New research shows placebo effect the real thing
CanWest News Service
Wed 03 Aug 2005
Byline: Sharon Kirkey
Source: CanWest News Service
They were the ``no option'' patients, people with advanced heart disease who had used up all their bypass surgeries and who were running out of ways to stay alive.
But when they joined a study testing laser surgery and a heart drug that grows new blood vessels, remarkable things happened.
Their crippling chest pain improved. They had fewer angina attacks. They were able to exercise longer during a stress test on a treadmill. Sophisticated nuclear perfusion scans showed an improvement in blood flow to their hearts and heart function.
And they didn't improve for just a week, or two weeks or six months. They were still better two years later a result all the more incredible considering they received no active treatment.
Yes, a catheter was inserted into an artery and slowly pushed up to the heart. Investigators then went through all the motions of making the patients believe they were using a satellite-guided laser to drill holes into their heart muscle.
But the laser was never actually switched on. Another group of patients got ``sham'' injections of salt water, instead of a growth factor protein.
``We gave these patients big headphones, we played loud music and the only person who knew whether they were receiving X treatment or placebo was the operator who was not involved in their followup,'' says lead author Dr. Roger Laham, an assistant professor of medicine at Harvard Medical School in Boston.
The surprising study, published in this month's issue of the American Journal of Cardiology, adds to growing evidence the placebo effect not only triggers true physiological changes in the body, it lasts longer than thought.
``The traditional thinking was, `Well, the patient improves for a couple of weeks after you give them `treatment' because they have a better outlook on life, and then they kind of go back and regress to what they were,'' says Laham, an interventional cardiologist at Beth Israel Deaconess Medical Centre.
``What this study shows is, in fact, that is not the case. What does happen instead is that these patients improve, and their improvement is as sustained as the ones given active treatment.''
This is bad news for researchers and drug companies, who try hard to quash the placebo effect when testing new drugs in order to know how much of a medicine's effect is real.
But rather than stifle it, others are racing to mimic it. They're testing different genes, as well as endorphins and hormones that are elevated following a placebo response.
``It's a matter of about a year or two before we can isolate and dissect the placebo effect into its various components, and then we can give these components separately or together to help patients,'' Laham says.
In other words, they're looking for a drug to trigger an effect that is, by definition, drug-free.
``There is no role in medicine for deceiving patients,'' Laham stresses. Deceit, by any definition, ``is not very ethical'' and no licensing body would condone a doctor palming a ``pill'' made of sugar, starch or chalk off as real medicine.
``However, it's going to be important to see what is in this deceit, or what the placebo effect entails. I'm certain there are certain physiologic effects that do occur. We're only just starting to scratch the surface.''
U.S. researchers are already testing placebos in the treatment of children with attention-deficit disorder, and in adults with autoimmune diseases such as lupus.
In fact, depending on the drug and the sickness involved, placebos inert substances that contain no active substances do as well, or better, in anywhere from five to 82 per cent of patients studied. Conditions that respond to placebos include coughs, colds, bronchitis, asthma, herpes, duodenal ulcers, irritable bowel syndrome, congestive heart failure, rheumatoid arthritis, post-operative swelling, pre-cancerous polyps of the colon and warts.
Kingston, Ont., urologist Dr. Curtis J. Nickel has shown more than half of men taking a placebo in his trial testing a treatment for non-cancerous enlargement of the prostate gland not only felt better, they experienced faster urinary flow.
One theory is their positive expectations lead to a relaxation of the smooth muscle in the bladder, prostate and urethra. The men on the make-believe medicine even complained of side-effects such as nausea, diarrhea, constipation and diminished sex drive.
Perhaps nowhere is the placebo response more confounding than in psychiatry. A paper published three years ago entitled The Emperor's New Drugs based on data submitted to the U.S. Food and Drug Administration for approval of the six most widely prescribed antidepressants found about 80 per cent of the response could be due to the placebo effect.
Eighteenth- and 19th-century doctors dispensed bread pills, coloured water and ``powders made of hickory ashes'' to their unsuspecting patients. Ancient Chinese texts also refer to a huge number of treatments that many medical experts today say were not going to be specifically effective, but worked best on those patients who were not ill.
More recently, three of five Israeli doctors and nurses surveyed said they used placebos in treating patients for everything from anxiety and asthma to vertigo, according to a study published last September in BMJ Online First.
Only one in 20 respondents felt placebos should be banned on ethical grounds. A 2003 survey of 772 randomly chosen Danish doctors found 48 per cent of family doctors reported using a placebo at least 10 times in the previous year typically an antibiotic for a viral infection to avoid a confrontation with a patient.
In the Israeli study, two-thirds of doctors and nurses who admitted to using placebos told their patients they were receiving bonafide medications.
Dr. Adrian Sandler, an adjunct associate professor in the department of pediatrics at the University of North Carolina, Chapel Hill, is part of a research team that recently enrolled 70 children with attention-deficit/hyperactivity disorder, age six to 12, into an innovative "placebo conditioning" trial.
First, the doctors determined each child's optimal dose of the stimulant, Adderall. Next, the children were randomly assigned to one of three groups: one stayed on the most effective dose for two months; a second got half the dose, while the third group got half the dose plus a placebo, an extra capsule.
``We told them that it had no active drug in it, that on its own that it would not be expected to have any effects on the ADHD symptoms, that we believed it be completely safe and have no side effects at all and that preliminary evidence showed there was a chance it might help some children with ADHD when taken along with the stimulant.''
In findings to be reported Sept. 26 at the Society for Developmental and Behavioral Pediatrics in San Diego, the team found the kids on the ``placebo conditioning'' arm maintained ``excellent'' control of their ADHD symptoms, Sandler reports, with far less of the nausea, stomach upsets and other side effects experienced by the kids on the higher doses.
``And they did markedly better as a group than those who went from the full dose to half the dose without the condition,'' added Sandler, medical director at the Olson Huff Centre at Mission Children's Hospital in Asheville, N.C.
He believes placebos could be used to minimize drug dosages and side effects in the treatment of depression, chronic pain, multiple sclerosis and other conditions for which people take drugs over the long term.
``We're trying to get the same drug effect with less drug,'' Sandler's collaborator, Dr. James Bodfish, professor of psychiatry at the University of North Carolina, told the Wall Street Journal.
No one knows exactly what's behind the placebo effect. One theory rests on the ``regression to means'' hypothesis essentially, that some patients eventually get better on their own, and that's what researchers are catching.
In addition, studies have shown that people who are spiritual, but not necessarily religious, improve even more on placebo.
``They believe in the treatment, they want the treatment to work, the treatment ends up working,'' Laham says.
But that doesn't explain all of it. In another yet-to-be-published finding, his team found the higher the technology promised, the more powerful the placebo response.
``If you bring them in and tell them, `I'm going to give you a pill,' the improvement is X. If you tell them, `I'm going to gave you gene therapy,' the improvement is 2X. Tell them, `I'm going to give you a laser using a satellite navigation system,' which is what we did, then the improvement becomes almost 3X.
``In other words, the more innovation, and the higher the patient's hope, the more improvement they get.''
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