Functional Neurological Disorders - discussion thread

where did he make this point?

 

Can you explain why stress plays a larger role in FND?

And why is there emphasis on stress when it is recognized that FND can appear without any particular stress?

I agree. It's better to have a "working title" than nothing. But it does not seem to be a term that is neutral in terms of etiology, it just seems like a new label for the old idea of conversion disorder. Recently I came across a paper where the authors appeared to considered it equivalent to conversion disorder, which is not a working title but a diagnoses attached to a causal explanation.

I am skeptical about claims that they know how to treat FND because from what I've seen they have no adequately controlled clinical trials. Therefore any positive results that they or the patients think are occurring thanks to the treatment may be an illusion created by poor methods.

If you do science with poor methods, it is very easy to create the appearance of having a plausible model supported by research, and a treatment that works. This is what happened in ME/CFS and I fear this is exactly what is occurring with FND too.

 

I'll dig up the studies on the Limbic System/stress tomorrow.
As an addendum, I would like to see more FND research focused on neuro-imaging: trials that test patients before the start of their treatments and afterwards and see what (if any) changes on F-MRI etc

 

I think part of the problem is you putting that framing in your own words. eg If you'd found someone saying "I insist that no physiological dysfunctions could account for these patients' symptoms" then criticising that would be one thing, but my sense is that this is not what a lot of those working on FND would say.

I think FND is really difficult to write about concisely because i) it's complicated, uncertain and touches on areas where old and inaccurate assumptions can be embedded within our language and ii) there seem to have been deliberate attempts to use language in a manipulative way to 'help' patients by managing their beliefs without their fully informed consent (some patients seem unconcerned by this - we all have different preferences and desires... some are just better than others). And other reasons too.

I think that the only way to avoid those issues and produce short blogs on FND would be to avoid any introduction or summary and just present a very dry analysis of specific claims. I could be completely wrong though, and I don't know what the best way to handle all these things is either!

 

Or FND is hard to write about because it's an incorrect explanation.

It is equivalent to conversion disorder, which comes from Freud who used what today would be considered "recovered memory therapy" to unmask the emotional trauma he believed was causing unexplained illness. Recovered memory therapy is now considered a method to implant false memories in patients. Freud also told stories about successfully treating patients with his methods but these were later exposed as fabrications.

It never worked and it never made sense. But medicine has fallen so hard for this scam that it's still trying to apply these ideas and prove they are right. When it didn't work for all the diseases they claimed it would work for in the 1950s they moved on to other diseases. I think what happens when people are very invested in an idea and try to finally prove it is true, they will end lowering their standards of evidence and scientific methodology as much as is necessary to obtain the desired results.

 

I wasn't starting from the assumption that FND is a sensible category or useful label - I don't know. Some people argue that FND is a label detached from any particular understanding of the cause of symptoms, and others argue that providing an explanation of symptoms to patients is an important part of treatment for FND symptoms... some people argue both, perhaps viewing the FND term as one detached from the assumptions underpinning a label like 'conversion disorder' while also believing that such progress in researching FND has been made over the last few years that an explanation of symptoms can now be confidently provided. My impression is that there's an important element of manipulation in both areas and that the claims being made are somewhat dependent on the audience.

The history and culture surrounding the diagnosis is still really worrying, and I think that needs to be properly addressed rather than just brushed under the carpet. I also think that part of informed consent for patients in this area should involve informing them of these problems before having them decide how they want to proceed.

Just writing quick forum posts on FND is a reminder of how difficult it is to not be misleading - I'm sure I'll have done a poor job in important ways!

 

There is no alternative diagnosis that better fits. But the problem with the FND term is that it carries a connotation of psychogenic causation even though the cause of these symptoms is unknown. 'Functional' in neurology and psychiatry is used to imply you have a psychiatric problem (despite equivocation and muddying of the waters by the likes of Stone), not 'functional' in the standard sense of referring to physiology as opposed to anatomy. I'm arguing that the name is bad and stigmatising, not that FND is just a misdiagnosis. (It also frustrates me when some doctors pretend that ME/CFS does not exist and is all a misdiagnosis.)

 

I also wanted to say that even if I doubt that the theory underlying FND is correct, I can accept that the existence of the FND paradigm may be doing more good than harm.

I think it's important that people who are ill are recognized to be ill and diagnosed, at the very least because society expects that. A FND diagnosis can lead to patients being given sensible advice and useful support. It also allows them to find other patients which can be beneficial.

 

Wouldn't a clue to how people using the term FND think about what FND means be in the treatment they believe will be useful in improving function?

