#Respectful Insolence » Feed Respectful Insolence » Comments Feed Respectful Insolence » The “myth” of placebo effects Comments Feed R.I.P., Seán Ó’Laighin Autism prevalence is reported to be 1 in 50, and the antivaccine movement goes wild…again -- Respectful Insolence The “myth” of placebo effects Posted by Orac on March 21, 2013 -- Yesterday, Stevenson provided yet another in her long line of teachable moments in the form of a post entitled, Busting the Placebo Myth: Placebos Don’t Cure. In it, she rails against us nasty, pointy-headed skeptics who point out that placebos only make people think they feel beter and don’t actually make people better. The hilarious thing is that she uses studies that I’ve blogged before in order to come to -- promise. Clearly, Stevenson is really, really peeved at the criticism of her quackery that labels it as “placebo medicine.” Of course, as I’ve discussed time and time again the vast majority of so-called “complementary and alternative medicine” (CAM) or, as it’s called now, “integrative medicine,” is based on placebo medicine and the idea that wishing makes it so. I realize that Stevenson doesn’t like that, but that’s just tough. Reality is reality, quacks are quacks, and science -- One of the most frequent epithets tossed at people who make claims of alternative medicine is that it’s just the placebo effect. But that is based on the myth that placebos can cure. The reality, as clearly documented by science, is that they don’t. So the skeptics base their favorite claim on a myth, not reality, and most assuredly -- Stevenson then goes on a brief rant about what she refers to as the “myth” of placebos, including that placebos don’t heal, that placebos are a “complete flop,” that no one is ever “cured” by a placebo. Of course, these are not myths. They are more or less true, except for the second one. Even skeptics don’t say that placebos area a “complete flop.” we’re all for studying placebo effects and determining ways to maximize it during treatment with actual…oh, you know…effective medicine. What we don’t approve of is relying on placebo effects alone, which is what the vast majority of CAM is. Not only is it unethical to lie to patients that way, but it doesn’t help the pathophysiology of the condition being treated. To most ethical, science-based physicians, that’s a double whammy against using placebos that can’t be overcome. The first funny thing is that, in order to make her point, Stevenson in essence buys into this point. Rather than trying to argue for the “pwoerful placebo,” some like to put it, or The Secret, as I like to put it, she actually does her best to rubbish placebo effects as insignificant as an introduction to arguing that any condistions “cured” by alternative medicine couldn’t possibly have been cured by placebo effects. This is a straw man even bigger than the aforementioned straw man whose demolition with napalm-grade flaming stupid could be seen from space. That straw man is that skeptics dismiss “healing” by alternative practitioenrs as being due to placebo effects. -- The study used FEV1, Forced Expiratory Volume in 1 Second, to measure effectiveness. The graph on the left clearly shows that the drug placebo and sham acupuncture (another kind of placebo) had no curative effect, as they didn’t cause any change in FEV1. However, in the graph on the right, you can see that the subjects felt that both the drug placebo and sham acupuncture were nearly as effective as the actual drug, albuterol. Two things are clearly demonstrated. One is that a patient’s sense of well-being can readily be skewed by belief. The other, though, is that placebos have absolutely no healing benefit. It kind of creeps me out that that’s more or less what I concluded in my analysis of this particular study. She also discussed the infamous “placebos without deception” study by Kaptchuk that was sold as evidence that you don’t have to lie to patients in order to invoke placebo effects but, when examined more closely, shoed nothing of the sort. For a moment, I was wondering if I was losing my sanity. What kept me from getting too worried was the tone of the article, very -- be a payoff, and I wasn’t wrong: The claims by skeptics that the placebo effect can explain away any and all results of alternative medicine are pure bunk. They’re based on a false belief, the idea that the placebo effect is so powerful that it can cure. That is nothing but a myth. They can palliate—make people feel better—but never cure. The placebo effect can be powerful in terms of people’s sense of health and welfare. However, no one is ever healed by a placebo. Therefore, when