Volume 11 Number 3, August 1995

IN THIS ISSUE

Thyromobil Project Standardized Iodine Deficiency Evaluation in Europe.

F. Delange, J. Podoba, F. Vertongen, W.Ott, ICCIDD Regional Office for Europe, Brussels, Belgium.

The ThyroMobil project has been developed and conducted by a core group of 12 European thyroidologists from the 12 countries involved in the project, Germany, Austria, Poland, Romania, the Czech Republic, the Slovak Republic, Hungary, Italy, France, Belgium, Luxembourg, and The Netherlands. Its main objectives have been to update information on the iodine supply in Europe, to increase awareness of IDD in the affected countries, and to stimulate the prevention and treatment of IDD in the continent. The project, with Professor F. Delange, Executive Director of ICCIDD and Regional Coordinator for Europe, as the principal investigator, has been carried out under the auspices of ICCIDD and sponsored by the E. Merck Company, Darmstadt, Germany (Project Manager: Dr. Ott). The European offices of UNICEF and WHO supported the public interest objectives of the project.

A mobile unit ("ThyroMobil" van) (Figure 1) equipped with an ultrasonograph supplied by Siemens (Figure 2) visited at least two sites in each of the countries under investigation. Some had been studied in the past and were selected to recognize possible changes in the iodine supply, while others had not been previously investigated.

Following the recommendations of ICCIDD, WHO, and UNICEF, the assessment of iodine supply included the determination of thyroid volume by ultrasonography and of the urinary concentration of iodine in groups of at least 100 schoolchildren of both sexes aged 6-17 years in each site. Iodine deficiency was considered to be present if more than 5% of subjects had a thyroid volume above the 97th percentile for age and/or if the median urinary iodine concentration was below 10 mg/dl. To ensure technical uniformity, all ultrasonographies were performed by the same experienced physician (Dr. Jan Podoba, University of Bratislava, Slovak Republic) and all urine samples were analyzed in the same laboratory (Department of Clinical Chemistry, University Hospital Saint-Pierre, Brussels, Belgium, Professor F. Vertongen and Mrs. D. Gnat). In addition to data on thyroid size and urinary iodine, we obtained information on the use of iodized salt, sea fish, and milk. Any thyroid abnormality detected by ultrasonography was communicated to local practitioners for prompt action. Field investigations began in 1994 and were completed by March 1995. A total of 7,601 schoolchildren aged 6-17 years from 57 different sites in the twelve countries were examined, and statistical analyses was performed in Bratislava by Mr. Srbeky and Dr. Podoba, in close coordination with the principal investigator. Urinary iodine concentrations was determined in 5,728 samples.

The results indicate marked regional patterns for both variables: the median urinary iodine values were normal in almost all sites investigated in the Netherlands, the Slovak Republic, Germany, Austria and France, borderline in Luxembourg and the Czech Republic, low (with a few exceptions) in Italy, Hungary, Belgium, and Romania, and very low in the three sites investigated in Poland, which were situated in the endemic goiter areas of the country.

There was a significant inverse relationship between the median urinary iodine and the frequency of goiter (defined as a thyroid volume above the 97th percentile according to the criteria originally proposed by WHO, UNICEF, and ICCIDD). However, by these criteria, the frequency of goiter was also high even in communities with entirely normal urinary iodine concentrations. Therefore, the criteria for a normal thyroid volume as a function of age and sex in children and, from them the definition of goiter, have been re-evaluated from the data collected in children living in iodine replete areas in Europe. These new criteria will be officially communicated to the international organizations.

While the ThyroMobil van was in each country, a press conference was organized, usually in the capital. The conference included reports on the status of iodine nutrition in each country by the national representative of the ThyroMobil project, by the principal investigator and, as much as possible, by representatives of the national Ministries of Health and national UNICEF committees. Extensive coverage by TV, radio, and the press were arranged in all countries.

The following conclusions can be drawn from the ThyroMobil project:

Ghana Assesses its IDD

A workshop on IDD in Ghana was held in Accra in July 1994 to discuss findings from a three-year survey carried out by the University of Ghana and the Ministry of Health, with major funding support from the International Development Research Center of Canada. The proceedings have been edited by Dr. E. Asibey-Berko and Dr. R. Orraca-Tetteh of the Department of Nutrition and Food Science, University of Ghana. Here we report some highlights.

IDD PREVALENCE

The survey included four towns or villages from each of 30 districts, selected randomly from the country's ten regions. A total of 1,000 people, 500 children aged 10-19 years and 500 women, aged 15-45, were examined or interviewed in each district. Data included neck palpation for thyroid size, a casual urine sample from 10% of the subjects for iodine concentration and a questionnaire about drinking water, food habits, and knowledge about goiter.

Data on goiter prevalence and urinary iodine concentration by region and district are presented in Table 1. The most severe iodine deficiency was found in the far north, upper east, and upper west regions, with 56% goiter and urinary iodines in the 1-3 mg/dl range. Overall, iodine deficiency was severe in two of the 27 districts and moderate in six. Of the remaining 19, many had mild iodine deficiency as shown by a urinary iodine level between 5 and 10 mg/dl. The correlation between goiter prevalence and distance from the sea was very strong.

