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  • Excessive or unnecessary screening can lead to a cascade of obligatory follow-up costs down the line, along with potentially invasive treatments you didn’t really need, and the psychological trauma that goes along with it
  • Two common screening tests that can potentially do more harm than good are annual mammograms for women, and the annual PSA test for men. Studies have shown that these tests have no impact on mortality rates, and far more people are harmed from unnecessary treatment due to these tests than are saved as a result of early diagnosis
  • A recent meta-analysis study found that general health checks did not reduce morbidity or mortality, neither overall nor for cardiovascular or cancer causes, although the number of new diagnoses was increased
  • Another study warns against placing too much faith in medical studies showing very large effects of medical treatment (benefits or harms). The massive analysis tracked the fate of thousands of studies, from the effects demonstrated in the initial study, compared to the effects elucidated in subsequent trials. In 90 percent of cases where “very large” effects were initially reported, such effects shrank or vanished altogether as subsequent studies were done to confirm the results
 

General Health Checkups and Medical Screening Tests—Do You Really Need Them?

November 25, 2012 | 170,479 views
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By Dr. Mercola

Alan Cassels, a drug policy researcher at the University of Victoria in British Columbia, has written several books about the drug industry. His latest work is called Seeking Sickness: Medical Screening and the Misguided Hunt for Disease.

This book is loaded with helpful information about medical screening, and really focuses on an important topic, which is prevention.

It's been a longstanding passion of mine to prevent disease rather than to treat it, because it's so much easier to implement a preventive strategy. There is an enormous amount of effort and research invested in the traditional community into medical screening procedures.

The trouble is, conventional medicine views these medical tests as "prevention," when in fact there's nothing preventive about them at all. They're just diagnostic tools, and some aren't even all that accurate at that. Worse yet, some may be risky, and do more harm than good.

"I've been following the marketing tactics of the pharmaceutical industry for almost 18 years now," Cassels says. 

"I came upon screening partly because I started to see that a lot of people who ended up being put on certain regimes ended up there because they'd been through some screening regime – perhaps a screen for their blood cholesterol, a screen for their eyeball pressure, or even something simply as benign as screening for high blood pressure.

I started to look upstream from the pharmaceutical industry and really look at the kind of tactics that were used to entrap more and more people into drug regimes. And screening... is very pervasive."

To Screen, or Not to Screen?

A recent article in The Atlantic1, written by Oklahoma physician John Henning Schumann, MD, brings up the issue of over-screening—medical tests that simply are not necessary, or worse, detrimental. He discusses the case of one of his patients, who brought in results obtained from a "medical screening fair" at her local church.

The test was advertised as a bargain at $129, but according to Dr. Schumann, it was a complete waste of money considering she didn't have any risk factors warranting the testing. Besides relieving her of some hard-earned money, all it did was make her anxious when she really didn't need to be.

"I love America and the free market. I love companies that make a buck with hard work and ingenuity..." he writes. "But I don't love when innocent people get fleeced in the name of bad medicine that pretends to be good. Worse yet, when it happens at church. Commercial screening companies fiendishly target churches to find parishioners looking for healthy bargains. If your local church is endorsing a "health screening fair," it must be good, right?"

Yes, churches, synagogues and other houses of worship have recently been targeted by the medical industry in an effort to increase business. This became woefully apparent last year, when the White House Office of Faith-Based and Neighborhood Partnerships, co-sponsored by the U.S. Health and Human Services, the Office of Minority Health, and the CDC, held an invitation-only, off the record call2.

The focus of the call was on getting faith-based organizations to sponsor flu clinics with Walgreens. As an example, they cited a priest who stopped in the middle of mass to roll up his sleeve and get vaccinated, inspiring the rest of his parish to line up behind him. This has nothing to do with promoting good health. It's just another marketing shtick, and a potentially dangerous one at that. I'm sure the priest in question didn't stop to recount the many potential side effects before his flock took to the line to follow his lead.

"She didn't need these screening tests, and I'll tell you why," Dr. Schumann continues.

"As a non-smoking daily walker, her chance of having peripheral arterial disease (blockage of the leg arteries) is vanishingly small. The ultrasound of her abdomen, to search for an aneurysm of the aorta, is also a waste of money since her likelihood of having the condition borders on the absurd. The same is true for the ultrasound she received of her carotid arteries. In fact, the country's most influential (and controversial) authority on screening, the U.S. Preventive Services Task Force, recommends against all of the tests Mildred underwent as routine screening tests.

The broader issue on why excessive screening is bad is that it can lead to a cascade of obligatory follow-up costs down the line... Companies should not play on our fears to sell us unnecessary screening exams. When they do, we should be confident that we're better off not buying them."

Routine Health Checks Found to Have No Benefit

In related news, a recent study by the Cochrane Library3, the gold standard for independent medical reviews, found that:

"General health checks did not reduce morbidity or mortality, neither overall nor for cardiovascular or cancer causes, although the number of new diagnoses was increased. Important harmful outcomes, such as the number of follow-up diagnostic procedures or short term psychological effects, were often not studied or reported and many trials had methodological problems. With the large number of participants and deaths included, the long follow-up periods used, and considering that cardiovascular and cancer mortality were not reduced, general health checks are unlikely to be beneficial."

