It is the beauty of evidence-based medicine (EBM) that a scientist can at once be a Pope and a Galileo. His transmutation is as effortless as it is discretionary. If you think you’ve met Galileo — a rebel, a free thinker, a rocker of the establishment — the following week he is a Pope, castigating detractors, censoring critics, and celebrating uniformity. He changes by a roll of the dice. His change is decided by a quirk in hypothesis-testing known as statistical significance. If the p-value is 0.051 he is Galileo, if the p-value is 0.049 he becomes the cardinal. He is one day a raging skeptic and another day a true believer.
The latest fight between orthodoxy and free inquiry is about the benefits and harms of statins for primary prevention. A review, and an editorial, in the Lancet said the benefits of statins are real, the harms are exaggerated, and skepticism of benefits of statins should be censored because doubt can harm the public who may not take their statins and thus die prematurely. Stated differently, skepticism kills. The lead author of the review once asked the BMJ to retract a study which he felt overplayed the harms and denied the benefits of statins. The editor compared the fear about statins to fear about vaccination. Statin skeptics, like vaccine deniers, are now medicine’s truthers.
It is unclear what will send the skeptics to the Gulag. Is it a denial that statins have any benefits or a quibble about the precise benefits? Will you be sent to the gulags if you incorrectly say the number needed to treat (NNT) is 150, when it is in fact 100; if you get the confidence interval wrong; or if you underestimate the significance level? The Spanish Inquisitors made it simple — deny Jesus is the son of God, and you’re in the torture chamber. The new truths are probabilistic — God is statistically significant with p-value perched precariously at 0.05.
The BMJ, at the crossfire of this inquisition, responded to Lancet’s accusation in kind. The fight between Britain’s two major medical journals is like the recent spat between the leave and remain camps in Brexit — that there was a winner shouldn’t detract from the pettiness, or the close margin, of the dispute. I shall spare you the granular details of the statin war (excellent summary atCardioBrief and a raucous take by Michel Accad are worth reading). Granularity in EBM is not the same as looking at the night sky through a telescope. You won’t be awed by magnifying the details. However, if you suffer insomnia, the 30-page review of statins in Lancet might be what the doctor ordered.
What are the harms of statins? Aside from remembering to take the pill, which should no longer be burdensome, but a fact of life like wearing a seatbelt or filing taxes, the harms include muscle pain. Muscle pain? Are you thinking what I’m thinking? Muscle pain! BFD! Is modern man, who by now was supposed to have colonized Mars and traveled to Proxima Centauri in search of a new planet, arguing about muscle pain? What an anti-climax!
The dispute doesn’t have the same metaphysical significance as Earth versus the sun at the center of the universe. Galileo’s captors saw in Galileo’s musings the contradictions of their religion. But the contradiction of statins is more divisive than heliocentricity. But let us not falsely elevate the fatigued quadriceps muscle to martyrdom. The statin war is not about skeletal muscle. It is about ossified ideologies. The statin war asks medicine’s most primal question – what is the role of medicine in society?
It is a war between two movements in medicine, which itself has become a religion with the physician as its high priest. Medicine is divided into two sects. One is the less-is-more movement. The other movement, the antithesis of less-is-more, doesn’t have a name, but I will call it the “unlimited medicine” movement. One emphasizes medicine’s limitations, the other medicine’s possibilities. One is short-sighted, the other can stare only at the horizon. One is too willing to press the brake, the other ever eager to press the accelerator. One seeks redemption in data; the other seeks salvation in venture capitalists. One wants to be guarded by budgets and opportunity costs, the other wants to break chronological budgets. One sees man as mortal, the other dreams of transient, incremental, immortality.
The two movements are profoundly similar. The men who fought for Richard the 1st and Saladin in Jerusalem in the Crusades, though fought against each other, all thought they had God on their side. Both the less-is-more and unlimited medicine movements believe they have history on their side. Both movements are sincere, overly sincere, yet disingenuous; both can be dogmatic, both are sentimental, both are self-righteous. Both are right, neither is wrong, yet both are wrong.
The less-is-more movement is at least forthright in its objectives. It believes medicine is doing too much. It believes medicine is overtesting, overtreating, overdiagnosing, overstepping, and over intruding in the lives of private citizens. It believes medicine has lost its moral compass. Just like a nosey mother-in-law extracts too much for the occasional babysitting, medicine extracts too much for extending longevity by too little
On the face, the less-is-more movement is the more ideological and self-righteous of the two. This movement has made two strategic errors. It has erred by ascribing to malice what can be ascribed to chance. It believes, implicitly, that doctors do too much because of greed supported by the incentive structure. This naïve reductionism, which can easily be countered, has alienated many doctors. This is a double blow for the movement which has lost not only its key message but supporters of that message. The movement should, instead, have emphasized that medicine is an art, an imperfect art; that the art is minimalism, and minimalism needs judgment and skill; that the art is not uniform and can vary between its practitioners, but that’s ok; that the art can be ruined by diagnostic and therapeutic incontinence. It has not done so because it does not believe medicine is an art but a precise scientific enterprise. It is this belief which is the root of its second, more fatal error.
The movement believes its core principles can be justified by science, that minimalism is scientific.
Evidence based medicine (EBM)is the oddest of odd sciences.
It is not a science of precision but a science which specifies trade-offs. You win some, and you lose some, and EBM, when done right, tells you how much you win and how much you lose. EBM quantifies trade-offs. EBM doesn’t abolish trade-offs. The less-is-more movement doesn’t acknowledge trade-offs. It fails to acknowledge that therapeutic incontinence saves a few, very few to be precise, but few nonetheless. It denies that overuse of CT for pulmonary embolism, for example, saves a few lives from fatal pulmonary embolism who would have escaped the net if medicine were practiced as a fine art. It cannot get itself to say “we overtest and overtreat and yes we help a few, but it’s not worth it.”
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