THESIS (Treatment of Hypothyroidism in Europe by Specialists: An International Survey) Questionnaire Survey of Medical Thyroid Specialists in Korea on the Use of Thyroid Hormones in Hypothyroid and Euthyroid Patients.

BACKGROUND

Recent surveys have highlighted substantial variability in the management of hypothyroidism that is associated with physician demographic and geo-economic characteristics. This study aimed to assess preferences for thyroid hormone therapy among medical thyroid specialists in Korea.

METHODS

An online survey was conducted using the Treatment of Hypothyroidism in Europe by Specialists: An International Survey (THESIS) questionnaire. Participants were medical thyroid specialists who were members of the Korean Thyroid Association (KTA).

RESULTS

Among the 349 regular members of the KTA who were physicians, 53 (15.2%) completed the survey. All respondents reported prescribing levothyroxine (LT4) as the initial treatment of choice for hypothyroidism. For patients with biochemical euthyroidism, 64.2% of respondents indicated that treatment was unnecessary; however, several conditions were cited as potential indications for thyroid hormone use (multiple responses were allowed), including female infertility with elevated thyroid antibody levels (30.2%), enlarging simple goiter (17.0%), and severe hypercholesterolemia as adjunctive therapy (9.4%). Although 24.5% of respondents reported avoiding LT4+liothyronine (LT3) therapy because of low-quality evidence, 62.3% indicated that they would consider it for symptomatic patients receiving LT4 monotherapy with normal thyroid-stimulating hormone levels.

CONCLUSION

Korean thyroid specialists generally adhere to current clinical guidelines, favoring LT4 as the standard treatment for hypothyroidism. However, there is considerable willingness to use LT4+LT3 combination therapy and to prescribe thyroid hormones for certain non-thyroid conditions. Ongoing educational efforts are needed to improve understanding that many persistent symptoms despite biochemical euthyroidism are influenced by psychosocial factors and to facilitate consistent implementation of evidencebased, guideline-aligned clinical practice.