Search

Objective: The monitoring of the populations' iodine status is an essential part of successful programmes of iodine deficiency elimination. The current study aimed at the evaluation of current iodine nutrition in school children, pregnant and lactating women as a marker of the effectiveness and sustainability of mandatory iodine prophylaxis in Poland., Design: The following iodine nutrition indicators were used: urinary iodine concentration (UIC) (all participants) and serum thyroglobulin (pregnant and lactating women)., Setting: The study was conducted in 2017 within the National Health Programme in five regions of Poland., Participants: The research included 300 pregnant women, 100 lactating women and 1000 school children (aged 6-12 years)., Results: In pregnant women, median UIC was 111·6 µg/l; there was no significant difference in median UIC according to the region of residence. In 8 % of pregnant women, thyroglobulin level was >40 ng/ml (median thyroglobulin 13·3 ng/ml). In lactating women, median UIC was 68·0 µg/l. A significant inter-regional difference was noted (P = 0·0143). In 18 % of breastfeeding women, thyroglobulin level was >40 ng/ml (median thyroglobulin 18·5 ng/ml). According to the WHO criteria, the investigated sample of pregnant and lactating women was iodine-deficient. Median UIC in school children was 119·8 µg/l (with significant inter-regional variation; P = 0·0000), which is consistent with iodine sufficiency. Ninety-four children (9·4 %) had UIC < 50 µg/l., Conclusions: Mandatory iodisation of household salt in Poland has led to a sustainable optimisation of iodine status in the general population. However, it has failed to assure adequate iodine nutrition during pregnancy and lactation.

Background: Knowledge about the population's iodine status is important, because it allows adjustment of iodine supply and prevention of iodine deficiency. The validity and comparability of iodine-related population studies can be improved by standardization, which was one of the goals of the EUthyroid project. The aim of this study was to establish the first standardized map of iodine status in Europe by using standardized urinary iodine concentration (UIC) data. Materials and Methods: We established a gold-standard laboratory in Helsinki measuring UIC by inductively coupled plasma mass spectrometry. A total of 40 studies from 23 European countries provided 75 urine samples covering the whole range of concentrations. Conversion formulas for UIC derived from the gold-standard values were established by linear regression models and were used to postharmonize the studies by standardizing the UIC data of the individual studies. Results: In comparison with the EUthyroid gold-standard, mean UIC measurements were higher in 11 laboratories and lower in 10 laboratories. The mean differences ranged from -36.6% to 49.5%. Of the 40 postharmonized studies providing data for the standardization, 16 were conducted in schoolchildren, 13 in adults, and 11 in pregnant women. Median standardized UIC was <100 μg/L in 1 out of 16 (6.3%) studies in schoolchildren, while in adults 7 out of 13 (53.8%) studies had a median standardized UIC <100 μg/L. Seven out of 11 (63.6%) studies in pregnant women revealed a median UIC <150 μg/L. Conclusions: We demonstrate that iodine deficiency is still present in Europe, using standardized data from a large number of studies. Adults and pregnant women, particularly, are at risk for iodine deficiency, which calls for action. For instance, a more uniform European legislation on iodine fortification is warranted to ensure that noniodized salt is replaced by iodized salt more often. In addition, further efforts should be put on harmonizing iodine-related studies and iodine measurements to improve the validity and comparability of results.

Introduction: A frequency in excess of 5% of goitre in children is an approved WHO marker of iodine deficiency. As thyroid ultrasound remains the main method of thyroid volume (TV) assessment, the choice of adequate normative values is important for the proper interpretation of epidemiologic data. There is disagreement as to whether local or international normative values should be used. The aim of this study was to establish Polish local TV normative values in children aged 6-12 years., Material and Methods: The study was carried out in a group of 642 children aged 6-12 years (312 girls and 330 boys) living in the Polish seaside area with a proven history of best iodine supply. Inclusion criteria were: iodine concentration in casual morning urine samples above 100 μg/L, no goitre on palpation, no pathological findings on thyroid US, no history of thyroid disorders, no treatment affecting thyroid function, and written informed consent from the child's parents. TV was measured ultrasonographically with a 7.5 MHz linear transducer. Urinary iodine concentration (UIC) was measured in urine spot samples using the Sandell-Kolthoff method., Results: Median UIC ranged according to age from 126.6 to 155.1 μg/L in girls, and from 132.23 to 157.62 μg/L in boys. TVs at P97 were: 3.96, 4.23, 4.33, 5.44, 6.07, 9.5, and 10.9 for girls and 3.99, 4.2, 4.79, 6.61, 7.38, 7.89, and 9.35 for boys. They were lower than the 1997 WHO normative values but higher than the 2004 reference currently adopted by the WHO., Conclusions: The obtained results may be adopted as normative TV values for Polish children.