The effect of iatrogenic subclinical hyperthyroidism on anxiety, depression and quality of life in differentiated thyroid carcinoma

Abstract

Background/aim: Overt thyroidism is known to cause neuropsychiatric disorders but studies on subclinical hyperthyroidism (SCH) arelimited. Subclinical hyperthyroidism induction by administering L-Thyroxine (LT4) is the standard treatment method in differentiatedthyroid carcinoma (DTC) follow-up. Our aim was to investigate whether anxiety, depression and quality of life are affected in DTCpatients followed-up with exogenous SCH.Materials and methods: The patients were divided into exogenous SCH by LT4-DTC (n = 127), euthyroid-DTC (n = 66) and exogenouseuthyroid-benign thyroid noduüle (BTN) who underwent thyroidectomy for benign thyroid pathology (n = 85) groups.Results: The rate of moderate/severe anxiety was significantly higher in SCH-DTC than euthyroid-BTN group (27.5%, n = 35 vs. 9.4%, n= 8) (P = 0.001). TSH levels and Beck anxiety inventory (BAI) scores were significantly negatively correlated(P = 0.009 r = –0.16). FreeT4 and BAI were significantly positively correlated (P = 0.04 r = 0.4). The groups were similar in terms of depression severity (P = 0.15).Subclinical hyperthyroid-DTC group scored significantly lowerthan euthyroid-BTN group in all scales of SF-36 quality of life survey.Conclusion: LT4-induced SCH, which is a part of traditional DTC treatment, can exacerbate the anxiety symptoms in patients anddisrupt their quality of life, depending on the level of fT4.