someone is actually cured by an alternative treatment, the false bravado of the skeptics, who invariably come streaming along shouting about the placebo effect, usually full of condescension and insults, is nothing more than that—hot air based on a belief that is founded only in myth. The simple fact is that placebos cannot cure. So those claims of successful treatment for diseases that are not subjective—such as cancer, autism, mastitis in cattle, skin conditions, or any other—cannot be denied with that off-hand line, “But, my dear, it can easily be explained by the placebo effect.” No, it cannot. And there’s the flaming straw man. -- dismissing an “alternative” therapy story in which cancer, autism, mastitis in cattle (where did that one come from?), or skin conditions were “cured” by alternative medicine as being just due to placebo effects? Cancer is a very good example. Many are the times that I’ve spoken about alternative medicine “cancer cure” testimonials, going all -- and a variety of other explanations. One thing you will not find is me trying to dismiss these cancer cure testimonials as being due to placebo effects. Indeed, if I ever saw a skeptic trying to do that, that skeptic might well himself become the target of a little bit of not-so-Respectful Insolence. And he’d deserve it, too. -- In a way, maybe Stevenson can be forgiven for thinking that the only arguments skeptics have against alternative medicine is to label it all as “placebo.” She is, as has been noted before, a homeopath, and if there is a form of “medicine” that is nothing more than pure placebo, it’s homeopathy. However, that doesn’t mean that pointing to placebo effects is the only weapon in the skeptical arsenal against the unscientific and pseudoscientific claims of alternative medicine. it is -- anxiety, or other subjective symptoms. No one—and I mean no one—tries to dismiss alternative cancer cure testimonials, for example, as mere placebo effect. Ditto the issue of autism, the “cure” of which is generally discussed in terms of development (autism is a condition of developmental delay, not stasis) and not placebo effects. Improvements in skin conditions are usually explained by how such conditions often wax and wane. In the end, I can’t help but wonder how Stevenson’s fellow quacks will react to her dismissing the ability of placebo effects to cure as a “myth.” Somehow I suspect they won’t be so happy. At least, Mike Adams won’t. Keywords: Heidi Stevenson, homeopathy, placebo, quackery (90) More » -- March 21, 2013 Busting the Placebo Myth: Placebos Don’t Cure Can we quote her next time someone proposes to harness the placebo effect? 2. #2 palindrom -- Crowd: We need a cure! We need a cure! Dr. Hibbert: Ho ho ho. Why, the only cure is bedrest. Anything I give you would be a placebo. Woman: [frantic] Where can we get these placebos? Man: (points at truck) Maybe, there’s some in this truck! (Crowd knock over truck and a box of killer bees from it break out -- March 21, 2013 Actually, Stevenson’s argument is pretty good: 1. Placebos don’t cure anything, they just make people feel better sometimes. 2. Alternative medicines cure things. ergo, Alternative medicines are not just placebos. Now, if she could only prove statement 2 were true, she’d have a case. 6. #6 Leigh Jackson March 21, 2013 So Stevenson get’s placebos but doesn’t get that CAM is a synonym for placebo. So funny one just has to cry. Compare and contrast her take with that of Jeremy Howick of the Centre for Evidence-Based Medicine (University of Oxford) in todays Times: “Placebos work… if doctors are happy prescribing them, we should take them.” Placebos don’t have to be deceptive to be clinically effective says Howick, quoting Kaptchuk’s “open” placebo study for irritable bowel syndrome. With Kaptchuk it seems like you pays your money and you makes your -- March 21, 2013 @ Helianthus: Ha. Some woo-meisters speak as if ‘placebo’ incorporated a species of healing energy that is unleashed whenever woo transpires allowing the body to heal itself perhaps through the liberation of its own energy in resonant response. In other words, sympathetic magic. In other placebo-centric news: AoA has been in an uproar about a new study that reveals (gasp!) a 2% autism rate ( a phone survey/ see LBRB). -- I lost comments due to an error on my part: Helianthus: Some woo-meisters speak as if placebo were a means to liberate the healing energy that naturallyresides within the body. Probably through resonance. In other words, magic. -- 13. #13 Denice Walter March 21, 2013 There is one thing about placebos: when you actively pursue a treatment, follow