Acessibilidade / Reportar erro

IRON DEFICIENCY ANEMIA AND ITS RELATIONSHIP WITH SOCIOECONOMIC VULNERABILITY

ABSTRACT

Objective:

To analyze the association of anemia with the socioeconomic vulnerability of preschoolers in public day care centers, in the city of Taubaté, SP, Brazil.

Methods:

This is a cross-sectional study with a probabilistic sample that analyzed 363 children assisted in public day care centres in low-income and high-income areas of Taubaté, SP, Brazil. The hemoglobin concentration (Hb), dependent variable, was obtained by digital puncture, considering anemic children with Hb concentration <11.0 g/dL. The independent variables such as socioeconomic and demographic conditions were collected by a semi-structured questionnaire.

Results:

The prevalence of iron deficiency anemia was 19.3% among preschoolers. Children from day care centers with high socioeconomic vulnerability had lower Hb concentration than those from a non-vulnerable area (p<0.05).

Conclusions:

The lower concentration of hemoglobin in preschoolers is associated with the location of day care centers in an area of socioeconomic vulnerability. Children attending these day care centers face adverse family conditions such as low income, working mothers, and mothers with low schooling, though they receive social benefits and monitoring by public health services.

Keywords:
Anemia, iron-deficiency; Child, preschool; Health status disparities; Health vulnerability; Child

RESUMO

Objetivo:

Analisar a associação da anemia com a vulnerabilidade socioeconômica de pré-escolares de creches públicas da cidade de Taubaté, SP, Brasil.

Métodos:

Trata-se de um estudo transversal com amostra probabilística que analisou 363 crianças assistidas em creches públicas de regiões de baixa e alta renda de Taubaté. A concentração de hemoglobina (Hb), variável dependente, foi obtida por meio de punção digital, considerando anêmicas as crianças com concentração de Hb<11,0 g/dL. As variáveis independentes como condições socioeconômicas e demográficas foram coletadas por questionário semiestruturado.

Resultados:

A prevalência de anemia por deficiência de ferro foi de 19,3% entre os pré-escolares. As crianças das creches de elevada vulnerabilidade socioeconômica apresentaram concentração de Hb estatisticamente menor do que aquelas de região não vulnerável (p<0,05).

Conclusões:

A menor concentração de Hb em pré-escolares está associada à localização das creches em região de vulnerabilidade socioeconômica, uma vez que as crianças que frequentam tais creches enfrentam condições adversas familiares, como baixa renda, mães que trabalham e com baixa escolaridade, embora recebam benefício social e acompanhamento pelos serviços públicos de saúde.

Palavras-chave:
Anemia ferropriva; Pré-escolares; Desigualdades em saúde; Vulnerabilidade em saúde; Criança

INTRODUCTION

Iron deficiency anemia in children under five years of age stands out among specific nutritional deficiencies, with a prevalence of 42.6%, affecting 273.2 million children worldwide. Its deleterious consequences, which are often irreversible in adulthood, include a population that is physically disabled and not prepared for the labor market, often being socially excluded.11. World Health Organization [homepage on the Internet]. The global prevalence of anaemia in 2011. Geneva: WHO; 2015 [cited 2016 Dec 10]. Available from: Available from: http://www.who.int/nutrition/publications/micronutrients/global_prevalence_anaemia_2011/en/
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,22. Haas JD, Brownlie T 4th. Iron deficiency and reduced work capacity: a critical review of the research to determine a causal relationship. J Nutr. 2001;131:676S-88S. https://doi.org/10.1093/jn/131.2.676S
https://doi.org/https://doi.org/10.1093/...
,33. Grantham-McGregor S, Ani C. A review of studies on the effect of iron deficiency on cognitive development in children. J Nutr. 2001;131:649S-66S. https://doi.org/10.1093/jn/131.2.649S
https://doi.org/https://doi.org/10.1093/...

