June 2, 2008

Intensive Dialysis No Better Than Standard for Acute Kidney Injury

Photo of two patients on dialysis

Researchers found no significant difference in death rates or other outcomes between patients with acute kidney injury that received intensive dialysis or those who received a more standard regimen of dialysis.

Acute kidney injury, also called acute renal failure, is a common complication in hospitalized patients. It's associated with very high mortality rates; in-hospital mortality rates of critically-ill patients typically range from 50-80%. No effective medications have been found to treat acute kidney injury, so doctors use hemodialysis and other forms of renal-replacement therapy to support patients whose kidneys don't function properly. Hemodialysis uses a machine to clean waste and extra fluid from the blood when the kidneys can’t do the job.

Smaller studies in the past had suggested that intensive dialysis, which is significantly more costly to administer than standard care, improves survival in patients with acute kidney injury. The Acute Renal Failure Trial Network study set out to see if intensive therapy could reduce the death rate, shorten the duration of illness and decrease the number of new complications in other organs among patients with acute kidney injury. The study was cosponsored by the Department of Veterans Affairs and NIH’s National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK).

The researchers enrolled 1,124 critically-ill patients from 17 Veterans Affairs medical centers and 10 university-affiliated medical centers across the United States. The patients were divided into 2 groups and given either a standard regimen of dialysis or a more intensive one. For patients with stable blood pressure, that meant renal-replacement therapy either 3 times per week in the less-intensive arm of the study or 6 times per week in the intensive arm. There were variations in treatment depending on the patient’s situation. For example, those who were unstable and required medications to increase their blood pressure needed more gentle forms of dialysis. Patients were also able to switch between forms of therapy as their clinical condition changed. However, the patients received lower or higher intensity treatments depending on which arm of the study they were originally assigned to.

The researchers reported in the June issue of the New England Journal of Medicine that within 60 days after starting dialysis, 53.6% of the patients in the intensive treatment group had died, compared to a similar 51.5% in the less-intensive treatment group. There were no significant differences between the 2 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.

“What is important about these results is that they outline the limits of effective therapy,” explained study chair Dr. Paul M. Palevsky, chief of the Renal Section at the VA Pittsburgh Healthcare System and a professor of medicine at the University of Pittsburgh School of Medicine.

The finding that intensive treatment of acute kidney injury is no more beneficial than the usual level of care may help to prevent unnecessary medical expenditures.

Related Links