SALT CONSUMPTION HABITS

The survey assessed salt consumption habits by questionnaire in 45 households per district. Additionally, about 40 households per district were assessed by three-day weighed salt intake. For these a "total household adult equivalent" was calculated by assigning weighted factors related to age (e.g., age six months to four years, 0.5; age five to nine, 0.75; greater than ten years, 1).

Household salt is stored mostly in open containers. Most respondents used coarse sea salt of coastal origin, and reserved granulated salt only for further addition after cooking. The most common packaging material was polyethylene (79%). The vast majority of respondents (97.8%) did not know about iodized salt. From the three-day weighed salt intake study, the average daily salt intake for adults was 10.46 grams in urban areas and 11.18 in the rural. The range for the areas examined was 5-17 grams. These levels agree with previous data showing mean salt intakes of 11.5 grams, derived from direct analysis of foods eaten by university students. The study notes that some iodine loss may be anticipated with cooking methods; e.g., when salt has been added to water for boiling roots and tubers, the water is usually discarded.

The study also analyzed iodine content in a total of 234 samples from salt traders in 13 districts. The mean iodine content was 7.87 ± 4.64 ppm. Twelve of these sources were sea salt and demonstrate the very low iodine content found in natural sea salt. Rock salt from Daboya was an exception, and had 16 ppm.

KNOWLEDGE AND ATTITUDES ABOUT IDD

As part of the survey, 1200 of the study subjects were selected at random for interviews. The results show that 98% had heard of or had seen goiter, and most ethnic groups had local names for it, including Kueshikpo (Ga), Kompo (Akan), Semkpo (Adangme), Bapolo (Kasem), and Avo (Ewe). As to cause, 66% had no opinion, 11% attributed it to "natural causes," 7% to hereditary, 2% to iodine, 2% to supernatural forces, and 12% to a combination of these factors. Some common perceptions of cause were: (1) excessive accumulation of mucus or bubble-like fluids in the body; (2) hernia; (3) kookoo (a generic name for all manner of diseases including hemorrhoids); (4) drinking unclean water or eating unclean foods; (5) spitting into the fire; (6) over-consumption of salt; (7) being talkative; and (8) crying excessively during childhood.

Most respondents (54%) did not think goiter was contagious or that goitrous subjects needed isolation; 39% were not sure, and 7% thought goiter was either infectious or a manifestation of evil. For treatment, some of the options included the hospital (29%), the traditional healer (7%), and self-medication with pharmaceutical products or herbs (4%). For 5% the disorder was thought to "come from the blood" and, therefore, could not be treated. For those self-medicating, treatments included alum solution, tincture of iodine, and plants and roots. In the questionnaire, 40% thought goiter was hereditary, 16% said it was incurable and 19% thought only females have goiter.

The investigators note the need for including the beneficiaries in organizing the program. Many rural people do not have access to mass media and are not literate, thus mass media education has not been particularly successful. The affected communities should be involved in the planning and implementation of a program, through village committees and community education exercises.

SALT PRODUCTION AND MARKETING

The investigators tried to identify all salt producers in the country, and reported results with the 88 that they actually reached. Ghanian salt comes chiefly from the sea and is produced by solar evaporation. Salt is produced in three principal ways: (1) the Ada salt process in which seawater flowing into coastal lagoons evaporates in the sun during the dry season, leaving large crystals of salt that are quite impure; (2) stove salt process - brine is collected in containers and then heated, by steam pipes, oil burners, or firewood; (3) pond salt process - most modern units use this technique which consist of solar evaporation from salt bands built on coastal lagoon flats. About half of the production is in modern factories and the other half by simple artisanal methods. The book presents detailed maps showing sites of origin along the sea coast and their marketing distribution. Most of the artisanal units are east of Accra, while the factories are west. The combined output from 12 major production sites is estimated at 191,378 metric tons per year. About half of the salt producers belong to one of four identified salt producers' associations; a major benefit from belonging is the opportunity to obtain salt producer's welfare. Large factory producers do not belong to these associations. Recently a national salt production association has been formed. In the questionnaire, less than 10% of respondents were aware of iodized salt but 93% were willing to participate in any pilot iodization project.

SALT MARKETING

The study surveyed salt markets and traders in the country. While 93% of the production is sold within the country, some also goes to other countries, particularly Niger, Togo, and Burkina Faso. About 30% of the domestic salt is consumed in the Accra region. The preferred type of salt is "sea white" or "sea grey," which together comprise 93% of the market. Less than 2% is rock salt. The report charts the salt traders and their source of salt by region. However, 45% of the traders did not know where their salt came from. About half of the salt traders buy from retailers, indicating that yet another layer exists between producer and consumer. The frequency of salt purchases is affected by limited working capital and limited salt demand. Eighty-one percent of the salt traders sell small amounts. Most sales take place in the market place but some also occur at the trader's residence. Only 5% of the traders interviewed were members of any trade association, the rest operating independently. Ninety-six percent of the salt traders had no knowledge of iodized salt, and the rest did not know its purpose.

