Association between iron deficiency and blood lead level in a longitudinal analysis of children followed in an urban primary care clinic.
OBJECTIVE
To determine if iron deficiency (ID) is longitudinally associated with lead poisoning.


METHODS
Blood lead levels, hemoglobin, mean corpuscular volume (MCV), red cell distribution width (RDW), insurance status, and age were determined for 1,275 children. ID was defined as MCV <70 fl and RDW >14.5 if age was <2 years and MCV <73 fl and RDW >14.5 if age was >/=2 years. Logistic regression models were constructed by using the second-visit blood lead levels dichotomized at >/=0.48 microm/L (10 microg/dL) as the outcome.


RESULTS
The odds ratio (OR) for baseline ID predicting lead poisoning at the second visit was 4.12 (95% CI, 1.96-8.65). In the second model, using children who were iron-replete at both visits as the referent group, for children with ID at both visits, the OR for predicting lead poisoning at the second visit was 5.54 (95% CI, 2.25-13.62). For children with ID at the first visit and iron-replete at the second visit, the OR was 2.73 (95% CI, 0.90-8.27), and for children iron-replete at the first visit and ID at the second visit, the OR was 0.81 (95% CI, 0.10-6.30).


CONCLUSIONS
ID is associated with subsequent lead poisoning. These data are consistent with a biological mechanism of increased lead absorption among iron deficient children.
Wright
Robert O
RO
Department of Pediatrics, Children's Hospital, the Channing Laboratory, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
Tsaih
Shirng-Wern
SW
Schwartz
Joel
J
Wright
Rosalind J
RJ
Hu
Howard
H
D018798:Anemia, Iron-Deficiency / Q000097:blood / Q000150:complications* / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007854:Lead / Q000097:blood*; D007855:Lead Poisoning / Q000097:blood / Q000150:complications* / Q000453:epidemiology; D016015:Logistic Models; D008137:Longitudinal Studies; D008297:Male; D016017:Odds Ratio; D011320:Primary Health Care / Q000706:statistics & numerical data; D014481:United States / Q000453:epidemiology; D014505:Urban Population / Q000706:statistics & numerical data
D007854:Lead