed. Chronic growth retardation (-2 height/age Z-score) was present in 2.8% and 8.7% of 1-2- and 2-6-year-old children, respectively; 14.4% in the former and 8.8% in the latter group had overweight/obesity. No significant changes were recorded 1 year after PMV implementation. Whereas anemia values decreased (55.3% to 39.1%, p = 0.003) and serum zinc values increased in 1-2-year-old children, the risk for vitamin A deficiency decreased significantly in both age groups. The evaluation of the early impact of PMV actions provided important nutritional data that should be used by provincial health authorities to conduct future evaluations.

Air pollution and anemia as risk factors for pneumonia in Ecuadorian children: a retrospective cohort analysis

BACKGROUND

Ambient air pollution and malnutrition, particularly anemia, are risk factors for pneumonia, a leading cause of death in children under five. We simultaneously assessed these risk factors in Quito, Ecuador.

METHODS

In 2005, we studied two socioeconomically similar neighborhoods in Quito: Lucha de los Pobres (LP) and Jaime Roldos (JR). LP had relatively high levels of air pollution (annual median PM2.5 = 20.4 μg/m3; NO2 = 29.5 μg/m3) compared to JR (annual median PM2.5 = 15.3 μg/m3; NO2 = 16.6 μg/m3). We enrolled 408 children from LP (more polluted) and 413 children from JR (less polluted). All subjects were aged 18-42 months. We obtained medical histories of prior physician visits and hospitalizations during the previous year, anthropometric nutrition data, hemoglobin levels, and hemoglobin oxygen saturation via oximetry.

RESULTS

In anemic children, higher pollution exposure was significantly associated with pneumonia hospitalization (OR = 6.82, 95%CI = 1.45-32.00; P = 0.015). In non-anemic children, no difference in hospitalizations by pollution exposure status was detected (OR = 1.04, NS). Children exposed to higher levels of air pollution had more pneumonia hospitalizations (OR = 3.68, 1.09-12.44; P = 0.036), total respiratory illness (OR = 2.93, 95% CI 1.92-4.47; P < 0.001), stunting (OR = 1.88, 1.36-2.60; P < 0.001) and anemia (OR = 1.45, 1.09-1.93; P = 0.013) compared to children exposed to lower levels of air pollution. Also, children exposed to higher levels of air pollution had significantly lower oxygen saturation (92.2% ± 2.6% vs. 95.8% ± 2.2%; P < 0.0001), consistent with air pollution related dyshemoglobinemia.

CONCLUSIONS

Ambient air pollution is associated with rates of hospitalization for pneumonia and with physician's consultations for acute respiratory infections. Anemia may interact with air pollution to increase pneumonia hospitalizations. If confirmed in larger studies, improving nutrition-related anemia, as well as decreasing the levels of air pollution in Quito, may reduce pneumonia incidence.

Why nutritional iron deficiency persists as a worldwide problem

The earliest studies of food iron absorption employing biosynthetically incorporated radioisotopes were published in the 1950s. Wheat flour has been fortified with iron in Canada, the United Kingdom, and the United States since the 1940s. However, half a century later, nutritional iron deficiency (ID) is estimated to affect 1.5-2 billion people worldwide. The reasons for the apparently limited impact of health and nutrition policies aimed at reducing the prevalence of ID in developing countries are complex. They include uncertainty about the actual prevalence of ID, particularly in regions where malaria and other infections are endemic, failure of policy makers to recognize the relationships between ID and both impaired productivity and increased morbidity, concerns about safety and the risks to iron-sufficient individuals if mass fortification is introduced, and technical obstacles that make it difficult to add bioavailable iron to the diets of those at greatest risk. It is, however, likely that the next decade will see a marked reduction in the prevalence of ID worldwide. More specific assessment tools are being standardized and applied to population surveys. The importance of preventing ID during critical periods of the life cycle is receiving increased attention. Innovative approaches to the delivery of bioavailable iron have been shown to be efficacious. The importance of integrating strategies to improve iron nutrition with other health measures, and economic and social policies addressing poverty as well as trade and agriculture, are receiving increasing consideration.