Some salt is imported, almost all from the United Kingdom, the rest from Germany and China. The amount imported fluctuates widely, for example, 50 metric tons in 1992, but only 2 metric tons in 1991.

Ghana exports salt, in amounts ranging from 31,000 to 75,000 metric tons from 1987 to 1992. The major destinations were Niger, Burkina Faso, Togo, Nigeria, Mali, the Ivory Coast, Benin, and the Congo. The exports trade is not handled directly by salt producers but by others.

Of the traders interviewed, 96% were females. Most traders deal in small quantities of 3-30 kilograms, purchased every week, two weeks, or month. The study notes that packaging of iodized salt should be kept to small sizes since the present marketing situation is not likely to change.

IODIZED OIL ADMINISTRATION

The survey showed that iodine deficiency was very severe in the upper east region. In 1991, UNICEF donated iodized oil capsules that were distributed in the field by a special team formed in the Nutrition Division headquarters. Coverage was small, the operation was expensive and the use of special task teams could not be sustained because it was not a normal routine of the Ministry of Health. For these reasons, an alternate system was adopted in 1993 to ensure that iodized oil administration was integrated into existing Ministry of Health programs. In this project iodized oil capsules were distributed to district health medical teams, who were encouraged to deliver capsules at outpatient departments, outreach services, child welfare clinics, antenatal clinics, school health clinics, and home visits. The objective was to give a full dose of iodized oil to all individuals, aged 1-45 years. Problems in this program included difficulty in recording capsule administration, an uneven supply of iodized oil capsules and demand out-stripping supply. Follow-up of this program is needed.

FURTHER PLANS

The conference reported on progress towards salt iodization. So far, salt producers have been sensitized to the iodization program, the needs assessment for production and iodization equipment has been completed, and orders placed. The Standards Board has produced detailed specifications and proposed an iodine content of 100 ppm at the factory and 50 ppm at retail. Legislation for iodization of all salt for human and animal consumption is being prepared. An association of salt producers has been formed in the central region and a similar national body is being set up. Samples of salt are being collected and analyzed for impurities to determine the need for technical support to improve salt quality. Future steps proposed include licensing of all salt producers, an intensive education campaign and incentives for motivating producers, including soft loans for equipment purchase, technical assistance, free supply of iodine, and training. A quality control program is being prepared and a marketing study for exporting salt is underway. A national micronutrient working group has been formed to draft a national plan of action for preventing and controlling specific micronutrient deficiencies. Key strategies include intersectoral collaboration and coordination, advocacy and social mobilization, social marketing and communication, human resource development and capacity building, development of an effective information system, research and strategic intervention. The latter includes distribution of iodized oil in severe areas and has already been started in the upper east region. The long-term objective is salt iodization. Operational research has been proposed, particularly on food consumption habits, factors affecting availability of nutrients, indigenous methods of food processing and preparation, and nutrition education.

FINAL RECOMMENDATIONS

Table 1: Goiter prevalence and urinary iodine levels, by region, in Ghana.

* Not yet available.

Iodine Deficiency in Poland

The Polish Council for Control of IDD held its Second Scientific Conference in Krakow, May 1993. Sponsors included WHO, UNICEF, ICCIDD, the International Atomic Energy Committee, the Ministry of Health and Social Welfare, the State Committee for Scientific Research, the Foundation for Polish Science, the Polish Society of Endocrinology, the National Atomic Agency and Jagiellonian University. The Advisory Committee included Professor M. Gembicki (ICCIDD Senior Advisor), Professor J. Nauman, Professor M. Rybakowa, and Professor Z. Szybinski. The Proceedings have been published in an English language version as volume 44, number 3 of the Polish Journal of Endocrinology, edited by Professor Szybinski, who has kindly forwarded a copy to the IDD Newsletter. The following information is abstracted from it.

Goiter has been recognized in Poland for many years. Of the two major recognized foci, one in the southeast is part of the Carpathian mountain endemia, which includes parts of Slovakia and Romania, and the other is the Sudeten endemia in Poland's extreme west. The Carpathian endemia has been known for years, and cretinism was frequently reported. The Sudeten endemia was recognized in Polish people moved from eastern areas after the Second World War.

Subsequent surveys found IDD in the central and northeastern areas of Poland as well. In the Krakow area iodized salt at a level of 5 ppm was begun in 1935, stopped by the Second World War, and started again in 1947. Prophylaxis in the range of 5-12 ppm continued until 1980, when it was interrupted throughout the country in association with economic crises. Addition of KI to salt was resumed again in 1986, as a voluntary measure without specific regional distribution. Scattered surveys from 1988 to 1990 showed an increased goiter prevalence in several regions and increased neonatal TSH's, indicating that IDD continued to be a significant problem. Because of these findings, the Polish Society of Endocrinology created the Polish Council for the Control of IDD in 1991. This body took as its first task the organization of a nationwide epidemiologic survey, for which funding was obtained from the Polish government.

