Effects of selenium in patients with Graves’ disease treated with antithyroid drugs

In spite of previous conflicting results, an adjuvant role of selenium in the treatment of Graves’ disease (GD) hyperthyroidism has been proposed. The aim of our study was to assess the effects of selenmethionine added to antithyroid drug therapy in patients with GD. Methods. Twenty eight newly diagnosed hyperthyroid GD (mild or moderate severity) patients were randomly assigned to treatment during 12 months with: 1) thiomazole and levothyroxine + selenium or 2) thiomazole and levothyroxine. At base line and every 3 months the levels of TSH, fT4, fT3, TPO Ab, TRAbwere measured. For the thyroid tissue echogenicity assessment thyroid ultrasound was preformed. Follow-up period lasted 18 months (12 months of anthithyroid therapy, 6 month after withdrawal of antithyroid therapy, selenium was withdrawn after 15 months of therapy). Results. There were no significant difference between the groups in biochemical restoration of hyperthyroidism, titers of TPO Ab and TRAb during the whole observational period. There were also no difference between the treatment groups in rate of relapse after the withdrawal of treatment. Conclusions. Our study, failed to show an adjuvant role of selenium in the control of hyperthyroidism in patients with newly diagnosed GD