Endocrine Abstracts

Background: Graves’ disease is widely treated with anti-thyroid medication. After an initial course of treatment, remission is achieved in around 50% of patients. Definitive treatment is generally offered in relapsed cases, based on the assumption that remission rates following a second course of anti-thyroid medication are significantly lower.

Method: A database of patients with Graves’ disease has been kept from 2004. 150 patients were suitable for inclusion. Retrospective data was collected on: age at diagnosis, ethnicity, gender, smoking status, family history, presence of goitre, eye signs, treatment type and outcome. Data analysis was focused on the second course of anti-thyroid medication and its outcome.

Results: 133 of 150 patients opted to undergo an initial course of anti-thyroid treatment (6–34 months). 71 of 133 (53%) patients relapsed. Of these 71 patients, 34 opted for a second course of medical therapy. Of these, 1 was lost to follow-up and 2 remain on long-term treatment. Of the 31 remaining patients, 11 (35%) remained in remission at one year following treatment withdrawal; 14 relapsed and 6 are still undergoing treatment. Comparing those who went into remission with those who relapsed after a second course, significant findings were: age range 30–60 years versus 22–46 years; 9 of 11 versus 6 of 14 females; 4 of 11 versus 8 of 14 had a goitre; 7 of 11 versus 6 of 14 relapsed after 12 months; fT4 range 15.0–39.9 pmol/L versus 22.8–80.1 pmol/L on relapse.

Conclusions: Although there was probably a selection bias, our data suggests that a number of individuals are suitable for a second course of anti-thyroid treatment, with at least 35% remission rate. Factors suggestive of a greater chance of remission include older age, female gender, lack of goitre, and less severe thyroid function tests on first relapse.

Declaration of interest: There is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported.

Funding: No specific grant from any funding agency in the public, commercial or not-for-profit sector.