Klotho Gene Polymorphism in Dialyzed Patients With Hyperphosphatemia

Inclusion Criteria: Group 1 * Stable hemodialysis patients for at least 3 months * Phosphatemia \> 2.5 mM * Kt/V \> 1.2 * Total weekly phosphate removal \> 75 millimoles Group 2 * Stable hemodialysis patients for at least 3 months * Phosphatemia \< 1.5 mM * Kt/V \> 1.2 * Total weekly phosphate removal \> 25 millimoles Exclusion Criteria: * Age \> 80 years * Insufficient dialysis dose (Kt/V \< 1.2) * Total weekly phosphate removal \< 25 mM * Problems with vascular access for hemodialysis (central catheter, arteriovenous \[A-V\] fistula dysfunction) * Methods of dialysis different than the classical hemodialysis (peritoneal, hemofiltration, or hemodiafiltration with or without acetate) * Intolerance or allergy to ARYLANE M9 dialyzers * Hypocalcemia \< 2.0 mmol/liter * Hypophosphatemia \< 0.6 mmol/liter * Daily protein intake \< 0.6 g/kg/j * Parathyroidectomy at least 3 months prior to the study * Evolutive neoplasia with or without secondary lytic bone lesions * Intestinal malabsorption * Alcoholism * Corticotherapy * Treatment by bisphosphonates, fluor or recombinant PTH * Malnutrition (body mass index \[BMI\] \< 15) * Amputation of lower members (\> 10% of total body) * Prolonged immobilization * Secondary hyperparathyroidism (PTH \> 1400 pg/ml) * Vitamin D deficiency (25OHD3 \< 10 ng/ml)