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Magnitude, time trends and factors associate with anemia in children in the state of Paraíba, Brazil

Abstracts

OBJECTIVE: To estimate the magnitude of the anemia, to analyze the time trends and investigate the factors associated with this disturbance in children in the state of Paraíba, Brazil. METHODS: A cross-sectional survey, of population-based, with 1108 children, aged 6 to 59 months, both sexes in the state of Paraíba. Hemoglobin (Hb) in venous blood was analyzed with an automatic counter. The social-economic and demographic characteristics of children were obtained by questionnaire. Proportions were compared by Pearson's chi-squared test, and the association between hemoglobin concentrations and potential risk factors was tested by regression model Poisson. The time trend of anemia was assessed by the increase/decreased in the prevalence of anemia, using as comparison the prevalence observed in the years 1982, 1992 and 2007. RESULTS: The prevalence of anemia (Hb < 11.0 g/dl) in the state of Paraíba was 36.5% (CI95% 33.7 to 39.3). It was observed that 1.3% (CI95% 0.7 to 1.8) were in severe form (Hb <7.0 g/dl), 11% (CI95% 9.4 to 13.5) in a moderate form and 87.6% (CI95% 79.1 to 91.2) in the mild form. There was an increase 88.5% in cases of anemia between the years 1982-1992 and stabilization in the prevalence between the years 1992-2007. The analysis adjusted Poisson model showed a greater susceptibility to anemia in children 6 to 24 months of age, those breastfed for six months or more, who co-inhabited with more than 04 people in the same household and lived in houses with less than 05 rooms. CONCLUSIONS: The results revealed that anemia remains an important public health problem in the state of Paraíba and despite having been shown an stabilization in the prevalence of anemia between 1992-2007, differently the prevalence observed between 1982-1992, this deficiency presents in high level, witch requires more effective measures of prevention and control.

Child; Anemia, epidemiology; Socioeconomic Factors; Risk Factors; Cross-Sectional Studies


OBJETIVO: Estimar a prevalência da anemia em crianças, sua tendência temporal e identificar fatores associados. MÉTODOS: Estudo de corte transversal, de base populacional, envolvendo 1.108 crianças, com idade entre seis e 59 meses, de ambos os sexos, do Estado da Paraíba, em 2007. A hemoglobina foi analisada em sangue venoso com contador automático. Foram considerados para anemia valores < 11,0 g/dL, forma leve 9-11g/dL, moderada 7-9 g/dL e grave < 7,0 g/dL. As condições socioeconômicas e demográficas das crianças foram obtidas por meio de questionário aos pais ou responsáveis. As proporções foram comparadas pelo teste do qui-quadrado de Pearson, e a associação entre as concentrações de hemoglobina e potenciais fatores de riscos foi testada pelo modelo de regressão de Poisson. A tendência temporal da anemia foi avaliada pelo incremento/redução na prevalência de anemia nos anos de 1982, 1992 e 2007. RESULTADOS: A prevalência de anemia foi de 36,5% (IC95% 33,7;39,3). Observa-se que 1,3% (IC95% 0,7;1,8) foi na forma grave, 11,1% (IC95% 9,4;13,5) na forma moderada e 87,6% (IC95% 79,1;91,2) na forma leve. Houve um incremento de 88,5% nos casos de anemia no período entre 1982 e1992 e uma estabilização na prevalência entre 1992 e 2007. A análise ajustada no modelo de Poisson mostrou maior suscetibilidade à anemia nas crianças de seis a 24 meses de idade, naquelas amamentadas por seis meses ou mais, que co-habitavam com mais de quatro pessoas no mesmo domicílio e moravam em casas com menos de cinco cômodos. CONCLUSÕES: A alta prevalência de anemia mostra que continua sendo um importante problema de saúde pública no Estado da Paraíba. Apesar da estabilização na prevalência entre 1992 e 2007, a anemia apresenta-se em elevado patamar, o que impõe medidas mais efetivas de prevenção e controle.