It is noteworthy that Brazilian preschoolers and women of reproductive age, the populations that are most sensitive to anemia, continue to show high prevalence of this nutritional deficiency despite interventions for flour fortification and iron supplementation, which were implemented over a decade ago.44. Brazil - Ministério da Saúde. Agência Nacional de Vigilância Sanitária. Resolução RDC n° 344, de 13 de dezembro de 2002. Aprova o Regulamento Técnico para a fortificação das farinhas de trigo e das farinhas de milho com ferro e ácido fólico. Brasília (DF): Diário Oficial da União; 2002.,55. Brazil - Ministério da Saúde. Portaria nº 730, de 13 de maio de 2005, institui o Programa Nacional de Suplementação de Ferro. Brasília: Diário Oficial da União; 2005. This statement is confirmed by the high prevalence of anemia described in the National Demography and Health Survey in 2006, which identified anemia in 20.9% of Brazilian children and 29.4% of Brazilian women, representing a moderate risk situation in public health.66. Brazil - Ministério da Saúde. Pesquisa Nacional de Demografia e Saúde da Criança e da Mulher - PNDS 2006: dimensões do processo reprodutivo e da saúde da criança. Brasília: Ministério da Saúde; 2009.

In this sense, children, being dependent on the environment and susceptible to psychological, socioeconomic and cultural changes, are part of the most significantly relevant group, since their resilience to different vulnerability scenarios is investigated to understand various public health problems. In this way, the situations of social inequity and inequality, expressed through potential for illness, or non-illness,77. Silva IC, Restrepo-Mendez MC, Costa JC, Ewerling F, Hellwig F, Ferreira LZ, et al. Measurement of social inequalities in health: concepts and methodological approaches in the Brazilian context. Epidemiol Serv Saúde. 2018;27:e000100017. http://dx.doi.org/10.5123/s1679-49742018000100017
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overcome the probabilistic character of risk by pointing out a set of aspects that go beyond the individual, covering collective aspects of biological, psychological, cultural, economic and political order, which lead to susceptibility to diseases or injuries.88. Sanches AI, Bertolozzi MR. Can the vulnerability concept support the construction of knowledge in collective health care? Ciênc Saúde Coletiva. 2007;12:319-24. http://dx.doi.org/10.1590/S1413-81232007000200007
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The dietary deficiency in sources of iron is the major determinant of anemia, but iron deficiency has its origin in a broad context strongly linked to socioeconomic and cultural factors. Developing countries are marked by adverse social conditions and inefficient public policies that cause health inequities and, therefore, translate into different risks for the disease, causing unnecessary suffering to the population.99. Organização Mundial de Saúde. Diminuindo diferenças: a prática das políticas sobre determinantes sociais da saúde: documento de discussão. Geneva: OMS; 2011.

Thus, the recognition of health needs of individuals and families from different social groups is of great importance in identifying the profiles of social reproduction and health-disease, allowing the control and monitoring of public health,1010. Nakamura E, Egry EY, Campos CM, Nichiata LY, Chiesa AM, Takahashi RF. The potential of an instrument to identify social vulnerabilities and health needs: collective health knowledge and practices. Rev Latino-Am Enfermagem. 2009;17:253-8. http://dx.doi.org/10.1590/S0104-11692009000200018
https://doi.org/http://dx.doi.org/10.159...
especially when it involves nutritional problems among children, an issue that high, middle and low income countries alike are facing. Therefore, this article aimed to analyze the association of anemia with the socioeconomic vulnerability of preschoolers in public day care centers in a city in the Paraíba Valley, São Paulo, Brazil.

