More Intensive Dialysis Does Not Improve
Outcomes among Patients with Acute Kidney Injury
No significant difference in death rates or other outcomes was
found between a group of patients with acute kidney injury that
received intensive dialysis and another group that received a more
standard regimen of dialysis, according to a joint Department of
Veterans Affairs (VA) and National Institutes of Health (NIH) study
published in the June issue of the New England Journal of Medicine. Acute
kidney injury, also called acute renal failure, is a common complication
in hospitalized patients that is associated with very high mortality
rates. In-hospital mortality rates of critically-ill patients typically
range from 50 percent to 80 percent.
Several prior single-center studies in patients with acute kidney
injury had suggested improved survival with more intensive dialysis,
which is significantly more costly to administer. "We now
have definitive evidence that intensive treatment of acute kidney
injury is no more beneficial in improving treatment outcomes than
the usual level of care," said NIH Director Elias A. Zerhouni,
M.D. "As a result, the findings of this well-designed study
may help prevent unnecessary medical expenditures."
Within 60 days after starting dialysis, 302 patients (53.6 percent)
in the intensive treatment group died compared to 289 patients
(51.5 percent) in the less-intensive treatment group. Also, the
study reports no significant differences between the two groups
in recovery of kidney function, the rate of failure of organs other
than kidneys, or the number of patients able to return to their
prior living situations.
No medications have been found to be effective in treating acute
kidney injury, so doctors use hemodialysis and other forms of renal-replacement
therapy to support patients whose kidneys do not function properly.
Hemodialysis uses a machine to clean waste and extra fluid from
the blood when the kidneys can’t do the job.
In this study, doctors provided renal-replacement therapy to both
patient groups. Patients who did not require medications to maintain
their blood pressure were treated with conventional dialysis, either
three times per week in the less-intensive arm of the study or
six times per week in the intensive arm. Patients who were unstable
and required medications to increase their blood pressure were
treated with more gentle forms of dialysis, either a slower form
of hemodialysis called SLED or a continuous form at a lower or
higher dose as randomly assigned. Patients were able to switch
between forms of therapy as their clinical condition changed, while
remaining within the lower or higher intensity treatment arms of
"The main purpose of this study was to see if intensive therapy
would reduce the death rate, shorten the duration of the illness,
and decrease the number of new complications in other organs among
patients with acute kidney injury," said co-author Robert
A. Star, M.D., director of NIDDK’s Division of Kidney, Urologic
and Hematologic Diseases. "Though this was found not to be
the case, it is important that we know this so we can focus future
research on finding more beneficial treatment strategies."
"Unlike earlier studies that used only a single method of
therapy, our use of an integrated strategy of continuous and intermittent
methods of therapy allows us to apply these study results more
readily to clinical practice," explained study chair Paul
M. Palevsky, M.D., chief of the Renal Section at the VA Pittsburgh
Healthcare System and a professor of medicine at the University
of Pittsburgh School of Medicine. "What is important about
these results is that they outline the limits of effective therapy."
The VA/NIH Acute Renal Failure Trial Network study, cosponsored
by the VA’s Cooperative Studies Program (CSP) and NIH’s National
Institute of Diabetes and Digestive and Kidney Diseases (NIDDK),
enrolled 1,124 critically-ill patients from 17 Veterans Affairs
medical centers and 10 university-affiliated medical centers across
the United States. The study was conducted from November 2003 through
The Cooperative Studies Program is a division of the U.S. Department
of Veterans Affairs Office of Research and Development. The CSP’s
mission is to advance the health and care of veterans through collaborative,
multi-center research studies that produce innovative and effective
solutions to national healthcare problems. More information about
CSP can be found at its website: http://www.csp.research.va.gov.
The National Institute of Diabetes and Digestive and Kidney Diseases,
a component of the NIH, conducts and supports research in diabetes
and other endocrine and metabolic diseases; digestive diseases,
nutrition, and obesity; and kidney, urologic, and hematologic diseases.
Spanning the full spectrum of medicine and afflicting people of
all ages and ethnic groups, these diseases encompass some of the
most common, severe, and disabling conditions affecting Americans.
For more information about NIDDK and its programs, see www.niddk.nih.gov.
The National Institutes of Health (NIH) — The Nation's
Medical Research Agency — includes 27 Institutes and
Centers and is a component of the U.S. Department of Health and
Human Services. It is the primary federal agency for conducting
and supporting basic, clinical and translational medical research,
and it investigates the causes, treatments, and cures for both
common and rare diseases. For more information about NIH and
its programs, visit www.nih.gov.