Características de las concentraciones elevadas de yoduria en escolares y adolescentes de Colombia / Characteristics of the high ioduria concentrations in schoolchildren and adolescents in Colombia

RESUMEN Objetivos: Determinar las características de las concentraciones elevadas de yoduria en escolares y adolescentes de Colombia. Materiales y métodos: Análisis secundario de la Encuesta Nacional de la Situación Nutricional en Colombia del 2015 en participantes de 5 a 17 años que incluyó la medición de yoduria. Los criterios para medir el estado nutricional del yodo se basaron en la mediana de la concentración de yodo urinario en µg/L definido por la Organización Mundial de la Salud (OMS), donde valores <100 son considerados como deficientes, entre 100-199 adecuada, 200-299 arriba de los requerimientos y >300 excesiva. Se realizaron además mediciones de razón de probabilidades a través de un análisis de regresión logística. Resultados: La mediana de yoduria nacional para escolares y adolescentes fue 406,8 µg/L y 410,8 μg/L respectivamente, mayor en el área urbana (410,5 µg/L); en la región Atlántica se encontró el mayor nivel para escolares (423,7 µg/L) y en la central para adolescentes (427,7 µg/L). El 4,4% de escolares y el 2,2% de adolescentes presentaron deficiencia y en más del 75% de la población, hubo ingesta excesiva de yodo. Los factores asociados a la ingesta excesiva de yodo en escolares fueron edad, etnia, región e índice de riqueza; y para adolescentes el sexo y área geográfica. Conclusiones: Las concentraciones de yoduria en escolares y adolescentes colombianos es superior al adecuado según OMS, la deficiencia es muy baja y se presenta un grave problema de salud pública por ingesta excesiva de yodo en tres cuartas partes de la población.

ABSTRACT Objetives: To determine the characteristics of high ioduria concentrations in schoolchildren and adolescents in Colombia. Materials and methods: Secondary analysis of the 2015 National Survey of the Nutritional Situation in Colombia in participants aged 5 to 17 years, which included the measurement of ioduria. The criteria to measure the nutritional status of iodine were based on the median urinary iodine concentration in µg / L defined by the World Health Organization (WHO), where values ​​<100 are considered deficient, between 100-199 adequate, 200-299 above the requirements and> 300 excessive. Odds ratio measurements were also performed through logistic regression analysis. Results: The national median iodine for schoolchildren and adolescents was 406.8 µg / L and 410.8 µg / L respectively, higher in the urban area (410.5 µg / L), in the Atlantic region the highest level was found for schoolchildren (423.7 µg / L) and in the central for adolescents (427.7 µg / L). 4.4% of schoolchildren and 2.2% of adolescents presented deficiency and in more than 75% of the population, there was excessive intake of iodine. The factors associated with excessive iodine intake in schoolchildren were age, ethnicity, region and wealth index, and for adolescents gender and geographic area. Conclusions: The iodine concentrations in Colombian schoolchildren and adolescents are higher than adequate according to WHO, the deficiency is very low and a serious public health problem occurs due to excessive iodine intake in three-quarters of the population.

Características de las concentraciones elevadas de yoduria en escolares y adolescentes de Colombia / Characteristics of the high ioduria concentrations in schoolchildren and adolescents in Colombia

RESUMEN Objetivos: Determinar las características de las concentraciones elevadas de yoduria en escolares y adolescentes de Colombia. Materiales y métodos: Análisis secundario de la Encuesta Nacional de la Situación Nutricional en Colombia del 2015 en participantes de 5 a 17 años que incluyó la medición de yoduria. Los criterios para medir el estado nutricional del yodo se basaron en la mediana de la concentración de yodo urinario en µg/L definido por la Organización Mundial de la Salud (OMS), donde valores <100 son considerados como deficientes, entre 100-199 adecuada, 200-299 arriba de los requerimientos y >300 excesiva. Se realizaron además mediciones de razón de probabilidades a través de un análisis de regresión logística. Resultados: La mediana de yoduria nacional para escolares y adolescentes fue 406,8 µg/L y 410,8 μg/L respectivamente, mayor en el área urbana (410,5 µg/L); en la región Atlántica se encontró el mayor nivel para escolares (423,7 µg/L) y en la central para adolescentes (427,7 µg/L). El 4,4% de escolares y el 2,2% de adolescentes presentaron deficiencia y en más del 75% de la población, hubo ingesta excesiva de yodo. Los factores asociados a la ingesta excesiva de yodo en escolares fueron edad, etnia, región e índice de riqueza; y para adolescentes el sexo y área geográfica. Conclusiones: Las concentraciones de yoduria en escolares y adolescentes colombianos es superior al adecuado según OMS, la deficiencia es muy baja y se presenta un grave problema de salud pública por ingesta excesiva de yodo en tres cuartas partes de la población.

