Iron and Neurodevelopment in Preterm Infants: A Narrative Review

Abstract

Iron is critical for brain development, playing key roles in synaptogenesis, myelination, energy metabolism and neurotransmitter production. NICU infants are at particular risk for iron deficiency due to high iron needs, preterm birth, disruptions in maternal or placental health and phlebotomy. If deficiency occurs during critical periods of brain development, this may lead to permanent alterations in brain structure and function which is not reversible despite later supplementation. Children with perinatal iron deficiency have been shown to have delayed nerve conduction speeds, disrupted sleep patterns, impaired recognition memory, motor deficits and lower global developmental scores which may be present as early as in the neonatal period and persist into adulthood. Based on this, ensuring brain iron sufficiency during the neonatal period is critical to optimizing neurodevelopmental outcomes and iron supplementation should be targeted to iron measures that correlate with improved outcomes.

Preterm Infants on Early Solid Foods and Iron Status in the First Year of Life—A Secondary Outcome Analysis of a Randomized Controlled Trial

“…There is consensus in the literature that iron deficiency anemia is related to later poor neurodevelopmental outcome [4]. Iron deficiency anemia affects myelination, synaptogenesis, alters metabolism, and neurotransmission causing altered brain structure and function leading to impaired cognitive, motor, and neurobehavioral development [5,6]. In the present study, >50% of infants in both groups suffered from iron deficiency after discharge.…”

“…Iron deficiency leads to poor short-and long-term health and neurodevelopmental outcomes in preterm infants [4]. Infants with iron deficiency are at risk of altered brain structure and function with impaired cognitive, motor, and neurobehavioral development due to altered metabolism and neurotransmission as well as effects of iron deficiency on myelination and synaptogenesis during brain growth [5,6]. Therefore, supplementation of iron is needed in the early life of preterm infants [4,7].…”

Lower iron stores were associated with suboptimal gross motor scores in infants at 3–7 months

“…If iron stores are sufficient for haemoglobin synthesis, ret‐Hb remains within normal limits, but with lower iron stores, ret‐Hb decreases 7 . Even though iron deficiency has been causally related to impaired neurodevelopment, 9 there are no studies on the relation of iron deficiency on motor development in infants younger than 6 months of age, 10 nor on the association between ret‐Hb and infant development 11 …”

“…7 Even though iron deficiency has been causally related to impaired neurodevelopment, 9 there are no studies on the relation of iron deficiency on motor development in infants younger than 6 months of age, 10 nor on the association between ret-Hb and infant development. 11 The aims of this prospective cohort study were to investigate associations between iron status and gross motor scores in infants aged 3-7 months and to evaluate their psychomotor function at 2 years of age.…”

Pregnancy outcomes in women with iron deficiency: a retrospective, monocenter study

“…Assessing the impact that maternal ID has on pregnancy outcomes and on early childhood development is more complex than it might seem at rst. While there are few prospective studies which prove that routine screening and iron supplementation have bene ts, ample evidence-based reports indicate that ID in mothers and infants causes signi cant morbidity (2)(3)(4)(5). During mild maternal ID, iron is prioritized to the fetus (6, 7).…”