Glomerular filtration rate (eGFR) is a test that describes the flow rate of fluid going through the kidneys and is associated with early dialysis initiation. Current guidelines in the United States place more emphasis on eGFR dialysis timing, according to the study. In addition, analysis of dialysis registries in the United States and Europe indicates that patients are starting dialysis earlier.
This study looked at data on 25,910 adult patients in Canada who started dialysis between 2001 and 2007. The researchers looked at the timing (early vs. late) and the risk of death in these two groups over time.
In the years studied, the mean estimated glomerular filtration rate at initiation of dialysis increased from 9.3 to 10.2,and the proportion of early starts rose from 28% percent, according to the study. In addition, mean glomerular filtration rate was 15.5 mL/min per 1.73 m² among those with early initiation and 7.1 mL/min per 1.73 m2 among those with late initiation.
The unadjusted hazard ratio (HR) for mortality with early relative to late initiation was 1.48, according to the study. The HR decreased to 1.18 after adjustment for certain patient factors.
The mortality differential between early and late initiation per 1,000 patient-years narrowed after one year of follow-up, but never crossed and began widening again after 24 months of follow-up, the authors write. The differences were significant at 6, 12, 30 and 36 months.
The authors concluded that further research into detecting the signs, symptoms and laboratory test results associated with a higher death rate and worsened quality of life in patients with kidney failure is needed.
"The consistent absence of a survival benefit with early initiation of dialysis across a variety of study designs, populations and health care delivery systems supports the conclusion that early initiation confers no survival benefit, and argues against pre-emptive initiation of dialysis in asymptomatic patients," wrote Dr. William Clark, Nephrologist at London Health Sciences Centre and Scientist at Lawson Health Research Institute with coauthors. "In contrast to early initiation of dialysis, early referral to a nephrologist is consistently associated with better survival."
