MON-354 Cardiovascular Outcomes, Hospitalization, and Overall Mortality In Patients Undergoing Thyroidectomy, Radioactive iodine, or Antithyroid Medications For Hyperthyroidism

Abstract Disclosure: G. Flocco: None. N. Vigneswaramoorthy: None. A. Sanko Posada: None. D. Al-Husni: None. A. Cheema: None. A. Vignarajah: None. W. Marcos Valencia: None. Hyperthyroidism can significantly increase the risk of cardiovascular complications. In this study, we aim to compare incidence of cardiovascular events, hospitalization, and overall mortality among patients with a diagnosis of thyrotoxicosis who undergo either thyroidectomy (T), radioactive iodine (RAI), or antithyroid medication (AM) treatment. Using the TriNextX health research database, we identified two cohorts of patients older than 18 years old with a diagnosis of thyrotoxicosis, Cohort 1 included 8,404 patients who underwent thyroidectomy, cohort 2 included 173,453 patients who were treated either with methimazole, propylthiouracil, or radioactive iodine therapy. Propensity score matching adjusted for key demographics and comorbidities resulted in 6,939 matched pairs. Measure of association analysis and Kaplan-Meier survival analysis were conducted for a 5 year follow up period after index event (T, RAI, AM). Outcomes included occurrence of hospitalization, death within 5 years, and incidence of cardiac arrest, heart failure, cerebrovascular accident, cardiogenic shock, and acute MI. The analysis showed that thyroidectomy (Cohort 1) was associated with a lower incidence of hospitalizations: 994 vs 1,148 patients, with an odds ratio of 0.843 (95% CI 0.769,0.925), and was also associated with lower all-cause mortality: 138 vs 302 patients (OR 0.446, 95% CI 0.364, 0.547), and lower incidence of all cardiovascular complications: cardiac arrest in 29 vs 52 patients (OR .556, 95% CI 0.352,0.877), HF in 106 vs 184 patients (OR 0.570, 95% CI 0.447,0.725), CVA in 197 vs 202 patients (OR 0.975, 95% CI 0.799,1.189), cardiogenic shock in 12 vs 27 patients (OR 0.443, 95% CI 0.224, 0.876), and acute MI in 108 vs 143 patients (OR 0.751, 95% CI 0.584, 0.967). The data obtained in this large U.S study show that patients with hyperthyroidism undergoing thyroidectomy experience less adverse cardiovascular outcomes, hospitalizations, and overall mortality in the 5-year period following treatment compared to patients who are treated with either radioactive iodine or antithyroid medication. Prospective studies are needed to confirm these results. Presentation: Monday, July 14, 2025