Bone mineral density in chronic kidney disease patients

Abstract

Background: Metabolic bone disease is common in the case of renal failure. The aim of this study is to compare mineral changes, hormonal changes and bone mineral density in pre-dialysis and post-dialysis renal failure patients. Hypothesis: Secondary hyperparathyroidism may be the cause for skeletal changes in renal failure. Materials and Methods: 20 patients of both sexes, with chronic kidney disease formed the subjects of the present study. Studies are done in pre and post dialysis states. In this study bone mineral density is measured by dual energy X-ray absorptiometry and bone minerals are estimated by using standard lab techniques. Results and Conclusion: The results of this study indicate no gross variation in both genders in all parameters. The serum calcium levels (P-0.073) are statistically decreased. In contrast, serum phosphorus levels (P-0.98) are raised but statistically not significant. Parathyroid hormone levels (P-0.50) are increased but statistically not significant. Vitamin D3 levels (P-0.02) are significantly increased in post dialysis compared to pre-dialysis subjects. Bone mineral density in lumbar spine (L1 to L4) T-Score (P-0.007), Z–Score (P-0.009), neck of the femur T-Score (P<0.001), Z–Score (P-0.008) statistically decreased. The forearm T-Score (P-0.97), Z–Score (P-0.12) indicates small variation and statistically not significant. The mineral changes are mainly due to increased secretion of parathyroid hormone. Dialysis has no effect in bone mineral density. There is skeletal resistance to parathyroid hormone, due to reduction in number of hormone receptors and decreased level of calcitriol and loss of negative feedback on parathyroid hormone secretion by calcitriol.