The survey was organized through departments of endocrinology at medical schools in the country, with each of 10 centers covering two to seven districts. Figure 1 shows the areas covered by each of these centers. Data were also assessed according to geographical features of the country, as shown in Figure 2. Techniques for thyroid palpation, ultrasonography, and urinary iodines were standardized. In all a total of 19,330 children, ages 6-13, were examined, representing about 0.4% of the country's population of this age. These children attended 111 schools, selected at random, two to four schools in each district, depending on its geographical homogeneity. Each child was examined with neck palpation by one physician and with ultrasound by another. Urine samples were also collected, as well as a questionnaire about iodized salt consumption and personal data. Dr. Gutekunst of ICCIDD participated in training for ultrasonography and urinary iodine determinations.

SURVEY DATA

Comparison of ultrasound and palpation - The investigators carefully addressed the issue of ultrasonographic definition of thyroid enlargement and relating it to results by palpation. They began by taking as normal thyroid size, the volume by ultrasonography of children who were classified as WHO group 0 (no goiter) by palpation. From this they proposed means and upper limits of normal for age group 6- 13 as shown in Table 1. The authors note that these values are somewhat higher than those proposed by Gutekunst for iodine sufficient children (IDD Newsletter 6(4):30, Nov. 94). [Ed note: they are also above those published for iodine sufficient controls in Italy and in Belgium; for further ultrasound data, see article on IDD in Turkey by Kortoglu et al. in this issue of the IDD Newsletter).

The investigators encountered the common difficulty of palpation accuracy in small thyroids (0, IA, and IB in the former WHO classification or 0 and I by the new classification; see IDD Newsletter 10(4):39, Nov. 1994). They found that if they included IA, IB, II, and III as goiter, the goiter prevalence was 81.6% but if they included only IB, II, and III it was 29.5%. Using the criteria for goiter by ultrasound described above, their total prevalence was 25.9%. On this basis they decided to count only stage IB and above, by palpation, as goiter.

Table 2 summarizes information about goiter prevalence, by ultrasonography, and urinary iodine, distributed among the six geological zones shown in Figure 2. The report divided the data for goiter between children receiving iodine prophylaxis and those not receiving it, and divided data on urinary iodine between children with goiter and those without; in neither instance were differences between the two groups important. The presence of goiter was inversely correlated with urinary iodine levels. Significant variables in relation to urinary iodine concentration were geographical area, iodine prophylaxis, and residence (urban versus rural). Sex, height, body mass, and age were not related.

The report also summarizes the use of iodized salt, as reported by the children being surveyed. The overall figure was 22.5%, ranging from 11.2% in Szczecin to 43.4% in Katowice, with the lowest being in the seaside area. The currently available iodized salt in Poland, 20 mg KI/kg table salt as voluntary prophylaxis, is fairly ineffective. Only about 20% of the children use it and their urinary iodine concentrations were only about 10% higher than those of other children. The prevalence of goiter in the group using iodized salt was about 10% lower than in others, but iodine prophylaxis did not appear to have a significant effect on thyroid volume.

The report includes additional data and comments from the individual coordinating centers.

Krakow - This area had long been known to harbor endemic goiter. Iodized salt had been used, but was interrupted at the main salt mine in Wieliczka in 1980; this was the biggest producer of iodized salt in southern Poland and the area again became iodine-deficient. The prevalence of goiter in the survey was 38% of the population, 62% of children, and the urinary iodine excretion was lower than 50 mg/l. About 30% of the children consumed iodized salt at least some of the time.

Wroclaw - The highest prevalence of goiter was in the mountainous regions where it reached 47.9% in the children in the Sudeten endemia and 38% in upland villages. The consumption of iodized salt did not make any apparent difference in the goiter prevalence. The iodine concentration in urine ranged from 66.7 to 88.6 mg/l.

Lodz - The overall goiter prevalence was 32.7%. Palpable goiter was found in 47% of the rural population and 30% of the urban in one district. Two percent of the children had nodular goiter. The mean urinary iodine concentration was 64 mg/l.

Warsaw - On palpation 49% of the children had goiter, more in rural areas (54%) than in towns (42%). By ultrasonography using the Gutekunst criteria, thyroid volume was considered enlarged in 46% of the children. Only 12% reported using iodized salt. Urinary iodine levels were higher in those who used iodized salt (76 mg/l) than in those who did not (55 mg/l). Also, the mean urinary iodine was lower in goitrous children (54 mg/l) than in normals (61 mg/l).

Bialystok - Palpation revealed goiter in 39% of the children. By ultrasonography enlargement was estimated at 60%. Iodized salt was used by 26% of children in the city, 16% in the villages. There was no apparent difference between those using iodized salt and those not. Mean iodine concentration in the urine was higher in the goitrous (52.7 mg/l) than in the nongoitrous (42.3). There was no association between goiter and level of physical development.

Katowice - By palpation 18% of the examined children had goiter. Mean thyroid volumes were 3.85 (8-9 years), 4.54 (9-10), 6.02 (11-12), and 6.36 (13 years). These values are fairly close to those reported by Vitti et al. for iodine-sufficient Italian children. About half the children used iodized salt. The mean urinary iodine concentration was 70.6 mg/l. Thus this area is not as severe as others in Poland.

