title: Cognitive Performance and Iron Status are Negatively Associated with Hookworm Infection in Cambodian Schoolchildren.
abstract: Soil-transmitted helminth (STH) infection has been associated with lower cognitive performance of schoolchildren. To identify pathways through which STH infection might affect school performance, baseline data from a large rice-fortification trial in Cambodian schoolchildren were used to investigate associations between STH infection, micronutrient status, anemia, and cognitive performance. Complete data on anthropometry, cognitive performance, and micronutrient status were available for 1,760 schoolchildren, 6-16 years of age. STH infection was identified using Kato-Katz, whereas cognitive performance was assessed using Raven's Colored Progressive Matrices (RCPM), block design, and picture completion. STH infection was found in 18% of the children; almost exclusively hookwork infection. After adjusting for age and gender, raw cognitive test scores were significantly lower in hookworm-infected children (-0.65; -0.78; -2.03 points for picture completion, RCPM, and block design, respectively; P < 0.05 for all). Hookworm infection was associated with iron status (total body iron), but not with vitamin A and zinc status, nor with inflammation or anthropometry. Body iron was negatively associated with increased intensity of hookworm infection (R = 0.22, P < 0.001). Hookworm infection in Cambodian schoolchildren was associated with lower cognitive performance, an effect most likely mediated through lower body iron. Interventions that are more effective against hookworm infection are needed to contribute to better health and improvement of cognitive performance.
authors: Department of Fisheries Post-Harvest Technologies and Quality Control, Ministry of Agriculture, Forestry and Fisheries, Phnom Penh, Cambodia. Department of Nutrition, Exercise and Sports, University of Copenhagen, Denmark. kuong.kh@gmail.com.
authors: Khov
authors: K
authors: Kuong
authors: Institut de Recherche pour le Développement, Montpellier, France.
authors: Marion
authors: M
authors: Fiorentino
authors: Institut de Recherche pour le Développement, Montpellier, France.
authors: Marlene
authors: M
authors: Perignon
authors: Department of Fisheries Post-Harvest Technologies and Quality Control, Ministry of Agriculture, Forestry and Fisheries, Phnom Penh, Cambodia.
authors: Chhoun
authors: C
authors: Chamnan
authors: Institut de Recherche pour le Développement, Montpellier, France.
authors: Jacques
authors: J
authors: Berger
authors: National Center for Parasitology, Entomology and Malaria Control, Phnom Penh, Cambodia.
authors: Muth
authors: M
authors: Sinuon
authors: National Center for Parasitology, Entomology and Malaria Control, Phnom Penh, Cambodia.
authors: Vann
authors: V
authors: Molyden
authors: United Nations World Food Program, Phnom Penh, Cambodia.
authors: Kurt
authors: K
authors: Burja
authors: PATH, Seattle, Washington.
authors: Megan
authors: M
authors: Parker
authors: Division of Human Nutrition, Wageningen University, Wageningen, The Netherlands.
authors: Sou Chheng
authors: SC
authors: Ly
authors: Department of Nutrition, Exercise and Sports, University of Copenhagen, Denmark.
authors: Henrik
authors: H
authors: Friis
authors: Department of Nutrition, Exercise and Sports, University of Copenhagen, Denmark.
authors: Nanna
authors: N
authors: Roos
authors: Institut de Recherche pour le Développement, Montpellier, France.
authors: Frank T
authors: FT
authors: Wieringa
mesh_terms: D000293:Adolescent; D018798:Anemia, Iron-Deficiency / Q000150:complications / Q000378:metabolism / Q000523:psychology*; D001196:Ascariasis / Q000150:complications / Q000378:metabolism / Q000523:psychology; D002160:Cambodia; D002648:Child; D003071:Cognition; D060825:Cognitive Dysfunction / Q000150:complications / Q000378:metabolism / Q000523:psychology*; D060085:Coinfection; D005260:Female; D005293:Ferritins / Q000378:metabolism*; D006454:Hemoglobins / Q000378:metabolism; D006725:Hookworm Infections / Q000150:complications / Q000378:metabolism / Q000523:psychology*; D006801:Humans; D007501:Iron / Q000378:metabolism*; D000090463:Iron Deficiencies; D016014:Linear Models; D008297:Male; D011990:Receptors, Transferrin / Q000378:metabolism*; D012720:Severity of Illness Index; D012923:Social Class; D013622:Taeniasis / Q000150:complications / Q000378:metabolism / Q000523:psychology; D014257:Trichuriasis / Q000150:complications / Q000378:metabolism / Q000523:psychology; D014801:Vitamin A / Q000378:metabolism; D015032:Zinc / Q000378:metabolism
chemical_list: D006454:Hemoglobins; D011990:Receptors, Transferrin; D014801:Vitamin A; D005293:Ferritins; D007501:Iron; D015032:Zinc