Treatment and management of thyroid storm: analysis of the nationwide surveys: The taskforce committee of the Japan Thyroid Association and Japan Endocrine Society for the establishment of diagnostic criteria and nationwide surveys for thyroid storm.

Objective: Thyroid storm (TS) is a life-threatening endocrine emergency. This study aimed to achieve a better understanding of the management of TS by analyzing therapeutic modalities and prognoses reported by nationwide surveys performed in Japan.

Design, Patients And Measurements: Retrospective analyses were performed on clinical parameters, outcomes, and treatments in 356 TS patients.

Results: Patient disease severities assessed via Acute Physiology and Chronic Health Evaluation (APACHE) II and Sequential Organ Failure Assessment (SOFA) scores significantly correlated with mortality. Free triiodothyronine (FT3) and the FT3/free thyroxine (FT4) ratio inversely correlated with disease severity. Methimazole (MMI) was used in the majority of patients (78·1%), and there were no significant differences in mortality or disease severity between those treated with MMI and those receiving propylthiouracil (PTU). Patients who received inorganic iodide (KI) demonstrated higher disease severity but no change in mortality compared to those who did not. Patients treated with corticosteroids (CSs) demonstrated significantly higher disease severity and mortality than those who were not. Disease severity in patients treated with intravenous administration of beta-adrenergic antagonists (AAs) was significantly higher than those treated with oral preparations, although no significant difference in mortality was observed between these groups. In addition, mortality was significantly higher in patients treated with non-selective beta-AAs as compared with other types of beta-AAs.

Conclusion: In Japan, MMI was preferentially used in TS and showed no disadvantages compared to PTU. In severe TS, multimodal treatment, including administration of antithyroid drugs, KI, CSs and selective beta1 -AAs may be preferable to improve outcomes.