Last week, Mark Cuban, the billionaire businessman (Dallas Mavericks, Landmark Theatres) and reality show celebrity (“Shark Tank”), set off a lively debate on Twitter by dispensing the following health advice to his 2.83 million followers:
1) If you can afford to have your blood tested for everything available, do it quarterly so you have a baseline of your own personal health.
2) Create your own personal health profile and history. It will help you and create a base of knowledge for your children, their children, etc.
3) A big failing of medicine = we wait till we are sick to have our blood tested and compare the results to “comparable demographics.”
Please don’t listen to @mcuban for medical advice. Paging all doctors. https://twitter.com/mcuban/status/583366647987093504 …
If you’re tempted to listen to @mcuban, read/listen to this: Is Preventive Medicine Actually Overtreatment? http://www.npr.org/2011/02/11/133686016/Is-Preventive-Medicine-Actually-Overtreatment …
Doctors did respond — on Twitter and elsewhere — to Ornstein’s call to explain why Cuban’s advice was such a bad idea. So did other medical journalists and health advocates.
A teachable moment
Cuban’s subsequent tweets have made it clear that he remains unconvinced by the evidence-based arguments that shows, as one physician put it, “testing for the sake of testing very bad medicine.”
Still, perhaps the social media firestorm Cuban ignited last week may help some of his millions of followers — or others who stumbled across the debate — to develop a better understanding of why overtesting is not only a waste of scarce medical resources, but also potentially harmful for many of the individuals who undergo the tests.
“Medicine is complex,” writes Ornstein, in his annotated posting of his Twitter debate with Cuban. “Patients should be encouraged to be active participants in their health care. But there’s this belief, and it’s wrong, that screening tests can only help, not hurt. … There are false positives and false negatives. There’s fear that results from an abnormal result (even if it later proves normal) and there’s treatment. And treatment comes with side effects.”
Cuban’s main point paralleled arguments that he’s made — that many people have made — about the need to get as much data as possible, all the time.
You can see that conviction in Cuban’s investment portfolio, too. He’s getting data on pedestrian walking patterns. Data on how people use Twitter. Data on where NBA players are most likely to hit their shots.
In fact, Cuban’s stance seems intuitive: the more data the better, right? Especially for something as important as your health!
But health care data operates under a unique set of rules. For one, the data is often imperfect — and the more data you collect, the more likely you’ll stumble across a misleading indicator, like a false positive.
“Getting lab tests just because you can runs the risk of the same problems that plague screening tests, like the PSA,” Shannon Brownlee told me. (Brownlee’s a senior vice president at the Lown Institute, and the author of the influential book Overtreated: Why Too Much Medicine Is Making Us Sicker.)
“You’re looking at false positives that require a lot of follow up, which involves both worry and risk of physical harm,” Brownlee added.
‘A huge distraction’
Cuban’s main defense appears to be that the backlog of test records will help him and his physicians with medical care in the future, since new test results can be compared to his old results. This is an interesting concept but I’m afraid we are nowhere near the point in the vast majority of situations where this type of comparison would be helpful. For most doctors, this sort of avalanche of earlier tests would prove a huge distraction.
And Cuban doesn’t seem to realize that researchers have devoted an enormous amount of research trying to figure out how to interpret test results. It’s extremely unlikely that an individual doctor or patient will be able to immediately improve on their work in the setting of an occasion where blood test results are actually needed. In any case, even if you accept the value of baseline tests, the idea of obtaining tests every 3 months would still require additional validation. This could well be a textbook definition of TMI.
Trudging across town to a lab every three months to get bled? That’s so 20th century. It’s labor intensive, time consuming, expensive and provides blips of data separated by months of darkness. Cuban said such testing would provide a baseline that would add context to test results obtained when someone is sick. But the signals would be sparse and hard to interpret. Diet, sleep, time of day or the seasons, recent activities or travel and many other factors could bounce the results around. Imagine being sent for a prostate biopsy just because you went on a long bike ride before a PSA test.
You’ll find different parts of this debate all over social media, but a good place to start is with Ornstein’s annotated summary of his Twitter exchange with Cuban, which you’ll find on Storify.