Iron deficiency in 1- to 3-year-old children. A pediatric failure?

Is High Milk Intake Good for Children's Health? A National Population-Based Observational Cohort Study

Milk is widely considered as a beneficial product for growing children. This study was designed to describe the milk consumption status of Korean children aged 30–36 months and to investigate its association with the risk of obesity and iron deficiency anemia (IDA). This nationwide administrative study used data from the Korean national health insurance system and child health screening examinations for children born in 2008 and 2009. In total, 425,583 children were included, and they were divided into three groups based on daily milk consumption: low milk group (do not drink or drink <200 mL milk per day, n = 139,659), reference group (drink 200–499 mL milk per day, n = 255,670), and high milk group (drink ≥500 mL milk per day, n = 30,254). After adjusting variable confounding factors, the consumption of a large amount of milk of ≥500 mL per day at the age of 30–36 months was associated with an increased risk of obesity at the age of 42–72 months and IDA after the age of 30 months. These results may provide partial evidence for dietary guidelines for milk consumption in children that are conducive to health.

Universal versus Selective Iron Supplementation for Infants and the Risk of Unintentional Poisoning in Young Children: A Comparative Study of Two Populations

Background:

Iron continues to be a common cause of poisoning in young children, in part due to its widespread use and easy accessibility.

Objective:

To determine differences in the epidemiology and outcome of unintentional iron ingestion by young children in populations practicing selective (eg, US) versus universal (eg, Israel) iron supplementation to infants.

Methods:

All cases of unintentional iron ingestion in children younger than 7 years in a one year period were identified through the poison control center databases of 2 sites (Illinois and Israel). Parameters compared include patient sex and age; type, form, and dose of iron preparation; circumstances and clinical manifestations; management; and outcome.

Results:

A total of 602 children were identified: 459 in Illinois and 143 in Israel. The majority of Illinois children ingested multivitamin preparations (94%), whereas Israeli children ingested single-ingredient iron preparations (78%) (p < 0.001). Iron doses ingested were higher in Israel (median 14.5 vs 6.6 mg/kg; p < 0.001) but remained within the nontoxic range for most children. No deaths or severe poisonings were reported, and 93% of children in both groups were asymptomatic. The majority of ingestions in both locations were due to unintentional self-ingestion. However, parental miscalculation occurred more frequently in Israel (16%) than in Illinois (1%).

Conclusions:

Universal iron supplementation to infants was not associated with a negative impact on the outcome of pediatric unintentional ingestions. Low-dose exposures were safely managed by on-site observation.

Severe iron-deficiency anemia still an issue in toddlers

BACKGROUND AND OBJECTIVES

Chronic, severe iron-deficiency anemia (IDA) in the first years of life increases the risk of irreversibly compromised cognitive, affective, and motor development. While IDA in infants has decreased because of dietary changes (iron-fortified formula and delaying cow's milk), toddlers (13-36 months) are equally vulnerable to the adverse effects of IDA. We aimed to show that despite public health efforts, severe IDA remains a problem in toddlers and is associated with excess milk consumption.

METHODS

Retrospective chart review of children 6 to 36 months admitted to or evaluated by hematology at a children's hospital from January 1, 2005 to December 31, 2010 with a severe microcytic anemia (hemoglobin [Hb] <9 g/dL and mean corpuscular volume (MCV) <75 fL).

RESULTS

We identified 68 infants and toddlers with severe IDA; most (84%) were 13 to 36 months old. The mean Hb and MCV were 6.0 g/dL (range = 2.2-8.9 g/dL) and 54.0 fL (range = 45.5-69.8 fL), respectively. Fatigue, poor appetite, and pica were the most common symptoms, found in 43%, 29%, and 22% of patients, respectively. Only 41% of parents reported pale skin while 77% of physicians recorded it on physical exam. Daily cow's milk consumption surpassed 24 ounces for 47 of 48 children with reported intake; 11 consumed more than 64 ounces per day.

CONCLUSIONS

Despite current screening recommendations, severe IDA continues to be a problem in toddlers and strongly correlates with excess cow's milk consumption. This reiterates the importance of screening for IDA into routine toddler care.

Blood cadmium is elevated in iron deficient U.S. children: a cross-sectional study

BACKGROUND

Cadmium (Cd), a widespread environmental contaminant, and iron deficiency (ID), the most common nutrient deficiency in the world, are known risk factors for neurodevelopmental delays, as well as other disorders, in infants and children. Studies assessing the cumulative effects of these factors are lacking in children, despite concerns of increased uptake of metals in the presence of ID. Here we sought to determine if blood and urine Cd levels were elevated in ID children compared to non-ID children.

METHODS

Data for 5224 children, aged 3-19 years, were obtained from the 1999-2002 NHANES. ID was defined as ≥2 of 3 abnormal iron indicators (low serum ferritin [SF], high free erythrocyte protoporphyrin [FEP], low % transferrin saturation [TSAT]); ID anemia (IDA) was defined as ID plus low hemoglobin (Hgb). Logistic regression was used to evaluate associations between ID, IDA, and abnormal iron indicators and categories of blood and urine Cd.

RESULTS

Adjusted odds of ID, IDA, low SF, and low TSAT were associated with increasing category of blood Cd but not urine Cd. Adjusted ORs (95% CI) for blood Cd ≥0.5 μg/L versus < LOD were = 1.74 (1.30-2.34), 4.02 (1.92-8.41), 4.08 (2.36-5.89) and 1.78 (1.32-2.39), for ID, IDA, low SF, and low TSAT, respectively. Age and sex specific analyses of blood Cd and ID/abnormal iron indicators revealed that the observed associations were strongest in females aged 16-19 years.

CONCLUSIONS

Given their shared neurotoxic effects in children, and that many people live in areas with high burdens of both ID and Cd, more research into the complex relationships between nutrient deficiencies and environmental toxicants is vital.

