Daily dialysis reduces pulse wave velocity in chronic haemodialysis patients

Introduction. We have already demonstrated that in chronic HD patients the cyclic variations in both hydration status and blood pressure are responsible for changes in Pulse Wave Velocity (PWV); and that the cyclic variation of PWV influences mortality in dialysis patients. The aim of this study is to verify if is possible reduce the PWV modifying the three time a week dialysis to daily dialysis. Material and Methods. This is a controlled, randomized, cross-over study. We studied 60 oligo-anuric (urinary output <200 mL/day) patients on chronic standard bicarbonate HD for at least 6 months. They performed three HD sessions of four hours per week. Patients were classified into three groups: normal PWV before and after dialysis (LL); high PWV before and normal PWV after dialysis (HL); high PWV before and after dialysis (HH). The patients were randomised to three time a week dialysis; and daily dialysis for one month, changing dialysis schedule during second month. Results. 20 patients showed PWV-LL; 20 patients PWV-HL, and 20 patients PWVHH. The 3 groups of patients are homogeneous for sex, age, dialytic age and blood pressure. 2 patients of PWV-HH shift to PWV-HL group, while 90% of PWV-HL patients shift to normal values. Conclusions. We evidence for the first time that daily dialysis reduces PWV in dialysis subjects; and this issue can determine differences in mortality.