Degree Of Iodine Deficiency Research Articles

Iodine intake and neonatal thyroid function: A never-ending story

Iodine deficiency in pregnant women can lead to abortion, dysgravidy, intrauterine growth restriction, premature birth, low birth weight, which places the pregnant woman in a group with increased vulnerability to the lack of adequate amounts of iodine. Iodine deficiency in pregnancy can lead to increased perinatal and infant mortality and the prevalence of congenital anomalies. All these aspects shed new light on the many side effects of iodine deficiency during pregnancy. The present paper aligns with the general trend of assessing the maternal-fetal thyroid hormone status and establishing the most accurate indicators for its quantification and taking into account the degree of iodine deficiency and prematurity.

Стан йодного забезпечення дітей та жінок репродуктивного віку в західному регіоні України

Актуальність. В Україні за останні роки спостерігається зростання частоти тиреоїдної патології. Абсолютна кількість випадків захворювання щитоподібної залози за останні 10 років зросла з 689 000 до 1 486 000, згідно з даними щодо поширення, що становить 941,6 і 4210,4 випадку на 100 000 населення відповідно. Частота патології щитоподібної залози (станом на 01.01.2018) становить 46 % від усіх ендокринологічних захворювань і посідає перше місце серед них. Основною причиною є незбалансованість мікроелементного і вітамінного складу в раціоні на тлі погіршення екологічної ситуації та техногенного забруднення довкілля. Метою дослідження було оцінити ступінь йодного дефіциту в населення західного регіону України та надати теоретичне обґрунтування подальшого подолання йододефіцитних станів. Матеріали та методи. Вивчення стану йодного забезпечення населення проводили серед вагітних жінок у першому триместрі вагітності (19–44 роки) та дітей шкільного віку (12–14 років), які проживають у західному регіоні України. Йодне забезпечення оцінювали з використанням неонатального скринінгу концентрації тиреотропного гормону в новонароджених, даних щодо частоти зоба за результатами пальпаторного обстеження, ультрасонографічного обстеження щитоподібної залози та медіани екскреції йоду з сечею. Результати. За даними неонатального скринінгу частота гіпертиреотропінемії становила в середньому 3,52 ± 0,30 % в популяції, що відповідає легкому ступеню йодної недостатності. За результатами ультрасонографічного обстеження щитоподібної залози частота виявлення зоба в дітей становить 38 %, а у вагітних жінок — 36 %, що є характерним для тяжкого ступеня йодного дефіциту. Результати визначення медіани йодурії в дітей показали недостатнє йодне забезпечення в 20 %, концентрація йоду в сечі в середньому становила 99,69 ± 35,42 мкг/л. У 30 % дітей спостерігалось надлишкове надходження йоду в організм, та 50 % обстежених дітей мали оптимальне забезпечення йодом. Нестачу йоду в раціоні вагітних було виявлено в 43,3 % обстежених (медіана йодурії 81,96 ± 42,53 мкг/л). У 26,7 % вагітних концентрація йоду в сечі відповідала нормальному інтервалу, надлишкове надходження йоду в організм при медіані понад 230 мкг/л було виявлене в 30 % вагітних. Висновки. Оцінка йодного забезпечення населення західного регіону України свідчить про тяжкий ступінь йодної недостатності, що вимагає термінового впровадження загальнонаціональної програми профілактики.

Состояние йодного обеспечения детей препубертатного возраста, проживающих на территории Северной Буковины

