Most people have medical lab work done when their doctor prescribes it. But what if you could have blood or urine analyzed simply by showing up at a lab that serves retail consumers? Is that a good idea?
LabCorp is one of the country’s largest providers of outpatient laboratory services, and it’s planning to allow anyone to drop in without having to visit a doctor first.
Dr. Roy Benaroch, a pediatrician, has mixed feelings about this direct-to-consumer opportunity. Writing on KevinMD.com, he said that although, “there are some tests that seem reasonable for people to do on their own – pregnancy and HIV tests come to mind – others may lead to problems. … People imagine tests are simple things that give you a reliable, yes or no answer. In reality, many tests are far from perfect. And their results might be more misleading than accurate.”
We agree with Benaroch’s reasoning even if we don’t love the patronizing flourish – sure, many people expect a lab test result to paint a complete picture of their situation (like a pregnancy test), but to presume that they’re incapable of understanding that a numerical value often offers only a guideline and not a definition is patronizing.
These days, people can get an accurate result from a drug store urine pregnancy or saliva HIV test if it’s timed it properly. But finding out what’s going on from lots of other kinds of tests is a lot more complicated. In those situations, it’s not just “buyer beware,” it’s “buyer be informed.”
For example, Benaroch noted that there are many kinds of thyroid function tests, but thyroid antibodies often are positive in people who don’t have thyroid disease. A test for lupus, known widely as ANA (antinuclear antibodies) often is positive in people who don’t have that chronic inflammatory disorder, which is caused by an immune dysfunction.
And don’t get Benaroch started on blood tests for allergies. “A recent study,” he wrote, “showed that even among those with a positive food allergy blood test, only 2.2% actually had a food allergy. If you do big panels of food allergy tests, at least some of them are going to be positive in anyone – that’s just the nature of that kind of test. That’s why allergy testing is such a bad idea, unless there’s a specific clinical indication.”
Not all lab tests, of course, are directed toward a diagnosis of something wrong or concerning; some are done for screening purposes. Benaroch maps somes tricky terrain there, too, if consumers have them done without reasonable medical intervention.
The prostate specific antigen (PSA) test is used to screen for prostate cancer, but a lot of men get positive results when they don’t have cancer or have cancer that will never prove threatening. That is, they’ll die of something else long before the prostate cancer become problematic. Of course, some prostate cancers should be treated, some aggressively, but, as Benaroch said, “appropriate screening for it involves more than just getting a blood test.”
A few other real problems that have gained a sort of “trendy” testing popularity could enter into this equation – celiac disease and Epstein-Barr virus, among them. About 1 in 100 people are affected by celiac disease, another immune disorder in which the body cannot process gluten, a certain kind of protein. Definitive testing for celiac disease is complicated, and most of the people who test positive will never develop celiac. “In other words,” Benaroch explained, “a negative tells you something (you’re unlikely to ever get celiac), but a positive tells you nothing (you may or may not currently have celiac, and you may or may not ever develop it.)”
The Epstein-Barr virus is a type of herpes virus well known for causing infectious mononucleosis. Some people appear to suffer from it chronically, with severe fatigue as its signature symptom. It has been misunderstood by both medical professionals and patients, and Benaroch is right to wonder if LabCorp can or will explain sufficiently to consumers what their possible Epstein-Barr results mean.
And don’t forget that labs, like any other medical provider, make mistakes. Any concerning lab result a consumer receives independent of medical analysis should be investigated, and probably repeated.
Then there’s the profit motive. Apart from any useful information or guidance in diagnosis and treatment of problems that can puzzle even trained scientists, what else do publicly available labs offer to patients except a convenient way to separate them from their money?
Unless doctors have a financial stake in a lab to which they refers patients, they don’t have a conflict of interest in prescribing a test. But, as Benaroch questioned, “Once LabCorp is profiting off more and more tests, won’t the logical next step be to market them more heavily?
It’s already happening, in my neighborhood, especially with allergy testing – LabCorp really wants me to order more. What happens when they skip me and market straight to you?”
Pharmaceutical companies now do so with their drug marketing. What’s to stop LabCorp, and any other such businesses that begin reaching out to you and me directly, from claiming that access to their services help people stay healthier? See our blog about providers who promote consumer screenings not just for health reasons, but to juice profits.
Still, maybe some such claims about better health through lab tests could be true. Especially if patients do enough objective research about what they want to know and the best ways to find out if it pertains to them. Especially if they understand all the motives a lab has in issuing the invitation to be tested, and the complications that numerical results can have.
But, honestly, most people won’t go to the considerable lengths they should to improve their chances of getting good, useful information from a lab test. Don’t engage in lab tests unless you know what you’re doing, and why.