METHOD

Cross-sectional study with preschoolers aged 24 to 48 months who attended municipal day care centers in Taubaté, São Paulo, in 2014. Taubaté is located in the metropolitan region of the Paraíba Valley and on the state’s North Coast, 123 km from the city of Sao Paulo. It has a high human development index (HDI), being among the 40 best municipal HDIs in the country. This is justified by the gross domestic product (GDP) per capita, which in 2011 was one of the highest among those described for the São Paulo municipalities. This is in addition to the good basic sanitation indicators, the high percentage of public educational coverage and the various Family Health Strategy (FHS) teams, as well as the traditional basic health units with high population coverage distributed throughout the municipality.

Based on the Occupation, Income and Education Survey, the city of Taubaté was divided into five regions1111. Prado AL. A desigualdade e a distribuição da renda na cidade de Taubaté [undergraduate thesis]. Taubaté (SP): Universidade de Taubaté; 2007. and subsequently grouped into two socioeconomically distinct groups: vulnerable region, with an average family income of 1.35 minimum wages (class E); and non-vulnerable region, with average family income between 2.8 and 11.3 minimum wages (classes A, B, C and D). The sample size was calculated based on the assumption that the difference in hemoglobin concentration (Hb) between children in the vulnerable and non-vulnerable regions was equivalent to 1/3 standard deviation from the average Hb of the healthy population. Adopting α=5% and β=20%, at least 145 children would be needed for each region. Considering the 20% increase for eventual losses, the final sample was estimated at 350 children. The sampling was probabilistic, with successive random draws of day care centers in the two regions until the total sample was completed.

Regardless of the region where the day care centers are located, there are two types of pre-school care regime in the municipality, part-time and full-time. Students enrolled in the part-time program receive two meals a day at the day care center: preschoolers in the morning period were offered breakfast and lunch; and those in the afternoon period were offered an afternoon snack and dinner. For children who stayed full-time, four complete meals were offered: breakfast, lunch, afternoon snack and dinner. It is worth noting that the menu was planned in the same way for all public day care centers in the municipality, in accordance with the rules of the Department of Education of the City of Taubaté, being carried out daily in a proper environment inside the day care center facilities.

The diagnosis of anemia was made by measuring the Hb concentration. A capillary blood sample was obtained by puncture with a disposable lancet, puncturing it in the fingertip pulp of the middle or ring finger of the child’s left hand. For the measurement of Hb, the second drop of blood was collected by means of a fixed-volume micropipette, totalling 0.1 ml of blood, which was then added to 1.5 ml of Drabkins solution in an appropriate tube, with direct reading on the portable hemoglobinometer Agabe® (validated by Exa-M Instrumentação Biomédica LTDA., Mogi das Cruzes, SP, Brazil) by the cyanomethaemoglobin method. Before blood collection, parents/guardians were asked about the presence of genetic hemoglobinopathies in their children, with no notifications regarding this item. Children who showed infection or inflammation did not participate in the research while they were ill. Anemia was defined by the concentration of Hb <11.0 g/dL for children under five years of age.11. World Health Organization [homepage on the Internet]. The global prevalence of anaemia in 2011. Geneva: WHO; 2015 [cited 2016 Dec 10]. Available from: Available from: http://www.who.int/nutrition/publications/micronutrients/global_prevalence_anaemia_2011/en/
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Through a questionnaire, demographic and socioeconomic information were obtained: sex, age, child’s weight at birth, maternal schooling and occupation, family income, participation in social programs, inclusion of the family in the FHS and use of iron supplementation offered by the National Program of Iron Supplementation.

Statistical analyzes were performed using the Statistical Package for the Social Sciences (SPSS) software, version 20.0 for Windows (IBM, New York, United States). The Kolmogorov-Smirnov test was used to verify the normality of continuous variables. Initially, the high and low vulnerability regions were characterized using the χ2 test and the medians for Hb concentration were calculated using the Mann-Whitney test, as well as contingency tables for anemia prevalence.

Next, multiple regression analysis was carried out. The concentration of Hb was identified as a dependent variable, and the independent variable was the region of the day care center being defined by the child’s vulnerability and demographic conditions, and by the family’s socioeconomic conditions. The variables that presented p<0.20 in the univariate analysis were included in the multiple modeling process, considering associations with p<0.05 as significant in the regression model.

