Medical Necessity vs Therapeutic Fashion: How Evidence-Based Is Your Field of Medicine?

John M. Mandrola, MD


July 18, 2022

I've been thinking a lot about how the standard of care in medicine is established and then becomes resistant to critical appraisal.  

These were not happy thoughts. I've come to believe that too often therapeutic fashion trumps medical evidence. Once it reaches a threshold, anyone who dares question it based on the evidence is considered a loon or a nihilist.

My point in what follows—beyond expressing frustration—is to induce people to consider how and why medical norms become established. And to consider the fashion of the day with a historical frame, recalling that we used to use hormone replacement therapy to prevent heart disease in postmenopausal women.

Coronary Stents in Patients With Stable Disease

A friend of mine who is an interventional cardiologist told me the story of a middle-aged man with a severe narrowing in his right coronary artery. He had undergone a test for coronary artery calcium score that was abnormal. (I've written against doing these tests, but that is for another post.) This man exercised without limitations or symptoms. The abnormal calcium score led to a stress test, even though the guidelines say the test is to guide statin decisions. The result of the stress test was positive, and his doctor sent him for a cardiac catheterization.

There is nothing unusual about this cascade. It is the therapeutic fashion.

My friend recommended against implanting a stent. He essentially said, "Sir, you have a narrowing, it is stable, and we will treat it medically with statins and other meds." This is what the evidence shows, including the most recent ISCHEMIA trial.

But everyone went nuts. The family was upset, and the referring doctor was aghast. The patient went to another interventionalist and got his stent.

My friend went against the therapeutic fashion. Will he do it again? How many families and referring docs can a consultant afford to upset by following the evidence?

Left Atrial Appendage Occlusion for the Prevention of Stroke

The theory that percutaneous left atrial appendage occlusion with a device would reduce stroke is plausible. Yet the evidence is extremely dubious. I've written about the evidence and posted my lecture arguing against this procedure.

Yet the US Food and Drug Administration approved the device, and the therapeutic fashion has now normalized a preventive procedure with a major complication rate of at least 5%. Patients are being told you don't have to take anticoagulants; you can have a device instead. And advertisements have intensified interest among patients.

I've debated this topic on five continents and have written about it in columns and journal articles. The therapeutic fashion has won.

I am now akin to my interventional friend—an outlier, a nonbeliever.  

Lytic Drugs for Stroke

If you present to an emergency department with an acute stroke, there is a good chance you will receive a thrombolytic drug. There is also a decent chance that your emergency medicine doctor doesn't believe it works.

But neurologists believe it works, and hospitals have "stroke centers" based largely on using said drugs. The therapeutic fashion is that lytics should be used in acute stroke.

Yet the evidence is hardly clear. In 2018, I argued against the use of thrombolytic therapy for acute stroke. The emergency medicine literature is replete with critical appraisal of this practice. And a recent review—from a neurologist—suggested that baseline differences in the seminal National Institute of Neurological Disorders and Stroke (NINDs) trial occurred because of randomization errors. The safety/efficacy balance is a major issue because lytic therapy increases the odds of devasting bleeding in the brain.

Yet anyone who expresses the view that we ought to repeat the NINDs trial is considered a fool.

Other Notables: There Are Many More

Therapeutic fashion now awards sacubitril/valsartan the mantle of "best" renin-angiotensin inhibitor for heart failure. But its only clearly positive trial came against enalapril.

Electrophysiologists accept that atrial fibrillation (AF) ablation improves symptoms from AF, but it has never passed muster against a sham procedure.

In the intensive care unit, we cooled patients after cardiac arrest for years. It took not one but two trials to break the sclerosis of that thinking.

The Dangers of Therapeutic Fashion

CAST, a trial published in 1991, found that the therapeutic fashion of suppressing premature ventricular contractions after myocardial infarction (MI) with antiarrhythmic drugs led to a more than doubling of death in the drug arm. This finding shocked the cardiology world  because it shredded an ensconced practice.

I encourage you to read this account from British cardiologist John Hampton who tried to publish a small trial documenting higher mortality in post-MI patients treated with antiarrhythmic drugs 10 years before CAST. No journal would publish it—until after CAST had changed the fashion of the day.

Given that the number needed to kill in CAST was approximately 29, how many lives would have been saved without such attachment to a therapeutic fashion?

What Causes Therapeutic Fashion

Fixing the problem means considering the causes.

In many cases, especially  the search for ischemia, profit motive clearly plays a major role. But there is also the fear of missing out. If colleagues have accepted a procedure, and other hospitals are not only doing it but marketing it, then a doctor who does not do the procedure may feel inadequate—a lesser specialist.  Never discount human nature in the cause of therapeutic fashion.

Doctors also have a strong inclination to want to do something. I sense that many neurologists and cardiologists simply want to help their patients. Not intervening with lytics or stents seems impotent.

Look Inward…

I hope that clinicians in other fields consider their own therapeutic fashions. How secure is the evidence? How foolish will it look with the sharp eye of history?

While medical advances will render many of our practices archaic, which is expected, the question I propose is: Would stronger and more neutral critical appraisal of our therapeutic fashions reveal now what future generations will surely come to know?


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.