International Council For Control Of Iodine Deficiency Disorders Research Articles

Dynamic monitoring of iodine sufficiency in Belarus: results and problems

The strategy for elimination of iodine deficiency in the population was developed and implemented in the Republic of Belarus. It is based on acceptance of recommendations that iodized salt is a unique source of iodine support. Currently, adequate iodine consumption is achieved. The prevalence of thyroid gland diseases caused by iodine deficiency was significantly decreased. In 2013, the International Council for Control of Iodine Deficiency Disorders (ICCIDD), a global non-profit non-governmental organization established to eliminate iodine deficiency and its negative consequences, published the results of iodine status assessment in the world. According to these data, the Republic of Belarus provides adequate iodine intake. In 2016, Iodine Global Network published maps characterizing iodine supply for the two main categories — school-age children and pregnant females. These data have confirmed that the Republic of Belarus refers to countries with sufficient iodine consumption according to the results of subnational studies. Despite the achieved successes, new issues are raised: quality of iodine sufficiency monitoring, risks of excessive salt intake, and need for new approaches to diagnosing thyroid pathology due to iodine deficiency.

Iodine nutritional status and awareness of iodine deficiency among adults, including pregnant women, in Tuguegarao, Philippines

Objectives Iodine deficiency causes multiple health problems. Previously we reported that 96% of high school students in Tuguegarao, Philippines had adequate iodine levels. However, iodine deficiency-associated problems remain among adults in the Philippines. Therefore, we evaluated iodine nutritional status and goiter prevalence among adults, including pregnant women, in Tuguegarao, Philippines. Methods A total of 245 adults, including 31 pregnant women, provided samples for urinary iodine analysis, and all pregnant women completed a questionnaire about iodine deficiency. Results The median urinary iodine level was 164.0 ± 138.4 g/L; 38.4% of the participants were iodine deficient, according to the International Council for Control of Iodine Deficiency Disorders (ICCIDD) criteria. No severe iodine deficiency was observed. Among the 31 pregnant women, 24 (77.5%) fell into the iodine deficient category defined by a stricter World Health Organization (WHO) guideline, in which iodine deficiency is considered when urinary iodine levels are below 150 g/L. Almost half (42%) of the pregnant women were unaware of the harmful effects of iodine deficiency on the human body and their fetus. Conclusions Although iodine nutritional status in the Philippines has improved, iodine deficiency still exists among adults, especially among pregnant women. Therefore, our study strongly suggests that a better strategy should be established to monitor iodine nutritional status among adults continually, and to focus on populations susceptible to iodine deficiency, including pregnant women and women of reproductive age, to achieve the total elimination of iodine deficiency.

A reliable and accurate portable device for rapid quantitative estimation of iodine content in different types of edible salt.

Continuous monitoring of salt iodization to ensure the success of the Universal Salt Iodization (USI) program can be significantly strengthened by the use of a simple, safe, and rapid method of salt iodine estimation. This study assessed the validity of a new portable device, iCheck Iodine developed by the BioAnalyt GmbH to estimate the iodine content in salt. Validation of the device was conducted in the laboratory of the South Asia regional office of the International Council for Control of Iodine Deficiency Disorders (ICCIDD). The validity of the device was assessed using device specific indicators, comparison of iCheck Iodine device with the iodometric titration, and comparison between iodine estimation using 1 g and 10 g salt by iCheck Iodine using 116 salt samples procured from various small-, medium-, and large-scale salt processors across India. The intra- and interassay imprecision for 10 parts per million (ppm), 30 ppm, and 50 ppm concentrations of iodized salt were 2.8%, 6.1%, and 3.1%, and 2.4%, 2.2%, and 2.1%, respectively. Interoperator imprecision was 6.2%, 6.3%, and 4.6% for the salt with iodine concentrations of 10 ppm, 30 ppm, and 50 ppm respectively. The correlation coefficient between measurements by the two methods was 0.934 and the correlation coefficient between measurements using 1 g of iodized salt and 10 g of iodized salt by the iCheck Iodine device was 0.983. The iCheck Iodine device is reliable and provides a valid method for the quantitative estimation of the iodine content of iodized salt fortified with potassium iodate in the field setting and in different types of salt.

The development of a global program for the elimination of brain damage due to iodine deficiency.