The research was approved by the Research Ethics Committee of the School of Public Health of Universidade de São Paulo (CEP/FSP - USP), no. 773.287, according to ethical standards. The guardians of the children authorized data collection by signing the informed consent. Children diagnosed with anemia were referred to the Pediatric Clinic of the University Hospital of Taubaté for proper detailed investigation of the etiology and appropriate treatment of anemia.

RESULTS

A total of 363 children aged between 24 and 48 months participated in this study, all of whom attended public day care centers in the part-time (morning/afternoon period) or full-time programs. There were no differences between children in the investigated regions in terms of sex or age, however, there was a polarization of adverse socioeconomic conditions for vulnerable regions (Table 1).

Table 1
Characterization and association of socioeconomic regions of day care centers with demographic and socioeconomic variables, Taubaté, 2014*.

The vulnerable population was associated with low maternal schooling, low family income, maternal work outside the household, beneficiaries of social programs, greater number of families with access to the FHS and the National Iron Supplementation Program (p<0.05).

Anemia was present in 19.3% of the children studied. Regarding the location of the day care centers they attended, there was a statistical difference in the medians of Hb concentration: day care centers with high socioeconomic vulnerability had more anemic children than those in non-vulnerable regions. An even lower concentration of Hb was observed in boys and children of mothers with less schooling (p<0.05), as shown in Table 2.

Table 2
Association of hemoglobin concentration (Hb) and prevalence of anemia with demographic and socioeconomic variables, Taubaté, 2014*.

In the multiple regression model, it was shown that only the day care center region variable remained in the model, since high socioeconomic vulnerability has greater explanatory power for iron deficiency anemia in this population than the other independent variables. Thus, attending a day care center in a socially and economically vulnerable region was the variable in which preschoolers had the lowest Hb concentrations (Table 3).

Table 3
Multivariate regression model among the determinants of hemoglobin concentration in preschoolers, Taubaté, 2014.

DISCUSSION

The prevalence of anemia found in the city of Taubaté is classified as a mild to moderate public health problem,11. World Health Organization [homepage on the Internet]. The global prevalence of anaemia in 2011. Geneva: WHO; 2015 [cited 2016 Dec 10]. Available from: Available from: http://www.who.int/nutrition/publications/micronutrients/global_prevalence_anaemia_2011/en/
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possibly reflecting access to health and education for the municipality’s population. In this way, this sensitive group responds better to the good conditions of basic public services that serve almost the entire population. This condition is justified by the high access of children to day care centers, regardless of the family’s socioeconomic region, by the greater number of years of maternal schooling and by the fact that low-income groups are the biggest beneficiaries of income transfer and basic health care programs, as characterized by the population.

