RESUMO
OBJECTIVE: To evaluate body composition changes using bioelectrical impedance analysis and skinfold thickness measurements in infants from tropical areas who become stunted between 4-18 months of age. DESIGN AND MEASUREMENTS: Follow-up study. Extracellular water to total body water ratio index (length(2)/resistance at low to high frequency), peripheral fat (tricipital and subscapular skinfold thickness), and length-for-age index were studied at 4 and 18 months of age. SETTINGS: Low-income areas in four tropical regions (Congo, Senegal, Bolivia and New Caledonia). SUBJECTS: Infants were included in the analysis provided they were neither stunted nor wasted at 4 months. Two groups of infants were compared, those that were stunted at 18 months (n=61) or not (n=170). RESULTS: The extracellular water to total body water ratio index and the sum of skinfold thickness measurements were similar in the two groups at 4 months, and only the extracellular water to total body water ratio index was significantly different at 18 months. When no stunting appeared between 4 and 18 months, the change in the extracellular water to total body water ratio index was not linked with variations in length-for-age, and presented the expected pattern of variation in body water compartments. When stunting occurred, variation in length-for-age was related to significant changes in the extracellular water to total body water ratio index, the biggest increase in the proportion of extracellular water being found in the most stunted infants. Variations in the sum of the two skinfold thickness measurements presented the expected pattern for the 4-18 months growth and did not differ between the two groups. CONCLUSIONS: Multifrequency resistances suggested that stunting was associated with a lack of the expansion of the intracellular compartment that is expected during normal growth of cell mass, together with preserved fat mass. SPONSORSHIPS: Supported by grant 92L0623 from the French Ministry of Research, and by Institut de Recherche pour le Développement (IRD).
Assuntos
Água Corporal/fisiologia , Transtornos do Crescimento/fisiopatologia , Tecido Adiposo/fisiologia , África , Fatores Etários , Estatura/fisiologia , Peso Corporal/fisiologia , Bolívia , Impedância Elétrica , Líquido Extracelular/fisiologia , Seguimentos , Humanos , Lactente , Nova Caledônia , Pobreza , Dobras CutâneasRESUMO
OBJECTIVE: To compare the efficacy of a daily and a weekly iron supplementation on the hematological status of anemic children living at high altitude. DESIGN: Double blind iron supplementation trial including a placebo control group. SETTING: A socioeconomically disadvantaged district of La Paz, Bolivia (altitude of 4000 m). SUBJECTS: Anemic (hemoglobin concentration < or = 144 g/L), 3.3-8.3 y old children of both sexes. INTERVENTION: Children received a placebo (n = 57) or a dose of 3-4 mg of elemental iron per kg body weight (FeSO4 tablets) 1 d per week (n = 58) or 5 d per week (n = 58) for 16 weeks. RESULTS: Hemoglobin and zinc erythrocyte protoporphyrin concentrations improved significantly in supplemented groups but not in the placebo group. Changes in hemoglobin during the study were not significantly different between supplemented groups (weekly group: 15.2 +/- 6.9 g/L and daily group: 18.6 +/- 11.1 g/L) but were different from the placebo group (0.5 +/- 7.1 g/L, P < 0.001). At the end of the supplementation period, the hemoglobin distribution was Gaussian, and similar in both supplemented groups. Adjusting for the initial hemoglobin concentration, final hemoglobin and its changes were similar in both supplemented groups. CONCLUSION: Weekly iron supplementation is as efficacious as daily iron supplementation in improving iron status and correcting moderate iron deficiency anemia in Bolivian school children living at high altitude. SPONSORSHIP: Program supported in part by ORSTROM, the French Ministry of Foreign Affairs and the National Secretary's Office of Health, Bolivia.
