MO576ASSOCIATION OF BONE MATERIAL STRENGTH WITH BONE DENSITY IN PATIENTS WITH END-STAGE RENAL DISEASE

Abstract

Abstract Background and Aims Patients with end-stage renal disease (ESRD) have an increased risk of skeletal complications, including an increased fracture risk, which is only partially identified by determination of bone mineral density (BMD). Experimentally, the complex bone-and mineral disorders in ESRD cause disturbances of bone material properties, but these have not been studied in vivo. Determination of bone material strength index (BMSi) by reference point indentation (RPI) is a novel method to determine bone material quality in vivo and can identify patients at increased fracture risk, even in the presence of normal BMD. We determined BMSi in ESRD patients and investigated its association with BMD and serum markers of mineral metabolism. Method 15 Adult patients with ESRD, scheduled for a living-donor kidney transplantation, were included in this cross-sectional study. Laboratory analyses included calcium, phosphate, PTH 1-84 and alkaline phosphatase. BMSi was determined by RPI with the OsteoProbe RUO in the tibia. Bone mineral density was measured by dual X-ray absorptiometry. Results Patients with bone mineral strenght index above median had higher bone mineral density of the right hip and total body than patients below median (p = 0.04). Alkaline phosphatase was lower in patients with BMSi below the median (47 (35-71) U/L vs. 103 (53-318) U/L, p = 0.009). There was a trend towards a significant relationship between length and BMSi (p = 0.09). Conclusion We identified for the first time an association of BMSi with BMD and alkaline phosphatase in patients with ESRD. Our findings of an association of BMSi with BMD are in accordance with findings in other populations with increased fracture risk.