Актуальность. На Буковине в зависимости от климатогеографических зон наблюдается йодная недостаточность легкой и средней степени тяжести. Оценка экскреции неорганического йода с мочой позволяет проводить мониторинг эпидемиологической ситуации по тяжести йодного дефицита в регионе. Цель — оценить показатели экскреции йода у детей препубертатного возраста, проживающих на территории Северной Буковины (Черновицкая область). Материалы и методы. В рамках 20-кластерного анализа распространенности зоба среди детского населения Черновицкой области обследованы 1973 ребенка в возрасте от 7 до 12 лет и определена концентрация неорганического йода в разовой порции мочи у 197 детей. Полученные результаты обработаны методом статистического вариационного и корреляционного анализа. Результаты. Обследование мануально-пальпаторным методом показало значительную частоту зоба среди детей Буковины — 17,6%. Тиреомегалия среди детей референтной группы зарегистрирована в 15,1 % случаев. Медиана йодурии в обследованной популяции в целом составляет 60,4 мкг/л. В среднем распространенность йодного дефицита составила 59,70 ± 1,82 %, частота тяжелой йодной недостаточности не превысила 5,22 ± 1,30 %. Анализируя степень йодного обеспечения организма детей в зависимости от географических зон проживания, делаем вывод, что у детей, проживающих в равнинной зоне, и у детей г. Черновцов наблюдается дефицит йода легкой степени (медиана экскреции йода составляет 72,2 и 70,4 мкг/л соответственно), а у детей горных районов — йодный дефицит средней степени тяжести (медиана экскреции йода — 42,9 мкг/л). В среднем распространенность йодного дефицита составила 59,70 ± 1,82 %, а избыточного содержания йода в моче — 18,70 ± 2,49 %. Причем показатель тяжелой йодной недостаточности не превысил 5,22 ± 1,30 %. Выводы. У большинства детей, проживающих на территории Северной Буковины, медиана йодурии снижена. У 18,7 % детей показатель йодурии более 300 мкг/л, что требует дальнейшего мониторинга.

State of iodine supply in children with chronic gastroduodenitis

Objective — to study the state of iodine supply in children with chronic gastroduodenal pathology.
 Materials and methods. The study included 23 children with chronic gastroduodenitis: 13 girls (56 %) and 10 boys (43.5 %) aged 8 to 18 years. The control group consisted of 11 children matched in age and sex. All patients underwent endoscopic examination of the upper digestive tract. H. pylori infection was tested with a rapid urease breathing test «Helik‑test». All children underwent determination of iodine level in single portions of urine using the cerium‑arsenite method Sandell‑Koltoff modified by Dunn, with the following calculation of the median.
 Results. The frequency of iodine deficiency in children with chronic gastroduodenitis was 60.9 ± 10.2 %, which significantly exceeded this parameter in the control group (8.7 ± 8.6 %; p < 0.01). A mild degree of iodine deficiency was noted in 43.5 ± 10.3 % of patients, which was also significantly higher than in the control group (9.09 ± 8.6 %; p < 0.05). Moderate iodine deficiency was observed only in children of the main group (21.7 ± 8.5 %). Severe iodine deficiency in the study was not found among all children. The median ioduria in patients was 81.9 mg/l, which was significantly lower than in children in control group (183.7 mg/l; p < 0.05). Analysis of ioduria level, taking into consideration the endoscopic picture of gastrointestinal tract lesions, showed that both in frequency (p < 0.05) and median (p < 0.05), children with a more severe inflammation of the gastric mucosa and duodenum had the worst indices of iodine supply. In children infected with H. pylori iodine deficiency was observed significantly more often (p < 0.05), the median ioduria was significantly lower (p < 0.05) than in uninfected children.
 Conclusions. In children with chronic gastroduodenal pathology, a significant frequency of iodine deficiency is revealed, which increases with the severity of inflammatory changes in the mucous membrane and the presence of H. pylori infection. Determination of the state of iodine supply in children with digestive tract pathology is advisable to prevent the development of concomitant diseases, primarily thyroid dysfunction.

To evaluate the dimensions of each lobe and total volume of thyroid gland by ultrasonography among pregnant and non pregnant women in local population, Karachi.

To evaluate the dimensions of each lobe and total volume of thyroid gland
 by ultrasonography among pregnant and non pregnant women in
 local population, Karachi.
 