Lublin - The goiter prevalence was 29%, and mean urinary iodine levels were about 54 mg/l. About 23% of families used iodized salt.

Poznan - By palpation 28% of the children had goiter, but by ultrasound the figures were 37% in towns and 46% in rural children. Thirty-seven percent reported using iodized salt at home. The mean urinary iodine excretion was 96 mg/L (median 84) for urban children and 87 mg/L (median 64) for rural. The area is classified as mildly iodine-deficient.

Gdansk - Sixteen percent of the children had goiter, ranging from 9% to 23% among various towns. The urinary iodine concentration ranged from 90 to 123 mg/l. Only 13% consumed iodized salt.

Szczecin - The mean urinary iodine concentration was 76 mg/l, and the goiter prevalence was 12.9%. Only 11% of children consumed iodized salt.

SPECIAL STUDIES

In addition to survey data, the report includes other topics of interest. One study on the iodine concentration of drinking water and food specimens, using an X-ray fluorescent method with 241-am as exciting radiation source, found that over 70% of 83 samples of water from different outlets in southern Poland had an iodine concentration below 3 mg/dl. Several analyses of eggs and milk showed low iodine concentrations as well.

Another study examined 46 pregnant women in a moderately iodine-deficient area of the Krakow region. The mean newborn weight was 3338 grams, mean maternal thyroid size by ultrasonography the day after delivery 27.8 ± 15.2 ml, and mean urinary iodine levels were 35 ± 29 mg/L. Thyroid hormone values for mothers and newborns were normal; the women in this group did not use iodized salt. Mean values for maternal blood were T3 1.5 ng/ml, T4 11.6 mg/dl, TSH 2.3 mU/ml; values for umbilical cord blood were T3 0.59 ng/ml, T4 10.6 mg/dl, TSH 3.7.

CONCLUSIONS AND RECOMMENDATIONS

The report concludes that Poland has mild to moderate iodine deficiency. The highest prevalences were in the Sudeten, Carpathian, central and northeastern parts of the country, where 40-80% of the children had urinary iodine levels below 50 mg/l. The lowest goiter prevalences were in the northwestern part of the country where 60-90% of urinary iodine concentrations were above 50 mg/l and about 25% above 100. Only about 20% of the population uses iodized salt.

The Polish Council for Control of IDD made the following recommendations, based on the findings of this report.

Table 1. Proposed means and upper limits for thyroid size of normal Polish children.

Table 2. Goiter prevalence and urinary iodine, by geologic zones.

a Data for children reportedly receiving prophylaxis; figures differ little from those not on prophylaxis.

b Data for children with goiter; figures differ little from those without goiter.

Normal Thyroid Volume of Children in Turkey: Pilot Study in Kayseri Province

S. Kurtoglu, I. E. Covut, M. Kendirci, K. Uzum, A. C. Durak, A. Kiris, Departments of Pediatric Endocrinology and Radiology, Erciyes University Medical Faculty, Kayseri, Turkey.

The presence and prevalence of goiter are important indicators of iodine deficiency in a given geographical area. Thyroid size can be estimated by neck palpation, radioiodine scanning, or ultrasound. Palpation is fairly reliable when applied to adults and large thyroids, but an error rate of at least 20% is found for smaller thyroids. Palpation is even less reliable in children, especially newborns (1). Ultrasound is a precise, safe, reproducible and cost-effective method for assessing thyroid size and morphology, and has been recommended by many investigators (2-4). Under proper conditions the maximum deviation of measurement is approximately ± 8% (2). As expected, mean thyroid volumes vary among different geographical areas in association with the amount of iodine ingested by the population.

The present study reports thyroid sizes of children in Kayseri Province in central Turkey. We estimated the thyroid volumes of 340 boys and 340 girls, age 0-16, using real-time ultrasonography (Toshiba Sonolayer L, SAL 77A with 7.5 MHz probe), by measuring dimensions of each thyroid lobe and calculating total thyroid volume from the width x length x thickness x p/6 (5).

Table 1 shows results, expressed as the mean ± standard deviation. For comparison we give values of mean thyroid volumes from Belgium (6) and Italy (4) and upper limits as recommended by Gutekunst (1). Table 2 compares thyroid volumes of newborns in our study with those published from Germany (7,8) and Belgium (6).

The volumes in children in our study are higher than those reported from Brussels (6), and lower than the upper limits proposed by Gutekunst (1). Our values are fairly similar to those reported by Vitti, et al. (4) from their iodine-deficient area (median urinary iodine 72 mg/l) and higher than those from their control area (median urinary iodine 110 mg/l). Similarly, our values for newborns are higher than those in Belgium, but lower than reported from a markedly iodine-deficient area of Germany.

We find that ultrasound is a precise and practical means for assessing iodine nutrition in a population. Our results suggest that Kayseri has mild iodine deficiency. We plan to perform further investigations including urinary iodine excretion and to search for other goitrogenic factors. Depending on these studies, iodized salt administration may be necessary.

