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EVIDENCE THAT PLACEBOS COULD WORK
EVEN IF YOU TELL PEOPLE THEY¹RE TAKING PLACEBOS
We have drawn your attention to this article because we are very interested in the capacity of your mind to influence your health, both positively and negatively. We know from sports medicine that a positive attitude and perseverance is so important to desired outcomes. We try to encourage positive beliefs from our clients knowing how helpful these are based especially on the work of Bruce Lipton. N.B his Best Science Book of the year publication Biology of Belief. - John Coombs
Discover Magazine
December 22, 2010
In many medical studies, even people who take ³fake² treatments, such as
sugar pills with no active ingredients, can still feel better. These are the
puzzling ³placebo effects. They are common, diverse and powerful and they
raise an interesting ethical question -- can doctors justifiably prescribe
placebos to their patients? The standard answer is no. Doing so patronises
the patient, undermines their trust, and violates the principles of informed
consent. It compromises the relationship between doctor and patient. At
worst, it could do harm.
But many of these arguments are based on the idea that placebo effects
depend on belief; people must expect that treatments will work in order to
experience any benefits. For a doctor to prescribe a placebo, they¹d need to
deceive. But according to Ted Kaptchuk from Harvard Medical School,
deception may not be necessary. In a clinical trial, he found that patients
with irritable bowel syndrome (IBS) felt that their symptoms improved when
they took placebo pills, even if they were told that the pills were
inactive.
Fabrizio Benedetti, a placebo researcher at Turin Medical School who wasn¹t
involved in the study, says, ³Although several studies suggested that
placebos can be equally effective without deception, this is the first
rigorous study that provides scientific evidence for this.²
Referring to an earlier study published in the British Medical Journal
<http://www.bmj.com/cgi/content/full/337/oct23_2/a1938>, he says, ³We did
the study because we knew that physicians were giving placebo to patients
secretly without informed consent. Our study was designed to test whether
placebo effects could be harnessed without this secret deception.²
The trial
He recruited 80 patients with IBS and randomly split them into two groups:
one who took a placebo pill twice a day, and another who didn¹t take any
treatments. Throughout the study, Kaptchuk¹s group were honest and open
about the nature of the trial. Every patient had a detailed consultation
with one of the team, who explained that placebo pills were ³inert or
inactive pills, like sugar pills, without any medication in it².
They told the patients that ³placebo pills, something like sugar pills, have
been shown in rigorous clinical testing to produce significant mind-body
self-healing processes.² And they explained: that ³the placebo effect is
powerful; the body can automatically respond to taking placebo pills like
Pavlov¹s dogs who salivated when they heard a bell; a positive attitude
helps but is not necessary; and taking the pills faithfully is critical.²
Before the trial, the patients answered several questionnaires about the
severity of their symptoms, whether they had recently improved or worsened,
whether they experienced any relief from their symptoms, and their quality
of life. After 21 days, they answered the same questions again. Kaptchuk
found that those who had been taking placebo pills felt better than those
who didn¹t take anything. They reported more relief and larger improvements
in their symptoms, which had become less severe. Only quality of life was
not significantly different between the two groups.
This isn¹t entirely new. In 1965, Lee Park and Lino Covi asked 15 neurotic
patients at a psychiatric clinic if they wanted to try a sugar pill that
could help them, even though it had no actual medicine. The patients agreed
and the pills helped to reduce their symptoms. Kaptchuk¹s trials extends
upon that historical study by adding a control group.
Great expectations
³We did this study on a shoe-string,² says Kaptchuk. ³No one would fund a
study that was going to tell patients that they were going to get placebo.²
In the end, funding came from the National Center for Complementary and
Alternative Medicine. While they have a somewhat murky track record in terms
of the science they fund, no one I spoke to criticised the design of this
trial.
