Analysis of demographic and clinical factors affecting the outcome of radioiodine therapy in patients with hyperthyroidism

INTRODUCTION The influence of demographic and clinical factors on the outcome of (131)I therapy in hyperthyroid patients has been examined, based on a retrospective evaluation of results obtained in patients submitted to (131)I treatment at the Department of Nuclear Medicine and Oncological Endocrinology, Medical University of Lodz (Province Hospital, Zgierz). The goal of the study was to analyse such factors as the age and sex of patients, disease duration, as well as the hormonal status before (131)I application, which could have an influence on the effects of therapy with radioiodine (131)I. MATERIAL AND METHODS The study involved 500 randomly selected patients with hyperthyroidism, treated with (131)I radioiodine. The following 3 groups were defined: group 1 - patients with multinodular goitre (MNG), n = 200; group 2 - patients with a single autonomous nodule of the thyroid (AFTN), n = 100; group 3 - patients with Graves' disease (GD), n = 200. The local ethics committee (in the Polish Mother's Memorial Hospital - Research Institute, Lodz) approved the study. RESULTS The obtained results indicate that the efficacy of therapy with (131)I applied in patients with MNG, AFTN and GD does not depend on either patient sex or patient age. The length of antithyroid treatment before (131)I therapy onset does not appear to have any effect on the therapy outcome, and the baseline thyrotropin concentration seems to be significant only in the case of GD. CONCLUSIONS The analysed demographic factors do not affect the outcome of (131)I therapy in hyperthyroidism.