Effects of thyroid hormone replacement therapy on thyroid hormone levels and electrocardiogram changes in geriatric patients with hypothyroidism

Abstract

This paper aims to analyze the effects of thyroid hormone replacement therapy on thyroid hormone levels and electrocardiogram changes in elderly patients with hypothyroidism. 48 elderly patients with hypothyroidism admitted to our hospital from January 2014 to December 2014 were selected as subjects. All the patients were treated with thyroid hormone replacement therapy. The changes of thyroid hormone levels and ECG parameters were compared before and after treatment. After treatment, serum thyroid stimulating hormone (TSH) was significantly lower than that before treatment, and the free triiodothyronine (FT3) and free thyroxine (FT4) were significantly higher than those before treatment (t=15.587, 17.396, 19.593, P<0.05); R-R interval, QT interval, QTc interval were significantly lower than before treatment, and the Heart rate (HR), standard deviation of all normal R-R intervals (SDNN), standard deviation of 5 min average R-R intervals (SDANN) within 24h, high frequency power (HF) were significantly higher than before treatment (t=2.171, 2.354, 4.264, 3.100, 10.754, 11.467, 16.776, P<0.05). Thyroid hormone replacement therapy is helpful to improve the level of thyroid hormone and ventricular repolarization in patients with hypothyroidism, and to regulate the function of cardiac autonomic nervous system.