Lower Prevalence Of Iron Deficiency Research Articles

Predictors of iron status in well-nourished 4-y-old children

BackgroundIron status in childhood is influenced by diet. Other factors affecting iron status at that age are unclear. ObjectivesThe objectives of the study were to evaluate iron status in 4-y-old children, to track that status from infancy to childhood, and to examine the associations of iron status with dietary factors, growth, and heredity. DesignThis study consisted of a longitudinal follow-up at age 4 y of children (n = 127) from the cohort of a study that began at age 6 mo. Blood samples and anthropometry were assessed in both children and their parents; food records were collected from children only. ResultsDietary intake was not significantly correlated with hemoglobin concentrations, whereas the consumption of meat products had a positive effect on serum ferritin concentrations and mean corpuscular volume in boys (P = 0.015 and 0.04, respectively). The prevalences of anemia and iron deficiency were low, affecting 2 (1.8%) and 3 (2.8%) children, respectively; no child had iron deficiency anemia. There was significant within-subject tracking of hemoglobin and mean corpuscular volume from age 6 mo to 4 y. The mother's but not the father's hemoglobin correlated with the child's hemoglobin over time. ConclusionsFood choices had little effect on iron status. Hemoglobin concentrations and mean corpuscular volume were tracked from infancy to childhood. In healthy, well-nourished children with a low prevalence of iron deficiency, the mother's hemoglobin was significantly associated with that of her child, but the underlying mechanism is unclear.

THE EFFECTS OF SHORT-TERM IRON SUPPLEMENTATION ON IRON STATUS IN INFANTS IN MALARIA-ENDEMIC AREAS

Iron deficiency and Plasmodium falciparum malaria are the two main causes of anemia in young children in region endemic for this disease. The impact on iron status of prophylactic oral iron supplementation (2 mg/kg/day from two to six months of age) and the duration of this effect were assessed in a group of 832 Tanzanian infants exposed to P. falciparum malaria. Iron parameters and red blood cell indices were assessed at 2, 5, 8, and 12 months of age. Infants who received iron supplements had a significantly lower prevalence of iron deficiency (P < 0.01 at 5 months and P < 0.001 at 8 and 12 months). Red blood cell indices (mean corpuscular volume, mean cell hemoglobin, and mean cell hemoglobin concentration) were increased in children receiving iron supplementation and they did not differ between those protected and unprotected against malaria. The prevalence of ferropenia was similar in children protected against malaria and in those who were not protected and did not receive iron supplements (34.7% versus 37.3% at 12 months of age). We concluded that iron supplementation between the ages of 2-6 months improves iron status at least up to 12 months of age. Malaria infection does not contribute to iron deficiency.

Iron status in 358 apparently healthy 80-year-old Danish men and women: relation to food composition and dietary and supplemental iron intake.

In Denmark, the intake of dietary iron has decreased since 1987, when the mandatory iron fortification of flour (30 mg carbonyl iron/kg) was stopped. Since there have been no studies of iron status in elderly Danes after the abolishment of iron fortification, there is a need to assess actual iron status in the elderly population. The objective was to evaluate iron status and the relationship with food composition and dietary and supplemental iron intake in an elderly population in Copenhagen County. Participants in this health examination survey were 358 subjects (171 men, 187 women) 80 years of age from a 1914 cohort study. Blood samples included serum ferritin and hemoglobin (Hb). A dietary survey was performed in 232 subjects (120 men, 112 women) using a dietary history method. Median serum ferritin was 100 microg/l in men and 78 microg/l in women ( p<0.001). Ferritin concentrations <16 microg/l (i.e., depleted iron stores) were found in three men (2%) and in ten women (5%). Median Hb was 140 g/l in men and 131 g/l in women ( p<0.001). Three subjects (0.84%) had iron deficiency anemia (i.e., ferritin <13 microg/l and Hb <5th percentile for iron-replete subjects (121 g/l in men, 114 g/l in women). Ferritin concentrations >300 microg/l (i.e., iron overload) were found in 15 (9%) men and in 5 (3%) women. Median dietary iron intake was higher in men (8.7 mg/day) than in women (7.3 mg/day) ( p<0.001). Serum ferritin was positively correlated to dietary intake of iron, meat, and alcohol and to body mass index in men. Serum ferritin displayed a negative correlation to the consumption of tea. The use of vitamin-mineral supplements containing iron had no influence on iron status. Dietary intake of iron and/or the bioavailability of dietary iron were adequate to maintain a favorable iron status in 80-year-old subjects displaying a low prevalence of iron deficiency and a moderate prevalence of iron overload.

