CKD-Mineral Bone Disorder in Stage 4 and 5 CKD: What We Know Today?

Patients with CKD stages 4 and 5 experience biochemical derangements associated with CKD-mineral bone disorder. Some of the key abnormalities are hyperparathyroidism, hyperphosphatemia, hypocalcemia, and metabolic acidosis. We review the available treatments for these conditions and the evidence behind the treatments. We conclude that there is greater evidence for treating hyperphosphatemia than hyperparathyroidism. Treatment of metabolic acidosis in small clinical trials appears to be safe. We caution the reader about side effects associated with some of these treatments that differ in patients with CKD Stages 4 and 5 compared with patients on dialysis. The use of cinacalcet has been associated with hyperphosphatemia in patients with functioning kidneys. Activated vitamin D therapy has been associated with elevated creatinine levels, which may or may not be a reflection of true decrement in kidney function. Finally, the use of non-calcium-containing phosphate binders may be associated with improved clinical outcomes in patients; however, many more clinical trials are needed in this important area of medicine.