 
 Abstract:
 Background: Pregnancy has an anatomical and physiological influence on the thyroid gland and it’s function. It is good to know the normal changes that occur during pregnancy. The size and volume of this gland is increased through the pregnancy and becomes visible due to iodine deficiency (ID) that can lead to goiter or may develop hypothyroidism. Objective of the study were to evaluate dimensions of both lobes and calculation of thyroid volume by using ultrasonography (USG) and to compare these parameters between pregnant and non pregnant in Karachi, Pakistan.
 Methodology: It was a clinical cross sectional study that was conducted at Gynae OPD and Radiology Department, Ojha campus, Dow university of health sciences (DUHS), Karachi from October 2016 to December 2018 through consecutive sampling. The study volunteers of reproductive age (14-45 years) were included and divided into two groups (pregnant and non-pregnant women). The dimensions of each lobe and calculation of thyroid volume were taken into the account through their standard protocol after following inclusion and exclusion criteria.
 Results: The comparisons were made on thyroid gland dimensions, ultrasound outcomes of right and left lobe length, width, depth and volume of thyroid gland. In pregnant women, right lobe length was 2.91±1.05, width was 1.54±0.41 and depth was 2.31±1.41 whereas in non pregnant women mean right lobe length was 2.50±0.97, width was 1.34±0.51 and depth was 1.68±0.98. The mean difference was considered statistically significant in pregnant women with p-value (< 0.01). In pregnant women thyroid volume was 7.02±3.21 whereas in non pregnant, it was 5.58±2.41 which was significantly increased in pregnant women with p-value (< 0.01).
 Conclusion: Therefore our study concludes that, in our population at least half of the apparently healthy pregnant females do have some degree of iodine deficiency. The volume of the gland is increased during pregnancy, suggesting iodine deficiency.
 
 Key Words: Pregnant women, non pregnant women, dimensions of thyroid gland and
 volume of thyroid gland.

Йодо- та селенодефіцит у патогенезі зобної трансформації щитоподібної залози та автоімунних тиреопатій (огляд літератури та результати власних досліджень)

У статті описано сучасний погляд на роль дефіциту йоду та селену в патогенезі захворювань щитоподібної залози (ЩЗ), зокрема її зобної трансформації та автоімунних тиреопатій. Відмічена кореляція вираженості патологічних змін зі ступенем йододефіциту. У зонах зниженого споживання йоду (<50 мкг на добу) 25-30% населення мають ту чи іншу патологію ЩЗ, серед яких найчастішою є ендемічний зоб. Другою за частотоювиникнення патологією ЩЗ є вузловий зоб, частота якого в ендемічних по зобу регіонах досягає 50-70% від усіх захворювань ЩЗ. Поєднаний дефіцит йоду і селену посилює проблему йодної недостатності, призводить до зростання частоти гіпертрофічних і гіперпластичних процесів у ЩЗ і автоімунних тиреопатій. Метою роботи було визначення вмісту йоду та селену в пацієнтів із доброякісною патологією ЩЗ. Матеріал і методи.Обстежено 81 пацієнта, віком від 19 до 69 років, яким проводили ультразвукове обстеження ЩЗ, визначали рівень екскреції йоду зі сечею церій-арсенітним методом у модифікації J.T. Dunn та ін. і рівень селену в сироватці крові спектрофлуориметричним методом. Результати. У 43,6% пацієнтів при різних видах зобної трансформації, колоїдному проліферуючому зобі, автоімунних тиреопатіях та їх поєднанні відзначено низький рівень йодної екскреції (<100 мкг/л); у 38,5% пацієнтів виявлено стабільно оптимальне йодне забезпечення (100-150 мкг/л) і в 17,9% пацієнтів — стабільно високе (>150 мкг/л). У 76,5% пацієнтів виявлено значно знижений рівень селену в крові (<80 мкг/л), у 13,6% пацієнтів — субоптимальний (81-100 мкг/л) і лише в 9,9% пацієнтів — оптимальний (101-120 мкг/л). Також відзначено, що в пацієнтів із вузловою патологією ЩЗ, автоімунними тиреопатіями та при їх поєднанні зафіксовано дефіцит селену в порівнянні з контрольною групою (ехографічно незмінена ЩЗ). Висновок. Терапія препаратами йоду та селену під контролем їх вмісту виправдана в процесі тривалого спостереження за пацієнтами із зобною трансформацією ЩЗ і автоімунними тиреопатіями.

