Effects of iodine supplementation on thyroid function parameter: Systematic review and meta-analysis.

BACKGROUND: Supplementation is an alternative with potential benefits for the prevention of iodine deficiency in pregnancy. OBJECTIVE: To evaluate the effects of iodine supplementation on maternal thyroid hormone concentrations and iodine status during and/or before pregnancy. METHODS: The review was conducted based on the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA). The search was conducted in the databases: Cochrane, Embase, Pubmed/MEDLINE and Scopus. Studies involving pregnant women of all trimesters who received oral iodine supplementation were included. Study selection was performed in the Rayyan program. Risk of bias was assessed by the Joanna Briggs Institute tool. Meta-analysis was performed in R software version 4.0.4. RESULTS: Eleven articles with low and moderate risk of bias were included. According to the results of the meta-analysis, supplementation of 200 µg/day of iodine was able to change urinary iodine concentration during pregnancy, thus contributing to adequate intake. When evaluating the period when the intervention started, the best time to start supplementation was prior to pregnancy or in early pregnancy. CONCLUSION: Daily iodine supplementation had satisfactory effects on iodine status and maternal thyroid hormone concentrations. Although supplementation with 200 µg showed positive effects on iodine status in pregnancy, some studies showed no effect. Prospero Registration: CRD42021249307 (https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=249307).

Food insecurity and its socioeconomic and health determinants in pregnant women and mothers of children under 2 years of age, during the COVID-19 pandemic: A systematic review and meta-analysis.

Background: The COVID-19 pandemic has reduced access to adequate food in terms of quality and quantity, especially for the most vulnerable population groups. The objective of this study was to evaluate the prevalence of Food Insecurity and its main socioeconomic and health determinants in pregnant women and mothers of children under 2 years of age, during the COVID-19 pandemic. Methods: This systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) and registered in the International Prospective Register of Systematic Reviews (PROSPERO) (CRD42021278033). The descriptors "Pregnant Woman", "Postpartum Women", "Breastfeeding Women", "COVID-19", "Food Insecurity", "Food Security" were combined in Scopus (Elsevier), Medline/PubMed (via National Library of Medicine), Embase (Elsevier), Web of Science and Science Direct independently by two researchers in September 2022. Original articles about Food Insecurity in households with pregnant women and mothers of children under 2 years of age during the COVID-19 pandemic were included. The meta-analysis of the prevalence of Food Insecurity was conducted using the RStudio software (4.0.4). Results: The initial search resulted in 539 records, and 10 articles met the proposed criteria and were included in this review. The prevalence of Food Insecurity ranged from 11.5 to 80.3% and in the meta-analysis it was 51% (IC: 30-71) (I 2 = 100.0%). The main socioeconomic and health determinants were ethnicity, domain language, low education, low income, informal employment, unemployment, occurrence of mental disorders, domestic violence, in addition to the unavailability of food in markets and lack of transport. The inclusion of studies with data collection by telephone stands out as a limitation, due to the non-inclusion of vulnerable groups without access to this means of communication. Conclusion: It is necessary to implement and strengthen specific public policies for the maternal and child group with the objective of protecting and strengthening the rights of women to maintain the physical and mental integrity of this group and guarantee Food Security.

Correlation Between Drinking Water and Iodine Status: a Systematic Review and Meta-analysis.

Iodine is a micronutrient essential for maintaining normal body functioning, and the consumption depends on the distribution in the environment, and insufficient or excessive intake results in thyroid dysfunction. The purpose of this review was to evaluate the correlation between iodine concentration in drinking water and the iodine status of the population. The systematic review was conducted following the PRISMA guidelines and was registered at the International Prospective Register of Ongoing Systematic Reviews (CRD42019128308). A literature search was conducted using MEDLINE/PUBMED (National Library of Medicine), LILACS (Latin-American and Caribbean Literature on Health Sciences), and Cochrane Library, June 2021. The quality of the studies was assessed by a checklist for cross-sectional studies developed by Joanna Briggs Institute. The initial search identified 121 articles, out of which ten were included in this systematic review, and five were included in the meta-analysis. Among the articles listed, six adopted cutoff points to classify the iodine content in the drinking water. The study identified median iodine concentration in drinking water from 2.2 to 617.8 µg/L and the correlation between iodine concentration in drinking water and urinary iodine concentration was 0.92, according to meta-analysis. Furthermore, the iodine status was correlated to the iodine content in water. The determination of a cutoff point can contribute to the implementation of iodine consumption control measures.

