Long-term retreatment outcomes after definitive management of Graves' disease with radioactive iodine versus surgery.

BACKGROUND

Common treatments for Graves' disease include antithyroid drugs (ATD), radioactive iodine (RAI), and surgery. RAI avoids surgical morbidity, but rate and durability of remission varies across studies. This study directly compared the long-term results of Graves' disease treated by surgery versus RAI and hypothesized that RAI would be associated with lower rates of long-term biochemical remission and higher likelihood of retreatment.

METHODS

This retrospective cohort study included individuals diagnosed with Graves' disease who were treated surgically, with RAI, or both at a tertiary referral center. Definitive retreatment was defined as additional RAI or surgery after index treatment, and retreatment was defined as requiring ATD or a second definitive treatment after index treatment. Remission was defined by normalization of thyroid stimulating hormone without retreatment at 6 months.

RESULTS

Index definitive therapy was total thyroidectomy for 72 patients and RAI for 104 patients. The median follow-up time was 3.6 years. The rate of remission at 6 months in the RAI group (68.8%) was lower than that in the surgery group (98.6%) (odds ratio: 0.03, P < .001). Patients who underwent index RAI experienced a significantly higher cumulative incidence of any retreatment at all time points than those who underwent index surgery (P < .001). Among RAI patients who achieved euthyroidism within 6 months, 19% developed subsequent relapse requiring ATD therapy or retreatment.

CONCLUSION

The need for retreatment after index therapy for Graves' disease is significantly lower after thyroidectomy than after RAI.