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Why Do Placebos Work? A new series of studies will examine why people who take fake pills are often cured as effectively as if they had taken the proper medicine Joseph Brean - The National Post Thursday, November 06, 2003 MONTREAL - Canadian scientists are set to launch a controversial series of experiments to explain, and ultimately exploit, the mind's apparent ability to heal the body with the help of a spoonful of sugar. On orders from Health Canada, six new research projects are to be launched next year to examine why sugar pills, sham surgery or the simple power of suggestion is often enough to ease the symptoms of diseases from insomnia and depression to Parkinson's and arthritis. The scientists leading the studies -- on sleep, pain, brain function and clinical trial design -- believe an understanding of the placebo effect will lead to improvements in the delivery of real medication, but the path to this knowledge winds through an ethical minefield. Placebos, from the Latin for "I shall please," are fake medications, usually sugar pills or saline solutions, given to some patients in drug trials as a benchmark by which to judge the reactions of patients taking the real medicine. Strangely, researchers have found time and again that placebos seem to heal just as well. The desire to exploit this phenomenon is not a new one. Knowing how mere belief in a phony cure leads to a real one could revolutionize much of medicine. But 50 years of study has failed to turn up a single psychological trait that underlies a person's susceptibility to this trickery. Recently, a sweeping review of drug trials cast doubt on whether the placebo effect even exists as anything more than a statistical quirk. Even if it does, though, many doctors argue it is never ethical to deceive sick people with phony cures. Opponents of placebo use point to suicides among the mentally ill as one of the gravest dangers of withholding effective medicine in the name of science, and argue that new treatments should be tested only against other effective ones. The moral quandaries posed by placebos have shifted in recent years as evidence of their mysterious power has grown. Inexplicable improvements have even been observed in arthritic patients who received placebo stab wounds instead of knee surgery. Ever since the recent discovery that placebo anaesthetics prompt the brain to make its own pain killers, which suggests placebos have physiological as opposed to simply psychological effects, debate between the two camps has reached a fever pitch. "People are tearing their shirts," said Dr. Gilles Lavigne, a professor of oral medicine at the Université de Montréal and a co-leader of the new research effort, which arose out of a Health Canada request to fill the void of Canadian research on the topic. It was a strange request. Just five years ago, Canada's own scientific guidelines forbade the use of placebos in most research. They could be used only if the condition was so minor that treatment was commonly refused, or if standard treatment was unavailable, either because it did not exist or there was widespread doubt about its effectiveness. Now the rules have changed somewhat, and refer only to maintaining the relationship of trust between doctor and patient, which is based on the patient's "free and informed consent." Whether this relationship is broken when a patient consents to being deceived, as they will be asked to do in the new studies, is an open question. The scientists working on the project, known as a New Emerging Team or NET, will launch their studies with a $1.2- million grant over five years from the Canadian Institutes of Health Research. This is not expected to cover all costs; preliminary results will be used to apply for longer-term support. The projects aim to gauge how important a patient's expectations are to the efficacy of treatment, primarily for sleep disorders and chronic pain. The key moral difficulty is that many of these expectations will be intentionally manipulated and based on false information given to patients by their doctors. The 25 members of Placebo NET gathered for their first strategy meeting last weekend at a Montreal airport hotel. Discussion centred on the contentious belief that the placebo effect is a crucial part of all healing practices. "Within the medical field, there is a recognition that it's not just the drug one gives [that heals], but it's a drug delivered within the context of an effective health care provider/patient relationship. Maybe surgeons might have an issue with this, but most physicians will not bristle at that," said Dr. Leora Swartzman, an associate professor of psychology and medicine at the University of Western Ontario and a co-leader with Dr. Lavigne. Knowing what factors lead people to heal themselves when given a dummy treatment would bring the risks and benefits of real treatments into sharper focus, and help doctors minimize the harsh side-effects of many drugs. It might also change how doctors deliver medicine by bringing an aspect of chicanery into their daily practice. It's a fine ethical line, since trust is an important component in medicine, "but it's worth pursuing because the payoff is so great if we can figure this out," Dr. Swartzman said. For centuries, the success of Western medicine was nothing more than the placebo effect in action. If patients got better after visiting a medieval doctor, for example, they did so in spite of all the leeches and bloodletting. If they healed at all, it was because they willed it. These patients did not know they were wishing for the impossible, and this is the