Risk Factors For Iron Deficiency Research Articles

Iron Deficiency in Patients With Nonalcoholic Fatty Liver Disease Is Associated With Obesity, Female Gender, and Low Serum Hepcidin

Iron deficiency is often observed in obese individuals. The iron regulatory hormone hepcidin is regulated by iron and cytokines interleukin (IL) 6 and IL1β. We examine the relationship between obesity, circulating levels of hepcidin, and IL6 and IL1β, and other risk factors in patients with nonalcoholic fatty liver disease (NAFLD) with iron deficiency. We collected data on 675 adult subjects (>18 years old) enrolled in the Nonalcoholic Steatohepatitis Clinical Research Network. Subjects with transferrin saturation <20% were categorized as iron deficient, whereas those with transferrin saturation ≥20% were classified as iron normal. We assessed clinical, demographic, anthropometric, laboratory, dietary, and histologic data from patients, and serum levels of hepcidin and cytokines IL6 and IL1β. Univariate and multivariate analysis were used to identify risk factors for iron deficiency. One-third of patients (231 of 675; 34%) were iron deficient. Obesity, diabetes, and metabolic syndrome were more common in subjects with iron deficiency (P < .01), compared with those that were iron normal. Serum levels of hepcidin were significantly lower in subjects with iron deficiency (61 ± 45 vs 81 ± 51 ng/mL; P < .0001). Iron deficiency was significantly associated with female gender, obesity, increased body mass index and waist circumference, presence of diabetes, lower alcohol consumption, black or American Indian/Alaska Native race (P ≤ .018), and increased levels of IL6 and IL1β (6.6 vs 4.8 for iron normal, P ≤ .0001; and 0.45 vs 0.32 for iron normal, P ≤ .005). Iron deficiency is prevalent in patients with NAFLD and associated with female gender, increased body mass index, and nonwhite race. Serum levels of hepcidin were lower in iron-deficient subjects, reflecting an appropriate physiologic response to decreased circulating levels of iron, rather than a primary cause of iron deficiency in the setting of obesity and NAFLD.

Iron Homeostasis and Serum Hepcidin-25 Levels in Obese Children and Adolescents: Relation to Body Mass Index

Background/Aims: The etiology of the hypoferremia of obesity is unclear. Hepcidin is the body's main regulator of systemic iron (Fe) and has been reported to be elevated in obese patients. Thus, we aimed to assess Fe status and serum hepcidin-25 levels and their relationship with body mass index (BMI) in obese Egyptian children and adolescents. Methods: Fifty obese children were compared to 50 age-, sex- and pubertal stage- matched controls. All subjects were subjected to history and anthropometric assessment and measurement of serum Fe, total iron binding capacity (TIBC), ferritin, transferrin saturation (TS), soluble transferrin receptor (sTfR) and hepcidin. Results: Fe, TS and TIBC were lower, while ferritin, sTfR and hepcidin-25 were higher in obese patients than controls. BMI standard deviation score (SDS) correlated negatively with Fe (r = -0.82, p < 0.01), TS (r = -0.79, p = 0.02) and TIBC (r = -0.69, p = 0.02), and positively with ferritin (r = +0.73, p < 0.001), sTfR (r = +0.80, p < 0.01) and hepcidin (r = +0.95, p < 0.001). Higher BMI SDS and hepcidin were risk factors for iron deficiency (ID). Conclusions: Hypoferremia and elevated hepcidin-25 are prevalent in obese children and correlated with BMI SDS. The connection between hepcidin and inflammation could explain the association of ID with obesity.

