Dietary Protein Source and Phosphate Levels in Patients on Hemodialysis

Objective: To determine the sources of protein and phosphorus levels from the food consumed by patients on dialysis.

Design and methods: This is a retrospective, secondary data analysis of the Comprehensive Dialysis Survey study participants who had a baseline food frequency questionnaire and baseline lab data (N = 358). We examined intake of protein, phosphorus, and 7 other key nutrients from a subcohort of the Comprehensive Dialysis Survey based on the published National Kidney Foundation Kidney Dialysis Outcome Quality Initiative's nutrition recommendations. We studied the relationship of dietary protein source (plant or animal) with phosphorus intake using self-reported data from food frequency questionnaires. Variables included in final analysis are demographic, lab variables (albumin and prealbumin, alpha-1 acid glycoprotein, and C-reactive protein), and nutrition variables (calorie density, protein density, total fat, saturated fat, cholesterol, carbohydrates, phosphorus, calcium, sodium, potassium, plant-based protein, animal-based protein, and daily protein intake).

Results: Most of the patients had a lower than recommended consumption of calories, protein, phosphorus, and potassium while sodium, total, and saturated fats were overconsumed. Patients intake of dietary protein and calories was proportional to the amount of food consumed for both plant- and animal-based food. The levels of dietary protein and phosphorus were significantly (P < .05) lower in patients who primarily consumed a plant-based diet than in those who mainly consumed an animal-based diet.

Conclusions: Consuming more plant-based protein as part of a varied diet could be nutritionally adequate while limiting intake of absorbable dietary phosphorus. More research in plant-based protein diets and their impact on patients with end-stage renal disease is needed.