Nutrient intake assessed with Diet History Questionnaire II, in relation to long-term calcium-phosphate control in hemodialysis patients with end-stage renal failure

Abstract

Background: Diet is a key factor that determines proper alignment of calcium-phosphate and nutritional status among hemodialysis (HD) patients.

Objectives: To assess the nutrient intake in relation to long-term calcium-phosphate control in HD patients with end-stage renal failure.

Material and methods: The study included 107 patients (66 men, 41 women) from 10 dialysis centers in the Upper Silesia region of Poland. To analyze the diet composition during the previous year, a portion-sized version of the Diet History Questionnaire II (DHQ-II) from National Institutes of Health was used. The nutrient intake was assessed in accordance with the most complex recommendations on HD patients' nutrition - K/DOQI Clinical Practice Guidelines for nutrition in chronic renal failure. Poor long-term alignment of calcium-phosphate homeostasis was defined as the presence of over 50% monthly phosphorus concentrations exceeding 5 mg/dL, and for calcium 10.2 mg/dL, during the last 6-month period.

Results: Lower than recommended protein intake was found in 63% of HD patients (average consumption: 0.9 ±0.5 g/kg/day). Most of the patients consumed too much fat (33.5 ±6.7% of daily energy intake) and sodium (2912 ±1542 mg/day). In 42% of patients, dietary phosphorus intake was consistent with the recommendations (13.3 ±7.5 mg/kg/day). Protein intake over 1.2 g/kg/day resulted in an increased consumption of phosphorous, but did not increase the risk of misalignment of phosphorus concentrations (OR = 1.15 [0.40-3.27]); p = 0.8). Poor control of serum phosphorus concentrations was observed in 69% of patients (they were on average 8 years younger). The average intake of protein and phosphate in the groups with good or not satisfactory serum phosphorus alignment did not differ significantly.

Conclusions: Adequate control of protein intake is not sufficient to obtain phosphorus alignment, especially in younger HD patients.

Keywords: calcium-phosphate control; diet; food frequency questionnaire; hemodialysis; nutrient intake.