Plasma Ferritin and Soluble Transferrin Receptor Concentrations and Body Iron Stores Identify Similar Risk Factors for Iron Deficiency but Result in Different Estimates of the National Prevalence of Iron Deficiency and Iron-Deficiency Anemia among Women and Children in Cameroon

Available iron status indicators reflect different aspects of metabolism. We compared the prevalence and distribution of iron deficiency (ID) and iron-deficiency anemia (IDA) among Cameroonian women and children, as measured by plasma ferritin, and soluble transferrin receptor concentrations, body iron stores (BIS), and hemoglobin, and evaluated the impact of adjustments for inflammation on these measures. In a nationally representative survey, we randomly selected 30 clusters in each of 3 zones (north, south, and large cities) and 10 households/ cluster, each with a child aged 12–59 mo and a woman 15–49 y. Ferritin and BIS were mathematically adjusted for inflammation, using plasma C-reactive protein and α1-acid glycoprotein both as continuous and categorical variables. Inflammation was present in 48.0% of children and 20.8% of women and anemia was diagnosed in 57.6% of children and 38.8% of women. Depending on the iron status indicator applied, the prevalence of ID ranged from 14.2 to 68.4% among children and 11.5 to 31.8% among women, and the prevalence of IDA ranged from 12.0 to 47.4% among children and 9.0 to 19.4% among women; the proportion of anemia associated with ID ranged from 20.8 to 82.3% among children and 23.2 to 50.0% among women. The different iron indicators generally identified similar groups at greatest risk of deficiency, using both conventional and derived cutoffs: younger children, pregnant women, and women and children in the north and rural areas. Research is needed to clarify the relationships between iron status indicators, particularly in the presence of inflammation, to harmonize global data on prevalence of ID.

Male gender is an important clinical risk factor for iron deficiency in healthy infants

Summary Background & aims To identify ID risk factors in infancy, and try to explore why ID is more prevalent in boys than in girls in the first year of life. Methods A multiple logistic regression was performed on data of 201 infants, with ferritin t test. Results From the 39 infants with IDA (19.4%), 24 (61.5%) were male and of the 162 infants without IDA, 50% were male ( p = 0.195). The median(minimum; maximum) ferritin concentrations in male infants at 9 months was of 9.8 ng/ml (0.5–67.0 ng/ml) and in females 14 ng/ml (0.5–74.5 ng/ml), p p = 0.027). A multiple logistic regression (OR; 95%CI) showed that male gender was the most important risk factor (OR: 3.3; 1.7–6.3; p p = 0.016) and longer breastfeeding time (OR: 1.1; CI [0.98; 1.2]; p = 0.099). Comparison of other haematological parameters at 9 months in relation to gender (males (M): 105; females (F): 96) showed significant differences in: mean ± SD, Mean Corpuscular Haemoglobin (M: 25.0 ± 2.1; F: 25.8 ± 2.4 pg, p = 0.001), Mean Corpuscular Volume (M: 73.4 ± 4.1; F: 75.3 ± 4.2 fl, 0.009), RDW (M: 14.6 ± 1.5; F: 14.1 ± 1.6%, p = 0.048), Plaquelets (M: 324.9 ± 77.9; F: 350.5 ± 81.4 × 10 3 /μl, p = 0.026). Conclusions ID was significantly more frequent in male infants, independent of rapid growth or longer breastfeeding duration. The clinical risk profile for ID in infants includes male gender and not only rapid growth, and longer breastfeeding duration.

