Monday, February 18, 2013

Different Rules Apply: Ayurvedic Medicine's Self Defense

Recently I was doing some reading on Ayurvedic medicine,* which is India's traditional medicine, with foundational texts dating back to the early Common Era. I know very little about it and was reading out of curiosity.  Plus, if there's anything evidence-based I can incorporate into my fund of medical knowledge, I'm happy to do so. (A major resource is the NCCAM site, which has links to meta-analyses.)  After a day of web-surfing obviously I'm not an expert, and this post is not meant as a summary or a global indictment of Ayurvedic medicine. Rather it's to point out the patterns that appear in evidence-avoiders of all stripes. In what I've seen so far, two defenses of Ayurveda repeatedly appeared:


1) An appeal to Ancient Wisdom(tm) - a classic argument from authority. Many of these resources read more like history texts than medical articles. (The history is indeed fascinating, but that doesn't mean the things they were saying were true.)

2) Occasional mentions of how some aspect of Ayurvedic medicine is borne out in an experiment or clinical trial.

A good example of #2 is reserpine, a drug which was successfully used for quite a while over the last few decades to treat psychosis and hypertension, but which has recently been supplanted by better ones. It was isolated from snakeroot, which had long been used in India to treat insanity. Through the process of reverse pharmacology - taking something that was already being used in the clinic, and reverse engineering it - we were able to get a more consistent pharmaceutical and important new information about human biology.

The reason I posted this is that the patterns of evidence avoiders of every stripe become very obvious when you've seen them enough, and much of what I found about Ayurveda provides a concrete example in a new setting. If you're reading this blog then I probably don't have to explain why consistently reverting to #1 above is not a good sign for any enterprise. (No one cares that it's 5,000 years old and your grandfather does it! Does it work!?!?!? Imagine if you were waiting for your cardiologist in her office, and opened one of her textbooks to discover that it was mostly biographies of earlier cardiologists, and she told you to have a certain procedure done because you shouldn't question what people have been doing for a century. Yikes!)

But #2 is to me the most damning, for someone who argues that Ayurveda should be considered a separate body of knowledge with its own "way of knowing".  If your main selling point is that the methods of the modern evidence-based version of your profession bear out bits and pieces of your folklore-based one, isn't that a little embarrassing? Why not just embrace the evidence and incorporate those parts of other practices that the evidence bears out? (Which is a good place to repeat: you know what they call alternative medicine that works? Medicine.) If you're a fan of Ayurvedic medicine, you should be clamoring for more rigorous studies of these treatments, to apply the same standard of evidence to everything, rather than asking for special exemptions. (And to their credit, some people do this, Ashok Vaidya among them in his reverse pharmacology work.) Throw out the parts that don't work, and focus on what does.  Evidence-based medicine works, and continues to improve precisely because of this approach.  It's not perfect and still not as evidence-based as it should be, but the trend is positive - this is why people cared about meta-analyses like the one by John Ioannidis.  (Can you find similar constructive criticisms of any form of alternative medicine by its practitioners?)


My own suspicion is that the information in the collective wisdom of traditional medicine from all over the world is mostly nonsense, but that it's probably still better than random chance, and that we don't know which is nonsense and which part works until we apply the same standards of evidence to everything. To this end, in ethnobotany, there's a great project at the University of Michigan Dearborn to catalog and preserve Native American ethnobotanical information so it's not lost to history, and a lot of the information is medical. By all means, let's see if it works! But avoiding the application of the same standard to yourself is a strong signal. At the very least, you're then behaving the same way a charlatan behaves. The way this usually comes to skeptics' ears: "But there are other ways of knowing things." In other words: "I can't prove it, but you should still do or agree with what I say." An additional red flag is painting the evidence-based practitioners as immoral or conspiratorial. (Starting to remind you of, I don't know, creationists? Truthers?) The us-vs-them narrative where individuals define themselves in opposition to the majority as a persecuted minority is often very clear. A great example is to be found here: "My point in this article, is getting the western allopathic medicine to work in harmony with, and stop suppressing, the alternate healing techniques that are available, and stop selling this oppressive culture of dependence on doctors, hospitals and drugs."

I mostly wanted to point out the similarities across non-evidence based philosophies when they're forced to compete in the open with a parallel evidence-based philosophy. But since the concrete example here is a type of alternative medicine, I wanted to list a few more observations specific to that realm.

- The us-vs-them narrative in various forms of alternative medicine often takes on the flavor of oppressive Western philosophy vs everyone else.  This is particularly frustrating, because apparently these people haven't been paying attention to the course of science over the last few decades.  Science and medicine are no longer Eurocentric endeavors, and would not exist in their present forms without the major contributions of non-Western researchers.  The respected scientists and physicians in Japan and China and India and Korea and lots of other countries would surely be surprised to learn that they are being oppressed by Western culture.  Quick, alternative practitioners, go tell them and save them!

 - There is a defense of alternative medicine that admits that its successes are largely placebo effect, but that placebo effect is a valid treatment so this is acceptable.  That's a very slippery slope. I would love to be able to treat people by making something up and having them feel better, but can I morally take their money for that? When I've asked pro-placebo people this they've been uncomfortable with the idea, which shows that this argument hinges on whether I made it up, or some guy three thousand years ago made it up.  That's a curious basis for morality.

- I've had the unpleasant experience of talking with several otherwise brilliant Chinese researchers and friends who manage to suspend critical judgment where Chinese traditional medicine is concerned.  Yes, humans are often guilty of being blinded by patriotism, but these are friends and colleagues who I hold to high standards.  In one case as a test I asked the person about my own grandmother's Pennsylvania Dutch remedies and found out that they were completely unscientific.  (Surprise!)


I'll close by linking back to a post I wrote about getting acupuncture.  I'm an acupuncture skeptic, and trying to be a good skeptic, I had a treatment because of, and not despite, that very reason.  And nothing happened.  But I put my money where my mouth is.  You can't evaluate a new drug with a single dose in one person, so based on my N=1 experience with acupuncture, I couldn't say it did or didn't work.  There are meta-analyses for that.

*If you think I'm misunderstanding something or overlooked important evidence of Ayurveda's effectiveness, please do leave a comment, and I will be happy to consider it.

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