Endocrine Abstracts

Introduction: Antithyroidal drug (ATD) therapy is considered as choice of treatment for Graves’ disease; however, the response of treatment varied between patients. Although several studies reported risk factors for relapse after initial treatment, there were few studies for the responsiveness during early treatment period.

Method and design: We reviewed 94 patients with Graves’ disease and used their initial TSH receptor antibody (TSHRAb) titre and consequent free T4 levels during follow up periods. Drug responsiveness was defined as the correlation coefficients between decreasing rates of free T4 levels and exposed dose of ATD. We analysed and compared the coefficients of each patient according to clinical characteristics and TSHRAb titre.

Results: The mean age of subjects was 47.1±15.4 years old and male patients were 26 (28%). The mean titre of initial TSHRAb was 19.1±14.0 IU/L. Although the correlation coefficients did not showed significant association with age group (≤40, 41~60, 60<) and sex, higher titre of TSHRAb was associated with better responsiveness (−0.13±0.10 vs. −0.16±0.16 vs. −0.22±0.13, respectively in three groups (≤10, 10.1~20, 20<)). We could also observe significant correlation between the consequent TSHRAb titre and the responsiveness.

Conclusion: Our results suggest the possible usage of TSHRAb titre to decide the optimal initial ATD dose and its adjustment in early treatment periods.