[Factors associated with the nutritional status of iodine in the maternal-infant group: a systematic review]. / Fatores associados ao estado nutricional de iodo no grupo materno-infantil: uma revisão sistemática.

This article sets out to identify the socio-demographic and nutritional factors associated with the nutritional status of iodine in the maternal-infant group. The review was based on the Prisma method and the Medline (PubMed), Scopus and Lilacs databases were consulted. The search was conducted in December 2018, using the key words nutritional status, iodine, infant, pregnant and lactating. The selection followed the stages of excluding duplicated articles, reading the titles, abstracts and texts in full. A total of 1,500 studies were identified and 26 met the inclusion criteria. The methodological quality of the studies was evaluated using the questionnaire proposed by Downs and Black. There was an association between the sociodemographic factors of income, education, maternal and gestational age, uniformity and place of residence in rural or urban areas with the nutritional state of iodine. In relation to dietary factors, the consumption of supplements, iodized salt and dietary sources of iodine, especially dairy products, play a protective role to avoid the deficiency. It is necessary to create more specific and effective strategies that address all the factors that affect the nutritional state of iodine to avoid the disorders resulting from the deficiency.

O objetivo deste artigo é identificar os fatores sociodemográficos e alimentares associados ao estado nutricional de iodo do grupo materno-infantil. A revisão foi baseada no método PRISMA. As bases consultadas foram: Medline (PubMed), Scopus e Lilacs. A busca ocorreu em dezembro de 2018, utilizando os descritores estado nutricional, iodo, lactente, gestante e lactante. A seleção seguiu as etapas de exclusão dos duplicados, leitura dos títulos, resumos e análise na íntegra. Foram identificados 1.500 estudos e 26 contemplaram os critérios de inclusão. A qualidade metodológica dos estudos foi avaliada pelo questionário proposto por Downs e Black. Houve associação entre os fatores sociodemográficos renda, escolaridade, idade materna e gestacional, paridade e local de residência rural ou urbano com o estado nutricional de iodo. Já em relação aos fatores alimentares, o consumo de suplementos, sal iodado e alimentos fontes de iodo, em especial os produtos lácteos, exercem papel protetor contra a deficiência. É preciso criar estratégias mais específicas, efetivas e que contemplem todos esses fatores que afetam o estado nutricional de iodo para evitar as desordens provocadas pela deficiência.

Fatores associados ao estado nutricional de iodo no grupo materno-infantil: uma revisão sistemática / Factors associated with the nutritional status of iodine in the maternal-infant group: a systematic review

Resumo O objetivo deste artigo é identificar os fatores sociodemográficos e alimentares associados ao estado nutricional de iodo do grupo materno-infantil. A revisão foi baseada no método PRISMA. As bases consultadas foram: Medline (PubMed), Scopus e Lilacs. A busca ocorreu em dezembro de 2018, utilizando os descritores estado nutricional, iodo, lactente, gestante e lactante. A seleção seguiu as etapas de exclusão dos duplicados, leitura dos títulos, resumos e análise na íntegra. Foram identificados 1.500 estudos e 26 contemplaram os critérios de inclusão. A qualidade metodológica dos estudos foi avaliada pelo questionário proposto por Downs e Black. Houve associação entre os fatores sociodemográficos renda, escolaridade, idade materna e gestacional, paridade e local de residência rural ou urbano com o estado nutricional de iodo. Já em relação aos fatores alimentares, o consumo de suplementos, sal iodado e alimentos fontes de iodo, em especial os produtos lácteos, exercem papel protetor contra a deficiência. É preciso criar estratégias mais específicas, efetivas e que contemplem todos esses fatores que afetam o estado nutricional de iodo para evitar as desordens provocadas pela deficiência.

Abstract This article sets out to identify the socio-demographic and nutritional factors associated with the nutritional status of iodine in the maternal-infant group. The review was based on the Prisma method and the Medline (PubMed), Scopus and Lilacs databases were consulted. The search was conducted in December 2018, using the key words nutritional status, iodine, infant, pregnant and lactating. The selection followed the stages of excluding duplicated articles, reading the titles, abstracts and texts in full. A total of 1,500 studies were identified and 26 met the inclusion criteria. The methodological quality of the studies was evaluated using the questionnaire proposed by Downs and Black. There was an association between the sociodemographic factors of income, education, maternal and gestational age, uniformity and place of residence in rural or urban areas with the nutritional state of iodine. In relation to dietary factors, the consumption of supplements, iodized salt and dietary sources of iodine, especially dairy products, play a protective role to avoid the deficiency. It is necessary to create more specific and effective strategies that address all the factors that affect the nutritional state of iodine to avoid the disorders resulting from the deficiency.