ABSTRACT Objetives: To determine the characteristics of high ioduria concentrations in schoolchildren and adolescents in Colombia. Materials and methods: Secondary analysis of the 2015 National Survey of the Nutritional Situation in Colombia in participants aged 5 to 17 years, which included the measurement of ioduria. The criteria to measure the nutritional status of iodine were based on the median urinary iodine concentration in µg / L defined by the World Health Organization (WHO), where values ​​<100 are considered deficient, between 100-199 adequate, 200-299 above the requirements and> 300 excessive. Odds ratio measurements were also performed through logistic regression analysis. Results: The national median iodine for schoolchildren and adolescents was 406.8 µg / L and 410.8 µg / L respectively, higher in the urban area (410.5 µg / L), in the Atlantic region the highest level was found for schoolchildren (423.7 µg / L) and in the central for adolescents (427.7 µg / L). 4.4% of schoolchildren and 2.2% of adolescents presented deficiency and in more than 75% of the population, there was excessive intake of iodine. The factors associated with excessive iodine intake in schoolchildren were age, ethnicity, region and wealth index, and for adolescents gender and geographic area. Conclusions: The iodine concentrations in Colombian schoolchildren and adolescents are higher than adequate according to WHO, the deficiency is very low and a serious public health problem occurs due to excessive iodine intake in three-quarters of the population.

Correlação entre níveis de iodo na urina e alterações anatomopatológicas em tireoide / Correlation between iodine urinary levels and pathological changes in thyroid glands

OBJETIVOS: Determinar o aporte nutricional de iodo na população estudada e correlacionar os níveis de iodo encontrados em amostras casuais de urina (iodúria) com alterações anatomopatológicas observadas nas tireoides dessa população. MATERIAIS E MÉTODOS: Determinou-se a iodúria em 30 amostras casuais de urina e realizou-se o estudo anatomopatológico de 55 tireoides colhidas de cadáveres que deram entrada no Departamento Médico Legal de Vitória, Espírito Santo, Brasil, no período de maio a agosto de 2011. RESULTADOS: Em 29 amostras de urina (96,7%) encontrou-se iodúria acima do limite máximo preconizado pela Organização Mundial da Saúde (OMS) de 300 µg/L. Em 14 tireoides (25,5%) foi identificada a presença de quadros histológicos compatíveis com tireoidite. Níveis mais elevados de iodo na urina foram observados no sexo feminino e nos casos de tireoides com presença de achados inflamatórios (tireoidites). CONCLUSÕES: Podemos concluir que na população estudada houve um excesso de iodo em seu aporte nutricional e uma maior incidência de quadros inflamatórios tireoidianos.

OBJECTIVES: To determine iodine nutrition in the population and to correlate levels of iodine found in random samples of urine with pathological changes observed in thyroids collected in this population. MATERIALS AND METHODS: Urinary iodine was determined in 30 random samples of urine and the pathological study was carried out in 55 thyroid glands from corpses received by the Department of Forensic Medicine of Vitória, Espírito Santo, Brazil from May to August 2011. RESULTS: In 29 urine samples (96.7%) urinary iodine was above the maximum limit recommended by the World Health Organization (WHO), of 300 mg/L. Fourteen thyroids (25.5%) showed the presence of histological changes compatible with thyroiditis. Higher levels of iodine in urine were observed in females and in of thyroid that showed inflammation (thyroiditis). CONCLUSIONS: We conclude that, in this population, there is excess iodine intake, and greater incidence of inflammatory thyroid disease.

Study on the prevalence of thyroid diseases during pregnancy in excess and sufficient water iodine area in Jiangsu Province / 中华内分泌代谢杂志

Objective To study the prevalence of thyroid disease in pregnant women living in both excess and sufficient water iodine area of in Jiangsu Province,and to establish an epidemiological database of thyroid disorders among pregnant women in different water iodine area in Jiangsu Province in order to guide our clinical practise.Methods Fengxian and Suining of Xuzhou were selected as excess and sufficient water iodine region.All the 439 pregnant women within the first trimester were enrolled in our study.The name,age,and previous history were recorded on questionnaire.The samples of fasting blood were obtained.Serum parameters such as free triiodothyronine ( FT3 ),free thyroxine ( FT4 ),total thyroxine ( TT4 ),thyrotropic stimulating hormone ( TSH ),and thyroid peroxidase (TPOAb) were measured by electrochemiluminescence assay.The data of the eligible 396 subjects were stored and analyzed by Epidata after excluding subjects with previous thyroid dysfuncion,renal disease,heart disease,and pregnancy-induced hypertension syndrome.Results Among the 396 subjects,197 women ( 49.7％ ) had thyroid disorders. The prevalence of hyperthyroidism, subclinical hyperthyroidism, hypothyroidism, subclinical hypothyroidism,hypothyroxinaemia,and thyroid autoimmunity were 0.5％,6.3％,3.3％,29.3％,9.3％,and 1.0％,respectively.The prevalence of subclinical hypothyroidism was significantly higher in excess water iodine region (32.4％) than that in sufficient water iodine area ( 19.6％ ),while the prevalence of other types of thyroid diseases such as subclinical hyperthyroidism,hyperthyroidism,hypothyroidism,hypothyroxinaemia,and TPOAbpositive cases in either excess or sufficient water iodine regions was not different.Conclusions Subclinical hyperthyridism,hypothyroxinaemia,and subclinical hypothyroidism are the main thyroid disorders in pregnant women in both excess and sufficient water iodine area.The prevalence of subclinical hypothyroidism increases obviously in excess water iodine region,indicating the relationship between thyroid disease and high iodine intake.