Prevalence of Excessive Iodine Intake in Pregnancy and Its Health Consequences: Systematic Review and Meta-analysis.

The objective was to estimate the prevalence of excessive iodine intake in pregnant women and to investigate the consequences for maternal-fetal health. The systematic review was based on PRISMA. The search was conducted in September 2021 in LILACS, PubMed/MEDLINE, Science Direct, and SCOPUS databases. Observational studies that assessed excessive nutritional iodine status in pregnancy diagnosed by urinary iodine concentration and associated it with biomarkers of thyroid health function were included. Study selection, data extraction, and risk of biased evaluation were performed independently. Meta-analysis was calculated using a fixed and random effect model, and heterogeneity was assessed by the chi-square test. Meta-regressions were performed to identify the causes of heterogeneity using the Knapp and Hartung test. Nine studies were included in the systematic review, and eight in the meta-analysis. The prevalence of excessive iodine intake in 10,736 pregnant women in different regions of the world was 52%. The main implications for pregnant women were hypothyroxinemia, hypothyroidism, and hyperthyroidism. For the newborn, macrosomia and thyroid dysfunction. In addition, drinking water with high iodine intake contributed to excessive iodine intake. Therefore, the prevalence of iodine excess was 52%, with high heterogeneity among studies, explained by trimester of gestation and FT4 level; therefore, the farther the trimester of gestation and the lower the FT4, the higher the prevalence of iodine excess. PROSPERO Registration: CRD420206467 ( https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=206467 ).

Is Dietary Iodine Intake Excessive According to the Theoretical Model of Healthy Dietary Intake Pattern in Pregnant Women and Schoolchildren: Water, Salt, or Food?

Introduction: Iodine deficiency during pregnancy can cause hypothyroidism and goiter; in schoolchildren, it can cause reduced intelligence quotient. In excess, iodine can cause thyroiditis, goiter, and Hashimoto's hypothyroidism. Currently, schoolchildren and pregnant women are classified as risk groups for excessive iodine intake and iodine deficiency, respectively. Thus, determining iodine from all sources of consumption is important for intervention planning. Objective: To construct a theoretical model for the iodine intake of schoolchildren and pregnant women of a city in the Zona da Mata Mineira region, considering a healthy diet, salt consumption and water intake. Methodology: The dietary iodine intake of pregnant women was analyzed based on a dietary iodine table compiled from an international database. A dietary plan was prepared following the Brazilian Food Guide. Iodine concentration of different salt brands sold in local establishments was checked, and drinking water samples from healthcare facilities were analyzed. A descriptive and exploratory statistical analysis was performed and the results were presented in absolute and relative frequencies, and measures of central tendency and dispersion. Results: According to the proposed diet, pregnant women and schoolchildren would have a daily intake of 71.6 µg and 71 µg, respectively. Thirteen salt brands were evaluated, 69.2% complied with the legislation and the mean iodine content was 29.88 mg. The mean concentration of iodine in water was 25 µg iodine/liter and 14 µg iodine/liter, respectively, in summer and autumn. Considering the intake of food, salt, and drinking water according to the proposed dietary plan, the daily intake for pregnant women would be 279.5 and 253.5 µg for schoolchildren. Conclusion: The daily iodine intake of schoolchildren and pregnant women according to this theoretical model was excessive, considering a healthy dietary pattern. This theoretical model can guide actions and public policies aimed at targeting all forms of iodine intake.

[Critical analysis of the indicators of the nutritional status of iodine in individuals and populations: a systematic review]. / Análise crítica dos indicadores do estado nutricional de iodo em indivíduos e populações: uma revisão sistemática.

The scope of this article is to evaluate the potentialities of indicators of the nutritional status of iodine in individuals or populations. The review was based on PRISMA. The search for articles occurred in January 2019, in the Pubmed, Scopus and LILACS databases, using the key words: indicators AND nutritional status AND iodine. The selection followed the stages of excluding the duplicates, reading the titles, abstracts and analyses in full. The methodological quality of the studies was evaluated by the Downs and Black instrument. A total of 178 studies were identified and 20 were included. Urinary Iodine Concentration (UIC) was analyzed in 65% of the studies and was considered the best indicator to evaluate the nutritional status of iodine in the population. Thyroglobulin was determined in 20% of the studies and reflected the pre-existing state of iodine. Thyroid stimulating hormone was verified in 45% of the articles and was important for the surveillance of iodine deficiency among newborns. Only one study evaluated capillary iodine, useful for analyzing long-term dietary intake. In the evaluation of methodological quality, the lowest score was 12 and the highest 16, in 17 possible points. The use of UIC is recommended for the diagnosis of deficiency and excess of iodine in the population.

