Goitre epidemiology: thyroid volume, iodine excretion, thyroglobulin and thyrotropin in Germany and Sweden

Thyroid volume of 1397 German and 303 Swedish adults were estimated by sonography. Thyroid size of 6-16 year old Germans (n = 619) was determined and compared with findings on palpation. Thyroid volume was more than twice as great in German (21.4 +/- 15.6 ml, mean +/- SD) than in Swedish adults (10.1 +/- 4.9 ml). The echopattern was abnormal in 16% of the Germans and in 3.6% of the Swedes. German children have a thyroid volume ranging from 1.8 +/- 0.4 ml at 6 years to 10.8 +/- 6.0 ml at 16 years of age. Palpation is by comparison an unreliable method for determining thyroid size. In Germany, the iodine excretion was less in children (n = 619, 39.5 +/- 30.5, 34.1 micrograms I/g creatinine, mean +/- SD, median) than in adults (n = 1193, 83.7 +/- 94.4, 62.6), (P less than 0.001) and much lower than that observed in Sweden (adults n = 98, 170.2 +/- 93.3, 141.4; 13 year olds n = 113, 172.9 +/- 224.1, 124), (P less than 0.0001). Serum thyrotropin concentration was significantly higher (P less than 0.001) in Sweden (n = 62, 1.49 +/- 0.82 mU/ml), than in Germany (n = 91, 0.97 +/- 0.52 mU/ml), while serum thyroglobulin was increased in Germany (n = 91, 72.6 +/- 50.6 micrograms/l) as compared to Sweden (n = 62, 23.5 +/- 17.4), (P less than 0.0001). These results indicate the goitrogenic effect of iodine deficiency and the continuing need for an effective iodine prophylaxis in the FRG.