Ingestion of supplements and fortified food with iodine on the breast milk iodine concentration in deficiency areas: a systematic review.

INTRODUCTION: The level of iodine in breast milk may be inadequate and compromise the health of this, both due to excess and lack, some population groups remain deficient because of the low consumption of iodate salt, because there is an increase in consumption of other sources of iodine, such as supplements and fortified foods. OBJECTIVE: To evaluate the effect of the consumption of fortified foods and nutritional supplements with iodine on maternal milk levels. METHODOLOGY: Systematic review based on the Prism method, using the descriptors provided by DeCS. The reading, selection and analysis of the methodological quality of the articles was done by two researchers independently. RESULTS: From 346 abstracts, 6 were eligible. The median iodination range between the studies ranged from 75 to 600 µg in supplements and 150 and 225 µg in fortified foods with effect on increased iodine concentration of breastmilk (BMIC), achieving the adequacy of the median BMIC in 4 of the 6 studies. CONCLUSION: Iodine ingestion through supplements or fortified foods results in improved iodine levels in breast milk.

Micronutrient supplementation adherence and influence on the prevalences of anemia and iron, zinc and vitamin A deficiencies in preemies with a corrected age of six months.

OBJECTIVE: To analyze adherence to the recommended iron, zinc and multivitamin supplementation guidelines for preemies, the factors associated with this adherence, and the influence of adherence on the occurrence of anemia and iron, zinc and vitamin A deficiencies. METHODS: This prospective cohort study followed 58 preemies born in 2014 until they reached six months corrected age. The preemies were followed at a referral secondary health service and represented 63.7% of the preterm infants born that year. Outcomes of interest included high or low adherence to iron, zinc and multivitamin supplementation guidelines; prevalence of anemia; and prevalences of iron, zinc, and vitamin A deficiencies. The prevalence ratios were calculated by Poisson regression. RESULTS: Thirty-eight (65.5%) preemies presented high adherence to micronutrient supplementation guidelines. At six months of corrected age, no preemie had vitamin A deficiency. The prevalences of anemia, iron deficiency and zinc deficiency were higher in the low-adherence group but also concerning in the high-adherence group. Preemies with low adherence to micronutrient supplementation guidelines were 2.5 times more likely to develop anemia and 3.1 times more likely to develop zinc deficiency. Low maternal education level increased the likelihood of nonadherence to all three supplements by 2.2 times. CONCLUSIONS: Low maternal education level was independently associated with low adherence to iron, zinc and vitamin A supplementation guidelines in preemies, which impacted the prevalences of anemia and iron and zinc deficiencies at six months of corrected age.

Micronutrient supplementation adherence and influence on the prevalences of anemia and iron, zinc and vitamin A deficiencies in preemies with a corrected age of six months

OBJECTIVE: To analyze adherence to the recommended iron, zinc and multivitamin supplementation guidelines for preemies, the factors associated with this adherence, and the influence of adherence on the occurrence of anemia and iron, zinc and vitamin A deficiencies. METHODS: This prospective cohort study followed 58 preemies born in 2014 until they reached six months corrected age. The preemies were followed at a referral secondary health service and represented 63.7% of the preterm infants born that year. Outcomes of interest included high or low adherence to iron, zinc and multivitamin supplementation guidelines; prevalence of anemia; and prevalences of iron, zinc, and vitamin A deficiencies. The prevalence ratios were calculated by Poisson regression. RESULTS: Thirty-eight (65.5%) preemies presented high adherence to micronutrient supplementation guidelines. At six months of corrected age, no preemie had vitamin A deficiency. The prevalences of anemia, iron deficiency and zinc deficiency were higher in the low-adherence group but also concerning in the high-adherence group. Preemies with low adherence to micronutrient supplementation guidelines were 2.5 times more likely to develop anemia and 3.1 times more likely to develop zinc deficiency. Low maternal education level increased the likelihood of nonadherence to all three supplements by 2.2 times. CONCLUSIONS: Low maternal education level was independently associated with low adherence to iron, zinc and vitamin A supplementation guidelines in preemies, which impacted the prevalences of anemia and iron and zinc deficiencies at six months of corrected age.

Anemia in Brazilian pregnant women before and after flour fortification with iron.

