The clinical value of regular thyroid function tests during amiodarone treatment

作者:Benjamens Stan; Dullaart Robin P F; Sluiter Wim J; Rienstra Michiel; van Gelder Isabelle C; Links Thera P*
来源:European Journal of Endocrinology, 2017, 177(1): 9-14.
DOI:10.1530/EJE-17-0018

摘要

Objective: Amiodarone is used for the maintenance of sinus rhythm in patients with arrhythmias, but thyroid dysamiodarone-induced thyrotoxicosis (AIT) or amiodarone-induced hypothyroidism (AIH)) is a common adverse effect. As the onset of AIT and AIH may be unpredictable, the value of long-term regular monitoring of amiodarone treated patients for thyroid dysfunction is still uncertain. Design: We retrospectively documented the frequency at which overt thyroid dysfunction was preceded by subclinical thyroid dysfunction. Methods: We included 303 patients treated with amiodarone between 1984 and 2007. AIT was defined as a lowered TSH level with an elevated free thyroxine (FT4) and AIH was defined as an elevated TSH level with a decreased or subnormal FT4. Subclinical AIT was defined as a lowered TSH level with a normal FT4 and subclinical AIH as an elevated TSH level with a normal FT4. Results: 200 men and 103 women, aged 62 +/- 12.0 years, suffering from atrial (260) or ventricular (43) arrhythmias, were evaluated. During a median follow-up of 2.8 (1.0-25) years, 44 patients developed AIT and 33 AIH. In 42 (55%) patients who developed AIT/AIH, earlier thyroid function tests showed no subclinical AIT or subclinical AIH. In 35 (45%) patients, AIT/AIH was preceded by subclinical AIT or subclinical AIH (16/44 for AIT and 19/33 for AIH). Conclusions: In a considerable proportion of patients who developed AIT/AIH, earlier thyroid function tests showed no subclinical AIT/AIH. Less than half of the patients with a subclinical event subsequently developed overt AIT/AIH. This study provides data to reconsider the yield of regular testing of thyroid function to predict overt thyroid dysfunction in amiodarone treated patients.

  • 出版日期2017-7