The Danger of Too Many Tests By Dr. Ranit Mishori

The Danger of Too Many Tests By Dr. Ranit Mishori

http://www.parade.com/articles/editions/2008/edition_07-06-2008/3Too_Many_Tests

If you’re like most Americans, your health bills are soaring. One reason is the “diagnostic imaging” industry, which includes X-rays, CT scans, and MRIs—the tests that let doctors “see” our bones, blood vessels, nerves, muscles, and organs. According to the American College of Radiology, imaging is one of the fastest-growing services in medicine, with costs reaching approximately $100 billion annually.

The detail revealed by these tests can be astounding, the information lifesaving. But are we overdoing it? Are all those tests really necessary? And is harm potentially being done?

Some researchers worry about overexposure to radiation. While noting that many lives are saved by imaging, Dr. David Brenner, director of the Center for Radiological Research at Columbia University Medical Center in New York City, estimates that “1% to 2% more cases of cancer may result from the increased use of imaging in the future.” Of special concern: Some 5 million CT scans are performed annually on children, who are 10 times more sensitive to radiation than adults.

Further, imaging may result in “false-positive” results (finding a problem that does not in fact exist) or “incidental findings” (seeing an abnormality that may be clinically harmless), notes Dr. Stephen Baker, chair of the Department of Radiology at the UMDNJ-New Jersey Medical School. Both results often lead to even more imaging and risky invasive procedures, including surgery.

Not every ache and pain calls for a scan or an X-ray. It’s best to know where and how imaging tends to be overused.

CT Scans
Computed Tomography (CT) scans, also known as CAT scans, are the “doughnut holes” patients can find themselves in. CT scans are particularly good for looking at organs, bone, soft tissue, and blood vessels. However, their radiation levels can be quite high—“typically the equivalent of about 100 conventional X-rays,” says Dr. Brenner. CTs are routinely ordered for headaches, heart imaging, and full-body scans, but there are reasons to question their use for each.

Headaches. CT scans are requested for many of the 45 million patients who suffer from headaches to rule out their greatest fear: a brain tumor.

Numerous studies suggest, however, that this is overkill. Most headaches are not indicators of something serious—a tumor or brain bleed. Furthermore, these more-serious problems almost always are accompanied by other, visible symptoms, such as seizures and neurological impairment. For example, Sen.Ted Kennedy’s recent brain tumor diagnosis involved clear seizure activity. In the absence of such red flags, a scan probably is not worth the risk of increased radiation exposure. This view has been endorsed by a panel of experts, including the American Academy of Neurology.

Heart imaging. Coronary CT angiography is a relatively new procedure that gives a detailed view of the heart and the arteries that supply it with blood. It allows doctors to see calcium deposits and blocked arteries without inserting tubes or needles. This test has become quite popular, but it also raises concerns because of the frequency of false-positive and false-negative results. Furthermore, in addition to radiation exposure, there is the risk from the contrast dye used, which can lead to allergic reactions and kidney damage.

At present, there are no clear guidelines for when a coronary CT is clinically appropriate. It appears that the test can benefit those who have symptoms that suggest heart disease or who are at high risk for heart disease. But healthy individuals should not rush to request this test.

Full-body scans. CT scans of the entire body—a virtual physical, where every inch of your body is scrutinized from the inside—have been marketed in recent years to perfectly healthy individuals. But experts—including those at the American Cancer Society, Food and Drug Administration (FDA), and American College of Radiology—agree that these scans are not a good idea for healthy people without any symptoms. The scans often find irregularities that are entirely harmless but nevertheless lead to many expensive, unneeded, and invasive procedures.

X-rays
This classic imaging tool is useful for looking at bones and the chest.

Chest X-rays. Doctors often order chest X-rays for routine evaluation before surgery. While it certainly makes sense to do so in certain cases—for those whose surgery involves the heart or lungs, for example—there is increasing evidence that general testing is not advantageous. A recent extensive review in the United Kingdom found that chest X-rays may lead to false-positive results and expose patients to unnecessary radiation.

Back pain. Despite the discomfort associated with lower back pain, the vast majority of patients (90%) recover within 6-8 weeks, and most do not need X-rays, MRIs, or CT scans of their lower back. Imaging should be reserved for those cases where a serious underlying condition is suspected.

Magnetic Resonance Imaging
Magnetic Resonance Imaging (MRI) provides excellent views of the soft tissues of the body, so it is very useful in brain and cancer imaging. Unlike CTs or X-rays, MRIs do not emit radiation—they use a magnetic field to create images—but they are much more expensive than simple X-rays.

Achy knees. These days, MRIs frequently are ordered for patients with knee pain due to arthritis, because they provide a detailed view of the knees, bones, cartilage, and ligaments. But MRIs may not be necessary to diagnose a common condition such as osteoarthritis. A study presented this year at the American Academy of Orthopaedic Surgeons’ annual meeting suggested that, in most cases, X-rays are sufficient to determine who needs knee-replacement surgery. The cost difference translates into millions of dollars: MRIs are billed anywhere from $1200 to $2500 per session, whereas knee X-ray billing falls under $200.

Why Is My Doctor Ordering It?
There are several reasons behind the trend of excessive imaging. Together with your doctor, you, the patient, can play a part in finding the right balance for their use.

Short appointment times. With less time available to spend with patients, some doctors may order images as a shortcut—a way to get quick answers.

Malpractice fears. Excessive litigation forces doctors to practice defensive medicine. Even if there is little chance of a serious disease or condition, a physician may order a test to reduce the risk of being sued later for missing something important.

Where the money is. A growing number of physicians own diagnostic facilities or equipment. Some may have an incentive to order tests, because the fee goes to their own bottom line.

Patient expectations. Many patients want what they consider “the best”—sophisticated technologies like CT scans or MRIs—and doctors are quick to comply even if they don’t really see the need.

Patient reassurance. Sometimes, all evidence aside, it is easier to lower a patient’s anxiety by pointing to an actual CT image and saying, “See, there is no tumor there.” In some cases, a picture may be worth 1000 words (or dollars).

Do You Really Need It?
Learn about the various tests and what each is best for. Then talk with your doctor about the risks involved, such as radiation and false-positive results. Ask:

• Why is a specific imaging test necessary?

• How certain are you about the diagnosis without the scan? A medical history and physical may be enough for a diagnosis and treatment plan.

• How will test results affect treatment decisions?

• Does another, safer test exist that would give me the same information?

Be sure to request a copy (a CD-ROM or a written report) of any CT scan or other imaging study you have done. That will save you the trouble (and radiation) of having the same exam twice if you go to another hospital, move to another town, or change doctors.