Oct. 14 (HealthDay News) -- Dialysis may not be worth undertaking for many older Americans in nursing homes who suffer kidney failure in addition to other ailments, a study finds.

The research, published in the Oct. 15 issue of the New England Journal of Medicine, found that this intervention failed to lengthen or improve most patients' lives.

"The hope was that even if dialysis [artificial kidney treatment] doesn't extend life, it might improve quality of life," said study lead author Dr. Manjula Kurella Tamura, assistant professor of nephrology at Stanford University School of Medicine. "We wanted to look at whether this might be true."

But the study of more than 3,700 nursing home residents found that few were better able to perform activities of daily living, such as eating, dressing and using the bathroom, following dialysis, and many actually suffered declines in those areas.

Indeed, only one of every eight of the people in the study was able to maintain pre-dialysis functional capacity, Kurella Tamura said.

In the 12 months after starting dialysis, 58 percent of the participants died.

Americans over the age of 80 are the fastest-growing segment of the 400,000-strong U.S. dialysis population, and at least a third of them have other chronic illnesses, such as heart disease or diabetes, she said.

"In these types of patients, kidney failure often occurs in the context of other serious conditions," Kurella Tamura noted. "The failure to show improvement may be a manifestation of these other conditions."

And dialysis itself can tax weak, elderly people, she added. "They have to travel to treatment centers, and treatment can take three to four hours three times a week," Kurella Tamura said. "That takes a lot of time and can be cumbersome. It also takes away time when patients might be in programs to improve functional capacity."

The study results can help both doctors and older nursing home patients make educated decisions about dialysis, she said. "These results will be surprising even for doctors who care for dialysis patients on a daily basis," Kurella Tamura said. "They can lead to more informed discussions with patients about the expected prognosis and options for palliative care. They can help patients make informed decisions about treatment options."

Even now, one-fourth to one-third of such elderly people who opt for dialysis choose to end it, she said.

The findings help build a case for appropriate expectations, another expert said.

"There has been some earlier work that suggested that the course of frail elderly people was not very promising when they started dialysis," said Dr. Peter Aronson, professor in the nephrology section at Yale School of Medicine, who was familiar with the study. "This is the first to look at the subject in detail and document what happens when they start dialysis."

A weakness of the study was that it did not have a control group of elderly nursing home residents with a similar degree of kidney failure who did not receive dialysis, Aronson said. But there are obvious reasons why such a controlled study would be difficult to conduct, he said.

The study "does not make the case that if you are old, you shouldn't have dialysis," Aronson said. "And it should not be turned into an argument that we should ration dialysis, but it is important to have realistic expectations about whether dialysis will help you get better."

The issue of medical care for such old, frail people is "very difficult, both medically and ethically," Aronson said. "We should not ration it or withhold it from anybody, but it is important for doctors and patients to have realistic expectations about what to expect and to have appropriate discussions about end-of-life care."

SOURCES: Manjula Kurella Tamura, M.D., assistant professor, nephrology, Stanford University School of Medicine, Stanford, Calif; Peter Aronson, M.D., C.N.H. Long professor of internal medicine, professor of cellular and molecular physiology, section of nephrology, Yale School of Medicine, New Haven, Conn; Oct. 15, 2009 New England Journal of Medicine