REFERENCES

Table 1. Mean values (± SD) of thyroid volume in ml, from neonate to 16 years in Kayseri, and comparison with two other studies. The last column gives upper limits of normal proposed in another study (1).

Table 2. Newborn mean thyroid volume of Kayseri compared with some published values.

IDD in Sikkim

Sikkim, lying in the eastern Himalayas, has previously been identified as harboring severe iodine deficiency. A group of concerned physicians at the Thyroid Center of the Government General Hospital in Namchi, South Sikkim, carried out a prevalence survey and additional studies two years ago and the results have been collated by Dr. T. Pulger, Dr. R. Sankar, Dr. B. M. Rai, and Dr. Bimal Rai. This report summarizes some of the principal findings.

Background - Sikkim is bounded by the Tibetan plateau in the north, Bhutan and the Chumbi Valley of Tibet in the east, Nepal in the west, and west Bengal in the south. The altitude ranges from 300 to 5500 meters. The overall population is about 316,000, of which 84% is rural. The three major ethnic groups are the Bhutia, Lepcha, and Nepali. The literacy rate is 34%.

Survey - Nearly 18,000 individuals from 3200 households were examined, by house-to-house survey. All available members of the household were examined. Forty-three percent were below the age of 15 and 85% below the age of 45. The thyroid examination was by palpation, using the older WHO system in which grade I is a visible goiter with the neck extended, grade II with the neck in normal position, and grade III a larger goiter recognizable from a distance. The overall goiter prevalence was 54%, ranging from 46 to 61% among the four districts. Sixty percent of females and 49% of males had goiter. The prevalence increased with age, from 11% in those four years old or younger to 69% in those over 60. Of the households examined, 96% had at least one resident with goiter.

The overall prevalence of cretinism was 3.5%, predominantly the neurological type, with only 1% recognized as myxedematous. The Chengthang area had the highest cretinism prevalence, 15%; its goiter prevalence was 75%. Of the 617 cretins observed, 228 were clustered in 99 families; 75 families had two cretins each, several had more and one family had 5 cretins. Three cretin couples were found; one couple had four normal children, another had one normal child, and the third had both normal and cretinous children. The goiter prevalence among cretins was 65%. The most prominent neurological feature in the cretins was deaf mutism (77%). Other prominent features were proximal spasticity, rigidity, and squint.

Detailed neurological examination in 119 cretins showed a mean height of 138 cm, mean head circumference 51.9 cm, 48% had goiter, 76% were deaf mutes. Testing of hearing acuity by audiometry in a subset of 38 cretins showed two to have normal hearing, mild to moderate loss in 9 and severe to profound loss in 22. All had severe mental retardation.

Testing of intellectual function in 90 schoolchildren from a severely iodine-deficient area, in which 91% had goiter, showed the following results: Bender-Gestalt test for visual motor reproduction, no impairment 31%, mild to moderate 29%, and severe 40%. The Binet Kamat test for mental ability, showed 45% to be average (85-115), 34% borderline (70-84), 19% mildly retarded (50-69), and 2% moderately retarded (35-49). Thus at least 21% of these schoolchildren were mentally retarded. Eighty-five percent of the children had a mental age two years less than their chronologic age. It should be remembered that more retarded children would not typically be in schools.

Urinary iodine levels were measured in two villages, Sadam, (goiter prevalence of 74%, cretinism 4.4%), and Maniram (26% goiter, no cretinism). The mean urinary iodine levels were respectively 4.13 and 6.31 mg/l, and in each instance the level in the nongoitrous population was about twice that in the goitrous. Serum levels for nongoitrous subjects were higher for T4 and lower for T3 and TSH, although all values were essentially within normal limits.

The report briefly notes the development of the Thyroid Center of the Government General Hospital in Namchi. Begun in 1989 by order of the Chief Minister, its purpose has been to meet training needs, to carry out fundamental research and to serve as the state's reference center for IDD. A task force has responsibility for IDD surveillance and the control program. Its facilities include a radioimmunoassay lab, an iodine monitoring lab, and a thyroid clinic. Its major activities have included the epidemiologic survey of the entire state, an information, education, and communication campaign, courses on iodine monitoring procedures, and hearing aid camps. The program has as its goal a goiter prevalence of less than 10% by 1995, an incidence of neonatal hypothyroidism of less than 1:1000 births, no new cretins, and a marked diminution in the prevalence of subcretins.

The IDD Newsletter is grateful to Dr. T. Pulgar, Chairman of the Thyroid Center, and Lt. Col. R. Sankar, Honorary Consultant and Medical Specialist, for making this report available to the Newsletter.

In Brief......

