The Use of Thyroid Hormones in Hypothyroid and Euthyroid Patients: A THESIS* Questionnaire Survey of Turkish Physicians

Objective: The incidence of diagnosis of hypothyroidism and the use of thyroid hormones are pro- gressively increasing worldwide. The availability of different thyroid hormone replacement formula- tions and combinations provides clinicians with various therapeutic choices. The aim of this survey is to document the current approaches of clinicians who manage patients with hypothyroidism in Turkey.

Methods: Members of the Society of Endocrinology and Metabolism of Turkey were invited to take part in a web-based survey.

Results: A total of 741 members, all clinicians, were invited to respond, and 193 (26%) of them com- pleted the survey. Nearly all (95.9%) participants responded that they treat hypothyroid patients daily. All participants declared that the first treatment of choice for hypothyroidism is levothyroxine. Half of the participants (50.3%), 51.1%, responded that they would not consider using levothyrox- ine + liothyronine combination in routine clinical practice. Soft and liquid forms of levothyroxine (LT4) were not used as an alternative to tablets although about a quarter of clinicians responded that they would use them if marketed in Turkey. Although 39.4% of respondents estimated that the frequency of patients with persistent symptoms despite achieving euthyroid biochemistry had increased in the last 5 years, two-thirds of them (63.2%) stated that this group comprised less than 10% of all treated hypothyroid patients. Just under half of the respondents (40.3%) would consider thyroid hormone replacement in bio- chemically euthyroid patients. The commonest indication (25% of responders) for commencing thyroid hormone therapy in euthyroid patients was female infertility with high level of thyroid per- oxidase antibodies. Only 6.8% of participants considered levothyroxine therapy for the treatment of simple goiter.

Conclusion: Levothyroxine in tablet form is the treatment of choice for hypothyroidism in Turkey. Despite the absence of robust evidence, half of the clinicians indicated their preference for levothy- roxine + liothyronine treatment in specific clinical scenarios. At variance with current guidelines, half of all clinicians would also consider levothyroxine replacement in euthyroid patients, especially thy- roid peroxidase antibodies-positive females with infertility.

Cite this article as: Ayvaz G, Akarsu E, Attanasio R, et al. The use of thyroid hormones in hypothyroid and euthyroid patients: A THESIS* questionnaire survey of Turkish physicians. Turk J Endocrinol Metab. 2022;26(2):85-91.