Malaria is causally associated with iron deficiency in African children

Abstract

Objectives: Malaria and iron deficiency (ID) are common causes of ill health in African children. Recent evidence shows that malaria increases production of the hormone hepcidin which blocks iron absorption. We therefore aimed to determine whether malaria causes ID in African children by conducting a well-designed genetic study called Mendelian randomization. Methods: We used sickle cell trait (HbAS), a common genetic variant that is associated with partial protection against malaria. We measured markers of iron status and inflammation and genotyped HbAS in 6862 African children from eight community cohorts in Kenya, Burkina Faso, Uganda, The Gambia, South Africa, Congo and Cameroon. We further tested whether HbAS influences ID in the absence of malaria using a malaria-free cohort of African-Americans. Results: Among children exposed to malaria, HbAS was associated with a 23% reduction in ID. This translated to malaria causing a 55% increase in ID. HbAS was not associated with other factors that may influence malaria/ID or with ID in African-Americans suggesting that the observed increase in ID was indeed due to malaria. Conclusions: These results suggest that malaria may be an important cause of ID in African children. Therefore, efforts towards malaria elimination may have an added advantage of reducing the burden of ID.