Endocrine Abstracts

Objectives: To evaluate outcomes post radioiodine (I-131) therapy for hyperthyroidism at a tertiary hospital in a two-year period.

Method: The local database (Leicester Clinical Workstation) was used to identify patients with hyperthyroidism who had received radioiodine therapy (RAI) between January 1^st 2010 and December 31^st 2011 and their records were retrospectively analysed.

Results: 84 patients were identified, 65 (77%) were female and 19 (23%) were male. Graves’ disease comprised 48 patients (57%), multinodular goitre 22 patients (26%), solitary toxic nodule 6 patients (7%), autonomous thyroid function of unspecified aetiology 8 patients (10%). The mean duration between first diagnosis of thyrotoxicosis and time of first radioiodine was 1507 days (range=62–6532). 14 patients (16%) had ophthalmopathy – of whom 4 were given steroids. 1 patient had worsening of existing ophthalmopathy, and 1 patient only developed clinically apparent ophthalmopathy post RAI. In both these patients the eye disease remained mild in severity. At 2 years post RAI, 59 patients (70%) were hypothyroid, 18 patients (21%) were euthyroid and 7 patients (8%) remained hyperthyroid. 5 patients went on to have a second dose of RAI and 2 patients underwent thyroidectomy. Of the 5 patients who received RAI for the second time, 3 (60%) became hypothyroid and 2 (40%) became euthyroid.

Conclusion: Overall rates of hypothyroidism (70%), euthyroidism (21%) and hyperthyroidism (8%) at 2 years were similar to previous data published by our group in 2008 (67, 27 and 6% respectively). Although only 2 patients developed worsening eye disease, this remains an important potential complication in patients with Graves’ receiving RAI. Although there were similar single centre data published previously there were no nationwide data to compare with, thus we recommend a nationwide audit into outcomes and complications post RAI for hyperthyroidism.