A comparative study on thyroid function during late pregnancy and of fertile women in iodine excess area / 中华内分泌代谢杂志

To explore the influences of pregnancy and iodine intake on thyroid function and immune functions, 210 pregnant women and 290 fertile women were chosen from iodine excess area, and the average ages of them were (27. 69±4. 73 )and (30. 62±6. 01 )years respectively. Fasting blood and urine were collected in the morning. The urinary iodine level was determined by arsenic-cerium catalytic contact. Serum free triiodothyronine ( FT3 ), free thyroxine ( FT4 ), and sensitive thyroid-stimulating hormone ( sTSH ) levels were measured by chemiluminescence.Thyroid peroxidase antibody (TPOAb)and thyroglobulin antibody (TGAb)were measured by radioimmunoassay. The median urinary iodine in the pregnant and fertile women were I 240. 70 and 949. 21 μg/L, respectively. There were 84. 3% pregnant women and 81.0% fertile women admitting excess iodine intake. The prevalence of overall thyroid diseases was 22. 9% in the pregnant women and 30. 3% in the fertile women. The prevalence of hyperthyroidism,subclinical hyperthyroidism, hypothyroidism, and subclinical hypothyroidism was0. 5%, 1.9%, 0. 5%, and 20. 0% in the former group, and 2. 8%, 0. 3%, 0. 3%, and 26. 9% in the latter. Both FT3 and FT4 levels of the pregnant women were lower than those of fertile women [(4. 03±0. 59 vs 4. 71 ± 1.04)pmol/L, ( 13. 35 ± 1.59 vs 14. 27 ±3.63 )pmol/L,both P＜0. 01], and the positive rate of TGAb of pregnant women was also lower than that of fertile women (7. 1% vs14. 1%, P=0. 014). The prevalence of thyroid diseases and positive rate of thyroid autoantibodies is high in women with excess iodine intake. Compared with fertile women, pregnancy may lead to decreas~s in level of thyroid hormones and positive rate of TGAb. Their iodine intake should be controlled, and the thyroid function and autoimmunity antibodies should be monitored.

Iodine nutrition in Brazil: where do we stand? / Iodo nutricional no Brasil: como estamos?

Brazilian legislation, since 1955, failed to achieve its objectives because the issue was not properly addressed: iodized salt was only available in endemic areas, at a low amount of 10 mg Iodine/kg salt. Lack of surveillance and cooperation were common errors. From 1982 to 1992, the INAN distributed potassium iodate to the industry free of charge, but it was abolished in 1991. Only four years later (1995) was a new law enacted effective in determining that all salt for human use should be iodized at levels established by the Health Authorities. During the period comprising 1998 to 2004, excessive iodination of salt (40 to 100 mg/kg) could lead to an increased prevalence of chronic autoimmune thyroiditis and iodine-induced hyperthyroidism. In 2003, the content of iodine/kg of salt was lowered to 20 to 60 mg I/kg salt. A national survey of schoolchildren is currently underway and will indicate the changes required for adequate iodine in salt for human use.

A legislação para corrigir deficiência crônica de iodo no Brasil iniciou-se em 1955. O sal iodado seria distribuído somente em áreas endêmicas de bócio, com dose fixa de 10 mg Iodo/kg de sal. Na década de 1982 a 1992, o Instituto Nacional de Alimentação e Nutrição assumiu o Programa Nacional para a Deficiência Crônica de Iodo e forneceu o iodato de potássio a todos os produtores de sal. Em 1992, o INAN foi dissolvido. Nova legislação foi promulgada em 1995. A Anvisa ficou encarregada de supervisionar o teor de iodo em amostras de sal. No período de 1998 a 2004, o teor de iodo no sal foi elevado para 40 a 100 mg I/kg de sal. O excesso nutricional de iodo na população possivelmente aumentou a prevalência de tireoidite de Hashimoto e hipertireoidismo. Inquérito epidemiológico nacional (PNAISAL) em escolares, em execução, indicará as futuras determinações para a adição de iodo no sal.