 

The term the American Psychiatric Association (APA) chose for use in DSM-5 is "Conversion Disorder (Functional Neurological Symptom Disorder)" and the disorder category was moved under the Somatic Symptom and Related Disorders category block:

Somatic Symptom and Related Disorders

Somatic Symptom Disorder
Illness Anxiety Disorder
Conversion Disorder (Functional Neurological Symptom Disorder)
Psychological Factors Affecting Other Medical Conditions
Factitious Disorder
Other Specified Somatic Symptom and Related Disorder
Unspecified Somatic Symptom and Related Disorder


For ICD-11, the proposed term went through a number of iterations, for example, the proposed term listed in the ICD-11 Beta draft, as it stood in October 2017, had been "Dissociative disorder of movement, sensation, or cognition".

But the disorder parent block term that was settled on for the release in 2019 is "Dissociative neurological symptom disorder", as Sly Saint has noted.

The WHO wished to avoid the term "functional" since it is ambiguous and is used within WHO literature, in ICD-10 and in WHO guidelines in a number of different ways. For ICD-11, the WHO also wished to retain the "Dissociative" element within any proposed name.

The terms:

Functional neurological disorders [Ed: a term already being used in clinical settings]
Functional neurological symptom disorder [Ed: the DSM-5 term]
Conversion disorder [Ed: the prefix to the DSM-5 term]​

are listed in ICD-11 under Synonyms under Dissociative neurological symptom disorder.

Factitious disorders (6D50-6D5Z) are specified Exclusions.


Jon Stone, and Raad Shakir (who chaired the ICD-11 Neurology Topic Advisory Group), lobbied the WHO for several years for inclusion of ICD-11's equivalent disorders to the ICD-10 legacy F44 to F44.9 Dissociative disorders category block under both the Mental, behavioural and neurodevelopmental disorders chapter and the Diseases of the nervous system chapter.

See their 2014 position paper:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4277679/

Functional disorders in the Neurology section of ICD-11
A landmark opportunity
Jon Stone, FRCP, Mark Hallett, MD, [...], and Raad Shakir, FRCP


At one point, the ICD-11 Beta draft had the equivalent to the ICD-10 legacy F44 to F44.9 category block primary parented under the Neurology chapter and secondary parented under the Mental, behavioural and neurodevelopmental disorders chapter.

The lead managing editor for the Mental and behavioural disorders chapter and the ICD Revision Steering Group rejected this proposed structure and the disorder categories that now sit under the Dissociative neurological symptom disorder parent block were dragged back under the mental disorders 6B60 Dissociative disorders parent block:

https://icd.who.int/dev11/f/en#/http://id.who.int/icd/entity/1069443471


Dissociative neurological symptom disorder is, however, secondary parented under the Disorders of the nervous system chapter in the Foundation Linearization - but not in the Mortality and Morbidity Statistics Linearization (implemented in May 2018), as a concession to the recommendations of Stone and Shakir.

(Though Dr Geoffrey Reed, lead managing editor for the Mental and behavioural disorders chapter, had originally argued that this disorder block should be retained in its legacy chapter without secondary parenting under the Diseases of the nervous system chapter.)

Note re ICD-11 and multiple parenting: it is incorrect to refer to "dual coding" in the context of ICD-11. If more than one parent location has been assigned to a category, there is a designated primary parent and a designated secondary parent; it is the primary parent (aka the "linearization parent") location that determines the code for that category.

So Dissociative neurological symptom disorder and its 15 or so child categories are assigned Chapter 6xxx.x codes - not Chapter 8xxx.x codes and in the case of Dissociative neurological symptom disorder, when the category is clicked on in the Diseases of the nervous system chapter, it jump links to its primary location under Dissociative disorders.



[My highlighting]

ICD-11

06 Mental, behavioural and neurodevelopmental disorders

(...)

Dissociative disorders [Ed: Category block]

6B60 Dissociative neurological symptom disorder

Description
Dissociative neurological symptom disorder is characterized by the presentation of motor, sensory, or cognitive symptoms that imply an involuntary discontinuity in the normal integration of motor, sensory, or cognitive functions and are not consistent with a recognized disease of the nervous system, other mental or behavioural disorder, or other health condition. The symptoms do not occur exclusively during another dissociative disorder and are not due to the effects of a substance or medication on the central nervous system, including withdrawal effects, or a Sleep-Wake disorder.


