Help proving placebo effect.

[Professor Yaffle]

Yeah, I think it helps to force people to be specific when examining these claims. Otherwise people can gloss over issues like "the baby is still hungry".

Medical research tends to be concerned with a hierarchy of the 5 D's - in order: Death, Disability, Disease, Discomfort, Dissatisfaction. Something that affects dissatisfaction or discomfort without addressing disease or disability is seen as relatively undesirable from a medical perspective. But from an individual perspective, it is the discomfort or dissatisfaction that impacts their quality of life.

Linda

The thing is though that these boundaries can be very blurred. For example take the case of depression, which is often very amenable to the placebo effect. Where the biological and psychological are inextricably linked, a placebo could possibly significantly affect mortality (from suicide as a result of depression). Some research suggests that the majority of the effect of an anti depressant comes from its power as a placebo with smaller effects coming from its specific chemical nature. I know this is veering OT, but I do find the link between the biological and the psychological fascinating.

 

[Ivor the Engineer]

I've been trying to think of placebo treatments that affect things like stress hormones but each time I've thought it through there are always physical changes in behaviour or the treatment could be considered “active” in the sense that the patient is thinking differently, thus the activation of their sympathetic and parasympathetic nervous systems are different as well as brain chemistry.

It seems as soon as the mechanism of how a placebo effect works is discovered it should not be considered ‘placebo’ anymore, rather just that ‘this effect occurs when you think or behave in this way.’

E.g. I get worked up arguing with people on this forum and my heart rate goes up. I clear my mind and focus on relaxing and my heart rate goes down.

 

[JoeTheJuggler]

I think I mentioned several times that there do seem to be effects specific to placebos, so I agree with you. I just get the impression that you think we disagree on something, but I'm not clear on what it is.

I suspect we're using different notions of the term "placebo effect". I've always thought it was a term to do with experimental design.

You seem to think it's possible to test FOR a placebo effect. In the nature of experimental design, the placebo group is not what your testing for.

In my example where you're testing the efficacy (or safety or whatever) of a drug. You've got a no-treatment control group, a control group (that gets a glass of water an an pill that mimics the drug except for the active ingredient), and the treatment group (that gets the drug and a glass of water). After the test you notice a big placebo effect (i.e. the difference between the non-treatment group and both of the other groups is marked).

So you want to see what's going on, and you suspect the water has something to do with it. You set up a new design to test for that, and now the glass of water IS the treatment group. If you're testing for it, then it's not the placebo effect.

 

[fls]

I suspect we're using different notions of the term "placebo effect". I've always thought it was a term to do with experimental design.

You seem to think it's possible to test FOR a placebo effect. In the nature of experimental design, the placebo group is not what your testing for.

In my example where you're testing the efficacy (or safety or whatever) of a drug. You've got a no-treatment control group, a control group (that gets a glass of water an an pill that mimics the drug except for the active ingredient), and the treatment group (that gets the drug and a glass of water). After the test you notice a big placebo effect (i.e. the difference between the non-treatment group and both of the other groups is marked).

So you want to see what's going on, and you suspect the water has something to do with it. You set up a new design to test for that, and now the glass of water IS the treatment group. If you're testing for it, then it's not the placebo effect.

Let me try to clarify what I mean (and what gets referred to in the medical literature).

A study will consist of two groups that are treated exactly the same except that one group will receive an active treatment and one group will receive a dummy treatment (let's assume for now that we're talking about pills, because that is how the idea originated) called a placebo. Any changes that happen in the placebo group are effectively subtracted from any changes in the treatment group, and if there are any additional changes left over, that is referred to as the treatment effect.

Any changes that occur in the placebo group will be due to various effects that have already been mentioned. However, it has been assumed that some of these effects may be due to the placebo itself - that the idea of receiving a treatment leads to changes that are wrought by the mind. So placebo effect most properly refers to effects solely due to the effect of placebo - i.e. if two groups were treated exactly the same except that one group received a dummy pill and one did not, any changes in the non-placebo group would be effectively subtracted from the placebo group, and if there are any additional changes left over, that is referred to as the placebo effect.