Interaction between risk factors for iron deficiency in young children

AbstractAims: To describe interactions between risk factors for iron deficiency (ID).Methods: A random community sample of 316 children 6–23 months old of whom 13% had ID. Risk factors for ID were determined using logistic regression. Relative risks (RR) and 95% confidence intervals (95%CIs) were estimated. An additive relationship between risk factors was present if the RR of ID when both factors were present exceeded the sum of individual RRs of ID.Results: Independent risk factors for ID in a multivariate model were prematurity/low birthweight (RR 4.82, 95%CI 1.57–7.42), increased body mass index (5.57, 1.41–12.18), eating fruit only as a snack (3.48, 1.38–7.28), having no milk formula (4.40, 2.06–7.27), daily cow's milk (4.71, 1.99–8.56) and having only homemade first solids (2.91, 1.01–6.40). Eating fruit only as a snack had an additive relationship with three other dietary risk factors: no milk formula (RR 11.75, 95%CI 4.58–19.46), cow's milk daily (13.48, 1.20–42.37) and only homemade first solids (8.66, 3.43–14.76). Larger body mass had an additive relationship with four dietary factors: no milk formula (RR 14.69, 95%CI 1.95–24.00), fruit only as a snack (10.11, 4.59–16.36), cow's milk daily (12.28, 5.97–21.95) and only homemade first solids (7.05, 1.27–16.27). Prematurity/low birthweight had an additive relationship with two dietary risk factors: no milk formula (RR 9.16, 95%CI 2.42–12.11) and only homemade first solids (7.15, 1.47–9.73).Conclusions: Risk factors for ID interact to place young children at high risk of ID.

Iron biomarkers identify similar risk factors for iron deficiency but provide different estimates of the national prevalence of iron deficiency and iron‐deficiency anemia in Cameroon

Iron status indicators reflect different aspects of iron metabolism. We compared the prevalence and distribution of iron deficiency (ID) and iron‐deficiency anemia (IDA) in a national survey of Cameroonian women and children using plasma ferritin (F), soluble transferrin receptor (sTfR), body iron stores (BIS), and hemoglobin (Hb), with and without adjustments for inflammation. We randomly selected 30 clusters in each of 3 zones (North, South, and Large Cities) and 10 households (HH) per cluster, each with a woman 15–49 y and a child 12–59 mo (n=904 HH). Plasma F and BIS were adjusted for inflammation using C‐reactive protein and α1‐acid glycoprotein. Inflammation was present in 21% of women and 48% of children; 39% of women and 58% of children were anemic. The prevalence of ID ranged from 12–32% among women and 14–68% among children, depending on the iron status indicator, and IDA ranged from 9–19% among women and 12–47% among children. The proportion of anemia associated with ID ranged from 26–50% among women and 21–82% among children. However, the indicators identified similar groups at highest risk of ID and IDA: HH in the North and rural areas and younger children and pregnant women. SES was less consistently related to ID. Research is needed to clarify relationships among iron indicators, particularly during infection, to harmonize global data on ID and IDA.Grant Funding Source : Michael and Susan Dell Foundation, UNICEF

TMPRSS6, but not TF, TFR2 or BMP2 variants are associated with increased risk of iron-deficiency anemia

A variety of conditions lead to anemia, which affects one-quarter of the world's population. Previous genome-wide association studies revealed a number of genetic polymorphisms significantly associated with plasma iron status. To evaluate the association of genetic variants in genes involved in iron delivery and hepcidin regulation pathways with the risk of iron-deficiency anemia (IDA), the following single nucleotide polymorphisms were genotyped in 2139 unrelated elderly Chinese women: rs3811647 (TF), rs7385804 (TFR2), rs235756 (BMP2), and rs855791(V736A) and rs4820268 (TMPRSS6, encoding matriptase-2). We identified common variants in TMPRSS6 as being genetic risk factors for both iron deficiency (OR(rs855791) = 1.55, P = 4.96 × 10(-8)) and IDA (OR(rs855791) = 1.78, P = 8.43 × 10(-9)). TMPRSS6 polymorphisms were also associated with lower serum iron (SI) and hemoglobin levels, consistent with their associations to increased iron deficiency and anemia risk. Variants rs3811647 in TF and rs7385804 in TFR2 were associated with reduced SI, serum transferrin and transferrin saturation levels; however, these variants were not associated with iron deficiency or anemia risk. Our findings suggest that TF, TFR2 and TMPRSS6 polymorphisms are significantly associated with decreased iron status, but only variants in TMPRSS6 are genetic risk factors for iron deficiency and IDA.

