Decrease in Thoracic Vertebral Bone Attenuation With Calcium-Based Phosphate Binders in Hemodialysis

Abstract

The average serum phosphorus and calcium x phosphorus products were similar for both groups, although the average serum calcium concentration was significantly higher in the calcium-treated group. Compared with sevelamer-treated subjects, calcium-treated subjects showed a decrease in thoracic vertebral trabecular bone attenuation (p = 0.01) and a trend toward decreased cortical bone attenuation. More than 30% of calcium-treated subjects experienced a 10% or more decrease in trabecular and cortical bone attenuation. On study, sevelamer-treated subjects had higher concentrations of total and bone-specific alkaline phosphatase, osteocalcin, and PTH (p < 0.001). When used to correct hyperphosphatemia, calcium salts lead to a reduction in thoracic trabecular and cortical bone attenuation. Calcium salts may paradoxically decrease BMD in hemodialysis patients.