a diet, execise as well as PAY for these interactions, you are motivated to believe -- And on-topic, when, oh when!, will people stop citing Kaptchuk? Especially that study purporting to look at “not misleading people about placebos” that actually did mislead them? 17. #17 Todd W. http://www.harpocratesspeaks.com -- 18. #18 Bronze Dog March 21, 2013 The absolute most I think I’d ever say about cancer and placebos is that a placebo might make the patient feel better about the subjective symptoms. It wouldn’t do anything whatsoever about the cancer itself or any of the objectively measurable symptoms. If the cancer coincidentally went into remission, I wouldn’t give the placebo any credit for it, but alties probably would, since they so commonly rely on the post hoc fallacy. 19. #19 Krebiozen -- Stevenson’s article is one of the most jaw-droppingly dumb I have read in a long time. Homeopaths and acupuncturists make a living by persuading patients to mistake a placebo effect for a real effect of their treatment. A paper on placebo use came out today:Placebo Use in the United Kingdom: Results from a National Survey of Primary Care Practitioners Placebo use is common in primary care but questions remain about their benefits, harms, costs, and whether they can be delivered ethically. Further research is required to investigate ethically acceptable and cost-effective placebo interventions. 20. #20 Krebiozen March 21, 2013 -- “This latest study with the University of Oxford demonstrates that doctors are generally using placebos in good faith to help patients,” says Professor George Lewith, co-lead author of the study from the University of Southampton. “Other previous published studies by Southampton have clearly shown placebos can help many people and can be effective for a long time after administration. The placebo effect works by releasing our body’s own natural painkillers into our nervous system. In my opinion the stigma attached to placebo use is irrational, and further investigation is needed to develop ethical, cost-effective placebos.” That’s not quite how I see placebos. Has it really been demonstrated that placebos work, “by releasing our body’s own natural painkillers into our nervous system”? I thought much of what is called “the placebo effect” isn’t really an effect at all, but an illusion collectively caused by regression toward the mean and various cognitive biases. If we are talking about subjective changes due to suggestion, perhaps we should call them that, and abandon the term “placebo effect” altogether as hopelessly misleading. 21. #21 Mike Olson -- American.” Just trying to give you an idea of my background. I read a book called something like, “Hacks, Quacks and Big Pharma flacks.” Which seemed to truly contradict the notion that placebos did nothing to help a person feeling better. Simply believing a med or procedure would work better or make a person feel better -- I don’t bring this up to contradict any argument against snake oil salesmen( or women), but rather to suggest that a premise of, “Placebos just make a person feel better it they don’t make them better,” is probably wrong. At least from what this ill informed, somewhat literate lay person has read. -- I read a book called something like, “Hacks, Quacks and Big Pharma flacks.” Which seemed to truly contradict the notion that placebos did nothing to help a person feeling better. Simply believing a med or procedure would work better or make a person feel better actually -- anything meaningful? No, in order to say that you’d have to measure an actual clinical outcome. In short, saying “placebo works, look, I can measure a change in this lab value” can be accurately translated as “look, placebo doesn’t really do anything, since the most effect I can find is in some random lab value rather than talking about a clinical result.” -- March 21, 2013 https://www.youtube.com/watch?feature=player_embedded&v=ntWO7jnOcWE How placebo prescribing may work in practice. 26. #26 Leigh Jackson March 21, 2013 @ Krebiozen, 18,19 The oh-so-cautious official conclusion of the study regarding the scientific and ethical status of placebos belies the two co-leads loud and laudatory public endorsement of GPs use of placebos. The only unequivocal thing the study recommends is further research on placebos. Hardly surprising given that Lewith heads one of the two co-funders of the study. “The Southampton Complementary Medical Research Trust was -- 27. #27 Denice Walter March 21, 2013 I would so totally NOT go with concept of the placebo effect being an expression of endogenous opiates. 