Criança; Anemia, epidemiologia; Fatores Socioeconômicos; Fatores de Risco; Estudos Transversais


OBJETIVO: Estimar la prevalencia de la anemia en niños, su tendencia temporal e identificar factores asociados. MÉTODOS: Estudio de corte transversal, de base poblacional, involucrando 1.108 niños, con edad entre 6 a 59 meses, de ambos sexos, del Estado de Paraíba, en 2007. La hemoglobina fue analizada en sangre venosa con contador automático. Se consideraron para anemia valores <11,0 g/dL, forma leve 9-11g/dL, moderada 7-9g/dL y grave <7,0g/dL. Las condiciones socioeconómicas y demográficas de los niños fueron obtenidos por medio de cuestionario a los padres o responsables. Las proporciones fueron comparadas por la prueba de Chi-cuadrado de Pearson, y la asociación entre las concentraciones de hemoglobina y potenciales factores de riesgo fue evaluada por el modelo de regresión de Poisson. La tendencia temporal de la anemia fue evaluada por el incremento/reducción en la prevalencia de anemia en los año de 1982, 1992 e 2007. RESULTADOS: La prevalencia de anemia fue de 36,5% (IC95% 33,7;39,3). Se observa que 1,3% (IC95% 0,7;1,8) fueron en la forma grave, 11,1% (IC95% 9,4;13,5) en la forma moderada y 87,6% (IC95% 79,1;91,2) en la forma leve. Hubo un incremento de 88,5% en los casos de anemia en el período entre 1982-1992 y una estabilización en la prevalencia entre 1992-2007. El análisis ajustado en el modelo de Poisson mostró mayor susceptibilidad a la anemia en los niños de seis a 24 meses de edad, en aquellos amamantados por seis meses o más, que cohabitaban con más de cuatro personas en el mismo domicilio y vivían en casas con menos de cinco cuartos. CONCLUSIONES: La alta prevalencia de anemia muestra que continúa siendo un problema importante de salud pública en el Estado de Paraíba. A pesar de la estabilización en la prevalencia entre 1992-2007, la anemia se presenta en nivel elevado, lo que impone medidas más efectivas de prevención y control.

Niño; Anemia, epidemiologia; Factores Socioeconómicos; Factores de Riesgo; Estudios Transversales


ORIGINAL ARTICLES

Magnitude, time trends and factors associate with anemia in children in the state of Paraíba, Brazil

Sheila Sherezaide Rocha GondimI; Alcides da Silva DinizI; Rafaela Alves de SoutoII; Roberta Gouveia da Silva BezerraII; Emídio Cavalcanti de AlbuquerqueIII; Adriana de Azevedo PaivaIV

IPrograma de Pós-Graduação em Nutrição. Universidade Federal de Pernambuco. Recife, PE, Brasil

IINúcleo de Estudos e Pesquisas Epidemiológicas. Universidade Estadual da Paraíba. Campina Grande, PB, Brasil

IIIInstituto de Medicina Integral Professor Fernando Figueira. Recife, PE, Brasil

IVPrograma de Pós-Graduação em Alimentos e Nutrição. Universidade Federal do Piauí. Teresina, PI, Brasil

Correspondence Correspondence: Sheila Sherezaide Rocha Gondim R. Auta Leite, 501 - Bela Vista 58428-745 Campina Grande, PB, Brasil E-mail: sheilasrg@yahoo.com.br

ABSTRACT

OBJECTIVE: To estimate the magnitude of the anemia, to analyze the time trends and investigate the factors associated with this disturbance in children in the state of Paraíba, Brazil.

METHODS: A cross-sectional survey, of population-based, with 1108 children, aged 6 to 59 months, both sexes in the state of Paraíba. Hemoglobin (Hb) in venous blood was analyzed with an automatic counter. The social-economic and demographic characteristics of children were obtained by questionnaire. Proportions were compared by Pearson's chi-squared test, and the association between hemoglobin concentrations and potential risk factors was tested by regression model Poisson. The time trend of anemia was assessed by the increase/decreased in the prevalence of anemia, using as comparison the prevalence observed in the years 1982, 1992 and 2007.

RESULTS: The prevalence of anemia (Hb < 11.0 g/dl) in the state of Paraíba was 36.5% (95%CI 33.7 to 39.3). It was observed that 1.3% (95%CI 0.7 to 1.8) were in severe form (Hb < 7.0 g/dl), 11% (95%CI 9.4 to 13.5) in a moderate form and 87.6% (95%CI 79.1 to 91.2) in the mild form. There was an increase 88.5% in cases of anemia between the years 1982-1992 and stabilization in the prevalence between the years 1992-2007. The analysis adjusted Poisson model showed a greater susceptibility to anemia in children 6 to 24 months of age, those breastfed for six months or more, who co-inhabited with more than four people in the same household and lived in houses with less than five rooms.

CONCLUSIONS: The results revealed that anemia remains an important public health problem in the state of Paraíba and despite having been shown an stabilization in the prevalence of anemia between 1992-2007, differently the prevalence observed between 1982-1992, this deficiency presents in high level, witch requires more effective measures of prevention and control.

Descriptors: Child. Anemia, epidemiology. Socioeconomic Factors. Risk Factors. Cross-Sectional Studies.