Iodine deficiency is the most common preventable cause of brain damage with more than 2 billion people from 130 countries at risk. The global problem of iodine deficiency has been redefined by a readily transmitted population concept, with an easy acronym - the concept of the iodine deficiency disorders (IDD) - referring to all the effects of iodine deficiency in a population, that can be totally prevented by correction of iodine deficiency with special emphasis on brain damage and not just to goitre and cretinism (1983). This was followed by the creation of the International Council for Control of Iodine Deficiency Disorders (ICCIDD) supported by WHO and UNICEF with 700 multidisciplinary professionals from more than 100 countries, committed to providing technical assistance to national programs for the elimination of IDD (1986). The WHO policy of Universal Salt Iodization (USI) has been widely adopted which requires iodization of all food for human and animal consumption by the use of iodized salt (25-40 mg I/kilo). Simple practical methods for monitoring - by the measurement of salt iodine and urine iodine were developed and promoted on a large scale with the technical assistance of the ICCIDD.

Hypothyroxinemia: a subclinical condition affecting neurodevelopment

Hypothyroxinemia with low levels of circulating free thyroxine and normal levels of thyrotropin, which is usually caused by iodine deficiency, may affect pregnant women even in apparently iodine-sufficient areas, and it is debated whether it increases the risk of neurodevelopmental abnormalities in children born to them. Epidemiological observations indeed indicate that this is the case. Animal models show abnormal brain cortical cytoarchitecture in pups born to mildly hypothyroxinemic dams. In regions where the availability and use of iodized salt is inadequate (where <90% of households use iodized salt), the WHO and the International Council for Control of Iodine Deficiency Disorders (ICCIDD) recommend iodine supplementation so that the total iodine intake is 250 µg/day to prevent iodine deficiency during gestation and lactation.

Urinary Iodine Concentrations Should Be Monitored to Diagnose Some Thyroid Gland Diseases in Heart Transplant Recipients

Background According to the World Health Organization, iodine excreted in urine is a measure of its supply. According to the International Council for Control of Iodine Deficiency Disorders (ICCIDD), the urinary iodine (UI) should be >100 μg I per 1 liter of urine. Severe deficiency (SID) is diagnosed when UI is <50 μg/L and a moderate deficiency (MID) when UI is <100 μg/L. Materials and Methods UI analysis among 32 heart transplant recipients (26 men and 6 women); of overall mean age of 50.4 ± 12.6 years was performed using the modified Program Against Micronutrient Malnutrition method, a spectrophotometric measurement based on the Sandell-Kolthoff reaction. Results were compared with those of thyroid stimulating hormone (TSH; μIU/mL), of free tri-iodothyronine (FT3; pg/mL), and thyroxine (FT4; ng/dL). Results The average UI among the whole group was 126.4 ± 109.6 μg/L. SID occurred in 12 patients (37.5%) and MID in 4 (12.5%); namely, mean UI of 17.0 ± 9.6 and 79.5 ± 5.6, respectively. In the other 16 patients (50%), the average UI was high, namely, 220.1 ± 72.1 IU/mL. TSH, FT3, and FT4 in the whole group were within normal ranges. However, FT4 values significantly differed when SID and MID patients were compared with those displaying the recommended UI: 0.8 ± 0.2 and 0.9 ± 0.1 versus 1.1 ± 0.2 respectively ( P < .05). We noted decreased values of TSH in 5 patients (15.6%) and of FT3 or FT4 in 6 subjects (18.8%). Conclusion There exists significant iodine deficiency among heart transplant recipients. Measurements of urinary iodine together with thyroid gland hormones may be essential to prevent thyroid gland disturbances in these patients.

Epidemiology and Impact of Iodine Deficiency in Pediatrics

Introduction Iodine is a micronutrient present in the human body in minute amounts (15-20 mg), almost exclusively in the thyroid gland. Iodine is an essential component of the thyroid hormones, thyroxine (T4) and triiodothyronine (T3), comprising 65 and 59 percent of their respective weights. Thyroid hormones, and therefore iodine, regulate many key biochemical reactions, especially protein synthesis and enzymatic activity. They also play a determining role in the process of early growth and development of most organs, especially that of the brain, which occurs in humans during the fetal and first two to three years of postnatal life. Consequently, iodine deficiency, if severe enough to affect thyroid hormone synthesis during this critical period, will result in hypothyroidism and brain damage. The clinical consequence will be irreversible mental retardation (1). The dietary intake of iodine recommended by the World Health Organization (WHO), the United Nation Children’s Fund (UNICEF) and the International Council for Control of Iodine Deficiency Disorders (ICCIDD) (2), are 90 μg per day from 0 to 59 months, 120 μg/d from 6 to 12 years, 150 μg/d for adolescents and non pregnant adults and 200μg/d during pregnancy and lactation (2).

