Wednesday, October 15, 2008

At least 10% of the increase in Medicare expenditures since the mid-1990s is due to increased rates of one type of elective surgery, according to a recent study, and many of the patients may not need it. University of California, San Francisco found that only 44% of patients who undergo an elective cardiac surgery called angioplasty get the recommended test to determine whether the procedure is appropriate.

As a result, patients may be receiving a procedure that they either do not need or for which the risk outweighs the benefit. The operation opens partially clogged arteries in patients with heart disease and the annual rate of elective angioplasties has tripled in the United States during the last decade.

Angioplasties are currently being performed at a rate of over 800,000 per year in the U.S. The average cost was $44,110 per procedure in 2004. Since the operation tends to be performed on older Americans, Medicare covers most patients and compensates US$10,000 to $15,000 for each case.

Reuters reporter Julie Steenhuysen writes that angioplasty is “big business for medical device makers including Boston Scientific Corp, Medtronic Inc, Abbott Laboratories Inc and Johnson & Johnson”. Dr. Raymond Gibbons, a professor of medicine who specializes in cardiology at the Mayo Clinic in Rochester, Minnesota, criticizes the current U.S. health care system for compensating doctors based upon procedures performed rather than for following recommended practices.

A stress test in which the patient walks on a treadmill is recommended to determine whether a partial obstruction impairs heart function. Although not all patients who need angioplasty are strong enough to undergo the stress test, UC San Francisco researchers were surprised that testing preceded so few of the surgeries.

Professor of medicine Dr. Rita F. Redberg told U.S. News and World Report, “We didn’t expect to find 100 percent, but we expected a much higher percentage than 44”. Dr. Redberg co-authored a report on the findings for the Journal of the American Medical Association this month.

Dr. Grace Lin, another co-author of the study, noted: “What really matters is whether or not that blockage is affecting blood flow to the heart. That is why the stress test is important.” Their research analyzed over 23,000 Medicare cases and over 1,600 commercial insurance cases.

American Heart Association president Timothy Gardner called the study “a good wake-up call” to remind medical doctors to make sure they do not perform unnecessary procedures. Dr. Gardner regards the study as evidence that many unnecessary angioplasties are being performed.

The study found great variation in the rate of stress testing. Geographic areas ranged from 22% to 76% with the highest rate of testing in the Northeastern and Midwestern states. Testing rates also varied by gender, with men more likely to receive a stress test than women, and by other factors including the age of the physician. Dr. Gibbons points to some of these variances as indications that some physicians may be performing angioplasties indiscriminately.

Not all physicians agree. Although the various types of stress testing usually cost a few hundred dollars instead of tens of thousands, the chief cardiologist at University of Wisconsin Hospital and Clinics Dr. Matthew Wolff notes that stress tests yield false negative results in about 10% of cases. In his opinion, doctors who rely on stress tests “are going to be missing people with severe disease.” Although he agrees that some angioplasties are unnecessary, he contends that the new study does not offer a solution to the dilemma.

The American College of Cardiology plans to release new guidelines soon to help doctors determine when a stress test is appropriate, yet the payment system lacks a financial incentive to abide by testing guidelines. Dr. Eric Topol of Scripps Translational Science Institute in La Jolla, California noted the underuse of stress tests in a study of private insurance records 14 years ago. Dr. Topol agrees that testing guidelines “should be much more clear-cut”, and adds that stress tests ought to be performed annually. “You can do a stress test every year to be sure things are normal. That is an important baseline that is being ignored all too frequently.”

Cardiologist, Dr. Anthony DeFranco of Aurora St. Luke’s Medical Center, considers stress testing to be appropriate in at most 65% of cases, since a substantial minority of patients have other health problems that prevent them from undergoing the test.