Epidemiology and factors associated with mortality of thyroid storm in Taiwan

Thyroid storm is a rare and life-threatening disease. However, its prevalence, incidence, and mortality rate in Chinese population are unknown. We performed a retrospective study using the Taiwan Health and Welfare Data. Patients admitted owing to thyrotoxicosis were divided into thyroid storm group and non-thyroid storm group. We assessed thyroid storm prevalence, incidence, complications, and mortality rate. Multiple Cox regression was performed to estimate the hazard ratio for the mortality risk. Overall, 1244 thyroid storm patients and 83,874 thyrotoxicosis patients without thyroid storm were included. Most thyroid storm patients were female (67.9%) with ages ranging from 30 to 44 years (33.4%), and most thyroid storm cases occurred during the summer season. The prevalence of thyroid storm was 1.48% (1244/83,874). The incidence rate of thyroid storm was 0.55 per 100,000 persons per year and 6.28 per 100,000 hospitalized patients per year. The overall 14-, 28-, and 90-day mortality rates of thyroid storm patients were 5.23%, 6.59%, and 8.12%, respectively. Thyroid storm, older age, male, and underlying ischemic stroke, myocardial infarction, heart failure, kidney disease, atrial fibrillation, depression, chronic obstructive pulmonary disease, diabetes mellitus, cancer, end stage renal diseases were associated with a significantly higher risk of mortality. In conclusion, the 90-day mortality rate of thyroid storm was high and was commonly associated with multiorgan failure and shock. Therefore, clinical physicians should identify thyroid storm and treat it accordingly.