Perception versus practice: the reality of functional neurological disorder FND diagnosis at a large neurological centre, 2026, Nicholas et al.

[SNT Gatchaman]

Perception versus practice: the reality of functional neurological disorder FND diagnosis at a large neurological centre

Spoiler: Authors

Edward Nicholas; James Varley; Richard Nicholas

Functional neurological disorder (FND) encompasses a wide range of neurological symptoms without identified structural pathology.1 Defined by positive clinical signs, FND is supported by a growing literature and inclusion in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition.2 Accounting for 5%–15% of new neurology consultations, FND has an incidence of around 12 per 100 000 per year.3

We conducted a cross-sectional observational study to assess diagnostic rates and clinical perceptions at Imperial College Healthcare NHS Trust, which lacks a dedicated FND service. The International Classification of Diseases, Tenth Revision F44 codes were reviewed for inpatient, outpatient and emergency department attendances between 1 January 2018 and 30 June 2024. Multiple sclerosis (MS) served as a positive control due to its well-established coding and high prevalence. Coding accuracy was verified against a manual review of 9698 clinical records. An anonymised survey of 20 neurologists and registrars explored perceptions, confidence and training.

Nineteen inpatients, 29 outpatients (0.0135%) and 199 emergency department attendances (0.0145%) with FND were identified, compared with 3717 MS cases. Of the 19 inpatient cases, only five were diagnosed by neurologists. Manual review revealed an FND diagnosis rate around 20 times higher (0.40%), most cases labelled ‘functional’ rather than formally coded. In the survey, there was no agreed definition across respondents; the most common being ‘neurological disorder without structural abnormality’. One respondent questioned, “Is it right to label every unexplained symptom as FND?” Seventy-nine per cent acknowledged overlap between FND and organic …

Web | DOI | PDF | Journal of Neurology, Neurosurgery & Psychiatry | Paywall

 

[SNT Gatchaman]

We conducted a cross-sectional observational study to assess diagnostic rates and clinical perceptions at Imperial College Healthcare NHS Trust, which lacks a dedicated FND service.

Nineteen inpatients, 29 outpatients (0.0135%) and 199 emergency department attendances (0.0145%) with FND were identified, compared with 3717 MS cases. Of the 19 inpatient cases, only five were diagnosed by neurologists. Manual review revealed an FND diagnosis rate around 20 times higher (0.40%), most cases labelled ‘functional’ rather than formally coded.

there was no agreed definition across respondents; the most common being ‘neurological disorder without structural abnormality’. One respondent questioned, “Is it right to label every unexplained symptom as FND?”

One reflected on this conceptual tension, saying “I don’t [diagnose FND]—as it isn’t in my area of expertise, it is usually undisclosed PTSD”.

Confidence in diagnoses varied: 57.9% reported moderate confidence, with some expressing little (15.8%) to none (10.5%).

Most (89.4%) believed FND is stigmatised among clinicians and patients, with one remarking “some neurologist colleagues do not consider FND a real diagnosis… way of ‘dismissing the patient’”.

 

[SNT Gatchaman]

F44 codes captured a diagnosis rate of 0.02%, while manual review identified a rate around 20 times higher (0.40%), with most cases documented informally. By contrast, MS cases were reliably captured, reflecting disparity in how established conditions are coded.

Clinicians offered varied definitions of FND, from structured responses invoking a positive diagnostic model and Hoover’s sign, to ‘software-hardware’ comparisons and Zen parables. A recurring theme was uncertainty; several admitted difficulty defining FND, one questioning if it was possible given the evolving science.

Although most clinicians acknowledged that functional and structural conditions can coexist, this did not translate to diagnostic confidence. […] “There seems to be a want (both for patients and neurologists) to find organic causes where one certainly doesn’t exist”.

Stigma was widely reported through dismissive attitudes among colleagues, with FND often avoided, downplayed or trivialised. One noted how the term ‘functional’ is used in humour, while others suggested stigma is more common among professionals than patients.

One stressed the need to understand “why many patients have strong denial”, with the need to address stigma, on both sides of the consultation.

A majority of respondents reported receiving limited to no formal education, and many had low confidence. One clinician admitted plainly, “I’m usually wrong”, while a self-described ‘experienced and shrewd’ neurologist recounted how a misdiagnosis delayed identification of POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, monoclonal plasma cell disorder and skin changes), leaving them “somewhat nervous of diagnosing FND now”.

One noted, “The main problem is the lack of access to help for patients… few neurologists specialise in this common problem”. Another added, “explaining the diagnosis is made more difficult given poor resources for treatment”.

 

[Sean]

“There seems to be a want (both for patients and neurologists) to find organic causes where one certainly doesn’t exist”.​

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“The main problem is the lack of access to help for patients… few neurologists specialise in this common problem”. Another added, “explaining the diagnosis is made more difficult given poor resources for treatment”.​

What do they expect when all they are doing is invoking a non-diagnosis that has only non-treatments, and typically resort to framing the inevitable failure of the whole shit show as due to patient resistance and denial.