Reductions in serum TSH and FT4 levels due to roxadustat in hemodialysis patients：A single-center retrospective study

Abstract

Recently, cases in which hemodialysis (HD) patients exhibited decreased serum thyroid-stimulating hormone (TSH) levels after the administration of the hypoxia-inducible factor-prolyl hydroxylase inhibitor roxadustat (ROX) have been reported. We investigated the frequency and severity of reductions in serum TSH and free thyroxine (FT4) levels caused by ROX in 11 HD patients (71±15 years old) who underwent maintenance HD treatment at Shirasagi Hospital, Japan. It was observed that the serum TSH levels of 9 of the 11 patients decreased during ROX treatment and were below the reference level in 3 cases. Furthermore, the serum FT4 levels of all 11 patients dropped below the reference level during ROX treatment. A strong positive correlation was found between the serum TSH fluctuations and the serum FT4 fluctuations before and after the start of ROX treatment ( ρ＝0.838, p＝0.001). In the most significant case, the patientʼs serum TSH levels had decreased from 8.81 to 1.04 μIU/mL, and their serum FT4 levels had decreased from 1.05 to 0.38 ng/dL 12 days after the start of ROX treatment. The patientʼs serum TSH and FT4 levels improved to within the normal range after the discontinuation of ROX. The results of our study suggested that ROX frequently decreases the serum TSH and FT4 levels of HD patients, and it may be necessary to pay attention to the rapid onset of the effects of ROX and related symptoms in some cases.