INTRODUCTION

Micronutrient deficiencies affect approximately one third of the world's population, damaging the health of individuals and the development of nations. The most common and widely distributed nutritional deficiency in the world is iron deficiency, the main cause of anemia in childhood. Despite the high prevalence and although its etiology is well known, it is a problem that persists even in developed countries.14

Iron deficiency is caused by an imbalance between the amount of iron that is biologically available and its organic need.20 It can be considered as the final result of a long period of negative iron balance. In the initial phase of iron deficiency (ID), the reserves in the form of ferritin and hemosiderin are adequate to maintain the iron serum levels at normal values, and only a reduction in the mineral in the organic deposits occurs. In the second phase, a reduction occurs in the plasma iron concentration, together with an increase in the total iron fixation capacity and the consequent decrease in the transferrin saturation percentage, as well as an increase in the concentration of free erythrocyte protoporphyrin, without significant modifications in the hemoglobin levels. In the third and last stage, iron deficiency anemia is produced, which is characterized by a sharp decrease in the concentration of hemoglobin, hematocrit and plasma iron.7

This nutritional disorder can cause important harmful effects in the individual. Even in the form of moderate iron deficiency, it has been associated with reduction in the productive capacity, cognitive development disorders and psychomotor development.5 ID has been generally associated with risk of low birth weight19 and reduction in the immunologic capacity, leading to greater susceptibility and to the occurrence of infections and high morbidity and mortality.ª a United Nations Children's Fund. Preventing iron deficiency in women and children technical consensus on key issues. New York: International Nutrition Foundation; 1999 [cited 2007 Aug 25]. Available from: http://www.inffoundation.org/pdf/prevent_iron_def.pdf In a more comprehensive way, there are the economic consequences, which are directly related to the costs of the treatment of prevailing cases: approximately 5% of the gross domestic product of developing countries is wasted on heath expenses deriving from ID anemia.21

It is estimated that more than two billion people in the world are affected by ID. Infants, preschoolers, pregnant women and non-pregnant women of childbearing age are the main risk groups.b b Pan American Health Organization. Gender, health and development in the America 2003. Washington (DC); 2003 [cited 2007 Jul 25]. Available from: http://www.paho.org/english/ad/ge/GenderBrochure.pdf Studies have shown a correlation between iron nutritional status and a series of determinants, such as: age,2,12,19,24 gender,6 maternal age, housing conditions and birth weight,20 number of co-inhabitants in the household,14 mother's level of schooling and per capita income,13 father's level of schooling,18 breastfeeding,15 among others.

In spite of all knowledge about the etiology and treatment of iron deficiency anemia, its high prevalence and spatial distribution in Brazil are well known. In the last ten years, the magnitude of the deficiency in infants ranged between 51.9% and 65.4%,2,6,9,18,20 and in preschoolers, it varied between 31.6% and 62.5%.1,12,19,24 Secular trends in anemia data in the State of São Paulo between 1984 and 1996 show a significant increase in the prevalence of the disease (from 35.6% to 46,5%).13

The Northeast region of Brazil, which is potentially vulnerable to nutritional deficiencies, presents high prevalence of anemia.2,12,20,24 In the State of Paraíba two important population-based epidemiological studies were carried out with preschoolers. The first one was conducted between 1981 and 1982 by Dricot D'Ans et alc c Driot D'ans C, Driot JME, Santos LMP, Asiutti LS. Estudo epidemiológio preliminar da desnutrição no Estado da Paraíba [relatório ténio]. João Pessoa; 1985. Apud: Arruda BKG. editor. A polítia alimentar e nutriional brasileira. In: Anais do 7° Congresso Latinoameriano de Nutriión; 1984; Brasília (DF). Jabotiabal: Fundaçäo de Estudos e Pesquisas em Agronomia Mediina Veterinária e Zootenia; 1984. p.7-56. and revealed a prevalence of 19.3% of anemia; the second, carried out in 1992 by Oliveira et al,17 revealed a prevalence of 36.4%.

Knowing the evolution of anemia after the implementation of intervention actions - especially the iron supplementation program and the program of wheat flour and corn flour fortification with iron and folic acid - is fundamental to control this nutritional disorder in childhood in the primary care services. Understanding the risk factors of each population enables to take efficient measures to prevent and control anemia.

This paper aimed to estimate the prevalence of anemia in children, its temporal trend, and to identify associated factors.

METHODS

A cross-sectional, cohort, population-based household survey was carried out between January and April 2007, with children aged six to fifty-nine months, of both sexes, living in the urban area of the State of Paraíba (Northeastern Brazil). The eligible subjects were children with these characteristics who did not present diarrhea, neurological problems or infectious diseases at the moment of the screening.

