Adherence to phosphate binder therapy is the primary determinant of hyperphosphatemia incidence in patients receiving peritoneal dialysis.

We investigated the major determinant of hyperphosphatemia incidence among patients receiving peritoneal dialysis. Seventy-six patients aged 25-55 years who had received peritoneal dialysis for more than 3 months were recruited. The patients were divided into three groups according to their serum phosphorus levels (Group 1, ≥ 6 mg/dL; Group 2, 5.9-4.8 mg/dL; and Group 3, <4.8 mg/dL). Renal dietitians interviewed the patients to determine their phosphate intake and adherence to phosphate binder therapy. No statistical differences in demographics or phosphate intake were identified among the groups. However, adherence to phosphate binders was greater in Group 3 than in Groups 1 and 2 (96.3% vs. 21.4% and 52.4%, respectively; P < 0.001). Multivariate analysis showed that adherence to phosphate binder therapy was the only significant contributor to serum phosphorus levels (P= 0.0001). Adherence to diet was better than adherence to phosphate binder therapy among patients receiving peritoneal dialysis, and the latter determined the incidence of hyperphosphatemia.