Thalassemia and iron deficiency in a group of northeast Thai school children: relationship to the occurrence of anemia

The cross-sectional study assessed anemia, thalassemia, and hemoglobinopathies, as well as iron deficiency, among 190 northeastern Thai school children aged 10 to 11 years. The aim was to analyze the reasons for anemia among the group. Hemoglobin concentration and other hematological parameters were determined using an automated blood cell counter. Beta-thalassemia and other hemoglobinopathies were identified by high performance liquid chromatography (HPLC) analysis of hemoglobin. Alpha-thalassemia was identified by polymerase chain reaction (PCR) and related techniques. Iron deficiency was assessed using serum ferritin (SF) <20 ng/ml as indicator. Based on the WHO criteria, anemia was defined by hemoglobin (Hb) level <11.5 g/dl. Twenty five out of 190 children (13.2%; 95% CI = 8.7-18.8%) were anemic. Iron deficiency was found in only two out of 190 children (1.0%; 95% CI = 0.1-3.8%), but the two iron deficient children were not anemic. The proportion of thalassemia and hemoglobinopathies among the group was 61.1% (95% CI = 53.7-68.0%). As underlying reasons for anemia, thalassemia and hemoglobinopathies were found in 22 out of 25 (88.0%) anemic children. Beta-thalassemia and homozygous Hb E seem to be important, while this was less obvious for heterozygous α-thalassemia and heterozygous Hb E.

CONCLUSION

The results suggest that thalassemia and hemoglobinopathies may be major contributing factors to the occurrence of anemia in this area among the children's population.

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.

Iron-fortified milk and noodle consumption is associated with lower risk of anemia among children aged 6-59 mo in Indonesia

BACKGROUND

Anemia is common among children in developing countries and is associated with decreased cognitive and physical development. Iron-fortified foods may decrease child anemia.

OBJECTIVE

The objective was to describe the association between iron-fortified milk and iron-fortified noodle consumption and anemia in children aged 6-59 mo.

DESIGN

Consumption of fortified milk and fortified noodles and child anemia were assessed in 81,885 families from rural and 26,653 families from urban slum areas in Indonesia.

RESULTS

The proportions of children who received fortified milk and noodles were 30.1% and 22.6%, respectively, in rural families and 40.1% and 48.9%, respectively, in urban families. The prevalence of anemia among children from rural families was 55.9% and from urban families was 60.8%. Children from rural and urban families were less likely to be anemic if they received fortified milk [odds ratio (OR): 0.76; 95% CI: 0.72, 0.80 (P < 0.0001) and OR: 0.79; 95% CI: 0.74, 0.86 (P < 0.0001), respectively] but not fortified noodles [OR: 0.98; 95% CI: 0.93, 1.09 (P = 0.56) and OR: 0.95; 95% CI: 0.88, 1.02 (P = 0.16), respectively] in multiple logistic regression models with adjustment for potential confounders. In rural families, the odds of anemia were lower when the child who consumed fortified milk also consumed fortified noodles or when the child who consumed fortified noodles also consumed fortified milk.

CONCLUSIONS

In Indonesia, consumption of fortified milk and noodles was associated with decreased odds of child anemia. Iron-fortified milk and noodles may be a strategy that could be applied more widely as an intervention to decrease child anemia.

