Use of thyroid hormones in hypothyroid and euthyroid patients: A THESIS questionnaire survey of Serbian physicians

Introduction/Objective. Hypothyroidism is a common disease and treatment with levothyroxine (LT4) is effective. However, variations in management are frequent. The aim of this study was to identify practices and attitudes of Serbian physicians relating to the treatment of hypothyroidism. Methods. An anonymized questionnaire was distributed electronically to members of the Serbian Thyroid Society, Serbian Association of Endocrine Surgeons, and Section for Endocrinology of the Serbian Medical Society. Results. Out of 170 invitations, 99 responses were received. LT4 was the first choice for the treatment of hypothyroidism in 90% of patients. After starting LT4 replacement therapy most respondents would recheck thyroid-stimulating hormone (TSH) in 4–6 weeks (n = 51, 62%) and in eight weeks (n = 29, 35%). In total, 61% of respondents (n = 60) indicated that they would consider treating euthyroid patients with LT4, the commonest indication being female infertility with high levels of thyroid antibodies (54%, n = 50). More than half respondents (58%, n = 45) would recommend combined LT4 + LT3 therapy for patients on LT4 with normal serum TSH who still complain of symptoms of hypothyroidism. 53% (n = 41/77), reported that the frequency of patients with normal serum TSH who still complain of hypothyroid symptoms is less than 5%. Conclusion. LT4 was the first choice of therapy for the treatment of hypothyroid patients, whereas LT3 + LT4 combination treatment is considered in patients with persistent symptoms of hypothyroidism despite normalization of TSH. The most common indication for thyroid hormone treatment in euthyroid patients was female infertility with high levels of thyroid antibodies. Alternative LT4 formulations like liquid solution or soft-gel capsules –formulations presently not available in Serbia, were largely reserved for specific conditions (interfering drugs, malabsorption, inability to take LT4 in the fasting state, unexplained poor biochemical control of hypothyroidism).