Supplementation and screening for iron-deficiency anemia (IDA) in young children may improve growth and development outcomes. The goal of this study was to review the evidence regarding the benefits and harms of screening and routine supplementation for IDA for the US Preventive Services Task Force.
We searched Medline and Cochrane databases (1996–August 2014), as well as reference lists of relevant systematic reviews. We included trials and controlled observational studies regarding the effectiveness and harms of routine iron supplementation and screening in children ages 6 to 24 months conducted in developed countries. One author extracted data, which were checked for accuracy by a second author. Dual quality assessment was performed.
No studies of iron supplementation in young children reported on the diagnosis of neurodevelopmental delay. Five of 6 trials sparsely reporting various growth outcomes found no clear benefit of supplementation. After 3 to 12 months, Bayley Scales of Infant Development scores were not significantly different in 2 trials. Ten trials assessing iron supplementation in children reported inconsistent findings for hematologic measures. Evidence regarding the harms of supplementation was limited but did not indicate significant differences. No studies assessed the benefits or harms of screening or the association between improvement in impaired iron status and clinical outcomes. Studies may have been underpowered, and control factors varied and could have confounded results.
Although some evidence on supplementation for IDA in young children indicates improvements in hematologic values, evidence on clinical outcomes is lacking. No randomized controlled screening studies are available.
To the Editor:
Primum non nocere is the mantra of medicine. We opine, without any polemics, that the review article on screening and routine supplementation for iron deficiency by McDonagh et al1 in the April 2015 issue of PEDIATRICS may indeed cause harm. The authors' analysis of recent poor quality articles may actively discourage pediatricians from screening for and supplementing to prevent iron deficiency. Iron deficiency is a well established cause of long-lasting neurocognitive deficits. The assertion that recent articles fail to convince the authors of the benefits of screening and routine supplementation for iron deficiency causes one to reflect about seminal articles on iron deficiency. Dr. Lozoff and colleagues have a long track record documenting the importance of preventing iron deficiency and its detrimental effects on neurocognitive function, which may be permanent.2-4 Ergo, the dearth of good quality studies may reflect the permanence of neurocognitive dysfunction caused by iron deficiency. The co-morbidity of lead toxicity and iron deficiency may exacerbate further neurocognitive dysfunction and this is yet another reason to make every effort to prevent iron deficiency. With over 80 person-years of clinical experience we are staunch believers of preventing iron deficiency via routine iron supplementation for all toddlers when cow milk consumption commences. There is no evidence that screening and routine supplementation for iron deficiency causes harm. We applaud PEDIATRICS for continuing to catalyze the intellectual curiosity of its readers.
References 1. McDonagh MS, Blazina I, Dana T, Cantor A, BougatsosC. Screening and routine supplementation for iron deficiency: A systemic review. Pediatrics 2015; 135(4): 723-733 2. Lozoff B, Jimenez E, Wolf AW. Long-term developmental outcome of infants with iron deficiency. N Engl J Med 1991; 325(10): 687-694 3. Lozoff B, Jimenez E, Smith JB. Double burden of iron deficiency in infancy and low socioeconomic status: a longitudinal analysis of cognitive test scores to age 19 years. Arch Pediatr Adolesc Med 2006; 160(11): 1108 -1113 4. Lozoff B, Smith JB, Kaciroti N, Clark KM, Guevara S, Jimenez E. Functional significance of early-life iron deficiency: outcomes at 25 years. J Pediatr 2013: 163(5): 1260-1266
Conflict of Interest:
None declared
McDonagh, et al (1) suggests as follows: "No studies evaluating the benefits or harms of screening programs for asymptomatic children ages 6- 24 months were found." Their review goes back only to 1996.
In a study of infants in 1980 using the free erythrocyte porphyrin test (2) several children were indentified with iron deficiency not recognized by hemoglobin or hematocrit. All were drinking more than a quart of whole milk per day.
The "simple" question: "How much cows milk does you child drink per day?" would identify the need for nutritional guidance and further evaluation of these children not only because of concerns about iron intake but also concerns about the lack of other nutrients important for child health.
1) McDonagh MS, Blazina I, Cantor A, Bougatsos C. Screening and Routine Supplementation for Iron Deficiency Anemia, A Systematic Review. Pediatrics 2015; 135:723-733 2) Dine, MS. Evaluation of the Free Erythrocyte Porphyrin (FEP) Test in a Private Practice; The Incidence of Iron Deficiency and Increased Lead Absorption in 9- to 13-Month-Old Infants. Pediatrics 1980; 65:303-306
Conflict of Interest:
None declared