Skip to content

The denouement

After all the disastrous press related to the Dutch Health Council I really needed to set the record straight and do some explaining. Here’s my response to the opinion piece ME is not ‘purely physical’ by Knoop et al, (our Dutch PACE-trial friends) in response to the Dutch health council in the NRC.


My story.

After my training as a professional ballet dancer at the Royal Conservatory in The Hague, I danced with various international ballet companies. With regards to my last employment I had been living and working in Switzerland. Unfortunately, after a viral infection in 2007, I was forced to end my career.

The days after I got ill I attempted to follow a classical ballet class. However, I had only gotten to the second exercise in the classical training, the plié, when the lactic acid in my muscles got so bad that I felt like I had just danced an entire ballet. I got lightheaded and felt like I had the flu. That feeling lasted about 3 to 4 days in which I felt significantly worse. Suddenly, overnight.

Following the advice of an internal medicine specialist at the hospital I tried cognitive behavioral therapy (CBT) and graded exercise therapy (GET). This resulted in me being much more ill for months, and never again regaining the level of function I had before those treatments. This happened because I was asked to exceed my physical boundaries, despite my body indicating that this was a bad idea. Completely counter-intuitive for a dancer as, obviously, we are used to listening to what our bodies tell us.

Once back in the Netherlands, I was diagnosed with ME at a specialized center in Amsterdam. They performed a number of (exertion) tests and the symptom of getting more ill after exercise was then given the name Post Exertional Malaise (PEM).



In the article by Knoop et al., a description of the disease ME is given. There is talk of fatigue, pain and concentration problems. However, this description lacks a very important symptom, which is Post-Exertional Malaise. This is not mentioned at all. They create an image of this disease as being mainly about chronic fatigue. This notion is a central theme in the studies by professor Knoop and professor Bleijenberg. Often criteria are used where chronic fatigue is the primary focus, and where PEM is only optional (variation on the FUKUDA criteria) or worse: completely absent (variation on the OXFORD criteria).

Studies based on chronic fatigue and not on the core symptom PEM does indeed say little about patients with ME.

The Institute of Medicine (the American Health Council), wrote a report on ME in 2015, which the Dutch Health Council used as basis for its advice. The conclusion of this leading institute was that ME is a chronic, disabling, multisystemic physical disease and not a figment of the imagination or a consequence of psychological suffering. Another interesting development was that they tried to change its name to Systemic Exertion Intolerance Disease. This name did not make it in the end but it emphasizes the symptom Post-Exertional Malaise. They call this symptom “the hallmark” or the core symptom of this disease. So not the fatigue like Knoop et al. have tried to claim.

In America it is now well understood that behavioral intervention studies based on chronic fatigue and not on the core symptom PEM does indeed say little about patients with ME. These are fatigued patients, but this is not the same disease. The prestigious National Institutes of Health (NIH) has now distanced itself from studies using the Oxford criteria. Another large medical institute, the Centers for Disease Control and Prevention (CDC), has now removed the recommendations for CBT and GET from its website. They have added the recommendations of the IOM report on their website and also emphasize the main symptom Post-Exertional Malaise. The IOM, NIH and CDC all state that there is no curative treatment for the disease ME. The Dutch behavioral intervention studies by Knoop et al. are basically no longer accepted by these institutes because they are not based on PEM but thus based on fatigue.

The biggest criticism by professor Knoop about the Dutch Health Council was that he felt he needed to compromise with the patients or patient representatives in the council. That the scientific substantiation of the actual advice from the Dutch Health Council suffered from this. However the IOM report 2015 does not mention CBT and GET at all. All these other institutes are moving away from these treatments as there is no real proof that they actually work or if they are in fact about ME patients. The patient representatives have been safeguarding these facts so that they would be incorporated into the advice. In the end, as there were quite a few CBT proponents, the Dutch Health Council advice is much more lenient towards CBT/GET than what the IOM, CDC, NIH and the AHRQ are. That’s a real bummer for us patients but I’m not really sure if professor Knoop can complain. If we really would’ve followed where science is heading CBT and GET would be out, much like it is happening in US. So his criticism is in my opinion completely unfounded.


Body and mind.

The article claims that patients have problems with CBT because it would suggest that behavioral factors play a role and that behavioral change could reduce the symptoms. That ME would be labeled as a ‘psychological’ condition. Apart from the fact that there is no evidence for the notion that this could actually be a mental illness and that professor Knoop himself already refers to this disease as a somatic illness, the document also refers to diabetes or rheumatism. For these diseases, CBT could also have a beneficial effect because the body and mind are one. There is, however, a very significant difference.

The CBT model for ME suggests that after an initial infection you have physically started doing less. The disease is maintained by false illness beliefs. In other words, you are no longer ill and patients can recover or heal if they can overcome their fear of activities. That any Post-Exertional Malaise symptoms are just normal reactions of the body because you’re deconditioned, not a sign that you’re making things worse. However, this model is based on an ‘as of yet’ unproven hypothesis.