The sample was calculated by estimating a prevalence (p) of anemia of 36%.20 The basis for sample definition was the equation described in the formula N = [E2. p (1-p). c] /A2, in which E is the confidence limit (E = 1.96) for a margin of error of 5%; c is the cluster sample correction coefficient (c = 2.1); and A, the accepted precision for the estimated prevalence (A = 4.5%). The minimum sample size that was obtained (N) was of 919 children. Sample size was corrected by a proportional factor of 1.25 (100/100-80) to correct possible losses and allow for a better disaggregation of the independent variables, resulting in a final sample of 1,149 children.

The children were selected by multistage sampling. The population data of the State's municipalities were estimated for the year of 2006 according to the data of Instituto Brasileiro de Geografia e Estatística (IBGE - Brazilian Institute of Geography and Statistics),d d Instituto Brasileiro de Geografia e Estatística. Censo Demográfico 2000 [cited 2006 Sep 20]. Available from: http://www.sidra.ibge.gov.br/cd/defaultcd2000.asp?o=11&i=P and the number of children aged six to 59 months that lived in the urban zone was surveyed (15% of the population), with the respective accumulated populations.

After the calculation of the sample interval, the randomization of the municipalities was performed. The municipalities of João Pessoa and Campina Grande, located respectively in the mid-regions of Zona da Mata and Agreste, were intentionally selected because they are the municipalities that have the largest populations of the State. The municipalities of Patos, Belém do Brejo do Cruz, Boa Ventura, Conceição, Malta, Pedra Branca and São José de Espinharas, located in the mid-region of Sertão, were selected in a random, systematic way.

Then, the census tracts were drawn, followed by the number of households per tract, with maximum limit of 40 units, and finally, the sample unit. It was decided to assess all children residing in the household that met the eligibility criteria.

In the household the interviewer explained about the research and asked for the guardian's authorization for the child to participate in the research through the signature of a consent document. After the participation was authorized, the collection of the child's blood was scheduled at the Primary Family Health Units. After this, a socioeconomic and demographic questionnaire was administered.

The sample of 4 ml of blood was collected by means of the peripheral venipuncture technique. Of this amount, 2 ml were deposited in tubes without anticoagulant (serum obtention) to determine C-reactive protein (CRP) and 2 ml were deposited in tubes with the anticoagulant K3EDTA to analyze the hemoglobin concentrations.

The blood and serum samples that were obtained were adequately packaged and transported to the analysis laboratories, maintaining an unbroken cold chain.

The analyzes were performed at the Clinical Analyses Laboratory of Hospital Universitário Lauro Wanderley, Universidade Federal da Paraíba, in the city of João Pessoa. The hemoglobin (Hb) concentrations were determined by an automatic counter (Sysmex SF - 3000, Roche Diagnóstica). The children who presented Hb levels below 11.0 g/dL were considered anemic, taking into account the study's age group, according to the World Health Organization (WHO).e e World Halth Organization. Iron dficincy anmia assssmnt, prvntion, and control: a guid for programm managrs. Gnva; 2001. To define the degrees of anemia, the following categories were considered: mild anemia (Hb ≥ 9.0 to < 11.0 g/dL); moderate anemia (Hb ≥ 7.0 to < 9.0 g/dL); and severe anemia (Hb < 7.0 g/dL).

CRP concentrations were analyzed through the latex agglutination technique (SYMSMEX SF-3000, Roche Diagnóstica). CRP concentrations ≥ 6 mg/L were considered significant subclinical infection.22

A semi-structured questionnaire was used, with variables related to the mother (level of schooling, age), to the child (gender, age, breastfeeding duration, per capita income), and to the household (type of house, number of co-inhabitants, number of rooms, garbage collection, type of sewage, water availability).

The database was constructed through the program EpiInfo version 6.04 (WHO/CDC, Atlanta, GE, EUA), in double entry; then, the validate module was used to check for possible inconsistencies. The statistical analyzes were performed in the statistical programs SPSS version for Windows 13.0 and Stata version 9.0.

The variables presented normal distribution according to the Kolmogorov-Smirnov test. In the description of the proportions, the binomial distribution was approximated to the normal distribution by the 95% confidence interval. The proportions were compared by Pearson's chi-square test, and the strength of the association among proportions, by the prevalence ratio with the respective confidence interval.

The association between hemoglobin concentrations and potential risk factors was tested by Poisson's regression model.