Iron deficiency in infants and toddlers in the United States

Iron deficiency anemia (IDA) continues to be overwhelmingly the leading cause of anemia in early childhood and a global public health challenge. Although there has been a significant decrease in the frequency of IDA and iron deficiency (ID) in infants and toddlers in recent years in the United States, ID and IDA persist and the adverse effects of ID are long-lasting if not permanent. Moreover, ID can result in lead toxicity, and this toxic exposure, even with low levels, can impair neurocognitive function as well. This review describes the major steps that have taken place to decrease the frequency of ID and IDA.

Blood and hair lead in children with different extents of iron deficiency in Karachi

Childhood iron deficiency has a high incidence in Pakistan. Some but not all studies have shown that dietary iron deficiency may cause increased absorption of lead as both compete for the same transporters in the small intestine. Therefore, children in Pakistan, residing in heavily polluted cities like Karachi may be prone to lead poisoning. This hypothesis was tested by investigating blood and hair lead concentrations in children from Karachi who were divided into four groups of iron status; normal, borderline iron deficiency, iron deficiency and iron deficiency anaemia. A prospective observational study was conducted where 269 children were categorized into four groups of iron status using the World Health Organization criteria and one based on soluble transferrin receptor measurements. Blood iron status was determined using a full blood count, serum iron, ferritin, transferrin saturation and soluble transferrin receptor measurements. Blood lead was determined by graphite atomic absorption spectroscopy, whereas hair lead was assessed using an inductively coupled plasma atomic emission spectroscopy technique. Blood lead concentrations were significantly higher in children with iron deficiency anaemia (mean [95% confidence intervals] were 24.9 [22.6-27.2] μg/dL) compared to those with normal iron status (19.1 [16.8-21.4] μg/dL) using WHO criteria. In contrast, hair lead content was not significantly different in children of different iron status. Our findings reinforce the importance of not only reducing environmental lead pollution but also the development of national health strategies to reduce childhood iron deficiency in Pakistan.

Iron supplementation of breastfed infants

Reported here are three studies performed with the objective of finding ways to improve the iron status of breastfed infants and to prevent iron deficiency (ID). Participating infants were exclusively breastfed until 4 months of age; thereafter, they could receive complementary foods and, in some studies, supplemental formula. In the first study, infants were given medicinal iron between the ages of 1 and 5.5 months. During this period, iron status improved and ID was prevented; however, these benefits did not continue after the intervention ceased. In the second study, infants received medicinal iron or an equivalent amount of iron from an iron-fortified cereal between the ages of 4 and 9 months. Again, iron supplementation largely prevented ID from occurring, while non-anemic ID and ID anemia occurred in the control group as well as in the intervention groups before the intervention began. In the third study, infants received dry cereals fortified with electrolytic iron or with ferrous fumarate between the ages of 4 and 9 months. The cereals were equally effective in providing relative protection from ID. The results of these three studies indicate it is possible to protect breastfed infants from ID and IDA.

Evaluation of status of trace and toxic metals in biological samples (scalp hair, blood, and urine) of normal and anemic children of two age groups

Anemia affects a substantial portion of the world's population, provoking severe health problems as well as important economic losses to the region in which this condition is found. This study was designed to compare the levels of essential trace and toxic elements in scalp hair, blood, and urine samples of anemic children (n = 132) with age range 1-5 and 6-10 years of both genders. For a comparative study, 134 non-anemic age- and sex-matched children as control subjects, residing in the same city, were selected. The metals in the biological samples were measured by flame atomic absorption spectrophotometry/electrothermal atomic absorption spectrometry prior to microwave-assisted acid digestion. The proposed method was validated using certified reference samples of hair, blood, and urine. The results indicated significantly lower levels of iron, copper, and zinc in the biological samples as compared to the control children of both genders (p = 0.01-0.008). The mean values of lead and cadmium were significantly high in all three biological samples of anemic children as compared to non-anemic children of both age groups (p = 0.005-0.001). The ratios of essential metal to toxic metals in the biological samples of anemic children of both age groups were significantly lower than that of controls. Deficiency of essential trace metals and high level of toxic metals may play a role in the development of anemia in the subjects under study.

Caregiver health literacy and adherence to a daily multi-vitamin with iron regimen in infants

OBJECTIVE

To determine whether or not limited caregiver health literacy is associated with adherence to a daily multi-vitamin with iron regimen in infants.

METHODS

110 caregiver/infant dyads were enrolled in a prospective study to assess the relationship between caregiver health literacy and adherence to a daily multi-vitamin with iron regimen for infants. Households were contacted biweekly over a 3-month period. Adherence was based upon caregiver report. High adherence, our primary outcome, was defined as the administration of the multi-vitamin with iron on 5-7 days over the past week.

RESULTS

As measured by the Short Test of Functional Health Literacy in Adults (S-TOFHLA), 18% of caregivers had limited health literacy skills. Caregivers with limited health literacy skills were more likely to have higher adherence than caregivers with adequate health literacy, after adjusting for a number of possible confounding variables (AOR=2.13; 95% 1.20-3.78).

CONCLUSION

Caregivers with limited health literacy were twice as likely to report high adherence to a daily multi-vitamin with iron regimen in infants as caregivers with adequate health literacy in adjusted analysis.

PRACTICE IMPLICATIONS

Health literacy may exert a differential influence on adherence depending upon the complexity of the desired health behavior.

Excessive Cow's Milk Consumption and Iron Deficiency in Toddlers

Elimination of iron deficiency and iron deficiency anemia in children is a crucial public health concern because these conditions have been linked to cognitive and behavioral deficits. In the infant age group, great strides have been made to reduce iron deficiency and iron deficiency anemia significantly. However, similar progress has not yet been made with toddlers. Cow's milk consumption has long been associated with iron deficiency and iron deficiency anemia in children. Because cow's milk is a staple in the diet of most toddlers, they are at particular risk for these conditions. Two unusual presentations of anemia in toddlers caused by excessive cow's milk consumption are described: one in a child with congestive heart failure, the other in a child with profound eosinophilia. The role of cow's milk in iron deficiency and iron deficiency anemia is also examined.

