THOUGH Social Security's fiscal direction has taken center stage in Washington of late, Medicare's future financing problems are likely to be much worse. President Bush has asserted that the Medicare Modernization Act, which he signed in 2003, would solve some of those problems - "the logic is irrefutable," he said two months ago. Yet the Congressional Budget Office expects the law to create just $28 billion in savings during the decade after its passage, while its prescription drug benefit will add more than $400 billion in costs.

So, how can Medicare's ballooning costs be contained? One idea is to let people die earlier.

For the last few decades, the share of Medicare costs incurred by patients in their last year of life has stayed at about 28 percent, said Dr. Gail R. Wilensky, a senior fellow at Project HOPE who previously ran Medicare and Medicaid. Thus end-of-life care hasn't contributed unduly of late to Medicare's problems. But that doesn't mean it shouldn't be part of the solution. "If you take the assumption that you want to go where the money is, it's a reasonable place to look," Dr. Wilensky said.

End-of-life care may also be a useful focus because, in some cases, efforts to prolong life may end up only prolonging suffering. In such cases, reducing pain may be a better use of resources than heroic attempts to save lives.

The question becomes, how can you identify end-of-life care, especially the kind that's likely to be of little value? "It's very difficult to predict exactly when a given individual is going to die, in most cases," said David O. Meltzer, an associate professor of medicine at the University of Chicago who also teaches economics. "But there's no question that there are many markers we have of someone who is approaching the end of life."

Even with that knowledge, however, Dr. Meltzer warned against putting the brakes on care just as a patient takes an inexorable turn for the worse. Studies of doctors who intervened at that point to stave off unproductive care have found little success in cutting costs, he said. Instead, he recommended that doctors try to prepare patients and families for less resource-intensive care at the end of life. "There is no question, as a clinician, and as a patient and the family members of patients, there are things you can do to make sure that expenditures with little chance of being helpful won't be undertaken," he said. "You explain to people that the goal of medical care is not always to make people live longer."

Explaining that principle early on could make a difference in the cases that appear to pose the biggest problem: those in which the patient's health changes suddenly and severely. Dr. Wilensky cited recent research showing that these cases incurred high costs with scant medical benefit.

"When someone starts going south, and there was not an expectation that that was going to happen, you probably pull out all the stops," she said.

These choices can actually harm patients, contradicting the purpose of the treatment, said Dr. Arnold S. Relman, a professor emeritus of medicine and social medicine at Harvard and former editor in chief of The New England Journal of Medicine. "Sometimes, you know that death is inevitable over the next few weeks or few months," he said. "And then there are some doctors, and some families, who just don't want to confront that, and feel that they want to and should invest everything possible - the maximum amount of resources - in fighting the inevitable. That often results in prolonging the pain and discomfort of dying."

Dr. Wilensky said these cases often involved an unusual number of specialists and other doctors visiting the patient, as well as a potentially excessive number of tests. Better coordination of care within hospitals and with other providers could curtail these extra efforts, she said. She also suggested that more use of evidence-based medicine, in which care is guided by documented cases and statistics, could discourage doctors from pursuing treatments with little chance of success.

Yet teaching doctors and patients to say no could be a losing battle. "It doesn't fit human nature, and it certainly doesn't fit our culture," Dr. Relman said. "Most Americans - and most people who are educated in advanced societies now - believe that each person is entitled to, technically and scientifically, the best medical care that they can get."

Introducing gatekeepers, the administrators in health maintenance organizations who choose which procedures patients may undergo, could take the often-emotional decisions about end-of-life care out of doctors' and patients' hands. Indeed, incorporating more of these managed-care-style practices into Medicare is a primary emphasis for the Bush administration, along with greater competition among providers, said Bill Pierce, a spokesman for the Department of Health and Human Services.

But Dr. Relman predicted that the public wouldn't stand for it. "That's exactly why the traditional H.M.O., with the gatekeeper, has given way and is so unpopular and has been replaced by the P.P.O." or preferred provider organization, he said. In order to cut costs, he said, a complete revamping of Medicare's payment system is needed - especially for outpatient care that the government buys on a fee-for-service basis.

AN alternative to saying no would be to encourage severely ill patients to choose hospice care, where the emphasis in treatment shifts from cure to quality of life. Patients are made to feel as comfortable as possible, and reducing pain takes precedence over radical procedures. At present, only about 1.6 percent of Medicare benefits pay for hospice care.

Despite the less-intensive brand of treatment, hospice care may not be cheaper than hospital care. "The assessment of hospice has not indicated that it's a clear money-saver," Dr. Wilensky said. "It can be, but we don't have very good examples."

And that lack of information should be the main target, said Dr. Meltzer, of the University of Chicago. "We just woefully underinvest in health-related research," he said. "The Medicare program has really very, very little money to fund research to help improve itself."

He added that the savings from changing doctors' and patients' expectations about end-of-life care could be substantial. Gauging just how substantial, he said, was the most important first step: "Research that helps us better to understand that is going to have an absolutely immense return."