Iodine deficiency disorders in the north-eastern region of Poland (Białystok coordinating center).
This epidemiologic survey was carried out during the period between November 1992 and February 1993. Altogether 1431 children of age between 6 and 13 years from randomly selected 4 rural and 4 city schools were included into the study. The measurements of body height and weight, estimation of thyroid size by palpation and by USG were performed in every case. Urine was also sampled to measure iodine concentration with cerium-arsenic method. In 39.1% of the examined children goiter was found by physical examination and was more frequent in the rural group (41%) than in the urban children (36%). Mean iodine concentration in the urine was significantly higher in the group with goiter (52.7 micrograms/l) than in the group without goiter (42.3 micrograms/l) No symptoms of hypothyroidism were observed in the studied group. Moreover the presence of goiter had no influence on physical development of the children. According to the questionnaires, iodized salt is used by 26% of children in the cities and 16% in the villages. Neither iodine level in the urine nor prevalence of goiter was markedly affected by iodine prophylaxis. We conclude that the north-eastern region of Poland in an area of a moderate iodine deficiency and that the present model of iodine prophylaxis is insufficient.