OBJECTIVE: To compare prevalence of anemia and hemoglobin (Hb) levels in Brazilian pregnant women before and after flour fortification with iron. METHODS: A repeated cross-sectional panel study of public health care centers of municipalities in the five Brazilian regions was conducted. Retrospective data were obtained from 12,119 medical records of pregnant women distributed in two groups: before fortification (delivery prior to June 2004) and after fortification (date of last period after June 2005). Anemia was defined as Hb<11.0 g/dl. Hb levels according to gestational age were assessed using two references from the literature. Statistical analysis was carried out using chi-squared tests, Student's t tests, and logistic regression, with a significance level of 5%. RESULTS: In the total sample, prevalence of anemia fell from 25% to 20% after fortification (p<0.001). However, important regional differences were evident: while significant reductions were seen in the Northeast (37% to 29%) and North (32% to 25%) regions, where pre-fortification prevalence was high, smaller reductions were seen in the Southeast (18% to 15%) and South (7% to 6%) regions, where prevalence was low. Hb levels according to gestational age were slightly higher in the first months of pregnancy and lower after the third or fourth months, depending on the reference used. Logistic regression analysis showed that group, geographic region, marital status, trimester of pregnancy, initial nutritional status, and prior pregnancy were associated with anemia (p<0.05). CONCLUSIONS: Prevalence of anemia decreased after fortification, but remains high in the North and Northeast regions. Although fortification may have played a role in this favorable outcome, the contribution of other public policies implemented during the studied period should also be considered.

Anemia em gestantes brasileiras antes e após a fortificação das farinhas com ferro / Anemia in Brazilian pregnant women before and after flour fortification with iron / Anemia en gestantes brasileñas antes y después de la fortificación de harinas con hierro

OBJETIVO: Comparar prevalência de anemia e valores de hemoglobina (Hb) em gestantes brasileiras, antes e após a fortificação das farinhas com ferro. MÉTODOS: Estudo de avaliação de painéis repetidos, desenvolvido em serviços públicos de saúde de municípios das cinco regiões brasileiras. Dados retrospectivos foram obtidos de 12.119 prontuários de gestantes distribuídas em dois grupos: antes da fortificação, com parto anterior a junho de 2004, e após a fortificação, com última menstruação após junho de 2005. Anemia foi definida como Hb < 11,0 g/dL. Valores de Hb/idade gestacional foram avaliados segundo dois referenciais da literatura. Foram utilizados teste qui-quadrado, t de Student e regressão logística, com nível de 5 por cento de significância. RESULTADOS: Na amostra total, anemia caiu de 25 por cento para 20 por cento após fortificação (p < 0,001), com médias de Hb significativamente maiores no grupo "após" (p < 0,001). Observaram-se, entretanto, diferenças regionais importantes: reduções significativas nas regiões Nordeste (37 por cento para 29 por cento) e Norte (32 por cento para 25 por cento), onde as prevalências de anemia eram elevadas antes da fortificação, e reduções menores nas regiões Sudeste (18 por cento para 15 por cento) e Sul (7 por cento para 6 por cento), onde as prevalências eram baixas. Os níveis de Hb/idade gestacional de ambos os grupos se mostraram discretamente mais elevados nos primeiros meses, porém bem mais baixos após o terceiro ou quarto mês, dependendo da referência utilizada para comparação. Análise de regressão logística mostrou que grupo, região geográfica, situação conjugal, trimestre gestacional, estado nutricional inicial e gestação anterior associaram-se com anemia (p < 0,05). CONCLUSÕES: A prevalência de anemia diminuiu após a fortificação, porém continua elevada nas regiões Nordeste e Norte. Embora a fortificação possa ter tido papel nesse resultado favorável, há que se considerar a contribuição de outras políticas públicas implementadas no período estudado.

OBJECTIVE: To compare prevalence of anemia and hemoglobin (Hb) levels in Brazilian pregnant women before and after flour fortification with iron. METHODS: A repeated cross-sectional panel study of public health care centers of municipalities in the five Brazilian regions was conducted. Retrospective data were obtained from 12,119 medical records of pregnant women distributed in two groups: before fortification (delivery prior to June 2004) and after fortification (date of last period after June 2005). Anemia was defined as Hb<11.0 g/dl. Hb levels according to gestational age were assessed using two references from the literature. Statistical analysis was carried out using chi-squared tests, Student's t tests, and logistic regression, with a significance level of 5 percent. RESULTS: In the total sample, prevalence of anemia fell from 25 percent to 20 percent after fortification (p<0.001). However, important regional differences were evident: while significant reductions were seen in the Northeast (37 percent to 29 percent) and North (32 percent to 25 percent) regions, where pre-fortification prevalence was high, smaller reductions were seen in the Southeast (18 percent to 15 percent) and South (7 percent to 6 percent) regions, where prevalence was low. Hb levels according to gestational age were slightly higher in the first months of pregnancy and lower after the third or fourth months, depending on the reference used. Logistic regression analysis showed that group, geographic region, marital status, trimester of pregnancy, initial nutritional status, and prior pregnancy were associated with anemia (p<0.05). CONCLUSIONS: Prevalence of anemia decreased after fortification, but remains high in the North and Northeast regions. Although fortification may have played a role in this favorable outcome, the contribution of other public policies implemented during the studied period should also be considered.

