Monday, December 19, 2011

The Ethics of Sham Surgery: Thoughts from a graduate student of neuroscience

I am on my way to become a scientist. In this phase of my life I am finding out how to, as one of our ethics professors puts it, “tease apart the fabric of the universe!” It is an interesting journey! The pursuit of science has taught us much through the millennia: how to build great monuments to the sky, how to heal our sick, what lies beyond the stars, what lies within our minds, etc. Scientists before me have expanded the scope of that which is accomplishable today. More so, they have shifted the views of our selves, of each other, and of the space in which we live. With such an impactful pursuit, it is incumbent upon any who would practice science to perpetually consider the effects of each contribution. Likewise, the public must be mindful of their role in guiding the arm of research—through public opinion, financial support, and the law—and develop thoughtful stances on the topics of the day.

Let’s consider this topic: sham human neurosurgery in the study of treatments for Parkinson’s disease (PD). Writer Alla Katsnelson examines this debate in a 2011 article in Nature [1]. For our purposes, let’s first take a broad view of the relevant questions, then explore the details presented by Katsnelson and other authors, and finally see if we focus in on an informed opinion about how we should guide the development of this variety of clinical intervention.

The scientific method is strong in its capacity to reach clear and reproducible conclusions. By this methodology, scientists first propose a hypothesis about some facet of the universe’s operation. Then, a complete (as far as is known) battery of tests is conducted which seek to invalidate that hypothesis. If this hypothesis is still standing after such test, then people accept that the hypothesis works as far as we know. Simple.

And yet, in the debate at hand, scientists have shown a reluctance to use every method to knock down proposed PD treatments. Specifically, there is a widespread unwillingness to conduct sham neurosurgeries on human volunteers in order to rule out the placebo effect. Many researchers see this type of test as unnecessary, saying that the informative benefits of sham surgeries do not outweigh the costs to volunteers who undergo highly invasive surgeries or to the financial bodies that afford the study. Sham surgeries involve, at minimum, anaesthetization, attachment of a surgical frame onto a patient’s exposed skull, and the drilling of a through-hole onto the patient’s dura mater (the protective, membranous covering around the brain). The act of enrolling extra patients, the theatrics of a sham surgery, data collection, and follow up significantly increases the costs of clinical trials—trials that routinely reach $10 million. Furthermore, since these factors limit the size of such studies, it has been proposed that the inclusion of sham controls adds little value statistically. In the UK, opinions of the unnecessary quality of sham surgeries are so strong that none have ever been performed.

On the other hand, how can any study that makes to call itself science neglect to find out if the treatment is any more effective than healing wrought from the placebo driven expectation that the surgery does work? Is it justifiable to approve a treatment whose sole effect stems from a patient’s faith in modern medicine? Treatments for Parkinson’s highlights this concern perfectly as a primary neurochemical generated by the positive feelings associated with the placebo effect is exactly the same chemical used in pharmacological treatments of PD, dopamine.

And are the costs really as high as they seem? Katsnelson sites that the most notable risk of sham surgery is that associated with the use of general anesthesia that can exacerbate the problems of failing muscle control over the lungs and heart. However, a 2002 study in the British Journal of Anesthesia indicated a range of anesthetics that, given the limited information available, are “probably safe” [2]. As for the cost and statistical considerations, is any expenditure or analysis worth anything at all unless all necessary tests of the hypothesis are conducted? What’s more, since clinicians agree to provide the real treatment to volunteers serving a sham controls if the treatment proves effective, the costs of serving as a sham control are lowered further still.

In a 2005 survey of members to the Parkinson’s Study Group, a non-profit organization of North American physicians and health care professionals experienced in PD care and dedicated to PD research, 97% of respondents affirmed that leaving these questions unanswered is unjustified [3]. For these 91 out of 94 clinician researchers, the usefulness of sham-surgeries over unblinded controls was nearly unanimously affirmed. Likewise, serious doubts were levied as to whether neurosurgical interventions for PD can be considered truly efficacious unless it has withstood the sham-control test.

As I grow as a scientist, I will be ever moved towards delivering as complete an answer as I can to the hypothesis at hand. If a treatment works, I will want to know why it works and will not be content to know that it simply does. That is my task as a scientist. Still, each member of the scientific community must always temper this desire to know with ethical methods. And though it is inherently off putting to place a patient seeking a cure through a faux treatment, the benefits of finding a suitable therapy for PD are, in my opinion, worth the additional medical risks and financial burden of sham control testing. And unless new developments shift the scales of this cost/benefit analysis away from the side of greater benefits, you will find me in support of the continued use of sham surgeries as controls in the clinical testing of therapies for Parkinson’s disease.

--Jacob Billings


Want to cite this post?
Billings, J. (2011). The Ethics of Sham Surgery: Thoughts from a graduate student of neuroscience. The Neuroethics Blog. Retrieved on , from http://www.theneuroethicsblog.com/2011/12/ethics-of-sham-surgery-thoughts-from.html


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