The Placebo Effect (December 2, 2014)
As you have probably noticed by now, the world is crawling with people who feel equipped to lecture others on subjects with which they themselves have no real acquaintance. Every teacher – and parent – has had that experience, as has every chiropractor and acupuncturist, and pretty much every one of our patients. It’s disheartening to be loftily informed by someone with whom we have just happily shared our health success story that “it’s just the placebo effect [smirk]”. This despite the scads of well-publicized research in the past few years on how well spinal manipulation and Chinese medicine work. So, since there’s nothing you can do directly about that moron whom you work with or who is married to one of your relatives, it’s probably worth while knowing something about placebos.
A placebo is a treatment that is known not to work, but is given anyway in an attempt to fool the sufferer into getting better. Now, if tricking someone into getting better with a fake treatment sounds unethical to you, it’s probably because it is. Despite this, about half of medical doctors admit to having prescribed a placebo at one time or another, most commonly aspirin or vitamins but also antibiotics and sedatives. (Great way to keep your patients from looking for something that might actually work for them, guys.) The placebo effect is what has occurred when this useless treatment somehow works.
Most people think “placebo effect” means that you are imagining that you’re better. Not at all. Changes in blood pressure, shrinking of tumors, warts drying up and falling off, airways dilating, inflammation measurably decreasing, and all kinds of hormonal and neurotransmitter changes have been documented to result from placebos. What’s happening in the placebo effect is that your mind, through the medium of your brain, is producing physiological changes. That is a far cry from imagining you feel better. The brain directly controls an enormous number of functions and indirectly influences all of them. Therefore how we think about something has everything to do with how that thing affects us. We all know that stress causes no end of physical problems – it’s not a big jump to consider that our minds might be able to make us well as well as ill.
Understanding the placebo effect is worthwhile as a study because of the insight it gives us into human psychology. And it's not a bad thing for us to be aware of different ways that we can be fooled into thinking that we’re getting better when we really aren’t. Every medical intervention has a mental and emotional effect on the person who is receiving it, and thus some placebo effect is present any time someone undertakes any activity to get better regardless of the actual efficacy of the treatment. A little self-insight can be very handy in that department.
Because by definition a placebo is an ineffective treatment, any improvements that can be seen due to one result from the patient’s thoughts and feelings about it that then cue their brain to produce measurable physiological effects. When you scrutinize it a little more closely, it turns out that the placebo effect actually consists of several different (although related) aspects.
Expectations. Expectation of pain relief causes changes in activity in the brain's opioid receptors (which receive endorphins) and the areas related to pain response and pain processing. And the same inactive substance can increase the pulse and blood pressure or put the patient to sleep -- depending on what the patient thinks it is supposed to do.
Belief. The more strongly someone believes that a treatment will work, the more likely there is to be a beneficial result. This is where doctor input plays an important role. A doctor who really believes in a treatment (“this has fixed everyone with your problem so far”) – or who doesn’t (“you’re going to go see a WHAT?") – very easily influences a patient in the same direction.
Conditioning. When you decide to go to a doctor, every association you have with doctors and the medical establishment comes into play and affects your future health or lack of same. Additionally, the type of treatment (the more dramatic it is, the better it works), the cost (more expensive treatments work better) and even the physical appearance of pills (brightly colored ones are more effective) have all been shown to play a part.
Motivation. How motivated a patient is to get better has an enormous influence on whether s/he actually gets better. Someone who walks into my office who has already made big changes in their lifestyle to improve their condition is practically guaranteed to see at least some benefits, no matter what the actual problem is.
If I haven’t made this clear before, I want to do so now -- although placebos work through the mind, the changes that result are real. Something is not imaginary simply because it is produced by the brain.
Of course sometimes people DO think they are better from a treatment when they really are not. It happens that that isn't the case, however, with joint manipulation and acupuncture. Spinal adjustment relaxes muscle spasm and increases blood flow and range of motion, among other effects, and the physiological basis for how it works to relieve pain and increase function is better understood all the time. As for acupuncture, the points used for needling tend to be located near major nerve plexuses and blood vessels and it generally produce similar effects. I hope to discuss the mechanics of how acupuncture is known to work soon. But in the meantime, rest assured that you actually do feel better because of measurable changes that these therapies have made in your body, and don’t take any guff from idiots who probably can’t even spell “placebo”.
--dr. diane holmes
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