Calcium acetate versus calcium carbonate in the control of hyperphosphatemia in hemodialysis patients.
BACKGROUND
Hyperphosphatemia has an important role in the development of bone and mineral abnormalities in end-stage renal disease (ESRD).


OBJECTIVE
To compare the phosphorus binding power and the hypercalcemic effect of calcium acetate and calcium carbonate in hemodialysis patients.


METHODS
Crossover, randomized, double-blind study.


METHODS
A private hospital dialysis center.


METHODS
Fifty-two patients who were undergoing regular hemodialysis three times a week ([Ca++] dialysate = 3.5 mEq/L).


METHODS
Half of the patients were started on 5.6 g/day of calcium acetate and, after a 2 week washout period, received 6.2 g/day of calcium carbonate. The other half followed an inverse protocol.


METHODS
Clinical interviews were conducted 3 times a week to monitor for side effects. Determinations of serum urea, calcium, phosphorus, hematocrit, Kt/V and blood gas analysis were obtained before and after each treatment.


RESULTS
Twenty-three patients completed the study. A significant increase in calcium plasma levels was only observed after treatment with calcium carbonate [9.34 mg/dl (SD 0.91) vs. 9.91 mg/dl (SD 0.79), P < 0.01]. The drop in phosphorus levels was substantial and significant for both salts [5.64 mg/dl (SD 1.54) vs. 4.60 mg/dl (SD 1.32), P < 0.01 and 5.89 mg/dl (SD 1.71) vs. 4.56 mg/dl (SD 1.57), P < 0.01, for calcium acetate and calcium carbonate respectively]. The percentage reduction in serum phosphorus (at the end of the study) per milliequivalent of salt administered per day tended to be higher with calcium acetate but statistical significance was not found.


CONCLUSIONS
Calcium acetate can be a good alternative to calcium carbonate in the handling of hyperphosphatemia in ESRD patients. When calcium acetate is used, control of hyperphosphatemia can be achieved with a lower administration of calcium, perhaps with a lower risk of hypercalcemia.
d'Almeida Filho
E J
EJ
Universidade Federal Fluminense, Niterói, Brazil.
da Cruz
E A
EA
Hoette
M
M
Ruzany
F
F
Keen
L N
LN
Lugon
J R
JR
D000085:Acetates / Q000009:adverse effects / Q000627:therapeutic use*; D000328:Adult; D000704:Analysis of Variance; D000863:Antacids / Q000009:adverse effects / Q000627:therapeutic use*; D002119:Calcium Carbonate / Q000009:adverse effects / Q000627:therapeutic use*; D018592:Cross-Over Studies; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D010760:Phosphorus Metabolism Disorders / Q000188:drug therapy* / Q000209:etiology; D006435:Renal Dialysis / Q000009:adverse effects*
D000085:Acetates; D000863:Antacids; D002119:Calcium Carbonate