Bone Abstracts

Bone mineral density (BMD) changes were estimated in kidney recipients. In 63 patients aged 24–64 years, measured creatinine clearance at the end of the first posttransplant year was >50 ml/min and remained stable over the study period, bone mineral density (BMD) was estimated in the lumbar spine, femoral neck, Ward’s triangle and the distal third of the radius using dual energy absorptiometry (DEXA) 0.1–4, 12–18 and 23–36 months after transplantation. IPTH, Ca and Pi were measured 1–8, 12–18 and 23–36 months posttransplant. BMD changes (delta BMD, ±%) between measurements were calculated per 12 months. Data are given as median, lower and upper quartile. Delta BMD (±%/12 months): i) first: second measurement; lumbar spine −3.02 (−5.91, 0.001), femoral neck −1.94 (−6.66, 3.70), Ward’s triangle −3.9 (−2.5, −0.9), distal radius −1.3 (−3.34, 0.16), ii) second: third measurement; lumbar spine 1.76 (−0.96, 4.24), femoral neck 1.82 (−0.56, 5.13), Ward’s triangle 0.495 (−4.86, 6.95), distal radius −0.87 (−2.65, 1.13). Delta BMD for radius did not differ significantly between two observational periods. Dialysis duration prior to transplantation correlated significantly negatively with radius T and Z scores at all measurements. PTH correlated significantly negatively with femoral neck BMD at first measurement. IPTH was higher in patients who lost radial BMD between the first and second measurement than in those who did not. IPTH values did not differ significantly between measurements. During the first posttransplant year, the majority of patients lost cortical and trabecular bone. For cortical bone, this trend continued after this period. Dialysis vintage prior to transplantation was a risk factor for cortical bone loss. Hyperparathyroidism influenced bone negatively.