Thyroglobulin Concentration and Maternal Iodine Status During Pregnancy: A Systematic Review and Meta-Analysis.

Background: Literature to date has been inconclusive regarding the value of thyroglobulin (Tg) as a marker of iodine status in pregnant women. This systematic review and meta-analysis is one of the first to assess whether Tg concentration accurately reflects iodine status among pregnant women. Methods: We searched MEDLINE, the Web of Science, the Cochrane Library, Scopus, and other relevant databases to identify relevant studies published in the English language, between January 1988 and December 2018. The criteria for study inclusion in the systematic review were human studies, healthy pregnant women as participants, and available data for maternal urinary iodine concentration (UIC) and Tg level. Each study was assessed for quality and risk of bias. The pooled mean Tg values, and 95% confidence intervals were estimated in a population of women with UIC <150 and UIC ≥150 μg/L during pregnancy. Potential linear or nonlinear dose-response associations between maternal UIC and Tg concentration were examined. Results: Of 814 identified studies, 25 were eligible for inclusion in the meta-analysis. Studies included were conducted in Africa, Asia, Europe, South America, and the Oceania. The pooled mean (95% confidence interval [CI]) Tg concentration in iodine-deficient pregnant women was higher than that in iodine-sufficient pregnant women (10.73 μg/L [5.65-15.82] vs. 7.34 μg/L [2.20-12.47]); a comparison of the 95% CI showed that none of these values was significantly different. No significant differences were observed in Tg concentration between the two groups in each trimester of pregnancy. Dose-response meta-analyses revealed a significant nonlinear association between maternal UIC and Tg concentration during pregnancy. Among populations of pregnant women, an inverse association was found between UIC values <100 μg/L and Tg concentration (p-linearity = 0.007; p-nonlinearity = 0.027); however, higher values of UIC were not associated with Tg concentration. Conclusions: Our meta-analysis showed that Tg concentration can be a sensitive indicator of iodine deficiency, specifically in populations of pregnant women with median UIC <100 μg/L. Further studies are warranted to determine the sensitivity of Tg at different degrees of iodine deficiency during pregnancy.

EPIDEMIOLOGICAL INDICATOR VALUE IN THE IODINE AVAILABILITY ASSESSMENT — EVIDENCE FROM THE REGIONS OF THE RUSSIAN FEDERATION

Background: In the Russian Federation, newborn screening comprises thyroid stimulating hormone determination to exclude primary congenital hypothyroidism. Screening is carried out throughout Russia. Neonatal TSH can be used to assess iodine deficiency and monitor iodine prevention programs.Objective: To assess and compare official statistical data on congenital hypothyroidism, the prevalence of hypothyroidism and iodine deficiency syndrome in children, as well as urinary iodine in the Russian regions.Materials and methods: The level of neonatal TSH was determined in 97.69% of children born in the Russian Federation in 2017. This article represents the results on the prevalence of hypothyroidism in the regions with various iodine availability. The correlation analysis was used to assess the relationship of CH incidence in newborns and iodine availability.Results: The calculated correlation coefficient, which was 0.2, reflects a weak relationship between the degree of iodine deficiency in the region and the number of newborns diagnosed with congenital hypothyroidism.Conclusions: In the Russian Federation, a law on universal salt iodization does not exist, and many regions are still in conditions of moderate or severe iodine deficiency. To assess the iodine status in these particular regions, we could use the results of newborn TSH screening

IODINE STATUS AND PATTERNS OF OXIDATIVE METABOLISM DISORDERS IN CHILDREN WITH COMMUNITY-ACQIURED PNEUMONIA FROM THE IODINE DEFICIENCY REGION

