About the Disease

There are over 300,000 stage 5 CKD dialysis patients in the United States. ^[1] These patients have limited or no kidney function and depend on dialysis, along with dietary restrictions and phosphate binders to minimize serum phosphorus. Hyperphosphatemia has been shown to significantly increase patient mortality and morbidity. ^[2] Phosphorus control is critical to the quality of care for dialysis patients.

Hyperphosphatemia is managed through dialysis, diet modification and utilization of phosphate binders to inhibit absorption of dietary phosphorus. Due to the limitations of dialysis and the challenges of dietary phosphorus restriction, almost all dialysis patients rely on a phosphate binder to reduce phosphorus absorption and prevent hyperphosphatemia. While effective in controlling phosphorus, traditional phosphate binders may lead to problems such as increased incidence of hypercalcemic episodes or metal toxicity affecting the brain, bones and other body systems. ^[3,4]

Because stage 5 CKD patients have systems that are essentially “closed,” accumulation of calcium and metals is a greater concern for these patients who do not have the capacity to excrete these elements. When evaluating phosphate binders, the consequences of calcium and metal accumulation should be considered. The intake of calcium and metal in the form of a binder presents one more challenge to systems that are already compromised.

References

1. USRDS 2003 ADR
2. Block GA, Hulbert-Shearon TE, Levin NE, Port FK. Association of Serum Phosphorus and Calcium x Phosphorus Product with Mortality Risk in Chronic Hemodialysis Patients: A National Study. Am J Kidney Dis. 1998;31:607-617.
3. Chertow GM. Poly[allylamine Hydrocloride]: A Noncalcemic Phosphate Binder for the Treatment of Hyperphosphatemia in Chronic Renal Failure. Am J Kidney Dis. 1997;29:66-71.
4. Burke SK. Renagel a Novel calcium-and aluminum-free phosphate binder, inhibits phosphate absorption in normal volunteers. NDT. 1197;8:1640-1644