Iron supplementation of low-income infants: a randomized clinical trial of adherence with ferrous fumarate sprinkles versus ferrous sulfate drops

OBJECTIVE

To determine whether low-income infants' adherence to nutritional supplementation with ferrous fumarate sprinkles was better than that with ferrous sulfate drops.

STUDY DESIGN

The study was a randomized clinical trial of healthy 6-month-old infants. Each infant received either a daily packet of sprinkles or a dropperful of liquid. Follow-up included alternating telephone and home visits biweekly for 3 months. Adherence was defined as high if the infant's caregiver reported supplement use on 5 to 7 days during the week before assessment. Side effects and caregiver attitude about supplements were secondary outcomes. Analyses were conducted using generalized estimating equations and chi(2) and Wilcoxon rank-sum tests.

RESULTS

A total of 150 of 225 eligible infants were enrolled. Adherence to supplementation was generally poor. High adherence ranged from 32% to 63% at any assessment in the subjects receiving drops, compared with 30% to 46% in those receiving sprinkles. The drops group was more likely to have at least four assessments with high adherence (22% vs 9.5%; P = .03). Caregivers of the drops infants were more likely to report greater than usual fussiness (P < .01); however, fussiness had no consistent impact on adherence.

CONCLUSIONS

The use of ferrous fumarate sprinkles rather than traditional ferrous sulfate drops did not improve adherence with daily iron supplementation in low-income infants.

Reticulocyte hemoglobin content for the diagnosis of iron deficiency

Identification of iron deficiency (ID) is essential to initiate early treatment to prevent long-term systemic complications of ID anemia. This study was undertaken to evaluate the efficiency of the parameter reticulocyte hemoglobin content (CHr) compared with other laboratory parameters in the assessment of ID in a pediatric population. Blood samples were obtained for 237 children who received routine pediatric care visits in a primary care clinic (mean age: 63.7 mo; male:female ratio: 1.08:1). A multiple stepwise logistic regression analysis identified CHr as the most accurate marker independently associated to ID. A CHr cutoff value of 25 pg (sensitivity: 94%; specificity: 80%) proved an optimal performance predicting ID. Therefore, we conclude that the hematologic parameter CHr constitutes a valuable screening tool for the identification of ID with or without anemia in childhood.

Food security, poverty, and human development in the United States

Access to food is essential to optimal development and function in children and adults. Food security, food insecurity, and hunger have been defined and a U.S. Food Security Scale was developed and is administered annually by the Census Bureau in its Current Population Survey. The eight child-referenced items now make up a Children's Food Security Scale. This review summarizes the data on household and children's food insecurity and its relationship with children's health and development and with mothers' depressive symptoms. It is demonstrable that food insecurity is a prevalent risk to the growth, health, cognitive, and behavioral potential of America's poor and near-poor children. Infants and toddlers in particular are at risk from food insecurity even at the lowest levels of severity, and the data indicate an "invisible epidemic" of a serious condition. Food insecurity is readily measured and rapidly remediable through policy changes, which a country like the United States, unlike many others, is fully capable of implementing. The food and distribution resources exist; the only constraint is political will.

Iron deficiency in early childhood in the United States: risk factors and racial/ethnic disparities

BACKGROUND

Iron deficiency affects 2.4 million US children, and childhood iron-deficiency anemia is associated with behavioral and cognitive delays. Given the detrimental long-term effects and high prevalence of iron deficiency, its prevention in early childhood is an important public health issue.

OBJECTIVES

The study objectives were to (1) identify risk factors for iron deficiency in US children 1 to 3 years old, using data from the most recent waves of the National Health and Nutrition Examination Survey IV (1999-2002) and (2) examine risk factors for iron deficiency among Hispanic toddlers, the largest minority group of US children.

PATIENTS AND METHODS

Analyses of the National Health and Nutrition Examination Survey IV were performed for a nationally representative sample of US children 1 to 3 years old. Iron-status measures were transferrin saturation, free erythrocyte protoporphyrin, and serum ferritin. Bivariate and multivariable analyses were performed to identify factors associated with iron deficiency.

RESULTS

Among 1641 toddlers, 42% were Hispanic, 28% were white, and 25% were black. The iron deficiency prevalence was 12% among Hispanics versus 6% in whites and 6% in blacks. Iron deficiency prevalence was 20% among those with overweight, 8% for those at risk for overweight, and 7% for normal-weight toddlers. Fourteen percent of toddlers with parents interviewed in a non-English language had iron deficiency versus 7% of toddlers with parents interviewed in English. Five percent of toddlers in day care and 10% of the toddlers not in day care had iron deficiency. Hispanic toddlers were significantly more likely than white and black toddlers to be overweight (16% vs 5% vs 4%) and not in day care (70% vs 50% vs 43%). In multivariable analyses, overweight toddlers and those not in day care had higher odds of iron deficiency.

CONCLUSIONS

Toddlers who are overweight and not in day care are at high risk for iron deficiency. Hispanic toddlers are more likely than white and black toddlers to be overweight and not in day care. The higher prevalence of these risk factors among Hispanic toddlers may account for their increased prevalence of iron deficiency.

Iron deficiency and anemia: disparity exists between children in American Samoa and children living within the US

BACKGROUND/OBJECTIVES

Healthy People 2010 emphasizes elimination of health disparity and improvements in anemia and iron deficiency (ID). The study purpose was to (1) determine the prevalence of anemia, ID and ID anemia (IDA) in children living in American Samoa and (2) compare the prevalence to that found in children living in the United States.

SUBJECTS/METHODS

A total of 211 children from American Samoa, aged 1-5 years of age, participated in this cross-sectional study. Prevalence of anemia, ID and IDA were determined and comparison made using data obtained from children living in the United States. Anemia was diagnosed as hemoglobin (Hb) <110.0 g/l, ID as erythrocyte protoporphyrin (EP) >70 mumol/mol heme and IDA as Hb <110.0 g/l and EP >70 mumol/mol heme.

