Two year comparison of sevelamer and calcium carbonate effects on cardiovascular calcification and bone density.
BACKGROUND
Calcium-based phosphate binders may induce tissue calcification, and little is known about their effects on bone density. We compared the effects of a calcium with a non-calcium phosphate binder on both arterial calcification and bone density measured by computed tomography.


METHODS
Seventy-two adult haemodialysis patients were randomized to treatment with calcium carbonate (CC) or sevelamer (SEV) for 2 years. Electron beam CT scans were performed at baseline and at 6, 12 and 24 months. Serum phosphorus, calcium, calcium x phosphorus product and intact parathyroid hormone (iPTH) were measured and other routine laboratory tests were also carried out.


RESULTS
The average calcium x phosphorus product was similar in the two treatment groups. However, patients receiving CC had significantly lower average iPTH (P<0.01), were more likely to have hypercalcaemic episodes (P = 0.03) and had significantly greater increases in coronary artery (CC median 484, P<0.0001, SEV median 37, P = 0.3118, between-group P = 0.0178) and aortic (CC median 610, P = 0.0003, SEV median 0, P = 0.5966, between-group P = 0.0039) calcification scores. The CC group also had a significant decrease in trabecular bone density (CC median -6%, P = 0.0049, SEV median +3%, P = 0.0296, between-group P = 0.0025). However, there was no significant difference in cortical bone density between the two groups.


CONCLUSIONS
This 2 year study shows that calcium carbonate use is continuously associated with progressive arterial calcification in haemodialysis patients. In addition, it suggests that it is also associated with decreased trabecular bone density. However, this latter finding requires confirmation by a study specifically devoted to this issue.
Asmus
Hans-Gernot
HG
KfH Nierenzentrum Sonnenallee Berlin, Berlin, Germany.
Braun
Johan
J
Krause
Rolfdieter
R
Brunkhorst
Reinhard
R
Holzer
Herwig
H
Schulz
Walter
W
Neumayer
Hans-Hellmut
HH
Raggi
Paolo
P
Bommer
Jürgen
J
D000328:Adult; D000368:Aged; D000863:Antacids / Q000627:therapeutic use*; D015519:Bone Density / Q000187:drug effects*; D002114:Calcinosis / Q000209:etiology / Q000517:prevention & control*; D002118:Calcium / Q000097:blood; D002119:Calcium Carbonate / Q000627:therapeutic use*; D002318:Cardiovascular Diseases / Q000188:drug therapy* / Q000209:etiology; D004852:Epoxy Compounds / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood; D010710:Phosphates / Q000097:blood; D011073:Polyamines; D011095:Polyethylenes / Q000627:therapeutic use*; D006435:Renal Dialysis; D000069603:Sevelamer
D000863:Antacids; D004852:Epoxy Compounds; D010281:Parathyroid Hormone; D010710:Phosphates; D011073:Polyamines; D011095:Polyethylenes; D000069603:Sevelamer; D002119:Calcium Carbonate; D002118:Calcium