Prevalence of iron-deficiency anemia in Brazil: a systematic review

OBJECTIVE: To conduct a systematic review on the prevalence of anemia due to iron-deficiency in Brazil from January 1996 to January 2007. DATA SOURCES: A systematic review was conducted in electronic databases (Medline and Lilacs) in an eleven-year interval to verify the prevalence of iron deficiency anemia in children who were less than five years of age in Brazil. Reviews, case reports and studies related to anemia during pregnancy and anemia caused by others diseases were excluded. In order to describe the categorical variables according to the selected articles, the chi-square and Fisher exact tests were used. The significance level adopted was 5% (p<0.05). DATA SYNTHESIS: The median prevalence level of anemia was 53%, which is considered a high prevalence rate by the World Health Organization. Among the 53 analyzed studies, the age of the children was the variable strongly associated with anemia (p=0.012). CONCLUSIONS: A high prevalence of anemia, mostly in children less than two years of age, was observed in this review. However, most studies were carried out in day care centers or in Basic Health Care Units or were obtained by home interviews, suggesting that future research should focus populational studies.OBJETIVO: Revisar os estudos de prevalência de anemia no Brasil publicados entre janeiro de 1996 e janeiro de 2007. FONTES DE DADOS: Por meio de revisão sistemática nas bases de dados eletrônicas Medline e Lilacs, foram selecionados títulos científicos publicados no intervalo de onze anos referentes à prevalência de anemia no Brasil em crianças menores de cinco anos de idade. Foram excluídos artigos de revisão, relatos de caso e trabalhos que relacionaram anemia a outras doenças e ao período gestacional. Para a análise comparativa das variáveis categóricas de interesse nos artigos encontrados, realizou-se o teste do qui-quadrado e o teste exato de Fisher, levando-se em conta o nível de significância estatística de 5% (p