Relationships between vitamin A, iron status and helminthiasis in Bangladeshi school children

Abstract

Objective: To explore the relationships between biochemical indicators of vitamin A and iron status and the intestinal helminthsAscaris lumbricoidesand hookworm in primary school children.Setting: Two rural governmental schools in northwestern Bangladesh.Design: Cross-sectional study.Subjects: The sample consisted of 164 children in grades 3–5.Methods: Serum retinol and β-carotene (by high-performance liquid chromatography, HPLC), haemoglobin (HemoCue), ferritin (enzyme-linked immunoadsorbent assay, ELIZA) and height and weight were measured. Dietary intake of vitamin A was assessed using a food frequency questionnaire and faecal analyses were done using Stoll's egg-count technique.Results: The mean serum retinol was 26.8 μg dl⁻¹and 20% had a level of −1, the cut-off value for low vitamin A status. There was a strong positive association between serum β-carotene and serum retinol (r= 0.44,P−1), 30% had iron deficiency (serum ferritin −1) and 14% were suffering from iron deficiency anaemia. Children with a serum retinol level of 20 μg dl⁻¹had significantly lower ferritin (14.0 compared to 26.0 μg l⁻¹,P= 0.005) and Hb levels (11.7 compared to 12.4 g dl⁻¹,P= 0.005) than those with higher levels. The proportion of iron deficiency anaemia was significantly greater among children with hookworm. Our data suggest that hookworm exerts its impact on iron status independently of the vitamin A status of the host.Conclusions: Programmes to improve iron status should consider including both vitamin A prevention programmes and deworming.