Abstract
BACKGROUND Hyperphosphataemia in patients with chronic kidney disease (CKD) is associated with mineral and bone disorder and increased cardiovascular mortality. Despite phosphate binders (PB), nutrition counselling and dialysis therapy, the prevalence of hyperphosphataemia remains unacceptably high. It was hypothesized that an inadequate relation of PB dose to meal inorganic phosphorus (iP) content may be an important factor for failure of phosphate management. METHODS The innovative 'Phosphate Education Program' (PEP) bases on patient empowerment to eye-estimate meal iP content by newly defined 'Phosphate Units' (PU; 1 PU per 100 mg phosphorus) and self-adjust PB dosage to dietary iP intake by an individually prescribed PB/PU ratio (PB pills per PU). In a prospective study, 16 children (aged 4-17 years) with CKD and their parents were trained with the PEP concept and followed up for 24 weeks for changes in serum electrolyte levels, dietary behaviour and PB dose. RESULTS Within 6 weeks after PEP training, the percentage of children with serum phosphate (PO) >1.78 mmol/l dropped from 63% (10/16) to 31% (5/16). Mean serum PO level decreased from 1.94 ± 0.23 at baseline to 1.68 ± 0.30 (SD) mmol/l in Week 7-12 (P = 0.02) and to 1.78 ± 0.36 (SD) mmol/l in Week 19-24 (P = 0.2), whereas serum calcium [2.66 ± 0.3 vs 2.60 ± 0.23 (SD) mmol/l in Weeks 7-12 (P = 0.45) and 2.66 ± 0.23 (SD) mmol/l in Week 19-24 (P = 0.21)] and serum potassium [4.69 ± 0.48 vs 4.58 ± 0.68 (SD) mmol/l in Week 7-12 (P = 0.40) and 4.65 ± 0.49 (SD) mmol/l in Week 19-24 (P = 0.73)] remained unchanged. The mean daily PB dose rose from 6.3 ± 2.9 to 8.2 ± 5.4 (SD) pills during observation period with an increased meal-to-meal variability (P = 0.04). Dietary iP intake was not affected by PEP concept. CONCLUSION The empowerment of children with CKD and their parents to self-adjust PB dose to eye-estimated meal iP content significantly improved management of hyperphosphataemia without reducing dietary iP intake.