Neonatal period: linking best nutrition practices at birth to optimize maternal and infant health and survival

Delayed umbilical cord clamping, immediate skin-to-skin contact, and early initiation of breastfeeding have been shown to be simple, safe, and effective and should be implemented in all deliveries, with very few exceptions. Although these practices can also prevent death, their importance extends beyond survival and optimizes both short-and long-term neonatal and maternal health and nutrition. Their implementation requires that they be integrated with one another and included with other standard lifesaving care practices. Leveraging knowledge of efficacious interventions into high-quality programs with broad coverage is often the main obstacle to improving neonatal and maternal health in low-income countries. To achieve results at-scale, attention must be given to increasing access to scientific information supporting evidence-based practices and addressing the skills needed to implement the recommended practices; establishing and communicating global, national, and local policies and guidelines for implementation in conjunction with advocacy and synchronization with other maternal and neonatal care efforts; reorganizing delivery care services; and monitoring and evaluation. This will require international investments similar to those being made for other lifesaving neonatal interventions. Neonatal vitamin A supplementation, recommended for implementation in Asia, is controversial, and the evidence for and against this recommendation is reviewed.

Effects of iron supplementation in nonanemic pregnant women, infants, and young children on the mental performance and psychomotor development of children: a systematic review of randomized controlled trials

BACKGROUND

Uncertainty exists regarding the effects of iron supplementation on neurodevelopmental outcomes in the absence of anemia.

OBJECTIVE

Our objective was to evaluate the effects of iron supplementation in nonanemic pregnant women and in nonanemic healthy children aged <3 y on the mental performance and psychomotor development of children.

DESIGN

In this systematic review, MEDLINE, EMBASE, and The Cochrane Library were searched through December 2009 for randomized controlled trials (RCTs).

RESULTS

None of 5 RCTs individually showed a beneficial effect of iron supplementation during early life on the Mental Developmental Index of the Bayley Scales of Infant Development at different ages throughout the first 18 mo. Meta-analysis of 3 RCTs (n = 561) showed that, compared with placebo, supplementation with iron had no significant effect on children's Mental Developmental Index at approximately 12 mo of age (weighted mean difference: 1.66; 95% CI: -0.14, 3.47). Three of 5 RCTs showed a beneficial effect of iron supplementation on the Psychomotor Development Index at some time points, whereas 2 did not. Meta-analysis of 3 RCTs (n = 561) showed significant improvement on the Psychomotor Development Index at approximately 12 mo of age in the iron-supplemented group compared with the control group (weighted mean difference: 4.21; 95% CI: 2.31, 6.12). Two RCTs showed no effect of iron supplementation on behavior. Neither of the 2 RCTs that addressed the influence of prenatal iron supplementation showed an effect of iron on either the intelligence quotient or behavioral status of the children.

CONCLUSION

Limited available evidence suggests that iron supplementation in infants may positively influence children's psychomotor development, whereas it does not seem to alter their mental development or behavior.

Once weekly low-dose iron supplementation effectively improved iron status in adolescent girls

Iron supplementation has been suggested as a strategy for prevention and treatment of iron deficiency (ID) and iron deficiency anemia (IDA) in many countries, but non-compliance of daily regimens and common dosage remain as major challenges. The aim of this study was to investigate the effects of low dose once weekly iron supplementation in adolescent girls. The study was designed as a community-based, randomized, supplementation trial. The initial sample consisted of 200 female high school students, aged 14-16 years old, of whom 193 students concluded the study. They were randomly selected and assigned into either iron-supplemented group (ISG) or iron-unsupplemented group (IUG). The ISG received 150 mg ferrous sulfate once weekly for 16 weeks, whereas the IUG received nothing. Weight, height, and hematological parameters were measured and compared between the two groups before and after the intervention. There was no significant difference between the initial measures of the two groups before the intervention. After 16 weeks of intervention, mean of hemoglobin and serum ferritin improved significantly in ISG compared to IUG. At the beginning of the study, percent of anemia, IDA, and ID in ISG were 12.5%, 8.3%, and 30.2%, whereas these figures for IUG in this period of study were 14.4, 10.3, and 38.2, respectively, which were not significantly different between the two groups. However, percentages of the above items at the end of study in ISG were 2.1%, 0%, and 21.9%, respectively. In contrast to IUG, all cases of IDA were abolished in the ISG. Our study showed that once weekly supplementation of 150 mg ferrous sulfate for 16 weeks significantly improved iron status in female adolescents and effectively treated IDA. There is no need for higher dosage of iron for supplementation that may cause adverse effects and bear higher costs.

