Background: Longer and more frequent dialysis sessions have demonstrated excellent survival and clinical advantages, while online haemodiafiltration (OL-HDF) provides the most efficient form of dialysis treatment. The aim of this study was to evaluate the beneficial effects of a longer (nocturnal) and more frequent (every-other-day) dialysis schedule with OL-HDF at the same or the highest convective volume.
Methods: This prospective, in-centre crossover study was carried out in 26 patients, 18 males and 8 females, 49.2±14 years old, on 4-5 h thrice-weekly post-dilution OL-HDF, switched to nocturnal every-other-day OL-HDF. Patient inclusion criteria consisted of stable patients with good vascular access and with good prospects for improved occupational, psychological and social rehabilitation. Patients were randomly assigned into two groups: Group A received the same convective volume as previously for 6 months followed by a higher convective volume for a further 6 months, while Group B received the same schedule in reverse order.
Results: Nocturnal every-other-day OL-HDF was well tolerated and 56% of patients who were working during the baseline period continued to work throughout the study with practically no absenteeism. The convective volume was 26.7±2 L at baseline, 27.5±2 with the unchanged volume and 42.9±4 L with the higher volume. eKt/V increased from 1.75±0.4 to 3.37±0.9. Bicarbonate, blood urea nitrogen (BUN) and creatinine values decreased, while phosphate levels fell markedly with a 90% reduction in phosphate binders. Blood pressure and left ventricular hypertrophy (LVH) improved and the use of anti-hypertensive drugs decreased. In both groups, BUN, creatinine and β2-microglobulin reduction ratios improved. Different removal patterns were observed for myoglobin, prolactin and α1-acid glycoprotein.
Conclusions: Nocturnal every-other-day OL-HDF could be an excellent therapeutic alternative since good tolerance and occupational rehabilitation, marked improvement in dialysis dose, nutritional status, LVH, phosphate and hypertension control and a substantial reduction in drug requirements were observed. In this crossover study, different removal patterns of large solutes were identified.