Analyzes of socioeconomic vulnerability on the prevalence of anemia in preschoolers are current and relevant, since the factors that influence the prevalence of anemia are not only related to income, but rather to the complex set of variables that act in isolation or in clusters on the development of this condition, which makes it necessary to use other indicators in the investigation of vulnerable population groups.1010. Nakamura E, Egry EY, Campos CM, Nichiata LY, Chiesa AM, Takahashi RF. The potential of an instrument to identify social vulnerabilities and health needs: collective health knowledge and practices. Rev Latino-Am Enfermagem. 2009;17:253-8. http://dx.doi.org/10.1590/S0104-11692009000200018
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These indicators, in a simplified way, have already been used in some studies,1212. Vasconcelos PN, Cavalcanti DS, Leal LP, Osório MM, Batista-Filho M. Time trends in anemia and associated factors in two age groups (6-23 and 24-59 months) in Pernambuco State, Brazil, 1997-2006. Cad Saude Publica. 2014;30:1777-87. http://dx.doi.org/10.1590/0102-311X00117313
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,1313. Leal LP, Batista Filho M, Lira PI, Figueiroa JN, Osório MO. Temporal trends and anaemia-associated factors in 6- to 59-month-old children in Northeast Brazil. Public Health Nutr. 2012;15:1645-52. https://doi.org/10.1017/S1368980012000626
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as the unfavorable conditions in the economic and social levels of the family are part of the distal and proximal determinants of childhood anemia.1414. Leal LP, Osório MM. Associated factors of anemia in children under six years old: a systematic review of the population studies. Rev Bras Saúde Mater Infant. 2010;10:417-39. http://dx.doi.org/10.1590/S1519-38292010000400003
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The prevalence of anemia found according to age groups corroborate those observed for Brazil, with 21.7% for children aged 24 to 35 months and 19.6% for those aged 36 to 59 months.66. Brazil - Ministério da Saúde. Pesquisa Nacional de Demografia e Saúde da Criança e da Mulher - PNDS 2006: dimensões do processo reprodutivo e da saúde da criança. Brasília: Ministério da Saúde; 2009. This is explained by the inverse relationship between age and the prevalence of anemia: children between the ages of two and four present a different situation regarding the risk of iron deficiency when compared to infants, since they are no longer exposed to the great demands of iron resulting from the high speed of growth seen especially in the first two years of life. In addition, the dietary intake of children over two years of age is no longer based on breast milk, being similar to adult eating habits in composition and consistency, which reflects a consumption of greater amounts of source foods, as well as foods fortified with iron, which translates into the decrease in prevalence found in studies that analyzed the presence of anemia in childhood.66. Brazil - Ministério da Saúde. Pesquisa Nacional de Demografia e Saúde da Criança e da Mulher - PNDS 2006: dimensões do processo reprodutivo e da saúde da criança. Brasília: Ministério da Saúde; 2009.,1515. Novaes TG, Gomes AT, Silveira KC, Magalhães EI, Souza CL, Pereira Netto M, et al. Prevalence and factors associated with anemia in children enrolled in daycare centers: a hierarchical analysis. Rev Paul Pediatr. 2017;35:281-8. https://doi.org/10.1590/1984-0462/;2017;35;3;00008
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When comparing the percentage of childhood anemia in Brazil, there is a different situation from other developing countries, such as Vietnam, Benin and Mali, with prevalence rates of 45.1, 82 and 83%, respectively.1616. Nguyen PH, Nguyen KC, Le Mai B, Nguyen TV, Ha KH, Bern C, et al. Risk factors for anemia in Vietnam. Southeast Asian J Trop Med Public Health. 2006;37:1213-23.,1717. Ngnie-Teta I, Receveur O, Kuate-Defo B. Risk factors for moderate to severe anemia among children in Benin and Mali: insights from a multilevel analysis. Food Nutr Bull. 2007;28:76-89. https://doi.org/10.1177/156482650702800109
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The same occurs in different regions of Brazil: cities with different HDIs exhibit high prevalence of nutritional deficiencies.1818. Vieira RC, Ferreira HS. Prevalence of anemia in Brazilian children in different epidemiological scenarios. Rev Nutr. 2010;23:433-44. http://dx.doi.org/10.1590/S1415-52732010000300011
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This inconsistency in global and regional situations can be justified by the “pan-social” character of iron deficiency that affects rich and poor countries,11. World Health Organization [homepage on the Internet]. The global prevalence of anaemia in 2011. Geneva: WHO; 2015 [cited 2016 Dec 10]. Available from: Available from: http://www.who.int/nutrition/publications/micronutrients/global_prevalence_anaemia_2011/en/
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or families from different income strata within the same country or region.1414. Leal LP, Osório MM. Associated factors of anemia in children under six years old: a systematic review of the population studies. Rev Bras Saúde Mater Infant. 2010;10:417-39. http://dx.doi.org/10.1590/S1519-38292010000400003
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In accordance with our findings, in the state of Pernambuco, Northeastern Brazil, a decrease in the prevalence of anemia was reported for children older than 24 months of age within a decade, with the economic index being the only one that remained associated with anemia.1212. Vasconcelos PN, Cavalcanti DS, Leal LP, Osório MM, Batista-Filho M. Time trends in anemia and associated factors in two age groups (6-23 and 24-59 months) in Pernambuco State, Brazil, 1997-2006. Cad Saude Publica. 2014;30:1777-87. http://dx.doi.org/10.1590/0102-311X00117313
https://doi.org/http://dx.doi.org/10.159...

