In the words of the cantankerous Dr. Gregory House of TV fame, CT calcium scan screening tests are
“…useless because you could probably scan every one of us and find 50 doo-dads that look like tumours”.
That’s not quite what those who are promoting these screening scans tell us. They tell us that we really should be forking over $600-$3,000 to them in order to get a CT (computed tomography) calcium scan to screen for possible disease.
I’ve been seeing more and more ads marketing full-body or heart screening scan services at for-profit clinics, shopping malls, church basements, and even in tractor trailers hauling imaging machines. One ad for a CT heart screening scan promised that it can:
“…detect calcium deposits (or the hardening of plaque) in the arteries of the heart. This is useful information if determined early, prior to a heart attack. With this knowledge, a person may be empowered to change his or her lifestyle and slow the progression of heart disease or even prevent a heart attack.”
“May be empowered to change”? Why would you have to spend $600 – $3,000 to “empower” yourself to start improving your lifestyle? Here’s a cheaper alternative: send me 50 bucks now and I’ll empower you right upside the head to quit smoking, eat more veggies, and do more exercise from this day forward.
I decided to contact WomenHeart: The National Coalition For Women With Heart Disease to get their take on this issue. WomenHeart staff consulted a number of the health care professionals who serve on their Scientific Advisory Council how they would reply to my query. Here are a couple of the Council responses:
• “I do not recommend full body or cardiac calcification scans in healthy individuals for disease screening.”
• “No major organization endorses the use of total body scans.”
They also sent me this article on what heart scans can and cannot do for you. Most major health agencies (like the American Heart Association, the American College of Radiology, the American Cancer Society) do not recommend routine use in people without heart-related symptoms.
Over time, a mix of calcium, fat, cholesterol, cellular waste and fibrin build up in your coronary artery walls as plaque. In response to plaque build-up, cells in your artery walls can multiply and secrete additional substances that can worsen the state of those arteries. These deposits are very common, and may start in children as young as 10. But while artery-hardening calcium may indicate disease is present, a heart attack actually occurs when a soft kind of unstable or “vulnerable” plaque ruptures in the coronary artery wall and causes blood to clot.
These CT heart scans, however, can’t see this dangerous soft, unstable and vulnerable plaque – only hard calcium. And if you’re a woman with heart disease, according to the February 2010 issue of the American Journal of Cardiology, you’ll likely have less of this calcified plaque than men anyway.
Another report in the Journal of the American College of Cardiology suggests that even for patients whose coronary calcium score was zero (no calcium found on scans), significant artery blockages were still found. Researchers, for example, identified fully occluded blood vessels among study participants, of which 20% showed no calcium.
Researchers like Dr. Angelo Secci of UCLA, writing in the journal Circulation, concludes:
“Coronary calcium appears to be a weak predictor of coronary death and heart attack.”
Dr. Jerome P. Kassirer, professor at Tufts University School of Medicine and former editor-in-chief of the New England Journal of Medicine, told Junkfood Science that what appears to be behind the heavy promotion of these calcium screenings, despite the fact that no sound evidence supports their use, is a profit motive that’s chillingly outlined in this New York Times article.
Cardiologist Dr. Rita Redberg claimed recently in the Archives of Internal Medicine that she “was troubled to read” that during his recent physical examination, U.S. President Barack Obama had received a coronary calcium screening scan. Dr. Redberg wrote:
“This screening test likely exposed Mr. Obama to significant radiation unnecessarily, increasing his risk of future cancer. A single electron beam CT scan can deliver 100 to 400 times more radiation than a traditional X-ray. In light of this radiation risk, and the lack of proven benefit in low-risk persons, the US Preventive Services Task Force (USPSTF) recommends against this test in people such as Mr. Obama. In addition, the leading professional cardiology societies do not recommend coronary calcium screening.”
The USPSTF had earlier not only found “no credible evidence to support calcium screenings for coronary heart disease” in low-risk people, but in fact, it had even specifically recommended against:
- routine screening with resting electrocardiography (ECG)
- exercise treadmill test
- electron-beam computerized tomography (CT) scanning for coronary calcium for either the presence of severe coronary artery stenosis or the prediction of coronary heart disease events in adults at low risk for coronary heart disease events.
- routine screening “in adults at increased risk for coronary heart disease events.”
- carotid artery screenings (which received a D recommendation by USPSTF, meaning they should be actively discouraged)
The task force found no evidence that these screenings improve health outcomes for most adults, but instead, because false-positive test results are likely to cause harm, “including unnecessary invasive procedures, over-treatment, and labeling, the USPSTF concluded that the potential harms of routine screening for heart disease in this population exceed the potential benefits.”
“It is a commercial enterprise that bypasses sound medical principles and judgment. These entrepreneurs proffer a promise that they know they cannot fulfill. It’s a scam clad in a white coat.
“For the majority of their unsuspecting customers, a positive result will be wrong and a negative result will guarantee nothing. I realize that an ordinary patient will celebrates when his total body scan is negative, but this is not how medicine works. You can have a normal EKG performed weekly, but this will not prevent a heart attack or exclude significant coronary artery disease.”
Dr. Stephen Barrett of QuackWatch agrees:
“If CT scan is negative, the individual has a low (but not zero) probability of having coronary artery disease. Nor is it considered useful to measure coronary calcium in patients who have already had a heart attack or undergone coronary bypass surgery or coronary angioplasty. There is no current reason to believe that the benefits of heart or full body scanning exceed the risks for apparently healthy individuals. Scans have not been proven to be either cost-effective or effective in prolonging life.”
Dr. Larry Kessler, the FDA’s director of the Office of Surveillance and Biometrics, said:
“We’ve sold ourselves the myth that getting everything early is always good.”
Odds are that scans will either find nothing, or that they’ll find something that is harmless. Either way, they may cause you more loss of sleep before you find out that you do not have a serious disease after all.