Effects of iron therapy on infant blood lead levels☆
Received 9 December 2002; received in revised form 31 July 2003; accepted 22 August 2003.
Abstract
Objectives
To determine the effects of iron therapy on blood lead levels in infants with mildly elevated lead levels and varied iron status.
Methods
Infants from a community-derived sample in Costa Rica were categorized into five groups. Group 1 had iron-deficiency anemia with hemoglobin levels ≤105 g/L. Infants in group 2 were iron-deficient with intermediate hemoglobin levels (between 106-119 g/L). These groups were treated with intramuscular iron or 3 months of oral iron. Group 3 (nonanemic iron-deficient) and group 4 (nonanemic iron-depleted) were treated with 3 months of oral iron. Group 5 (iron-sufficient) received oral placebo.
Results
After 3 months of oral iron therapy, nonanemic iron-depleted infants had the greatest decrease in lead levels, followed by nonanemic iron-deficient infants and iron-deficient infants with hemoglobin levels <120 g/L. Lead levels increased among iron-deficient infants with hemoglobin levels <120 g/L who received intramuscular iron and iron-sufficient nonanemic infants who received placebo.
Conclusions
Changes in lead levels corresponded closely to changes in iron status and were plausible in terms of absorption mechanisms for lead and iron. Correcting and/or preventing iron deficiency appear to be rapid and effective means of improving infant lead levels, even in nonanemic infants.
From the Department of Psychiatry, MetroHealth Medical Center, School of Medicine, Case Western Reserve University, Cleveland, Ohio; the Hospital Nacional de Ninos, University of Costa Rica, San Jose, Costa Rica; and the Center for Human Growth and Development, Department of Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, Michigan USA
Reprint requests: Abraham W. Wolf, PhD, Department of Psychiatry, MetroHealth Medical Center, 2500 Metro Health Dr, Cleveland, OH 44109.
☆ Supported by NIH grants R01 HD31606-08 and R01-HD33487-06, to B. L., Principal Investigator.