However, since the original purpose of most research involving a placebo has not been designed to study the placebo, but rather the treatment, most placebos have not been compared to no treatment. And so with rising interest in the placebo effect, conclusions have been drawn from inadequate information. For example, assumptions have been made that the bulk of any change in the placebo group is due to the placebo effect. And much has been made of this by those that are interested in mind-body interactions. If we are truly interested in studying the placebo effect (i.e. effects solely due to the presence of a placebo), then studies need to be designed differently. And the meta-analysis that I referenced earlier looked at this issue specifically. It demonstrated that the placebo effect seemed to make no difference to objective measures of healing/cure/change, and did make a difference to subjective perceptions and pain.

There are three things that are sort of being used interchangeably and that is what is confusing, I think - the placebo group, changes that occur within the placebo group due to various effects, and changes that occur solely due to the presence of a placebo treatment. So when I say that the placebo effect does not represent a healing effect (in response to the OP that used the term "healing effect" when referring to homeopathy), but rather an effect on subjective perceptions, I am referring solely to effects due to placebo treatment.

Linda

 

[fls]

The thing is though that these boundaries can be very blurred. For example take the case of depression, which is often very amenable to the placebo effect. Where the biological and psychological are inextricably linked, a placebo could possibly significantly affect mortality (from suicide as a result of depression). Some research suggests that the majority of the effect of an anti depressant comes from its power as a placebo with smaller effects coming from its specific chemical nature. I know this is veering OT, but I do find the link between the biological and the psychological fascinating.

I agree.

Linda

 

[Apathia]

And I'd like to qualify my statements just a little.
There does appear to be a fuzzy area in this in which reducing stress and having a hopeful attitude aid recovery from illness and injury.
The extent of this as far as research I've seen is marginal. You get the stories of people who have battled the cancer with good humor and had remarkable recoveries. I don't wish to throw ice cold water on their inpirational experiences, but there are also people who haven't recovered from cancer, but have nevertheless met death positively.
Faith, hope, and a Robin Williams movie are good things but they don't yeild the consistant results we expect of medicine. In a some cases they seem to hasten recovery in conjunction with effective medical treatments, but you can't realy count on "miracles" anyway.

The person who is taking the doctor's age old advice to rest and is in a postive frame of mind that encourages cooperation with actual medicine, certainly does stand a better chance of benifiting from the treatment. And taking it easy lets the body attend to the recovery, rather than to fight or flight. That's all I see to it.

Linda wrote:

Medical research tends to be concerned with a hierarchy of the 5 D's - in order: Death, Disability, Disease, Discomfort, Dissatisfaction. Something that affects dissatisfaction or discomfort without addressing disease or disability is seen as relatively undesirable from a medical perspective. But from an individual perspective, it is the discomfort or dissatisfaction that impacts their quality of life.

Yes, personally we'd like to see our Discomfort and Disarisfactions, a emotional issues addressed. It's OK to aim for a holistic attitude about our health. The problem is again and again is when a temporary pain killer fix is substituted for medical attention that corrects the cause. This happens not just in the quack context.

And of course, for many things, there aren't cures. So for the time being we take something to ease the discomfort.

I flunked Calculus in college (The shame!), but I passed Renal Calculus a few years ago. Since ultrasound wasn't avalable to me to blast the stones into smaller pieces, I just had to grin, grimace, and let nature take its painful course through the urinary track. I was doing studies at the time and didn't want to use the narcotic pain killer the doctor prescribed. I survived it well on Advill and Reiki. I'd take the Advill and it would only reduce the pain a certain amount. Then a friend would give me a Reiki session and the pain would be in most cases gone. Two things here: Pain is subjective. Secondly some of the pain was muscular due to contractions of lower back muscles. The Reiki would relax the muscles. It complemented the Advill. It helped ease my discomfort. But it didn't make those stones pass through any faster.
(NB! In using Reiki as an example, I am not recommending it as any sort of curative!)