Introduction.Community‒acquired pneumonia is one of the most frequent pathologies of childhood. The severity of the course of this disease in children is due to concomitant pathology, the state of the endocrine and immune systems of the body, especially among the population living in conditions of endemic iodine deficiency.The aim of the study.To evaluate the state of the system of antioxidant protection in children with community−acquired pneumonia with iodine deficiency in conjunction with the subcellular distribution of iodine in the body.Materials and Methods.70 children with pneumonia were examined. The iodine availability of patients was determined by determining the level of ioduria, studying the intracellular distribution of iodine in the blood, assessing the state of the antioxidant defense system, lipid peroxidation, glutathione, apoptosis and the level of molecular damage.Results and Discussion. The level of iodine deficiency varied according to the severity of pneumonia: from mild (63.8 μg/L) with moderate pneumonia, to moderate (36.2 μg/L‒ moderate iodine deficiency) in severe disease. A lower content of organic iodine (by 12% and 59%, respectively) and a high concentration in the blood of inorganic iodine (21% and 48%, respectively) with mild to severe course of pneumonia was established.The severe course of pneumonia contributed to decrease in the activity of superoxide dismutase and a decrease in the redox index of glutathione against the background of an increase in the content of oxyradicals, caspase-3, intensive formation of oxidative modification of proteins, and enhancement of DNA fragmentation. The revealed changes tend to decrease depending on the severity of pneumonia.Conclusions.Indicators of oxidative stress, molecular damage and the intensity of apoptosis in children with community-acquired pneumonia correlate with the severity of the disease combined with iodine deficiency. The degree of iodine deficiency is significantly higher in children with severe pneumonia.

Maternal Different Degrees of Iodine Deficiency during Pregnant and Lactation Impair the Development of Cerebellar Pinceau in Offspring.

Aims: Iodine is critical for synthesis of thyroid hormones (TH). And iodine deficiency (ID) is one of the most significant reasons of intellectual disability and motor memory impairment, although the potential mechanisms are still under investigation. Presently, mild ID and marginal ID are largely ignored problems for women of child bearing age. Mild ID is a subtle form of TH deficiency, which shows low levels of free thyroxine (FT4) and relatively normal free triiodothyronine (FT3) or thyroid stimulation hormone (TSH). And marginal ID is a milder form of ID with decreased total T4 (TT4) but relatively normal FT3, FT4, and TSH. Therefore, we investigated the effects of maternal different degrees of ID on the development of pinceau in cerebellar purkinje cells (PCs) and studied the expression of pinceau related protein, which is crucial for the development and maturation of pinceau.Methods and Results: Three developmental iodine deficient rat models were created by feeding dam rats with an iodine-deficient diet and deionized water supplemented with potassiumiodide. Our study showed that different degrees of ID inhibited cerebellar pinceau synapse development and maturation on postnatal day (PN) 14 and PN21. What's more, mild and severe ID reduced the expression of AnkG, β4-spectrin, neurofascin186 and NrCAM on PN7, PN14, and PN21. However, marginal ID rarely altered expression of these proteins in the offspring.Conclusion: These results suggested that maternal mild and severe ID impaired the development and maturation of cerebellar pinceau, which may be attributed to the decrease of AnkG, β4-spectrin, neurofascin 186, and NrCAM. And the alteration of development and maturation in cerebellar pinceau in the offspring were also observed following maternal marginal ID, which is slighter than that of mild ID.

Quadrature of the circle

Насколько должны отличаться подходы в диагностике и лечению тироидной патологии между странами/регионами, в которых дефицит йода успешно устранен путем всеобщего йодирования соли, и теми местами, где сохраняется разной степени выраженности йодная недостаточность? Как должна изменяться диагностическая и лечебная тактика в отношении заболеваний щитовидной железы в период внедрения в стране программы всеобщего йодирования соли? Эти и другие вопросы обсуждаются в регулярной колонке "De Gustibus"

Iodine status of pregnant women in a metropolitan city which proved to be an iodine-sufficient area. Is mandatory salt iodisation enough for pregnant women?