Edzard Ernst, a professor of complementary medicine at the University of
Exeter, says, ³This is an elegant study which suggests that the ritual of
giving a patient a remedy is clinically effective, even if that patient has
been told that the remedy is a placebo.² Kaptchuk himself says, ³I suspect
that just performing ³the ritual of medicine² could have activated or primed
self-healing mechanisms.² And Amir Raz, a neuroscientist who studies
placebos at McGill University, adds, ³Scientific reports make it clear, even
if strange and counterintuitive, that receiving -- rather than the actual
content of -- medical treatment can trigger and propel a healing process.²
But did the patients actually expect the placebos to Œwork¹? Here¹s where
the paper gets frustrating. After the trial, Kaptchuk used a survey to check
that the patients understood the experiment. A few titbits are published:
for example, the placebo group mostly thought that their pills contained
Œsugar¹, with some suggesting Œnothing¹, Œflour¹ or Œcalcium¹. That seems
strange -- it would be fascinating to know if the patients experienced
greater benefits depending on their expectations.
But the surveys also asked what the placebo group thought about the idea of
taking placebo, and whether they were sceptical or expected it to work.
These results ³will be reported elsewhere.² Kaptchuk said, ³We haven¹t
written them up yet. Combining a quantitative study with a qualitative study
is difficult and editors don¹t give you enough roomŠ Medical journals aren¹t
good with qualitative data.²
Regardless, Kaptchuk thinks that people don¹t need to believe that the
placebos will work. ³My hypothesis is that much of what we did was just
below conscious expectation,² he says. ³We even told patients they didn¹t
have to believe it would work (although we also gave them good reasons for
expecting that it would)²
Limits and implications
Kaptchuk acknowledges a few other weaknesses. It only looked at a small
number of patients and it was quite short. Indeed, it was only meant as a
³proof-of-principle² study, which will now need to be checked with larger,
longer trials.
More importantly, the study wasn¹t a fully ³double-blind² trial, where
neither patient nor scientist knows who has been assigned to which
treatment. Kaptchuk¹s team certainly had no idea which group the patients
were in. But there was no way of ensuring that the patients were similarly
ignorant, when some were clearly taking pills and others weren¹t. The
apparent benefits of the placebo pills depended on the patients reliably and
comparably reporting what they felt, for a condition that naturally waxes
and wanes. Those who took placebos might have felt pressure to feel better,
and this problem can¹t really be overcome in a trial that compares placebos
to no treatment at all.
This might not matter, given that the study measured subjective experiences
anyway. If a patient says that they feel better, that¹s arguably a good
result. Kraptchuk realises this and only suggests that placebos could be
used transparently for ³illnesses primarily diagnosed by subjective symptoms
and introspective self-appraisal². Placebo pills aren¹t going to be
shrinking tumours any time soon, but they may prove useful for conditions
like depression, anxiety or chronic pain.
Ernst isn¹t convinced. He says, ³The effect size is probably too small to be
clinically relevant. [It] is unlikely to be of practical use.² To him, the
results are interesting ³mostly from a theoretical point of view². But
Kaptchuk thinks that the effect he saw is ³clinically meaningful², and
comparable to some drugs being tested for IBS such as alosetron.
All in all, Kaptchuk thinks that the prescription of placebos doesn¹t have
to violate the ethics of modern medicine. If delivered with ³a plausible
rationaleŠ without deception or concealment², they can produce improvements
in a patient¹s symptoms (indeed, Janet Stemwedel, ethicist and science
blogger, proposed a similar situation in which it might be ethical to
prescribe a placebo) At the very least, he says that ³open-label placebo may
have potential as a ³wait and watch² strategy before prescriptions drugs are
prescribed.
Does the new trial add another dimension to the debates? Not yet. Raz says,
³These results are not new per se but they are interesting and replication
is of utmost importance in science, especially when controversy rules. The
use of placebos is ethically tenuous and will probably remain so for a while
longer, but this effort is a step in the right direction. It shows that we
can use placebos non-deceptively -- a genuine placebo medication.²
Benedetti adds, ³There is not a single placebo effect but many, with
different mechanisms (expectancy, conditioning, reward, anxiety modulation,
genetic variants, and the like) and in different systems and conditions. The
challenge for the future is to understand all these complex interactions and
exploit them ethically at the bedside.²
.............
Pulse on Placebos:
http://nhne-pulse.org/resource_pages/the-placebo-effect/
http://nhne-pulse.org/placebos-may-work-even-when-people-are-told/
http://blogs.discovermagazine.com/notrocketscience/2010/12/22/evidence-that-
placebos-could-work-even-if-you-tell-people-they%E2%80%99re-taking-placebos/ |
