Background: Phosphate (P) control is crucial to prevent secondary hyperparathyroidism and extraosseous calcification. Hemodialysis techniques normally used do not remove the amount of P absorbed from an adequate protein intake. Our long hemodialysis (LHD) procedure produces greater P removal in a seven-hour session than in a conventional four-hour session. Our aim was to assess the evolution of predialysis serum P and Ca x P product in patients on intermittent LHD during the first two years on this dialysis schedule.
Methods: Eight irregular compliant patients underwent LHD for 12 months; five of them completing 24 months. In the conventional hemodialysis (CHD) period, session time was 12 hours per week, while it was 21 hours per week in LHD. We compared P and Ca x P product throughout both periods; each patient was his or her own control.
Results: Mean serum P improved from 7.1 +/- 1.1 mg/dL in CHD to 5.6 +/- 1.1 mg/dL during the second year on LHD (P < 0.05). Mean Ca x P product decreased from 64 +/- 12.7 mg2/dL2 during CHD to 50.9 +/- 10.3 mg2/dL2 at the end of the second year of LHD.
Conclusion: By prolonging dialysis time to 21 hours per week, better P serum control and lower Ca x P product were achieved in our patients.