CONTEXT: Iron deficiency anemia in infants can cause developmental problems. However, the relationship between iron status and cognitive achievement in older children is less clear. OBJECTIVE: To investigate the relationship between iron deficiency and cognitive test scores among a nationally representative sample of school-aged children and adolescents. DESIGN: The National Health and Nutrition Examination Survey III 1988-1994 provides cross-sectional data for children 6 to 16 years old and contains measures of iron status including transferrin saturation, free erythrocyte protoporphyrin, and serum ferritin. Children were considered iron-deficient if any 2 of these values were abnormal for age and gender, and standard hemoglobin values were used to detect anemia. Scores from standardized tests were compared for children with normal iron status, iron deficiency without anemia, and iron deficiency with anemia. Logistic regression was used to estimate the association of iron status and below average test scores, controlling for confounding factors. RESULTS: Among the 5398 children in the sample, 3% were iron-deficient. The prevalence of iron deficiency was highest among adolescent girls (8.7%). Average math scores were lower for children with iron deficiency with and without anemia, compared with children with normal iron status (86.4 and 87.4 vs 93.7). By logistic regression, children with iron deficiency had greater than twice the risk of scoring below average in math than did children with normal iron status (odds ratio: 2.3; 95% confidence interval: 1.1-4.4). This elevated risk was present even for iron-deficient children without anemia (odds ratio: 2.4; 95% confidence interval: 1.1-5.2). CONCLUSIONS: We demonstrated lower standardized math scores among iron-deficient school-aged children and adolescents, including those with iron deficiency without anemia. Screening for iron deficiency without anemia may be warranted for children at risk.
CONTEXT: Irondeficiency anemia in infants can cause developmental problems. However, the relationship between iron status and cognitive achievement in older children is less clear. OBJECTIVE: To investigate the relationship between iron deficiency and cognitive test scores among a nationally representative sample of school-aged children and adolescents. DESIGN: The National Health and Nutrition Examination Survey III 1988-1994 provides cross-sectional data for children 6 to 16 years old and contains measures of iron status including transferrin saturation, free erythrocyte protoporphyrin, and serum ferritin. Children were considered iron-deficient if any 2 of these values were abnormal for age and gender, and standard hemoglobin values were used to detect anemia. Scores from standardized tests were compared for children with normal iron status, iron deficiency without anemia, and iron deficiency with anemia. Logistic regression was used to estimate the association of iron status and below average test scores, controlling for confounding factors. RESULTS: Among the 5398 children in the sample, 3% were iron-deficient. The prevalence of iron deficiency was highest among adolescent girls (8.7%). Average math scores were lower for children with iron deficiency with and without anemia, compared with children with normal iron status (86.4 and 87.4 vs 93.7). By logistic regression, children with iron deficiency had greater than twice the risk of scoring below average in math than did children with normal iron status (odds ratio: 2.3; 95% confidence interval: 1.1-4.4). This elevated risk was present even for iron-deficient children without anemia (odds ratio: 2.4; 95% confidence interval: 1.1-5.2). CONCLUSIONS: We demonstrated lower standardized math scores among iron-deficient school-aged children and adolescents, including those with iron deficiency without anemia. Screening for iron deficiency without anemia may be warranted for children at risk.
Authors: Na Ri Kang; Yo Han Ahn; Eujin Park; Hyun Jin Choi; Seong Heon Kim; Heeyeon Cho; Min Hyun Cho; Jae Il Shin; Joo Hoon Lee; Young Seo Park; Hae Il Cheong; Hee Gyung Kang; Il-Soo Ha; Young Sook Kwack; Kyoung Hee Han Journal: Pediatr Nephrol Date: 2019-06-20 Impact factor: 3.714
Authors: Roberta J Ward; Robert R Crichton; Deanna L Taylor; Laura Della Corte; Surjit K Srai; David T Dexter Journal: J Neural Transm (Vienna) Date: 2010-09-29 Impact factor: 3.575
Authors: Khov Kuong; Marion Fiorentino; Marlene Perignon; Chhoun Chamnan; Jacques Berger; Muth Sinuon; Vann Molyden; Kurt Burja; Megan Parker; Sou Chheng Ly; Henrik Friis; Nanna Roos; Frank T Wieringa Journal: Am J Trop Med Hyg Date: 2016-08-29 Impact factor: 2.345