Assuntos
Altitude , Ferro/administração & dosagem , Anemia Ferropriva/tratamento farmacológico , Anemia Ferropriva/prevenção & controle , Bolívia , Criança , Pré-Escolar , Método Duplo-Cego , Eritrócitos/química , Feminino , Hemoglobinas/metabolismo , Humanos , Masculino , Placebos , Protoporfirinas/sangue , Zinco/sangueRESUMO
This paper discusses the effect that high altitudes have on iron metabolism and summarizes the results of an iron-folate supplementation trial. The two main objectives of the trial were to determine hemoglobin cut-off values for the diagnosis of anemia in Bolivian women of childbearing age living at high altitudes, and to estimate the prevalence of anemia in this population. The study showed that nutritional anemia is an important public health problem in such populations and that many methods of assessing it lead to an underestimation of prevalence. The cut-off values defined through this study, one of the few iron supplementation trials conducted at high altitudes, confirm the need to establish revised hemoglobin values for the diagnosis of anemia in populations living at high altitudes.
Assuntos
Altitude , Anemia Ferropriva/tratamento farmacológico , Anemia Ferropriva/epidemiologia , Ácido Fólico/uso terapêutico , Ferro/uso terapêutico , Adolescente , Adulto , Envelhecimento/sangue , Anemia Ferropriva/diagnóstico , Antropometria , Bolívia/epidemiologia , Feminino , Ácido Fólico/administração & dosagem , Ácido Fólico/sangue , Alimentos Fortificados , Hemoglobinas/análise , Humanos , Ferro/administração & dosagem , Ferro/sangue , Modelos Lineares , Estado Nutricional , Prevalência , Saúde PúblicaRESUMO
The effect of supplementation on growth was tested by means of four similar controlled randomized trials in the Congo (n = 120), Senegal (n = 110), Bolivia (n = 127), and New Caledonia (n = 90). Four-month-old infants were randomly allocated to supplement or control groups. A cereal-based precooked porridge was offered twice daily for 3 mo and consumption was monitored. Both groups were free to eat local food. At 7 mo of age, all infants were still breast-fed in the Congo, Senegal, and Bolivia compared with 47% in New Caledonia. Mean daily consumption of the supplement varied among countries (558-790 kJ/d). Mean length at 4 mo was lowest in Bolivia, higher in Senegal and the Congo, and near the National Center for Health Statistics reference in New Caledonia. The mean 4-7 mo length increment was 0.48 cm higher for supplemented than for control infants in Senegal (P < 0.05), whereas weight increments did not differ. No significant effect was found in the other countries.
PIP: Findings from this study of the link between nutritional supplementation during breast feeding and infant growth disagree with earlier studies. The effect of nutritional supplementation on growth in length was only modest, but significant only in Senegal and not significant in the Congo, Bolivia, and New Caledonia. It is hypothesized that food supplementation during the 4-7 month period would have a positive effect on linear growth. This study included four controlled randomized trials among 120 infants in the Congo, 110 infants in Senegal, 127 infants in Bolivia, and 90 infants in New Caledonia. The infants were 4 months old when placed in the supplement or control groups. Supplementation included the addition of a cereal-based precooked porridge twice daily for 3 months. Both groups continued to eat local foods. Breast feeding patterns were different in New Caledonia, where only 47% of infants were still breast fed at 7 months of age. Mean daily supplementation varied among countries, from 558 to 790 kJ/day. Mean length was lowest in Bolivia, higher in Senegal and the Congo, and close to the US National Center for Health Statistics reference measures in New Caledonia. The study was conducted in rural parts of Senegal and New Caledonia and periurban parts of Bolivia and the Congo. Supplementation was supervised by field workers. The samples included infants with a length-for-age score of -2.5 or higher and a weight-for-length Z score of -2 or higher at 4 months. Anthropometric measurements were taken at 4 months and 4, 8, and 13 weeks later (at 4.9, 5.8, and 7.0 months of age). 24-hour food recalls were collected monthly for consumption of breast milk, special local infant food, commercial "western" baby food, milk substitutes, family food, water, and other than milk liquids.