Jeong Kyoung Sook, Park Hyewon, Ha Eunhee, Hong Yun-Chul, Ha Mina, Park Hyesook, Kim Bung-Nyun, Lee Soo-Jeong, Lee Kyung Yeon, Kim Ja Hyeong, Kim Yangho
Department of Occupational and Environmental Medicine, Dongguk University College of Medicine, Dongguk University Ilsan Hospital, Goyang, Republic of Korea.
Department of Child and Family Welfare, University of Ulsan, Ulsan, Republic of Korea.
J Trace Elem Med Biol. 2015 Jan;29:336-41. doi: 10.1016/j.jtemb.2014.08.014. Epub 2014 Sep 3.
To investigate whether blood lead concentrations are elevated in iron-deficient children, and to examine the association between iron deficiency and/or elevated blood lead concentration and cognitive deficits in children.
The present study is a component of the Mothers' and Children's Environmental Health (MOCEH) study, a multi-center birth cohort project in Korea that began in 2006. The study cohort consisted of 194 children who underwent testing of blood lead and serum C-reactive proteins (CRPs) and ferritin concentrations, and the Korean version of the Wechsler Preschool and Primary Scale of Intelligence, revised edition (WPPSI-R), at 60 months of age. In addition, the mothers' blood lead concentrations during pregnancy were included in the analyses. Multivariate linear regression analysis was performed to analyze the correlation between high blood lead and low serum ferritin concentrations, after adjustment for covariates, in children, as well as to analyze the association of verbal IQ with serum ferritin and blood lead concentrations.
Lead and ferritin concentrations were inversely and significantly associated in children after adjustment for covariates. Moreover, both concentrations were associated with verbal IQ, after adjustment for covariates, and each was associated with cognitive deficits after adjustment for the other. Sobel test statistics showed that blood lead concentration was a significant partial mediator for the relationship between iron deficiency and verbal IQ.
Due to the results discussed in the present study, cognitive deficit in children seems to be associated not only with iron deficiency, but also with blood lead concentration.
研究缺铁儿童的血铅浓度是否升高，并探讨缺铁和/或血铅浓度升高与儿童认知缺陷之间的关联。
本研究是韩国一项始于2006年的多中心出生队列项目——母婴环境健康（MOCEH）研究的一部分。研究队列由194名儿童组成，这些儿童在60个月大时接受了血铅、血清C反应蛋白（CRP）和铁蛋白浓度检测，以及韦氏学前及初小儿童智力测验修订版（WPPSI-R）的韩语版本测试。此外，分析中纳入了母亲孕期的血铅浓度。进行多变量线性回归分析，以分析儿童在调整协变量后高血铅与低血清铁蛋白浓度之间的相关性，以及分析言语智商与血清铁蛋白和血铅浓度之间的关联。
在调整协变量后，儿童的铅和铁蛋白浓度呈显著负相关。此外，在调整协变量后，两种浓度均与言语智商相关，且在相互调整后各自与认知缺陷相关。索贝尔检验统计结果表明，血铅浓度是缺铁与言语智商之间关系的显著部分中介因素。
基于本研究讨论的结果，儿童的认知缺陷似乎不仅与缺铁有关，还与血铅浓度有关。
