[Toxic adenomas of the thyroid gland becoming less frequent in Berne]

The frequency distribution of immunogenic and non-immunogenic hyperthyroidism (IH, NIH) was evaluated retrospectively in the former endemic goiter area of Berne over a 15-year period (1976, 1982, and 1991). Out of 12,320 patients referred for thyroid examinations, 9.1% were hyperthyroid. NIH still predominates with a constant frequency of 59%; but the ratio between toxic adenomas (TA) and multifocal functional autonomies (MFA) was significantly inversed, from 2.6 over 0.9 to 0.4. The frequency of TA decreased from 41% to 17% and that of MFA increased from 16% to 38%. The arithmetic mean age at diagnosis was constant: 53.9 (IH), 61.5 (TA) and 67.5 years (MFA). The decreasing frequency of TA over the last 15 years is explained by an increased but still insufficient iodine supply.