Radiologists use expensive contrast agents less frequently if their expenditures are watched by hospital administrators.
If administrators don't urge radiologists to control costs, their use of low-osmolality agents is likely to grow, even though they know that these agents cost about 20 times more than other agents while offering little additional benefits to many patients, said researchers from the Rand Corp. and the University of California-Davis Medical Center.
The use of low-osmolality agents exemplifies the troubles that lie ahead for healthcare administrators. Increasingly, they are the ones who must force physicians to confront the question of whether the system can afford to pay high prices to gain only marginal medical benefits.
Limited Medicare payments and emerging forms of reimbursement, such as capitation, are fueling this trend. Under such reimbursement plans, providers have the responsibility of making the best use of limited resources (Feb. 28, p. 36).
"As medicine moves away from serving individual patients toward serving patient populations, the relationship between the physician and administrator is likely to change," said Peter Jacobson, a senior behavioral scientist at Santa Monica, Calif.-based Rand.
"I think many physicians understand the tradeoffs to be made," he continued. "But what happens is that they become patient advocates, and the administrator brings a viewpoint that weighs the tradeoffs systematically, consistent with quality of care at a reasonable cost."
Mr. Jacobson's conclusions are one result of a study of contrast-agent use that he's conducting with John Rosenquist, M.D., a UC-Davis radiology professor. The study is part of the Office of Technology Assessment's look at how so-called "defensive medicine" affects the spread of medical technology. The OTA report is expected out this summer. The researchers discussed some results of their study at the recent Radiological Society of North America meeting in Chicago.
Low-osmolality contrast agents, used in diagnostic imaging to produce clearer pictures, are at the center of a controversy that's almost 10 years old.
The agents don't trigger as many adverse reactions as high-osmolality agents because their osmolality-the concentration of particles dissolved in a solution-is closer to that of normal body fluids. Most low-osmolality agents also are nonionic, which probably makes patients less likely to vomit or feel nauseous than ionic agents.
Although there's evidence to prove that low-osmolality agents cause fewer reactions that can be classified as mild and moderate, there's less evidence that they cause fewer life-threatening reactions, researchers say.
Meanwhile, at one hospital, a low-osmolality agent cost about $46 for 50 milliliters in 1992, while its high-osmolality counterpart was priced at $2, Mr. Jacobson said. That price differential means that the universal use of low-osmolality agents would add about $1 billion to the nation's medical bill each year. In a small hospital, the cost of using low-osmolality agents for all patients, instead of selectively using high-osmolality agents, is $250,000 to $500,000 a year.
That's why the American College of Radiology as well as many insurers and providers recommend that radiologists use low-osmolality agents only for patients considered at high risk for negative reactions. Despite these recommendations, low-osmolality agents are used in more than 50% of procedures, up from about 15% of procedures after their introduction in 1986, Mr. Jacobson said. Current usage exceeds estimates of the percentage of people who are at high risk for reactions, he said.
Although radiologists know how the agents compare in cost, they use low-osmolality agents for low- and high-risk patients because they believe that low-osmolality agents will help their patients. Many argue that they're morally bound to use the agents if there's any chance that doing so will benefit their patients, Mr. Jacobson said.
Also, radiologists often aren't forced to judge between competing needs. Expenditures for contrast agents often come out of the hospital's budget, not the budget of the radiology department. Changing the part of the budget from which agent purchases come might lower the use of high-cost agents, the researchers said.
Today, several hospitals that once exclusively used low-osmolality agents are developing guidelines that limit their use. The guidelines are most effective if hospital administrators participate in their development and enforcement, Mr. Jacobson said, noting that, "In some cases, it's likely to require involvement at the top."