A number of times our class has discussed issues in
translating model animal research into human trials and logistical or ethical
issues that arise in the process. Sham surgeries are often used to study
surgical interventions in animal studies and involve performing all of the experimental
procedures except actually administering whatever treatment or drug is being
tested. Such a procedure removes bias from the experiment and helps
investigators to identify what effect the treatment itself is having since the
sham provides information on what the physical effects of the procedure rather
than the drug/treatment might be. During our discussion of stroke, the question
of sham surgeries in human trials was brought up; understandably some people
thought it unnecessary or even cruel to subject a patient to the risks of surgery
if they weren’t receiving treatment. Sham surgeries have been used to test a
number of Parkinson’s disease treatments (particularly in the US) and have sparked
controversy between investigators too. An article from Nature in 2011 talked about this debate over the use of sham
surgeries, the nature of the placebo effect (a perceived improvement in a patient
who is not receiving the experimental treatment) in Parkinson’s research, and
various treatments being pursued. The article brings up a number of interesting
considerations for using sham surgeries in Parkinson’s research including the
fact that the placebo effect is mediated by dopamine (which Parkinson’s
patients do not have enough of) and therefore is not necessarily something
undesirable for control patients. Sham surgery is used for the exact reason
that the placebo effect can be removed from the results of any study by using a
placebo (the sham surgery) to determine the baseline against which the experimental
results are compared: however, when group assignments are finally revealed and
the placebo effect is removed, this can be physically devastating to patients
who did not receive the experimental treatment. Suggestions for alternatives to
sham controls include comparing an experimental treatment with an approved
therapy like deep brain stimulation, or having all patients receive the
experimental treatment and then be assessed by raters who do not know the
status of the patient within the study. The reasoning behind replacing sham
surgeries in the context of Parkinson’s research is that some people think they
may have prematurely stopped investigations into promising therapies. What do
you think about the use of sham surgeries in clinical trials for Parkinson’s
research? Do you see merit to either side of the debate?
Katsnelson, Alla. "Why Fake It?
How 'Sham' Brain Surgery Could Be Killing Off Valuable Therapies for
Parkinson's Disease." Nature 476
(2011): 142-44. Web. 19 Nov. 2014.
That’s an interesting post! I never thought of the placebo effect messing with trials. It makes sense though, if there is a placebo effect it would be difficult to know if the treatment is working. The problem is when the treatment actually is working! With something as serious as Parkinson’s and a treatment as serious as surgery I would like to see a different methodology for trials. I like the idea of comparing an actual therapy to another therapy.
ReplyDeleteComparing proposed therapies to established ones is something that later stage clinical trials often do as part of proving the effectiveness of their treatment, which I also prefer to using sham controls. I like that patients receive real treatment and the placebo effect is still eliminated using this study design.
DeleteGreat post and interesting questions. After some thought I feel like sham surgeries on humans are a valid, but still controversial, way to conduct a clinical trial. From my understanding, many times patients actively seek out opportunities to be involved in new treatments, especially with a debilitating disease such as Parkinson's. Since the patients elected to be involved in the study I dont see any problem with some of them being given the sham surgeries. They would have had the risk of the surgery anyway and they are involved in developing a possible treatment for themselves in the future.
ReplyDeleteOne thing I do like about sham surgery protocols is that some have provisions which give a control patient access to the experimental treatment if it is found to be effective. I'm not sure if the patient has to wait for full FDA approval of the new treatment before receiving it, but this seems like a good practice to help control patients in return for their participation.
DeleteI'm kind of on the fence in regards to sham surgeries. To me, it sounds like the purpose of the sham surgeries is to gain more knowledge and understanding of the human body and what the "baseline" is. So it reminds me of the times when the jews would be subjected to experimentation under nazi control and of Unit 731 when the Imperial Japanese Army did the same to the Chinese. But as stated earlier, I'm on the fence in that if unforced consent is given, then it is by the volunteering patients' choice to undergo the surgery. And I know that the sham surgeries and the experimentations done in the past are not one and the same. And that to compare the two situations is a bit exaggerated but we all know that there is a fine line when it comes to giving consent while fully aware and giving consent in ignorance. Thank you for the article though. It made me think about my bioethics class that I took last semester, hahaha.
ReplyDeleteI am one of those individuals that tend to find sham surgeries more on the cruel side. It is true that many people would elect for these experiments because their medical condition is so severe that they would basically try anything to alleviate their symptoms to the slightest degree. I think a lot of times we think "Oh they signed off on it so its fine". But many people don't really know what they're getting themselves into; not everyone has a medical background so all patents hear is that there is a potential study that might help and thats all they need to know when they struggle so much day in and day out. I question if sham surgeries can alternatley have a negative effect on a patient after they found out they didn't receive the treatment. What happens when a person finds out they weren't cured for anything, but went through the motions Are they affected psychologically or physiologically. Are there changes in certain hormones or depression? After seeing a previous post on deep brain stimulation and how effective that surgery is for Parkinson's patients , I would elect that comparing various therapies would be the most beneficial.
ReplyDeleteThanks for giving us your opinion! My experience working with clinical trials has made me a lot more comfortable with patient consent; every research nurse I have worked with makes sure their patients understand exactly what the trial will entail and the nurses are upfront about the possibility that the patient may be in a control group. The studies I've worked on have all been comparing current standards of care to new drugs though, so I feel like being this open and honest is a lot easier - we can assure patients that they will receive the best care possible regardless of their status in the study because they are being treated in either group.
DeleteWell done! I like the conflict highlighted here: sometimes best practices in clinical care conflict with best practices for controlled physiology experiments. How we deal with this ethical problem speaks a lot about our priorities as humans. This particular case is complicated by the placebo effect operating on a pathway associated closely to the disease.
ReplyDeleteGreat unbiased breakdown of a very controversial topic! There is no doubt that the placebo effect has the potential to work, which would lead one to believe that sham surgeries may be effective in certain situations as well. Depending on the scenario I believe a sham surgery could be effective, or it could have a miserable outcome. It appears that in surgeries used to treat debilitating conditions, sham surgery can have a positive impact. This is probably because these debilitating conditions cause pain, but usually don't fully impair overall function. For example, debilitation of the meniscus over time can lead to tears that cause pain in the knee, but rarely ever fully inhibit movement. This pain can be treated with a placebo, as shown in sham surgeries. An example of a situation where I don't think a sham surgery would work would be a surgery to repair a severed artery. This is because an actual physiological function that is required for life (the flow of blood) is being impaired.
ReplyDeleteI definitely think the context is important in determining whether or not sham surgeries are appropriate for a particular study. Great issue to bring up!
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