Simon Wessely on Multiple Chemical Sensitivity (MCS): "related to expectations and beliefs"

[Laelia]

I thought this might be of interest to some, not sure if it's been posted before (it's from February 2007):

Memorandum by Professor Simon Wessely, King's College, London

I am not an allergist, nor an immunologist. I am an epidemiologist, interested in the distribution and causation of illness, and a psychiatrist, interested in the social and psychological aspects of illness. I directed a unit at King's College London that has studied many aspects of chronic fatigue syndrome and related unexplained illnesses such as "multiple chemical sensitivity" (MCS) 44, and I now direct a unit that researches many aspects of military health, including Gulf War illnesses. I have published over 500 professional original publications on these subjects.

We recently published a review of 37 "provocation" studies in which MCS sufferers were exposed to various stimulants in controlled conditions. The conclusions were that "persons with MCS do react to chemical challenges: however, these responses occur when they can discern differences between active and sham substances, suggesting that the mechanism of action is not specific to the chemical itself, and might be related to expectations and beliefs" (J Allergy Clin Immunol 2006: 118: 1257-1264).

This supports the strong consensus amongst clinical and academic immunologists that the phenomenon of multiple chemical sensitivity cannot be explained by allergy and/or immunological mechanisms (in contrast for example to allergic reactions to single substances such as peanuts). On the other hand, there is convincing experimental evidence that this can be explained by psychological conditioning, in which exposure to a stimulus such as an unpleasant odour becomes associated with a physiological reaction. The fact that symptoms develop only when the person is consciously aware of the stimulus (as opposed to peanut allergy for example) and that in double blind controlled tests these reactions cannot be reliably reproduced, speaks strongly to a conditioning model. Social, cultural and psychological factors related to perceptions of risk further amplify these reactions. I am not saying, and do not believe, that these symptoms are imaginary or "all in the mind", but I am saying that social and psychological factors have more explanatory power than immunological or allergic factors.

Why does this matter? Considerable evidence shows that many (but not all) diagnoses of MCS are in reality misdiagnoses of other, often fairly straightforward, conditions such as depression or anxiety. A label of MCS not only means that such people then do not receive appropriate evidenced based successful treatments, but may instead receive treatments that do little good and in some cases considerable harm. I have in the last 20 years as a consultant seen a number of unwell patients who have received a diagnosis of MCS. So far this has only come from the private "alternative allergy" or "clinical ecology" sector. For some this has had unintended, but serious consequences for both health and bank balance. For me these have been some of the most distressing experiences of my clinical career.

44 "Multiple chemical sensitivity" has become a popular term, it would still be more appropriate to talk about chemical intolerance rather than sensitivity. MCS is not recognized in the WHO International Classification of Diseases. [My bold]

https://www.publications.parliament.uk/pa/ld200607/ldselect/ldsctech/166/7022111.htm

 

[hixxy]

I wouldn't have expected anything different from him.

 

[duncan]

If Norman Mailer had a love child with Art Garfunkle, do you imagine the result would be a professor at Kings College, London?

 

[Old Bones]

"Memorandum by Professor Simon Wessely, King's College, London

. . . The fact that symptoms develop only when the person is consciously aware of the stimulus . . . speaks strongly to a conditioning model."

That has definitely not been my experience, and especially not when my sensitivities were at their worst during the early years. Within minutes of entering the front door, I was able to tell if a friend or family member had brought a new, unsafe (toxic) article into their home since I was last there -- even if it was small and located in the basement (hence unseen).

And years later, both my husband and I experience symptoms (burning eyes, sore throat and headache) from the scented laundry products wafting out of the neighbours' dryer vent before we notice the smell.

 

[Gingergrrl]

Is it bad to want to punch him in the face after reading this? My mast cell doctor (who actually IS an allergist and immunologist) explained to me that MCAS is NOT an IgE mediated reaction (like the peanut allergy analogy) and in the case of reactions to smells (whether to food, cleaning products, VOC's, perfume, etc) the smell goes through the nose into the limbic system in brain and lodges there and continues to increase vs. dissipate like for a normal person. He said many patients can get anaphylaxis from a smell alone and must wear a breather mask. He assured me it was very real and for some can be life or death.

 

[Hip]

Simon Wessely may have got it wrong about ME/CFS being a psychogenic illness, but is it safe just on those grounds to discount the idea that multiple chemical sensitivity may involve psychological factors?

I really don't know much about MCS, and have not experienced it myself; however, in the MCS review paper referred to in the above article, they say this:

One of these studies used a forced-choice method of provocation and demonstrated that 20% of chemically sensitive participants showed positive responses whether provoked with active or sham substances.

