World Status of Monitoring of Iodine Deficiency Disorders Control Programs

Abstract

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.

Iodine and iron status of pregnant women in Lubumbashi, Democratic Republic of Congo

“…A few countries have shown similar findings in pregnant women and the general population, as in Switzerland, the USA and Bulgaria, or Iran and China (16,35,36) . It should be noted that most of these countries with concordant results between pregnant women and the general population adopted salt iodization programmes a long time ago (Switzerland in 1922, USA in 1924, Bulgaria in 1958) (37) . In a recent literature review on iodine status which included surveys that took into account -as well as pregnant women and school-aged children -also pregnant women v. non-pregnant women, Wong et al came to the conclusion that the iodine status of pregnant women has to be addressed by considering pregnant women separately (38) .…”

Assessment of umbilical cord TSH in term Neonates in Manipur

“…Iodine deficiency remains the most common treatable cause of mental retardation Worldwide. Associated nutritional deficiencies in selenium and iron may have an effect on neurologic development and thyroidal response to iodine therapy 14 . Many countries have initiated salt iodination [14][15][16][17] .…”

Iodine nutritional status in Brazil: a meta-analysis of all studies performed in the country pinpoints to an insufficient evaluation and heterogeneity

“…Research questions (1) What is the overall prevalence of IDD in Brazil? ; (2) What is the prevalence of IDD in different areas and population groups?…”

“…odine is an essential micronutrient for the synthesis of thyroid hormones (TH), which are important for homeostasis and neurodevelopment (1)(2)(3)(4)(5). The World Health Organization (WHO) recomends daily iodine intake of 50 µg for newborns, 90 µg for children between 13 months and 6 years, 120 µg for children (7-12 years), 150 µg for adults (after 12 years) and 250 µg for pregnant and lactating women (6)(7).…”