Effect of lanthanum carbonate on phosphate control in continuous ambulatory peritoneal dialysis patients in Korea: a randomized prospective study

Hyperphosphatemia is a common complication in end-stage renal disease (ESRD) patients. Reducing the serum phosphate level is crucial in management of ESRD.This study was a randomized prospective study, designed to compare patients with hyperphosphatemia undergoing peritoneal dialysis while taking lanthanum carbonate or calcium carbonate. We divided 72 continuous ambulatory peritoneal dialysis (CAPD) patients whose serum phosphate levels were over 5.6 mg/dl into two groups to receive either lanthanum carbonate or calcium carbonate. Serum calcium, phosphate and PTH levels were examined serially for 24 weeks.Both lanthanum carbonate and calcium carbonate reduced serum phosphate levels, from 6.79 ± 1.05 to 5.44 ± 1.44 and from 6.31 ± 1.13 to 4.74 ± 0.78 mg/dl, respectively. The calcium × phosphate product level was reduced in the lanthanum carbonate and calcium carbonate groups from 60.23 ± 10.23 to 46.97 ± 16.42 and from 57.92 ± 11.05 to 44.50 ± 7.74 mg2/dl2, respectively. The serum parathyroid hormone (PTH) level in the lanthanum carbonate group did not change significantly compared to baseline during the study, but in the calcium carbonate group, the serum PTH level decreased significantly. Gastrointestinal complications were the main adverse effects of lanthanum carbonate and 11 out of 35 patients dropped out of the study due to this complication.Lanthanum carbonate was as effective as calcium carbonate in reducing serum phosphate level, and serum PTH level tended to be steadier in the lanthanum carbonate group compared to the calcium carbonate group. Though the ifference was not significant, lanthanum carbonate tended not to elevate serum calcium level in CAPD patients compared to calcium carbonate. The high incidence of gastrointestinal adverse effect in the lanthanum carbonate group will need further evaluation.