Lakeside Medical Musings

$creening Te$t$

There are many reasons why the field of medical testing has grown exponentially over the past fifty years, and most of those reasons are not tied to quality patient care.  Plainly speaking, medical testing is where the big money is.  Physicians, hospitals, and healthcare systems all make huge dollars testing patients. While some of this testing is essential, a tremendous amount of it is of dubious value, and some of it can give such poor information that it’s actually of negative value to the patient. While the actual charge for an office visit to your primary care physician may be $100,  the testing associated with this visit can easily run to the thousands of dollars, and yes, your medical provider derives a good deal of the profit from the testing that he or she orders, and this only incentivizes the rampant practice of over-testing.  This is an economic fact of life in our current “fee for service” medical world.  Patients themselves are not blameless in this situation as they often arrive for their medical appointment with a list of the blood tests or X-rays that they believe they need, just as they often arrive with the names of the expensive prescription drugs they’ve seen advertised on television. You know the ones – “Ask your medical professional if Lyrica (or Viagra or Celebrex or Humira… the list goes on and on…) are right for you!” Patients actually like to be tested for ailments, as they have grown accustomed to feeling that tests give black and white, yes or no, answers to medical issues – as their experience has shown them with a strep test or a urine culture for a UTI — but there are so many tests available now that often have only gray answers; patients demand them anyway because they feel “some” information is better than none.   As a trained physician with years of clinical diagnostic experience, let me tell you, that is often not a true statement.

“Medical screening” allows for the identification of an asymptomatic disease, harmful condition, or risk factor. Screening, or testing, to find disease at an early stage, or to identify a risk for the future development of disease, is the backbone of preventative medicine; and screenings are a very useful and important tool, when used properly.  But early detection of a disease is not enough. If there isn’t an effective treatment for the disease — so that finding it at an early stage improves the outcome for the patient – is there a reason to have a test for it that costs $1,000? There has been much research trying to find a screening test to detect early lung cancer in smokers, the most common cause of cancer death in the US for both men and women.  For years, no screening testing was recommended because no tests changed the outcome. If a patient was diagnosed with lung cancer from an existing screening test, it was already too late. Research proved that getting a chest x-ray every six months in smokers made no difference at all in the outcome of this deadly disease. As a result of this research, screening for lung cancer was not recommended. But recently, it has been shown that a CT scan of the lungs, in appropriate patients, is, in fact, effective in the early detection of lung cancer, and actually can impact the patient’s outcome by allowing for early surgical intervention, for example, or another clinical approach.  Screening tests and recommendations change over time based on new scientific data.

But my goal in this post is to try to show you that getting every imaginable test is not necessarily in a patient’s best interest. Even if wasted dollars were not an issue — and in the US we waste an obscene amount of medical dollars — many tests are just not suitable for screening purposes. They may be “sold” to a patient as being suitable, but many really are not.   In order for a test to qualify as a useful screening test, the problem needs to be common enough that there has to be value in screening for it.  Screening for a very rare disease is statistically apt to yield so many false positive results that the result of a positive test is worse than no test at all. A false positive result says that someone has an abnormality when they do not.  It is a test error. A false positive, it goes without saying, leads to emotional distress, oftentimes unnecessary treatment, and usually even more invasive testing only to find out that there was nothing wrong with the patient in the first place.

Here’s an example of what I’m saying. The incidence of Lyme disease is 31 per 100,000 people in tic-infested states. The ELISA (enzyme-linked immunosorbent assay) test for telltale antibodies turns positive for about 6% of people who do not have the disease. So, statistically speaking, false positives outnumber true positives by a rate of 200:1 in a random sample of testees. (see here).  The false positive rate is even higher in states that do not have a significant infestion of lyme-bearing tics, such as North Carolina. By their very nature, all antibody tests carry a misleadingly high false positive rate, and any interpretation of a single antibody test is fraught with misinformation.  There is always additional testing that is required to diagnose a medical problem based on a single positive antibody test.   In the “it wasn’t so funny at the time” category of anecdotes: When Ruth and I were getting married, we both took the state-required pre-wedding license blood test.  Ruth’s VDRL, the syphilis screening test, came back positive.  No, she didn’t have – and never did have — syphilis, and the second confirmatory blood test showed that her VDRL was indeed a false positive, but it did make for some anxious days waiting for the second round of results.

There are other tests that often give gray answers and are misinterpreted by the ordering physician resulting in the patient getting inaccurate information. Sometimes that occurs from a physician ordering a test that he or she is not qualified to correctly interpret. Antibody testing for allergies (food allergies in particular) have very high false positive rates; as many as 50-60% of positive tests are not related to a food allergy at all (see here).  But antibody testing is a high margin test and gives a yes or no answer when patients demand one. It is frequently the wrong answer, but it is an answer.

There are many tests that are redundant and don’t yield additional information about a particular condition, but are financially profitable for the provider.  Let me give you two examples of a common screening that I see on a regular basis:

Patient #1 is a 55-year old man who smokes and comes to his doctor’s office for his annual physical. His father had a heart attack at age 54.  The doctor orders a total cholesterol and HDL to help assess his risk factors for the development of heart disease.  His total cholesterol is high and his HDL is low.  The patient is counseled about diet, quitting smoking, and prescribed a statin, a cholesterol-lowering medication.

