Long Term Efficacy of Radioiodine Treatment in Hyperthyroidism

Abstract

Objective:

Radioiodine is the mainstay of the treatment of thyroid hyperfunction. However, it is difficult to apply the appropriate amount of radioidone to achieve optimal efficacy with the least possible adverse effects. Results of the investigation on the efficacy of a relatively new protocol for radioiodine treatment of hyperthyroidism are reported.

Design:

A retrospective evaluation of data from 326 patients with a mean average follow-up of 5.7 (1.0–11.7) years was performed. 64% of these patients suffered from Graves’ disease and 36% had uni- or multinodular toxic goitre.

Results:

In Graves’ disease, the recurrence rate was 5% 1 year after the treatment, and that remained the same after 5 years. In toxic goitre, these rates were 6 and 7%, respectively. After 5 years 70% of the patients with autonomous adenomas were euthyroid, while 78% of the Graves patients developed hypothyroidism and 17% showed euthyroid state. A relationship between the lack of normalisation of thyroid-stimulating hormone levels after radioiodine treatment and the increased recurrence of late hyperthyroidism has also been established in patients with Graves’s disease.

Conclusion:

Compared to the available data published in the literature, the success rate of the treatment is fairly high confirming the effectiveness of our protocol.

Key words

Graves’ disease - toxic adenoma - radioiodine therapy

^* These authors contributed equally to this work.

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