Rela????o entre os n??veis de vitamina A e os marcadores bioqu??micos do estado nutricional de ferro em crian??as e adolescentes / Relationship between vitamin A and biochemical markers of iron status in children and adolescents

Verificar a rela????o entre vitamina A e os marcadores bioqu??micos da situa????o nutricional do ferro. M??TODOS: Participaram deste estudo 178 indiv??duos com idade entre 7 e 17 anos, residentes na cidade de Jequi?? (BA). Os indiv??duos foram submetidos a exame de sangue para dosagem de retinol e de marcadores bioqu??micos do estado nutricional relativo ao ferro. Al??m disso, foram realizados exames antropom??tricos, parasitol??gico de fezes e coletadas informa????es de consumo diet??tico de ferro e das condi????es s??cio-ambiental e domiciliar da fam??lia. Utilizou-se a an??lise de regress??o linear m??ltipla como t??cnica estat??stica para avaliar a associa????o de interesse. RESULTADOS: Constatou-se associa????o positiva e estatisticamente significante entre os n??veis de retinol s??rico e a concentra????o de hemoglobina (p=0,007), ferro s??rico (p=0,010) e transferrina saturada (p=0,027). Esses efeitos se mantiveram ap??s ajuste dos modelos pelas vari??veis demogr??ficas, infec????es parasit??rias (Schistosoma mansoni, Trichiura trichuris, Ascaris lumbricoides e ancilostom??deos), consumo de ferro alimentar biodispon??vel e condi????es ambientais e domiciliares. CONCLUS??O: A vitamina A parece contribuir para elevar o ferro org??nico da popula????o, em especial, em ??reas onde a defici??ncia de vitamina A e a anemia coexistem.The objective of this study was to verify the relationship between vitamin A and the biochemical markers of iron status. METHODS: A total of 178 individuals aging from 7 to 17 years participated in this study, all living in Jequi??, BA. The individuals were submitted to blood tests to dose retinol and biochemical iron markers. Furthermore, anthropometric measurements and stool analyses were done and dietary information regarding iron intake, socio-environmental and home conditions of the family were collected. Multiple linear regression analysis was done to assess the association of interest. RESULTS: A positive and statistically significant association was found between the levels of serum retinol and hemoglobin (p=0.007), serum iron (p=0.010) and iron-saturated tranferrin (p=0.027). These findings remained unchanged after adjusting the models for demographic variables, parasitic infections (Schistosoma mansoni, Trichiura trichuris, Ascaris lumbricoides and ancylostomiasis), consumption of bioavailable dietary iron and environmental and home conditions. CONCLUSION: Vitamin A seems to contribute to the increase of organic iron of the population, especially in areas were deficiency of vitamin A and iron-deficiency anemia coexist