The objective of this study was to assess the iodine status of pregnant women in a metropolitan city which was stated as iodine sufficient area after salt iodination program. This multicenter, cross-sectional study was carried out on 3543 pregnant women. Age, gestational weeks, smoking, consumption of iodized salt, dietary salt restriction, history of stillbirth, abortus and congenital malformations were questioned. Spot urine samples were analyzed for urine iodine concentration (UIC). The outcomes were: (a) median UIC in three trimesters of pregnancy and (b) frequency of ID among pregnant women. The median UIC was 73 µg/L. The median UIC was 77 µg/L (1–324), 73 µg/L (1–600) and 70 µg/L (1–1650) in three trimesters of pregnancy, respectively (p: 0.14). UIC <50 µg/L was observed in 36.6% (n: 1295) and UIC<150 µg/L was observed in 90.7% (n: 3214) of pregnant women. Only 1% (n: 34) of the pregnant women had UIC levels higher than 500 µg/L. This study showed that more than 90% of the pregnant women in this iodine-sufficient city are facing some degree of iodine deficiency during their pregnancy. A salt iodization program might be satisfactory for the non-pregnant population, but it seems to be insufficient for the pregnant population.

Comparative analysis of iodine support and functional status of pituitary-thyroid system in adolescent girls born with underweight.

Prolonged deficiency of iodine causes insufficiency of synthesis of thyroid hormones in the body of a teenage girl. If shortfalls of iodine in the body of teenage girl, thyroid gland reacts by compensatory increase in its volume that depends on the degree of iodine deficiency. Depending on the degree of iodine deficiency and due to strengthening of decompensation in pituitary-thyroid system there is a change in levels of thyrotropin and thyroid hormones in adolescent girls.

Iodine deficiency in pregnancy

Iodine is an essential micronutrient for thyroid hormone synthesis and thus is essential for the normal progression of pregnancy and for the fetus neuropsychological development. Iodine requirements increase during pregnancy for physiological changes in iodine metabolism (increased renal iodine losses, iodine transfer from maternal circulation to the fetoplacental unit and fetal iodine needs for thyroid hormone production). Therefore the iodine intake should be increased by about 50% during pregnancy and lactation and the daily dose recommended by the WHO is at least 250 µg / day corresponding to a Urinary Iodine Excretion ( UIE ) range of 150-249 µg /L. Iodine supplementation is recommended in all pregnant women , even in iodine sufficient countries or in areas where universal salt iodization has been achieved (iodized salt consumed in more than 90% of households). These measures, in fact , ensure the daily iodine intake of 150 µg / day recommended in all women of childbearing age but they are not sufficient to support the increased requirements imposed by pregnancy. Recently, even in developed countries, such as UK, USA, and Australia , moderate iodine deficiency has re-emerged as an important public health concern , likely due to a change in eating habits of the population. There are recent data that highlight how even mild degrees of iodine deficiency may adversely affect the progression of the pregnancy or the neurocognitive outcome in children. It should be emphasized that national programs of health policy must provide epidemiological surveillance measures to ensure the maintenance of iodine sufficiency over time. Because the fetal thyroid gland may be particularly sensitive to the inhibitory effect of high iodine concentrations , possible negative effects of maternal iodine supplementation during pregnancy have been hypothesized. The currently available data, however, appear to indicate a relatively low risk of these effects against the benefits derived from the adequate transfer of maternal T4 to the fetus in conditions of iodine sufficiency especially in the first trimester of gestation.