Iron Deficiency and Fatigue in Adolescent Females with Heavy Menstrual Bleeding,

Abstract 4215 IntroductionAdolescent females are one of two pediatric populations at greatest risk for iron deficiency. An important risk factor for iron deficiency in adolescent females is excessive menstrual blood loss. Due in part to changes in circadian rhythms and poor sleep hygiene, fatigue is also a pervasive problem in adolescence, and may be exacerbated by iron deficiency secondary to menorrhagia. Clinical trials have shown that non-anemic adult women with low serum ferritin (≤15„30 ng/ml) and unexplained fatigue demonstrate improvement in fatigue with iron supplementation. Similar studies have not been performed in women <18 years of age. Our primary objective was to define baseline ferritin values and fatigue symptoms in a population of young females with a history of heavy menstrual bleeding. MethodsThe study population included 11,Ÿ17 year old females presenting to an Adolescent Gynecology Clinic or Menorrhagia Clinic for initial evaluation or follow-up of heavy menstrual bleeding. To mirror our clinical practice, the study population included patients who did and did not take iron supplements, as well as those who did and did not use hormonal contraception. To evaluate the degree and effects of menstrual blood loss, we utilized the Ruta Menorraghia Scale (RMS), a subjective measurement of menstrual blood loss and health-related quality of life. Possible responses to each multiple choice question were assigned ordinal scores to produce a total menorrhagia severity score (MSS). We investigated symptoms of fatigue using the Fatigue Severity Scale (FSS), a Likert scale measurement of fatigue’s effects, symptoms, and severity (possible responses range from 1 to 7). Hemoglobin and ferritin levels were obtained by venipuncture after the completion of survey instruments. A control population of 12,Ÿ17 year old menstruating females was recruited from a Sports Medicine clinic. These patients completed the RMS and FSS instruments but did not undergo venipuncture. We compared FSS and MSS between the two populations using the Kruskal Wallis test. We evaluated possible predictors of ferritin level (age, body mass index, fatigue scores, and MSS) using generalized linear models. ResultsA total of 31 adolescents diagnosed with heavy menstrual bleeding and 37 healthy adolescents completed the study. Mean MSS was 39.3 (±17.4) in those with a history of heavy menstrual bleeding, compared to 17.9 (±10.0) in controls (p<.0001). When completing the menorrhagia scale, over two-thirds (71%) of adolescents with heavy menstrual bleeding reported that menses mildly to moderately affected their ability to participate in physical education class or sports, compared to 27% of controls. Thirteen (41.9%) of those with heavy bleeding reported missing at least one day of school with each menses, compared to 8.1% of controls. Mean fatigue score was 4.2 (±1.5) in patients with heavy menstrual bleeding, similar to values reported in adults with sleep-wake disorders. In contrast, the mean fatigue score was 2.98 (±1.1, p=.001) in the control population, similar to values reported in normal healthy adults. Twenty-five of 31 (80.6%) adolescents with heavy menstrual bleeding had ferritin levels ≤30 ng/ml, and ten (32.2%) had ferritin levels ≤15 ng/ml. Our generalized linear models did not identify any significant univariate relationships between ferritin levels and patient age, body mass index, fatigue score, or menorrhagia score. This finding may be due to our small sample size, or the narrow range of ferritin levels in our study population (87% had a ferritin level <40 ng/ml). DiscussionIron deficiency and symptoms of fatigue were common findings in a small population of young women with heavy menstrual bleeding. Fatigue severity scores were significantly higher in our study population as compared to healthy controls. Larger studies are needed to delineate the relationship between menstrual blood loss, fatigue, and ferritin values in adolescents, in order to plan for future intervention trials of iron supplementation. We also identified a high frequency of physical activity limitations and school absence in young women with heavy menstrual bleeding, highlighting the importance of including these types of patient-reported outcomes in the design of clinical trials for this patient population. Disclosures:No relevant conflicts of interest to declare.