 

[Professor Yaffle]

Research into optimism and cancer survival

http://www.medicalnewstoday.com/medicalnews.php?newsid=5780

I haven't read the original study, so I can't speak for its quality, but it does make one rethink what is taken for granted about a positive attitude. I am sure there have been other studies with similar results. Someone else might have better info on this.

Edit - just found this report too, mentioning more mixed results

http://news.bbc.co.uk/1/hi/health/3481605.stm

And some other random links on the subject that you might be able to find original research from

http://www.hsph.harvard.edu/press/releases/press11212001.html

http://www.corexcel.com/html/body.humor.page5.htm

http://cat.inist.fr/?aModele=afficheN&cpsidt=1970518

 

[Ivor the Engineer]

A far more mundane explanation for why optimistic people survive longer is they take better care of themselves. A pessimistic person is likely to conclude ‘what’s the point in looking after myself if I’m likely to die in X months?’ having been given the news they have a serious / terminal illness.

 

[Ivor the Engineer]

<snip>
There are three things that are sort of being used interchangeably and that is what is confusing, I think - the placebo group, changes that occur within the placebo group due to various effects, and changes that occur solely due to the presence of a placebo treatment. So when I say that the placebo effect does not represent a healing effect (in response to the OP that used the term "healing effect" when referring to homeopathy), but rather an effect on subjective perceptions, I am referring solely to effects due to placebo treatment.

Linda

I'll agree with that.

 

[Cuddles]

Asthma is believed to be a (partly) psychosomatic illness so by definition it should be susceptible to placebo effect.

Asthma is not psychosomatic. The main reason for the apparent huge rise in asthma incidence is that most people now diagnosed with asthma do not have anything wrong with them. In these people the problem is purely psychosomatic, so placebo could have an effect. In people, like myself, who actually have asthma the difference between placebo and treatment can be the difference between life and death.

In recent acupuncture tests they did a mock acupuncture (fake needles that felt the same as real ones) as a placebo. Any effect this had (compared to no treatment) were equal to the test group (real acupuncture). What caused the effect? We don't know, but we can say that it wasn't the treatment (using real needles). Maybe lying down in a certain posture during the treatment sessions alleviated back pain. Or maybe it was something to do with perception and reporting of pain as a subjective measure. We simply don't know.

Unfortunately almost all this research is flawed. Fake acupuncture needles have been used as placebo for a long time, but recent research shows that there are major differences between real and fake needles. Even in recent studies of specially designed placebo needles, rather than simple retracting ones, there are still very clear differences between them.
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Abstract&list_uids=9717924

FINDINGS: Of 60 volunteers, 54 felt a penetration with acupuncture (mean visual analogue scale [VAS] 13.4; SD 10.58) and 47 felt it with placebo (VAS 8.86; SD 10.55), 34 felt a dull pain sensation (DEQI) with acupuncture and 13 with placebo.

In addition, not only is it possible to tell the difference between real and placebo needles, but it also seems that fake needles are not completely inactive, and so may not be valid as placebos at all.
http://www.superdragon.co.uk/acupuncture knowledge/placebo acupuncture needles.htm

The fact that more than a third of patients treated with the placebo needle experienced de qi did raise some concerns among the scientists, who said that the results of their experiment "· call into question the main claim of placebo needles that they only are eliciting a placebo response." To avoid producing the de qi response, they proposed that future studies use non-acupoints for placebo needling.

It is interesting to note that most of the studies I have seen on this subject conclude that placebo needles are valid, even when there are obvious differences between real and fake needles. My interpretation of their results certainly does not agree with their conclusions. It is even more interesting that despite all the questions over placebo needles, no studies can find a difference between real and placebo acupuncture.

 

[Professor Yaffle]

I can't agree with that re asthma. I think people just have different triggers as to what sets their asthma off. I most certainly have asthma, triggered by animal allergies, cold air, respiratory infections, smoke and hairspray. I very rarely get an attack because I avoid those triggers which are avoidable. But I do also get wheezy sometimes if I am very anxious about something.