28. #28 S March 21, 2013 Doctors that prescribe placebos to their patients should be paid with placebo cash. Turnabout is fair play, right? 29. #29 Krebiozen March 21, 2013 -- responses…according to the book. I think this is a common misconception. Most clinical trials compare an active treatment to a placebo, and it is easy to assume that any measured changes in patients in the placebo arm of the study are caused by the placebo. If you look at clinical trials that include a ‘no treatment’ arm, you will usually find that patients who have no treatment do just as well as those given a placebo. My favorite example is this study which is often cited as evidence that sham knee surgery (making an incision and then simply sewing it back up) is as effective as lavage (washing out the joint) and debridement (basically scraping out the joint), thus demonstrating the awesome power of the placebo. However: The authors found that all three treatment groups fared equally: -- we don’t even know if patients given no treatment at all might have reported a similar reduction in pain over time, since the study lacked a no treatment group. The placebo wasn’t awesome at all, it was as useless as the surgical interventions. Similarly, you can find lots of studies of alternative therapies that are essentially placebos, for example therapeutic touch, that have no consistently measurable effect on an objective measure, for example, wound healing, as in this study. If you can find a study that shows a placebo has a consistent and significant objectively measurable effect as compared to no treatment I would be very interested. -- March 21, 2013 Leigh Jackson, Thanks for the information on the authors of that placebo study, which confirms my suspicions. 31. #31 Denice Walter -- book, however, that if persons had some sort of infection and were given antibiotic, their immune system would respond with a given set of antibodies. Over time, even if they were given a placebo that appeared similar to the antibiotic, their bodies would still respond with the same antibodies. It seemed like an odd effect…perhaps I read it wrong. The author did indicate that essentially all persons are susceptible to the placebo effect and it had nothing to do with being “weak minded” or some defect of character. Again your response seems to be in the same vein as what he had written. -- Mike Olson, Over time, even if they were given a placebo that appeared similar to the antibiotic, their bodies would still respond with the same antibodies. -- study found you can condition a rat’s immune systems to respond to an audiovisual cue, for example. It’s interesting, but I don’t see how that means placebos ‘work’ in the sense of having an objective effect on the body. It sounds to me as if the author of that book is looking for explanations of how placebos ‘work’, when the best evidence suggests that they don’t. 40. #40 Krebiozen March 22, 2013 Maybe I should declare myself as a lapsed placebo-effect believer – a few years ago I was hopeful that the field of psychoneuroimmunology would revolutionize medicine, but I have been -- That’s pure suggestion, but I would be willing to bet that there was no objective improvement in his leg. I think that’s the extent to which placebos ‘work’. As to whether this is clinically useful, I think that’s debatable. In the sense that a placebo may persuade a patient to go away and stop bothering a doctor, then perhaps they have a use. On the other hand prescribing antibiotics for viral infections as a sort of placebo has contributed to the spread of resistant bacteria, and feeling better when you’re not can be dangerous, in asthma for example. -- Gurgaon, India March 22, 2013 Placebo is an inactive dummy/inert pill (substance such as lactose/saline which do not alter the disease condition) prescribed to the patient for enhancing he non-specific effects of the -- see a doctor working to help them, they might report improvement, even if there is none, to avoid impugning the doctor’s competence. That’s probably one of the more subtle components of the placebo effect: Some patients will lie, understate, or exaggerate to make the doctor feel better. -- Nancy Malik who has been described as a “homeopathy shill, fact-blind delusional crank and serial comment spammer” . I suppose that’s appropriate for a post about placebos. 45. #45 Beamup March 22, 2013 @ Nancy: That is not accurate. The concept of a placebo is very much broader. A nice chat with a “practitioner” who assures you they can fix anything that’s wrong, for example, would very much qualify by -- “evidence-based homeopathy” to understand that. The only legitimate evidence-based view of homeopathy is that it is completely bogus and does nothing… because it is, in fact, a placebo. 