Greater Efficacy of Total Thyroidectomy versus Radioiodine Therapy on Hyperthyroidism and Thyroid-Stimulating Immunoglobulin Levels in Patients with Graves’ Disease Previously Treated with Antithyroid Drugs

Abstract

Aims: We compared the effects of total thyroidectomy (TTx) and radioiodine (RAI) administration on the course of thyroid hormones and thyroid-stimulating immunoglobulins (TSI) in patients with Graves’ disease. Methods: We retrospectively studied 80 patients initially treated with antithyroid drugs and requiring either RAI (8.3 ± 1.7 mCi of ¹³¹I; n = 40) or TTx (n = 40) as second-line therapy. Results: The TTx and RAI groups were not different, except for larger goiter, higher FT₃ and more frequent Graves’ orbitopathy at diagnosis in the surgery group (p < 0.05). A persistent remission of hyperthyroidism was observed in 97% of operated patients versus 73% of the RAI patients at 3 years (p < 0.01). TTx was followed by a rapid and steady decrease in TSI during the first 9 months, while a surge of antibodies was observed during the first 6 months after RAI, followed by a slow decrease over the next 18 months. At the last visit, high TSI levels were still observed in 18 and 60% of patients in the surgery and RAI groups, respectively (p < 0.001). Conclusions: TTx is more efficient than RAI to induce a rapid and permanent correction of hyperthyroidism and TSI decrease in patients previously treated with antithyroid drugs.