Long-term outcomes of treatment of hyperthyroidism in Ireland

We investigated the long-term outcome of treatment in 159 patients with hyp erthyroidism first seen between 1979 and 1992. Median duration of follow-up was 10 1/2 years. We also enquired into current practice for the follow-up of hyperthyroidism by other endocrinologists in Ireland. Seven cases of unrecognised hyperthyroidism (4 per cent) and one of unrecog nised hypothyroidism were identified. Among patients with Graves' disease, of those treated with an antithyroid drug, 28 per cent were in remission, 6 8 per cent had relapsed and 4 per cent had become hypothyroid. Of those tre ated by sub-total thyroidectomy, 31 per cent were in remission, 19 per cent had relapsed, 19 per cent were hypothyroid and 31 per cent were sub-clinic ally hypothyroid. Among patients treated with radioiodine, 19 per cent were euthyroid, 3 per cent were still hyperthyroid and three-quarters had becom e hypothyroid. In contrast, after radioiodine for toxic nodular goitre, 63 per cent were euthyroid and only 32 per cent had become hypothyroid (Chi Sq uared v. Graves' disease, P = 0.001). Of 73 patients receiving thyroxine replacement, plasma TSH was normal in on ly 41 per cent, although 82 per cent of patients had been seen by the famil y doctor within the previous 12 months. Seven of 17 other endocrinologists undertook long-term follow-up of hyperthyroid patients in their specialist clinics but none was using a computerised system to co-ordinate this. The f indings confirm that careful follow-up is required for all hyperthyroid pat ients. The family doctor is well positioned to undertake this, but educatio n and auditing are required.