RESUMEN
BACKGROUND/OBJECTIVE: To assess the effectiveness of iron supplements administered to school children through a longitudinal school health intervention in terms of child haemoglobin concentration and anaemia prevalence. SUBJECTS/METHODS: Children and adolescents aged 5-17 years were selected from 30 schools in north-west Pakistan for a longitudinal iron supplement intervention. Children received once-weekly iron supplements (200 mg ferrous sulphate containing 63 mg of elemental iron) for 24 weeks (n=352); or the same supplements twice-weekly for 12 weeks (n=298) or received no tablets (n=298). Haemoglobin concentration was estimated in finger-prick blood samples at baseline, 12 and 24 weeks. Follow-up samples were taken at 36 weeks. RESULTS: A non-significant increase in haemoglobin concentration was observed in children receiving iron supplements after 12 weeks (mean 1.4 g/l s.d. 15.0 g/l in once-weekly versus 2.5 g/l s.d. 14.5 g/l in twice-weekly) compared with the group receiving no iron supplements. There was no significant reduction in the prevalence of anaemia in the once-weekly or twice-weekly group compared with the unsupplemented group. The prevalence of anaemia increased in all three groups during the follow-up period (24-36 weeks). CONCLUSIONS: Once-weekly and twice-weekly iron supplements were not associated with significant increases in haemoglobin concentration compared with unsupplemented children. In all groups, baseline haemoglobin concentration was the strongest predictor of haemoglobin increase. The lack of improvement may stem from the moderate baseline prevalence of anaemia (33%); other micronutrient deficiencies; variable compliance; or the worsening of haemoglobin status owing to seasonal changes in dietary iron and other nutrients.
Asunto(s)
Anemia Ferropénica/tratamiento farmacológico , Suplementos Dietéticos , Compuestos Ferrosos/uso terapéutico , Hemoglobinas/metabolismo , Hierro/uso terapéutico , Oligoelementos/uso terapéutico , Adolescente , Anemia Ferropénica/sangre , Niño , Preescolar , Esquema de Medicación , Femenino , Compuestos Ferrosos/administración & dosificación , Compuestos Ferrosos/farmacología , Humanos , Hierro/administración & dosificación , Hierro/farmacología , Hierro de la Dieta/administración & dosificación , Hierro de la Dieta/farmacología , Hierro de la Dieta/uso terapéutico , Estudios Longitudinales , Masculino , Pakistán , Servicios de Salud Escolar , Oligoelementos/administración & dosificación , Oligoelementos/farmacología , Resultado del TratamientoRESUMEN
OBJECTIVE: To report on the haemoglobin concentrations and prevalence of anaemia in schoolchildren in eight countries in Africa and Asia. DESIGN: Blood samples were collected during surveys of the health of schoolchildren as a part of programmes to develop school-based health services. SETTING: Rural schools in Ghana, Indonesia, Kenya, Malawi, Mali, Mozambique, Tanzania and Vietnam. SUBJECTS: Nearly 14 000 children enrolled in basic education in three age ranges (7-11 years, 12-14 years and > or =15 years) which reflect the new UNICEF/WHO thresholds to define anaemia. RESULTS: Anaemia was found to be a severe public health problem (defined as >40% anaemic) in five African countries for children aged 7-11 years and in four of the same countries for children aged 12-14 years. Anaemia was not a public health problem in the children studied in the two Asian countries. More boys than girls were anaemic, and children who enrolled late in school were more likely to be anaemic than children who enrolled closer to the correct age. The implications of the four new thresholds defining anaemia for school-age children are examined. CONCLUSIONS: Anaemia is a significant problem in schoolchildren in sub-Saharan Africa. School-based health services which provide treatments for simple conditions that cause blood loss, such as worms, followed by multiple micronutrient supplements including iron, have the potential to provide relief from a large burden of anaemia.