RESULTS

Anemia, ID and IDA prevalence was 33, 70 and 33%, respectively. The results of children from the United States were as follows: anemia, 9%; ID, 10% and IDA, 2%. Within American Samoan children, ID is positively associated with being breastfed <6 months (P<0.05) and anemia and IDA with lower household income (P<0.05; P<0.01). Mean Hb was significantly lower (P<0.001) and mean EP was significantly higher (P<0.001) than those within children living in the United States.

CONCLUSION

To meet Healthy People 2010 goals in children aged 1-2 years, the prevalence of ID in children living in American Samoa would need to decrease from 83 to 5% and in children aged 3-5 years from 59 to 1%. It is critical to ensure that populations within the United States and its territories are provided appropriate resources to promote health and prevent disease.

Continuing anemia prevention strategies are needed throughout early childhood in low-income preschool children

OBJECTIVE

To assess anemia incidence and persistence in low-income preschool children in the United States.

STUDY DESIGN

Using 2000 to 2004 data from Center for Disease Control and Prevention's Pediatric Nutrition Surveillance System, we constructed 4 cohorts. Children in each cohort had a baseline hemoglobin measurement at either age 12 +/- 2 months (n = 583,149), 18 +/- 2 months (n = 399,223), 24 +/- 2 months (n = 382,605), or 36 +/- 2 months (n = 300,817) and a follow-up hemoglobin measurement 12 +/- 2 months later, when they were approximately 24, 30, 36, or 48 months old. Defining anemia as a hemoglobin level < 11.0 g/dL (< 24 months old) or hemoglobin < 11.1 g/dL (> or = 24 mo), we calculated anemia incidence and persistence in each cohort and used multiple logistic regression to identify associated factors (race, sex, birthweight, height, weight, breastfeeding).

RESULTS

Anemia incidence declined with age. Persistence remained approximately 30%. In each cohort, 70% of follow-up anemia cases were incident. Compared with white children, black children had greater odds of incident anemia at each follow-up age (odds ratio [OR], 1.84-2.09), while Native American children had lower odds at 36 and 48 months of age (OR, 0.68, 0.65). Both Asian and black children had greater odds of persistent anemia than white children at each age (OR, 1.73-2.60).

CONCLUSIONS

Most follow-up anemia in each cohort was incident, underscoring the importance of anemia prevention throughout early childhood in this population. Investigation of the causes of anemia is warranted.

Randomized controlled trial of bottle weaning intervention: a pilot study

Inappropriate baby bottle use is associated with tooth decay, anemia, and overweight, and it may adversely affect dietary patterns. Parents often do not follow guidance to wean by 18 months of life. We piloted a brief, counseling-based weaning intervention in an urban WIC agency among primarily Hispanic parent/toddler dyads. At baseline (n = 48), toddlers consumed a mean 4.7 bottles/day. At follow-up (n = 39), the intervention group consumed fewer mean bottles/day than controls (0.09 vs 2.0 bottles/day, P < .045). Half the toddlers in the experimental group and one third of the control groups weaned completely. Parents of weaned children were satisfied with the outcome.

Iron status of inner-city African-American infants

The iron status of African-American infants continues to be subject to debate. We characterized the iron status of 198 9-month-old inner-city infants (94% fed iron-fortified formula) using a comprehensive panel of measures and assessing lead and inflammation markers. The proportion with iron deficiency was calculated based on three approaches (> or = 2 abnormal iron measures with or without anemia for MCV model--NHANES II, ferritin model--NHANES III, or Sweden/Honduras study) and a promising new measure-body iron, calculated from ferritin and transferrin receptor (TfR). There were no sex differences for any iron measure. Hb < 110 g/l was observed in 25%; Hb < or = 105 g/l in 10.1%. Free erythrocyte protoporphyrin (FEP) values were elevated without elevated lead concentrations or an inflammatory response: mean FEP = 86.6 microg/dl red blood cells [75.5 micromol/mol heme]; 52.3% were > 80 microg/dl (1.42 micromol/l), almost half of which were accompanied by a second abnormal iron measure. The estimated prevalence of iron deficiency was 14.4, 5.3, and 2.5% for the MCV model, ferritin model, and Sweden/Honduras cutoffs, respectively, and 4.1% for body iron < 0 mg/kg. Regulation of iron storage is immature at < 1 year of age, making estimates of iron deficiency that depend on ferritin, including body iron, suspect in this age period. Thus, the "true" prevalence of iron deficiency could not be established with confidence due to major differences in the results, depending on the guidelines used. Functional indicators of poor iron status in young infants are urgently needed.

Child food insecurity and iron deficiency anemia in low-income infants and toddlers in the United States

OBJECTIVE

Examine the association between child-level food insecurity and iron status in young children utilizing community-based data from the Children's Sentinel Nutrition Assessment Program (C-SNAP).

METHODS

A cross-sectional sample of caregivers of children < or =36 months of age utilizing emergency department (ED) services were interviewed between 6/96-5/01. Caregiver interviews, which included questions on child-level food security, were linked to a primary clinic database containing hemoglobin, red blood cell distribution width, mean corpuscular volume, free erythrocyte protoporphyrin and lead values. Children a priori at-risk for anemia: birthweight < or =2500 g, with HIV/AIDS, sickle cell disease, or lead values > or =10.0 ug/dL, and children < or =6 months of age were excluded from the analysis. Only laboratory tests 365 days prior or 90 days after interview were examined. Iron status was classified in four mutually exclusive categories: 1) Iron Sufficient-No Anemia (ISNA), 2) Anemia (without iron deficiency), 3) Iron Deficient-No Anemia (IDNA), 4) Iron Deficient with Anemia (IDA).

RESULTS

626 ED interviews linked to laboratory data met the inclusion criteria. Food insecure children were significantly more likely to have IDA compared to food secure children [Adjusted Odds Ratio = 2.4, 95% CI (1.1-5.2), p = 0.02]. There was no association between child food insecurity and anemia without iron deficiency or iron deficiency without anemia.

