tag:blogger.com,1999:blog-1394987738613999421.post7149658448358957147..comments2023-03-24T06:40:45.338-07:00Comments on Parkinson's Insights: Sham SurgeryRobin Elliotthttp://www.blogger.com/profile/10307317268932240843noreply@blogger.comBlogger4125tag:blogger.com,1999:blog-1394987738613999421.post-46609778035782227882010-08-31T19:16:35.177-07:002010-08-31T19:16:35.177-07:00@J - You bring up an excellent point - both the su...@J - You bring up an excellent point - both the surgeon and surgical team do <b>know</b> who received a real vs. sham operation. Clearly, by the very nature of what is involved with surgery, they will have to know. This is part of what makes it difficult to perform rigorous assessment of surgical interventions. So what typically happens then is that an entirely separate team is involved in the post-surgical care and assessment of individuals who are in surgical trials. That separate team is blinded to who has received a sham vs. real operation and the original surgeon is no longer involved.<br /><br /><br />@LindaH and @Peggy - This is a great conversation. One of the meeting participants and director of PDF's Research Center at Rush University, Dr. Christopher Goetz, <a href="http://www.neurology.org/cgi/content/full/71/9/677" rel="nofollow">co-authored a review</a> that delves into what they called placebo associated improvement. @LindaH points out that this improvement feels real to the person with PD, which is great for that individual. Indeed, as both @Peggy and I cite, there are measureable changes to brain chemistry. However, Dr. Goetz points out that the mechanism behind this improvement is likely not fundamental changes to the affected area, in this case the striatum, but involves a cortical or top-down change in neural activity. The result is that levels of many neurotransmitters, including dopamine, are altered. Dr. Goetz also noted that the more invasive the treatment (e.g., sham surgery) the more enhanced the placebo-associated improvement. <br /><br />I think the quote @Peggy provided from the recent Stoessl paper is very pertinent: <i>"The strength in belief of improvement can directly modulate dopamine release."</i> That statement underscores the difficulty in designing clinical trials in the face of the expectations that people (both people with PD and physicians) have towards a new invasive treatment-everyone wants it to work. So while there are many hurdles to finding new treatments for PD, I agree with you that belief should not be a prerequisite for success.Dr. James Beckhttps://www.blogger.com/profile/09276529867398575743noreply@blogger.comtag:blogger.com,1999:blog-1394987738613999421.post-31596742502403793382010-08-31T15:57:54.428-07:002010-08-31T15:57:54.428-07:00Oh,My! We must watch our use of words when speakin...Oh,My! We must watch our use of words when speaking of sham surgery and placebo effect. Quoting you:"The problem is the placebo effect works by convincing the individual something is real when it is in fact not... So while studying the mechanism underlying the placebo effect is a worthy vein of research, the placebo effect remains no substitute for medical therapy."<br /><br />I attended the NIH Sham Neurosurgical Conference and heard evidence (albeit little) that there IS a chemical change in the brain associated with placebo effect. In an article found on PubMed regarding the effects of expectations on placebo effect, it states: "Significant dopamine release occurred when the declared probability of receiving active medication was 75%, but not at other probabilities." and in concluding: " The strength of belief of improvement can directly modulate dopamine release in patients with PD. Our findings demonstrate the importance of uncertainty and/or salience over and above a patient's prior treatment response in regulating the placebo effect and have important implications for the interpretation and design of clinical trials."<br />Arch Gen Psychiatry. 2010 Aug;67(8):857-65<br />So you see, the placebo effect is very real.Peggynoreply@blogger.comtag:blogger.com,1999:blog-1394987738613999421.post-30390576150787544252010-08-31T15:57:28.730-07:002010-08-31T15:57:28.730-07:00I watched most of the first day’s webcast of the N...I watched most of the first day’s webcast of the NIH conference. Maybe the following was discussed elsewhere, but it seems most of the researchers at the conference believe that any improvement noted by the trial participants must be due to the placebo effect, and couldn’t possibly be due to the experimental treatment working<br />You wrote:<br />“The problem is the placebo effect works by convincing the individual something is real when it is in fact not.”<br /><br />Is it not possible that in open label trials , where improvement is often 30% or more that some of it at least is due to the treatment working? If a patient reports improvement in their symptoms, why should this not be considered “real” Many of us know PWP who have participated in trials (e.g. GDNF, Spheramine, fetal tissue transplant) and have experienced initial improvements and also lasting (5-10 years or more) benefits. There should be a way of including these patient reported outcomes in the clinical trial results. Currently they are just being ignored. They are real to us.<br /><br />From the segments that I did view, there seemed to be very little opportunity for patient input at this conference. It could have been different. At one point, one of the researchers was talking about the Spheramine trials being terminated and the effect on the participants. There was a phase I Spheramine trial participant in the audience – what a great opportunity that could have been to incorporate her experiences into the discussion. But she was not acknowledged in any way. <br /><br />I’m looking forward to seeing Day II. Hope it will be posted soon.LindaHnoreply@blogger.comtag:blogger.com,1999:blog-1394987738613999421.post-79927591044665826802010-08-24T10:15:14.753-07:002010-08-24T10:15:14.753-07:00This type of thing has been talked about with rega...This type of thing has been talked about with regard to acupuncture, etc. Sham surgery isn't really the equivalent of a double-blind study: while the patient may not know if the surgery was real or not, the surgeon performing the operation does know.<br /><br />To make things more parallel to a double-blind study, a surgeon who was not involved in the procedure would have to take over after the surgery was done and monitor recovery. He or she would then hand the patient over to the clinicians, who would be "in the dark" as to whether it was a sham surgery or not.Unknownhttps://www.blogger.com/profile/02151896375458529079noreply@blogger.com