Therapeutic efficacy and limitations of potassium iodide for patients newly diagnosed with Graves’ disease

Abstract

The efficacy of potassium iodide (KI) for Graves' disease (GD) has been reported, although few clinical reports have examined the long-term efficacy of treatment. The objective of this study was to investigate the efficacy and limitations of KI treatment for GD. This study enrolled patients newly diagnosed with mild GD, defined as free thyroxine (FT4) <5.0 ng/dL, between July 2014 and June 2016. KI was started at a dose of 50 mg/day, and if FT4 values did not decrease after initiation of treatment, doses were increased to 100 mg/day. Patients for whom thyroid hormone levels could not be controlled with KI at 100 mg/day were regarded as non-responders. Of the 122 patients (13 males, 109 females) included in this study, 71 (58.2%) responded to KI therapy. The remaining 51 patients (41.8%) were non-responders. The median duration required to judge non-responsiveness was 5.9 months. Multiple logistic regression analysis performed on parameters measured at the initial visit indicated FT4 (odds ratio (OR) 2.19, 95% confidence interval (CI) 1.28-3.75; p = 0.0007) and male sex (OR 3.58, 95%CI 1.04-12.3; p = 0.04) were significantly associated with KI responsiveness. Receiver operating characteristic (ROC) curve analysis of the relationship between FT4 and KI responsiveness indicated an FT4 cutoff of 2.76 ng/dL was optimal for differentiating between responders and non-responders. KI therapy was effective and safe for about 60% of patients with mild GD.

Asymmetrical Graves’ disease in children: potential usefulness of potassium iodide monotherapy

“…Okamura et al 20 showed that KI monotherapy was effective in 65.9% of patients with thionamide-associated side effects, with 38.6% of the patients experiencing remission after KI therapy. Suzuki et al 21 reported that KI therapy was effective and safe in almost 60% of patients with mild GD, which was defined as an FT4 level <5.0 ng/dL. Furthermore, they suggested that an FT4 cut-off of 2.76 ng/dL was optimal for differentiating between responders and non-responders 21.…”

“…Suzuki et al 21 reported that KI therapy was effective and safe in almost 60% of patients with mild GD, which was defined as an FT4 level <5.0 ng/dL. Furthermore, they suggested that an FT4 cut-off of 2.76 ng/dL was optimal for differentiating between responders and non-responders 21. Based on these findings, we chose KI monotherapy as the initial treatment in our case, as the negativity of TRAb indicated a milder clinical course and less severe side effects were preferred.…”

HLA typing of patients who developed subacute thyroiditis and Graves’ disease after SARS-CoV-2 vaccination: a case report

“…Serum antithyroglobulin antibody (TgAb) and antithyroid peroxidase antibody (TPOAb) levels were determined by ECLIA using an ECLusys Anti-Tg and Anti-TPO kit (Roche Diagnostics). Serum TRAb levels were determined by ECLIA using an ECLusys TRAb electrochemiluminescence immunoassay kit (Roche Diagnostics) [ 18 ]. Serum TSAb levels were measured using a TSAb radioimmunoassay and bioassay kit (Yamasa, Choshi, Japan).…”

Cardiac Troponin Is Elevated in Patients with Thyrotoxicosis and Decreases as Thyroid Function Improves and Brain Natriuretic Peptide Levels Decrease

“…Basically, antithyroid drugs (ATDs) were initiated for patients with hyperthyroidism. Potassium iodide was administrated in combination with ATDs for patients with severe Graves' disease [21] and as monotherapy for patients with mild Graves' disease [22]. Assessments at 3, 6, 9, and 12 months included FT 4 , FT 3 , TSH, BNP, and hsTnI.…”