Maternal Stress During Pregnancy and Cord Ferritin Concentrations

Background and aims: Coe et al (2007) reported that maternal stress in monkeys during pregnancy is a risk factor for iron deficiency in infancy. The purpose of the present study was to compare cord ferritin concentration in newborns whose mothers were resident in a war zone during the first trimester of pregnancy (stress group) to those of newborns whose mothers became pregnant after the war (control group). Methods: One-hundred forty healthy mothers with no perinatal complications were recruited for the study in the delivery room. Sixty-three mothers were resident in a war zone during the first trimester of pregnancy and 77 became pregnant after the war. Cord-blood samples were taken to assess neonate iron status. Mothers were interviewed one day after delivery. Assessments of subjective stress during pregnancy were measured by a visual analog scale. Results: Cord Ferritin levels were lower for the stress group compared with the control group (145.71±61.9 and 169.26±85.4; p=.06). A Q-Q plot of the distribution of cord ferritin showed a clear separation between the two groups beginning with the third centile. From the fourth centile on the ferritin cord concentrations in the control group were always above that of the stress group (p< .1 by Kolmogorov-Smirnov goodness-of-fit test). Hierarchic regression showed that subjective stress predicts cord Ferritin overall (β=-.18, p< .05), and specifically in the stress group (β=-.37, p,.01). Conclusion: Our findings indicate that maternal subjective long-term stress during the first trimester of pregnancy is associated with lower concentrations of cord serum Ferritin.

241 Iron deficiency in non-anemic heart failure patients

Functional improvement has recently been reported in anemic and non-anemic heart failure (HF) patients with biological iron deficiency who were treated by intravenous iron substitution. Our aim was to show whether the non-anemic patients with iron deficiency have poorer functional tests than non-deficient ones. We included 138 HF patients without anemia from our HF department at Toulouse University Hospital into 2 groups: 1/low ferritin rate group (LFG) with a serum ferritin of 100 μg/L and lower (n = 42), 2/normal ferritin rate group (NFG) with serum ferritin over 100 μg/L (n = 96). We measured standard blood tests and functional parameters including NYHA status, 6 minute walk test (6’WT), and peak oxygen consumption (VO2 max). Baseline patient characteristics showed a slight difference for hemoglobin in non-anemic patients (LFG, 13.9; NFG, 14.4; p = 0.04) who have no difference for ejection fraction (LFG, 27.5%; NFG 29.5%; p = NS) between groups. The iron deficient patients tend to be older (59 versus 63 yo, p = NS) and most of them were women (92% in LFG versus 67% in NFG (p<0.05)). Functional parameters showed i) NYHA status of 2.29 in LFG versus 2.35 in NFG (p = NS); ii) 6’WT of 307 m in LFG versus 361 m in NFG (p = 0.006); and, iii) VO2 max of 13.8 ml/min/kg in LFG versus 15.7 ml/min/kg for the NFG (p = 0.04). Moreover, the LFG had a higher creatinin rate of 145 μmol/l versus 107 μmol/l for the NFG (p = 0.02). Iron deficient patients have poorer functional tests and are more likely to have renal insufficiency. Risk factors for iron deficiency in HF are the age and the female sex. We put in light some risk factors for iron deficiency that may help the practitioner making out which non-anemic HF patients should have blood tests to look for iron deficiency.

