Mar 04 2008
There is a new industry offering preventive health screening services direct to the public. A few years ago it was common to see ads for whole body CT scan screening at free-standing CT centers. That fad sort of faded away after numerous organizations pointed out that there was considerable radiation involved and the dangers outweighed any potential benefits.
Now what I most commonly see are ads for ultrasound screening. In fact, I am sick and tired of finding them in my mailbox and between the pages of my local newspaper. Ultrasound is certainly safe, with no radiation exposure. It sounds like it might be a good idea, but it isn’t.
Life Line Screening advertises itself as “America’s leading provider of quality health screenings.” They offer “4 tests in less than 1 hour – tests that can save your life.” They travel around the country, setting up their equipment in community centers, churches, and YMCAs. For $129 you get ultrasounds of your carotid arteries, your abdominal aorta, your legs, and your heel bone. They mail you your results 21 days later.
They had celebrity endorsements. Peggy Fleming urged me to make an appointment for screening. I wrote her and told her why I thought her advice was bad. I never got a response, but I don’t see her name on the website any more, so maybe she listened.
Besides “Peggy Fleming says so,” the website offers five reasons to get screened:
(1) Stroke is the leading cause of serious, long-term disability, and the third leading cause of death in the US.
(2) 700,000 Americans suffer a stroke each year, one every 45 seconds.
(3) Most people who have strokes and aneurysms do not experience symptoms. [I think they meant before the stroke; surely patients have symptoms when the stroke occurs.]
(4) 12 million Americans suffer from Peripheral Arterial Disease (PAD). They are 4-5 times more likely to die of a heart attack.
(5) Life Line Screening offers painless, inexpensive, and non-invasive preventive health exams right in your neighborhood.
No, I’m sorry but those are not reasons to get screened. That’s like saying that lots of people die from cancer and Life Line takes pretty photographs so I should let them take my photograph. If screening reduced morbidity and mortality, that might be a reason to get screened, but they are not claiming that. They can’t claim it, because there is no evidence to support doing these tests in the general population.
For a screening test to be worthwhile, it has to meet several criteria. You want to know the predictive value of a positive test in the population being screened. You want to know not just whether it picks up an abnormality, but whether picking up that abnormality will allow earlier treatment that will make a difference in outcome. You want to know whether false positive tests will lead to harmful invasive procedures. Bottom line: does the test do more good than harm?
These tests are worthwhile when used by doctors to help diagnose patients with symptoms or patients at high risk, but when used to screen the general population of mostly healthy people, they are likely to be useless or even to do more harm than good.
Ultrasound can show a narrowing of the carotid artery. I guess that’s nice to know. It’s also nice to know that if you have no symptoms, it’s probably not going to make a difference. Even if the artery is 60-99% blocked, surgery may only reduce the risk of stroke by 1% a year, and the surgical risks may outweigh any benefit. If you have symptoms from carotid artery narrowing, surgery might be life-saving. But then you probably would have consulted your doctor about the symptoms in the first place instead of going to a church to get a screening test. If you have an asymptomatic narrowing that does not require surgery, you can work on reducing your other risk factors for stroke, but that would be a good idea anyway, even if you didn’t know what your carotid arteries looked like.
Ultrasound screening for osteoporosis is not very accurate. About 50% of people screened will be told they are OK. The other 50% will have to be tested further with a DEXA test. If you’re going to be tested, why not get the more accurate DEXA test in the first place?
If your screening test shows PAD, there’s not going to be anything you can do about it other than exercising and not smoking. Why not encourage everyone to exercise and stop smoking instead of bothering with a screening test?
Various medical organizations and the United States Preventive Services Task Force (USPSTF) have put great thought into recommending which screening tests are worthwhile for the general public. Their current recommendations include:
(1) Carotid artery screening not recommended.
(2) Abdominal aortic aneurysm screening recommended only once for men between the ages of 65 and 75 who have ever smoked.
(3) Screening for PAD not recommended.
(4) Osteoporosis screening recommended only for women over the age of 65 (or 60 if they have risk factors).
The evidence indicates that screening outside these guidelines is not likely to benefit patients. It does not improve patient-oriented outcome in any significant way and may cause harm from undue worry, expense, further testing that may be invasive, unnecessary surgery, etc. The Life Line folks do not tell their customers any of this. They let them assume that the tests are life-saving, can prevent strokes, and are highly recommended.
In the last flyer I got, they have mysteriously replaced the osteoporosis part of the screening with a new test: atrial fibrillation testing, with an EKG rhythm strip. And the price has gone up to $139. A press release capitalizes on the fact that Dick Cheney was in the news with this diagnosis last fall. This is no more than shameless exploitation.
AF screening might be a good idea, but it is not even mentioned by the American Heart Association, the American Stroke Association, the American Academy of Family Physicians, the USPSTF or any other organization I could find. We simply don’t have any good data that population screening for AF reduces the risk of stroke, morbidity or mortality. One study suggested that teaching people to check their own or another’s pulse for irregularity might be an effective, low-cost way to make the diagnosis. One consideration is that the treament of AF carries risks of its own. Before AF screening can be recommended for the general public, we need to know whether giving all those extra people blood thinners and surgery will do more good or harm overall.
The Life Line company is making a profit by feeding its customers misleading information. Insurance and Medicare do not cover Life Line screening, although they usually do cover the kind of screening tests recommended by the USPSTF. I have been unable to find out whether the venues that offer them space (churches, etc.) charge them for that space or offer it as a supposed public service. If they offer it free, it is not genuinely of service to the public. Either way, they are contributing to the company’s profits by sharing their prestige. Their support implies that they endorse the screening.
I think what Life Line is doing is unethical. Let me make this clear: I have no objections to any consumer getting any screening test, whether it is recommended by the USPSTF or not. It is not unethical to offer these tests. What is unethical is withholding information that the average reasonable person would like to know before making a decision. If Life Line informed their customers that the tests are not recommended by any medical authority and explained why, then the customers could give informed consent to the screening. Instead, customers are only told the tests can help them avoid a stroke or save their lives.
I’m all for patient autonomy, but only if patients have access to the pertinent information.
If Life Line were seriously interested in improving health rather than just making profits, they would be concentrating on screening tests of proven value like blood pressure screening, and they would be addressing the most significant modifiable risk for health: smoking.
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