46. #46 Krebiozen March 22, 2013 -- 48. #48 Tom Herling March 22, 2013 Audio engineers will often rely on placebo effect to placate some impossible client who, during a recording session wants more “purple”–our code for some inaudible but highly desired effect. -- 49. #49 Leigh Jackson March 22, 2013 Re: placebo, qua endogenous opiates cum psychoneuroimmunology cum clasical conditioning. Would be interested to hear views on the work of Fabrizzio -- in a day or two when I have had time to ponder it properly, as it’s an area that still greatly interests me. Briefly, placebos do appear to have an effect on perceived pain, but I wonder if that is as significant as the authors you refer to think. If I stomp on someone’s foot it may increase their endorphin levels and/or distract from a pain elsewhere in their body, and this effect would also probably be blocked by an opiate antagonist like naloxone. I suspect the effect of placebos on subjectively assessed conditions such as pain may be similar to this. The important question is whether this is clinically useful, and I’m -- Krebiozen, Thanks. We think alike. Howick and Lewith speak as if it’s all a done deal: placebos do produce clinical benefits and the mechanism is understood. They are calling on the GMC to allow free prescription of placebos on the basis that it already happens and that research like Benedetti’s validates the practice. I trust that the GMC has a fuller picture than I do on the overall -- 53. #53 Melissa G March 23, 2013 So, speaking of placebo effects, and it’s evil Mirror Universe twin, nocebo here’s a Slate article about wind farms and people who live near them freaking out. -- I have been reading the studies Leigh referred to, and some others, but I’m feeling more confused, if anything. For example they found that only 30-40% of patients respond to placebos, and that some types of placebo-induced analgesia are blocked by naloxone (which is an opioid inverse agonist, not an antagonist as I stated above) while others are not. It seems weird to me that the human body can -- to 70% of patients doesn’t seem very useful to me. By way of taking a step back from this, I looked at the Wikipedia article on placebos for the first time in several years, and found it very useful. It discusses, for example, Hróbjartsson and Gøtzsche’s Cochrane review (PMID: 20091554) of placebos that concludes: We did not find that placebo interventions have important clinical effects in general. However, in certain settings placebo interventions can influence patient-reported outcomes, especially pain and nausea, though it is difficult to distinguish patient-reported effects of placebo from biased reporting. The effect on pain varied, even among trials with low risk of bias, from negligible to clinically important. Variations in the effect of placebo were partly explained by variations in how trials were conducted and how patients were informed. Oddly, Wikipedia mentions criticisms of this review on the grounds -- Their meta-analysis covered studies into a highly mixed group of conditions. It has been reported that for measurements in peripheral organs the placebo effect seems to be more effective in achieving improvements in physical parameters (such as decreasing hypertension, improving FEV1 in asthma sufferers, or decreasing -- parameters (such as cholesterol or cortisol) in various conditions such as venous leg ulcers, Crohn’s disease, urinary tract infection, and chronic heart failure. Placebos also do not work as strongly in clinical trials because the subjects do not know whether they might be getting a real treatment or a sham one. Where studies are made of placebos in which people think they are receiving actual treatment (rather than merely its possibility) the placebo effect has been observed. Other writers have argued that the placebo effect can be reliably demonstrated under appropriate conditions. Can placebos really achieve improvements such as “decreasing hypertension, improving FEV1 in asthma sufferers, or decreasing prostatic hyperplasia or anal fissure”? That question led me to this meta-analysis, which did a MEDLINE search for placebo-controlled studies on “peripheral disease processes”. However, I note that they state: Because the selected trials did not include untreated control groups, we restricted the dataset to trials on stable disease conditions, from which the effects of placebo treatments could be estimated by baseline changes within the placebo groups. No untreated control groups again, which leaves me feeling somewhat