This may sound shocking to many, as general health checks are typically considered to be part and parcel of early disease detection and prevention. However, after reviewing the health outcomes of nearly 183,000 people, the researchers found that, in terms of making you live longer, getting regular health check-ups doesn't appear to make a difference...

Regular screening may however increase your drug use, and you may receive a diagnosis and treatment for a condition that might never have led to any symptoms or had any impact on your longevity. According to lead researcher Lasse Krogsbøll4 of The Nordic Cochrane Centre in Copenhagen, Denmark:

"What we're not saying is that doctors should stop carrying out tests or offering treatment when they suspect there may be a problem. But we do think that public healthcare initiatives that are systematically offering general health checks should be resisted."

This isn't the first time researchers have concluded we may be over-testing and over-treating. In fact, over the past few years this has become increasingly studied, and most analyses concur that more testing and more aggressive treatment does not translate into reduced mortality. Naturally, there's no way to make recommendations here that could apply to everyone or even most people. Evaluating your risk factors is one important factor of course, as stated in Dr. Schumann's article. Evaluating your symptoms is another. If you're asymptomatic, maintain a healthy, active lifestyle, and don't have any risk factors, perhaps signing up for a bunch of medical tests at your local church, "just in case," is not in your best interest.

Medical Screenings—Heavily Promoted to Increase Sales of Post-Screening Activity

Alan Cassels also has something to say about this:

"[S]o much of what we consider to be disease in the orthodox medicine world has been created, has been shaped, and has really been molded by the pharmaceutical industry," he says. "And very much what we consider to be medicine is determined by the kinds of things that end in what the drug industry calls the 'drug successful visit.' Not just anything that we potentially could be sick with, but anything that any healthy person could get.

And really, screening is about looking in healthy people to find signs of disease.

I want to distinguish right off the bat that when I'm talking about screening, I'm talking about people who have no symptoms, who are otherwise healthy, and who have really no reason to consult the doctor or being told, 'You need to be proactive. You need to seek out early signs of disease. That's a good thing to do to keep yourself healthy.' People that actually have symptoms – feel a lump or whatever – and then go in for a test, that's a diagnostic test. That's something different.

I'm talking about a screening test where you're taking otherwise healthy people and trying to find signs of disease in them."

Common Cancer Screens Can Do More Harm than Good

Much like myself, Cassels research has led him to seriously question common tests like mammography for breast cancer, and the PSA test for prostate cancer. In the interview above he explains:

"[O]ne thing that we know for sure is that a lot of the activity around screening makes a lot of money for a lot of people. One example might be the whole world of mammography... [W]e're telling healthy women who have no symptoms, 'Go in every year. From the day you turn 40, go in once a year, and have your breasts radiologically screened.'

What we're not telling women is that just the act of screening involves a whole downstream potential for harm and also involves huge amounts of certain medical resources in terms of the radiologist, the surgeons, and so on.

It's a huge industry. You might say, 'Well, what's wrong with that industry if it's actually saving lives?' Well, when you sit down, and you look at the number of women that have to be screened in order to have one woman benefit, it's actually quite shocking... The best studies (these are studies that are over 10-years long and done in Canada, the U.S., and in Europe), have found that you have to screen 2,100 women every year for 11 years to prevent one death. So, to answer the question, 'Is it lifesaving?' Yes. One in 2,100 women would benefit from being screened over an 11-year period.

But at the same time, of those 2,100 women, about 600 to 700 of them will have a false-positive. They will find something unusual or something abnormal, and that will require biopsies, open surgeries, mastectomies, and so on. Not to mention the psychological harm of inflicting a cancer scare... The problem is that you're generating a huge amount of activity to save one in 2,000 women. In the best-case scenario, you're causing 600 or 700 women to have huge amounts of procedure... It seems to me that it's an awfully high cost to pay to prevent one death.

And I think that there are many, many other things that we can do to try to reduce the risk of breast cancer in women rather than telling them to get their annual mammography screen."

The male version of mammography is the annual PSA test. It's a simple blood test that measures the level of an antigen in your blood. An elevated reading could indicate that you have prostate cancer, or are at increased risk of developing prostate cancer. Or not, as the PSA test is notoriously inaccurate...

"What most men aren't being told – this is from the research that I did – is when they're given that test, the likelihood of them finding cancer cells in their prostate are fairly high," Cassels explains.

"In fact, it's directly proportional to your age. If you live to be 60 or 70 years old, there's a good chance you're going to have a 60 percent chance of having some evidence of prostate cancer. You might say, 'Wow, if you've got prostate cancer, shouldn't you do something about it?'

Well, certainly with the PSA test and its lack of specificity and accuracy, you've got 60 or 70 percent of the male population that will develop prostate cancer in their lifetime. But only about three percent of men will die from prostate cancer.