Excess Adiposity, Inflammation, and Iron-Deficiency in Female Adolescents

Iron deficiency is more prevalent in overweight children and adolescents but the mechanisms that underlie this condition remain unclear. The purpose of this cross-sectional study was to assess the relationship between iron status and excess adiposity, inflammation, menarche, diet, physical activity, and poverty status in female adolescents included in the National Health and Nutrition Examination Survey 2003-2004 dataset. Descriptive and simple comparative statistics ( t test, χ 2) were used to assess differences between normal-weight (5th≤body mass index [BMI] percentile <85th) and heavier-weight girls (≤85th percentile for BMI) for demographic, biochemical, dietary, and physical activity variables. In addition, logistic regression analyses predicting iron deficiency and linear regression predicting serum iron levels were performed. Heavier-weight girls had an increased prevalence of iron deficiency compared to those with normal weight. Dietary iron, age of and time since first menarche, poverty status, and physical activity were similar between the two groups and were not independent predictors of iron deficiency or log serum iron levels. Logistic modeling predicting iron deficiency revealed having a BMI ≥85th percentile and for each 1 mg/dL increase in C-reactive protein the odds ratio for iron deficiency more than doubled. The best-fit linear model to predict serum iron levels included both serum transferrin receptor and C-reactive protein following log-transformation for normalization of these variables. Findings indicate that heavier-weight female adolescents are at greater risk for iron deficiency and that inflammation stemming from excess adipose tissue contributes to this phenomenon. Food and nutrition professionals should consider elevated BMI as an additional risk factor for iron deficiency in female adolescents.

Tumor necrosis factor SNP haplotypes are associated with iron deficiency anemia in West African children

AbstractPlasma levels of tumor necrosis factor-α (TNF-α) are significantly raised in malaria infection and TNF-α is thought to inhibit intestinal iron absorption and macrophage iron release. This study investigated putative functional single nucleotide polymorphisms (SNPs) and haplotypes across the major histocompatibility complex (MHC) class III region, including TNF and its immediate neighbors nuclear factor of κ light polypeptide gene enhancer in B cells (lκBL), inhibitor-like 1 and lymphotoxin alpha (LTA), in relation to nutritional iron status and anemia, in a cohort of 780 children across a malaria season. The prevalence of iron deficiency anemia (IDA) increased over the malaria season (P < .001). The TNF−308 AA genotype was associated with an increased risk of iron deficiency (adjusted OR 8.1; P = .001) and IDA (adjusted OR 5.1; P = .01) at the end of the malaria season. No genotypes were associated with IDA before the malaria season. Thus, TNF appears to be a risk factor for iron deficiency and IDA in children in a malaria-endemic environment and this is likely to be due to a TNF-α–induced block in iron absorption.

Anemia and iron deficiency in pregnant Ghanaian women from urban areas

ObjectivesTo determine the prevalence and identify risk factors for iron deficiency and anemia in pregnant Ghanaian women from urban areas. MethodsA cross-sectional study of 452 healthy pregnant women receiving prenatal care in Accra, Ghana, was conducted. A sociodemographic health questionnaire was performed and hematologic parameters were measured. Logistic regression methods were used to identify risk factors for anemia and iron status. ResultsComplete data were available for 428 women. Anemia (hemoglobin <11 g/dL) was present in 144 (34%), iron deficiency (ferritin ≤16 μg/L) in 69 (16%), and iron deficiency anemia in 32 (7.5%) women. The adjusted odds ratio (OR) for anemia was 3.4 and 9.8 if iron deficiency and malaria parasitemia were present, respectively; the OR was 0.6 if women were at ≥36 weeks of pregnancy. The adjusted OR for iron deficiency was 2.7 if women were at ≥36 weeks of pregnancy and 0.12 if they had sickle trait. ConclusionAlthough anemia and iron deficiency remain substantial problems in pregnant Ghanaian women from urban areas, their prevalence is less than previously reported.

Prevalence and causes of iron deficiency anemias in infants aged 9 to 12 months in Estonia

To investigate the prevalence and causes of iron deficiency anemia in infants aged 9 to 12 months in Estonia. Every second child aged 9-12 months was randomly selected from primary medical centers in seven counties from all over Estonia. A questionnaire concerning eating habits and lifestyle was sent to their parents. Sixty-five percent (n=195) of contacted families agreed to participate in the study. Mean corpuscular volume and hemoglobin, serum ferritin, and soluble transferrin receptor levels were measured in 171 infants. Anemia was defined when hemoglobin level was lower than 105 g/L, and iron deficiency when ferritin level and mean corpuscular volume were lower than 12 microg/L and 74 fL, respectively. The prevalence of iron deficiency was 14.0% and iron deficiency anemia 9.4%. Birthweight less than 3000 g was the main risk factor for iron deficiency (OR=9.4; P<0.0005). Infants fed with breast milk and solid food had lower ferritin concentration (18.5 microg/L, 95% CI 14.0-23.0) than infants fed with formula and solid food (32.8 microg/L, 95% CI 26.6-39) (P<0.005). Iron deficiency anemia is common among 9-12-month-old Estonian infants. The main risk factor for iron deficiency was birthweight less than 3000 g.