The Prevalence of Goiter and Hypothyroidism among School Children 6 Years after Introduction of a Mandatory Salt Iodination Program in a Severely Iodine-Deficient Area of the West Black Sea Region of Turkey

The objective of the current study was to determine the prevalence and the degree of iodine deficiency after mandatory salt iodization in Yığılca's school-aged children. A total of 806 school children aged 6-19 years were evaluated. The prevalence of goiter in children aged 6-12 and 13-19 years was 20.3 and 23.8%, respectively. The prevalence of hypothyroidism in children aged 6-12 and 13-19 years was 10.4 and 18.9%, respectively. The median serum free tetraiodothyronine (fT4) levels in children aged 6-12 and 13-19-years were 1.16 ng/dL and 0.91 ng/dL, respectively. The median urinary iodine concentration levels in children aged 6-12 and 13-19 years were 83 µg/l and 78 µg/l, respectively. The frequency of autoimmune thyroid disease was 2.1% in Yığılca's SAC. Goiter and iodine deficiency problems remain in rural areas of the West Black Sea Region of Turkey.

Levels of T4 and TSH in mother's blood and in cord blood at the time of delivery

Background: In conditions of maternal iodine deficiency, the frequency distribution of neonatal thyroid stimulating hormone (TSH) is shifted towards elevated values. Elevated serum TSH in the neonates indicates insufficient supply of thyroid hormones to the neonates, a major complication of iodine deficiency. Objectives: To determine the cord blood serum T4 and TSH levels and interrelationships with maternal thyroid hormones. Method: cord blood serum T4 and TSH levels of 45 consecutive newborns born at BPKIHS, Dharan, Nepal and maternal T4 and TSH levels were analyzed using ELISA based kits. Results: The mean age of mothers was 23.73± 3.86 years and average weight of the neonates was 3.038±0.45 Kg. The median levels of maternal and neonatal T4 were 1.09 ng/dl and 1.26 ng/ dl respectively. The corresponding median TSH levels were 3.71 mIU/L and 11.9 mIU/L. The maternal and neonatal levels of T4 were positively correlated. In 36 mothers who had TSH level within euthyroid range (0.3-6.2 mIU/L, Thyroid lab of BPKIHS), 22 neonates (61.11%) had TSH levels above 10 mIU/L. Among 9 mothers having TSH levels above 6.2 mIU/L, 7 (77.77%) neonates had TSH levels above 10 mIU/L. Conclusion: Overall 29 (64.44%) neonates had TSH level above 10 mIU/L which indicates mild degree of iodine deficiency. Iodine supplementation is required before pregnancy in majority of women of reproductive age. Health Renaissance, January-April 2013; Vol. 11 No.1; 6-10 DOI: http://dx.doi.org/10.3126/hren.v11i1.7593

Expression of casepase-9 protein and UCP2 gene in renal tissues of rats with different degrees of iodine deficiency

Expression of casepase-9 protein and UCP2 gene in renal tissues of rats with different degrees of iodine deficiency

What Do We Know about Iodine Supplementation in Pregnancy?