The temporal trend of anemia was evaluated by the increase/decrease in the prevalence of anemia, and the following formula was employed: [prevalence A x Prevalence B / Prevalence A x 100]. The prevalences observed in the years of 1982,c c Driot D'ans C, Driot JME, Santos LMP, Asiutti LS. Estudo epidemiológio preliminar da desnutrição no Estado da Paraíba [relatório ténio]. João Pessoa; 1985. Apud: Arruda BKG. editor. A polítia alimentar e nutriional brasileira. In: Anais do 7° Congresso Latinoameriano de Nutriión; 1984; Brasília (DF). Jabotiabal: Fundaçäo de Estudos e Pesquisas em Agronomia Mediina Veterinária e Zootenia; 1984. p.7-56. 199217 and 2007 were used for the comparison.

The investigation project was approved by the Ethics Committee of Universidade Estadual da Paraíba (protocol nº 11280133000-05/2006). The diagnosed cases of anemia were referred to the Primary Care Units for specific treatment.

RESULTS

Of the total of 1,149 children that should participate in the study, 1,108 were evaluated, due to a 3.6% sample loss that was caused by problems related to the collection, processing and analysis of the biological material. The median of the children's age was 34.5 months (P25 = 19.0 and P75 = 46.0); 90.2% were children of mothers who had four or more years of schooling; 47.1% were children of mothers aged between 20 and 28 years; 80.2% of the children came from families with per capita income below 0.5 minimum salary; 86.3% lived in brick houses and 66.2% lived in houses with five or more rooms. The mean hemoglobin concentration was 11.2 g/dL (SD 1.2), with minimum concentration of 6.1 g/dL and maximum concentration of 15.6 g/dL.

The prevalence of anemia (Hb < 11g/dL) was 36.5 % (95%CI 33.7;39.3); 87.6% (95%CI 79.1;91.2) was of the mild form, 11.1% (95%CI 9.4;13.5) moderate and 1.3% (95%CI 0.7;1.8) severe.

There was a sharp increase in the number of cases of anemia (88.5%) in the period between 1982 and 1992, and stabilization in the period from 1992 to 2007, but in a high level (Figure).


In the univariate analysis, the following children presented greater vulnerability to anemia: children aged six to 24 months, children who were breastfed for six months or more, children of mothers younger than 20 years and belonging to families with per capita income below 0.5 minimum salary. Concerning housing conditions, the following children were more susceptible to anemia: those who lived in unfinished brick houses, in houses which had more than eight co-inhabitants, less than five rooms and no sewage system (Table 1).

The variables that represented potential confounding factors with association at the level of p < 0.20 in relation to anemia and that participated in Poisson's regression model were: child's age, breastfeeding duration, mother's age, per capita income, mother's level of schooling, type of construction of the house, number of co-inhabitants in the household, number of rooms of the house, public garbage collection, sewage system and public water supply. After the analysis of the adjusted model, the following variables remained associated with anemia: child's age, breastfeeding period, number of co-inhabitants in the house and number of rooms in the house (Table 2).

DISCUSSION

The results found in the present study indicate that iron deficiency anemia is a nutritional deficiency of great magnitude which continues to represent a public health problem of the moderate type (10% to 40%) in the State of Paraíba. The prevalence of anemia observed in the State of Paraíba (36.5%) was similar to the prevalences described in studies conducted in States of the Northeast region of Brazil.10,16

Analyzing the temporal trend of anemia in the studied ecological context, the stabilization in the prevalence of anemia in the period from 1992 to 2007 shows a trend profile that is significantly different from that of the period between 1982 and 1992, when there was a sharp increase in the problem, which has also been reported by Oliveira et al.17 This trend was somewhat unexpected, as its prevalence was expected to decrease, in consonance with what has been observed in temporal trend studies of other nutritional deficiencies, like protein-energy malnutrition. A possible explanation for this unexpected behavior would be the fact that, although sufficiently adequate in quantitative and energetic terms, these children's nutrition is deficient in iron, mainly that of high bioavailability, to meet their physiological needs. This high prevalence, although the mild form of anemia prevails, suggests that the measures to combat iron deficiency and anemia in children, like food fortification, oral iron supplementation and promotion of nutritional education, recommended by the WHO,e e World Halth Organization. Iron dficincy anmia assssmnt, prvntion, and control: a guid for programm managrs. Gnva; 2001. need to be implemented, monitored, and evaluated, so that the real impact of this interventions on the combat of nutritional anemia can be known.

The genesis of anemia seems to be associated with conjunctural and structural elements. Although iron deficiency is characteristically an organic problem, its occurrence is not reduced to this dimension, that is, to the processes generated by deficiencies in the consumption and absorption of foods and/or spoliation of this mineral. In order to know the totality of the causes of this disorder, it is necessary to consider the reality outside the human organism, like specific social processes which also determine iron deficiency.