Tea consumption and iron status.

To give an overview of the association between tea consumption and iron status. A PUBMED search was performed (up to June 2001) for all publications containing the words: tea and ferritin, h(a)emoglobin, iron status or an(a)emia. Sixteen studies were evaluated in groups with high (infants, children and premenopausal women) or low prevalence of iron deficiency (men and the elderly). Of the 16 studies reviewed, six included infants and children, six premenopausal women, two men and two the elderly. In study groups with high prevalence of iron deficiency, tea consumption was inversely associated with serum ferritin and/or haemoglobin. The association disappeared when adjusting for confounding (dietary) factors, except for one study including 40% of iron deficient women. In groups with low prevalence of iron deficiency, tea consumption was not inversely associated with serum ferritin and/or haemoglobin. In those at risk for iron overload, such as middle-aged men, tea consumption may lower serum ferritin concentrations as reported in one study. This finding awaits further confirmation. This overview shows that tea consumption does not influence iron status in Western populations in which most people have adequate iron stores as determined by serum ferritin concentrations. Only in populations of individuals with marginal iron status does there seem to be a negative association between tea consumption and iron status.

Iron status of the free-living, elderly Framingham Heart Study cohort: an iron-replete population with a high prevalence of elevated iron stores

Although iron deficiency occurs commonly in vulnerable groups of women of reproductive age, infants, and children, less is known about the iron nutriture of the elderly. Our objective was to evaluate the iron status of a noninstitutionalized, elderly US population, with a particular focus on 2 concerns unique to the elderly: 1) potential confounding effects of chronic disease on iron measures and 2) increased occurrence of elevated iron stores. Multiple iron measures, including serum ferritin (SF), transferrin saturation, mean cell volume, and hemoglobin, were used to evaluate the prevalence of iron deficiency (ID), iron deficiency anemia (IDA), and other measures of iron nutriture in 1016 elderly white Americans aged 67-96 y from the Framingham Heart Study. "Diseased" subjects were defined as those with possible pathologically altered iron measures due to inflammation, infection, elevated liver enzymes, hereditary hemochromatosis, or cancer. The effect of altered iron status on various prevalence estimates was assessed. The elderly subjects had a low prevalence of ID (2.7%), IDA (1.2%), and depleted iron stores (3%; SF < 12 microg/L). In contrast, 12.9% had elevated iron stores (SF > 300 microg/L in men and SF > 200 microg/L in women), of which only 1% was attributable to chronic disease. The prevalence of ID, IDA, and depleted iron stores was unaffected by the presence of chronic disease. The Framingham Heart Study cohort is an iron-replete elderly population with a high prevalence of elevated iron stores in contrast with a low prevalence of iron deficiency, with insignificant effects of chronic disease on these iron status estimates. The likely liability in iron nutriture in free-living, elderly white Americans eating a Western diet is high iron stores, not iron deficiency.

Iron status with different infant feeding regimens: Relevance to screening and prevention of iron deficiency

The objective of this study was to evaluate the benefit of screening for anemia in infants in relation to their previous diet. The iron status of 854 nine-month-old infants on three different feeding regimens and on a regimen including iron dextran injection was determined by analysis of hemoglobin, serum ferritin, and erythrocyte protoporphyrin levels and of serum transferrin saturation. Infants were categorized as having iron deficiency if two or three of the three biochemical test results were abnormal and as having iron deficiency anemia if, in addition, the hemoglobin level was less than 110 gm/L. The prevalence of iron deficiency was highest in infants fed cow milk formula without added iron (37.5%), intermediate in the group fed human milk (26.5%), much lower in those fed cow milk formula with added iron (8.0%), and virtually absent in those injected with iron dextran (1.3%). The corresponding values for iron deficiency anemia were 20.2%, 14.7%, 0.6%, and 0%, respectively. The use of iron supplements is therefore justified in infants fed cow milk formula without added iron, even when there is no biochemical evidence of iron deficiency. The low prevalence of iron deficiency in the group fed iron-fortified formula appears to make it unnecessary to screen routinely for anemia in such infants. These results also support the recommendation that infants who are exclusively fed human milk for 9 months need an additional source of iron after about 6 months of age.

