Aug 20 2012

Nocebo Nonsense

You have probably had the experience of having a heated conversation with one or more other people and after things calm down and you are comparing notes you find that everyone has a different memory of the conversation that just happened. Of course, you are certain that your memory is the one that’s correct.

Likewise, different people can look at the same set of information and come to radically different interpretations. That’s because we all have narratives inside our head – worldviews and ways in which we model and make sense of the world.  We are very clever and creative at incorporating new information into our existing narratives.

I was reminded of this when reading a recent article by Deepak Chopra on the nocebo effect. Nocebo effects are similar to placebos effect except they are negative – unwanted side effects that are reported from taking inactive placebos. Chopra clearly has a narrative that he is working from, one that is very different from my own. He is steeped in, and in fact is partly the architect of, various “alternative medicine” narratives.

I, of course, am working from very different narratives – skeptical ones. I do think, however, that not all narratives are equivalent (that would be a post-modernist position). Some are more logically consistent and evidence-based than others. Further, the job of a journalist or intellectual is to look past existing narratives (especially their own) and ask the hard questions: what does the data actually show, how does my perspective bias the story I am telling, and are there any other points of view that deserve attention? When the topic is anything that intersects science, then a proper interpretation of the scientific evidence is what should hold sway, and should trump any existing narratives.

Chopra doesn’t do this. Rather, he dives into his existing narratives with gusto and complete disregard for the actual evidence. He begins:

For decades the placebo effect has existed basically as a nuisance, so far as the medical profession is concerned. Some people benefit from being given a sugar pill instead of an actual drug. This remarkable result cannot be marketed, however. It doesn’t fall within the ethics of medicine to prescribe fake drugs. Therefore, a doctor in practice, whose training has drummed into him that “real” medicine means drugs and surgery, will shrug off the placebo effect as psychosomatic, or “it’s all in your head.”

The alternative guru narrative is in full display: doctors only know drugs and surgery, they are concerned with what is marketable, and they are dismissive of anything psychological (spiritual). The only statement above that I would consider fair is that it is unethical to prescribe fake drugs – it is. But that doesn’t mean you cannot optimize the patient interaction to maximize non-specific therapeutic benefits (certain useful aspects of placebo effects) within the confines of ethics.

I covered placebo effects and the ethics of placebo medicine here, here, and here – so take a look for a detailed discussion. Bottom line – there are many placebo effects, most of which are just statistical effects or subjective reporting. There does not appear to be a significant biological placebo effect, and placebo effects are not dependent upon positive expectation. Any placebo effects worth having can be obtained while practicing real science-based medicine, simply through a positive interaction, and does not require deception or belief in magic. To emphasize an important point, relevant to Chopra’s  placebo narrative – placebo effects are largely subjective, without objective improvement. A recent study by Kaptchuk comparing different placebos and real treatment for asthma found just that – improvements from placebos were subjective only, without any objective improvement.

But Chopra’s narrative is that the mind is everything. It is all powerful and is the real master of health and illness. So he writes:

The placebo effect is real medicine, because it triggers the body’s healing system. One could argue that this is the best medicine, in fact, since: a. drugs do not trigger the healing system and b. the placebo effect has no side effects. Staying well means that the body is taking care of itself – and you – through a feedback loop of chemical messages.

Funny – I never learned about the “healing system” in medical school. Oh, that’s right, because I am a Western doctor who only knows about drugs and surgery. They must have edited the “healing system” out of my anatomy and physiology textbooks. Sarcasm aside, the body certainly has mechanisms for healing and repair. Bones can knit together, cuts can close back up, and we do have an immune system that vigilantly protects our bodies against infection and cleans up any dead or diseased tissue. For some reason I don’t think this is what Chopra is talking about.

Generally speaking, chronic illnesses occur because one or more of the body’s systems are failing. Perhaps there is a genetic abnormality or predisposition, or trauma or some other disease has simply overwhelmed our body’s repair and maintenance systems, or age has simply taken its toll. The “alternative medicine” narrative, however, is that the body has this mysterious, sometimes described as energy-based, “healing system” that can heal all ills. All you have to do is activate it. The healing system, therefore, can be triggered – by whatever the guru is selling.  This is a wonderfully marketable narrative.

This would be great if it were true. I wish the body had unlimited healing ability. The evidence, however, simply does not show this. Specifically, the vast literature on placebo effects does not show that they trigger any objective “healing” or physiological effect. They generally improve the reporting of subjective symptoms only.

Interestingly, Chopra says above that placebos have no side effects, but then the rest of the article is about the nocebo effect – which are side effects from placebos. D’oh. Chopra is only interested in promoting his pre-existing narrative – the mind is all-powerful. Positive thoughts cause healing, while negative thoughts cause illness. So if you are sick, it’s all your fault, due to your negative thoughts. This is standard Indian philosophy – consciousness is a real thing and the physical world is just a manifestation of consciousness.

Chopra’s article was inspired by a New York Times article by researchers into nocebo effects. The researchers, however, make very different points from Chopra. They review the scientific evidence, which is pretty clear. People will report negative side effects even when taking placebos. If they are warned about a particular side effect, they are more likely to report that one. Again – there is no reason to think this is anything other than subjective reporting. Stress is the one factor that can cause real physiological consequences, and therefore illnesses that significantly respond to stress (like heart disease) can be affected by anxiety or hopefulness. This is not true, however, of most diseases.

The researchers write:

The nocebo effect can be observed even when people take real, non-placebo drugs. When medical professionals inform patients of possible side effects, the risk of experiencing those side effects can increase.

That is a perfectly reasonable point – doctors need to think about how they tell patients things. Of course, we do, but some more than others, and there is always room for improvement. The authors suggest, for example, that (within the confines of honesty and informed consent) doctors focus on the positive rather than negative aspects of a procedure. I have heard this referred to as “verbal anaesthesia.” This is, of course, one aspect of old-fashioned good bedside manner.

We can, however, get caught up in the mechanics of modern medicine and the need for informed consent. There are times I have to discuss potential negative aspects of a treatment because they are essentially mandated by the FDA. I know that doing so will increase the likelihood of my patient reporting a negative side effect (nocebo effect). It would be much easier if I could just lie to them, tell them only what they want to hear, and justify this action as maximizing the placebo effect of the procedure. But that is not the ethics of medicine (only alternative medicine practitioners can do that).

There is a nuance to communicating to patients to meet, as best as possible, these conflicting goals of informed consent with maintaining a positive outlook. That, I think, is the proper lesson to take away from this data, as the researchers themselves suggest.

Chopra, however, has a different narrative. He is selling (very successfully) the notion that consciousness is everything, and your thoughts are your destiny. Placebo and nocebo effects, regardless of what the scientific evidence actually says, are just another way to support this narrative.

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