Predictors of mortality in HIV-1 infected children on antiretroviral therapy in Kenya: a prospective cohort

Background

Among children, early mortality following highly active antiretroviral therapy (HAART) remains high. It is important to define correlates of mortality in order to improve outcome.

Methods

HIV-1-infected children aged 18 months-12 years were followed up at Kenyatta National Hospital, Nairobi after initiating NNRTI-based HAART. Cofactors for mortality were determined using multivariate Cox regression models.

Results

Between August 2004 and November 2008, 149 children were initiated on HAART of whom 135 were followed for a total of 238 child-years (median 21 months) after HAART initiation. Baseline median CD4% was 6.8% and median HIV-1-RNA was 5.98-log₁₀ copies/ml. Twenty children (13.4%) died at a median of 35 days post-HAART initiation. Mortality during the entire follow-up period was 8.4 deaths per 100 child-years (46 deaths/100 child-years in first 4 months and 1.0 deaths/100 child-years after 4 months post-HAART initiation). On univariate Cox regression, baseline hemoglobin (Hb) <9 g/dl, weight-for-height z-score (WHZ) < -2, and WHO clinical stage 4 were associated with increased risk of death (Hb <9 g/dl HR 3.00 [95% C.I. 1.21-7.39], p = 0.02, WHZ < -2 HR 3.41 [95% C.I. 1.28-9.08], p = 0.01, and WHO clinical stage 4, HR 3.08 [1.17-8.12], p = 0.02). On multivariate analysis Hb < 9 g/dl remained predictive of mortality after controlling for age, baseline CD4%, WHO clinical stage and weight-for-height z-score (HR 2.95 (95% C.I. 1.04-8.35) p = 0.04).

Conclusion

High early mortality was observed in this cohort of Kenyan children receiving HAART, and low baseline hemoglobin was an independent risk factor for death.

Introdução alimentar e anemia em lactentes do município de Campinas (SP)

OBJETIVO: Verificar a prevalência de anemia em crianças do município de Campinas, levando-se em consideração a introdução de alimentos complementares. MÉTODOS: Estudo transversal realizado com 354 crianças de seis a 12 meses de idade, sorteadas do Sistema de Informações de Nascidos Vivos da cidade de Campinas. Profissionais da área da saúde devidamente treinados realizaram entrevista domiciliar com as mães dos lactentes, as quais responderam a um questionário contendo dados sobre a introdução de alimentos e condições socioeconômicas. Ao final, coletou-se sangue capilar do lactente, para dosagem de hemoglobina com o Hemocue®. Foram consideradas anêmicas as crianças com concentrações de hemoglobina inferiores a 11g/dL. Os dados foram avaliados por análise de sobrevida para verificar a associação da introdução alimentar com a anemia. RESULTADOS: Dos lactentes estudados, 66,5% apresentaram níveis de hemoglobina <11g/dL. A introdução da dieta da família (p=0,036), pão (p=0,012), iogurte (p=0,006), refrigerante (p=0,005), balas (p=0,005) e dos salgadinhos de saquinho (p=0,013) foi mais precoce nas crianças com anemia. CONCLUSÕES: A inadequada introdução de alimentos pode ser considerada fator associado à anemia. Essas informações devem ajudar a direcionar, com maior precisão, os programas de prevenção e de combate dessa enfermidade no município.