Jodbasedow (Iodine-Induced Thyrotoxicosis) - Hyperthyroidism can occur, particularly in older subjects with thyroid nodules, when a previously iodine-deficient area is provided with iodine. The usual trend over time is an increase in the incidence of hyperthyroidism in the population for one or two years, followed by a decrease in the overall incidence, to a level lower than existed before correction of iodine deficiency. ICCIDD has learned of some countries where Jodbasedow may have occurred during the last several years, associated with an increase in iodine supplementation. These reports are being investigated by ICCIDD, together with UNICEF and WHO, and also by individuals in countries. ICCIDD is also asking for comments from other countries where iodization has been implemented in the last five years; responses so far from several with successful iodization programs have failed to reveal significant Jodbasedow. A small research meeting was held in Brussels at the request of the European Community, the funding group for a study of IDD in Africa. The conferees reviewed reports of an increase in hyperthyroidism associated with large increases in iodine availability in areas that were previously severely iodine-deficient. A short report is being prepared. While Jodbasedow is a recognized complication of IDD and its correction, the benefits of iodization programs for iodine deficient countries far outweigh the disadvantage of Jodbasedow. Further attention is being given to optimal levels of iodine in salt. In general, many authorities recommend that such levels be adjusted to achieve a mean daily iodine intake of 150-200 mg. From this perspective, the amount of iodine to be added to salt can be calculated from knowledge of the baseline iodine intake from other dietary sources, the average amount of salt consumed daily, and losses of iodine from salt between the points of production and consumption. Since these factors vary among different countries and geographical regions, so will the optimal amount of iodine to be added to salt at production. Methods for treating the hyperthyroidism when it occurs, are usually quite successful and follow the approaches for therapy of hyperthyroidism from other causes. Readers with further information about Jodbasedow in different geographical regions are encouraged to correspond with Dr. Delange, ICCIDD Executive Director.

CIDDS Database - The OMNI project funded by USAID, has agreed to continue funding for this database (IDD Newsletter 11(1):2, Feb. 95). It has entries for each country, with information in the following categories: (1) assessment information, particularly goiter prevalence and laboratory data; (2) legislation on salt iodization; (3) identification of government of other authorities responsible for IDD control, and a description of the program; (4) current efforts at information, education, and communication; (5) a summary of the sources, production, iodization, costs, marketing, and transport of salt; (6) supplementation measures other than iodized salt; (7) monitoring, and (8) comments on impending developments, random notes from observers, and sources for further information. The fourth edition is planned for completion in late 1995, with a subsequent updating in mid-1996. Information in the database is available on diskette and is planned for distribution via the Internet, to all those with a reasonable professional interest. The Micronutrient Initiative is drafting plans for coordination of micronutrient databases and their dissemination, and ICCIDD is actively participating in this effort. Readers with up-to-date information on specific countries are urged to communicate with Dr. Dunn at ICCIDD, for inclusion of this information in the database update, and also for related items of interest suitable for the IDD Newsletter

"Salt Iodization for Correction of Iodine Deficiency" - This 126 page booklet is now ready for distribution. It appears under the logo of ICCIDD, UNICEF, WHO, and the Micronutrient Initiative. It provides a short, non-technical account of salt iodization and its use in eliminating iodine deficiency. Copies can be obtained through ICCIDD, the Nutrition Unit at WHO, or UNICEF.

Symposium on Iodine Deficiency, Diabetes, and Environment, Tahiti - This symposium is scheduled for June 18-19, 1996 as an official satellite of the Tenth International Congress of Endocrinology, San Francisco, USA, June 12-15, 1996. For further information, contact Dr. J. L. Boissin, Papeete, Tahiti, fax 689 45 20 31.

Teaching-aids at Low Cost (TALC) Set on IDD - This program, with the active collaboration of ICCIDD, has produced a new set of 24 IDD slides as teaching aids for trainers of community health care workers and other development personnel. They are accompanied by a text for the trainer. Further information about availability can be obtained from TALC, P. O. Box 49, St. Albans, Herts AL1 5TX, United Kingdom, FAX 44 (0) 1727 846852.

Second ALGEPA Award for Research on IDD - A.L.G.E.P.A. [Association pour la Lutte contre le Goitre Endemique et les Pathologies Associees (Association for the fight against endemic goiter and associated pathologies)], a non-profit organization, has set up an award of US $6000 to promote research and prevention of IDD. Appropriate objects for applications may range from limited interventions or research projects by young scientists to recognition of lifetime achievement by senior investigators. A jury of 14 international experts on IDD, chaired by Professor F. Delange, will evaluate all proposals. Application forms can be obtained from A.L.G.E.P.A., 55 Boulevard Pereire, 75017 Paris, France, FAX 33 1 45 91 51 99.

Abstracts

A ROLE FOR NONGOVERNMENTAL ORGANIZATIONS IN MONITORING THE IODINE CONTENT OF SALT IN NORTHERN INDIA. C. S. Pandav, S. Pandav, K. Anand, S. A. Wajih, S. Prakash, J. Singh, M. G. Karmarkar, All India Institute of Medical Sciences, New Delhi, Bulletin of the World Health Organization 73:71-75, 1995.