In this sense, despite these considerations, it is noteworthy that the level of Hb concentration is significantly lower in children attending day care centers in regions of high socioeconomic vulnerability. This is possibly due to the numerous and complex coexistence factors in the etiology of anemia. Even though Brazil has improved the situation of malnutrition, basic sanitation and child morbidity,1919. Victora CG, Aquino EM, Leal MC, Monteiro CA, Barros FC, Szwarcwald CL. Maternal and child health in Brazil: progress and challenges. Lancet. 2011;377:1863-76. https://doi.org/10.1016/S0140-6736(11)60138-4
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differences still persist, conditioned by the high inequality in the distribution of income in the strata of society.

In the city of Taubaté, although the Gini coefficient, used to measure inequality in income distribution, is better than that of the national context,2020. Silva DF, Vieira ET, Rosa LC, Xavier MI. Salário mínimo e segurança alimentar em Taubaté-SP. RBGDR. 2007;3:70-83. socioeconomic inequality is present in the assessed population. In this perspective, Barata et al.2121. Barata RB, Ribeiro MC, Cassanti AC,Grupo do Projeto Vulnerabilidade Social no Centro de São Paulo. Social vulnerability and health status: a household survey in the central area of a Brazilian metropolis. Cad Saude Publica. 2011;27 (Supl 2):s164-75. http://dx.doi.org/10.1590/S0102-311X2011001400005
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consider that, through the analysis of family income and education, it is possible to make a direct association with the health status of individuals, in addition to allowing the definition of a framework of social vulnerability.

Thus, the division of day care centers according to their location in regions distributed by socioeconomic vulnerability, as a synthesis variable, was explanatory for the different concentrations of Hb. This result is in line with the literature, given that populations most susceptible to anemia live on the periphery of urban centers, suffer from the lack of job opportunities, low wages and poor housing, education and health conditions.1414. Leal LP, Osório MM. Associated factors of anemia in children under six years old: a systematic review of the population studies. Rev Bras Saúde Mater Infant. 2010;10:417-39. http://dx.doi.org/10.1590/S1519-38292010000400003
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This finding, however, was not described by Bueno et al.2222. Bueno MB, Selem SS, Arêas JA, Fisberg RM. Prevalence and associated factors for anemia among children of public day-care centers in the city São Paulo. Rev Bras Epidemiol. 2006;9:462-70. http://dx.doi.org/10.1590/S1415-790X2006000400007
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when they assessed the prevalence of anemia among children in public day care centers in the various administrative divisions of the city of São Paulo, possibly because it is a population with homogeneous socioeconomic characteristics.

Consequently, research aimed at families that suffer socioeconomic inequality is important, as children in situations of social inequity have higher prevalence of anemia because they do not alleviate poor child health conditions among upper and middle social classes, as is the case in population-based studies that mitigate the prevalence rates of nutritional deficiencies of vulnerable populations with those of economically non-vulnerable populations.1818. Vieira RC, Ferreira HS. Prevalence of anemia in Brazilian children in different epidemiological scenarios. Rev Nutr. 2010;23:433-44. http://dx.doi.org/10.1590/S1415-52732010000300011
https://doi.org/http://dx.doi.org/10.159...

