Clinical question: What is the ideal estimated glomerular filtration rate (eGFR) at which to start dialysis in patients with advanced chronic kidney disease?
Background: Uncertainty exists over the optimum time to start dialysis in order to lower mortality and cardiovascular events. The Initiating Dialysis Early and Late (IDEAL) trial, published in 2010, demonstrated that initiating dialysis at an eGFR of 10 to 14 mL/min/1.73 m2 was not associated with an improvement in survival or clinical outcomes as compared to patients with the eGFR 5 to 7 mL/min/1.73 m2.
Study design: A nationwide observational cohort study
Setting: National Swedish Renal Registry of patients referred to nephrologists
Synopsis: From 2007 to 2017, 10,290 patients were included in this study; an eGFR between 6 and 7 mL/min/1.73 m2 was used as the reference group, and 15 dialysis initiation techniques with eGFR values ranging from 4 to 19 mL/min/1.73 m2 in increments of 1 mL/min/1.73 m2 were evaluated.
Early initiation of dialysis (eGFR 15–16 mL/min/1.73 m2) was associated with a 5.1% (95% CI 2.5%–6.9%) lower absolute risk of mortality after five years as compared to eGFR 6-7 mL/min/1.73 m2. Additionally, an early start was linked to a 3.3% lower absolute risk of major adverse cardiovascular events. For 1.6 months longer survival advantage, dialysis must be started on average four years earlier.
Rather than supporting a strategy of early initiation, the authors conclude the modest survival benefit may not outweigh the substantially longer period spent on dialysis.
Bottom line: Early initiation of dialysis increases survival by 1.6 months and modestly decreases cardiovascular events. However, to achieve maximum survival benefits, one would need to initiate dialysis four years earlier.
Dr. Sheikh
Citation: Fu EL, et al. Timing of dialysis initiation to reduce mortality and cardiovascular events in advanced chronic kidney disease: nationwide cohort study. BMJ. 2021;375:e066306. doi: 10.1136/bmj-2021-066306.
Dr. Sheikh is associate program director for the department of internal medicine and assistant professor of medicine at the University of New Mexico Hospital, Albuquerque, N.M.