Abstract: Objective To compare the efficacy of lanthanum carbonate and calcium acetate with low phosphorus dietary on hyperphosphatemia among patients on peritoneal dialysis (PD). Methods PD patients with hyperphosphatemia treated in the PD center of our hospital between Dec. 2014 and May 2015 were
recruited into this study according to the inclusion and exclusion criteria. They were randomized into lanthanum carbonate group and calcium acetate group. Low calcium dialysate was prescribed appropriately during the study period. The drug doses were adjusted according to serum calcium and phosphorus levels. Serum calcium, phosphorus and intact parathyroid hormone were compared at baseline, after the treatment for one month, 2 months and 3 months. Dietary phosphorus intake, and phosphorus removed from urine and dialysate were measured. Results A total of 51 patients were recruited and randomized into lanthanum carbonate group (n=25) and calcium acetate group (n=26). They completed the study except for 3 patients who dropped out due to gastrointestinal symptoms. At the end of the study, lanthanum carbonate was 1500 (750～1875) mg/d and calcium acetate was 2001 (2001～4002) mg/d. Demographic data, biochemistry parameters, and dialysis adequacy were similar at baseline between the two groups. In the study period of 3 months, serum phosphorus
decreased significantly in both groups, and the changes of serum calcium (F=1.122, P=0.293), phosphorus (F=1.118, P=0.732) and iPTH (F=1.638, P=0.206) had no differences between lanthanum carbonate group and calcium acetate group. After the education about dietary phosphorus restriction, lower phosphorus
intake from dietary maintained during the study period in both groups. The net phosphorus accumulations at the baseline and at the 3rd month of therapy were similar between lanthanum carbonate group and calcium acetate group [at baseline: 175.98 (84.12～414.93) vs. 256.66 (101.15～443.74), t=2.065, P=0.735; at the 3rd month: 418.74 (214.04～531.20) vs. 361.0 (210.48～394.37), t=0.965, P=0.349]. Conclusion By the appropriate use of lower phosphorus dietary and low calcium dialysate for PD, both lanthanum carbonate and calcium acetate treatment could effectively decrease serum phosphorus of similar extent. No extra risk of higher serum calcium was observed in calcium acetate group.

Key words: Peritoneal dialysis, Hypophophatemia, Lanthanum carbonate, Calcium acetate