What doctors have told me is that most men will die with prostate cancer, but not because of it. And that's really kind of a mindblowing concept for a lot of people, because they think what you're saying is that, 'I can have a cancer in my body and live a perfectly, long, and healthy life.' Absolutely.

One of the things that screening is good at is finding signs of disease. What it's not very good at is finding disease that matters. In this case, having an elevated PSA level could be caused by a whole range of things. And if you're otherwise asymptomatic, going down that line of getting tested will lead to biopsies, possibly surgery, other kinds of treatment including chemotherapy, and hormone therapy. At the end of the day, a lot of the men that go through that mill end up becoming incontinent or impotent because of the treatment."

Medical Science Rarely a Slam Dunk

In related news, a recent study5 by Dr. John Ioannidis of the Stanford School of Medicine in California warns against placing too much faith in medical studies showing very large effects of medical treatment (benefits or harms). The massive analysis tracked the fate of thousands of studies, from the effects demonstrated in the initial study, compared to the effects elucidated in subsequent trials.

Interestingly, in 90 percent of cases where "very large" effects were initially reported, such effects shrank or vanished altogether as subsequent studies were done to confirm the results. Dr. Ioannidis told Reuters6:

"Our analysis suggests it is better to wait to see if these very large effects get replicated or not... Keep some healthy skepticism about claims for silver bullets, perfect cures, and huge effects."

Typically, studies reporting very significant effects are based on smaller, less reliable experiments. This is because small trials are more likely to be skewed by chance alone. The authors also point out that studies showing very large effects rarely address mortality, and are more likely to address laboratory-defined efficacy. Alas, changes in lab values does not necessarily equate to improved health... Sometimes, this kind of efficacy could actually be disastrous.

Dr. Andrew Oxman of the Norwegian Knowledge Centre for the Health Services in Oslo, who wrote an editorial7 about the study, told Reuters8:

"'There are lots of examples where things start to be used and have entered the market based on surrogate outcomes and then actually proved harmful.' He mentioned the heart rhythm drugs encainide and flecainide, which for many years were given to people with acute heart attacks. But then trials showed they were actually bad for these patients. 'These drugs were by given well-meaning clinicians, but they actually killed more people than the Vietnam War did,' Oxman said.

Statins are another perfect example of this, as they are very effective at reducing your cholesterol level, yet wreak all sorts of havoc in your body while doing so. If you're not careful it may even lead to premature death. Your cholesterol numbers will probably be a-okay though, if that brings any relief to anyone, and your death will be chalked up to some other health problem.

According to Cassels:

"[W]hen you look at the big meta-analyses of statin drugs, there are about five major studies that have tens of thousands of patients in them... testing drugs like simvastatin or atorvastatin (Zocor or Lipitor). When you look at the totality of those studies, the one thing that you find is that the benefit, in terms of reduction in heart attack or stroke for people who haven't had a heart attack or stroke (we're talking primary prevention), is simply not there.

You can alter cholesterol quite easily using cholesterol-lowering drugs. But the question is, 'What's important? Having your cholesterol altered or reducing your risk and reducing the chance that you could have a heart attack?'

I think that the main thing that has happened... [is that] we focus on the numbers... when in fact, what really counts is whether you have a heart attack or stroke.

Of course, it takes long-term studies, five- and 10-year long studies, to determine whether drugs will prevent that. And certainly in the primary prevention population, you don't see any reductions. Women don't benefit from having their cholesterol altered with statins, and certainly [not] the elderly. Some of the newer research is showing that older people who have higher cholesterol actually have a protective effect from that."

Final Thoughts

Of the tens of thousands of treatments evaluated in Dr. Ioannidis study, only one stood out as a clear "slam dunk" in terms of the benefit of treatment. A respiratory intervention in newborns repeatedly demonstrated a reliable, very large drop in death rates. That really tells us something about "evidence-based medicine," doesn't it?

It's not at all as clear-cut as conventional doctors and health authorities would like us to believe. Today, I think many treatment recommendations, especially in terms of drugs and vaccines, are clearly premature and based on very flimsy evidence. The same applies to many of the medical screening tests available. The evidence of real benefit simply isn't there in many cases.

"I guess the summary statement is: go into the screening with your eyes wide open," Cassels says.

"And that is to say that it's not an emergency procedure. If you're being offered a screen of any sort whether it's a mental health screen, a screening of osteoporosis, for blood pressure, cholesterol, or for cancers, take the time to ask the questions. 'How could I be hurt by this screening?'

When you actually understand that a screening can potentially harm you, you might take a very different approach to rushing into it. You might take more time to actually do some research. And really when you do research, it's important that you look at independent sources of information.

... The United States Preventive Services Task Force—their stuff is all available on the Internet. In terms of the spectrum of trustworthiness, I would place that in the More Trustworthy category, as opposed to the other category, which might be those groups that stand to benefit from screening and over-promote and overpromise on screening's benefits. So, really, independent information is I think key, and knowing that screening can potentially harm you."

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