High Ultrafiltration Rate and Mortality among Patients Undergoing Hemodiafiltration at St. Luke's Medical Center-Global City: A Retrospective Cohort Study

Background: Effective hemodiafiltration (HDF) and volume clearance over shorter treatment times were made possible by the development of hydrostatic ultrafiltration and other technical advancements. Ultrafiltration is commonly used to treat fluid overload; however, it is uncertain if its rate influences outcomes. The study therefore aims to determine the association between high UFR and mortality; and the predictors of mortality in end-stage renal failure patients receiving hemodiafiltration. Methods: This was a retrospective analytical cohort study of the medical data of all patients >18 years old undergoing maintenance hemodiafiltration at the St. Luke’s Medical Center-Global City from January 2018 to December 2022. Records review was done to gather data on clinical and demographic variables, laboratory findings, UFR values, and mortality. Results: A total of 296 patients were included in the study and 93 (31.4%) were observed to have high UFR. The mean age was significantly higher among those without high UFR (67.3 years) than those with high UFR (61.4 years) (p-value = 0.002). Among those with high UFR, the mortality rate was 34.4% with median follow-up time of 4 years. Among those without high UFR, the mortality rate was 27.6% with median follow-up time of 4 years. High UFR was not seen to be significantly associated with mortality (HR=1.3, 95%CI=0.7 to 2.4, p-value = 0.443). Increasing age was significantly associated with higher risk for mortality (HR=1.03, 95% CI=1.02 to 1.05, p-value <0.0001). Conclusion: High UFR was not associated with increased risk of mortality in end-stage renal failure patients receiving hemodiafiltration. Only increasing age significantly predicts risk for mortality in this group of patients. Future prospective studies conducted in multiple centers are needed to validate the findings of the current study.