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Vitamin A deficiency among Brazilian school-aged children in a healthy child service

V I C Custodio1, J C Daneluzzi, R J Custodio

  • 1Department of Pediatrics, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil. cimadas@uol.com.br

European Journal of Clinical Nutrition
|November 29, 2007
PubMed

Insights

Vitamin A deficiency (VAD) is a public health concern, affecting 20.4% of Brazilian school-aged children. This subclinical deficiency occurred even without identified risk factors, highlighting a need for continued monitoring.

Area of Science:

  • Public Health
  • Nutrition Science
  • Pediatrics

Background:

  • Vitamin A deficiency (VAD) poses a significant global public health challenge, particularly in developing nations, contributing to childhood illness and mortality.
  • Severe VAD can lead to xerophthalmia and irreversible blindness.

Purpose of the Study:

  • To determine the prevalence of VAD in Brazilian school-aged children attending a primary health unit.
  • To investigate potential associations between VAD and identified risk factors in this population.

Main Methods:

  • A descriptive, prospective, transverse study involving 103 randomly selected school-aged children (5.5-11 years).
  • The relative dose-response (RDR) test was used to assess vitamin A status.
  • Ocular health, anemia, serum zinc, acute-phase proteins, and anthropometric data were analyzed.

Main Results:

  • No cases of xerophthalmia were observed.
  • The prevalence of hypovitaminosis A, as detected by the RDR test, was 20.4%.
  • No statistically significant associations were found between VAD and the evaluated risk factors (sex, weight, height, hemoglobin, C-reactive protein, alpha-1-acid-glycoprotein, serum zinc).

Conclusions:

  • The prevalence of VAD in this population warrants public health attention.
  • School-aged children are potentially at risk for subclinical VAD, irrespective of common associated risk factors.
Abstract

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