Doctors who invest in expensive heart-testing equipment for their own offices are more likely to order—and bill for—unnecessary heart tests, according to a study published today in the Journal of the American Medical Association.

Researchers from the Duke University Medical Center in Durham, N.C., looked at how often heart patients recovering from angioplasty or bypass surgery had a follow-up nuclear stress test or stress echocardiography within 30 days of being discharged for their procedure. Expert guidelines say that the tests, which involve using radioactive material or sound waves to assess heart function, are generally not necessary in the first few years after the procedures unless the patient experiences symptoms, the authors say.

But in their analysis of the health insurance records for roughly 18,000 heart patients, the researchers found that patients of doctors who billed for both technical and professional fees—an indication that the doctors owned the medical equipment themselves—were more than twice as likely to undergo a nuclear stress test and more than seven times as likely to undergo stress echocardiography than patients of doctors who did not bill for those fees.

The researchers also found that up to one in 10 patients who did not report having heart symptoms at their outpatient visit still underwent stress testing.

An editorial accompanying the article warned that more and more doctors, especially cardiologists, have now invested in expensive testing technology, including MRIs, CT scans, and cardiac stress imaging. “The financial benefits of such arrangements are clear as evidenced by their popularity—almost 1 in 5 physician practices report owning or leasing equipment for advanced imaging,” write the authors, Brent K. Hollenbeck, M.D., and Brahmajee K. Nallamothu, M.D., both at the University of Michigan in Ann Arbor.

John Santa, M.D., M.P.H, director of the Consumer Reports Ratings Center, says:

This provides more evidence that doctor’s decisions are often influenced by financial priorities.

And it’s not just people recovering from heart procedures who sometimes get unnecessary tests. Our survey last February of some 8,000 Consumer Reports subscribers without symptoms of heart disease found that many got tests they probably didn’t need, including electrocardiograms (ECGs) and exercise stress tests.

For details, see our advice on the heart tests you need and our Ratings of heart-screening tests.

Sources
Association Between Physician Billing and Cardiac Stress Testing Patterns Following Coronary Revascularization [JAMA]
Editorial: Financial Incentives and the Art of Payment Reform [JAMA]