Patients with severe Graves’ ophthalmopathy have a higher risk of relapsing hyperthyroidism and are unlikely to remain in remission

Objective To evaluate the relationship between severity of Graves’ ophthalmopathy (GO) and relapse/remission rate of associated thyroid disease.

Patients and methods One hundred and fifty-eight patients with Graves’ disease (GD) were seen within the first 6–12 months after the onset of GO and were followed for at least 18 months. During treatment, GO was classified as mild (n = 65) or severe course (n = 93) by severity and activity scores. All patients received standard anti-thyroid drug (ATD) treatment for 1 year, and in cases of relapse another cycle of ATD, thyroidectomy or radioiodine therapy.

Results Following ATD treatment, 27 patients (42%) with a mild course of GO went into thyroid disease remission, while only seven (8%) patients with a severe course of GO achieved remission (P < 0·0001). Eventually, 32 patients (49%) with a mild course needed definitive thyroid therapy and the remaining 9% preferred another cycle of ATD. However, among patients with a severe GO course, 84% needed definitive therapy (P < 0·0001) and 8% opted for another course of ATD treatment. The probability of relapse could also be predicted by TBII levels 12 months after initiation of ATD therapy, as 96·8% of patients with TBII levels above 7·5 IU/l relapsed (odds ratio 24·3).

Conclusion Patients with severe GO and high TBII are unlikely to go into remission. This allows early decision-making regarding definitive treatment of the thyroid in GD patients with severe GO or very high TBII levels.