[Under the ICD-11 6B60 Dissociative neurological symptom disorder parent block sit the following child categories which are assigned discrete codes and description texts:]

6B60.0 Dissociative neurological symptom disorder, with visual disturbance
6B60.1 Dissociative neurological symptom disorder, with auditory disturbance
6B60.2 Dissociative neurological symptom disorder, with vertigo or dizziness
6B60.3 Dissociative neurological symptom disorder, with other sensory disturbance
6B60.4 Dissociative neurological symptom disorder, with non-epileptic seizures
6B60.5 Dissociative neurological symptom disorder, with speech disturbance
6B60.6 Dissociative neurological symptom disorder, with paresis or weakness
6B60.7 Dissociative neurological symptom disorder, with gait disturbance
6B60.8 Dissociative neurological symptom disorder, with movement disturbance

>6B60.80 Dissociative neurological symptom disorder, with chorea
>6B60.81 Dissociative neurological symptom disorder, with myoclonus
>6B60.82 Dissociative neurological symptom disorder, with tremor
>6B60.83 Dissociative neurological symptom disorder, with dystonia
>6B60.84 Dissociative neurological symptom disorder, with facial spasm
>6B60.85 Dissociative neurological symptom disorder, with Parkinsonism
>6B60.8Y Dissociative neurological symptom disorder, with other specified movement disturbance
>6B60.8Z Dissociative neurological symptom disorder, with unspecified movement disturbance ​

6B60.9 Dissociative neurological symptom disorder, with cognitive symptoms
6B60.Y Dissociative neurological symptom disorder, with other specified symptoms
6B60.Z Dissociative neurological symptom disorder, with unspecified symptoms


[Edited for clarity and to insert additional coded categories]

 

On June 14, 2018, a proposal and brief rationale was submitted to ICD-11 by an external submitter (Ingo Schäfer, University of Hamburg) for reverting the concept term:

"Dissociative neurological symptom disorder"

back to its October 2017 iteration:

"Dissociative disorders of movement, sensation or cognition".

Proposal: https://icd.who.int/dev11/proposals...lGroupId=9d9fb42d-c4f6-4566-8880-c120ecafb70e


The WHO's Classifications and Statistics Advisory Commitee (CSAC) reviewed this proposal and requested input from the Medical Scientific Advisory Committee (MSAC). In November 2019, the following response was posted by the MSAC Secretariat:

https://icd.who.int/dev11/proposals...lGroupId=9d9fb42d-c4f6-4566-8880-c120ecafb70e

The current terminology for this entity and its children was the result of an agreement between the Mental Health TAG and the Diseases of the Nervous System TAG. Specifically, the agreement was to retain these categories in the mental disorders chapter and to refer t the overarching parent entity as dissociative neurological symptom disorder, with functional neurological disorders included as a synonym. This is similar to the terminology in DSM-5, which refers to these as ‘functional neurological symptom disorders’. The Mental Health TAG preferred to avoid the term ‘functional’ in the entity title as within mental health this term is often seen as dated and sometimes as pejorative. Instead, the term ‘dissociative’ was retained in order to anchor them clearly in the dissociative disorders grouping. There is no rationale or evidence presented in this proposal based on which to override this decision.

MSAC recognizes that the symptoms presented as a part of this disorder are by definition not due to a disease of the nervous system, but they mimic neurological symptoms and patients with these presentations are commonly referred to neurologists for evaluation.

RECOMMENDATION: MSAC recommends that the proposal be rejected.

MSAC Secretariat 2019-Nov-18 - 18:25 UTC​

 

In March 2017, a proposal was submitted to ICD-11 by Bridget Mildon (President, FND Hope, United States of America) to change the concept term to:

Functional neurological disorder.


This proposal was rejected in April 2017, by the Mental Health Topic Advisory Group, with this rejection rationale note:

https://icd.who.int/dev11/proposals...lGroupId=0f8e501b-ce8f-4d42-b54e-e146623d44da

This was discussed at length, and a decision was affirmatively made by the Mental Health TAG not so use this title as the main term. While the term 'functional' is often considered out of date, pejorative, and imprecise in the mental health field, the TAG is aware that the term is used differently in other areas. For this reason, it has been included as a synonym.

--On behalf of Mental Health TAG

Geoffrey Reed 2017-Apr-12 - 02:09 UTC​

 

I didn't notice that until now. But post #7 is the best post!

 

It is difficult to talk about FND because it is a mess. You can't disagree with what they say it is because they can't be pinned down to anything in particular. The lists from Dx Revision Watch are the clearest I have ever seen but that is not how they talk about it in papers or to patients.

So there you have it, by definition there is no disease of the nervous system.

But how on Earth can the know there is no disease of the nervous system? Are the workings of the brain so well understood there is nothing left to learn?

If I can quote from a facebook post by Voices from the Shadows

Yet in neurology anything slightly off the norm is psychogenic.

