More intensive treatment for patients with acute kidney injury did not bring better results in a large randomized, controlled clinical trial sponsored by the U.S. Department of Veterans Affairs and the National Institutes of Health.

The findings will be published Thursday in the New England Journal of Medicine; they were released early online.

The trial was conducted from 2003 to 2007 and included 1,124 critically ill adult patients at 17 VA hospitals and 10 university hospitals.

The study's lead author, Dr. Paul M. Palevsky, said the results may lead to a large savings in U.S. health care costs, estimated at $100 million to $250 million a year for this type of patient. He is chief of the renal section at the VA Pittsburgh Healthcare System and a professor of medicine at the University of Pittsburgh School of Medicine.

In acute kidney injury, the kidneys shut down, causing fluids and waste products to build up in the body. The VA reports the condition has a 50 percent to 80 percent death rate.

In the study, patients who did not need drugs to maintain blood pressure were assigned to either a six-day or three-day dialysis to filter toxins and extra fluid from the blood.

Those patients who needed drugs to increase blood pressure were assigned to two other forms of blood cleaning, both divided into intensive or less intensive groups.

Throughout the study, patients remained in intensive or less intensive therapy, although as their clinical conditions changed, they could change forms of therapy, Dr. Palevsky said.

There was no difference in death rates in both groups, and both also had similar rates of recovering kidney function and other organ failure.

In an accompanying editorial, Dr. Joseph V. Bonventre of Harvard Medical School wrote that he had concerns about the change of therapy offered to patients in the study.

"When a patient transitions from one therapy to another, the dialysis dose is unlikely to be equivalent," he said, adding that results could be affected by different methods in the high-intensity and low-intensity groups. "For example, there was a small over-representation of sustained low-efficiency dialysis in the intensive-therapy group."

Dr. Bonventre wrote that the study had "a predominance of male patients," so there is a question of whether its results can be applied to female patients. And, he said, the results cannot be simply applied to patients with chronic kidney disease, who then have acute kidney injury, since the study excluded any patients with advanced chronic kidney disease.

He concluded, "Given the results of the [Acute Renal Failure Trial Network] study, the renal and intensive care communities must now focus on other strategies to help this population of patients. ... We still have a long way to go in treating acute kidney injury."