CONCLUSION

These findings suggest an association between child level food insecurity and iron deficiency anemia, a clinically important health indicator with known negative cognitive, behavioral and health consequences. Cuts in spending on food assistance programs that address children's food insecurity may lead to adverse health consequences.

Differing perspectives of inner-city parents and pediatric clinicians impact management of iron-deficiency anemia

OBJECTIVE

To ascertain the beliefs and experiences of inner-city pediatric clinicians and parents regarding anemia in young children.

DESIGN

Focus groups and in-depth interviews.

SETTING

Pediatric clinics and community agencies in Hartford, Connecticut.

PARTICIPANTS

Convenience sample of 41 pediatric clinicians (93% white, 73% female) and 85 parents (100% minority, 88% female, 47% < 12 years education).

PHENOMENON OF INTEREST

Identification, understanding, and management of anemia.

ANALYSIS

Researcher pairs coded complete transcriptions. Recurrent themes were identified, which were then contrasted and compared between clinicians and parents.

RESULTS

Both clinicians and parents were familiar with, but frustrated by the persistence of anemia. They noted time constraints and poor communication during office visits as contributing to the problem. Parents felt alarmed upon initial diagnosis; linked anemia with heredity, food patterns, and activity; reported culturally linked management strategies; but were uncertain of the seriousness. Health clinicians saw physiological processes as outside the parents' understanding and emphasized prevention through feeding recommendations.

CONCLUSIONS AND IMPLICATIONS

In order to address childhood anemia effectively, differing socio-cultural perspectives of clinicians and parents need to be incorporated into a unified health care plan. Nutritionists are well suited to collaborate on the health care team to effectively address this issue.

Iron deficiency and impaired cognition in toddlers: an underestimated and undertreated problem

Iron deficiency in toddlers is associated with impaired cognition and is an underestimated and undertreated problem. The prevalence of iron deficiency anemia (IDA) during the first year of life has been dramatically reduced in developed countries, mainly due to the increase in breastfeeding and the use of iron-fortified feeding formulae. However, in US and UK children aged 1-2 years, recent studies have shown prevalence rates of >10% and 30% for IDA and iron deficiency, respectively. The daily iron intake in children aged 1-2 years is lower than in any other age group during life. IDA during the first 2 years of life is associated with impaired mental and psychomotor development and these deficits are long lasting, and perhaps irreversible, despite the correction of the anemia. Another compelling reason to prevent iron deficiency in children, especially in children aged 1-2 years, is the proven association of iron deficiency with increased lead absorption. Lead-associated cognitive deficits occur at blood lead levels <10 microg/L, a level once thought to be harmless. The current prevalence rates of iron deficiency and IDA in toddlers, especially among those in the lower socioeconomic groups, are unacceptably high. These young children are doubly at risk for neurodevelopmental impairment, both from the iron deficiency itself as well as from CNS damage caused by the associated increased lead absorption. The current screening and treatment recommendations for IDA in the US and in other developed countries appear to have been unsuccessful in preventing iron deficiency and IDA in a large number of toddlers. Similarly, the associated problem of impaired mental and psychomotor development has not been adequately recognized or addressed in the existing medical literature. The author recommends that, after breastfeeding or an iron-fortified formula is stopped, iron deficiency and IDA be prevented by routine daily supplemental doses of 10mg of elemental iron via iron-fortified vitamins, iron drops, or iron-fortified drinks.

An overview of evidence for a causal relationship between dietary availability of choline during development and cognitive function in offspring

This review is part of a series intended for non-specialists that will provide an overview of evidence for causal relationships between micronutrient deficiencies and brain function. Here, we review 34 studies in rodents linking the availability of choline during gestation and perinatal development to neurological function or performance of offspring in cognitive and behavioral tests. Experimental designs, major results, and statistical criteria are summarized in Tables 1-4. Based on our reading of the literature, the evidence suggests that choline supplementation during development results in improved performance of offspring in cognitive or behavioral tests, and in changes in a variety of neurological functional indicators: (1) enhanced performance was observed, particularly on more difficult tasks; (2) increases (choline supplementation) or decreases (choline deficiency) were observed in electrophysiological responsiveness and size of neurons in offspring; and (3) supplementation resulted in some protection against adverse effects of several neurotoxic agents (including alcohol) in offspring. Discussion topics include methodological issues, such as the importance of independent replication, causal criteria, and uncertainties in interpreting test results.

Anemia, iron deficiency, and iron deficiency anemia in 12-36-mo-old children from low-income families

BACKGROUND

Iron deficiency (ID) is the most common nutritional deficiency in the world and remains relatively common in at-risk groups in the United States. The actual prevalence of anemia, ID, and iron deficiency anemia (IDA) in California remains unclear.

OBJECTIVE

The objective was to determine the prevalence of anemia, low iron stores, ID, and IDA in children participating in the Special Supplemental Nutrition Program for Women, Infants and Children (WIC) population, and to assess the value of using hemoglobin to predict ID.

DESIGN

This was a cross-sectional study of a convenience sample of 12-36-mo-old children from WIC clinics in 2 California counties.

RESULTS

The prevalence of anemia was 11.1% (hemoglobin <110 g/L at 12-24 mo or <111 g/L at 24-36 mo). Study- and literature-determined abnormal values for iron measures were as follows: serum ferritin <or=8.7 or <10.0 microg/L, serum transferrin receptor >or=8.4 or >10.0 microg/mL, and transferrin saturation <or=13.2% or <10.0%, respectively. The prevalences of low iron stores (low ferritin) were 24.8% and 29.0%, of ID (>or=2 abnormal iron measures) were 16.2% and 8.8%, and of IDA (ID with low hemoglobin) were 3.4% and 3.2% on the basis of study- and literature-determined cutoffs, respectively. Hemoglobin concentration was used to predict study- and literature-determined ID on the basis of receiver operating characteristic curves. The sensitivity of low hemoglobin in predicting study- and literature-determined ID was low (23.2% and 40.0%, respectively).