The disproportionality of populations of low socioeconomic status who suffer more from iron deficiency, especially in developing countries, points to flaws in strategies to control anemia worldwide.2323. Balarajan Y, Ramakrishnan U, Özaltin E, Shankar AH, Subramanian SV. Anaemia in low-income and middle-income countries. Lancet. 2011;378:2123-35. http://dx.doi.org/10.1590/S1415-790X2006000400007
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Watchful of this, the World Health Organization (WHO) recommended more specific measures, with a view to putting pressure on developing countries in the search for alternatives to control anemia,2424. World Health Organization. Guideline: use of multiple micronutrient powders for home fortification of foods consumed by infants and children 6-23 months of age. Geneva: WHO ; 2011. thus promoting a great debate on the development of new strategies against nutritional deficiencies globally.

In Brazil, even with the implementation of a strategy to control iron deficiency, considered the most effective - fortification of wheat and corn flours -, the prevalence of anemia remains especially high among the population with lower socioeconomic status, possibly due to problems in public policies and the absence of actions to control this nutritional deficiency in the more than 10 years following the implementation of this strategy. The unmet expectation in the control of iron deficiency may be a consequence of low consumption and low bioavailability of the iron used in fortified products2525. Santos Q, Nilson EA, Verly J E, Sichieri R. An evaluation of the effectiveness of the flour iron fortification programme in Brazil. Public Health Nutr. 2015;18:1670-74. https://doi.org/10.1017/S1368980014002055
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or even failures in the coverage and adherence of iron supplementation in health units and the absence of adequate guidance services.2626. Cembranel F, Corso AC, González-Chica DA. Coverage and adequacy of ferrous sulfate supplementation in the prevention of anemia among children treated at health centers of Florianopolis, Santa Catarina. Rev Paul Pediatr. 2013;31:315-23. https://doi.org/10.1590/S0103-05822013000300007
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Thus, taking into account the latest WHO guidance, which indicates the use of multiple micronutrients in powder form for homemade fortification as an alternative,2424. World Health Organization. Guideline: use of multiple micronutrient powders for home fortification of foods consumed by infants and children 6-23 months of age. Geneva: WHO ; 2011. a new intervention was formulated by the Brazilian government in partnership with national and international institutions, named NutriSUS, which aims to improve iron status and reduce anemia in children aged between 6 and 23 months.2727. Brazil - Ministério da Saúde. NutriSUS: guia de evidências: estratégia de fortificação da alimentação infantil com micronutrientes (vitaminas e minerais) em pó. Brasília (DF): Ministério da Saúde; 2015. Even knowing the effectiveness of this interventionist measure,2828. Cardoso MA, Augusto RA, Bortolini GA, Oliveira CS, Tietzman DC, Sequeira LA, et al. Effect of providing multiple micronutrients in powder through primary healthcare on anemia in young Brazilian children: a multicentre pragmatic controlled trial. PLoS One. 2016;11:e0151097. https://doi.org/10.1371/journal.pone.0151097
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the real effectiveness has not yet been evaluated, since the implementation process is recent. However it can be said in a simplistic way that this is another superficial action to solve the issue of low-income families, victims of childhood anemia, as interventions that do not deal with the proximal determinants of anemia are aimed at the same problems faced by existing interventionist strategies. After all, it is known that the main measure that definitively minimizes the risk of anemia is the diet with the best iron potential.

As was found in the results of this study, since the service is similar in all preschool units in the city of Taubaté, regardless of the location of the day care center, it can be assumed that the difference in family feeding practices is the main determinant of iron deficiency, since children are given the same school lunch. This point brings to the discussion a fundamental aspect hitherto presumed, diet as a determinant of health.

