On Harm

Abstract: My take on the perils of of trying to heal and how we harm in the process.

And a plea to my fellow clinicians. We've gotta do better, team.

"Primum non nocere" -- first, do no harm -- gets a lot of press in lay circles. Per the dictum sometimes attributed to Hippocrates, physicians are supposed to prioritize minimizing harm to patients above all else. It is notable that this dictum does not actually appear in most oaths that US physicians recite. The one I recited does not even mention the word "harm."

While I do not put much weight in oaths, it is striking that this canonical part of the Hippocratic tradition has been dropped in an era where medical errors are purportedly killing tens and hundreds of thousands ofAmericans every year.

A Systematic Blindness

More striking to me, though, is what I have observed watching US physicians up close for many years. I believe there is a systematic, unconscious under-appreciation and under-estimation of the harm that we as physicians inflict upon our patients. For reasons too many to enumerate here, doctors are partially blind to the sufferingo ur patients endure as a result of our influence on them.

I believe that the idea that we might even strive not to harm our patients is a fool's errand. We begin harmingour patients before we ever meet them.

The Harm Before the Visit

Consider a definition of harm broad enough to include taking time off work, travel, financial cost, worry, and feeling demeaned. With such a definition, it becomes clear to anyone who has had much interaction with any healthcare system that the harm starts early and is usually ongoing throughout. Most visits occur during work hours, cost money, are anxiety-inducing, and the forms... They also frequently start late and are unpredictable in duration, making scheduling more challenging and burdensome still.

Most of that happens before the physician ever meets the patient.

In the Encounter

Once they do meet, the physician enters a minefield of potential harms. The patient may be quite uncomfortable with the provider, feel judged, feel demeaned, feel that their needs are not being addressed. They may haveprior traumatic experience recapitulated and feel the ripples of that trigger for days, weeks, or months. Even a physician closely attuned to these possibilities may be wholly unaware of some of their impacts.

And this is all before the physician has "done anything."

The Harm of Doing

This is where things get especially messy. We as physicians love doing things. The vast majority of us entered this profession to help people, and when someone comes to us with a problem for which we have a solution, fewthings satisfy us more. Since most physicians have a relatively limited arsenal of tools at their immediate disposal, we tend to rely heavily on the ones we know and have access to -- which varies widely by specialty and by individual.

The problem with doing things, though, is that most anything that does much of anything does both good and bad things. Literally everything has side effects. If we again consider harm broadly, all interventions incur some harm. Even the best sugar pill costs money and requires swallowing something on a regular basis -- it might even cause nausea.

With every intervention, then, we must weigh harms against benefits. We must hold the potential harms of an intervention on one side of a mental scale and the potential therapeutic benefit on the other, then decide which prevails.

The Weighing Problem

This exercise is infinitely easier described than done. If we are lucky, we may have a halfway decent idea of how likely a medicine is to work for a particular person and roughly by how much. We can calculate NNTs and effect sizes and get a rough measure of the benefit side. The harm side, though, is considerably trickier.

It is extremely difficult to know how to compare harms and benefits at all. Is a NNH for new-onset diabetes of53--67 worth a NNT of 217 for a nonfatal myocardial infarction? How do we even compare these? And for any intervention, there tend to be almost countless potential sources of harm, many either rare or largely benign. How, then, are we to sum these and load the harm side of the scale?

Why Harm Is Harder to Measure

There are more fundamental reasons the harm side remains so uncertain. Harm is inherently more difficult tomeasure than benefit. When testing an intervention for a given condition, we have relatively clear, measurabletargets that tend to show change rapidly after initiation -- even when the intervention does not work.

Harm is considerably more nebulous. Harms can frequently be imperceptible, rare, delayed, ambiguous, unexpected,present across all study arms, or any combination of these. This is before accounting for the perverseincentives many researchers face to exaggerate benefit and minimize harm. No matter how carefully we study it, unforeseen harms will remain.

This leaves us with an irrevocably uncertain mass on the harm side of the scale -- one we know is almost certainly larger than we think. Comparing it to our slightly more certain benefit side requires extraordinary care.

The mass of neither harm nor benefit will ever be known with any meaningful precision, and the weighing of each will be idiosyncratic to every individual and every therapeutic encounter. This is much of where the art of medicine resides -- these calculations are profoundly complicated and grounded largely in individual values and intuition. Our commitment as healers and lifelong learners must be to hone that intuition and align it as faithfully as we can with the reality of the world and the values of our patients.

So, What to Do?

We have to try our damndest to make the benefits of meeting with us outweigh the harms, and to acknowledge and mitigate whatever harms we can.