CONCLUSIONS

Anemia and ID were prevalent in this WIC sample, but IDA was uncommon. Low hemoglobin is a poor predictor of ID.

Double-blind randomized evaluation of clinical and biological tolerance of polyethylene glycol 4000 versus lactulose in constipated children

OBJECTIVES

To assess the safety of a polyethylene glycol (PEG) 4000 laxative without additional salts in pediatric patients.

STUDY DESIGN

This was a 3-month multicenter, randomized, double-blind, double-dummy, lactulose-controlled, parallel study enrolling 96 ambulatory constipated children aged 6 months to 3 years, treated daily with 4-8 g PEG or 3.33 g-6.66 g lactulose. Total protein, albumin, iron, electrolytes, and vitamins B9 (folates), A and D (25OHD3) were measured in blood before and after treatment (day 84) in a central laboratory.

RESULTS

The percentage of children with at least one value out of normal range at day 84 with respect to baseline status (with or without at least one value out of normal range), i.e. the primary endpoint, was 87% and 90% in the PEG and lactulose groups, respectively, without any difference between groups. The whole blood parameters showed no qualitative or quantitative treatment-related changes. Vitamin A values were above normal range in 56% and 41% of children at baseline versus 33% and 36% at day 84 in the PEG and lactulose groups, respectively. Iron values were similarly under normal range in 47% and 51% at baseline versus 42% and 51% at day 84. Clinical tolerance was similar for both treatments except for vomiting and flatulence, which were significantly higher with lactulose. Significantly higher improvements were evidenced with PEG regarding stool consistency, appetite, fecaloma and use of additional laxatives.

CONCLUSION

This 3-month study in 96 constipated children aged 6 months to 3 years confirms the long-term tolerance of PEG 4000 in pediatrics and indicates a PEG efficacy similar to or greater than that of lactulose.

Is docosahexaenoic acid, an n-3 long-chain polyunsaturated fatty acid, required for development of normal brain function? An overview of evidence from cognitive and behavioral tests in humans and animals

This review is part of a series intended for nonspecialists that will summarize evidence relevant to the question of whether causal relations exist between micronutrient deficiencies and brain function. Here, we focus on experiments that used cognitive or behavioral tests as outcome measures in experimental designs that were known to or were likely to result in altered brain concentrations of the n-3 fatty acid docosahexaenoic acid (DHA) during the perinatal period of "brain growth spurt." Experimental designs reviewed include observational breastfeeding studies and randomized controlled trials in humans and studies in rodents and nonhuman primates. This review is based on a large number of expert reviews and commentaries and on some 50 recent studies in humans and animals that have not yet been included in published reviews. Expert opinion regarding the strengths and weaknesses of the major experimental systems and uncertainties associated with interpreting results is summarized. On the basis of our reading of this literature, we conclude that evidence from several types of studies, particularly studies in animals, suggests that, within the context of specific experimental designs, changes in brain concentrations of DHA are positively associated with changes in cognitive or behavioral performance. Additional experimental information required to conclude that a causal association exists is discussed, as are uncertainties associated with applying results from specific experimental designs to the question of whether infant formula should be supplemented with DHA.

The incidence, treatment, and follow-up of iron deficiency in a tertiary care pediatric clinic

To assess the incidence, treatment, and follow-up of iron deficiency in children seen in a tertiary hospital, a retrospective chart review was performed in 2002 of 364 consecutive children screened for iron deficiency with free erythrocyte protoporphyrin and hemoglobin. Sixty-five of the 352 children studied (18.5%) were iron-deficient and 19 patients (5.4%) were anemic. Eighty percent of the affected children were treated with iron, and only 25% had follow-up blood testing done. Iron deficiency is common in children younger than 2 years of age. Whether or not the children had anemia, treatment and follow-up were less than optimal.

Trends in diagnosis and management of iron deficiency during infancy and early childhood

Iron deficiency remains a public health challenge. The neurocognitive deficits that are associated with iron deficiency are most worrisome. Moreover, iron deficiency-associated elevated blood lead levels magnify the problem. Pediatricians must strive to prevent iron deficiency.

Daily multivitamins with iron to prevent anemia in high-risk infants: a randomized clinical trial

OBJECTIVE

The goal of this study was to assess the effectiveness of multivitamins with iron as prophylaxis against iron deficiency and anemia in infancy.

METHODS

The study was a double-blinded, randomized, pragmatic, clinical trial conducted at 3 urban primary care clinics. Subjects included healthy, full-term infants who were enrolled at their 6-month well-child visit. Infants were randomly assigned to receive standard-dose multivitamins with or without iron (10 mg/day). Parents administered multivitamins by mouth daily for 3 months. Laboratory results at 9 months of age were analyzed for the presence of anemia and/or iron deficiency. Anemia was defined as hemoglobin level <11.0 g/dL. Iron deficiency was initially defined as any abnormal laboratory value of the following: mean corpuscular volume combined with red cell distribution width or zinc protoporphyrin (with blood lead level <10 microg/dL) for most subjects and ferritin, transferrin saturation, or reticulocyte hemoglobin content for a subset. Subsequent analyses defined iron deficiency as any 2 abnormalities of the above laboratory outcomes, except hemoglobin.

RESULTS

The control (n = 138) and intervention (n = 146) groups were equivalent with respect to all important sociodemographic and nutritional variables. At 9 months of age, anemia was found in 21% of infants (n = 58). A total of 229 (81%) had iron deficiency on the basis of 1 abnormal laboratory indicator and 139 (49%) on the basis of 2 abnormal laboratory indicators. No difference existed in the occurrence of anemia and iron deficiency between the intervention and control groups. In the intervention group, 22% and 78% of 138, respectively, were anemic or had 1 abnormal laboratory outcome indicative of iron deficiency. In the control group, 19% and 84% of 144 were anemic or iron deficient. When stratified by adherence, no differences in hematologic outcomes between groups were noted. However, in multivariate logistic regression, infants whose mothers were anemic during pregnancy were 2.15 times more likely than others to have any laboratory abnormality (95% confidence interval: 1.14-4.07). Increasing adherence, regardless of group assignment, was associated with a 0.56 times reduced risk of any abnormality (95% confidence interval: 0.41-0.76).