Iron Deficiency in Early Childhood in the United States: Risk Factors and Racial/Ethnic Disparities

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. 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. 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. 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. 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.

Population prevalence and risk factors for iron deficiency in Auckland, New Zealand

Previous prevalence estimates of iron deficiency (ID) in young New Zealand children are inaccurate because of sampling bias and imprecise definition of ID. The aim of this study was to estimate the prevalence of ID in children aged 6-23 months and the factors associated with ID. An ethnically stratified sample identified from random residential address start points. Children resident in Auckland, New Zealand were enrolled from 1999 to 2002. Children with elevated C-reactive protein (>4 mg/L) were excluded. Iron status was determined in 324 (78%) of 416 enrolled children. Analyses adjusted for clustering and weighted for ethnic stratification. ID defined as abnormal values for two or more of serum ferritin (<10 microg/L), iron saturation (<10%) and mean cell volume (<73 fl). ID was present in 14% (95% confidence interval (CI) 9-17%). ID prevalence varied with ethnicity (Maori 20%, Pacific 17%, other 27%, New Zealand European 7%, P = 0.005), but not with social deprivation. In a multivariate analysis that adjusted for low birthweight, there was an increased risk of ID associated with a body mass index >or= 18.5 kg/m(2) (RR = 4.34, 95% CI 1.08-10.67), and with receiving no infant or follow on formula (RR = 3.60, 95% CI 1.56-6.49). ID is prevalent in young New Zealand children. Variance in ID prevalence with ethnicity but not social deprivation implies that cultural practices influence iron status. Young children with more rapid growth are at increased risk of ID as are those receiving milk other than that specifically modified for them.

The G277S transferrin mutation does not affect iron absorption in iron deficient women

Iron deficiency anaemia is one of the most important nutritional diseases, with high prevalence worldwide. The G277S transferrin mutation has been implicated as a risk factor for iron deficiency in menstruating women. However, the subject is controversial and there are no data concerning the possible influence of this polymorphism on iron absorption. To undertake a pilot study to investigate the effect of carrying the G277S transferrin mutation on non-haem iron absorption from a meal in young menstruating women compared to wild-type controls. Menstruating women with low iron stores (serum ferritin < 30 microg/l) or who had suffered from iron deficiency anaemia or had a family history of anaemia were recruited (n = 162). Haematological parameters were analysed, including haemoglobin, ferritin, total-iron binding capacity and transferrin saturation. Non-haem iron absorption from a meal was measured in 25 non-anaemic women either with the G277S/G277G (n = 10) or the wild type G277G/G277G (n = 15) genotype. The incorporation of stable isotopes of iron into erythrocytes was used to measure absorption. There were no significant differences in iron status indices or non-haem iron absorption between genotypes. However, G277S carriers did not show the usual inverse association between iron stores and non-haem iron absorption. Further studies should focus on the effects of a combination of polymorphisms in iron metabolism genes on iron absorption.

