Long-term follow-up of treatment outcomes in Graves' disease and toxic nodular disease.

PURPOSE

Hyperthyroidism guidelines have not been updated over the past five years, despite numerous data on the subject, and recent studies providing a wide variation in treatment success rates. We aim to compare the effectiveness and safety of treatment modalities in patients with Graves' disease or toxic nodular disease.

METHODS

Single center retrospective cohort study of Graves' disease and toxic nodular disease patients treated between 1983 and 2023.

RESULTS

A total of 411 patients were treated for hyperthyroidism, 245 due to Graves' disease and 166 due to or toxic nodular disease, followed for a median of 7 years. In Graves' disease, 90.2% were treated with antithyroid drugs over 250 cycles, achieving 41.7% cumulative remission. Half of all relapses (50.9%) occurred in the first year, 76.3% in the first three years, and 98.3% within nine years. Treatment periods of 12-24 months showed higher remission and lower relapse rates than longer periods. I-131 was used in 103 cycles with 82.5% remission and 7.1% relapse. A total of 29 thyroidectomies resulted in 100% remission, with no relapse. In toxic nodular disease, surgery was the most frequently used treatment (54.5%), followed by I-131 (37.1%).

CONCLUSION

Our findings support antithyroid drugs as the preferential first-line treatment for Graves' disease, allowing for euthyroidism with minimal adverse effects. Given the propensity for relapse, we suggest a rigorous monitoring, particularly within the first three years. In toxic nodular disease, surgery should be the preferred option, with I-131 being reserved for single adenomas and small goiters.