Three therapies exist for Graves disease (also known as Graves hyperthyroidism): antithyroid drug therapy (ATD), radioactive iodine (I131 therapy) to damage the thyroid or surgery to remove all or part of the thyroid. The efficacy of each of these treatments is well known; however, little is known about the long-term outcomes of each treatment modality. A new study in Thyroid presents long-term (6–10 years) outcome data for the different treatments of Graves disease.

Credit: J. Vallis/Springer Nature Limited

The researchers recruited a cohort of 2,430 patients with newly diagnosed Graves disease from 13 endocrine clinics in Sweden in 2003–2005. Patients were followed up for 8 ± 0.9 years (mean ± s.d.) after diagnosis. By reviewing the medical records of each patient and by conducting questionnaires, information was obtained on the treatment modality, patient demographic, lifestyle factors, rate of disease remission, quality of life and the presence of comorbidities.

The proportion of patients that were available at follow-up was 60% (1,186 individuals). The first-line treatment of choice was ATD, followed by I131 therapy and then surgery. However, the remission rate after the first-line treatment was 45.3% (351/774) with ATD, 81.5% (324/264) with I131 therapy and 96.3% (52/54) with surgery.

Notably, if ATD-treated patients with disease recurrence underwent a second round of ATD, the rate of remission was even lower (29.4%). Moreover, patients treated with ATD as a first-line therapy (with potential additional rounds of ATD) had a 49.7% risk of having either I131 therapy or surgery (that is, ablative treatment) at follow-up. This situation is far from ideal, as it exposes patients to additional risks of adverse events from each treatment.

Of note, normal thyroid hormone status, without replacement with levothyroxine, was only achieved in 35.7% of all patient groups after follow-up. Moreover, 25.3% of patients did not feel fully recovered at follow-up.

the remission rate after the first-line treatment was 45.3%

The researchers conclude that patients who select ATD as a first-line treatment should be informed that they have only a 50.3% chance of avoiding ablative treatment and only a 40% chance of being euthyroid long term.