Calculating Dietary Phosphorus Reduction for CKD

A nurse is caring for a patient with chronic kidney disease (CKD) who is presenting with hyperphosphatemia. The patient’s current serum phosphate level is 7.0 mg/dL, whereas the normal range is typically between 2.5-4.5 mg/dL. To effectively manage the patient’s electrolyte balance, the nurse anticipates needing to administer phosphate binders and also monitor for potential complications related to high phosphate levels. If the patient's dietary phosphorus restriction is not adhered to, the risk for additional complications such as secondary hyperparathyroidism may increase. In this context, the nurse is required to calculate the necessary dietary phosphorus restriction if the nephrologist recommends a target intake of 800 mg/day. However, the current intake is unknown. Assuming the patient typically ingests a phosphorus-rich diet leading to a daily intake of 2000 mg/day, calculate the percent reduction needed to achieve the target intake.