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WISHFUL MEDICINE: PLACEBOS, NOT PILLS
Book Reviews By Stephan Herrera, Technology
Review, July 2005
The Anatomy of Hope:
How People Prevail in the Face of Illness
By Jerome Groopman
Random House, 2004, $14.95
The Role of Complementary and Alternative Medicine:
Accommodating Pluralism
Edited by Daniel Callahan
Georgetown University Press, 2002, $29.95
The western medical establishment and drug industry have an uneasy relationship
with the placebo effect. Both acknowledge that patients often benefit
from their own expectations. But neither seems willing to support efforts
to study the underlying physiology of the effect.
After reading Jerome Groopman's The Anatomy of Hope and Daniel Callahan's
The Role of Complementary and Alternative Medicine, and much of the body
of peer-reviewed research on the biological basis of the placebo mechanism,
one begins to understand why placebo-enhanced healing gives doctors pause.
There is growing evidence of its existence but little conclusive data
as to how and why it works. And there is even less research on how to
best manipulate the effect for the welfare of patients.
Groopman is a Harvard Medical School physician and a New Yorker writer
whose articles offer a rare glimpse of the difference between the way
medicine is taught and the manner in which it is practiced. For almost
20 years, Groopman suffered chronic and debilitating back pain. As we
come to learn in Groopman's memoir, the placebo effect, set into motion
by the encouragement of a straight-talking yet exceedingly empathetic
doctor at a small physical-therapy clinic near Boston, played a pivotal
role in his recovery. Anatomy of Hope describes Groopman's road to recovery
and the lessons he learned from it that now inform his work as both a
teacher and a clinician. The book is a testament to the power of the human
spirit--and to the health and economic value of the placebo effect--from
a highly credentialed member of the medical establishment.
Callahan approaches the issue of healing from a different vantage. He
is not a physician but a philosopher. Callahan is cofounder of the Hastings
Center in Garrison, NY, which is devoted to the study of bioethics. He
is very much outside of the medical establishment but has featured prominently
in every major biomedical debate in the United States in the last 35 years.
This book is a collection of essays and reviews on the subject of alternative
medicine and the placebo effect. Callahan says in his introduction that
he compiled the book in an attempt to understand why a "large and
prestigious group of clinicians and biomedical researchers seems so utterly
hostile to [alternative medicine] while a large portion of the public
(and the educated public at that) seems so attracted to it."
These two authors each have their own reasons for being intrigued by
the power of the placebo effect. But a common theme can be found in both
books--namely that the placebo effect is not a figment of a patient's
imagination. And there are now technology and studies to prove it.
Feeling Is Believing
Latin for "I shall please," the placebo takes many forms, the
most common of which are the sugar pill, the saline injection, and distilled
water. There are even placebo surgeries wherein patients are anesthetized,
cut open, and stitched up to look as if they have had surgical interventions,
even though they haven't. The belief and expectation that a treatment
will heal produces in many patients genuine feelings of relief. In some
patients, there is even physical evidence of a benefit.
Doctors and researchers first discovered in 1931 that the placebo effect
was a useful prop for better understanding the safety and efficacy of
medicines in development. It was well known that some patients would say
that they felt better at the very suggestion that they were being given
a remedy. Researchers trying to measure the effects of a drug called sanocrysin
on patients with tuberculosis wanted to control for this anomaly. Their
solution was to give patients a glass of distilled water and tell them
they were drinking sanocrysin. Ever since, placebo-controlled, double-blind
studies have been embraced by the medical profession as a standard way
of evaluating drugs in clinical trials.
But what has long puzzled researchers is whether the sense of healing
that some patients feel when given a sugar pill is a function of human
biology or psychology. It turns out that it's both. New research indicates
that in cases of maladies like chronic pain, asthma, and depression, a
person's expectation of healing sets off a chain reaction of neurochemical
changes in the body that can alleviate physical symptoms.
As Groopman writes of Ted Kaptchuk's placebo work at Harvard Medical
School, "a change in mind-set can alter neurochemistry, both in a
laboratory setting and in the clinic. When we are patients, suffering
from pain and debility, we look to our doctors and nurses for the words
and gestures that reinforce our belief in medicine's power and solidify
our expectation that we may benefit from an intervention. Recent research
shows just how catalytic those neurochemical changes can be."
Groopman writes that "belief and expectation--the key elements of
hope--can block pain by releasing the brain's endorphins and enkephalins,
mimicking the effects of morphine" and can affect "fundamental
physiological processes like respiration, circulation, and motor function."