Iodine induced thyroid disease.

Iodine is an essential requirement for thyroid hormone (TH) synthesis. The recommended daily iodine intake is variable, depending on the age of the subject; it is 40 µg/d during the neonatal period and 150 µg/d in the adult. The iodine requirement increases to approx 200 µg/d during pregnancy. Severe iodine deficiency, leading to various degrees of cretinism, is the major cause of mental and physical retardation in many developing countries, and its eradication is currently addressed by the International Council for Control of Iodine Deficiency Disorders (ICCIDD), United Nations International Children’s Education Fund (UNICEF), and World Health Organization (WHO). Mild to moderate iodine deficiency, ranging from 40–80 µg iodine daily, also is prevalent, including in many areas of continental Western Europe. In the United States, the average iodine intake in the 1988–1994 population was approx 150 µg/d, a decrease of more than 50% relative to 1971–1974 (1). A low iodine intake (<50 µg/d) was found in 11.7% of the population. Although the findings are not indicative of iodine deficiency in the overall population of the United States, the observed downward trend in iodine intake requires further close monitoring of iodine intake.

World status of monitoring iodine deficiency disorders control programs.

Monitoring and evaluation are the last phases of a national iodine deficiency disorders (IDD) control program but among the most important. This paper summarizes the latest recommendations by the World Health Organization (WHO), the United Nations Children's Fund (UNICEF), and the International Council for Control of Iodine Deficiency Disorders (ICCIDD) about indicators and their normative values for monitoring the progress of IDD elimination and illustrates the successful monitoring programs in Switzerland and in China. Salt is the usual vehicle for iodine supplementation and quality control for iodine content can be assessed quantitatively by titration and qualitatively by simple test kits that can be used in the field. The most useful indicator of iodine nutrition is the median urinary iodine concentration. Thyroid size, especially by ultrasound, and neonatal thyrotropin (TSH) are also valuable. In Switzerland, access to iodized salt on a voluntary basis started in 1922. The initial level of iodization, 1.9-3.75 ppm iodine as potassium iodide (KI), was slowly increased to 15 ppm, and recently to 20 ppm, after careful epidemiologic and biologic monitoring. Elimination of IDD has been highly successful. The program costs US dollars 0.07 per year per person. In China, a national program of iodized salt (10-30 ppm) started in 1960 under the authority of the central government and rapidly expanded. National monitoring surveys have taken place every 2 years since 1993. Median urinary iodine, initially low, increased to 165 microg/L in 1995 and to 306 microg/L in 1999, prompting a decrease in the amount of iodine added to salt. The total goiter rate decreased to 20.4% in 1995 and to 8.8% in 1999. IDD can presently be considered as eliminated in China. Review of monitoring in the 128 other major countries affected by IDD shows extremely variable achievements, with evidence of IDD elimination in at least 18 additional countries. Some countries that were severely iodine deficient in the past are now exposed to iodine excess and risk its effects. Sustainable elimination of IDD is within reach and would constitute an unprecedented global success story in the field of noncommunicable diseases, but continuing vigorous action is required to attain this goal.

Correlation between age, body size and thyroid volume in an endemic area.

