Rate of decline in residual kidney function pre and post peritoneal dialysis initiation: A post hoc analysis of the IDEAL study

PLoS One. 2020 Nov 16;15(11):e0242254. doi: 10.1371/journal.pone.0242254. eCollection 2020.

Abstract

Background: Residual kidney function (RKF) is associated with improved survival and quality of life in dialysis patients. Previous studies have suggested that initiation of peritoneal dialysis (PD) may slow RKF decline compared to the pre-dialysis period. We sought to evaluate the association between PD initiation and RKF decline in the Initiating Dialysis Early And Late (IDEAL) trial.

Methods: In this post hoc analysis of the IDEAL randomized controlled trial, PD participants were included if results from 24-hour urine collections had been recorded within 30 days of dialysis initiation, and at least one value pre- and one value post-dialysis commencement were available. The primary outcome was slope of RKF decline, calculated as mean of urinary creatinine and urea clearances. Secondary outcomes included slope of urine volume decline and time from PD initiation to anuria.

Results: The study included 151 participants (79 early start, 72 late start). The slope of RKF decline was slower after PD initiation (-2.69±0.18mL/min/1.73m2/yr) compared to before PD (-4.09±0.33mL/min/1.73m2/yr; change in slope +1.19 mL/min/1.73m2/yr, 95%CI 0.48-1.90, p<0.001). In contrast, urine volume decline was faster after PD commencement (-0.74±0.05 L/yr) compared to beforehand (-0.57±0.06L/yr; change in slope -0.18L/yr, 95%CI -0.34--0.01, p = 0.04). No differences were observed between the early- and late-start groups with respect to RKF decline, urine volume decline or time to anuria.

Conclusions: Initiation of PD was associated with a slower decline of RKF compared to the pre-dialysis period.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Anuria / etiology
  • Creatinine / urine
  • Disease Progression
  • Female
  • Glomerular Filtration Rate
  • Humans
  • Kidney / physiopathology*
  • Kidney Failure, Chronic / pathology
  • Male
  • Middle Aged
  • Peritoneal Dialysis*
  • Proportional Hazards Models
  • Urea / urine

Substances

  • Urea
  • Creatinine

Grants and funding

The IDEAL study was supported by grants from the National Health and Medical Research Council of Australia (211146 and 465095), the Australian Health Ministers Advisory Council (PDR 2001/10), the Royal Australasian College of Physicians/Australian and New Zealand Society of Nephrology (Don and Lorraine Jacquot Fellowship), the National Heart Foundation (Australia), and the National Heart Foundation (New Zealand), and by unrestricted grants from Baxter Healthcare, Health Funding Authority New Zealand (Te Mana Putea Hauora O Aotearoa), the International Society for Peritoneal Dialysis, Amgen Australia, and Janssen-Cilag. IE is supported by a fellowship grant from the Centre Hospitalier de l’Université de Montréal and the Fondation du CHUM. YC is supported by an Early career fellowship grant from the NHMRC. AV received grant support from the Jacquot Research Establishment Fellowship Award and the Princess Alexandra Research Foundation. MGW is supported by Diabetes Australian Research Trust Millennium Grant. DJ is supported by an Australian National Health and Medical Research Council Practitioner Fellowship. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.