O objetivo deste artigo é avaliar as potencialidades dos indicadores do estado nutricional de iodo em indivíduos ou populações. A revisão foi baseada no PRISMA. A busca pelos artigos ocorreu em janeiro de 2019, nas bases Pubmed, Scopus e LILACS, utilizando a combinação "indicadores AND estado nutricional AND iodo". A seleção seguiu as etapas de exclusão dos duplicados, leitura de títulos e resumos e análise na íntegra. A qualidade metodológica dos estudos foi avaliada pelo instrumento de Downs e Black. Foram identificados 178 estudos e 20 foram incluídos. A Concentração Urinária de Iodo (CUI) foi analisada em 65% dos estudos e foi considerado o melhor indicador para avaliar o estado nutricional de iodo populacional. A tiroglobulina foi determinada em 20% dos estudos e refletiu o estado de iodo pregresso. O hormônio estimulante da tireoide foi verificado em 45% dos artigos e mostrou-se sensível para a vigilância de deficiência de iodo em recém-nascidos. Apenas um estudo avaliou o iodo no cabelo, útil para analisar a ingestão dietética em longo prazo. Na avaliação da qualidade metodológica, a menor pontuação foi 12, e a maior 16, em 17 pontos possíveis. Para diagnóstico de deficiência e excesso de iodo na população, recomenda-se a CUI.

Análise crítica dos indicadores do estado nutricional de iodo em indivíduos e populações: uma revisão sistemática / Critical analysis of the indicators of the nutritional status of iodine in individuals and populations: a systematic review

Resumo O objetivo deste artigo é avaliar as potencialidades dos indicadores do estado nutricional de iodo em indivíduos ou populações. A revisão foi baseada no PRISMA. A busca pelos artigos ocorreu em janeiro de 2019, nas bases Pubmed, Scopus e LILACS, utilizando a combinação "indicadores AND estado nutricional AND iodo". A seleção seguiu as etapas de exclusão dos duplicados, leitura de títulos e resumos e análise na íntegra. A qualidade metodológica dos estudos foi avaliada pelo instrumento de Downs e Black. Foram identificados 178 estudos e 20 foram incluídos. A Concentração Urinária de Iodo (CUI) foi analisada em 65% dos estudos e foi considerado o melhor indicador para avaliar o estado nutricional de iodo populacional. A tiroglobulina foi determinada em 20% dos estudos e refletiu o estado de iodo pregresso. O hormônio estimulante da tireoide foi verificado em 45% dos artigos e mostrou-se sensível para a vigilância de deficiência de iodo em recém-nascidos. Apenas um estudo avaliou o iodo no cabelo, útil para analisar a ingestão dietética em longo prazo. Na avaliação da qualidade metodológica, a menor pontuação foi 12, e a maior 16, em 17 pontos possíveis. Para diagnóstico de deficiência e excesso de iodo na população, recomenda-se a CUI.

Abstract The scope of this article is to evaluate the potentialities of indicators of the nutritional status of iodine in individuals or populations. The review was based on PRISMA. The search for articles occurred in January 2019, in the Pubmed, Scopus and LILACS databases, using the key words: indicators AND nutritional status AND iodine. The selection followed the stages of excluding the duplicates, reading the titles, abstracts and analyses in full. The methodological quality of the studies was evaluated by the Downs and Black instrument. A total of 178 studies were identified and 20 were included. Urinary Iodine Concentration (UIC) was analyzed in 65% of the studies and was considered the best indicator to evaluate the nutritional status of iodine in the population. Thyroglobulin was determined in 20% of the studies and reflected the pre-existing state of iodine. Thyroid stimulating hormone was verified in 45% of the articles and was important for the surveillance of iodine deficiency among newborns. Only one study evaluated capillary iodine, useful for analyzing long-term dietary intake. In the evaluation of methodological quality, the lowest score was 12 and the highest 16, in 17 possible points. The use of UIC is recommended for the diagnosis of deficiency and excess of iodine in the population.

