Epidemiologic estimation of goiter in children from Gdańsk, Elblag, Olsztyn and Toruń districts (Gdańsk coordinating center).

The study comprised 1604 children (49.9% of boys and 50.1% of girls) of age between 6 and 13 years living in the districts of Gdańsk, Elblag, Olsztyn and Toruń. 55.5% of children were from urban area, 44.5% from rural area. This districts have been divided into 3 geographic regions. 1) Olsztyn region: 174 children and the villages near Olsztyn--178 children, 2) Seaside region: Gdańsk and Elblag--358 children and 3 villages situated in the distance less than 60 km from the sea--533 children, 3) Toruń region: Toruń--181 children and villages near Toruń--180 children. A significant relationship between the incidence of goiter and the place of living was found. The presence of goiter was observed in 9.2% of children in Gdańsk and Elblag and in 23% of children in the seaside region (with the peak in Glincz village--35%). In Olsztyn region the incidence was 18.2%, in Toruń region--12.5%. Among 1604 studied subjects in 263 (16.4%) with goiter, the nodular goiter was in 2.3% of cases. The lowest occurrence of goiter was noted in Gdańsk and Elblag. Urinary iodine concentration in children with goiter from Gdańsk and Elblag (123.1 micrograms/l) was higher than in those living in villages in the seaside region (90.8 micrograms/l). The thyroid size as measured by ultrasonography was different in children with and without goiter in each age group. In the age group of 6-8 years it was 4.8 ml in children without goiter and 6.3 ml in children with goiter, in the age group 9-10 years, 5.7 ml and 8.6 ml, in the age group 11-12 years, 6.6 ml and 10.0 ml, in children 13 years old--8.0 ml and 12.1 ml. All the children with goiter have greater body weight and height than those in the same age groups without goiter. 13.2% of studied persons consumed iodized salt. There was no difference in the incidence of goiter in children receiving and not receiving iodized salt (13.4% and 13.1% in all regions). There was also lack of relation between urinary iodine concentration and rate of consumption of iodized salt.