I think the increase in diagnosis is down to better recognition by doctors. Again by personal experience, I have had asthma since I was a baby, but wasn't diagnosed by my fairly elderly GP who said I had "wheezy bronchitis" (very frequently). When I saw a new and younger GP at the age of 12 he diagnosed me correctly and expressed amazement that given my history I hadn't been diagnosed before. I think in the past, asthmatic kids were just told they had a "weak chest".

 

[Baron Samedi]

(snip)

However, since the original purpose of most research involving a placebo has not been designed to study the placebo, but rather the treatment, most placebos have not been compared to no treatment. And so with rising interest in the placebo effect, conclusions have been drawn from inadequate information. For example, assumptions have been made that the bulk of any change in the placebo group is due to the placebo effect. And much has been made of this by those that are interested in mind-body interactions. If we are truly interested in studying the placebo effect (i.e. effects solely due to the presence of a placebo), then studies need to be designed differently. And the meta-analysis that I referenced earlier looked at this issue specifically. It demonstrated that the placebo effect seemed to make no difference to objective measures of healing/cure/change, and did make a difference to subjective perceptions and pain.

Agreed. Most tests are along the lines of:
A: Drug
B: Placebo

So hence you can't test the effect of Placebo vs. do nothing. I thought that there have been studies done with the full range of control groups, such as:
A: Drug
B: Placebo
C: No action
D: No action with positive spin (you don't need pills since it's nothing)
E: No action with negative spin (I can't give you anything since it's too serious. Let's send you to a "specialist")

I guess not too many people have looked into groups D and E. That would really be awesome if they could (damn lawsuits)...

 

[Ivor the Engineer]

Agreed. Most tests are along the lines of:
A: Drug
B: Placebo

So hence you can't test the effect of Placebo vs. do nothing. I thought that there have been studies done with the full range of control groups, such as:
A: Drug
B: Placebo
C: No action
D: No action with positive spin (you don't need pills since it's nothing)
E: No action with negative spin (I can't give you anything since it's too serious. Let's send you to a "specialist")

I guess not too many people have looked into groups D and E. That would really be awesome if they could (damn lawsuits)...

The NHS does (E) all the time. You're told you need an operation then they put you on a 12 month waiting list and keep shifting the dates.

 

[Mr. Scott]

Now, I thought that this "placebo effect" was something quite proven, but I can´t find references to rebate Carlos.

There was a study in the news a few months ago (that I can't find right now in google searches) that compared different types of placebos for their relative effectiveness. The comparison was between pills and acupuncture. The pills were impressive-looking and inert. The acupuncture was with trick needles that looked like they were going in the skin but actually the point retracted inside the needle, like a stage knife where the blade telescopes into the handle.

The fake acupuncture relieved pain quite a bit better than the fake pill.

In my recollection of articles, the placebo effect is geatest with conditions "in the mind," with pain, and has some effect to lower stress with its well-known physiological benefits like improved immune response.

I have not yet heard a case of a placebo restoring a lost limb, so more tests are called for.

 

[Apathia]

There was a study in the news a few months ago (that I can't find right now in google searches) that compared different types of placebos for their relative effectiveness. The comparison was between pills and acupuncture. The pills were impressive-looking and inert. The acupuncture was with trick needles that looked like they were going in the skin but actually the point retracted inside the needle, like a stage knife where the blade telescopes into the handle.

The fake acupuncture relieved pain quite a bit better than the fake pill.

In my recollection of articles, the placebo effect is geatest with conditions "in the mind," with pain, and has some effect to lower stress with its well-known physiological benefits like improved immune response.

I have not yet heard a case of a placebo restoring a lost limb, so more tests are called for.

In my opinion the edge Acupuncture has in pain relief is in it being physical attention. Unless a touch is threatening, we all react favorably to personal contact. Endorphins and hormones and certainly a reduction of tension.

 

[Ivor the Engineer]

In my opinion the edge Acupuncture has in pain relief is in it being physical attention. Unless a touch is threatening, we all react favorably to personal contact. Endorphins and hormones and certainly a reduction of tension.

You obviously haven't spent enough time on public transport