Re-evaluation of risks associated with hyperphosphatemia and hyperparathyroidism in dialysis patients: Recommendations for a change in management

Hyperphosphatemia is a predictable consequence of chronic renal failure and is present in most patients on dialysis. Traditionally, the risk associate d with elevated serum phosphorus has focused on its impact on renal osteody strophy. A growing body of evidence, however, suggests that abnormalities i n serum phosphorus, calcium-phosphorus product (CaxP), and parathyroid horm one (PTH) levels are resulting in vascular and visceral calcification, ther eby contributing to the substantially increased risk of cardiovascular deat h in this population. In this analysis, we review in detail the literature that describes these associations. We show that the current treatment parad igm for serum phosphorus and secondary hyperparathyroidism is ineffective f or a large segment of dialysis patients. Currently, 60% of hemodialysis pat ients have phosphorus greater than 5.5 mg/dL, and 40% have CaxP greater tha n 60 mg(2)/dL(2). It is our belief that prevention of uremic calcification, cardiac death, and vascular disease should assume primary importance when evaluating the risks associated with elevated levels of phosphorus, CaxP, a nd PTH. We recommend that target levels should become 9.2 to 9.6 mg/dL for calcium, 2.5 to 5.5 mg/dL for phosphorus, less than 55 mg(2)/dL(2) for CaxP product, and 100 to 200 pg/mL for intact PTH, (C) 2000 by the National Kid ney Foundation, Inc.