The findings demonstrate that chemical provocation studies that actively mask stimuli show that persons with MCS are unable to differentiate between active and control conditions, symptomatically or otherwise.

And in a similar review on MCS, they say:

In those studies in which blinding was adequate, people reporting MCS were not better able to discern active compared with sham exposures over chance. In some of the studies reviewed, people reporting MCS showed severe responses to sham provocations when they believed these to be active chemicals; in the case of one study, responses were so severe that the trial had to be stopped.

The fact that sham exposures caused severe physical responses on the face of it seems like evidence for psychological factors playing a role in MCS.



Though the James Madison University Environmental Sensitivities Research Team seem to take a dim view of the idea that MCS could have a psychological etiology. They say this:

Psychologically Based Theories

There are researchers and writers who believe that MCS is a psychological illness, although they are in the minority and seem to lack a sophisticated understanding of what people with MCS experience. I have included these theories not because I believe they should be taken seriously, but because familiarity with them reduces the likelihood that they can be used against you effectively (forewarned is forearmed). (See chapter nine for a critique of these theories.)

That webpage at James Madison University lists various different physical theories of MCS, including:

• Limbic Kindling
• Martin Pall's Nitric Oxid Cascade
• Enzymatic Damage/Depletion
• Immunological Insults
• Airway Inflammation
• Candidiasis
• Lyme Disease
• Carbon Monoxide Poisoning
• Additional Brain Changes

I'd like to get the views of someone who knows a lot about MCS research.

He said many patients can get anaphylaxis from a smell alone and must wear a breather mask. He assured me it was very real and for some can be life or death.

But isn't mast cell activation syndrome (MCAS) different to multiple chemical sensitivity (MCS), even though there is a similarity of symptoms?

 

[Thinktank]

My girlfriend suffers from MCS since she got lupus, and it's worse when the disease is in a flare, so there's a causual link. Psychological huh? What's next, lupus being imaginary too? What an idiot.

 

[A.B.]

Assessing via self report will always show that expectations and beliefs influence results. Doesn't mean it's not real. Means Wessely is incompetent.

 

[Gingergrrl]

Phsychological huh? What's next, lupus being imaginary too?

I agree with you @Thinktank and have no interest or desire to argue or debate this issue w/anyone. I did not have MCAS (or any food or chemical reactions) prior to age 44 when my illness became severe after several years of significant mold exposure. These reactions are now as close to remission as possible b/c of IVIG.

But tonight I went to a b-day dinner at a restaurant for my bro-in-law. Was not under any stress, and had no reactions to the food, but there was a very strong chemical/cleaning fluid smell in restaurant and it gave me a headache and I felt very uncomfortable (but nothing to the level of a histamine surge or needing to take medication). My entire family could smell it but to them it was like a 3/10 level smell vs. to me it was like an 8/10 (but they do not have MCAS or allergic reactions so this made sense to me).

There was nothing psychological about the situation and if this would have happened pre-IVIG, I would have had to leave the restaurant immediately and take emergency allergy meds to prevent full-blown reaction.

 

[Valentijn]

... the smell goes through the nose into the limbic system in brain and lodges there and continues to increase vs. dissipate like for a normal person.

Yes, Mr Wessely & Co do seem to have trouble understanding basic physiology.

Simon Wessely may have got it wrong about ME/CFS being a psychogenic illness, but is it safe just on those grounds to discount the idea that multiple chemical sensitivity may involve psychological factors?

Probably not. Simon Wessely cannot be trusted to evaluate the quality of a trial, nor to honestly report the results. Hence he's pretty much the last person who should be doing any sort of review.

 

[Countrygirl]

I was bewildered by the development of what I later discovered was MCS. My first experience of it seemed totally bizarre to me and I had no idea what was causing me to be ill until some weeks later. I had severe ME when I ordered a desk. The desk was delivered, gleaming with varnish, hot off the press, newly manufactured. As it was carried into the house I went to admire it and ...collapsed. For three weeks I couldn't get out of bed I felt so horrible. All the while I could smell the varnish of my gleaming desk but made no connection. Then I noticed as the smell lessened, I started to improve. Slowly I began to suspect that I was being made ill..........by a piece of furniture.......a thought which seemed totally crazy to me.

Next experience was an encounter with a new duvet set. It was put on my bed and didn't it smell!, I assume of formaldehyde. I again,unexpectedly,, had a severe reaction. This time I realised that my bedding was making me ill. Some years later that duvet is still wrapped in plastic, hidden away, still smelling of chemicals.

Then I was taken into a large show tent and within three seconds was on the floor. I was taken outside and quickly recovered. This time I decided to investigate. I learnt that before the show tent was opened that morning the ground inside had been sprayed with a pesticide, but there was no smell.

