Proportion of Hemodialysis treatments with High Ultrafiltration Rate and the association with Mortality

Abstract

Background: Rapid fluid removal during hemodialysis has been associated with increased mortality. The limit of ultrafiltration rate (UFR) monitored by the Centers for Medicare and Medicaid Services is 13 ml/kg/hr. It is not clear if the proportion of treatments with high UFR is associated with higher mortality. We examined the association of proportion of dialysis treatments with high UFR and mortality in end stage kidney failure patients receiving hemodialysis Methods: retrospective study of incident patients initiating hemodialysis between January 1, 2010 to December 31, 2019 at Emory dialysis centers. The proportion of treatments with high UFR (>13ml/kg/hr) per patient was calculated using data from the initial 3 months of dialysis therapy. Patients were categorized based on quartiles of proportion of dialysis sessions with high UFR. Risk of death and survival probabilities were calculated and compared for all quartiles. Results: Of 1050 patients eligible, the median age was 59 years, 56% were male and 91% were black. The median UFR was 6.5 ml/kg/hr and the proportion of sessions with high UFR was 5%. 31% of patients never experienced high UFR. Male gender, younger age, shorter duration of hemodialysis sessions, lower weight, diabetic status, higher albumin and history of heart failure were associated with higher proportion of sessions with high UFR. Patients in the higher quartile (26% dialysis with high UFR, average UFR 9.8ml/kg/hr, median survival of 5.6 years) had a higher risk of death (adjusted hazard-ratio 1.54, CI: 1.13-2.10) compared to those in the lower quartile (0% dialysis with high UFR, average UFR 4.7ml/kg/hr, median survival 8.8 years). Conclusions: Hemodialysis patients that did not experience frequent episodes of elevated UFR during the first three months of their dialysis tenure had a significantly lower risk of death compared to patients with frequent episodes of high UFR.