The greater susceptibility to anemia in children younger than 24 months strengthens the hypothesis that the disease is significantly more prevalent among younger children, which has been ratified by other studies.3,9,10,19,24 This greater vulnerability might be attributed, mainly, to the accelerated growth and consequent increase in the iron needs in the first years of life.9 After the sixth month of age, with the end of the iron reserves that were acquired in the uterus, nutrition becomes fundamental to supply the mineral. Therefore, children younger than two years constitute a group of higher risk for anemia, as they present factors such as: early abandonment of exclusive breastfeeding, inadequate transition diet, as well as greater exposure to the contagion of infectious and parasitic diseases, due to greater contact with the external environment.

The greater vulnerability to anemia in the children who were breastfed during a larger period might be explained by the short duration of exclusive breastfeeding and the complementation with an iron-deficient nutrition. This process occurs simultaneously with the organism's greater requirement of an increased consumption of this mineral for an adequate erythropoiesis, due to the accelerated growth. Low iron reserves at birth can also represent an important factor in the triggering of anemia, since iron storage during intrauterine life and exclusive breastfeeding meet the needs of the infant in the first six months of life.15 In this sense, it should be emphasized that the duration of exclusive breastfeeding in Paraíba has been of only 22.4% of children younger than four months of age and 16.6% of children younger than six months,23 a prevalence that is well below what is recommended by the WHO.f f World Health Organization. World Health Assembly Resolution 47.5. Geneva; 1994. Kitoko et al,8 in a study carried out in the municipality of João Pessoa, found a prevalence of exclusive breastfeeding of 23.9% in children younger than four months, and revealed that only 24.8% of children aged six to nine months received what the WHOg g World Health Organization. Indicators for assessing breastfeeding practices. Geneva; 1991. considers to be timely complementary feeding. Furthermore, of this total, 40.5% did not include in the diet beans and meat, two important sources of iron.

Studies have verified the beneficial effect of exclusive breastfeeding in the first six months of life, as it increases the hemoglobin levels.11,15,16 In addition, the association of breastfeeding with the use of cow's milk has caused a decline in children's hemoglobin levels due to occurrences of intestinal microhemorrhages.11,15,16 As a preventive measure, combined with other interventions, it is necessary to implement actions to promote exclusive breastfeeding up to the sixth month of life and nutritional guidance about adequate complementation to breast milk up to two years, aiming to reduce the consumption of cow's milk and to stimulate the ingestion of foods with high density of heme iron.16

The greater risk of anemia in children with unfavorable housing conditions (number of co-inhabitants and number of rooms in the house) might be explained by the reduction in these families' economic accessibility, which leads to a per capita reduction in foods and to the consequent reduction in iron intake.10 The fact that anemia is more prevalent in households with lower number of rooms might be associated with factors that contribute to a greater dissemination of infectious diseases and intestinal parasitosis.13 This is a consequence of confinement and overpopulation, which, in turn, contribute to the increase in insalubrity. It is known that this process of iron spoliation occurs due to the microhemorrhages that are caused by the parasitosis, and by the reduction in iron absorption and the decrease in hemoglobin production as a result of infections.9

The non-association of anemia in the adjusted model with other variables that translate the socioeconomic status might be explained by the fact that it was represented in the adjusted model by other proxy variables, like housing condition. However, the distribution of anemia in the majority of the studied geographical spaces shows that iron deficiency exceeds the socioeconomic limits, since it occurs in countries that are considered developed. Many studies3,13 have shown that, the larger the child's family income, the more he/she is protected from anemia, due to the influence in the very quality of nutrition. To these authors, although individuals from any stratum are not immune to anemia, families of lower socioeconomic level are subject to a higher risk of developing the disease, and its prevalence tends to be lower in the strata of better socioeconomic level. The relevance of income level in the determination of anemia seems to derive from its effect on the quantity and quality of food, on the consumption of foods that are sources of heme iron, on the access to healthcare services and on the quality of housing and sanitation.4

Although the variable maternal age lost its strength of association in the regression analysis, children whose mothers were younger than 20 years were more susceptible to anemia. Similar findings from other studies10,13,20 lead us to suppose that these mothers' lack of maturity and knowledge influence the inadequate choice of complementary foods. Furthermore, adolescent mothers have higher probability of having preterm children, with low birth weight and, consequently, lower hemoglobin reserves.6

The results that were found in this study reiterate that anemia in the State of Paraíba continues to be an important public health problem and that little advance has been obtained regarding the reduction in this nutritional disorder, probably due to the fact that this deficiency is the final result of a series of biological, social, economic and cultural factors in which the child is included. As a measure to prevent and control this nutritional deficiency, it is necessary that the public health polices implement effective and urgent actions, mainly in the risk population; otherwise, irreversible damages may affect the population.

