Efficacy and Safety of Iron Administration in Juvenile Populations

Abstract

Infantile iron deficiency anemia (IDA) reduces maximal lifetime cognitive capacity and can threaten the life of an adolescent mother in childbirth. Administration of iron is a component of strategies for preventing or reversing iron deficiency (ID) and iron can be given parenterally or as oral supplements or fortified food. Safety issues can arise at the point of administration, i.e. in the gut lumen, and as a consequence of excessive iron stores arising from the interventions. Recent improvements in the pharmacology of parenteral iron compounds open the way to greater consideration of the intravenous route in pediatric therapy, and even public health. Oral iron supplementation, usually with folic acid, is the main treatment of IDA in the clinical setting. It is often combined with multiple micronutrients and is also used for resolution of severe anemia at the community level and for prophylaxis in the nonanemic population. Fortification of staple food (such as flour), or age-specific foods (infant formula, complementary foods) and beverages are the usual methods for ID prophylaxis. Special iron-rich preparations (powders, crushable tablets, edible spreads) are available for home fortification. Biofortification, i.e. enriching the iron content of crops during cultivation, is a novel approach, yet to be fully implemented or evaluated for children. Side effects and toxicity after oral iron intake are seen in the gut lumen. After oral and parenteral iron intake, the rise in circulating iron can increase the risk of complications from coexisting infections, notably with malaria, and when individual iron status is adequate. Growth impairment occurs with exposure of iron-sufficient children to iron interventions, so that targeting of iron to ID individuals seems advisable. Numerous adverse consequences from accumulation of excessive total body iron stores show up as a consequence of iron-mediated oxidative stress. Incomplete maturation of iron homoeostasis may permit higher iron absorption before 6 months of age.

Can Iron Supplementation be Reconciled with Benefits and Risks in Areas Hyperendemic for Malaria?

“…An insufficient amount of iron impairs its essential functions, leading to a number of adverse consequences, including impairment of oxygen transport and storage by hemoglobin and myoglobin; compromising adequate provision of cellular ATP by iron-containing proteins, such as cytochromes; and reducing the disposal of potentially toxic xenobiotics. Moreover, adequate DNA synthesis by ribonucleotide reductase is compromised, impairing growth and cellular immune defense [30,31] as well as mental and motor development in children [32,33]. The rates of stillbirth and small-for-gestational age deliveries increase [34].…”

Prevention of Iron Deficiency in Infancy, Childhood and Adolescence

“…The concerns with iron supplementation in early infancy and the interactions between iron and infection are reviewed elsewhere in this issue [11,103] . The WHO recommends avoidance of large doses of iron supplementation in populations with a low prevalence of ID [85] .…”

Prevención de la carencia de hierro en la lactancia, la infancia y la adolescencia

“…Los temores que suscita el aporte complementario de hierro en la primera lactancia y las interacciones entre hierro e infección se revisan en otro lugar de este número [11,103] . La OMS recomienda evitar grandes dosis de aporte complementario de hierro en poblaciones con baja prevalencia de CH [85] .…”