Research needed to strengthen science and programs for the control of iron deficiency and its consequences in young children

The purpose of this article is to highlight critical research needs for the effective prevention and control of iron deficiency and its consequences in children living in low-income countries. Four types of research are highlighted: The first involves scaling up interventions that we know are effective, namely iron supplementation of pregnant women, delayed cord clamping at delivery, immediate and exclusive breast-feeding, and continued exclusive breast-feeding for approximately 6 mo. The second entails evaluation research of alternative interventions that are likely to work, to find the most cost-effective strategies for a given social, economic, and epidemiological context. This research is especially needed to expand the implementation of appropriate complementary feeding interventions. In this area, research needs to be designed to provide causal evidence, to measure cost-effectiveness, and to measure potential effect modifiers. The third is efficacy research to discover promising practices where we lack proven interventions. Examples include how to detect infants younger than 6 mo who are at high risk of iron deficiency, efficacious and safe interventions for those young high-risk infants, and best protocols for the treatment of severe anemia. The fourth includes basic research to elucidate physiological processes and mechanisms underlying the risks and benefits of supplemental iron for children exposed to infectious diseases, especially malaria. Strategic research in all 4 areas will ensure that interventions to control pediatric iron deficiency are integrated into national programs and global initiatives to make pregnancy safer, reduce newborn deaths, and promote child development, health, and survival.

Iron metabolism, malaria, and other infections: what is all the fuss about?

This article briefly describes how iron lies at the center of a host-pathogen battle for nutrients and why there are many theoretical reasons to suspect that administration of supplemental iron might predispose to infection. This is supported by in vitro and small animal studies, but meta-analysis of human epidemiological and intervention studies has found little evidence for most disease outcomes. Supplemental iron does appear to increase susceptibility to malaria as measured by a variety of malariometric indices. However, even in malarious areas, iron appears beneficial in iron-deficient subjects. The concerns about iron supplementation programs for children seem to be confined to Sub-Saharan Africa and to areas of high malaria endemicity, where it will be necessary to adopt a cautious approach to supplementation based either on screening out iron-replete children or combining iron administration with effective disease-control strategies.

Why iron deficiency is important in infant development

Infants who experience iron deficiency during the first 6-12 mo of life are likely to experience persistent effects of the deficiency that alter functioning in adulthood. A lack of sufficient iron intake may significantly delay the development of the central nervous system as a result of alterations in morphology, neurochemistry, and bioenergetics. Depending on the stage of development at the time of iron deficiency, there may be an opportunity to reverse adverse effects, but the success of repletion efforts appear to be time dependent. Publications in the past several years describe the emerging picture of the consequences of iron deficiency in both human and animal studies. The mechanisms for iron accumulation in the brain and perhaps redistribution are being understood. The data in human infants are consistent with altered myelination of white matter, changes in monoamine metabolism in striatum, and functioning of the hippocampus. Rodent studies also show effects of iron deficiency during gestation and lactation that persist into adulthood despite restoration of iron status at weaning. These studies indicate that gestation and early lactation are likely critical periods when iron deficiency will result in long-lasting damage.

Setting the stage for child health and development: prevention of iron deficiency in early infancy

Iron deficiency is estimated to be the most common nutritional deficiency worldwide and is particularly persistent among infants and children. The high prevalence of anemia in 6- to 9-mo-old children raises the concern that birth iron stores in some infants are inadequate to sustain growth and development through the first 6 mo of life, and postnatal factors are contributing to early depletion of iron stores and development of anemia. At the same time, there are concerns about negative effects of excess iron in infants. Maternal iron status, infant birth weight and gestational age, as well as the timing of umbilical cord clamping at birth all contribute to the establishment of adequate total body iron at birth. Postnatally, feeding practices and growth rate are factors that will affect how quickly birth iron is depleted during the first 6 mo of life. Under conditions in which maternal iron status, birth weight, gestational age, and umbilical cord clamping time are optimal, and exclusive breast-feeding is practiced, infants should have adequate iron stores for the first 6-8 mo of life. Under suboptimal conditions, infants may not reach this goal and may need to be targeted for iron supplementation before 6 mo of age.