St. Joseph’s London among researchers looking into placebo effect

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Two St. Joseph’s researchers are among a group involved in a multi-year study of the placebo effect.

Placebo NET, or new emerging team, has been granted $1.2 million over five years by the Canadian Institutes of Health Research to conduct a study, Disentangling the placebo effect: The relative roles of pharmacology and response expectancy in sleep and pain.

Dr. Pat Morley-Forster, medical director of St. Joseph’s Health Care London’s and the University of Western Ontario’s Interdisciplinary Pain Program, and Dr. Frank Prato of London’s Lawson Health Research Institute, are associate member and core member, respectively, of the placebo NET. The team’s co-leaders are Leora Swartzman, UWO, and Gilles Lavigne, Universite de Montreal. (Other members at SJHC-LHRI are Dr. Keith St. Lawrence and Dr. Alex Thomas.)

The team – with 25 members in London at St. Joseph’s and the University of Western Ontario – includes researchers at six academic institutions from a wide range of disciplines/specialty areas. They include cognitive neuroscience, dentistry, psychology, psychiatry, neurology, anesthesiology, medical biophysics, nursing, sociology, anthropology, pharmacology and bioethics. The group held its first strategy meeting this fall in Montreal.

Morley-Forster and Prato will be working together as part of a group studying acute clinical pain – The relative roles of pharmacology and expectancy in post-surgical analgesia – one of six projects the team will undertake in an effort to better understand the placebo effect. Others participating in their study include Swartzman and Gary Rollman, also of UWO.

Placebos are inert substances used in drug efficacy testing as a control. The placebo effect is a change after a placebo is taken that has been attributed to the faith or expectations of the person who has taken the substance.

The researchers want to learn how the placebo effect influences the healing process. Previous studies have shown that expectations play a role in the effects of a range of substances, including alcohol, caffeine, THC and D-amphetamine. This is probably mediated through the body’s own natural pain-killing substances, called endorphins.

“There is a direct relationship,” says Morley-Forster, “between the intensity of medical treatment and the placebo effect. Patients who submit to placebo 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 by a doctor’s bedside manner, not to mention misinformation.”

Morley-Forster and Prato’s study of 80 adults undergoing specific surgeries will look at how this expectation accounts for the variance in post-operative morphine use. By adjusting a patient’s expectation of relief, they hope to clarify how much of the pain-relieving effect of a drug is due to its pharmacologic action and how much to the patient’s own release of endorphins. Neuro-imaging techniques will be developed to measure exactly where in the brain the pain reduction is occurring.

“To our knowledge,” says Morley-Forster, “this will be the first use of the balanced placebo design in a clinical trial, as opposed to a laboratory study with healthy normal individuals.”

Pain research has been the largest source of data on the potency of placebo effects. Chronic pain affects 29 per cent of Canadian adults, with major social and economic impacts. About 15 per cent of adults in Canada report moderate to severe pain, and two-thirds of these patients complain of poor sleep quality.

These findings have important implications in the design of clinical trials to assess the effectiveness of potent new analgesic agents developed by the pharmaceutical companies. For example, the influence of a person’s expectation of superior pain relief from a new and widely promoted analgesic agent could lead to the erroneous conclusion that this new drug is superior to existing treatments when it is, in fact, only equivalent or wore.

In one British study of people taking over-the-counter analgesics for headache, the branded drugs did better than the unbranded, while the branded placebo performed better than the unbranded placebo!

Contrary to popular belief, all humans and not just a susceptible minority are potential placebo responders. Doctors and other healers may be able to harness the placebo effect once it is understood to be a natural healing power and not just a trick to be played on the weak-minded.