ABSTRACT
BACKGROUND/OBJECTIVES: Preterm infants are at risk of iron deficiency (ID). In the Netherlands, preterm infants born after 32 weeks of gestational age (GA) do not receive iron supplementation on a routine basis. We hypothesized that dietary iron intake in these infants might not be sufficient to meet the high iron requirements during the first 6 months of life. SUBJECTS/METHODS: In a prospective cohort study, we analyzed the prevalence and risk factors of ID in 143 infants born between 32+0 and 36+6 weeks GA who did not receive iron supplementation. RESULTS: ID at the age of 4 and 6 months was present in 27 (18.9%) and 7 (4.9%) infants. Results of a multivariable logistic regression analysis showed that ID was associated with lower birth weight, a shorter duration of formula feeding, more weight gain in the first 6 months of life and lower ferritin concentrations at the age of 1 week. CONCLUSIONS: Preterm infants born after 32 weeks GA have an increased risk of ID compared with those born at term, supporting the need of iron supplementation. Our results suggests that measurement of ferritin at the age of 1 week might be useful to identify those infants at particular risk and could be used in populations without general supplementation programs. However, the efficacy and safety of individualized iron supplementation, based on ferritin concentrations at the age of 1 week, together with other predictors of ID, needs to be further investigated, preferably in a randomized controlled trial.
Subject(s)
Anemia, Iron-Deficiency/diet therapy , Gestational Age , Infant, Premature/metabolism , Iron, Dietary/administration & dosage , Iron/blood , Anemia, Iron-Deficiency/blood , Anemia, Iron-Deficiency/epidemiology , Cohort Studies , Dietary Supplements , Female , Ferritins/blood , Humans , Infant Formula/chemistry , Infant, Low Birth Weight/blood , Infant, Low Birth Weight/growth & development , Infant, Newborn , Infant, Premature/growth & development , Iron Deficiencies , Male , Netherlands/epidemiology , Pregnancy , Prevalence , Prospective Studies , Risk FactorsABSTRACT
OBJECTIVES: Reticulocyte hemoglobin (Ret-Hb) content and soluble transferrin receptor (sTfR) are described as promising biomarkers in the analysis of iron status. However, the value of Ret-Hb and sTfR in the early detection of iron depletion, as frequently observed in children in high-income countries, is unclear. We hypothesized that young children to iron depletion, using the WHO cutoff of ferritin <12 µg/l, would have lower Ret-Hb and higher sTfR concentrations compared to children with a ferritin ⩾level 12 µg/l. SUBJECTS/METHODS: In this cross-sectional study, we analyzed mean concentrations of Ret-Hb and sTfR in 351 healthy children aged 0.5-3 years in a high-income country. The Student's t-test was used to compare Ret-Hb and sTfR concentrations between groups. RESULTS: We showed that concentrations of Ret-Hb and sTfR are similar in children with and without iron depletion. A decrease in Ret-Hb concentration was present only when ferritin concentrations were <8 µg/l. sTfR concentrations were similar in children with ferritin concentrations <6 µg/l and ⩾12 µg/l. CONCLUSIONS: Our results showed that the discriminative value of Ret-Hb and sTfR for the detection of iron depletion is limited. Our findings suggest that ferritin is the most useful biomarker in the screening of iron depletion in healthy children in high-income countries. However, ideally, reference ranges of iron status biomarkers should be based on studies showing that children with concentrations outside reference ranges have poor neurodevelopmental outcomes.