OBJETIVO: Comparar prevalencia de anemia y valores de hemoglobina (Hb) en gestantes brasileñas, antes y después de la fortificación de las harinas con hierro. MÉTODOS: Estudio de evaluación de paneles repetidos, desarrollado en servicios públicos de salud de municipios de las cinco regiones brasileñas. Datos retrospectivos se obtuvieron de 12.119 prontuarios de gestantes distribuidas en dos grupos: antes de la fortificación, con parto anterior a junio de 2004, y posterior a la fortificación, con última menstruación después de junio 2005. Anemia fue definida como Hb<11,0 g/dL. Valores de Hb/edad gestacional fueron evaluados según dos referenciales de la literatura. Se utilizaron prueba de chi-cuadrado, t de Student y regresión logística, con nivel de 5 por ciento de significancia. RESULTADOS: En la muestra total, anemia disminuyó de 25 por ciento a 20 por ciento después de la fortificación (p<0,001), con promedios de Hb significativamente mayores en el grupo "posterior" (p<0,001). Se observaron, sin embargo, diferencias regionales importantes: reducciones significativas en las regiones Noreste (de 37 por ciento a 29 por ciento) y Norte (de 32 por ciento a 25 por ciento), donde las prevalencias de anemia eran elevadas antes de la fortificación; y reducciones menores en las regiones Sureste (de 18 por ciento a 15 por ciento) y Sur (de 7 por ciento a 6 por ciento), donde las prevalencias eran bajas. Los niveles de Hb/edad gestacional de ambos grupos se mostraron discretamente mas elevados en los primeros meses, aunque mucho mas bajos posterior al tercero o cuarto mes, dependiendo de la referencia utilizada para comparación. Análisis de regresión logística mostró cual grupo, región geográfica, situación conyugal, trimestre gestacional, estado nutricional inicial y gestación anterior se asociaron con anemia (p<0,05). CONCLUSIONES: La prevalencia de anemia disminuyó posterior a la fortificación, aunque continua elevada en las regiones Noreste y Norte. A pesar de que la fortificación pueda haber tenido papel en este resultado favorable, hay que considerar la contribución de otras políticas públicas implementadas en el periodo estudiado.

Interação entre vitamina A e ferro em diferentes grupos populacionais / Vitamin A and iron interaction in different populations

A interação entre ferro e vitamina A tem sido alvo de pesquisas científicas, visto que existem questões ainda pouco esclarecidas. Através de um levantamento bibliográfico, mediante consulta à base de dados Medline da National Library of Medicine, EUA, foram selecionadas publicações que tratavam sobre a interação entre ferro e vitamina A em seres humanos, a partir da década de 80 até o ano de 2003. As palavras chave utilizadas no levantamento bibliográfico foram "ferro", "vitamina A" e "anemia" e seus correspondentes em língua inglesa. Os resultados indicam que existe correlação entre os indicadores do estado nutricional de vitamina A e ferro em crianças, adolescentes e gestantes e que a fortificação e suplementação com vitamina A têm efeito favorável no metabolismo do ferro nesses grupos. Entretanto, ainda são necessários mais estudos para se conseguir estabelecer quais as doses e o período necessário de suplementação de vitamina A para beneficiar significantemente o estado nutricional de ferro. Os mecanismos que explicam a associação entre vitamina A e ferro ainda são desconhecidos, entretanto alguns autores atribuem essa interação ao fato de a vitamina A beneficiar a eritropoese, prevenir infecções ou melhorar a absorção de ferro.

Interaction between iron and vitamin A has been the focus of scientific research for the reason that some of the issues still remain unknown. A literature review through Medline of the National Library of Medicine, USA, database selected scientific publications addressing interaction of iron and vitamin A in humans beginning in the 80's and proceeding to the year of 2003. The key words used in the literature review were "iron", "vitamin A" and "anemia" and corresponding terminology in Portuguese. Results indicates a correlation between vitamin A and iron nutritional indicators in children, adolescents, and pregnant women establishing also that vitamin A fortification and supplementation has a favorable effect on the iron metabolism of these populations. Further studies are required to establish dosages and time of vitamin A supplementation necessary to significantly benefit the iron nutritional status. Mechanisms explaining the association of vitamin A and iron are still ignored, however it is the understanding of some authors that this interaction results from the fact that vitamin A benefits erythropoiesis, prevents infections and improves iron absorption.