Assessment of the Impact of Salt Iodisation Programmes on Urinary Iodine Concentrations and Goitre Rates: A Systematic Review.

INTRODUCTION: Two main strategies are currently recommended for the prevention and control of iodine deficiency in the world: implementation of universal salt iodisation programmes and permanent monitoring of iodine consumption by the population. Although iodine intake and coverage iodised salt have increased in the world population, iodine deficiency disorders (IDDs) may still be a public health problem in a few countries or communities. OBJECTIVE: To assess the impact of salt iodisation programmes on urinary iodine concentrations and goitre rates in the world population. Methodology. A systematic review based on the PRISMA method. We obtained articles from Scopus, Science Direct, MEDLINE databases, and other sources between March and April 2020, without limitation of dates. "Iodisation" AND "urinary iodine concentrations" AND "goitre" in English, Portuguese, and Spanish without filters and clinical trial, case-control, and cross-sectional studies were included in this review. RESULTS: Of 479 abstracts, twenty-three were eligible. Coverage on iodised salt was in the range of 16 to 98%, and 11 studies had been sufficient, whilst eight studies had adequate iodine concentration in salt and three excess. 81.8% of studies that had an adequate median of UIC had a good impact in their respective salt iodisation programmes. CONCLUSION: After 18 years of salt iodisation programme implementation in the 13 countries, the majority achieved sustaining elimination of IDD whilst all had adequate median UIC; however, more detailed studies are still needed to confirm that all communities are equally protected of IDD.

Implications of iodine deficiency by gestational trimester: a systematic review.

As pregnant women are susceptible to changes in iodine, which can cause miscarriage, goiter, thyroid nodules, hypothyroidism, in addition to fetal neurological impairment or development. The aim of this study was to verify the implications of the iodine alteration in each gestational trimester and its consequences of physiological justification. The review was based on PRISMA. Searching for articles that took place in March 2020 without delimiting data. As bases consulted were the Clinical Trials, Cochrane Library, Lilacs and Medline (PubMed). The descriptors were combined as follows: "pregnancy" AND "iodine deficiency". Articles that addressed iodine deficiency and its implications were included. The selection followed the steps of reading the titles, abstracts and full articles. To assess the methodological quality of the studies, the STROBE Instruction instrument was used. The research resulted in 1,266 studies and 11 were included. In assessing methodological quality, the lowest score was and the maximum 20. According to studies, the fourth most affected by iodine loss are the second and third, it is possible to increase the volume and pneumatic nodules, subclinical hypothyroidism, pre-eclampsia, among others. The damages caused by iodine deficiency in the first or second trimester are still reversible, therefore, they need to be diagnosed early, to guarantee an iodic homeostasis and prevent damage to the health of the mother-child binomial.

[Factors associated with the nutritional status of iodine in the maternal-infant group: a systematic review]. / Fatores associados ao estado nutricional de iodo no grupo materno-infantil: uma revisão sistemática.

This article sets out to identify the socio-demographic and nutritional factors associated with the nutritional status of iodine in the maternal-infant group. The review was based on the Prisma method and the Medline (PubMed), Scopus and Lilacs databases were consulted. The search was conducted in December 2018, using the key words nutritional status, iodine, infant, pregnant and lactating. The selection followed the stages of excluding duplicated articles, reading the titles, abstracts and texts in full. A total of 1,500 studies were identified and 26 met the inclusion criteria. The methodological quality of the studies was evaluated using the questionnaire proposed by Downs and Black. There was an association between the sociodemographic factors of income, education, maternal and gestational age, uniformity and place of residence in rural or urban areas with the nutritional state of iodine. In relation to dietary factors, the consumption of supplements, iodized salt and dietary sources of iodine, especially dairy products, play a protective role to avoid the deficiency. It is necessary to create more specific and effective strategies that address all the factors that affect the nutritional state of iodine to avoid the disorders resulting from the deficiency.

