The effect of diet education on the laboratory values and knowledge of hemodialysis patients with hyperphosphatemia

Objective: The purpose of this study was to evaluate the effectiveness of 20 to 30 minutes per month of additional diet education on monthly laboratory values (phosphorus, calcium, parathyroid hormone, and calcium/ phosphorus product) and knowledge of dietary phosphorus management in hemodialysis patients with hyperphosphatemia. Design: A quasi-experimental design. Setting: Three outpatient dialysis centers owned by the same corporation in 1 southern state. Patients: Based on a 3-month average serum phosphorus >6.0 mg/dL, 70 patients were selected for participation; 63 dialysis patients completed the study, 32 in the experimental group and 31 in the control group. Intervention: All patients completed a before-and-after knowledge test and had monthly blood samples drawn. Each month, the same registered dietitian provided the routine laboratory results review with control group. The experimental group received the routine laboratory review plus, 20 to 30 minutes of additional diet education specifically targeting phosphorus. Main Outcome Measures: Before-and-after knowledge test results and baseline and final serum calcium, phosphorus, parathyroid hormone, and calcium/phosphorus product levels. Results: At baseline, there were no significant differences in any of the laboratory values, but the knowledge level of the experimental group was greater (P < .05) After 6 months, gains in knowledge were significantly higher in the intervention group, and the serum phosphorus and calcium/phosphorus product levels were significantly lower (P < .01) than in the control group. Conclusion: Based on this research, those patients who received extra education monthly showed positive changes, which may be beneficial in reducing hyperphosphatemia. (C) 2004 by the National Kidney Foundation, Inc.