Effect of low-calcium dialysate on low-turnover renal osteodystrophy in elderly patients with maintenance hemodialysis

Abstract

Objective To study the effects of low-calcium dialysate on the calcium-phosphorus metabolism, parathyroid function and vascular calcifications in elderly patients with low turnover renal osteodystrophy undergoing maintenance hemodialysis (MHD). Methods 80 MHD elderly patients (aged≥60 years) who were in stable condition over 6 months and with two consecutive serum intact parathyroid hormone (iPTH) <100 ng/L were observed for 12 months and randomly classified into the control group (calcium 1.50 mmol/L of dialysate, n=40) and the treatment group (calcium 1.25 mmol/L of dialysate, n=40). The changes of serum iPTH, calcium, phosphorus, calcium and phosphorus product and other indicators as well as related adverse reactions were observed and recorded before and 1, 3, 6 and 12 months after treatment. In addition, the intima-media thickness (IMT) of carotid artery and abdominal aorta calcification score (AACS) were measured in the patients before and 6 and 12 months after treatment. Results In the treatment group, serum corrected calcium, phosphorus, and calcium-phosphate product began to decline after 1 month and a further decline at 3 months later, and serum iPTH level was significantly increased after 1 month and gradually increased at 3 months later. The above markers were stabilized after 6 months of treatment, and there were significant differences in the changes of the above markers before and after treatment (all P 0.05). Conclusions The low calcium dialysate (1.25 mmol/L) can prominently control the levels of serum calcium, phosphorus and calcium-phosphorus product, effectively improve the over-suppressed parathyroid function and vascular calcifications, and has a good security in elderly MHD patients with serum iPTH concentration <100 ng/L. Key words: Kidney failure, chronic; Hemodia filtration; Parathyroid hormone; Hemodialysis solutions