A Long Term Follow-up Study of Patients with Goitrous Hashimoto' s Disease

Abstract

To clarify the clinical course and prognosis in patients with Hashimoto's disease, thyroid function was examined in 199 patients (166 females, 33 males) about every six months for an average of 10.5 years in females and 7.5 years in males. The diagnosis of Hashimoto's disease was based on the presence of diffuse goiter, positive thyroid autoantibodies (antimicrosomal antibodies greater than or equal to 400 and/or antithyroglobulin antibodies greater than or equal to 100) and/or the typical histological findings of Hashimoto's disease in aspiration biopsy. Initially, 76 patients (38%) were euthyroid, and 123 patients (62%) were subclinical hypothyroid or overt hypothyroid. At the end of follow-up, 113 patients (57%) were euthyroid and 86 patients (43%) were permanently hypothyroid. Only 12 patients (6%) in the initially euthyroid state developed permanent hypothyroidism during the follow-up period. Transient thyroid dysfunction occurred in 35 (46%) of 76 patients who were initially euthyroid. Forty-nine (40%) of 123 patients who initially had subclinical or overt hypothyroidism were in the euthyroid state at the end of follow-up. In these recovered patients, the T3/T4 ratio and the level of T3 was higher than in non-recovered patients. The best predictive factors of final permanent hypothyroidism at the initial examination were 1) the titer of antithyroglobulin antibodies greater than or equal to 6400, 2) the titer of antimicrosomal antibodies greater than or equal to 25600, 3) age above 50 years, 4) a stony-hard goiter. Female patients who initially show three of the above predictive factors and males who show two have a high possibility of being permanently hypothyroid after 10 years. The prognosis is poorer in male than in female patients.