This paper assessed the iodine content of salt at the household and retail levels in iodine-deficient areas of Uttar Pradesh, and the feasibility of using NGO's to carry out this monitoring. The authors identified one agency in each of three regions to coordinate work of the NGO's at the village level. Methodology was worked out between coordinators and NGO's, and personnel were trained in collection, transport, and analysis of salt samples. The aim in each village was to collect a sample every month for six months from a particular household in the poorest section and from a particular shop, samples to be sent to regional laboratories and their iodine content determined by titration. In the three districts a total of 4000 samples were obtained, 82% from households, the rest from shops. Of these, 65% had less than 15 ppm, 21% had 15-30, and 15% had more than 30 ppm. The range was from 0 to 95 ppm. The NGO's reported little knowledge of the importance of iodized salt, even among district officials. Some improvement in knowledge occurred as a result of the contact with the NGO. The approach using NGO's appeared practical. Several features, however, need to be considered in further approaches. Shop keepers and villagers were generally reluctant to provide salt samples. Some salt was available only in packed form, making sample procurement difficult. The source of samples from open sacks could not be clearly determined. In some areas, a salt supply is obtained once yearly, by barter, and details of price and date are difficult to obtain. Shop keepers felt threatened when information about the iodine content of their salt was given to households. The authors recommend that an education campaign be conducted before monitoring is undertaken, that shop keepers be reassured that they are not threatened or being put to blame, and that training for district officials is necessary.

THYROID VOLUME AND MORPHOLOGY AND URINARY IODINE EXCRETION IN A DANISH MUNICIPALITY. B. Nygaard, P. Gideon, H. Dige-Petersen, N. Jespersen, K. Solling, A. Veje. Copenhagen, Denmark, Acta Endocrinologica 129:505-510, 1993.

The authors studied 391 women of four distinct ages (15, 30, 45, and 60 years) from the municipality of Holbaek in Denmark. Overall, 39% had goiter, by the older WHO system, and 16% had goiter of grades I or greater. The following are data for the different age groups, first the median thyroid volume (in ml), followed by daily urinary iodine excretion (mg/day): 15 years, 12 ml, 65 mg; 30 years, 18 ml, 88 mg; 45 years, 18 ml, 97 mg; and 60 years, 18 ml, 93 mg. The thyroid volume for the combined groups was 16 ml and the median urinary iodine excretion 83 mg/day. There was a poor relationship between ultrasound and palpation. Small glands were correctly diagnosed in 92%; however, 11% of the subjects had thyroid volumes above 28 ml although over half of these were not recognized by palpation. Fifteen percent of the women had structural changes in the thyroid, chiefly multinodularity, increasing with age. Women who smoked more than 10 cigarettes a day had a median thyroid volume 33% greater than nonsmokers. No correlation was found between thyroid volume and urinary iodine excretion. A useful table summarizes other studies of thyroid volume and urinary iodine, contrasting data from Sweden (volume 6.9 ml, urinary iodine 173 mg I/g creatinine) with those from Germany (19.2 ml, 62 mg/g). The authors suggest an "optimal" thyroid volume of about 10 ml (or lower) in adults. They estimate that at least 5% of Danish women need treatment for thyroid disease related to iodine deficiency. Data from the study support a recommendation for iodine supplementation for groups such as this, because of their large thyroid size.

EFFICACITE D'UN SYSTEME D'IODATION DE L'EAU DANS LA LUTTE CONTRE LES TROUBLES DUS A LA CARENCE IODEE EN AFRIQUE CENTRALE. D. Yazipo, L. F. Ngaindiro, L. Barriere-Constantin, L. Namboua, E. Pichard, J. Ndoyo, P. Bourdoux. Bangui, Central African Republic, Cahiers Sante 5:9-17, 1995 (English translation provided by Rhone Poulenc).

The study area was Nana-Grebizi, 300 km north of Bangui. The population of approximately 85,000 subsist on agriculture. Cassava is a major foodstuff. Iodized salt was not available and traditional salt making from natron and leaves occurred in some places. The study used the Rhodifuse water iodization system, based on porous polymer matrices through which sodium iodide diffuses continuously, calculated to release approximately 2 mg of NaI per hour for a period of one year. By adjusting the number of matrices, an iodine concentration of at least 5 mg/dl in the water can be obtained, thus an inhabitant ingesting 2-3 liters of water per day obtains 100-150 mg of iodine. The diffusion systems were placed in 198 bore hole wells distributed throughout the area, nine iodine matrices in each. The study group consisted of 3090 subjects in 14 villages assessed before insertion of the iodine infusion system and six and 12 months later. The initial goiter prevalence was 60.9% (total), 10.7% (visible). 0.7% of the subjects were classified as cretins. After 12 months the total goiter prevalence was 44.5%, and visible goiter 2.5%. Decrease in the younger subjects was no greater than in the older ones. No clinical evidence of thyroid dysfunction was found at 12 months. Urinary iodine levels were measured in 319 subjects, representing every 10th person in the study. The median concentration was 2.1 mg/dl initially, with 95% less than 5 mg/dl. After six months, the median was 28.9 mg/dl and at 12 months 18 mg/dl. At 12 months the urinary iodine concentration was higher than 5 mg/dl in 94% of the subjects. The median iodine concentrations in water samples was 26.3 mg/dl after six months and 2.6 mg/dl after 12 months. The mean concentration of thiocyanate in the urine was 1.7 mg/dl. The authors conclude that water iodization is useful, can provide iodine within physiologic limits, and can be implemented immediately where a water supply exists.

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