PREVENTION OF BONE LOSS IN CARDIAC TRANSPLANT RECIPIENTS - A COMPARISON OF BIPHOSPHONATES AND VITAMIN-D

Bone mineral density is already abnormally reduced at the moment of ca rdiac transplantation and bone loss occurs at an impressive rate in th e first postoperative year. The aim of the study was to compare two pr ophylactic medical regimens as to their efficacy in mitigating bone lo ss after transplantation. Forty-eight consecutive recipients were rand omized to receive either alternating calcium carbonate and disodium et idronate (group A) or a daily supplement of calcium carbonate and alph acalcidol (group B). Bone mineral density measurements were performed immediately before hospital discharge and 6, 12, and 24 months after s urgery using dual energy X-ray absorptiometry. Clinical events were re corded and roentgenograms of the spine were performed postoperatively and 1 and 2 years later. In both treatment groups bone Boss remained s ignificant at the level of the lumbar spine in the first postoperative year (P<0.005) and at the level of the femoral neck in the first (P<0 .005) and the second (P<0.05) year after transplantation. Six months a fter transplantation, however, patients receiving ail phacalcidol had a significant reduction in bone loss at the level of the lumbar spine (P=0.047) and at the level of the femoral neck (P=0.043). At the level of the femoral neck this decrease in bone loss was even more pronounc ed in the second postoperative year (P<0.001). In the group of patient s treated with disodium etidronate, 4 recipients needed additional hos pitalizations for treatment of symptomatic fractures at the level of t he lumbar spine or the femoral neck. No such events happened in recipi ents receiving vitamin D supplements. Prophylactic administration of c alcium carbonate and alphacalcidol after cardiac transplantation reduc es bone loss and seems to decrease osteoporotic complications.