Prevalence and Risk Factors for Thyroid Eye Disease among Korean Dysthyroid Patients

PURPOSE To determine the prevalence of thyroid eye disease among dysthyroid Korean patients and to analyze the relationship between demographic data, lifestyle risk factors, and status of thyroid disease and thyroid eye disease. METHODS All dysthyroid patients who visited endocrinology clinics in 24 general hospitals in Korea during a chosen one-week period were enrolled in this cross-sectional study. Data were collected during an interviewer-administered questionnaire and chart review. Demographic data, lifestyle risk factors, and status of thyroid disease variables were analyzed as risk factors using multivariable regression models to identify independent associations with thyroid eye disease. RESULTS A total of 1,632 dysthyroid patients were included (1,301 females [79.7%] and 331 males [20.3%]). Two hundred eighty-three of these patients (17.3%) had thyroid eye disease. Multiple logistic regression analyses revealed that female gender, young age, Graves' disease, dermopathy, anti-thyroid medication treatment, and radioiodine treatment were independent risk factors for thyroid eye disease. CONCLUSIONS The lower prevalence of thyroid eye disease in dysthyroid Korean patients and the influence of gender on risk factors in this study are novel findings compared to studies performed involving Europeans. Although the risk factors for thyroid eye disease are understood in part, a more in-depth comparative study of gender and ethnic groups is needed to fully understand the biological significance of the demographic factors.