Washington ? In a report with major political ramifications, Medicare trustees said Tuesday that soaring medical costs and a new prescription drug law will drive the health-care system for America’s elderly into insolvency in only 15 years.

Medicare’s board of trustees, including three Cabinet officers, said the system will be unable to pay all of its bills by 2019, seven years earlier than the board had predicted a year ago, and urged Congress to act quickly to deal with the problem.

They said expenditures for Medicare would exceed payroll tax income this year, starting a drain on the Medicare trust fund that will mushroom when the Baby Boom generation begins to retire early in the next decade — and cause it to run dry in a decade and a half.

The trust fund up to now has been generating surpluses from payroll taxes on employees. More than 41 million Americans are on Medicare. By 2020, this number is expected to exceed 61 million.

The trustees presented a grim long-term outlook for Medicare, saying that spending for the program would surpass that for Social Security by 2024. In 2078, their report said, Medicare costs would be nearly double of those for Social Security.

“Growth of this magnitude, if realized, would place a substantially greater strain on the nation’s workers, Medicare beneficiaries and the federal budget,” they said.

At the same time, trustees for the Social Security system said trust funds for the retirement program for the elderly would be exhausted by 2042 — the same date projected in last year’s report. Treasury Secretary John Snow, meanwhile, on Tuesday called on Congress to establish private personal retirement savings accounts to supplement the system.

Health and Human Services Secretary Tommy Thompson, one of the Medicare trustees, said he believed cost-savings provisions included in the prescription drug law passed last year would improve Medicare’s financial picture beyond what the report projected. These include incentives for preventive medicine and cost-containment measures, he said.

Sen. John Kerry of Massachusetts, the presumed Democratic nominee for president, criticized President Bush’s “irresponsible tax cuts for the wealthy and his giveaway to the prescription drug companies,” adding that because of these actions, Medicare “might not even be there for our generation.”

Signaling that Medicare will be a major issue in the campaign, Kerry added that “unless we make a change, if you are 50 years old or younger, Medicare will be broke by the time you reach retirement.”

Trustees make a report every year on the financial health of Social Security and Medicare trust funds, but an election-year report always carries more weight with the public. The 2019 date for Medicare insolvency covers only the hospital fund, not Part B medical coverage for which senior citizens pay part of the cost with monthly premiums.

At the White House, spokesman Trent Duffy said escalating health-care costs are chiefly responsible for the projection that Medicare would be insolvent seven years sooner than previously projected. “It’s health-care costs, over 70 percent — not prescription drugs,” he said.

At a news conference, Thompson held out the hope that Medicare’s financial health would not be as dire as predicted. He said he expected savings from introducing more privatization into Medicare, luring more seniors into private health-care plans.