There is nothing in biology which can account for seizures on the one hand and the pain and inflammation of interstitial cystitis on the other. The only linking factor is that some neurologists have decided that they can both be treated by CBT.

Long lists of symptoms and diseases that can be treated by the proponents single favoured treatment is the hallmark of pseudoscience and nothing in the "research" makes me think otherwise.

 

Note that the ICD-11 MMS, released in 2018 to enable member states to start preparations for implementation, includes only a brief disorder description text for 6B60 Dissociative neurological symptom disorder and a brief disorder description for each of its 6B60.0 to 6B60.9 child categories.

Unlike DSM-5, ICD-11 does not commonly provide rigid criteria sets for the mental disorder chapter categories.

Instead, expanded disorder description texts will be included in the "Clinical Descriptions and Diagnostic Guidelines for ICD‐11 Mental, Behavioural and Neurodevelopmental Disorders (CDDG)" which will be ICD-11's equivalent publication to ICD-10's "Blue Book" [link is for PDF download].


The ICD-11 CDDG will provide expanded clinical descriptions, essential (required) features, boundaries with other disorders and normality, differential diagnoses, additional features, culture-related features and codes for all mental and behavioural disorders commonly encountered in clinical psychiatry and is intended for mental health professionals and for general clinical, educational and service use.

This ICD-11 companion publication is not yet publicly available but is expected to be completed and released this year. The WHO had said, last year, that they planned to release the CDDG "as soon as possible after WHA's adoption of ICD-11". But I am given to understand that the completion of field trial evaluations for some disorder categories was still in progress, late last year, and this may be causing the delay in the finalization of the CDDG texts.

Whilst clinicians have been able to register with the Global Clinical Practice Network to review and provide feedback on the draft CDDG texts, no drafts have been made available at any point in the development process for public stakeholder scrutiny and comment.

I have had sight of the draft text for Dissociative neurological symptom disorder as the texts had stood in 2016/17, when the parent class disorder term was still proposed as "Dissociative disorders of movement, sensation or cognition". These CDDG draft texts (which included the draft text for Bodily distress disorder) were not intended to be publicly released by the WHO but were inadvertently let loose into the public domain and I stumbled upon them; so I won't post them here, and in any case, the texts will likely have been subject to minor revisions between 2017 and 2018.

When the "Clinical Descriptions and Diagnostic Guidelines (CDDG) for ICD‐11 Mental, Behavioural and Neurodevelopmental Disorders" has been finalized and released, I will post a link for the download and a full copy of the expanded disorder description texts for both 6C20 Bodily distress disorder and 6B60 Dissociative neurological symptom disorder in my thread:

Updates on status of ICD-11 and changes to other classification and terminology systems

-----------------------------------

DSM-5:

For completeness, the diagnostic criteria set and symptom specifiers for DSM-5's "Conversion Disorder (Functional Neurological Symptom Disorder)" are set out at the link below. (DSM-5 criteria sets and disorder description texts are copyright, so I cannot reproduce them here without licensing permissions from APA Publishing.)

Scroll down to the heading:

CONVERSION DISORDER (FUNCTIONAL NEUROLOGICAL SYMPTOM DISORDER)

http://www.workingfit.co.uk/medical...s/dsm-5-somatic-symptom-and-related-disorders


Note that the text beginning: "Terminology can get confusing when clinicians are describing Conversion Disorder..." is not taken from the APA's DSM-5 disorder description text.

Within the DSM-5, there are 3.5 pages of disorder description text for Conversion Disorder (Functional Neurological Symptom Disorder) (pp 318-321), which include the criteria set and specifiers; Diagnostic Features; Associated Features Supporting Diagnosis; Prevalence; Development and Course; Risk and Prognostic Factors; Culture-Related Diagnostic Issues; Gender-Related Diagnostic Issues; Functioning Consequences of Conversion Disorder; Differential Diagnosis; Comorbidity.

 

It would also be difficult to talk about how the position of the planets causes disease and misfortune.

One couldn't discuss a mechanism because there is none. All one could do is insist that it's happening somehow, and point to anecdotes and inevitably flawed correlational data, or run some unblinded uncontrolled clinical trials and pretend there's more than a placebo effect.

 

Sorry for the late reply, quite a busy week and a Chrome-sync issue that caused the deletion of all my bookmarks!

Over the last couple of years some hints for mechanisms in FND have been found, but nothing solid yet.
Concerning the causes for FND, there are only correlations. I feel that in Neurology the label psychogenic is the 'God of the Gaps'
Tomorrow I hope to find all my FND bookmarks again, I might have them on my old phone.