REFERENCES

Received: 8/12/2011

Approved: 3/15/2012

Research financed by Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq).

Process nº 402157/2005-2.Paper based on the doctoral dissertation authored by Gondim SSR, submitted to the Postgraduate Program in Nutrition of Universidade Federal de Pernambuco in 2011.

The authors declare there are no conflicts of interest.

  • 1. Almeida CAN, Ricco RG, Del Ciampo LA, Souza AM, Pinho AP, Oliveira JED. Fatores associados à anemia por deficiência de ferro em crianças pré-escolares brasileiras. J Pediatr (Rio J) 2004;80(3):229-34. DOI:10.2223/1188
  • 2. Assis AMO, Gaudenzi EM, Gomes G, Ribeiro RC, Szarfarc SC, Souza SB. Níveis de hemoglobina, aleitamento materno e regime alimentar no primeiro ano de vida. Rev Saude Publica 2004;38(4):543-51. DOI:10.1590/S0034-89102004000400010
  • 3. Assunção MCF, Santos IS, Barros AJD, Gigante DP, Victora CG. Anemia em menores de seis anos: estudo de base populacional em Pelotas, RS. Rev Saude Publica 2007;41(3): 328-35. DOI:10.1590/S0034-89102007000300002
  • 4. Borges CQ, Silva RCR, Assis AMO, Pinto EJ, Fiaccone RL, Pinheiro SMC. Fatores associados à anemia em crianças e adolescentes de escolas públicas de Salvador, Bahia, Brasil. Cad Saude Publica 2009;25(4):877-88. DOI:10.1590/S0102-311X2009000400019
  • 5. Brunken GS, Guimarães LV, Fisberg M. Anemia em crianças menores de 3 anos que frequentam creches públicas em período integral. J Pediatr (Rio J) 2002;78(1):50-6. DOI:10.1590/S0021-75572002000100011
  • 6. Compri PC, Cury MCFS, Novo NF, Juliano Y, Sigulem DM. Variáveis maternas e infantis associadas à ocorrência de anemia em crianças nos serviços de atenção básica em São Paulo. Rev Paul Pediatr 2007;25(4):349-54. DOI:10.1590/S0103-05822007000400009
  • 7. Gibson RS. Principles of nutritional assessment. New York: Oxford University Press; 1990.
  • 8. Kitoko PM, Rea MF, Venancio SI, Vasconcelos ACCP, Santos EKA, Monteiro CA. Situação do aleitamento materno em duas capitais brasileiras: uma análise comparada. Cad Saude Publica 2000;16(4):1111-9. DOI:10.1590/S0102-311X2000000400029
  • 9. Konstantyner T, Taddei JAAC, Palma D. Fatores de risco de anemia em lactentes matriculados em creches públicas ou filantrópicas de São Paulo. Rev Nutr. 2007;20(4):349-59. DOI:10.1590/S1415-52732007000400002
  • 10. Leal LP, Batista Filho M, Lira PIC, Figueiroa JN, Osório MM. Prevalência da anemia e fatores associados em crianças de seis a 59 meses de Pernambuco. Rev Saude Publica 2011;45(3):457-66. DOI:10.1590/S0034-89102011000300003
  • 11. Levy-Costa RB, Monteiro CA. Consumo de leite de vaca e anemia na infância no município de São Paulo. Rev Saude Publica 2004;38(6):797-803. DOI:10.1590/S0034-89102004000600007
  • 12. Miranda AS, Franceschini SCC, Priore SE, Euclides MP, Araújo RMA, Ribeiro SMR, et al. Anemia ferropriva e estado nutricional de crianças com idade de 12 a 60 meses do município de Viçosa, MG. Rev Nutr. 2003;16(2):163-9. DOI:10.1590/S1415-52732003000200003
  • 13. Monteiro CA, Szarfarc SC, Mondini L. Tendência secular da anemia na infância na cidade de São Paulo (1984-1996). Rev Saude Publica 2000;34(6 Supl):62-72. DOI:10.1590/S0034-89102000000700009
  • 14. Neuman NA, Tanaka OY, Szarfarc SC, Guimarães PRV, Victora CG. Prevalência e fatores de risco para anemia no sul do Brasil. Rev Saude Publica 2000;34(1):57-63. DOI:10.1590/S0034-89102000000100011
  • 15. Oliveira AS, Silva RCR, Fiaccone RL, Pinto EJ, Assis AMO. Efeito da duração da amamentação exclusiva e mista sobre os níveis de hemoglobina nos primeiros seis meses de vida: um estudo de seguimento. Cad Saude Publica 2010;26(2):409-17. DOI:10.1590/S0102-311X2010000200020
