Correlation Between Metabolic Acidosis and Bone Mineral Density in Pre-Dialysis Chronic Kidney Disease

Abstract

Background: Chronic kidney disease is associated with metabolic acidosis and disturbances in bone mineral metabolism that contribute to skeletal fragility. Objective: To evaluate the correlation between serum bicarbonate levels and bone mineral density in patients with pre-dialysis chronic kidney disease. Methods: This cross-sectional analytical study was conducted at a tertiary care hospital and included 103 adult patients with CKD stages 1–5. Biochemical parameters including serum bicarbonate, phosphate, calcium, and intact parathyroid hormone were measured. Bone mineral density at the lumbar spine and femoral neck was assessed using dual-energy X-ray absorptiometry. Correlation analysis was performed to determine associations between biochemical markers and BMD indices. Results: Serum bicarbonate demonstrated significant positive correlations with lumbar spine T-score (r=0.315, p=0.001), lumbar spine Z-score (r=0.267, p=0.006), femoral neck T-score (r=0.199, p=0.044), and femoral neck Z-score (r=0.233, p=0.018). Serum phosphate showed a moderate positive correlation only with femoral neck T-score (r=0.304, p=0.002). Serum calcium and iPTH showed weak, non-significant associations with BMD. Conclusion: Higher serum bicarbonate levels are associated with better bone mineral density in pre-dialysis CKD, suggesting a clinically relevant link between metabolic acidosis and skeletal health.