Bone loss in relation to renal transplantation

Abstract

ABSTRACT Background: Patients with chronic renal failure (CRF) who are going through a renal transplantation (RTx) are at high risk of experiencing bone loss and fractures. Abnormalities of the skeleton in CRF, collectively known as renal osteodystrophy, are an important cause of morbidity and decreased quality of life. In addition, bone loss occurs rapidly following renal transplantation because of aggravating factors that emerge after procedure. Among these factors, the key pathophysiological contributor to bone disease is immunosuppressive agent application, especially glucocorticoids (GC). Aim: The purpose of the present study was to examine the bone mineral density of CRF patients at the point of transplantation, and thereafter the early bone loss following transplantation by doing a prospective descriptive study. Moreover the purpose was to identify predictors of the bone status prior to and the bone loss following transplantation in these patients. Material and method: 46 patients were measured between the fifth and tenth day following RTx as baseline, and again 10 to 12 weeks later, in a descriptive longitudinal study. At both visits lumbar spine (LS), total neck (TN), total body (TB), ultra distal and proximal forearm were measured using the dual-energy X-ray absorptiometry machine Lunar Prodigy Advance. In addition, blood samples were collected for analyses of the bone markers osteocalcin and telopeptide. Questionnaires were used to gain information about variables which possibly could be implicated in bone loss. Test results from standard procedure analyses were collected from the patients journals. Results: According to the Z-scores the patients had significantly lower BMD at baseline compared to normative data. At baseline, significant determinants of low BMD were age, gender, smoking and former transplantations. A highly significant bone loss from baseline to follow-up was observed in LS, TF and TB, within the range 1.2 to 2.5 %. The significant determinants of change in BMD were age (LS), change in osteocalcin levels (TF) and CMV infection (TB), explaining about 9 %, 18 % and 10 % of the bone loss, respectively. Conclusion: The study gives further evidence to the fact that patients suffering from CRF who goes through RTx is in danger of a continuing bone loss with a major risk of bone fractures.