underwhelmed by the barely significant placebo effects on physical parameters they found in this and on reanalyzing Hróbjartsson and Gøtzsche’s data. I’m reminded of studies on homeopathy and -- March 24, 2013 We feel happy if good stuff happens to us: “here is something to help you feel better” – a placebo. The good stuff here is someone saying they can help us to feel better: lo and behold we do feel a little better! The placebo works? Nope. The good news worked – subjectively. Turn it all round: if we feel good then good stuff will happen to us. This is what needs to be true if a placebo is to cause objective clinical benefits. The good news that someone has something to help us makes us happy and then our feeling of -- Obviously too good to be true except at the margins of bodily health. And then not at all easy to demonstrate. As for the idea of non-deceptive placebos, pull the other one. If you can see you are only getting a toothpick prick of your skin and not an acupuncture needle into your flesh you are not going to get the magical placebo benefit of acupuncture; now are you? For the magic trick to work you need deception. 56. #56 Dr. Nancy Malik -- getting better because of the therapeutic effects of the medical treatment/intervention. 2. Non-specific (psychological/placebo) effects:The body’s healing response is activated 57. #57 Chris -- Nancy Malik, Non-specific (psychological/placebo) effects:The body’s healing response is activated Maybe I’m lucky, my body activates its healing response automatically, without any need for particular psychological conditions or a placebo, and rarely requires assistance from active outside agents. Why would the body require a placebo to persuade it to activate its healing response? 59. #59 Denice Walter -- @ Krebiozen: No no no! The placebo activates the inherent bioenergetic sytem (TM) which has been a-slumbering, its Xi ( qi, ki, mana, prana, life energy et al) obviously requires raw food, hand waving, energy medicine, -- Denice, The placebo activates the inherent bioenergetic sytem [...] It seems like a serious design fault to me, having these marvelous inherent painkilling and healing abilities that only do their thing -- experience suggests that plenty of chicken scraps work just as well, which makes me wonder if it isn’t sarcoptic mange at all, but some sort of vitamin deficiency. Or perhaps placebos work on foxes, which neatly brings us back to the topic in hand. 63. #63 Khani -- 75. #75 Grant March 25, 2013 (Should say doesn’t work beyond a placebo effect, but you all know that right?) 76. #76 JGC -- in your opinion is the single most compelling piece of evidence demonstrating that homeopathy is more effective at treating non-self-limiting illnesses than are placebo’s (i.e., that it actually works)? 77. #77 Dr. Nancy Malik -- March 25, 2013 I’ve really enjoyed reading the debate between Krebiozen and Leigh Jackson. But do feel that there is a lot more to placebos than a subjective response of feeling better. Placebos cannot cure cancer, diabetes, cardiovascular disease etc. But they can improve pain perceptions. Specifically in sport and exercise. -- supplement compared to a positive expectancy. http://europepmc.org/abstract/MED/17876973 There are many more in the sport and exercise field where a placebo can improve an athletes performance. If the person can run faster does that not mean the placebo has worked? 84. #84 MI Dawn March 25, 2013 -- Mark James, If the person can run faster does that not mean the placebo has worked? It depends on what you mean by “worked”. I’m certainly not denying that placebos can have subjective psychological effects. Nor would I deny that those subjective psychological effects can affect a person’s neurochemistry, physiology or behavior, including sports -- patient is given an active treatment as Orac suggested in the OP. Hypnotherapy is essentially a way of harnessing this element of the ragbag of things that are collectively referred to as “the placebo effect”, but without the need to deceive the patient. So are therapies like counseling, massage, yoga or taking a walk in the -- interesting to know, though what the study really shows is that the ‘performance enhancing’ supplements they were testing had no effect above placebo. It would be interesting to compare the effects of a placebo with the effects of superstitious amulets like a pair of lucky socks, visualization, a pep talk etc. etc.. I strongly suspect the exact same phenomenon is involved. 88. #88 (Long) Weekend Reading | Science-Based Pharmacy March 29, 2013 [...] The “myth” of placebo effects [...] 89. #89 Antilusional April 12, 2013