Patient #2 is a 55-year old man who smokes and comes to his doctor’s office for his annual physical. His father had a heart attack at age 54. The doctor orders a total cholesterol and HDL to help assess his risk factors for the development of heart disease.  The doctor also orders apolipoprotein B and apolipoprotein  A  tests, as well as an LDL particle size test, all of which are considered risk factors for the development of cardiovascular disease. These test results come back showing the patient has an increased risk, so the doctor then orders a carotid or femoral artery ultrasound test looking for intimal thickening.  That test looks for an increase in the thickness of the innermost layer of one of the major arteries in the neck or thigh. This is also a known risk factor for the development of future strokes or heart attacks. The patient is counseled about diet, quitting smoking and prescribed a statin, a cholesterol-lowering medication.

Do you see my point? Both patients ended up receiving the exact same medical treatment for their increased risk of developing cardiovascular disease. But there is a difference. From my personal experience, Patient #2 most likely came away awed by the caring, thoroughness, and expertise of his physician, and probably raved about this experience over beer and cigars after a golf game. The patient probably didn’t complain about the high cost of the additional tests that his insurance company most likely covered. Depending on where he is located, these tests added well over $1,000 more to his bill than Patient #1’s bill. From what I have seen, the majority of physicians who order the femoral artery test have financial ownership interests in the ultrasound lab where the test is performed; that is a not insignificant financial incentive that should not come into play in deciding which tests should be performed on a patient.

But let’s look at what experts say about the apolipoprotein tests and the LDL particle size test.  Uptodate.com is a medical resource that is frequently updated and has expert physician panels making evidenced- based data available to recommend diagnostic and treatment options on a large number of medical issues.  It has largely replaced the text books as physicians’ go-to reference source, as Uptodate.com is revised and, well, updated, on a much more frequent basis than text books. (I would bet that your internal medicine or family physician uses Uptodate.com as their primary reference source—ask.) So having qualified the reference, this is the top experts’ latest recommendations for screening blood tests for lipids:   “When a decision is made to screen lipids to assess CV risk, we suggest measuring the total cholesterol and high density lipoprotein cholesterol (HDL-C) rather than a complete lipid profile or other lipid marker or fractions.”

With reference to the apolipoprotein A and B tests, Uptodate.com states, “We agree with the 2010 American College of Cardiology Foundation/American Heart Association guideline for assessment of cardiovascular risk in asymptomatic adults, which does not recommend the use of these tests for cardiovascular risk assessment in asymptomatic adults,” and furthermore, “We do not recommend the routine measurement of LDL particle size or concentration (number), lipoprotein levels, or the use of “ratios.” “

And here is an article about carotid ultrasound screening.  It is effective in showing increased risk for cardiovascular disease, but the test rarely changes treatment plans and would certainly have had no affect at all on the treatment of either of our patients.  See here.

My point from the above example is that patients are often wowed by unnecessary testing as it falsely indicates to the patient a level of thoroughness and care that is simply not a rational conclusion by those measures. And for the physician, it is a big income generator.  Who loses?  We all do, every one of us, with higher costs in insurance premiums as well as taxes to cover the costs of these tests through Medicare and Medicaid.

In 2003, I attended a large medical office all-practice meeting where I heard a presentation about screening for Apo-A and Apo-B abnormalities .  A physician delivered a five-minute clinical presentation on the testing that was unable to clearly indicate a reasonable medical benefit to the patient. But after this brief, insubstantial clinical presentation, there was a twenty-five minute financial presentation, by the practice administrator, delineating the practice income that would be generated if this screening test were regularly ordered by the practice physicians.  It was clear to everyone present that this test produces a financial windfall.  Sadly, I wasn’t shocked to hear these discussions, but I wasn’t happy about it, either.

Without a doubt, there are many screening tests and preventative healthcare measures that have been shown to improve health and prolong life. Everyone who meets the criteria to benefit should be following those screening recommendations.  On the whole, I find that screening tests fall into one of four categories.

  1. Screening tests that have been shown to be effective in either early diagnosis or risk modification of diseases.
  2. Controversial screening tests on which there still isn’t enough conclusive data to know if they should be done, and each individual has to make their own decision, in concert with their physician, on whether or not to get them.
  3. Worthless screening tests that either don’t prevent disease and death, or are more likely to cause worry and instigate further testing with additional risks and no additional benefit. Some people want these tests, along with as many additional tests as they can get.  My only recommendation is that you be clearly informed about what you are getting, and any risks you are taking, before you submit to the tests.
  4. Screening tests that have zero value other than a financial gain for the medical provider.  There are many hucksters out there.  Donate to them if you choose, but don’t expect to recoup any health benefit at all for yourself.

The “fee for service” reimbursement system that the US currently operates under and which I have discussed here numerous times, contributes significantly to the medical costs of the country without a commensurate medical benefit.  Entrepreneurs are innovators who develop businesses and create jobs and wealth.  Frankly, I don’t want my physician to be an entrepreneur selling supplements and weight loss products and cosmetics and, yes, screening tests for everything under the sun. I want her to be a clinician, a diagnostician, a physician. Physicians are paid well enough for their services. Extracting every possible dollar out of each patient’s pocket should not be a physician’s goal, and our healthcare system, contrary to the principles of fee for service medicine, should not encourage this.

A future post will talk about the recommended screenings for adults, and I’ll tackle the controversial question, “Should I get a total body scan?” It’s not pretty, I’ll warn you…

 

 

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