Final answer:
Patients with kidney disease who take calcium and vitamin D supplements are at risk of hyperphosphatemia due to their kidneys' inability to excrete phosphate properly. This leads to vascular calcification, imbalances in calcium and phosphate levels, and could impact bone and cardiovascular health.
Step-by-step explanation:
Patients with kidney disease who take calcium and vitamin D supplements are at risk of hyperphosphatemia and potentially vascular calcification. This condition occurs because diseased kidneys cannot adequately excrete phosphate, which leads to elevated levels in the blood. High phosphate levels may cause a reciprocal drop in calcium levels (hypocalcemia), worsening when there's a deficiency in vitamin D3.
Additionally, kidney disease can impair the conversion of calcidiol into calcitriol, the active form of vitamin D needed for proper calcium and phosphate balance. These imbalances can contribute to weakened bones (osteomalacia), cardiovascular problems, and in children, a condition akin to rickets known as vitamin D resistant rickets.