Benefits of Sevelamer on Markers of Bone Turnover in Taiwanese Hemodialysis Patients

Background/Purpose: Sevelamer hydrochloride is a recently developed phosphate binder, which is a quaternary amine anion exchanger without calcium or aluminum. Sevelamer is effective in controlling hyperphosphatemia without increasing the calcium load in chronic hemodialysis D) patients. We investigated whether sevelamer restored bone metabolism in chronic HD patients. Methods: An 8-week, prospective, open-label, randomized study was conducted after a 2-week washout period in chronic hyperphosphatemic HD patients. This study compared the effect of sevelamer on markers of bone turnover with that of calcium acetate, as stratified by baseline serum intact parathyroid hormone (iPTH) level. Results: There was no difference in the changes of serum phosphorus, calcium-phosphorus product and serum iPTH between the sevelamer and the calcium acetate groups. However, more hypercalcemic events (12%) were documented under calcium acetate treatment. In patients with hypoparathyroidism, calcium acetate treatment decreased serum iPTH at the end of the study, while sevelamer did not. Increased serum alkaline phosphatase levels were found among patients receiving sevelamer treatment compared with those who received calcium acetate treatment. In those patients receiving sevelamer, the serum alkaline phosphatase level was also positively correlated to the sevelamer dosage (r=0.246, p=0.013). Conclusion: Sevelamer effectively reduces serum phosphorus with a lower incidence of hypercalcemic effects in HD patients. Sevelamer is an effective means of treatment for chronic hyperphosphatemic D patients, especially those with hypoparathyroidism.