CONCLUSION

On the basis of intention-to-treat analysis, multivitamins with iron was not effective in preventing iron deficiency or anemia in 9-month-old infants. However, effective prevention and treatment of maternal anemia during pregnancy and giving multivitamins with or without additional iron during infancy may prove to be important approaches to the prevention of iron deficiency among high-risk children. Because of the consequences of iron deficiency and its high prevalence among low-income infants, additional investigation in these areas is warranted.

Cocaine, anemia, and neurodevelopmental outcomes in children: a longitudinal study

This longitudinal study investigated the rates of iron-deficiency (ID) and iron-deficiency anemia (IDA) among prenatally cocaine-exposed and nonexposed two- and four-year-old children and assessed their relationships to neurodevelopmental outcomes. The sample consisted of 143 two-year-old (70 exposed and 73 nonexposed) and 274 four-year-old (139 exposed and 135 nonexposed) low socioeconomic status children recruited from an ongoing longitudinal study. Hematological assessments included hemoglobin, serum ferritin, mean corpuscular volume, transferrin saturation, and blood lead levels. The neurodevelopmental outcomes consisted of the Bayley Mental (MDI) and Motor (PDI) Development indices at two years, and the Wechsler Preschool and Primary Scales of Intelligence (WPPSI) and the Peabody Developmental Motor Scales (PDMS) at four years. The rate of IDA in four-year-old children was significantly greater among the cocaine-exposed compared to the nonexposed group (p =.026), while the rates at two years were not significant. Exposure to IDA at two years was associated with a significant decrease in concurrent motor scores (p =.011) after adjustment for relevant covariates. Peak exposure to IDA, defined as being anemic at 2 and/or 4 years of age, was associated with a significant (p <.05) decrease in Full Scale IQ after adjustment. Cocaine exposure was not a significant predictor of Full Scale IQ with the inclusion of peak IDA and lead in the model. These findings indicate the need for greater pediatric surveillance of IDA and lead in cocaine-exposed infants, in order to reduce long-term neuropsychological deficits.

Iron deficiency and risk factors for lower iron stores in 6–24-month-old New Zealanders

OBJECTIVES

To determine the prevalence of biochemical iron deficiency and identify factors associated with ferritin levels among 6-24-month-old urban South Island New Zealand children.

DESIGN

Cross-sectional survey conducted from May 1998 to March 1999.

SETTING

The cities of Christchurch, Dunedin and Invercargill.

SUBJECTS

A total of 323 randomly selected 6-24-month-old children participated (response rate 61%) of which 263 provided a blood sample.

METHODS

A complete blood cell count, zinc protoporphyrin, serum ferritin and C-reactive protein were measured on nonfasting venipuncture blood samples, 3-day weighed food records and general questionnaire data were collected.

RESULTS

Among children with C-reactive protein<10 mg/l (n=231), 4.3% had iron deficiency anaemia, 5.6% had iron deficiency without anaemia, and 18.6% had depleted iron stores, when a ferritin cutoff of < or =12 g/l was used. Age (negative), sex (girls>boys), ethnicity (Caucasian>non-Caucasian), weight-for-age percentiles (negative) and birth weight (positive) were associated with ferritin after adjusting for infection and socioeconomic status. When current consumption of iron fortified formula and >500 ml of cows' milk per day were included, these were associated with a 22% increase and 25% decrease in ferritin, respectively (R2=0.28).

CONCLUSIONS

The presence of suboptimal iron status (29%) among young New Zealand children is cause for concern, even though severe iron deficiency is rare, because children with marginal iron status are at risk of developing severe iron deficiency if exposed to a physiological challenge.

Prolonged bottle use and its association with iron deficiency anemia and overweight: a preliminary study

To determine the prevalence of prolonged bottle feeding practices in young children, and its association with body mass index (BMI) and iron deficiency anemia (IDA), we conducted a cross-sectional survey study at 3 Bronx, NY, WIC sites. Caregivers of 95 predominantly Hispanic and African-American WIC-enrolled children aged 18-56 months presenting for recertification completed questionnaires. Half were overweight (>85th% BMI) and 36% were obese (>95th% BMI); 21% met CDC criteria for anemia. Two thirds (63%) received daily bottles of milk or sweet liquids. Daily bottle use ranged from 3 to 10 (mean=3.3, median=3). Bottle use was significantly associated with obesity (>95th% BMI, p<0.0005), not significant with overweight (>85th% BMI, p<0.06) and statistically significant with IDA.

Screening for anemia in children: AAP recommendations--a critique

The American Academy of Pediatrics (AAP) recommends screening for anemia between the ages of 9 to 12 months with additional screening between the ages of 1 and 5 years for patients at risk. The screening may be universal or selective depending on the prevalence of iron deficiency anemia in the population. Improved infant rearing practices-including wider availability, acceptance, and use of iron-fortified formulas; iron fortification of foods; and increased awareness of the importance of dietary iron supplementation especially early in life-have lead to significant decline in the incidence of anemia in the first year of life. However, incidence of iron deficiency and ensuing anemia in children between 1 and 2 years continues to be significant and an important issue. Although iron deficiency may develop soon after cessation of or inadequate iron intake, anemia secondary to iron deficiency develops gradually over a period of several weeks to months. For children who have received/are receiving iron-fortified infant formulas and foods, hemoglobin screening at 9 to 12 months of age is inappropriate as there may not have been sufficient time to develop anemia, despite the rapid growth rate at this age. Widespread implementation of hemoglobin electrophoresis included in the neonatal metabolic screening programs in many states in the United States now has resulted in earlier diagnosis of hemoglobinopathies. Screening children at 9 to 12 months of age for hemoglobinopathies is somewhat redundant now. Screening for anemia before or around 1 year of age should continue to be important for communities and children at risk. Universal screening of toddlers at a later time allows sufficient time for nutritional anemia to become evident after the child has been weaned off iron-fortified formulas, for the influence of toddler dietary fads to manifest, and for evaluation of tolerance of cow's milk protein. This may be addressed via 2 approaches. The first involves postponing the currently recommended screening or an additional screening for anemia between 15 to 18 months of age. Determination of hemoglobin (or hematocrit) is not the optimal way to identify children at risk from effects of iron deficiency as it fails to identify patients who are iron-deficient but are not anemic. Long-term psychomotor, behavioral, and developmental effects secondary to iron deficiency anemia are known but sufficient data are lacking regarding the role of iron deficiency without anemia. Development and evaluation of sensitive, specific, and cost-effective screening tools to identify children at risk for iron deficiency is important. Until such methods are instituted, the AAP should emphasize and recommend universal screening for anemia during the second year of life.