Despite major progress over the last four decades, iodine deficiency remains the leading preventable cause of mental retardation. It has been estimated that 20% of the 2 billion individuals worldwide currently at risk for iodine deficiency disorders reside in Europe (1). The study of Velasco et al. (2), published in this issue of JCEM, demonstrated that infants of Spanish mothers who had received oral 300 g potassium iodide (KI) supplements daily during pregnancy and lactation had higher Bayley Psychomotor Development scores at 3–18 months of age than infants whose mothers did not receive iodine supplements. A strength of the study was the authors’ ability to collect trimester-specific urinary iodine concentrations (UIC) and thyroid function data, cord blood thyroid function studies, infant UIC, breast milk iodine concentrations, and infant neurocognitive data in a majority of the treatment group; this was a heroic feat. The major limitation of the study is the fact that it was not rigorously controlled. Apparently this was not by choice. The authors note that “the Ethics Committee . . . did not authorize the inclusion of a control group without treatment.” The authors selected a group of 61 untreated women to serve as controls. Because they were enrolled in the eighth month of pregnancy, thyroid function and urinary iodine measurements were not obtained in these women before the third trimester. Another 31 untreated women who experienced miscarriage at wk 8–12 were recruited to provide only UIC. Although there was no difference between treated and untreated groups in infant birth weights, Apgar scores, maternal age, frequency of prematurity, frequency and duration of breastfeeding, or parental education, neurodevelopment is an extremely complex process, and there are many potential confounders that could have contributed to the apparent difference in infant development between the study groups. Was the decision of the Ethics Committee appropriate? It would clearly be unethical to withhold iodine supplementation from pregnant women known to be severely iodine deficient. A blinded, placebo-controlled clinical trial begun in the 1960s in Papua, New Guinea, demonstrated that preconception supplementation of severely iodine-deficient women (median UIC 20 g/liter) with iodinated oil eliminated the risk for cretinism and improved offspring cognitive function and survival (3). These findings have subsequently been replicated in many regions of the world (4). A meta-analysis of Chinese studies suggests that iodine supplementation in severely iodinedeficient regions may increase the average child IQ by 12.5 points (5). The women in the Velasco study, however, were moderately but not severely iodine deficient at baseline. Although sample sizes were small, in the two untreated control groups, the median UIC were 69 and 88 g/liter—both below the optimal range of 150–249 g/liter as defined by the World Health Organization (6), and similar to the UIC of 84 g/liter previously reported for third-trimester pregnant women from Andalusia (7). What is known about the effects of iodine supplementation in pregnant women with this moderate degree of iodine deficiency? Seven previous controlled trials of iodine supplementation in moderately iodine-deficient pregnant European women have been published, although doses and timing of iodine supplementation varied, and only one previous trial examined effects on offspring development.

Investigation of intelligence quotient and psychomotor development in schoolchildren in areas with different degrees of iodine deficiency.

This investigation aims to observe the intelligence and psychomotor development of the schoolchildren in iodine deficiency (ID) areas after the adoption of Universal Salt Iodization (USI), and evaluate the effect of the adoption of USI on their intelligence and psychomotor development. 564 schoolchildren (306 males and 258 females, age range from 8 to 13 yrs) from areas with severe, moderate, and mild ID were investigated. Intelligence quotient (IQ) was measured by Combined Raven's test, second edition. Psychomotor development was examined by Jinyi Psychomotor Test Battery (JPB). We found that the IQ scores of all subjects in the severe and moderate ID areas were 102 +/- 15.6 and 99.5 +/-16.6 respectively, lower than those in the mild ID areas (108 +/- 12.4, p < 0.01). The IQ scores correlated negatively with age (partial r = -0.17; beta = -1.95; p < 0.0001). The total T scores of JPB of all subjects in the severe and moderate ID areas were 316 +/- 42.3 and 330 +/- 47.7 respectively, lower than those in the mild ID areas (342 +/- 48.1, p < 0.05). The total T scores of JPB correlated negatively with age (partial r = -0.15; beta = -4.94; p = 0.0006). We may conclude that after the adoption of USI in the ID areas investigated, USI has probably made a contribution to the partial recovery of intelligence and psychomotor development injured by ID in schoolchildren, and should be strengthened.

Iodine deficiency in school going children of Pondicherry

To assess the status of iodine deficiency in Pondicherry by finding out the urinary excretion of iodine and the prevalence of goiter among school children. 315 children between the age group of 9-13 yr from 30 schools in Pondicherry were examined for the presence of goiter and their urine samples were subjected to biochemical analysis to find out the urinary iodine levels (UIE). The percentage of children who had inadequate iodine intake and showed urinary iodine level of less than 100 mcg/ L was 44.4%. Amongst them, 14.3% had a greater degree of iodine deficiency with less than 50 mcg/L of iodine in urine. The prevalence of goiter was 15.24%. The prevalence of goiter is high. The iodine intake is quite low as exhibited by the UIE levels of < 100mcg/L in the children in Pondicherry, which might have had an unseen impact on the intelligence and school performance of these children.