Ultrasound is a safe, non-invasive technique that provides a more precise and objective method of determining thyroid volume than inspection and palpation, particularly in areas of mild endemicity, and generally whenever goiters are small. Thyroid volume is also correlated with age, weight, height and body surface area (BSA) in non-iodine-deficient areas. Different authors prefer different parameters to assess thyroid gland volumes. In this study, thyroid volumes were determined using ultrasound in 605 school children aged 6-11 yr who had been living for at least 5 years in Antalya. The correlation between age, BSA, height, weight, BMI and thyroid volume was sought in this mild to moderate iodine-deficient area. Somatic development of our children was in the normal range. Thyroid volume was significantly correlated with age (r=0.41, p<0.001), height (r=0.33, p<0.001), weight (r=0.30, p<0.001), BSA (r=0.33, p<0.001), and BMI (r=0.13, p<0.001). The most significant correlation was found to be with age. The application of the International Council for Control of Iodine Deficiency Disorders (ICCIDD) and the World Health Organization (WHO) thyroid volume references to our subjects resulted in prevalence estimates of enlarged thyroid of 31% based on BSA and of 34% based on age. In conclusion, when thyroid volumes are to be compared with reference values, assessment of thyroid volumes based on age is the most reliable method, in the event of normal somatic development.

Screening for congenital hypothyroidism used as an indicator of the degree of iodine deficiency and of its control.

Neonatal thyroid screening using serum thyrotropin (TSH) as the primary screening test detects not only permanent sporadic congenital hypothyroidism, whose incidence is about 1 per 4000 births, but also compensated or transient primary hypothyroidism, whose incidence can be as high as 1 in 10 neonates and whose main cause is iodine deficiency. Elevated serum TSH in the neonate indicates insufficient supply of thyroid hormones to the developing brain, and therefore, constitutes the only indicator that allows prediction of possible impairment of mental development at a population level, which is the main consequence of iodine deficiency. Therefore, the World Health Organization (WHO), United Nations International Children's Emergency Fund (UNICEF), and the International Council for Control of Iodine Deficiency Disorders (ICCIDD) included neonatal TSH as one of the indicators for assessing iodine deficiency disorders (IDD) and their control. In the absence of iodine deficiency, the frequency of neonatal TSH above 5 mU/L whole blood (or 10 mU/L serum) is less than 3%. A frequency of 3%-19.9% indicates mild IDD. Frequencies of 20%-39.9% and above 40% indicate moderate and severe IDD, respectively. Neonates exhibit elevated serum TSH more frequently than adults for a similar degree of iodine deficiency. Consequently, they appear hypersensitive to the effects of iodine deficiency. This characteristic is explained by a particularly low iodine content of the thyroid of neonates and, consequently, by an accelerated turnover rate of their intrathyroidal iodine reserves. This turnover rate is 1% in adults. It is 17% in the neonate in conditions of iodine repletion, but is as high as 62% and 125% in conditions of moderate and severe iodine deficiency, respectively. Such an accelerated turnover rate requires thyroid hyperstimulation by TSH that is morphologically evidenced even in moderately iodine deficient neonates. Neonatal screening using primary TSH is implemented in most countries with mild IDD where it detects the cases of sporadic, permanent congenital hypothyroidism and where it is also used as a monitoring tool for IDD evaluation and control. However, the implementation of such programs in countries affected by moderate or severe IDD is still insufficient because of lack of resources of the countries. This should be considered in the framework of the external support often provided to these countries for the implementation of programs of universal salt iodization. Monitoring of these programs in order to achieve the goal of sustainable elimination of IDD now constitutes an absolute priority.

Communication and health — health as an ecosystem

The importance of communication in public health is described with reference to recent experiences in Australia where good progress has been made with certain major public health problems. There has been a 30% fall in road accident deaths and a 40% fall in deaths from coronary heart disease, and a smoke free environment has been established in public places and in the work place. These successes depended on effective communication based on appropriate data. Evaluation data have also been used to keep the public informed and to reinforce the message. The cooperation of the media has been most important in stimulating a new awareness of health and the opportunities for self help and community initiatives. In central Australia, new initiatives involving the Central Australian Aboriginal Congress have led to an improvement in the health of Aborigines, the training of Aborigines as health workers and the development of a Centre for Appropriate Technology at the Alice Springs College of Technical and Further Education. At the international level, Australia sponsored a World Health Assembly resolution in 1986 calling for the elimination of iodine deficiency disorders. With the support of the Australian International Development Assistance Bureau and the United Nations Children's Fund (UNICEF), an international expert group of scientists and public health professionals, the International Council for Control of Iodine Deficiency Disorders (ICCIDD), based in Adelaide, has been able to work with the World Health Organization (WHO) and UNICEF in the development of an international public health programme aimed at eliminating iodine deficiency disorders by the year 2000. The ICCIDD is a new model for communication and action in international health which is now being advocated for other areas.