  • 16. Oliveira MAA, Osório MM, Raposo MCF. Fatores socioeconômicos e dietéticos de risco para a anemia em crianças de 6 a 59 meses de idade. J Pediatr (Rio J) 2007;83(1):39-46. DOI:10.2223/JPED.1579
  • 17. Oliveira RS, Diniz AS, Benigna MJC, Miranda-Silva SM, Lola MM, Gonçalves MC, et al. Magnitude, distribuição espacial e tendência da anemia em pré-escolares da Paraíba. Rev Saude Publica 2002;36(1):26-32. DOI:10.1590/S0034-89102002000100005
  • 18. Silva DG, Franceschini SCC, Priore SE, Ribeiro SMR, Szarfarc SC, Souza SB, et al. Anemia ferropriva em crianças de 6 a 12 meses atendidas na rede pública de saúde do município de Viçosa, Minas Gerais. Rev Nutr. 2002;15(3):301-8. DOI:10.1590/S1415-52732002000300006
  • 19. Souto TE, Oliveira MN, Casoy F, Machado EHS, Juliano Y, Gouvêa LC, et al. Anemia e renda per capita familiar de crianças frequentadoras da creche do Centro Educacional Unificado Cidade Dutra, no Município de São Paulo. Rev Paul Pediatr. 2007;25(2):161- 6. DOI:10.1590/S0103-05822007000200011
  • 20. Spinelli MGN, Marchioni DML, Souza JMP, Souza SB, Szarfarc SC. Fatores de risco para anemia em crianças de 6 a 12 meses no Brasil. Rev Panam Salud Publica 2005;17(2):84-91. DOI:10.1590/S1020-49892005000200004
  • 21. Szarfarc SC. Políticas públicas para o controle da anemia ferropriva. Rev Bras Hematol Hemoter. 2010;32(Supl 2)2-8. DOI:10.1590/S1516-84842010005000065
  • 22. Thurnham DI, McCabe GP, Northrop-Clewes CA, Nestel P. Effects of subclinical infection on plasma retinol concentrations and assessment of prevalence of vitamin A deficiency: meta-analysis. Lancet. 2003;362(9401):2052-8. DOI:10.1016/S0140-6736(03)15099-4
  • 23. Viana RPT, Rea MF, Venancio SI, Escuder MM. A prática de amamentar entre mulheres que exercem trabalho remunerado na Paraíba, Brasil: um estudo transversal. Cad Saude Publica 2007;23(10):2403-9. DOI:10.1590/S0102-311X2007001000015
  • 24. Vieira ACF, Diniz AS, Cabral PC, Oliveira RS, Lóla MMF, Silva SMM, et al. Avaliação do estado nutricional de ferro e anemia em crianças de 5 anos de creches públicas. J Pediatr (Rio J) 2007;83(4):370-6. DOI:10.1590/S0021-75572007000500014
  • Correspondence:
    Sheila Sherezaide Rocha Gondim
    R. Auta Leite, 501 - Bela Vista
    58428-745 Campina Grande, PB, Brasil
    E-mail:
  • a
    United Nations Children's Fund. Preventing iron deficiency in women and children technical consensus on key issues. New York: International Nutrition Foundation; 1999 [cited 2007 Aug 25]. Available from:
  • b
    Pan American Health Organization. Gender, health and development in the America 2003. Washington (DC); 2003 [cited 2007 Jul 25]. Available from:
  • c
    Driot D'ans C, Driot JME, Santos LMP, Asiutti LS. Estudo epidemiológio preliminar da desnutrição no Estado da Paraíba [relatório ténio]. João Pessoa; 1985. Apud: Arruda BKG. editor. A polítia alimentar e nutriional brasileira. In: Anais do 7° Congresso Latinoameriano de Nutriión; 1984; Brasília (DF). Jabotiabal: Fundaçäo de Estudos e Pesquisas em Agronomia Mediina Veterinária e Zootenia; 1984. p.7-56.
  • d
    Instituto Brasileiro de Geografia e Estatística. Censo Demográfico 2000 [cited 2006 Sep 20]. Available from:
  • e
    World Halth Organization. Iron dficincy anmia assssmnt, prvntion, and control: a guid for programm managrs. Gnva; 2001.
  • f
    World Health Organization. World Health Assembly Resolution 47.5. Geneva; 1994.
  • g
    World Health Organization. Indicators for assessing breastfeeding practices. Geneva; 1991.
  • Publication Dates

    • Publication in this collection
      24 July 2012
    • Date of issue
      Aug 2012

    History

    • Received
      12 Aug 2011
    • Accepted
      15 Mar 2012
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