SAT452 Efficacy Of I-131 Treatment Dosage For Hyperthyroidism With Current Institution Formula

Abstract

Abstract Disclosure: S. Salam: None. N. Nso: None. M. Nassar: None. R. Kondaveeti: None. S. chings: None. -131 (radioactive iodine) therapy effectively targets overactivity of the thyroid gland; however, literature provides conflicting outcomes regarding dosage optimization of I-131 for patients with hyperthyroidism and associated clinical complications. This retrospective study aimed to validate the therapeutic efficacy of an empirically derived I-131 institution formula in resolving hyperthyroidism by establishing a euthyroid or a hypothyroid state. Methods: This retrospective chart review was undertaken for 89 adult patients (>18 years) who received I-131 therapy from 2016 to 2020 at H&H/Queens, New York. The I-131 dose range was determined in accordance with their thyroid gland weight and thyroid uptake percentages; however, the follow-up assessment was performed for the duration of 6 months. The primary endpoint (i.e., treatment success) was defined by the interim development of a euthyroid state, or hypothyroidism, or subclinical/questionable/suspected hypothyroidism, or questionable euthyroid state. The secondary endpoints included the frequency of repeat RAI doses and post-ablation thyroid function tests (TFTs). Results: The univariate and multivariate analysis of patient data indicated an 83% I-131 treatment success rate defined by the achievement of a euthyroid state and hypothyroidism in 6.7% and 70.8% of patients along with the attainment of questionable euthyroid status, questionable hypothyroidism, subclinical hypothyroidism, and suspected hypothyroidism in 1.1%, 1.1%, 2.2%, and 1.1% of patients, respectively. In addition, a low number (i.e., 9%) of patients with hyperthyroidism required repeat I-131 treatment dosages to achieve a hypothyroid or euthyroid state. The results indicated a clinically significant impact of I-131 treatment dosages on post-ablation TSH, T3, and FT4 levels. Conclusion: The results of this study testified to the therapeutic efficacy of the current institution formula for I-131 treatment dosages in treating hyperthyroidism. In addition, 83% treatment success and a low retreatment requirement strengthened current evidence favoring the optimization of RAI therapy for hyperthyroidism. Presentation: Saturday, June 17, 2023