Screening for iron deficiency anemia by dietary history in a high-risk population

BACKGROUND

Iron deficiency anemia (IDA) in young children is important to identify because of its adverse effects on behavior and development. Because of costs and inconvenience associated with blood test screening and the decline in prevalence of IDA, the Institute of Medicine and the Centers for Disease Control and Prevention recommend that blood test screening for IDA be targeted to children first identified by dietary and health history.

OBJECTIVE

To evaluate a parent-completed dietary and health history as the first stage of 2-stage screening for IDA.

DESIGN AND METHODS

A cross-sectional study was conducted in inner-city clinics in children 9 to 30 months old having routine anemia screening as part of a scheduled visit. Parents completed a questionnaire and children had venous blood sampling for complete blood count and ferritin. Anemia was defined as Hb <11.0 g/dL. Iron deficiency (ID) was defined as ferritin <10 microg/L or mean corpuscular volume <70 fL and red cell distribution width >14.5%. Children were categorized into 1 of 4 groups: iron-sufficient, not anemic (ISNA); iron-sufficient, anemic (ISA); iron-deficient, not anemic (IDNA); and iron-deficient anemic (IDA). The questionnaire consisted of 15 dietary items in domains of infant diet, intake of solid food, intake of beverages, and participation in the Special Supplemental Nutrition Program for Women, Infants, and Children together with 14 historical items in domains of birth history, recent illness, chronic medical conditions, history of anemia, and maternal history. Analysis was performed on individual items, domains, and combinations of selected items.

RESULTS

In the 282 study subjects, the prevalence of anemia (35%), IDNA (7%), and IDA (8%) did not vary significantly by age. Among individual historical and dietary questions, maternal history of anemia and drinking >2 glasses of juice per day identified the highest proportion of children with IDA: 50% sensitivity (95% confidence interval [CI]: 16,81) and 77% sensitivity (95% CI: 54,89), respectively. However, specificities for these questions were 60% (95% CI: 55,65) and 22% (95% CI: 17,27), respectively. Domains of questions with the highest sensitivity for IDA were beverage intake (91%; 95% CI: 68,99) and intake of solid food (91%; 95% CI: 68,99). However, specificities of the domains were only 14% (95% CI: 10,18) and 29% (95% CI: 24,35), respectively. The dietary items used by Boutry and Needlman were 95% (95% CI: 77, 99) sensitive but only 15% (95% CI: 11,19) specific for IDA. The recommendations of the Centers for Disease Control and Prevention for health and dietary screening were 73% (95% CI: 56,92) sensitive and 29% (95% CI: 24,35) specific for IDA. The individual questions, domains of questions, and interdomain groups of questions had similar sensitivity and specificity for anemia and ID (IDA + IDNA).

CONCLUSION

In this high-risk population, neither individual nor combinations of parental answers to dietary and health questions were able to predict IDA, anemia, or ID well enough to serve as a first-stage screening test.

Iron status of children in southern Sweden: effects of cow's milk and follow-on formula

AIM

The objective of the study was to investigate iron status in children in relation to intake of cow's milk and follow-on formula.

METHODS

In all, 367 healthy 2.5-y-old children were enrolled in the study. The amounts of cow's milk and formula consumed were recorded. B-haemoglobin, S-ferritin, S-iron, total iron binding capacity and mean corpuscular volume were analysed.

RESULTS

Seven percent of the children had iron deficiency anaemia (Hb <110g/l) and 10% had S-ferritin < 12 microg/l. Furthermore, 10% of the children were iron deficient, with or without anaemia. Children with iron deficiency had a higher intake of cow's milk (382 ml, 95% confidence interval (CI) 294-496, vs. 257 ml, CI 232-272, p < 0.0001), and fewer consumed follow-on formula (11% vs. 43%, p= 0.0002) compared to those with sufficient iron.

CONCLUSION

Iron deficiency is still common during childhood in Sweden. Intake of cow's milk is significantly higher in children with iron deficiency. In contrast, iron deficiency is less frequent among those consuming follow-on

The role of iron therapy in childhood plumbism

Iron deficiency and lead poisoning share common environmental risk factors and both are causes of neurocognitive toxicity. Despite their links epidemiologically, little is known of the effects of iron supplements on lead kinetics and toxicity. Nevertheless, iron is routinely prescribed in children with lead poisoning. Most of the existing data focus on the effects of preexisting iron deficiency on lead absorption. Animal studies demonstrate that iron-deficient animals have increased lead absorption. Lead-poisoned iron-deficient animals treated with iron supplements have demonstrated decreased lead excretion, a factor that might exacerbate lead toxicity while mitigating the effects of iron deficiency. Iron supplements given to children with iron deficiency and lead poisoning have been demonstrated to improve developmental assessment scores, an effect that is independent of blood lead concentration, suggesting that it is solely due to reversal of iron deficiency. Improvements in developmental assessment scores and decreases in blood lead in iron-replete children with lead poisoning secondary to iron supplements have not been demonstrated in clinical studies. Given these factors, the use of iron supplements in lead poisoning should be individualized, and the supplements should be provided only to patients who are iron deficient or who continue to live in lead-exposed housing.