Bone Abstracts

Objectives: Metabolic bone disease is a frequent complication of end-stage renal disease, characterised by a decreased bone mineral density, which can be measured with dual-energy X-ray absorptiometry. Its validity as a marker for clinical bone disease and increased fracture risk has never been established in adults with pediatric onset of end-stage renal disease (1–3). Adult survivors of pediatric end stage renal disease have very low bone mineral density and small stature (4). In this cohort study, the association between low bone mineral density measured with dual-energy X-ray absorptiometry in adult survivors of pediatric end-stage renal disease in 2000 and manifestations of clinical bone disease between 2000 and 2010 was assessed.

Methods: 113 from all 187 living patients of the so called LERIC-cohort (4) agreed to participate. Data regarding bone mineral density and clinical bone disease were gathered in 2000. Volumetric bone mineral density was calculated. Data on clinical outcome were gathered retrospectively by reviewing medical charts over the period 2000–2010 and by questionnaires.

Results: Mean volumetric bone mineral density Z-scores (95% CI) of the lumbar spine was −1.0 (−1.2 to −0.7) and femoral neck was −3.0 (−3.5 to −2.5). 27% of the patients suffered from clinical bone disease. 16 patients (14%) had suffered from a fracture in the last 10 years, of which four were pathological fractures. The odds ratios (95% CI) of volumetric bone mineral density for clinical bone disease and fractures over 10 years were 1.033 (0.867 to 1.231) and 0.679 (0.437 to 1.055) respectively.

Conclusion: Adult survivors of pediatric end stage renal disease have low volumetric bone mineral density and the prevalence of clinical bone disease is high. However, we found no significant association between bone mineral density and clinical bone disease. Therefore, the usefulness of dual-energy X-ray absorptiometry in predicting clinical bone disease in patients with pediatric end-stage renal disease is still uncertain.