Ultrafiltration rate adjusted to body weight and mortality in hemodialysis patients

Mortality among hemodialysis patients remains high. An elevated ultrafiltration rate adjusted by weight (UFR/W) has been associated with hypotension and higher risk of death and/or cardiovascular events. We evaluated the association between UFR/W and mortality in 215 hemodialysis patients. The mean follow-up was 28 ± 6.12 months. We collected patients’ baseline characteristics and mean UFR/W throughout the follow-up. Mean UFR/W was 9.0 ± 2,4 and tertiles 7.1 y 10.1 mL/kg/h. We divided our population according to the percentage of sessions with UFR/W above the limits described in the literature associated with increased mortality (10.0 ml/kg/h and 13.0 mL/kg/h). Patients with higher UFR/W were younger, with higher interdialytic weight gain and weight reduction percentage but lower dry, pre and post dialysis weight. Throughout the follow-up, 46 (21.4%) patients died, the majority over 70 years old, diabetic or with cardiovascular disease. There were neither differences regarding mortality between groups nor differences in UFR/W among patients who died and those who did not. Contrary to previous studies, we did not find an association between UFR/W and mortality, maybe due to a higher prevalence in the use of cardiovascular protection drugs and lower UFR/W. The highest UFR/W were observed in younger patients with lower weight and were not associated with an increased mortality. La mortalidad de los pacientes en hemodiálisis es alta. Una tasa de ultrafiltración horaria ajustada por peso (UFR/W) elevada se ha asociado a episodios de hipotensión arterial y mayor riesgo de muerte y/o eventos cardiovasculares. Hemos evaluado la asociación entre UFR/W y mortalidad en 215 pacientes en hemodiálisis prevalentes seguidos durante 28 ± 6,12 meses. Se estimaron características clínicas basales y UFR/W media a lo largo del seguimiento. La UFR/W media fue 9,0 ± 2,4 y los terciles 7,1 y 10,1 mL/kg/h. Se categorizó a la población en función del tiempo que habían estado con UFR/W igual o superior a los puntos de corte descritos en la literatura como asociados a mayor mortalidad (10,0 mL/kg/h y 13,0 mL/kg/h). Los pacientes con mayor UFR/W fueron más jóvenes, con mayor ganancia de peso interdiálisis y porcentaje de reducción de peso, pero con menor peso seco, inicial y final. Durante el seguimiento, fallecieron 46 (21,4%) pacientes de los cuales la mayoría eran >70 años, diabéticos o con enfermedad cardiovascular. No hubo diferencias en mortalidad entre los grupos de UFR/W ni di