[Endemic goiter in Austria's youth?].

After 17 years the efficiency of iodine prophylaxis of endemic goiter (1 : 100000) in Austria was checked by control field studies in 3 Tyrolean towns n Austria. The data obtained there were compared with those of 123 school age children from the iodine deficient endemic goiter area of the province of Bolzano (Italy). The results show a reduction in goiter incidence from 50 to 35% in the total population in Austria, where goiter incidence in schoolchildren dropped from 45.9% to 12%. Urinary iodine/g creatinine was 65 micrograms in Austria, the 24 hr radioiodine uptake with 41.8% was normal. In comparison the ethnologically and geographically similar endemic goiter zone in the province of Bolzano showed a goiter incidence in schoolchildren of up to 46%, while urinary iodine/g creatinine was 35.9 micrograms and radioiodine uptake after 24 hr about 50%. Extensive studies of peripheral hormone parameters (T4, TBG, T3, TSH, rT3, FT3, FT4) revealed a significantly higher rT3 concentration of 24.7 ng/dl in Austria compared with a value of only 19.8 ng/dl in the province of Bolzano. These facts suggest an increased conversion of T4 to real T3 in iodine deficiency, which might contribute to the adaptation of the organism to this condition. No statement, however, can be presented regarding the regulation of this phenomenon. Even as endemic goiter is decreasing in Austria, an increase of salt iodization to 1 : 50000 according to the swiss procedure might eliminate definitely endemic goiter in Austria.