Iodine deficiency in women of childbearing age in Brazil: systematic review and meta-analysis

  • Rosa Camila Lucchetta Department of Drugs and Medicines, School of Pharmaceutical Sciences, São Paulo State University (UNESP), São Paulo, Brazil
  • Ana Luísa Rodriguez Gini Department of Drugs and Medicines, School of Pharmaceutical Sciences, São Paulo State University (UNESP), São Paulo, Brazil
  • Sophia de Andrade Cavicchioli University of Araraquara (Uniara), Araraquara, São Paulo, Brazil
  • Marcela Forgerini Department of Drugs and Medicines, School of Pharmaceutical Sciences, São Paulo State University (UNESP), São Paulo, Brazil
  • Fabiana Rossi Varallo Department of Pharmaceutical Sciences, Faculty of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo (USP), São Paulo, Brazil
  • Mariane Nunes de Nadai Bauru School of Dentistry, University of São Paulo (USP), Bauru, Brazil
  • Fernando Fernandez-Llimós Laboratory of Pharmacology, Department of Drug Sciences, Faculty of Pharmacy, University of Porto, Porto, Portugal
  • Patricia de Carvalho Mastroianni Department of Drugs and Medicines, School of Pharmaceutical Sciences, São Paulo State University (UNESP), São Paulo, Brazil
Keywords: Iodine deficiency, Prevalence study, Nutritional Epidemiology, Maternal Nutrition, Women's Health


Background: Despite current policies of salt iodination, iodine deficiency is still a global public health problem, especially in women. So far, conflicting evidence has been suggested for the prevalence of iodine deficiency in Brazil. Objective: To estimate the prevalence of iodine deficiency and associated factors in women of childbearing age in Brazil. Methods: A systematic review was conducted using databases (PubMed, LILACS, WHO, Scopus, and Capes’ dissertation and thesis), from inception to May 2020. Meta-analyses of proportions were performed using the variance inverse for the fixed model. Reporting and methodological quality were assessed using the Joanna Briggs Institute tool to prevalence studies. Results: Our review identified seven studies published between 2002 e 2017, including 1354 participants, especially pregnant women. All studies presented at least one quality limitation, mainly regarding the sampling method (i.e., convenience) and small sample size. The prevalence of iodine deficiency ranged among studies from 16% to 62%. In contrast, the meta-analysis identified a mean prevalence of 40% (95% confidence interval, CI 37%-43%) for pregnant women and 13% (95% CI 4%-24%) for non-pregnant women. Cumulative meta-analysis suggests a tendency of higher iodine deficiency prevalence from 2018 in pregnant women. Conclusions: Although this systematic review identified studies with poor methodological and reporting quality, a high prevalence of iodine deficiency was identified in pregnant women, reinforcing the importance of national nutritional policies for monitoring iodine status in this population. Future studies should consider random probabilistic sampling, appropriate sample size, and pre-defined subgroup analysis to adequately inform the prevalence of iodine deficiency and associated factors in women of childbearing age and support health policies.

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How to Cite
Lucchetta R. C., Gini A. L. R., Cavicchioli S. de A., Forgerini M., Varallo F. R., de Nadai M. N., Fernandez-Llimós F., & Mastroianni P. de C. (2021). Iodine deficiency in women of childbearing age in Brazil: systematic review and meta-analysis. Vitae, 28(2).