Iron deficiency in infancy: applying a physiologic framework for prediction

Infants aged 6-24 mo are at high risk of iron deficiency. Numerous studies worldwide have sought to identify predictors of iron deficiency in this age group. The objectives of the study were to apply a physiologic model to identify risk factors for iron deficiency and to consider those risk factors under different conditions of iron supplementation. We predicted that factors related to iron status at birth (lower gestational age and lower birth weight), postnatal needs for iron (more rapid growth), and bioavailable iron (more cow milk) would be major risk factors. The physiologic framework was assessed in 1657 Chilean infants (aged 12 mo) with birth weights >or=3 kg who were randomly assigned at age 6 mo to high or low iron supplementation or no added iron. Based on venous blood, the analysis used mean corpuscular volume and concentrations of hemoglobin, free erythrocyte protoporphyrin, and ferritin. Logistic regression models were used to identify predictors of iron deficiency anemia and iron deficiency without anemia. The prevalence of iron deficiency (>or=2 abnormal iron measures) was 34.9% at age 12 mo. Of 186 infants with hemoglobin concentrations <110 g/L, 158 (84.9%) were iron deficient. The only consistent (and the strongest) predictor of iron deficiency or iron deficiency anemia was lower 6-mo hemoglobin. Factors related to poorer iron status at birth (lower birth weight, shorter gestation though full-term, or both) were predictors in the no-added-iron and high-iron groups. Otherwise, predictors varied by iron supplementation. Variations in predictors of iron deficiency or iron deficiency anemia according to iron supplementation suggest that direct comparisons across studies are tenuous at best without data on early iron status and certainty that specific conditions are comparable.

Anemia in low-income exclusively breastfed infants

To verify the behavior of hemoglobin levels and anemia prevalence in full term infants, aged 3 to 6 months and on exclusive breastfeeding. A cross-sectional study of 242 infants aged 3 to 6 months with birth weights of more than 2,500 g, on exclusive breastfeeding and monitored by the Program for the Promotion of Infant Growth and Development, part of the Paraisópolis Einstein Community Program. Hemoglobin was assayed by finger prick between the third and sixth months of life. Anemia was defined as Hb < 10.3 g/dL (Saarinen) or Hb < 10 g/dL (Brault-Dubuc) for infants aged 3 to 5 months and as Hb < 11.0 g/dL (WHO) for infants aged 6 months. Mean hemoglobin concentration was 11.3 and 11.4 g/dL at 3 and 4 months and 11.2 and 11.1 g/dL at 5 and 6 months, respectively. The percentage of anemic infants varied depending on age and the cutoff adopted, being 11.8, 10.2 and 8.3% at 3, 4 and 5 months, respectively, according to the Brault-Dubuc criteria, and 20.6, 14.8 and 10.4% by the Saarinen criteria. Anemia prevalence at 6 months was 37.5%. Anemia prevalence rates observed among infants aged between 3 and 6 months varied from 8.3 to 37.5%, justifying increased attention on the part of pediatricians to the hemoglobin levels of infants who are on exclusive breastfeeding, come from low-income families and present risk factors for iron deficiency.

Injection Drug Use Is an Independent Risk Factor for Iron Deficiency and Iron Deficiency Anemia Among HIV-Seropositive and HIV-Seronegative Women

The risk factors for iron deficiency and iron deficiency anemia among female injection drug users are not well characterized. We measured hemoglobin and plasma ferritin and obtained demographic information and injection drug use history in the last 6 months in a cross-sectional study of 200 female injection drug users (134 HIV-positive and 66 HIV-negative). The women were participants in a natural history study, the AIDS Linked to Intravenous Experiences study in Baltimore, Maryland. In multivariate analyses adjusting for age, hepatitis C virus status, and HIV status, injection drug use within the last 6 months was associated with iron deficiency (odds ratio [OR] = 2.61, 95% confidence interval [CI]: 1.33 to 5.09) and iron deficiency anemia (OR = 6.65, 95% CI: 2.33 to 18.9). Among 134 HIV-positive women, injection drug use in the last 6 months was associated with iron deficiency (OR = 2.43, 95% CI: 1.08 to 5.48) and iron deficiency anemia (OR = 6.05, 95% CI: 1.82 to 20.1) in multivariate analyses adjusting for hepatitis C virus status and CD4 lymphocyte count. Injection drug use seems to be associated with iron deficiency and iron deficiency anemia. Further longitudinal studies are needed to gain insight into the nature of this association.