placebo's frustrating philosophical legacy. To work, a placebo requires the patient's false belief. A cartoon nicely sums up this medical pickle. A coroner stands over a corpse, consulting his notes with the chief of police. "Overdose, Chief," he says. " He was with the placebo group, so we're pretty sure he only thinks he's dead." One imagines that, had he not overdosed and instead survived the treatment, the poor man would only think he was cured. For years, this was the common understanding of the placebo effect. Desperate patients put such faith in their doctors that they could drink any snake oil and believe it was easing their pain or helping them sleep. But the rise of randomized drug trials threw a wrench in the works. How could it be that patients who received placebos not only felt better, but sometimes experienced demonstrable physical improvement? Jean-Paul Collet, an epidemiologist at McGill University and an expert in randomized clinical drug trials, says these questions cut to the heart of the differences between Eastern and Western medicine -- the role of the mind in healing the body. In Eastern medicine, placebos pose no contradiction, since all cures involve an often mysterious reconciliation between individual parts of the body and the whole. "They cannot separate, as we do, the body doctor from the mind doctor," Dr. Collet said. Western physicians, however, are reluctant to prescribe treatments without knowing exactly how they work on the body. This policy can be unnecessarily restrictive, he said, pointing to the prescription of citrus fruits to combat scurvy long before anyone knew about vitamin C. The important factor was that they worked. Leaps of faith are risky in medicine, though, and to modern science, the placebo effect is a seemingly insurmountable paradox. The Oxford Companion to Philosophy says the very idea "creates a bind which calls out for philosophical therapy." Mr. Roger Squires of the University of St. Andrews, the author of its entry on the topic, finds the concept offensive for its contradictions; knowing a pill to be ineffective, a doctor cannot rationally prescribe it and a patient cannot rationally take it. "How can someone who recognizes this fact be cured?" he asks. He is either joking or has missed the point. When a placebo works, patients have no idea what is happening. Doctors only realize after the fact; the "double-blind" requirement to keep drug studies free of bias means even they cannot know which patients are taking the real pills. Dr. David Freeman, a pharmacologist and member of the University of Western Ontario's medical ethics board, said Western medicine is "blinkered" to the possible benefits of using the mind to heal the body. To the classical Western medical mind, Dr. Freeman said, there is no real difference between placebo patients and those who receive no therapy at all. But evidence is mounting that the difference is vast. Bizarre as it sounds, some placebos seem to work better and better each year. A survey of anti-depressant trials from 1981 to 2000 showed that the placebo effect has been increasing steadily and significantly. The prevailing explanation is that the initial cultural skepticism about all antidepressants slowly turned to confidence, so patients in later trials expected the drugs to work, and they did. These expectations might be the active ingredient in the placebo effect. When expectations are high, even impossibly so as in the case of placebos or dime-store herbal remedies, patient response is almost invariably positive. The ultimate goal of the Placebo NET will be to understand the healing power of this confidence, and how to keep it high. In the studies, the directions to patients "will be very carefully worded to manipulate and shape response expectancies," Dr. Swartzman said. For example, a study of morphine will look at the pain relief reported by patients who receive either real morphine, a drug called benzetropine that does not relieve pain but mimics morphine's side effects, or a completely inert saline solution. The expectation is that the benzetropine patients will not know they have been fooled, and report better pain relief than the saline patients. Another study will examine whether expectations of pain relief persist when patients are sleeping. Dr. Patricia Morley-Forster, director of the University of Western Ontario's Interdisciplinary Pain Program, said there is a direct relationship between the intensity of medical treatment and the placebo effect. Patients who submit to placebo surgery, for example (the New England Journal of Medicine reported recently that patients whose arthritic knees had been cut a few times experienced just as much long-term pain relief as those who actually received arthroscopic surgery) have a stronger placebo effect than patients who are prescribed a placebo for a minor illness, like a cold. The key difference is expectation, which can be coloured by a patient's desperation and a by doctor's bedside manner, not to mention misinformation, Dr. Morley-Forster said. Learning how this trickery happens could change everything from the education of doctors to the design of their offices, their research methods, their communication with patients and even the colour of pills, Dr. Lavigne said. It could also bridge some of the theoretical gaps between Eastern and Western medicine. Far from a medical myth or a statistical quirk, "placebo is a good way to reconcile biology and psychology, to reconcile body and mind," Dr. Lavigne said. [log in to unmask] SOURCE: Canada.com, Canada / National Post http://tinyurl.com/u00d * * * ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn