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More credulous reporting on placebo effects [Respectful Insolence]
Now that Trine Tsouderos no longer works for the Chicago Tribune, there aren’t that many reliable generalist medical/science reporters around any more. There’s Marilyn Marchionne at the AP, Gina Kolata o the New York Times, and then there’s Sharon Begley, who used to be at Newsweek but is now at Reuters I’m having trouble thinking of others with national prominence, other than Nancy Snyderman, who has recently profoundly disappointed me with a fawning report on “complementary and alternative medicine” (CAM) that made it seem to be the greatest thing since sliced bread, and Sanjay Gupta. Unfortunately, although Marchionne is rock-solid reliable when it comes not to falling for the blandishments of quackademic medicine, Sharon Begley is less reliable. For every article in which she’s right on target (for instance, this one, where she explains why a study that purported to show that cancer survival is worse in Europe shows nothing of the sort or this one about Steve Jobs’ cancer), she churns out articles that come to very dubious conclusions. In particular, a few years ago she really annoyed me with a truly clueless rant about doctors “hating science.” Unfortunately, her most recent article in The Saturday Evening Post, Placebo Power, is more like the latter than the former.
Very frustrating.
It’s been a while since I’ve written about placebo effects, at least as the main topic of a post. I must admit, my views on placebo effects have evolved over the last couple of years to the point where I now think much less of them than I used to. Not all that long ago, I used to buy somewhat into the current narrative that placebo effects are powerful. Since then, however, over time I’ve come to the conclusion that most doctors don’t really understand placebos. Unfortunately, CAM practitioners, who apparently have switched from “complementing” real medicine with quackery to “integrating” quackery into real medicine to produce “integrative medicine,” have seized upon placebo effects to justify their nostrums, having apparently started to realize that science and evidence are not showing any specific therapeutic effects attributable to their woo. “Hey!” they seem to be saying, “I know that acupuncture doesn’t really do anything, but it invokes the powerful placebo effect, and that’s what heals. Heck, you can even have placebo effects without deception.” (No, you can’t.)
Don’t believe me? Then get the hence to some of my old posts, where I argue that this use and abuse of placebo medicine by CAMsters is in reality a manifestation of a very old aspect of medicine: Paternalism. It’s also more than a bit of magical thinking. Unfortunately, a lot of journalists eat this stuff up, basically doing the quackademics’ work for them and serving as mouthpieces for their messages. Sadly, that’s the function Begley’s most recent piece serves, and it doesn’t take long for her to fall for the “wishing makes it so” fantasizing that so often characterizes reporting on placebo medicine. After an example of patients feeling better after placebo interventions, Begley leaps to this speculation that could have come from Ted Kaptchuk himself:
It is tempting to say that “mere thought” or “mere belief” caused these patients to feel and function better, just as the child’s trust in her mother made her knee feel better and our belief that little white pills will relieve a headache made the calcium tablet do so, even though it contained not a speck of headache-fighting medication. But if doctors and scientists have learned one thing about the placebo response or placebo effect, it is this: There is nothing “mere” about how thoughts, beliefs, and the power of the mind affect the body.
As researchers find more and more conditions that respond to placebos, they are gaining new respect for the power of mind. They are also learning how a belief or expectation can travel from the brain to arthritic knees, asthmatic airways, hypertensive blood vessels, and sites of pain. Understanding these mechanisms holds out the promise of tapping the placebo response more systematically, so more illnesses can be treated not with pills and operations (which almost always come with side effects or other risks) but with the power of the mind. “What we believe and expect can significantly influence the outcome of a disease, how much pain we feel, even whether Parkinson’s symptoms diminish,” says neuroscientist Mario Beauregard of the University of Montreal, who examines the brain basis for the placebo response in his 2012 book, Brain Wars.
No, what we believe and expect can influence the subjective symptoms of a disease or condition. There’s no good evidence that what we believe and expect can have a significant effect on hard outcomes. For instance, there’s no evidence that placebo effects or expectation can result in prolonged survival or a better chance of a remission in cancer treatment. The only time one can reliably see placebo effects is for the measurement of more subjective outcomes, such as pain, nausea, and the like, but the effects are highly variable. Moreover, although Begley seems oblivious to components of observed placebo effects that are not magical or due to the “power of the mind,” such as observer bias and other undetected biases in clinical trials. Indeed, it has been said that much of what is reported as “placebo effects” is actually an artifact of how randomized clinical trials are carried out. Not necessarily all, but, let’s just put it this way: Although I’m not sure I’m ready to come to the conclusion that Mark Crislip has come to argue that there is no placebo effect, although I do agree with him that the placebo response represents “the beer goggles of medicine” in that much of what is being observed are changes in the patient’s perception of his or her symptoms rather than true changes in the underlying pathophysiology.
An excellent example of this was a study that we discussed at TAM a couple of years back in which placebos were tested in asthma, along with real asthma medicine. The studie’s been blogged about extensively; so I’ll cut to the chase, rather than explaining it in my usual Orac-ian detail. Basically, patients receiving the placebo acupuncture felt better, as good as those who received treatment with a real albuterol inhaler. However, the pulmonary function tests did not bear that out. Basically, the placebo intervention produced the illusion of improvement, which in the case of a disease like asthma, where it is function, not symptoms, that determine how sick a patient is. It is not hard to imagine a situation in which a placebo intervention falsely leads a patient to feel better, even though his pulmonary function hasn’t improved. Given the nature of asthma, such a false sense of confidence could easily lead to a patient’s death, because it’s not too uncommon for asthma patients to be reasonably functional up to a certain point of lung function deterioration and then be “tipped over the edge.” In other words, it’s not good to give asthma patients a sense of feeling better if their lungs are not actually functioning better.
Funny that Begley didn’t mention that study, although she did mention asthma as a disease that placeboes could effect. She does, however, mention a whole bunch of studies that, as you might expect, use subjective outcomes. Well, most of them discuss subjective outcomes. One of them is about Parkinson’s disease:
In Parkinson’s disease, production of dopamine in structures called the substantiae nigrae declines. That means dopamine, the very same molecule whose production is raised when we expect something good to happen to us, is AWOL in Parkinson’s. Scientists led by neurologist Jon Stoessl of the University of British Columbia gave a small group of Parkinson’s patients injections of a saline solution but told them it was medication. Sure enough, the patients’ brains began producing more dopamine and their movements became better controlled and less shaky—improvements equal to those in patients who received an actual Parkinson’s drug. In Parkinson’s disease, “the placebo effect is real, it’s huge and it’s got a physiological basis,” Stoessl told the journal Nature.
It’s true that Stoessl said this in a news article in 2011. What Begley fails to note is that in the very same Nature article, his assertion is questioned:
Many regard bias as a more significant confounder. “Investigators have a tremendous vested interest in seeing that their treatment is effective,” says Anthony Lang, a neurologist at the University of Toronto in Canada who has participated in several neurosurgical trials for experimental Parkinson’s therapies. In any trial, bias can affect how researchers assess patient responses and may inflate the patients’ expectations, further enhancing the placebo effect. Compounding the problem for Parkinsons’ research is the fact that there are no objective measures for how well a patient is doing. “It’s just a sort of perfect storm conspiring against our ability to see definitive changes in the underlying disease,” says Steven Piantadosi, a clinical-trials methodologist at Cedars-Sinai Medical Center in Los Angeles, California. “Sham surgery, properly done, can control for that.”
Throughout the entire article, there is very little in the way of anything that resembles significant skepticism regarding the statements made by the people she interviews, all of whom are clearly believers in placebo effects, in particular Ted Kaptchuk, whom we’ve met on multiple occasions before on this very blog. She even completely buys into Kaptchuk’s infamous study from a couple of years ago in which he claimed he had demonstrated that he could induce placebo effects without deception, describing it straight, as though, yes, that’s exactly what Kaptchuk had shown. As it turns out, he had shown nothing of the sort, having in fact used a bit of deception about the placebo, despite his spin.
In the end, Begley fell for nearly every trope that CAMsters who have co-opted placebo effects as the explanation how their woo allegedly “works” want people to believe. I’m hoping that she redeems herself with her next story, but I’m not counting on it.
2013-01-16 01:45:23
Source: http://scienceblogs.com/insolence/2013/01/16/more-credulous-reporting-on-placebo-effects/
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