REGINA – Canadians experts say they fear stories of miraculous results from a controversial new MS treatment could be more about the "placebo effect" than an actual breakthrough – fears given new credence by two discouraging new European studies.
"I appreciate what people are going through – living with MS can be a terrible thing and they are anxious to pursue any treatment possibilities, but that has to be balanced against ensuring that the treatment actually works," Dr. Jon Stoessl says.
Stoessl is a researcher with the Canadian Institutes of Health Research and the acting head of the division of neurology at the University of British Columbia.
He says patient expectations about medical treatments can affect their success rates. It’s a kind of mind-over-matter, dubbed the placebo effect.
He’s concerned the hopes of people with multiple sclerosis have been prematurely raised about the long-term success of Dr. Paolo Zamboni’s research, which suggests a connection between multiple sclerosis and chronic cerebrospinal venous insufficiency (CCSVI) – impaired blood drainage through the veins from the brain.
Zamboni and his colleagues published a study that suggests CCSVI might be corrected by unblocking the veins – called the Liberation Procedure.
Patients have reportedly been travelling to India, Poland and Bulgaria for the treatment, which can costs tens of thousands of dollars.
However, separate studies out of Germany and Sweden, published in the journal Annals of Neurology and reported on in Canada this week, raise questions about the connection between narrow blood vessels and MS.
The German study looked at 56 MS patients and 20 others as controls.
According to an abstract of the study published online, blood flow was normal for all but one patient.
While in no way ruling out the possibility the new treatment could be legitimate, Stoessl is sympathetic to patients’ impatience, but he’s worried many are travelling outside of Canada to get costly, yet unproven treatments.
Those concerns are echoed by Dr. David Spence, director of the Stroke Prevention and Atherosclerosis Research Centre at the Robarts Research Institute in London, Ont.
He said the worst-case scenario for the treatment would be similar to what happened with the laetrile or vitamin B17 treatment for cancer. The water-soluble compound, extracted from apricot kernels, was anectdotally touted as a cure for cancer – and is still available for sale on some websites today – despite the fact that studies in the 1970s debunked such claims as quack science.
"The problem is that testimonials do not qualify as evidence," he said.
"What we’ve got here is an implausible theory with no evidence that it’s true and no evidence that the treatment works . . . and unfortunate victims that are mortgaging their homes to go off to Bulgaria."
Having said that, he says going ahead with the clinical trials Saskatchewan has promised to conduct is probably the only realistic option, given the media attention paid to the liberation therapy.
"The public furor, the emotional maelstrom over this, is probably going to make it necessary for a clinical trial to be done," he said.
He said any such trial would need to be double-blind – so that neither the researchers administering the treatments nor the subjects know who is getting the real treatment and who is getting the placebo.
Stoessl’s latest research, which measured the placebo effect on patients with Parkinson’s disease, was published in this month’s Archives of General Psychiatry.
His study found expectations directly regulate the power of the placebo effect.
Typically, a patient receiving a placebo in a clinical trial is given a sugar pill, but it can be done in an open or a hidden fashion.
"When the person knows they’re getting a treatment versus them receiving it without knowing . . . there is a difference between the two and that difference would be explained by the placebo effect."
Stoessl’s study measured the release of dopamine in the brains of people with Parkinson’s disease.
"We manipulated expectations of receiving an active drug," Stoessl said. "We told them that they had a 25, 50, 75 or 100 per cent chance of receiving the active drug to relieve their symptoms. In each case, we gave them a placebo."
Patients in the 75 per cent group released a lot of dopamine into the brain. The others didn’t.
"We were looking at Parkinson’s disease, but certainly the placebo literature suggests that expectation has a profound impact on other conditions," Stoessl said.
He said some unpublished trials done with Parkinson’s patients showed placebo benefits lasted for as long as two years.
"The mechanisms may be different of course – we have no way of knowing that – but it’s a common and mistaken belief that the placebo effect is something that is very short-lived," Stoessl said.
Describing Zamboni’s study, Stoessl said: "I found the scientific rationale to be somewhat challenging to follow."
But he admits that throughout the history of medicine there have been examples where "we weren’t as smart as we thought we were."
"A great example of that is ulcer disease when it was suggested that this was due to an infection and everybody laughed," Stoessl said. "Now, a few short years later, that’s considered standard. Everybody accepts this."
– with files from Postmedia News
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