IRON STATUS IN FULL-TERM NEWBORN SMALL FOR GESTIONAL AGE

Iron nutrition was measured in 27 full-term newborn small for gestational age (SGA) during the first 4 months of age. Twenty seven preterm infants appropriate for gestational age (AGA) served as controls. Anthropometric and laboratory evaluations were performed at birth and monthly until 4 mo of age. A subgroup of infants (SGA n = 11; AGA n = 20) were supplemented with 3 mg/kg of iron (IBEROL®), from 2 to 4 mo of age. SGA infants presented a higher hemoglobin (Hb) concentration (p < 0.05) and an increased frequency of polycythemia at birth. AGA infants had a greater post-natal Hb drop (p < 0.02) at 2 months of age. At 4 mo of age there were no differences in Hb, serum ferritin (SF) and transferrin saturation between SGA and AGA infants. Iron supplementation resulted in higher Hb and SF levels at 4'mo of age (p < 0.05) and a lower prevalence of iron deficiency in both groups. We can conclude that full-term SGA and preterm AGA infants had no differences in iron nutriture status. Supported by: Abbott Laboratories de Chile, CONICYT Grant N°34/85 and Nestle Nutrition.

Nutritional iron status of infants fed according to current recommendations

We examined the iron nutritional status of healthy term infants in a longitudinal study from 15 through 365 days of age. All infants were fed according to the present austrian recommendations. Serum hemoglobin (Hb) decreased from 15 through 122 days of age and remained constant thereafter. At 365 days of age, only 4.7% of the infants had hemoglobin levels below 11 g/dl, which is considered the borderline value for anemia. Mean corpuscular volume (MCV) of erythrocytes was changing during infancy. Free erythrocyte protoporphyrin (FEP) was constant from 122 days through 365 days of age. The upper normal value of 3 micrograms/gHb for infants older than 122 days of age corresponded to that for children older than one year and adults. Serum ferritin (SF) decreased from 15 through 183 days of age and remained constant thereafter. At 365 days of age, only 9.3% of the infants had SF below 10 micrograms/l, which is considered the borderline concentration for depletion of iron stores. We found no differences of iron nutritional status between infants who were breastfed longer than 122 days and infants who were breastfed shorter than 122 days or were fed formula. Our findings indicate that the prevalence of iron deficiency anemia and depletion of the iron stores is lower than in previous studies. Changes in infant nutrition during the last years resulted in higher iron intake and lower prevalence of iron deficiency.

Serum ferritin and iron status of children in the Faroe Islands.

Iron status was assessed by measurement of serum ferritin (S-ferritin), transferrin saturation and haemoglobin (Hb) in 270 healthy Faroese children (153 males, 117 females) 4, 8 and 13 years old. There were no significant differences between the three variables in boys and girls. Geometric mean S-ferritin increased from 16 micrograms/l in 4-year-old children to 21 micrograms/l in 8-year-old (P less than 0.01) and 25 micrograms/l in 13-year-old children (P less than 0.05). Likewise Hb displayed a gradual increase with age (P less than 0.001); the arithmetic mean Hb was 129 g/l in 4-year-old, 137 g/l in 8-year-old, and 143 g/l in 13-year-old children. Depleted iron stores (i.e. S-ferritin less than 12 micrograms/l) were present in 21.5% of 4-year-old, and in 12.7% of 8 and 13-year-old children. Latent iron deficiency (i.e. S-ferritin less than 10 micrograms/l and transferrin saturation less than 10%) was found in 3.1% of 4-year-old and in 0.5% of 8 to 13-year-old children. None of the children had iron deficiency anaemia. A high dietary intake of animal protein probably explains the low prevalence of iron deficiency.