Professor Knoop states in a study from 2008 that recovery is possible even if the physical activity level of patients remained low. So if I interpret this correctly, someone with flu and fever is lying in bed, and when the false illness beliefs have been altered, has someone been healed despite being ill in bed? Peculiar. Although in such studies, like those of Knoop et al., which are unblinded and based purely on subjective measurements, anything seems possible. An important point is that the objective measurements unfortunately do not show any significant improvements.

So this is where the problem lies. CBT is used in various diseases, but when applied to diabetes or rheumatism, CBT does not claim to be a cure. We are talking about a supportive form of CBT, but in the version recommended for ME you are dealing with a “corrective” form which is supposedly “curative”. That is something entirely different. In addition, CBT is not the only treatment offered in these type of diseases. Imagine that. By reducing the disease ME to just fatigue, they project the image of having a cure for the disease itself. That is not the case. Extreme exhaustion is only one of the symptoms as with many diseases. It is not a disease in itself.

CBT is used in various diseases, but when applied to diabetes or rheumatism, CBT does not claim to be a cure.

Due to these claims of being curative, ME patients often get into huge problems with government agencies since these sufferers seemingly do not want to get better. If they refuse to cooperate because they get sicker from building up their activity levels or have ever had bad experiences with this type of treatment, this is interpreted as not wanting to work on their recovery or in other words ‘a cure’ and their social service benefits could consequently be denied. Ouch.

No one will dispute that the body and mind are one. Most certainly not me as a dancer. Us dancers continually work with the interaction between body and mind. I do believe however, from my own experience as a dancer and as an ME patient, that while important, we should not exaggerate the power of the body and mind connection. That is what has happened with this disease and historically with other diseases.


The denouement of the wrong story.

From the start of my being ill, the worsening that came after (minor) exertions was the most disabling symptom. The rest of the laundry list of symptoms are also very burdensome, but if you exceed your physical limit, these symptoms will quadruple. Because of my background, I am naturally used to physically exerting myself. Getting ill after exercise with ME is clearly something entirely different. In my opinion something goes horribly wrong with the immune system and the energy metabolism after exercise. This is an atypical reaction of what you would normally expect after exerting physical effort. Bizarre that this is a concept which is so difficult to understand.

It may well be that these scientists could potentially do a good job for people who are only chronically overtired. With the criteria they’ve been using until now, that’s what they are actually studying, but that is not equal to ME (with PEM). I think it is certainly difficult for them. A paradigm shift is happening with respect to this disease. This shift clearly goes against the CBT model of which these scientists have been convinced of throughout their careers. People worldwide are now doubting their life’s work. Imagine that happening to you…

If you read studies on tuberculosis (TB) you’ll find that scientists wrote that people did not recover due to their personality. It was considered a disease of both the personality/mindset and the lungs, until Streptomycin was discovered. Multiple sclerosis (MS) was regarded as hysteria until the CAT scan demonstrated something else was going on. For these diseases, no one in their right minds would nowadays claim that you could be cured by CBT.

In 2016, several studies were published with new techniques that found disturbances in energy metabolism (metabolites) in ME patients, as compared to the healthy control group. Now in 2018, the findings from one of these studies have already been validated in a follow-up study (not yet published). This is, of course, all preliminary but still a good start.

Could it be that in ME, like MS or TB, the psychological factors play a much less prominent and mostly secondary role, unlike in the studies by Knoop et al. might suggest? So that for the disease ME, there is a predominantly physical substrate? That’s definitely what the emerging picture seems to looks like. To my knowledge, patients have no problems whatsoever with the notion that psychological factors can at times be at play in a severely disabling disease such as ME. This is also seen in other diseases, but solving those factors won’t cure those either.


Sickness doesn’t scare me, death doesn’t scare me. What scares me is that you can disappear because someone is telling the wrong story about you.

– Jennifer Brea, Unrest 2017.


The insights surrounding this disease are starting to change. With the new Dutch Health Council report, the Netherlands is partially joining the world’s leading institutes. The beliefs surrounding the treatments of CBT and GET for ME has greatly diminished. More and more clear physical objective abnormalities are found that can not be attributed to psychological or perpetuating behavioral factors. We are getting closer to a solution for this disease. The findings in the biomedical field are increasingly in line with patients’ experience with this disease. Will this hopefully lead to better care and maybe even new medication? Despite all these positive developments, Knoop et al. are apparently extremely dissatisfied. My sincere question to these scientists: Why the enormous resistance? We are clearly on the right track. Why does care that is better suited to patients really need to be such a huge problem?

Translation: Marloes. Editor: Russel Mohan.

Anil van der Zee

Former professional ballet dancer, teacher, aspiring choreographer & photographer.
Currently life on hold; Myalgic Encephalomyelitis.
Blogging out of necessity.

Follow ME:

Follow Anil van der Zee on