As Groopman notes, hope can trigger a placebo effect whose biology "can
be imagined as a domino effect, a chain reaction in which each link makes
improvement more likely."
Research supporting the biological basis of the placebo effect has been
appearing with greater frequency in peer-reviewed journals like Science,
Nature, and the New England Journal of Medicine and in nearly all of the
leading specialty journals in the depression and pain treatment field.
One of the definitive analyses of the placebo effect's role in treating
depression remains a 1998 meta-analysis--a study that reviews previous
studies in search of themes and conclusions--by Irving Kirsch and Guy
Sapirstein called "Listening to Prozac but Hearing Placebo: A Meta-Analysis
of Antidepressant Medication," which appeared in Prevention and Treatment.
Deciphering the data on the subject, Kirsch and Sapirstein discovered,
suggests that the placebo effect might account for up to a third of the
clinical benefit of modern antidepressants.
The analysis raises an obvious question: might more clinical benefit
be achieved if the placebo effect could be harnessed and directed? And
given the physical, emotional, and economic cost of depression, why isn't
the government funding more research on the placebo effect's potential
role in treating it?
Pain is the object of most placebo-effect studies, many of which use
brain imaging to compare and correlate the biological activity produced
by opiates like morphine with treatments that stimulate the placebo effect.
One such study appeared in the Feb. 20, 2004, issue of Science, describing
work done by the University of Michigan's Tor Wager (now at Columbia University)
and colleagues from Princeton University, Harvard University, the University
of Wisconsin, and the Veterans Affairs Medical Center at the University
of Michigan. The team of researchers discovered in two functional magnetic-resonance
imaging experiments that placebo analgesia is related to decreased brain
activity in pain-sensitive brain regions, including the thalamus, insula,
and anterior cingulate cortex.
The researchers also observed increased brain activity in the prefrontal
cortex when pain--or pain relief--was anticipated, which would seem to
offer some evidence that placebos alter the experience of pain. In July
2002, the New England Journal of Medicine published a study that found
that patients who underwent a placebo surgical procedure instead of a
type of arthroscopic surgery did just as well as patients who actually
received the surgery.
The importance of these and other recent findings is twofold. First,
they show that more researchers and scientific publications are taking
seriously the placebo effect. Second, it is clear that researchers are
now seeking to go well beyond correlation studies, instrumental as they
are for defining the broad reach of the placebo effect. The new goal of
placebo-effect researchers is to establish and identify a direct cause-and-effect
link between the placebo effect and physical healing in a wide variety
of diseases.
Suspended Disbelief
Many experts point out that recent brain-imaging studies purporting to
prove the existence of a placebo response are suggestive but far from
conclusive. Howard Brody, whose chapter on the placebo effect appears
in Callahan's book, warns against reading too much into brightly colored
brain scans that seem to show how certain regions of the brain "light
up" when the placebo effect is induced. Brody, who is a family physician
and researcher at Michigan State University, says, "I support the
idea that PET [positron emission tomography] scanning data are helpful
because they suggest which brain centers are involved in placebo effects
and thereby suggest possible neural mechanisms that can be explored in
future studies." But, Brody adds, "I don't agree with the notion
that the placebo effect can now be proven to be real [just] because we
can see it on a PET scan."
To pinpoint the mechanisms responsible for the physiological changes
associated with placebos, defenders of the effect will have to work more
closely with their skeptical peers. Proponents have made much scientific
progress and picked up some key endorsements. But they need to work harder
to identify the type of research that will fully explain the phenomenon.
In turn, the medical community needs to be more open to the potential
benefits offered by placebos.
The most obvious common ground between the two camps is the economic
imperatives they both face. If enthusiasts of the placebo effect want
more notice and respect, they must prove the financial advantages of promoting
the effect as a way to boost and supplement mainstream treatments. They
must show that higher expectations will mean faster healing and better
quality of care and will save money. That's a message that will surely
carry weight in the economically stressed health-care industry. As Groopman's
book illustrates, the practice of medicine ultimately comes down to what
happens at the bedsides of patients. And there, Groopman reminds us, it's
worth keeping in mind the value of hope as a powerful and very real medicine.
Stephan Herrera is a contributing writer for Technology Review who often
writes about the business and politics of health care.
http://www.technologyreview.com/articles/05/07/issue/review_medicine.asp?
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Copyright 2005 Technology Review Inc.
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