title: Sevelamer hydrochloride improves hyperphosphatemia in hemodialysis patients with low bone turnover rate and low intact parathyroid hormone levels.
abstract: Sevelamer improves hyperphosphatemia without increasing the calcium load. However, it remains unknown whether sevelamer restores bone metabolism in hemodialysis patients with low bone turnover osteodystrophy and hypoparathyroidism. We investigated the changes in serum intact parathyroid hormone (iPTH) and bone metabolic marker levels after replacing calcium carbonate with sevelamer in these patients. We also conducted stratified analysis based on patient background and multivariate analysis to determine the factors affecting these parameters. During sevelamer replacement therapy, serum calcium and phosphate concentrations, and the calcium phosphate product were measured at 0, 1, 3, and 6 months. Serum iPTH, bone alkaline phosphatase and osteocalcin concentrations were measured at 0 and 6 months. In hemodialysis patients (71 men and 46 women, 63 +/- 12 years old) serum calcium levels and the calcium phosphate product decreased significantly at 1 month. Serum iPTH, bone alkaline phosphatase and osteocalcin levels increased significantly at 6 months. Increases in serum iPTH concentrations were observed in all stratified groups. Significant increases in serum bone alkaline phosphatase and osteocalcin concentrations were found only in the relative hypoparathyroidism group (iPTH levels > or =51.5 pg/mL, the median pretreatment level). Multivariate analysis showed that the factors affecting change in serum iPTH level are baseline serum iPTH, baseline calcium level (> or =9.5 mg/dL), and dialysis duration of 10 years or longer. Sevelamer appears useful for the treatment of hyperphosphatemia in these patients. Particularly, in the relative hypoparathyroidism group, the iPTH secretory response is probably enhanced and bone turnover may have been improved as a result of reducing the calcium load.
authors.affiliation: Department of Medical Science and Cardiorenal Medicine, Yokohama City University Graduate School of Medicine, Yokohama City, Japan.
authors.forename: Toshiharu
authors.initials: T
authors.lastname: Kokuho
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Toya
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Kawaguchi
authors.forename: Koichi
authors.initials: K
authors.lastname: Tamura
authors.forename: Kousaku
authors.initials: K
authors.lastname: Iwatsubo
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Dobashi
authors.forename: Akiko
authors.initials: A
authors.lastname: Nakazawa
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Takeda
authors.forename: Mizuka
authors.initials: M
authors.lastname: Iwatsubo
authors.forename: Nobuhito
authors.initials: N
authors.lastname: Hirawa
authors.forename: Gen
authors.initials: G
authors.lastname: Yasuda
authors.forename: Toshimasa
authors.initials: T
authors.lastname: Ohnishi
authors.forename: Satoshi
authors.initials: S
authors.lastname: Umemura
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000378:metabolism; D001842:Bone and Bones / Q000378:metabolism*; D002118:Calcium / Q000097:blood; D002130:Calcium Phosphates / Q000378:metabolism; D005260:Female; D006801:Humans; D054559:Hyperphosphatemia / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood*; D010710:Phosphates / Q000097:blood; D011073:Polyamines / Q000627:therapeutic use*; D012044:Regression Analysis; D006435:Renal Dialysis; D000069603:Sevelamer
chemical_list: D015415:Biomarkers; D002130:Calcium Phosphates; D010281:Parathyroid Hormone; D010710:Phosphates; D011073:Polyamines; C020243:calcium phosphate; D000069603:Sevelamer; D002118:Calcium