In this context, a more in-depth analysis on the topic involves the human right to adequate food, which protects both the health and the dignity of a population. According to General Comment No. 12 of the Committee on Economic, Social and Cultural Rights, the human right to adequate and healthy food for everyone and at all times is not restricted to the minimum number of calories required per day, but integrates a set of rights related to social, economic, cultural, climatic, ecological adequacy, among others.2929. United Nations [homepage on the Internet]. Committee on Economic, Social and Cultural Rights. General comment 12: the right to adequate food. Geneva: United Nations; 1999. [cited 2008 Nov 20]. Available from: Available from: https://documents-dds-ny.un.org/doc/UNDOC/GEN/G99/420/12/PDF/G9942012.pdf?OpenElement
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Brazil has made progress in this regard by creating the National System of Food and Nutritional Security to monitor and evaluate the nutritional situation of the population and act jointly in the formulation and implementation of policies and actions to fight hunger.3030. Rigon SA, Schmidt ST, Bógus CM. Nutritional challenges in the Brazilian Unified National Health System for building the interface between health and food and nutritional security. Cad Saude Publica. 2016;32:e00164514. http://dx.doi.org/10.1590/0102-311X00164514
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However, it is known that many structural challenges permeate the guarantee of the right to food and health, the main promoters of justice and social equity. In addition, one cannot ignore the fact that the consequences of anemia for the country affect not only children, but the entire population. Its high indirect cost in reducing the work capacity due to shortages in the employment of men and women,22. Haas JD, Brownlie T 4th. Iron deficiency and reduced work capacity: a critical review of the research to determine a causal relationship. J Nutr. 2001;131:676S-88S. https://doi.org/10.1093/jn/131.2.676S
https://doi.org/https://doi.org/10.1093/...
maternal mortality, prematurity, low weight of children at birth and, above all, the possible consequences on cognitive development that occur in childhood and translate into failure and dropping out of school over the course of life, imposing, in the future, a substantial burden on the country’s economy.33. Grantham-McGregor S, Ani C. A review of studies on the effect of iron deficiency on cognitive development in children. J Nutr. 2001;131:649S-66S. https://doi.org/10.1093/jn/131.2.649S
https://doi.org/https://doi.org/10.1093/...

In another scenario of discussion, when the prevalence of anemia related to the birth weight of these children is observed, it is clear that those with low weight at birth had a lower risk than those with higher weight at birth (>2500 g). Even if not statistically significant, it may indicate that the care provided to children with low weight at birth may have protected them from childhood anemia. It is known that such children should receive differentiated assistance in health services, as well as by family members, involving the monitoring of biological, social and affective aspects.

Anemia, being a pathology that does not indicate specific signs or symptoms, is not valued by the population or even by the health teams that monitor apparently healthy children. Therefore, it is recommended that health services work through food and nutrition education to raise the population’s awareness of the risks arising from iron deficiency and the deleterious consequences that lead to quality of life.

Although the cross-sectional study model may have limitations as it does not achieve a definite cause-and-effect relationship like longitudinal research, it allows reflection on the situational event and the status quo, being an adequate instrument for formulating hypotheses that can be investigated with new studies.

Thus, it was observed that a lower concentration of Hb in preschoolers is associated with the location of day care centers in a region of socioeconomic vulnerability, since children who attend such day care centers face adverse family conditions such as low income, working mothers with low schooling, although they receive social benefits and health monitoring by the FHS and the National Iron Supplementation Program.

The high HDI of the studied municipality does not seem to have the expected effectiveness in the fight against anemia, even with favorable life indicators, since the minimally unfavorable socioeconomic conditions of the family are still responsible for lower Hb concentrations in children. In view of the analysis of the most proximal factor of nutritional deficiency, which is diet, it can be assumed that when equal conditions are offered in the provision of school lunches in day care centers, the most appropriate public intervention to minimize the risk of childhood anemia in the population is the definitive improvement of family eating conditions, with increased income and social benefits, expansion of health strategies and services, as well as maternal work and schooling conditions.

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Publication Dates

  • Publication in this collection
    21 May 2020
  • Date of issue
    2020

History

  • Received
    03 Feb 2019
  • Accepted
    14 May 2019
  • Published
    21 May 2020
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