I have twice been taken into hospital and collapsed. I had to be taken out quickly by a friend and recovered. On both occasions I discovered that both had just newly decorated, so I now have no doubt that the paint fumes (which I didn’t detect) were responsible.

I have had many, many experiences of this now, especially in material, carpet and home-decorating shops.

I completely disagree with Wessley. MCS is very real and one reacts without being able to detect an odor.

 

[Hip]

Hence he's pretty much the last person who should be doing any sort of review.

Well is there anyone here that might be competent enough to perform a review?

This is the paper that found 20% of MCS patients showed positive responses whether provoked with active or sham substances. The full version can be found on Sci-Hub.



Also of interest: the review says:

Three studies used olfactory masking agents to conceal stimuli, and none of these found associations between provocations and response.

Olfactory masking is where you add a second odor to mask the odor/chemical you are testing, so that the person being tested cannot recognize the odor/chemical.

So for some reason, olfactory masking seems to obliterate the chemical sensitivity.

 

[Gingergrrl]

VOC's and mold (and things too numerous to list) can provoke a reaction in sufferers in the absence of any smell. I am not really sure what is considered an "active substance" vs. a "sham substance"? If you are allergic, you are allergic!

By mid-2015, I was allergic and having stage two anaphylaxis to all food but water. No smell was required. There was a point that someone cooking onions was unbearable to me and smells (whether food, cleaning supplies, paint, perfume, BBQ smoke, etc) would remain in my brain for up to 24 hours after no one else could smell them any more. Now I can eat onions with no reaction.

I asked my MCAS doctor about this and he explained that it was a real medical phenomenon and the smell gets lodged into your brain vs. dissipating like it does for a normal person. Now post-IVIG, I can sit with and tolerate the smells, even while eating, and have no reaction beyond feeling uncomfortable. The chemical smell from the restaurant tonight dissipated as soon as I went outside. But two years ago, I would have still smelled it 24 hours later.

My MCAS doctor is one of the top ten specialists world-wide. I think he knows more than Simon Wesseley on this topic.

 

[Sea]

When Simon Wessely can conclude and publish that the Camelford aluminium poisoning event which killed 7 and seriously affected tens of thousands of people and animals was a result of mass hysteria and anxiety, I have no regard for anything he believes.

 

[hixxy]

Also of interest: the review says:
Olfactory masking is where you add a second odor to mask the odor/chemical you are testing, so that the person being tested cannot recognize the odor/chemical.

So for some reason, olfactory masking seems to obliterate the chemical sensitivity.

The masking agents for 2 of the studies are vanilla and peppermint, cinnamon, aniseed. The last 3 alone are loaded with salicylates but salicylates aside all mint is a common trigger for people with MCS. Vanilla certainly can be a trigger but less common. I wonder how pure the vanilla was because most vanilla also contains alcohol which most certainly is a trigger for most people with MCS. I bet these researchers are considering MCS to be multiple synthetic chemical sensitivities and think that anything non-synthetic should be okay as a mask, but that is certainly not the case. These chosen masking agents are a big fail, especially the latter 3.

I have no idea what the masking agent is in the third study as it only says FM.

 

[Gingergrrl]

Although I personally do okay with the smell of vanilla, peppermint and coffee, I do not do well with cinnamon but each individual is unique in what they react to.

And for me, even if I smell coffee grounds or peppermint, it does not mask the original smell. If I am reacting to paint, smoke, perfume, etc, the underlying smell is still there for me and I will still react to it, even if the coffee grounds or peppermint masks it for a few seconds.

When I was really bad in 2015, the original smell could literally stay in my brain for 24 hours after no one else smelled it and my MCAS doctor confirmed this is a real phenomenon. I could not stay in a room w/paint smell and VOC's for more than a few minutes. We tried everything humanly possible to mask the smell but it was futile.

 

[hixxy]

@Gingergrrl That's because you're probably not sensitive to salicylates. People with MCS don't necessarily react to all synthetic chemicals either. Cinnamon can also directly activate TRPA1 because it contains cinnamaldehyde.

 

[Valentijn]

Well is there anyone here that might be competent enough to perform a review?

I honestly don't know, and don't care enough to look into it. But based on his track record, Wessely is pretty much always wrong, which makes me distrust the other reviews as well. He's literally a discredit to his field.

 

[Gingergrrl]

@Gingergrrl That's because you're probably not sensitive to salicylates.

That makes sense b/c I use peppermint toothpaste (dye free) but I could never use a cinnamon toothpaste.

 

[SilverbladeTE]

The problem with Simon is, for flimflam man, he loves the attention too much....

but he HAS gotten too much attention, because he likes it, and all those accolades....

Give a scumbag enough rope, and he'll hang himself and that's exactly what he's done