Arterial calcification in chronic kidney disease

Hyperphosphatemia is associated with soft-tissue calcification and bone disease. Nephrologists prescribe phosphate binders to decrease dietary phosphate absorption, reduce serum phosphorus concentrations, and minimize the risk for soft-tissue calcification and bone disease. Recent data suggest that the dose of calcium used as a phosphate binder may contribute to the risk for cardiovascular calcification. Chronic positive calcium balance from diet, dialysis, and calcium-based phosphate binders or intermittent hypercalcemia may favor precipitation of calcium and phosphate into tissues. Calcium suppresses parathyroid hormone (PTH) secretion and bone turnover, limiting the ability of bone to incorporate calcium and phosphorus. Sevelamer, a nonabsorbed polymer, allows physicians to bind dietary phosphate and decrease serum phosphorus without unwanted absorption of metals or calcium or oversuppression of PTH. In a comparative trial, calcium-based phosphate binders were associated with progressive coronary artery and aortic calcification that was attenuated by sevelamer. The optimal phosphate binder is one that controls hyperphosphatemia prevents soft-tissue calcification and preserves bone health.

Keywords:  hyperphosphatemia , sevelamer , calcium , calcification , bone disease