O objetivo deste artigo é identificar os fatores sociodemográficos e alimentares associados ao estado nutricional de iodo do grupo materno-infantil. A revisão foi baseada no método PRISMA. As bases consultadas foram: Medline (PubMed), Scopus e Lilacs. A busca ocorreu em dezembro de 2018, utilizando os descritores estado nutricional, iodo, lactente, gestante e lactante. A seleção seguiu as etapas de exclusão dos duplicados, leitura dos títulos, resumos e análise na íntegra. Foram identificados 1.500 estudos e 26 contemplaram os critérios de inclusão. A qualidade metodológica dos estudos foi avaliada pelo questionário proposto por Downs e Black. Houve associação entre os fatores sociodemográficos renda, escolaridade, idade materna e gestacional, paridade e local de residência rural ou urbano com o estado nutricional de iodo. Já em relação aos fatores alimentares, o consumo de suplementos, sal iodado e alimentos fontes de iodo, em especial os produtos lácteos, exercem papel protetor contra a deficiência. É preciso criar estratégias mais específicas, efetivas e que contemplem todos esses fatores que afetam o estado nutricional de iodo para evitar as desordens provocadas pela deficiência.

Fatores associados ao estado nutricional de iodo no grupo materno-infantil: uma revisão sistemática / Factors associated with the nutritional status of iodine in the maternal-infant group: a systematic review

Resumo O objetivo deste artigo é identificar os fatores sociodemográficos e alimentares associados ao estado nutricional de iodo do grupo materno-infantil. A revisão foi baseada no método PRISMA. As bases consultadas foram: Medline (PubMed), Scopus e Lilacs. A busca ocorreu em dezembro de 2018, utilizando os descritores estado nutricional, iodo, lactente, gestante e lactante. A seleção seguiu as etapas de exclusão dos duplicados, leitura dos títulos, resumos e análise na íntegra. Foram identificados 1.500 estudos e 26 contemplaram os critérios de inclusão. A qualidade metodológica dos estudos foi avaliada pelo questionário proposto por Downs e Black. Houve associação entre os fatores sociodemográficos renda, escolaridade, idade materna e gestacional, paridade e local de residência rural ou urbano com o estado nutricional de iodo. Já em relação aos fatores alimentares, o consumo de suplementos, sal iodado e alimentos fontes de iodo, em especial os produtos lácteos, exercem papel protetor contra a deficiência. É preciso criar estratégias mais específicas, efetivas e que contemplem todos esses fatores que afetam o estado nutricional de iodo para evitar as desordens provocadas pela deficiência.

Abstract This article sets out to identify the socio-demographic and nutritional factors associated with the nutritional status of iodine in the maternal-infant group. The review was based on the Prisma method and the Medline (PubMed), Scopus and Lilacs databases were consulted. The search was conducted in December 2018, using the key words nutritional status, iodine, infant, pregnant and lactating. The selection followed the stages of excluding duplicated articles, reading the titles, abstracts and texts in full. A total of 1,500 studies were identified and 26 met the inclusion criteria. The methodological quality of the studies was evaluated using the questionnaire proposed by Downs and Black. There was an association between the sociodemographic factors of income, education, maternal and gestational age, uniformity and place of residence in rural or urban areas with the nutritional state of iodine. In relation to dietary factors, the consumption of supplements, iodized salt and dietary sources of iodine, especially dairy products, play a protective role to avoid the deficiency. It is necessary to create more specific and effective strategies that address all the factors that affect the nutritional state of iodine to avoid the disorders resulting from the deficiency.

Implications of iodine deficiency by gestational trimester: a systematic review

ABSTRACT As pregnant women are susceptible to changes in iodine, which can cause miscarriage, goiter, thyroid nodules, hypothyroidism, in addition to fetal neurological impairment or development. The aim of this study was to verify the implications of the iodine alteration in each gestational trimester and its consequences of physiological justification. The review was based on PRISMA. Searching for articles that took place in March 2020 without delimiting data. As bases consulted were the Clinical Trials, Cochrane Library, Lilacs and Medline (PubMed). The descriptors were combined as follows: "pregnancy" AND "iodine deficiency". Articles that addressed iodine deficiency and its implications were included. The selection followed the steps of reading the titles, abstracts and full articles. To assess the methodological quality of the studies, the STROBE Instruction instrument was used. The research resulted in 1,266 studies and 11 were included. In assessing methodological quality, the lowest score was and the maximum 20. According to studies, the fourth most affected by iodine loss are the second and third, it is possible to increase the volume and pneumatic nodules, subclinical hypothyroidism, pre-eclampsia, among others. The damages caused by iodine deficiency in the first or second trimester are still reversible, therefore, they need to be diagnosed early, to guarantee an iodic homeostasis and prevent damage to the health of the mother-child binomial.